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FIELD OF INVENTION [0001] The present invention relates to a communication system, in particular to reporting to a network node. BACKGROUND TO THE INVENTION [0002] A diverse range of communication systems are in use today enabling communication between two or more entities, such as user equipment and/or other nodes associated with the system. Such systems may comprise, for example, communication of voice, data, and multimedia data. [0003] Communication systems proving wireless communication for user terminals or other nodes are known. An example of a wireless system is a public land mobile network (PLMN). A PLMN is typically a cellular network wherein a base transceiver station (BTS) or similar access entity serves user equipment (UE) such as mobile stations (MS) via a wireless interface. The operation of the apparatus required for the communication is usually controlled by one or more control entities, which themselves may be interconnected. One or more gateway nodes provide for connecting the PLMN to other networks. Examples of other such networks are another cellular network, a public switched telephone network (PSTN) and packet switched data networks such as an IP (Internet Protocol) based network. The communication between the user equipment and the other elements of the communication system are based on an appropriate communications protocol, which defines the “rules” under which communication is handled in the system. [0004] In the current third generation (3G) wireless system, there are defined various servers for the handling of different communication services for mobile users. These include servers that provide call state control functions, known as CSCFs. Control functions may also be provided by entities such as a home subscriber server (HSS) and various application servers. The HSS is typically for permanently storing the user's (subscriber's) profile. For example, in the Release 5 architecture for 3G, as specified by the 3 rd Generation Partnership Project (3GPP), these entities can be found located in the IP Multimedia Subsystem (IMS). [0005] The IMS network may sit at the hub of the 3G architecture, supporting an IP based network that handles both traditional voice telephony and multimedia services. The 3GPP has chosen Session Initiation Protocol (SIP) as a core session signalling protocol for 3G networks. SIP has been developed by the Internet Engineering Task Force (IETF). The 3GPP specification 24.229 describing the IMS network basic operation from an SIP perspective can be found at http://www.3gpp.or/ftp/Specs/Latest-drafts/24229-201.zip. It should be noted that SIP is a request/response style protocol, in the sense that for every message sent from a source, there is an associated response from the destination confirming receipt of the sent message. [0006] For example, in a 3G network, when a user first switches on his mobile terminal, he must register his user ID or address with the network before allowing the terminal to fully connect. This is done by sending an SIP ‘REGISTER’ message, which includes details of the users address, from the terminal to the IMS. The IMS processes this information, via the serving call state control function (S-CSCF), storing the relevant registration information at the HSS. This registration information may include the status of the user such as the location, terminal capability and user availability. The registration is acknowledged by the IMS through a suitable response message that is also in accordance with SIP. Subsequent registrations also take place (‘re-REGISTER’) whenever the preceding registration has expired, or when there is a change in the status of the user or another reason to refresh the registration. When a user wishes to set up a session with another user, such as a voice call or sending of a text message, the session negotiation will also be performed under SIP. Typically such a negotiation will use the SIP INVITE message, which is sent from one user to another via the IMS. [0007] Other services, such as instant messaging, local traffic reports, and conferencing facilities, are supplied by application servers (AS) via the IMS. An AS may reside within the IMS network, or outside of it. Typically the AS is external when the service supported is provided by a third party. For example, an AS providing local traffic reports may need the latest information on the status of any users subscribing to that service. As we have noted above, status information can be updated using an SIP re-REGISTER message. The AS server requiring this status information therefore subscribes, using an SIP SUBSCRIBE message, to all the REGISTER messages sent by each and every user subscribing to the instant messaging service offered by the AS. One SUBSCRIBE message is required per subscriber that the AS wishes to receive updates on. The IMS logs these SUBSCRIBE messages, and sends out a NOTIFY message to the AS every time a relevant REGISTER message is received. The AS can then use this information to implement its traffic reporting service. [0008] The reception of a REGISTER message can be classified as an event. Events can be any change of state and associates with an entity, such as a user or another node, in the communication system. Thus an AS can subscribe specifically to REGISTERs, as in the above example, other SIP messages such as INVITEs, or other status changes not specifically associated with an individual SIP message. [0009] Currently, when an external AS or other element subscribes to events in the IMS, it needs to provide the address of a specific IMS element, such as an S-CSCF, that it wishes to send the SUBSCRIBE message to. The internal structure of the IMS is therefore not entirely transparent, and requires the AS to have certain knowledge of where the SUBSCRIBE messages should be addressed. Specifically, the AS requires an exact address for locating the S-CSCF. The IMS operator would normally be reluctant to disclose specific addressing information to the operator of the AS, which would reveal much about the internal configurations of the IMS operator's proprietary system. [0010] An AS may have many users subscribing to the service it provides. In such a situation, the AS would have to send as many SUBSCRIBE messages as it has subscribing users, and also need to know where to send each SUBSCRIBE message as each user may register its status with different elements (S-CSCFs) in the IMS. [0011] It shall be appreciated that although the above discussed problems relate to subscriptions to SIP events in IP based third generation (3G) communication systems, similar disadvantages may associate with other systems as well and thus the description is not limited to these examples. SUMMARY OF THE INVENTION [0012] Embodiments of the present invention aim to overcome one or several of the above problems. [0013] According to one aspect of the present invention, there is provided a communication system comprising a multimedia network comprising an information storage entity for storing user information and call state control function entities; an entity that is external to the multimedia network and arranged to subscribe to the multimedia network for notifications regarding events that associate with at least one other entity of the communication system, the arrangement being such that subscription messages from the external entity are routed to at least one call state control function entity based on information stored in said information storage entity, said at least one call state control function entity is provided with storage means for storing information received in said subscription messages, and said at least one call state control function entity sends a notification in response to an event defined by said information stored at the storage means. [0014] In preferred embodiments of the present invention, the subscription messages are routed to the at least one call state control function entity via the information storage entity. The multimedia network may comprise an IP multimedia subsystem (IMS). [0015] Preferably the information stored at the information storage entity contains information regarding those call state control function entities the external entity can subscribe to. [0016] Preferably, the notification is sent to the external entity, and the external entity may comprise an application server. Specifically, the application server may be presence server. The information storage entity may comprise a home subscriber server. The call state control function entity may comprise a serving call state control function entity. The external entity may comprise a user equipment. [0017] Preferably the at least one other entity comprises a user equipment. [0018] The communication system may operate in accordance with a session initiation protocol (SIP), and the events are events of that protocol. The subscription message may comprise a SIP SUBSCRIBE message, and the notification comprises a SIP NOTIFY message. [0019] According to a second aspect of the present invention, there is provided a method for sending notifications in a communication system comprising a multimedia network, an entity that is external to the multimedia network and at least one other entity, the multimedia network including an information storage entity and call state control function entities, the method comprising: subscribing by the external entity to the multimedia network for notifications regarding events associated with the at least one other entity; routing of subscription messages from the external entity to at least one call state control function entity based on information stored in said information storage entity; storing in storage means associated with said at least one call state control function entity information received in said subscription messages; and sending a notification by the call state control function in response to an event defined by said information stored at the storage means. BRIEF DESCRIPTION OF DRAWINGS [0020] Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which: [0021] FIG. 1 illustrates a communication system wherein the present invention can be applied; [0022] FIG. 2 illustrates one embodiment of the present invention; [0023] FIG. 3 illustrates an example of a multimedia network [0024] FIG. 4 illustrates the message flow from an Application Server to the IMS, and from a User Endpoint and the IMS during subscription of events in an embodiment of the present invention; and [0025] FIG. 5 illustrates the message flow of another embodiment of the present invention. DETAILED DESCRIPTION OF EMBODIMENTS [0026] Reference will now first be made to the FIG. 1 , which illustrates a typical 3 rd Generation (3G) Wireless telecommunications system operating under the Universal Mobile Telecommunications System (UMTS). At the hub of this system is the IP Multimedia Subsystem (IMS) 110 network, which routes calls between two or more users of the network. Examples of users are mobile terminal 100 of the home network, mobile terminal 122 in a visited mobile network 120 , Public Switched Telephone Network (PSTN) telephone 132 , computer terminal 142 , and application server (AS- 1 ) 144 , such as a presence server, and application server (AS- 2 ) 146 . Examples not shown in FIG. 1 may include laptops, personal desktop assistants (PDAs), and other suitably configured devices. The IMS uses an IP based network to handle these calls, which may include both voice calls and multimedia calls. [0027] The IMS network effectively acts as a gateway in a 3G system between a mobile terminal and other networks such as other mobile networks 120 , PSTN systems 130 , and external IP based networks 140 . Signalling between the mobile terminal and other users of the IMS network, and within the IMS network, is done under the Session Initiation Protocol (SIP). [0028] Typical nodes between the mobile terminal 100 and the IMS include a base transceiver station (BTS) 102 , a radio network controller (RNC) 104 , a serving GPRS (General Packet Radio Service) support node (SGSN) 106 , and a gateway GPRS support node (GGSN) 108 . These are typically referred to collectively as the 3G mobile core network 150 . The GGSN acts as the gateway from the mobile core network to the IMS. [0029] The 3G mobile core network 150 , the IMS network 110 , and the IP based network 140 are all considered part of the home network of the mobile terminal 100 . The mobile terminal 122 is shown communicating with a visited mobile network 120 . This network may also operate under a 3G system, in which case it too will have similar elements to those shown in the rest of FIG. 2 , including its own IMS network. The link between the home network and the visited network will be at an interface between the home IMS network and the visited IMS network. [0030] Reference will now be made to FIG. 2 , which shows a detailed schematic of the home IMS network (IMS 1 ) 110 and the visited IMS network (IMS 2 ) 250 in an embodiment of the present invention. IMS 1 includes various elements including several Call State Control Functions (CSCF) 202 , 206 , 208 and 210 , and a Home Subscriber Server (HSS) 204 . A CSCF is equivalent to a SIP server in the IETF architecture. [0031] The Interrogating CSCF (I-CSCF) 202 is the basic IMS node used for terminating calls in the IMS network, functioning at the edge of the network. Here, it is shown communicating with the external nodes of the mobile terminal 100 (indirectly via Proxy-CSCF 210 ), and the application server (AS- 1 ) 144 . It should be appreciated that the connections between the mobile terminal and the application server to the I-CSCF may not be direct, but via a suitable intermediate network such as the mobile core network 150 for the mobile terminal, and the Internet 140 for the application server, as shown in FIG. 1 . [0032] The Proxy CSCF (P-CSCF) 210 is the first point of call in a visited IMS network. Its primary task is to route messages from the visited IMS network to the home IMS network, or more specifically to the I-CSCF before registration has taken place or to the S-CSCF once registration has taken place. It also performs a similar role in the home network for a user such as mobile terminal 100 . [0033] The S-CSCFs, 206 and 208 , are the IMS nodes responsible for invoking services related to IMS users. They also act as the registrars for IMS users, where registrations from users are processed. It is therefore the S-CSCFs that detect the specific events subscribed to any associated user, then sends out an appropriate NOTIFY message. [0034] Normally the REGISTER message from a user is routed from the P-CSCF to the I-CSCF, which in turn routes it to the appropriate S-CSCF. However, during registration the network normally returns the address of the S-CSCF to the P-CSCF. Thus, once registration has taken place, subsequent non-REGISTER messages will be routed directly from P-CSCF to S-CSCF. [0035] It should be appreciated by those skilled in the art the connections between the elements shown in FIG. 2 are not exhaustive, and others may exist depending on the nature of the messages sent. For example, in terminating calls, when calling party's home network (IMS 1 ) connects to called party's home network (IMS 2 ), the connection will normally be made from S-CSCF 206 of calling party towards I-CSCF 254 of called party's IMS network, and not via the P-CSCF. This and other similar connections have not been shown for the sake of simplicity. [0036] A simplified example of the typical message flow for a SUBSCRIBE from User A to REGISTER messages from User B is as follows: 1. S-CSCF in user B's home domain receives a SUBCRIBE to REGISTER events of User B from User A; 2. S-CSCF updates its database with this new event package subscription relating to User A, and acknowledges receipt of the SUBSCRIBE message with a 200 OK message; 3. User B then sends a REGISTER message to S-CSCF; 4. S-CSCF in user B's home domain acknowledges receipt of the REGISTER message with a 200 OK message to User B; and then 5. S-CSCF in user B's home domain sends a NOTIFY message to User A to inform of the REGISTER message it has just received from User B; 6. User A responds with a 200 OK message. [0043] Another example of the message flow for a SUBSCRIBE from an application server AS to REGISTER messages from User B is as follows: 1. S-CSCF in user B's home domain receives a SUBCRIBE to REGISTER events of User B from AS; 2. S-CSCF updates its database with this new event package subscription relating to AS, and acknowledges receipt of the SUBSCRIBE message with a 200 OK message; 3. User B then sends a REGISTER message to S-CSCF; 4. S-CSCF in user B's home domain acknowledges receipt of the REGISTER message with a 200 OK message; and then 5. S-CSCF in user B's home domain sends a NOTIFY message to inform AS of the REGISTER message it has just received from User B; 6. AS responds with a 200 OK message. [0050] What is important in the embodiments of the present invention is that the S-CSCF maintains information on each user's service profile and thus knows which user has services in which AS. The S-CSCF also maintains a record of the ASs and the SIP event packages they have subscribed to. This means that for any AS used by an IMS user registered to a given S-CSCF, there is information on which SIP events each AS has subscribed to. As shown above, this SIP event information is updated whenever the S-CSCF receives a subscription for a SIP event from an AS. In effect, this means that an AS can subscribe to all relevant users in the IMS network with just one SUBSCRIBE message. [0051] Note that the user information and the AS event subscription information is separated in the S-CSCF's database, which means that the general subscriptions to SIP events, relating to any IMS user, are stored only once per AS. [0052] The HSS is a centralised user database that interfaces with both the I-CSCF and the S-CSCF, storing information on all users of the IMS. In one embodiment of the present invention, the HSS maintains a database of all external ASs which are allowed to subscribe to SIP events occurring in the IMS network, thereby performing a filter function on the ASs. The database contains relevant information on which S-CSCFs in the IMS relates to specific SIP event subscriptions for each AS. An example of the database in the HSS is shown in FIG. 3 . [0053] In FIG. 3 , the database for AS- 1 , 302 , is shown to include the following entries: AS- 1 SUBSCRIBE to REGISTER events SUBSCRIBE to INVITE events attached S-CSCFs S-CSCF- 1 [0059] Likewise, the database for AS- 2 , 304 , includes the following entries: AS- 2 SUBSCRIBE to REGISTER events attached S-CSCFs S-CSCF- 1 S-CSCF- 2 [0065] Only 2 entries, 302 and 304 , have been shown in this embodiment, but there may be more entries depending on the number of application servers that are in use. [0066] The arrangement above means that the list of S-CSCFs connected to the AS must be updated whenever the AS is configured to some user's profile i.e. whenever any user signs up for the services of the AS. [0067] However it is important to note that user profile information and the AS information are stored separately in the HSS database. [0068] The visited IMS network 250 shown includes similar elements to the home IMS network. There is P-CSCF 252 , an I-CSCF 254 , a S-CSCF 256 , and a HSS 258 . Also shown is a visiting mobile terminal 122 in communication with the P-CSCF in the visited IMS network. This P-CSCF will forward any messages from the mobile terminal 122 back to its home IMS network via I-CSCF 202 or directly to S-CSCF 206 as appropriate. [0069] FIG. 4 shows the typical message flow when AS- 1 subscribes to the REGISTER event in one embodiment of the present invention, where the I-CSCF sends the SUBSCRIBE message to S-CSCF directly. FIG. 5 shows another embodiment where the HSS is used as a proxy by the I-CSCF for sending the SUBSCRIBE message to the appropriate S-CSCF. [0070] The function of the elements in FIG. 2 , in relation to how subscriptions to SIP events are handled in the home IMS network, will now be described in more detail at first with reference to the message flow diagram FIG. 4 , then FIG. 5 . [0071] FIG. 4 describes the following process: 1. AS- 1 144 sends an SIP ‘SUBSCRIBE to REGISTER events’ message, S 1 , to the IMS, which is handled initially by the I-CSCF 202 . This can be done as the IMS address used to direct the message to the IMS should point towards an I-CSCF node for terminating sessions. 2. The I-CSCF then queries, S 2 , the HSS for a list of S-CSCFs to which the SUBSCRIBE messages from AS- 1 should be sent to. 3. HSS 204 returns a list, S 3 , of all relevant S-CSCFs to I-CSCF. In this case it is S-CSCF- 1 206 . 4. I-CSCF proxies the SUBSCRIBE message to S-CSCF- 1 , S 4 . S-CSCF- 1 receives the SUBSCRIBE and updates this new SIP event package subscription to its database for AS- 1 . Information as to the source of the SUBSCRIBE message, in this case AS- 1 , can be found within the message. 5. S-CSCF- 1 acknowledges, S 5 , the SUBSCRIBE to the I-CSCF with a ‘200 OK’ message. 6. I-CSCF receives the acknowledgement from S-CSCF- 1 and sends a similar acknowledgment, S 6 , to AS- 1 . 7. User Endpoint (UE), which in this example is the mobile terminal 122 , sends a REGISTER message, S 7 , to P-CSCF 252 . 8. P-CSCF routes, S 8 , this message to I-CSCF 202 . 9. I-CSCF queries, S 9 , the HSS for information on which S-CSCF the REGISTER message should be sent to. 10. I-CSCF forwards the REGISTER message, S 10 , to S-CSCF- 1 . 11. S-CSCF- 1 acknowledges the REGISTER with a ‘200 OK’ message, S 11 a, to the I-CSCF which routes it back, S 12 a and S 13 a, to the UE. 12. S-CSCF- 1 checks the service profile of UE to find all ASs associated with it. It then checks what subscriptions each of those ASs have made. 13. In this case, S-CSCF- 1 finds that UE is associated with AS- 1 , and that AS- 1 has subscribed to REGISTER events. It therefore sends a NOTIFY message, S 11 b, to AS- 1 to inform it of this occurrence. 14. AS- 1 acknowledges with a ‘200 OK’ message, S 12 b. This acknowledgment may contain additional information on the success of the subscription. [0086] FIG. 5 describes a similar process to FIG. 4 , but here the I-CSCF uses the HSS to proxy the S-CSCF on its behalf, rather than doing so directly. The process is therefore identical except for steps S 2 to S 5 of FIG. 4 , which are effectively replaced by steps T 2 to T 5 in FIG. 5 . Steps T 2 to T 5 will now be discussed in further detail below: 1. When I-CSCF receives the SUBSCRIBE message, T 1 , from AS- 1 , it proxies the message, T 2 , to the HSS. 2. The HSS looks up in its list which S-CSCFs the SUBSCRIBE message should be sent to, in this case S-CSCF- 1 , and in turn proxies the SUBSCRIBE message, T 3 , to S-CSCF- 1 . 3. S-CSCF- 1 receives the SUBSCRIBE message and updates this new event package to its database for AS- 1 , and sends an acknowledgment, T 4 , to HSS, which proxies it back, T 5 , to the I-CSCF. [0090] The remaining processes from T 6 to T 12 b are the same as the numerical equivalents S 6 to S 12 b. [0091] One advantage of embodiments of the present invention is that any external network node, such as application servers, user equipment, or any other user operating under SIP, may approach the IMS network as if it were a standalone SIP server. As a result, external nodes may use the IMS address of an IMS entity (e.g. IMS user or IMS ‘registrar’) and send any SIP event subscriptions to IMS without needing to know the internal architecture of the IMS network. This is an important advantage as otherwise the AS would have to know precisely which user is served by which S-CSCF before it sending its subscriptions. A further benefit of hiding the internal structure of the IMS is provided for operators who do not want their competitors gaining knowledge of their proprietary architecture. [0092] Another advantage is that with a single SUBSCRIBE message, an AS can subscribe to events associated with a plurality or all the relevant users in the IMS network without requiring one message per user as previously. This may simplify subscription management in the AS significantly. Consequently, as the IMS elements only need to store one subscription per AS and not separate data relating to each and every user to the AS, considerable savings in storage requirements may be gained, in particular at entities such as the HSS and S-CSCF. [0093] The embodiments also provide for greater flexibility in the addressing of the AS, allowing for multiple addresses per AS. This means that a single AS can present itself to the IMS with different addresses, which allows for a variety of event subscription schemes between different IMS users. [0094] It should be appreciated that the IMS network 110 may also comprise further S-CSCFs and Proxy CSCFs (P-CSCF). Likewise, although embodiments of the present invention have been described in the context of 3G using SIP, other suitable systems and interface protocols could be used. [0095] It is also noted herein that while the above describes exemplifying embodiments of the invention, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention as defined in the appended claims.
A communication system comprising a multimedia network and an entity that is external to the multimedia network and arranged to subscribe to the multimedia network for notifications regarding events that associates with at least one other entity of the communication system. The multimedia network comprises an information storage entity for storing user information and call state control function entities. The arrangement being such that subscription messages from the external entity are routed to at least one call state control function entity based on information stored in said information storage entity. The at least one call state control function entity is provided with storage means for storing information received in said subscription messages, and the at least one call state control function entity sends a notification in response to an event defined by said information stored at the storage means.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "FIELD OF INVENTION [0001] The present invention relates to a communication system, in particular to reporting to a network node.", "BACKGROUND TO THE INVENTION [0002] A diverse range of communication systems are in use today enabling communication between two or more entities, such as user equipment and/or other nodes associated with the system.", "Such systems may comprise, for example, communication of voice, data, and multimedia data.", "[0003] Communication systems proving wireless communication for user terminals or other nodes are known.", "An example of a wireless system is a public land mobile network (PLMN).", "A PLMN is typically a cellular network wherein a base transceiver station (BTS) or similar access entity serves user equipment (UE) such as mobile stations (MS) via a wireless interface.", "The operation of the apparatus required for the communication is usually controlled by one or more control entities, which themselves may be interconnected.", "One or more gateway nodes provide for connecting the PLMN to other networks.", "Examples of other such networks are another cellular network, a public switched telephone network (PSTN) and packet switched data networks such as an IP (Internet Protocol) based network.", "The communication between the user equipment and the other elements of the communication system are based on an appropriate communications protocol, which defines the “rules”", "under which communication is handled in the system.", "[0004] In the current third generation (3G) wireless system, there are defined various servers for the handling of different communication services for mobile users.", "These include servers that provide call state control functions, known as CSCFs.", "Control functions may also be provided by entities such as a home subscriber server (HSS) and various application servers.", "The HSS is typically for permanently storing the user's (subscriber's) profile.", "For example, in the Release 5 architecture for 3G, as specified by the 3 rd Generation Partnership Project (3GPP), these entities can be found located in the IP Multimedia Subsystem (IMS).", "[0005] The IMS network may sit at the hub of the 3G architecture, supporting an IP based network that handles both traditional voice telephony and multimedia services.", "The 3GPP has chosen Session Initiation Protocol (SIP) as a core session signalling protocol for 3G networks.", "SIP has been developed by the Internet Engineering Task Force (IETF).", "The 3GPP specification 24.229 describing the IMS network basic operation from an SIP perspective can be found at http://www[.", "].3gpp.", "or/ftp/Specs/Latest-drafts/24229-201.", "zip.", "It should be noted that SIP is a request/response style protocol, in the sense that for every message sent from a source, there is an associated response from the destination confirming receipt of the sent message.", "[0006] For example, in a 3G network, when a user first switches on his mobile terminal, he must register his user ID or address with the network before allowing the terminal to fully connect.", "This is done by sending an SIP ‘REGISTER’ message, which includes details of the users address, from the terminal to the IMS.", "The IMS processes this information, via the serving call state control function (S-CSCF), storing the relevant registration information at the HSS.", "This registration information may include the status of the user such as the location, terminal capability and user availability.", "The registration is acknowledged by the IMS through a suitable response message that is also in accordance with SIP.", "Subsequent registrations also take place (‘re-REGISTER’) whenever the preceding registration has expired, or when there is a change in the status of the user or another reason to refresh the registration.", "When a user wishes to set up a session with another user, such as a voice call or sending of a text message, the session negotiation will also be performed under SIP.", "Typically such a negotiation will use the SIP INVITE message, which is sent from one user to another via the IMS.", "[0007] Other services, such as instant messaging, local traffic reports, and conferencing facilities, are supplied by application servers (AS) via the IMS.", "An AS may reside within the IMS network, or outside of it.", "Typically the AS is external when the service supported is provided by a third party.", "For example, an AS providing local traffic reports may need the latest information on the status of any users subscribing to that service.", "As we have noted above, status information can be updated using an SIP re-REGISTER message.", "The AS server requiring this status information therefore subscribes, using an SIP SUBSCRIBE message, to all the REGISTER messages sent by each and every user subscribing to the instant messaging service offered by the AS.", "One SUBSCRIBE message is required per subscriber that the AS wishes to receive updates on.", "The IMS logs these SUBSCRIBE messages, and sends out a NOTIFY message to the AS every time a relevant REGISTER message is received.", "The AS can then use this information to implement its traffic reporting service.", "[0008] The reception of a REGISTER message can be classified as an event.", "Events can be any change of state and associates with an entity, such as a user or another node, in the communication system.", "Thus an AS can subscribe specifically to REGISTERs, as in the above example, other SIP messages such as INVITEs, or other status changes not specifically associated with an individual SIP message.", "[0009] Currently, when an external AS or other element subscribes to events in the IMS, it needs to provide the address of a specific IMS element, such as an S-CSCF, that it wishes to send the SUBSCRIBE message to.", "The internal structure of the IMS is therefore not entirely transparent, and requires the AS to have certain knowledge of where the SUBSCRIBE messages should be addressed.", "Specifically, the AS requires an exact address for locating the S-CSCF.", "The IMS operator would normally be reluctant to disclose specific addressing information to the operator of the AS, which would reveal much about the internal configurations of the IMS operator's proprietary system.", "[0010] An AS may have many users subscribing to the service it provides.", "In such a situation, the AS would have to send as many SUBSCRIBE messages as it has subscribing users, and also need to know where to send each SUBSCRIBE message as each user may register its status with different elements (S-CSCFs) in the IMS.", "[0011] It shall be appreciated that although the above discussed problems relate to subscriptions to SIP events in IP based third generation (3G) communication systems, similar disadvantages may associate with other systems as well and thus the description is not limited to these examples.", "SUMMARY OF THE INVENTION [0012] Embodiments of the present invention aim to overcome one or several of the above problems.", "[0013] According to one aspect of the present invention, there is provided a communication system comprising a multimedia network comprising an information storage entity for storing user information and call state control function entities;", "an entity that is external to the multimedia network and arranged to subscribe to the multimedia network for notifications regarding events that associate with at least one other entity of the communication system, the arrangement being such that subscription messages from the external entity are routed to at least one call state control function entity based on information stored in said information storage entity, said at least one call state control function entity is provided with storage means for storing information received in said subscription messages, and said at least one call state control function entity sends a notification in response to an event defined by said information stored at the storage means.", "[0014] In preferred embodiments of the present invention, the subscription messages are routed to the at least one call state control function entity via the information storage entity.", "The multimedia network may comprise an IP multimedia subsystem (IMS).", "[0015] Preferably the information stored at the information storage entity contains information regarding those call state control function entities the external entity can subscribe to.", "[0016] Preferably, the notification is sent to the external entity, and the external entity may comprise an application server.", "Specifically, the application server may be presence server.", "The information storage entity may comprise a home subscriber server.", "The call state control function entity may comprise a serving call state control function entity.", "The external entity may comprise a user equipment.", "[0017] Preferably the at least one other entity comprises a user equipment.", "[0018] The communication system may operate in accordance with a session initiation protocol (SIP), and the events are events of that protocol.", "The subscription message may comprise a SIP SUBSCRIBE message, and the notification comprises a SIP NOTIFY message.", "[0019] According to a second aspect of the present invention, there is provided a method for sending notifications in a communication system comprising a multimedia network, an entity that is external to the multimedia network and at least one other entity, the multimedia network including an information storage entity and call state control function entities, the method comprising: subscribing by the external entity to the multimedia network for notifications regarding events associated with the at least one other entity;", "routing of subscription messages from the external entity to at least one call state control function entity based on information stored in said information storage entity;", "storing in storage means associated with said at least one call state control function entity information received in said subscription messages;", "and sending a notification by the call state control function in response to an event defined by said information stored at the storage means.", "BRIEF DESCRIPTION OF DRAWINGS [0020] Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which: [0021] FIG. 1 illustrates a communication system wherein the present invention can be applied;", "[0022] FIG. 2 illustrates one embodiment of the present invention;", "[0023] FIG. 3 illustrates an example of a multimedia network [0024] FIG. 4 illustrates the message flow from an Application Server to the IMS, and from a User Endpoint and the IMS during subscription of events in an embodiment of the present invention;", "and [0025] FIG. 5 illustrates the message flow of another embodiment of the present invention.", "DETAILED DESCRIPTION OF EMBODIMENTS [0026] Reference will now first be made to the FIG. 1 , which illustrates a typical 3 rd Generation (3G) Wireless telecommunications system operating under the Universal Mobile Telecommunications System (UMTS).", "At the hub of this system is the IP Multimedia Subsystem (IMS) 110 network, which routes calls between two or more users of the network.", "Examples of users are mobile terminal 100 of the home network, mobile terminal 122 in a visited mobile network 120 , Public Switched Telephone Network (PSTN) telephone 132 , computer terminal 142 , and application server (AS- 1 ) 144 , such as a presence server, and application server (AS- 2 ) 146 .", "Examples not shown in FIG. 1 may include laptops, personal desktop assistants (PDAs), and other suitably configured devices.", "The IMS uses an IP based network to handle these calls, which may include both voice calls and multimedia calls.", "[0027] The IMS network effectively acts as a gateway in a 3G system between a mobile terminal and other networks such as other mobile networks 120 , PSTN systems 130 , and external IP based networks 140 .", "Signalling between the mobile terminal and other users of the IMS network, and within the IMS network, is done under the Session Initiation Protocol (SIP).", "[0028] Typical nodes between the mobile terminal 100 and the IMS include a base transceiver station (BTS) 102 , a radio network controller (RNC) 104 , a serving GPRS (General Packet Radio Service) support node (SGSN) 106 , and a gateway GPRS support node (GGSN) 108 .", "These are typically referred to collectively as the 3G mobile core network 150 .", "The GGSN acts as the gateway from the mobile core network to the IMS.", "[0029] The 3G mobile core network 150 , the IMS network 110 , and the IP based network 140 are all considered part of the home network of the mobile terminal 100 .", "The mobile terminal 122 is shown communicating with a visited mobile network 120 .", "This network may also operate under a 3G system, in which case it too will have similar elements to those shown in the rest of FIG. 2 , including its own IMS network.", "The link between the home network and the visited network will be at an interface between the home IMS network and the visited IMS network.", "[0030] Reference will now be made to FIG. 2 , which shows a detailed schematic of the home IMS network (IMS 1 ) 110 and the visited IMS network (IMS 2 ) 250 in an embodiment of the present invention.", "IMS 1 includes various elements including several Call State Control Functions (CSCF) 202 , 206 , 208 and 210 , and a Home Subscriber Server (HSS) 204 .", "A CSCF is equivalent to a SIP server in the IETF architecture.", "[0031] The Interrogating CSCF (I-CSCF) 202 is the basic IMS node used for terminating calls in the IMS network, functioning at the edge of the network.", "Here, it is shown communicating with the external nodes of the mobile terminal 100 (indirectly via Proxy-CSCF 210 ), and the application server (AS- 1 ) 144 .", "It should be appreciated that the connections between the mobile terminal and the application server to the I-CSCF may not be direct, but via a suitable intermediate network such as the mobile core network 150 for the mobile terminal, and the Internet 140 for the application server, as shown in FIG. 1 .", "[0032] The Proxy CSCF (P-CSCF) 210 is the first point of call in a visited IMS network.", "Its primary task is to route messages from the visited IMS network to the home IMS network, or more specifically to the I-CSCF before registration has taken place or to the S-CSCF once registration has taken place.", "It also performs a similar role in the home network for a user such as mobile terminal 100 .", "[0033] The S-CSCFs, 206 and 208 , are the IMS nodes responsible for invoking services related to IMS users.", "They also act as the registrars for IMS users, where registrations from users are processed.", "It is therefore the S-CSCFs that detect the specific events subscribed to any associated user, then sends out an appropriate NOTIFY message.", "[0034] Normally the REGISTER message from a user is routed from the P-CSCF to the I-CSCF, which in turn routes it to the appropriate S-CSCF.", "However, during registration the network normally returns the address of the S-CSCF to the P-CSCF.", "Thus, once registration has taken place, subsequent non-REGISTER messages will be routed directly from P-CSCF to S-CSCF.", "[0035] It should be appreciated by those skilled in the art the connections between the elements shown in FIG. 2 are not exhaustive, and others may exist depending on the nature of the messages sent.", "For example, in terminating calls, when calling party's home network (IMS 1 ) connects to called party's home network (IMS 2 ), the connection will normally be made from S-CSCF 206 of calling party towards I-CSCF 254 of called party's IMS network, and not via the P-CSCF.", "This and other similar connections have not been shown for the sake of simplicity.", "[0036] A simplified example of the typical message flow for a SUBSCRIBE from User A to REGISTER messages from User B is as follows: 1.", "S-CSCF in user B's home domain receives a SUBCRIBE to REGISTER events of User B from User A;", "S-CSCF updates its database with this new event package subscription relating to User A, and acknowledges receipt of the SUBSCRIBE message with a 200 OK message;", "User B then sends a REGISTER message to S-CSCF;", "S-CSCF in user B's home domain acknowledges receipt of the REGISTER message with a 200 OK message to User B;", "and then 5.", "S-CSCF in user B's home domain sends a NOTIFY message to User A to inform of the REGISTER message it has just received from User B;", "User A responds with a 200 OK message.", "[0043] Another example of the message flow for a SUBSCRIBE from an application server AS to REGISTER messages from User B is as follows: 1.", "S-CSCF in user B's home domain receives a SUBCRIBE to REGISTER events of User B from AS;", "S-CSCF updates its database with this new event package subscription relating to AS, and acknowledges receipt of the SUBSCRIBE message with a 200 OK message;", "User B then sends a REGISTER message to S-CSCF;", "S-CSCF in user B's home domain acknowledges receipt of the REGISTER message with a 200 OK message;", "and then 5.", "S-CSCF in user B's home domain sends a NOTIFY message to inform AS of the REGISTER message it has just received from User B;", "AS responds with a 200 OK message.", "[0050] What is important in the embodiments of the present invention is that the S-CSCF maintains information on each user's service profile and thus knows which user has services in which AS.", "The S-CSCF also maintains a record of the ASs and the SIP event packages they have subscribed to.", "This means that for any AS used by an IMS user registered to a given S-CSCF, there is information on which SIP events each AS has subscribed to.", "As shown above, this SIP event information is updated whenever the S-CSCF receives a subscription for a SIP event from an AS.", "In effect, this means that an AS can subscribe to all relevant users in the IMS network with just one SUBSCRIBE message.", "[0051] Note that the user information and the AS event subscription information is separated in the S-CSCF's database, which means that the general subscriptions to SIP events, relating to any IMS user, are stored only once per AS.", "[0052] The HSS is a centralised user database that interfaces with both the I-CSCF and the S-CSCF, storing information on all users of the IMS.", "In one embodiment of the present invention, the HSS maintains a database of all external ASs which are allowed to subscribe to SIP events occurring in the IMS network, thereby performing a filter function on the ASs.", "The database contains relevant information on which S-CSCFs in the IMS relates to specific SIP event subscriptions for each AS.", "An example of the database in the HSS is shown in FIG. 3 .", "[0053] In FIG. 3 , the database for AS- 1 , 302 , is shown to include the following entries: AS- 1 SUBSCRIBE to REGISTER events SUBSCRIBE to INVITE events attached S-CSCFs S-CSCF- 1 [0059] Likewise, the database for AS- 2 , 304 , includes the following entries: AS- 2 SUBSCRIBE to REGISTER events attached S-CSCFs S-CSCF- 1 S-CSCF- 2 [0065] Only 2 entries, 302 and 304 , have been shown in this embodiment, but there may be more entries depending on the number of application servers that are in use.", "[0066] The arrangement above means that the list of S-CSCFs connected to the AS must be updated whenever the AS is configured to some user's profile i.e. whenever any user signs up for the services of the AS.", "[0067] However it is important to note that user profile information and the AS information are stored separately in the HSS database.", "[0068] The visited IMS network 250 shown includes similar elements to the home IMS network.", "There is P-CSCF 252 , an I-CSCF 254 , a S-CSCF 256 , and a HSS 258 .", "Also shown is a visiting mobile terminal 122 in communication with the P-CSCF in the visited IMS network.", "This P-CSCF will forward any messages from the mobile terminal 122 back to its home IMS network via I-CSCF 202 or directly to S-CSCF 206 as appropriate.", "[0069] FIG. 4 shows the typical message flow when AS- 1 subscribes to the REGISTER event in one embodiment of the present invention, where the I-CSCF sends the SUBSCRIBE message to S-CSCF directly.", "FIG. 5 shows another embodiment where the HSS is used as a proxy by the I-CSCF for sending the SUBSCRIBE message to the appropriate S-CSCF.", "[0070] The function of the elements in FIG. 2 , in relation to how subscriptions to SIP events are handled in the home IMS network, will now be described in more detail at first with reference to the message flow diagram FIG. 4 , then FIG. 5 .", "[0071] FIG. 4 describes the following process: 1.", "AS- 1 144 sends an SIP ‘SUBSCRIBE to REGISTER events’ message, S 1 , to the IMS, which is handled initially by the I-CSCF 202 .", "This can be done as the IMS address used to direct the message to the IMS should point towards an I-CSCF node for terminating sessions.", "The I-CSCF then queries, S 2 , the HSS for a list of S-CSCFs to which the SUBSCRIBE messages from AS- 1 should be sent to.", "HSS 204 returns a list, S 3 , of all relevant S-CSCFs to I-CSCF.", "In this case it is S-CSCF- 1 206 .", "I-CSCF proxies the SUBSCRIBE message to S-CSCF- 1 , S 4 .", "S-CSCF- 1 receives the SUBSCRIBE and updates this new SIP event package subscription to its database for AS- 1 .", "Information as to the source of the SUBSCRIBE message, in this case AS- 1 , can be found within the message.", "S-CSCF- 1 acknowledges, S 5 , the SUBSCRIBE to the I-CSCF with a ‘200 OK’ message.", "I-CSCF receives the acknowledgement from S-CSCF- 1 and sends a similar acknowledgment, S 6 , to AS- 1 .", "User Endpoint (UE), which in this example is the mobile terminal 122 , sends a REGISTER message, S 7 , to P-CSCF 252 .", "P-CSCF routes, S 8 , this message to I-CSCF 202 .", "I-CSCF queries, S 9 , the HSS for information on which S-CSCF the REGISTER message should be sent to.", "10.", "I-CSCF forwards the REGISTER message, S 10 , to S-CSCF- 1 .", "11.", "S-CSCF- 1 acknowledges the REGISTER with a ‘200 OK’ message, S 11 a, to the I-CSCF which routes it back, S 12 a and S 13 a, to the UE.", "12.", "S-CSCF- 1 checks the service profile of UE to find all ASs associated with it.", "It then checks what subscriptions each of those ASs have made.", "13.", "In this case, S-CSCF- 1 finds that UE is associated with AS- 1 , and that AS- 1 has subscribed to REGISTER events.", "It therefore sends a NOTIFY message, S 11 b, to AS- 1 to inform it of this occurrence.", "14.", "AS- 1 acknowledges with a ‘200 OK’ message, S 12 b. This acknowledgment may contain additional information on the success of the subscription.", "[0086] FIG. 5 describes a similar process to FIG. 4 , but here the I-CSCF uses the HSS to proxy the S-CSCF on its behalf, rather than doing so directly.", "The process is therefore identical except for steps S 2 to S 5 of FIG. 4 , which are effectively replaced by steps T 2 to T 5 in FIG. 5 .", "Steps T 2 to T 5 will now be discussed in further detail below: 1.", "When I-CSCF receives the SUBSCRIBE message, T 1 , from AS- 1 , it proxies the message, T 2 , to the HSS.", "The HSS looks up in its list which S-CSCFs the SUBSCRIBE message should be sent to, in this case S-CSCF- 1 , and in turn proxies the SUBSCRIBE message, T 3 , to S-CSCF- 1 .", "S-CSCF- 1 receives the SUBSCRIBE message and updates this new event package to its database for AS- 1 , and sends an acknowledgment, T 4 , to HSS, which proxies it back, T 5 , to the I-CSCF.", "[0090] The remaining processes from T 6 to T 12 b are the same as the numerical equivalents S 6 to S 12 b. [0091] One advantage of embodiments of the present invention is that any external network node, such as application servers, user equipment, or any other user operating under SIP, may approach the IMS network as if it were a standalone SIP server.", "As a result, external nodes may use the IMS address of an IMS entity (e.g. IMS user or IMS ‘registrar’) and send any SIP event subscriptions to IMS without needing to know the internal architecture of the IMS network.", "This is an important advantage as otherwise the AS would have to know precisely which user is served by which S-CSCF before it sending its subscriptions.", "A further benefit of hiding the internal structure of the IMS is provided for operators who do not want their competitors gaining knowledge of their proprietary architecture.", "[0092] Another advantage is that with a single SUBSCRIBE message, an AS can subscribe to events associated with a plurality or all the relevant users in the IMS network without requiring one message per user as previously.", "This may simplify subscription management in the AS significantly.", "Consequently, as the IMS elements only need to store one subscription per AS and not separate data relating to each and every user to the AS, considerable savings in storage requirements may be gained, in particular at entities such as the HSS and S-CSCF.", "[0093] The embodiments also provide for greater flexibility in the addressing of the AS, allowing for multiple addresses per AS.", "This means that a single AS can present itself to the IMS with different addresses, which allows for a variety of event subscription schemes between different IMS users.", "[0094] It should be appreciated that the IMS network 110 may also comprise further S-CSCFs and Proxy CSCFs (P-CSCF).", "Likewise, although embodiments of the present invention have been described in the context of 3G using SIP, other suitable systems and interface protocols could be used.", "[0095] It is also noted herein that while the above describes exemplifying embodiments of the invention, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention as defined in the appended claims." ]
CROSS REFERENCE TO RELATED APPLICATION This application is a divisional of U.S. patent application Ser. No. 09/786,022 filed Nov. 9, 2001, now U.S. Pat. No. 6,630,698, which was the National Stage of International Application No. PCT/DE99/01218, filed Apr. 22, 1999. TECHNICAL FIELD The present invention concerns a semiconductor device with a semiconductor body having a blocking pn-junction, a first zone of a first conductivity type, which is connected to a first electrode and abuts one of the zones of a second conductivity type opposite the first conductivity type forming the blocking pn-junction, and with a second zone of the first conductivity type, which is connected to a second electrode, whereby the side of the zone of the second conductivity type facing the second zone forms a first surface and in the region between the first surface and a second surface, which lies between the first surface and the second zone, areas of the first and of the second conductivity type are nested. BACKGROUND OF THE INVENTION Such semiconductor devices are also known as compensation devices. Such compensation devices are, for example, n- or p-channel MOS field effect transistors, diodes, thyristors, GTOs, or other components. In the following, however, a field effect transistor (also referred to briefly as “transistor”) is assumed as an example. There have been various theoretical investigations spread over a long period of time concerning compensation devices (cf. U.S. 4,754,310 and U.S. 5,216,275) in which, however, specifically, improvements of the on-resistance RDS(on) but not of stability under current load, such as, in particular, robustness with regard to avalanche and short circuit in the high-current operation with high source-drain voltage, are sought. Compensation devices are based on mutual compensation of the charge of n- and p-doped areas in the drift region of the transistor. The areas are spatially arranged such that the line integral above the doping along a line running vertical to the pn-junction in each case remains below the material-specific breakdown voltage (silicon: approximately 2×10 12 cm −2 ). For example, in a vertical transistor, as is customary in power electronics, p-and n-columns or plates, etc. may be arranged in pairs. In a lateral structure, p- and n-conductive layers may be stacked on each other laterally alternating between a groove with a p-conductive layer and a groove with an n-conductive layer (cf. U.S. Pat. No. 4,754,310). By means of the extensive compensation of the p- and n-doping, the doping of the current-carrying region (for n-channel transistors, the n-region; for p-channel transistors, the p-region) can be significantly increased, whereby, despite the loss in current-carrying area, a clear gain in on-resistance R DS (on) results. The blocking capability of the transistor depends substantially on the difference between the two dopings. Since, because of the reduction of the on-resistance, a doping higher by at least one order of magnitude of the current-carrying area is desirable, control of the blocking voltage requires controlled adjustment of the compensation level, which can be defined for values in the range ≦±10%. With a greater gain in on-resistance, the range mentioned becomes even smaller. The compensation level is then definable by (p-doping-n-doping)/n-doping or by charge difference/charge of one doping area. Other definitions are, however, possible. SUMMARY OF THE INVENTION It is an object of the present invention to provide a robust semiconductor component of the kind initially mentioned, to be firstly distinguished by a high “avalanche” ruggedness and high current load capacity before and/or during breakdown and secondly simple to produce with reproducible properties in view of technological latitudes of fluctuation of manufacturing processes. This object is accomplished according to the invention, in a semiconductor component of the kind initially mentioned, in that the regions of the first and second types of conductivity are so doped that charge carriers of the second conductivity type predominate in regions near the first surface and charge carriers of the first conductivity type in regions near the second surface. Preferably, the regions of the second conductivity type do not extend as far as up to the second zone, so that between said second surface and the second zone, a weakly doped region of the first conductivity type remains. It is possible, however, to allow the width of this region to go to “zero.” The weakly doped region, however, provides certain advantages, such as enhancement of the barrier voltage, “smooth” profile of the electrical field strength, or improvement of commutation properties of the inverse diode. In another refinement of the invention, it is provided that between the first and second surfaces, a degree of compensation effected by the doping is so varied that atomic residues of the second conductivity type dominate near the first surface and atomic residues of the first conductivity type near the second surface. In other words, there are sequences of p, p − , n − , n or n, n − , p − , p layers between the two surfaces. Advantageous improvements of the semiconductor device according to the invention (hereinafter also referred to as “compensation device”) are disclosed by the other dependent claims. The effect of the areas nested in each other, alternating different conductivity types, on the electrical field, is, in contrast to a conventional DMOS transistor, for example, as follows (“lateral” and “vertical” refer in the following to a vertical transistor): (a) There is a cross-field, “lateral” to the direction of the connection between the electrodes, the strength of which depends on the proportion of the lateral charge (line integral perpendicular to the lateral pn-junction) relative to the breakdown charge. This field leads to the separation of electrons and holes and to a reduction in the current-carrying cross-section along the current paths. This fact is of primary significance for the understanding of the processes in avalanche, of the breakdown characteristic curve, and of the saturation region of the output characteristics diagram. (b) The “vertical” electrical field parallel to the direction of the connection between the electrodes is determined locally by the difference between the adjacent dopings. This means that with an excess of donors (n-loaded distribution: the charge in the n-conductive areas exceeds the charge of the p-areas) on the one hand, a DMOS-like field distribution (maximum of the field on the blocking pn junction, decreasing field in the direction of the opposing back of the device) appears, whereby the gradient of the field is, however, clearly less than would correspond to the doping of the n-area alone. On the other hand, however, by overcompensation of the n-conductive area with acceptors, a field distribution rising in the direction of the back is possible (p-loaded distribution: excess of acceptors compared to the donors). In such a design, the field maximum lies at the bottom of the p-area. If the two dopings are exactly compensated, there is a horizontal field distribution. With an exact horizontal field distribution, the maximum of the breakdown voltage is obtained. If the acceptors or the donors predominate, the breakdown voltage drops in each case. If the breakdown voltage is then plotted as a function of the degree of compensation, a parabolic characteristic is obtained. Constant doping in the p- and n-conductive areas or even a locally varying doping with periodic maxima of equal height results in a comparatively sharply pronounced maximum of the “compensation parabola”. For the benefit of a “production window” (including the fluctuations of all relevant individual processes), a comparatively high breakdown voltage must be steered for in order to obtain reliable yields and production reliability. Consequently, the objective must be to make the compensation parabola as flat and as broad as possible. When the blocking voltage is applied to the device, the drift region, i.e., the region of the areas of opposite doping arranged in pairs, is cleared of mobile charge carriers. The positively charged donor cores and the negatively charged acceptor cores remain in the spreading space charge region. They then determine the course of the field. The flow of current through the space charge region causes a change in the electric field when the concentration of the charge carrier associated with the flow of current comes into the region of the background doping. Electrons compensate donors; holes compensate acceptors. For the stability of the device, it is also very important which doping predominates locally, where charge carriers are generated, and how their concentrations result along their current paths. For the following embodiments, for an understanding of the basic mechanism, initially a constant doping of the p- and n-conductive areas is assumed. In the on-state and especially in the saturation region of the output characteristics of a MOS transistor, a pure stream of electrons flows from the channel into an n-doped area, also referred to as a “column” in a vertical transistor, whereby in the base an increasing focusing of the flow of current occurs because of the electrical cross-field. High-current stability is promoted by dominance of the n-doping; however, since the channel region with its positive temperature coefficient eliminates inhomogeneous current distribution in a cell field, this mode of operation is rather uncritical. Reduction in the current density is obtained through partial shadowing of the channel connection (cf. DE 198 08 348 A1). With regard to the breakdown characteristic or its course, the following must be taken into consideration: The generation of electrons and holes occurs in the region of maximum field strength. The separation of the two types of charge carriers is performed by the electrical cross-field. Along the two current paths in the p- and n-area, respectively, focusing and further multiplication occurs. Ultimately, also no effect of a partial channel shadowing occurs. Stability is present only when the mobile charge carriers cause a rise in the electrical field outside their source and thus a rise in the breakdown voltage of the respective cell. For compensation devices this means stability in the p- and n-loaded region, but not in the maximum of the compensation parabola. In the p-loaded region, the breakdown occurs at the “bottom” of the column. The electrons flow out of the drift region and thus do not affect the field. The holes are pulled through the longitudinal electrical field to the top source contact. In the process, the hole current is focused along its path by the electrical cross-field: The current density rises here. Thus, the longitudinal electrical field is initially affected near the surface. As a result of compensation of the excess acceptor cores (p-loaded distribution), a reduction in the gradient of the electrical field and a rise in the breakdown voltage occur. This situation is stable as long as the field there remains clearly below the critical field strength (for silicon: approximately 270 kV/cm for a charge carrier concentration of approximately 10 15 cm −3 ). In the n-loaded region with an excess of donors, the breakdown is near the surface. The holes flow to the source contact and still affect the field on their path from their source to the p-well. The objective must consequently be to place the breakdown location as near as possible to the p-well. This can be accomplished, for example, by a local elevation in the n-doping. The electrons flow through the complete drift zone to the back and likewise affect the field along their current path. Stability is obtained when the effect of the electron current prevails over that of the hole current. Since the geometry of the cell arrangement plays an important role here, there is a region of stable and instable characteristic curves especially near the maximum of compensation parabola. The conditions in the avalanche are very similar to those of a breakdown. The currents are, however, clearly higher and have with a rated current as much as twice the rated current of the transistor. Since the electrical cross-field always causes a clear focusing of the current, in compensation devices the stability range is left at comparatively low current loads. Physically, this means that the current-induced rise in the field has already advanced so much that locally the breakdown field strength has been reached. The longitudinal electrical field can then not rise further locally; the curvature of the longitudinal electrical field, however, increases which results in a drop in the breakdown voltage of the cell in question. In the characteristic curve of an individual cell and also in the simulation, this is reflected by a negative differential resistance; i.e., the voltage drops as the current rises. In a large transistor with more than 10,000 cells this results in a very rapid inhomogencous redistribution of the current. A filament is formed, and the transistor melts locally. This yields the following consequences for the stability of compensation devices: (a) Due to the separation of electrons and holes there is no “auto-stabilization” as with IGBTs and diodes. Instead, the degree of compensation, field distribution, and breakdown location must be set exactly. (b) On the compensation parabola, with constant doping of the p- and n-areas or “columns”, there are stable regions in the clearly p- and in the clearly n-charged regions. The two regions are not contiguous. Thus, there is only an extremely small production window. With constant doping of the p- and n-areas or columns, the compensation parabola is extremely steep. The breakdown location moves within a few percent from the bottom of the p-column in the direction of the surface. (c) For each compensation device, there is a current destruction threshold in the avalanche which is directly coupled with the degree of compensation. The degree of compensation, on the other hand, determines the achievable breakdown voltage and effects the R DS (on) gain. (d) With constant doping of the p- and n-areas, the devices are—as mentioned above—instable near the maximum of the compensation parabola. This results in the fact that the devices with the highest blocking voltage are destroyed in the avalanche test. As explained above, to prevent the disadvantages, the degree of compensation is varied along the doping areas, i.e., in a vertical structure from the top in the direction of the back of the transistor, such that the atomic cores of the second conductivity type dominate near the surface and the atomic cores of the first conductivity type dominate near the back. The resultant field distribution has a “hump-shaped” curve with a maximum at approximately one-half of the depth(cf. FIG. 6 ). Thus, both the electrons and holes affect the field distribution in the breakdown and in the avalanche. Both types of charge carriers have a stabilizing effect, since in each case they run from their source into areas in which they compensate the dominating excess background doping. There is thus a continuous stability range from p-loaded to n-loaded degrees of compensation. A variation of the degree of compensation due to production fluctuations shifts the breakdown location only slightly in the vertical direction and continuously back and forth, as long as this variation is less than the technically adjusted variation of the degree of compensation. The size of this modification of the degree of compensation also determines the limits of the stability range. Thus, the production window becomes freely selectable. The focusing of the currents is clearly less pronounced since both types of charge carriers travel only one-half the path in the region of the compressing electrical cross-field. Thus, the devices can be stressed with clearly higher currents in the avalanche. Since in a variation of the degree of compensation, e.g., in the direction toward “n-loading”, the electrical field increases in each case in the upper area of the drift region, but simultaneously decreases in the lower area (vice versa with variations toward p-loaded distribution), the breakdown voltage varies only relatively little as a function of the degree of compensation. Thus, the compensation parabola becomes preferably flat and wide. The vertical variation of the degree of compensation can be effected by variation of the doping in the p-region or by variation of the doping in the n-region or by variation of the doping in both regions. The variation of the doping along the column may have a constant rise or be in a plurality of steps. In principle, the variation increases monotonically from a p-loaded degree of compensation to an n-loaded degree of compensation. The invention can be readily applied even with p-channel transistors. In that case, an appropriately altered course of the semiconductor regions occurs: A (p, p-dominated, n-dominated, n) course is replaced by an (n, n-dominated, p-dominated, p) course. The stability limits are reached on the n-loaded side when the field runs horizontally near the surface over an appreciable part of the drift region. On the p-loaded side the stability limits are reached when the field runs horizontally near the bottom of the compensating column region over a noticeable part of the drift region. In general, the compensation parabola becomes flatter and wider the greater the gradient of the degree of compensation. The breakdown voltage in the maximum of the compensation parabola drops accordingly. Another important limitation of the variation of the degree of compensation results from the requirement to remain below the breakdown charge. In addition, with greater elevation of the p-column doping near the surface, current pinch-off effects occur near the surface (lateral JFET effect). For 600 V devices, a variation of the degree of compensation lengthwise of the p- and n-areas of 50%, for example, is advantageous. Although above the starting point has been primarily a vertical transistor, the semiconductor device according to the invention can, in principle, have a vertical or even a lateral structure. With a lateral structure, n- and p-conductive plate-shaped areas are, for example, arranged laterally stacked in each other. Applications for such lateral transistors are, for example, found in the smart power sector or in microelectronics; vertical transistors are, in contrast, produced primarily in power electronics. The vertical modification of the degree of compensation is very simple to implement since in the individual epitaxial planes, only the implantation dose must be altered. The “real” compensation dose is then implanted in the middle epitaxial layer; below that, for example, 10% less in each case, above that, for example, 10% more in each case. However, instead of the implantation dose, it is possible to alter the epitaxial doping. By means of the more manageable variation, it is possible to reduce the production costs. The number of necessary epitaxial layers can be reduced, and the openings for the compensation implantation can be reduced as a result of greater variation of the implanted dose due to the greater relative variation of the resist dimension with simultaneously prolonged subsequent diffusion for the merging of the individual p-regions into the “column”. The structure according to the invention is produced by the following individual steps: First, a multi-μm-thick, n-doped epitaxial layer is applied to a semiconductor substrate. The p-doping ions are introduced into this epitaxial layer via a resist mask by means of ion implantation. Next, the entire process is repeated as often as necessary until there is an adequately thick n-multi epitaxial layer with embedded p-centers aligned with each other and stacked. The production of the actual device then occurs, by means of, for example, the processing of the base zones, the source zones, the front metalization, and the gate electrodes in a field effect transistor. By thermal diffusion, the p-doped centers merge into a rippled vertical column. Due to intrinsic compensation, the concentration of the p- or n-doping material is always substantially higher than the resultant electrically active doping. The ripple of the vertical column is expressed in a varying acceptor-donor ratio k c (z) per horizontal plane. The electrical compensation varies accordingly in each horizontal plane in the semiconductor body. The ripple of the column causes no significant change in the horizontal field. Consequently, in the first approximation, the contribution U Bh is considered unaffected by the ripple. In the vertical direction, layers with non-horizontally compensated p-and n-charges alternate. An epitaxial layer corresponds to a complete ripple period and, consequently, corresponds to two adjacent pn-junctions. Due to the production fluctuations in the epitaxy cycles, the charge balance is not equalized over the entire volume of a pn-junction such that the degree of compensation does not equal 0. In a semiconductor device according to the present invention, the voltage consumed in the blocked state in the cell field between anodes and cathodes or in a field effect transistor vertically between source and drain must also be discharged laterally on the edge of the semiconductor device. Semiconductor devices are often operated up to a breakdown. In this case, a very high current flows through the impact ionization which occurs. In order not to destroy the semiconductor device, no excessively high current densities may occur, i.e., the breakdown current must be distributed as uniformly as possible over the entire semiconductor device. However, this requirement can be fulfilled only if the cell field carries the majority of this current. If the semiconductor device breaks down in the edge structure at a smaller blocking voltage than the cell field, this results in most cases in irreversible thermal damage to the semiconductor device. The semiconductor device must, consequently, be avalanche-rugged. Avalanche-rugged semiconductor devices, especially vertical transistors, reduce the safety distance necessary to manage overvoltages, whereby in many applications comparatively low-blocking transistors may be used, which require at the same R DS (on) a comparatively small semiconductor device surface and are thus more economical. With conventional high-voltage MOSFETs, this is very significant since the R DS (on) of these transistors rises disproportionately with the breakdown voltage. With conventional power devices, expensive surface-mounted structures or structures near the surface usually result in the situation that the semiconductors device edge can block more voltage than the cell field. The lower-lying semiconductor device volume is homogeneously doped so low that it withstands the necessary voltage without structuring. With the semiconductor devices according to the present invention, which use the production process of intrinsic compensation, the demands with regard to the edge structure are intensified because here even the lower-lying volumes under the edge must be processed. The material actually accommodating the blocking voltage, i.e., the epitaxial layer above the highly doped semiconductor substrate, is relatively low ohmic and will only block a fraction of the required voltage. The blocking capability for the cell field is achieved only with the introduction of the counter doped columns. For the volume below the edge, there are, in principle, two different processing methods: 1. The semiconductor edge may be processed separately from the cell field, i.e., in additional steps. An overall counter doping of the substrate on the semiconductor edge, e.g., by means of overall edge implantation and diffusion, is conceivable. Thus, an overall intrinsically compensated and thus highly blocking edge can be produced. Such a procedure is, however, associated with very high costs. 2. The column structure in the cell field is continued into the edge, whereby the substrate is also built up to basically the same blocking voltages as in the cell field. A minimal increase, for example, in the dielectric strength of the edge may be obtained in many cases by means of a suitable variation of the deep compensation profile of the columns, as this has been described on the preceding pages for the cell field, whereby, however, the tolerance range compared to the cell field and thus the tolerance range of the entire semiconductor device becomes smaller. Additionally, additional effects may provoke breakdown on the edge of the semiconductor device. On the one hand, the surface-mounted edge structures or structures near the surface cause additional field distortions and generate centers of high field strength. On the other hand, it may be necessary to apply an expedient negative “error charge” to the edge, which causes a curvature of the equipotential lines toward the semiconductor device surface, whereby these can be picked up and carried by the surface structure. This corresponds to a field discharge on the semiconductor device edge. This error charge condition may also cause a voltage-induced premature breakdown of the semiconductor device edge compared to the cell field. Accordingly, it is best to reduce the horizontal components of electric field and simultaneously the vertical ripple of the compensation profile on the edge. Both result in higher blocking voltages on the semiconductor device edge. To implement this, the local separation must be eliminated or at least weakened in the charge centers of opposing polarity, i.e., an intrinsic compensation must be undertaken. Thus, a high-voltage resistant edge structure is created, which consists of a plurality of floating zones of the second conductivity type, which are separated by intermediate zones of the first conductivity type, whereby the width of the intermediate zones and width of the floating zones are smaller than the width of the areas of the first and of the second conductivity type, which are nested in each other inside the cell fields. These floating zones and intermediate zones are doped such that the charge carriers of floating zones and of intermediate zones are completely cleared with the application of blocking voltage. Thus, preferably, the edge volume is processed in one and the same operation, whereby both the thickness of an individual epitaxial layer and the cell grid is reduced in size in the edge region, yielding at the end of the process homogeneous dopant distribution for both types of charge carriers for each edge cell. With regard to the ratio of unmasked surface per cell to the total cell surface in the edge region, the charge applied by implantation can be ideally adapted to the charge which is defined by the epitaxy. In order to achieve ideal blockability, a charge balance, i.e., intrinsically compensated condition, is sought. Preferably, the thickness of the individual epitaxial layers will be designed according to specifications which the cell field defines. This again yields a vertically rippled compensation profile on the semiconductor edge, but in a substantially weaker form than in the cell field. A reduction in the cell grid results in the fact that the resolution of the doping material source is reduced, whereby the boundaries of the individual diffusion fronts become blurred. An additional advantage of the edge design described is the coupling between the production defects in the edge and in the cell field since error mechanisms act in both regions in the same direction. BRIEF DESCRIPTION OF THE DRAWINGS The invention is explained in detail in the following with reference to the drawings. They depict: FIG. 1 a top view of an n-channel lateral MOS transistor according to a first exemplary embodiment of the invention, FIG. 2 a cross-section of an n-channel lateral MOS transistor with V-shaped grooves according to a second exemplary embodiment of the invention, FIGS. 3 a through 3 d various layouts in the semiconductor device according to the invention, FIG. 4 a cross-section through an n-channel lateral MOS transistor according to a third exemplary embodiment of the invention, FIG. 5 the course of the degree of compensation K along the line C-D in FIG. 4 , FIG. 6 the course of the electrical field along the line C-D in FIG. 4 , FIG. 7 the course of the breakdown voltage as a function of the degree of compensation for constant doping and for variable doping, FIG. 8 a concrete example of the cell design for an n-channel MOS transistor, FIGS. 9 a through 9 c various square edge structure layouts in the semiconductor device according to the invention, FIGS. 10 a through 10 c various strip edge structure layouts in the semiconductor device according to the invention, FIG. 11 a hexagonal edge structure layout in the semiconductor device according to the invention, FIG. 12 a cross-section through an n-channel MOS transistor according to a fourth exemplary embodiment with an edge structure layout, and FIG. 13 a cross-section through an n-channel MOS transistor according to a fifth exemplary embodiment with a different edge structure layout. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 depicts a top view of an n-channel MOS transistor with an n + -conductive drain zone 15 , an n + -conductive source zone 16 , a gate electrode 8 , and a p-conductive area 5 . This p-conductive area 5 extends finger-like into an n-conductive area 4 on a semiconductor substrate 1 , such that the areas 4 and 5 are “nested” in each other. The gate electrode 8 may, for example, be made of polycrystalline silicon, whereas an isolation layer not shown in FIG. 1 below this gate electrode 8 is made, for example, of silicon dioxide and/or silicon nitride. In the p-conductive area 5 , a p-charge excess is present in a zone I; a “neutral” charge, in a zone II; an n-charge excess, in a zone III. This means that in the area 5 in the zone I, the p-charge dominates the charge of the surrounding n-conductive area 5 ; that also in the zone II, the p-charge exactly compensates the charge of the surrounding n-conductive area 5 ; and that in the zone III, the p-charge is less than the charge of the surrounding n-conductive area 5 . It is thus significant that the charge of the p-area 5 is variable whereas the charge of the n-areas 4 is in each case constant. The p-conductive area 5 extends from the edge of the source zone 16 , i.e. from a surface A to a dashed line surface B in the n-conductive region 4 . This surface B is positioned at a distance from the drain zone 15 , such that there is, between the surface B and the drain zone 15 , an n-conductive region 13 in which there is no “nesting” with p-conductive regions 5 . However, it is also possible to shift the surface B to the edge of the drain zone 15 , such that there is no n-conductive region 13 . Advantageously, however, the surface B is positioned at a distance from the drain electrode 15 , which results in an increase of the blocking voltage, a smoother course of the electrical field, and an improvement of the commutating characteristics of the inverse diode. FIG. 2 depicts a cross-section through another exemplary embodiment of the semiconductor device according to the invention in the form of an n-channel MOS transistor with a drain electrode 2 and a gate insulation layer 9 between the gate electrode 8 and the channel region, which is provided under the insulation layer 9 between a source zone 16 and a drain zone 15 in a p-conductive region 5 . Also, in this exemplary embodiment, the p-conductive areas 5 in the zones I, II, and III have variable doping, as was explained above with reference to FIG. 1 . The exemplary embodiments of FIGS. 1 and 2 depict two preferred design possibilities for lateral structures of the semiconductor device according to the invention. Essential in the two structures is the fact that the reported variable doping is present in the areas 5 and that these areas 5 do not reach the drain zone 15 , i.e., terminate in a surface B at a distance from this drain zone 15 . However, it is possible to move the surface B toward the edge of the drain zone 15 . As stated above, the degree of compensation can be obtained by variation of the doping of the p-conductive areas 5 or of the n-conductive areas 4 . FIGS. 3 a through 3 d depict various layouts for the semiconductor device according to the invention with hexagonal polysilicon structures 17 and polysilicon openings 18 ( FIG. 3 a ), in which aluminum contact holes 19 ( FIG. 3 b ) may be provided. FIG. 3 c depicts a layout with rectangular polysilicon structures 20 and corresponding polysilicon openings 18 and aluminum contact holes 19 , whereas FIG. 3 d schematically depicts, in a top view and in cross-section, a strip structure with polysilicon gate electrodes 8 and aluminum electrodes 21 . FIGS. 3 a through 3 d depict how the semiconductor device according to the invention can be designed with different structures. FIG. 4 depicts a cross-section through an n-channel MOS transistor with an n + -conductive silicon semiconductor substrate 1 , a drain electrode 2 , a first n-conductive layer 13 , the second layer 3 with n-conductive areas 4 and p-conductive areas 5 , p-conductive zones 6 , n-conductive zones 7 , gate electrodes 8 made, for example, from polycrystalline silicon or metal, which are embedded in an isolating layer 9 made, for example, from silicon dioxide, and a source metalization 10 made, for example, from aluminum. Here again, the p-conductive areas 5 do not reach the n + -conductive semiconductor substrate. For the sake of clarity, FIG. 4 depicts only the metal layers hatched, although the remaining areas or zones are also depicted in cross-section. In the p-conductive areas 5 , there is a p-charge excess in a zone I, a “neutral” charge in the zone II, and an n-charge excess in zone III. This means that in the area 5 which forms a “p-column” in the zone I, the charge of the p-column dominates the charge of the surrounding n-conductive area 5 , further that in the zone II, the charge of the p-column precisely compensates the charge of the surrounding n-area 5 , and that in the zone III, the charge of the p-column does not yet dominate the charge of the surrounding n-area 5 . It is also essential that the charge of the p-areas 5 is variable, whereas the charge of the n-areas 4 is in each case constant. However, it is possible here, as in the preceding exemplary embodiments, that the charge of the p-conductive areas 5 is constant and the charge of the n-conductive areas is varied. It is likewise possible to design the charge variable in both areas 4 and 5 . FIG. 5 depicts in a cross-section C-D the course of the degree of compensation K over the depth t of the n-channel MOS transistor: As is discernible from FIG. 5 , the degree of compensation K rises monotonically with a constant gradient or in steps from the point C to point D. It is discernible from FIG. 6 that the electrical field E has a substantially constant curvature over the area 5 between the points C and D. FIG. 7 depicts compensation parabolas for a constant and a variable doping of the p-conductive areas 5 in the exemplary embodiment of FIG. 4 . The degree of compensation K is plotted in percentages on the abscissa, whereas the ordinate indicates the breakdown voltage U in volts. One curve 11 depicts the breakdown voltage U for a variable doping, whereas a curve 12 depicts the breakdown voltage for a constant doping. It is clear that the variable doping brings a considerable drop in the breakdown voltage from approximately 750 V to approximately 660 V. However, in exchange, a larger range of the degree of compensation can be used. FIG. 8 depicts finally a cell design in a cross-section with a drain D, a source S, and a gate G, the n + -conductive semiconductor substrate 1 , an n-conductive semiconductor region 13 , the n-conductive layer 3 , and n-conductive regions 4 as well as p-conductive regions 5 for the p-conductive region 5 under the source electrode S. In FIG. 8 the degrees of compensation, for example, between +30% and −20% are reported, whereby a degree of compensation “0” indicates true compensation between n-doping and p-doping. Here, the doping thus varies within the “p-column” by a factor 3 whereas the doping in the “n-columns” is constant. FIGS. 9 a through 9 c depict, in principle, as in FIGS. 3 a through 3 d , how the semiconductor device according to the invention can be designed with different structures which extend into the edge region. As can be discerned in FIGS. 9 a through c , FIGS. 10 a through c and in FIG. 11 , in the semiconductor edge region, a large number of floating zones 5 ′, are formed from the second conductivity type and are separated from intermediate zones 4 ′ of the first conductivity type. The width of the intermediate zones 4 ′ and the widths of the floating zones 5 ′ are smaller than the widths of the regions 4 , 5 inside the cell field. The floating zones 5 ′ and the intermediate zones 4 ′ are dimensioned such that their charge carriers are completely cleared with the application of blocking voltage. The zones 5 ′, which are designed lightly p-doped in the present exemplary embodiment, are “floating”, i.e., they have an undefined potential. The floating zones 5 ′ are positioned at a distance from each other, whereby the region between the floating zones 5 ′ defines an intermediate zone 4 ′. This intermediate zone 4 ′ typically has the same doping concentration as the doping in the zones 4 within the cell field. FIGS. 9 a, b, and c depict different variations of the widths of the floating zones compared to the basic widths in the cell field. FIGS. 10 a, b, and c depict the same thing with the strip edge structure layout and FIG. 11 with a hexagonal edge structure layout. FIG. 12 and FIG. 13 depict the n-channel MOS transistor known from FIG. 4 , which has been expanded by an intrinsically compensated edge termination. The transistor is built in known fashion with an n + -conductive silicon semiconductor substrate 1 , a drain electrode 2 , a first n-conducting layer 13 , a second layer with n-conducting areas 4 and p-conductive areas 5 , p-conductive zones 6 , n-conductive zones 7 , gate electrodes 8 made, for example, from polycrystalline silicon or metal, which are embedded in an insulation layer 9 made, for example, from silicon dioxide, and a source metalization 10 made, for example, of aluminum. In the present figures in each case two p-conductive areas 5 and n-conductive areas 4 are depicted on the left side. Toward the right, additional p-conductive areas 5 ′ and n-conductive areas 4 ′ extend alternatingly. The p-conductive areas 5 ′ have, compared to the p-conductive areas 5 , roughly half the width; however, they extend roughly as far into the n-conductive region 13 in the direction of the substrate 1 . The regions 5 ′, 4 ′ lying adjacent the regions 4 , 5 are connected to a p-conductive zone 6 ′, which connects via a contact hole with the source metalization 10 . The p-conductive zone 6 ′ forms a p-ring known from the prior art. The p-conductive zones 6 ′ has, in contrast to the cell field, no n-conductive zone, to prevent parasitic transistors. The n- and p-conductive areas 4 ′, 5 ′ extend far beyond the p-conductive zone 6 ′ in the direction of the edge of the device. On the outermost edge, there is a so-called channel stopper configuration, which consists of a gate electrode 8 ′, which is electrically connected with an n-conductive zone 7 ″, which for its part is accommodated in a p-conductive zone 6 ″ in the n-conductive region 13 . The so-called space charge region stopper depicted in FIG. 13 constitutes an alternative to the channel stopper configuration depicted in FIG. 12 . This space charge region stopper consists only of a well conductive n + -conductive zone, which is placed in the n-conductive region. Common to both exemplary embodiments is the fact that the contact holes of the p-conductive zone 6 ′ are substantially larger compared to the contact holes in the n- or p-conductive zones 7 , 6 . The result of this is that the gate electrode 8 ′, which lies above the areas 4 ′, 5 ′ is designed substantially smaller compared to the gate electrodes 8 of the cell field. The grid, in which the areas 4 ′, 5 ′ are arranged, is roughly half as large as the areas 4 , 5 of the cell field.
A semiconductor component has a semiconductor body comprising a blocking pn junction, a source zone of a first conductivity type connected to a first electrode and bordering on a zone forming the blocking pn junction of a second conductivity type complementary to the first conductivity type, and a drain zone of the first conductivity type connected to a second electrode. The side of the zone of the second conductivity type facing the drain zone forms a first surface, and in the region between the first surface and a second surface located between the first surface and the drain zone, comprises areas of the first and second conductivity type nested in one another. The second surface is positioned at a distance from the drain zone such that the areas of the first and second conductivity type nested in each other do not reach the drain zone.
Summarize the key points of the given document.
[ "CROSS REFERENCE TO RELATED APPLICATION This application is a divisional of U.S. patent application Ser.", "No. 09/786,022 filed Nov. 9, 2001, now U.S. Pat. No. 6,630,698, which was the National Stage of International Application No. PCT/DE99/01218, filed Apr. 22, 1999.", "TECHNICAL FIELD The present invention concerns a semiconductor device with a semiconductor body having a blocking pn-junction, a first zone of a first conductivity type, which is connected to a first electrode and abuts one of the zones of a second conductivity type opposite the first conductivity type forming the blocking pn-junction, and with a second zone of the first conductivity type, which is connected to a second electrode, whereby the side of the zone of the second conductivity type facing the second zone forms a first surface and in the region between the first surface and a second surface, which lies between the first surface and the second zone, areas of the first and of the second conductivity type are nested.", "BACKGROUND OF THE INVENTION Such semiconductor devices are also known as compensation devices.", "Such compensation devices are, for example, n- or p-channel MOS field effect transistors, diodes, thyristors, GTOs, or other components.", "In the following, however, a field effect transistor (also referred to briefly as “transistor”) is assumed as an example.", "There have been various theoretical investigations spread over a long period of time concerning compensation devices (cf.", "U.S. 4,754,310 and U.S. 5,216,275) in which, however, specifically, improvements of the on-resistance RDS(on) but not of stability under current load, such as, in particular, robustness with regard to avalanche and short circuit in the high-current operation with high source-drain voltage, are sought.", "Compensation devices are based on mutual compensation of the charge of n- and p-doped areas in the drift region of the transistor.", "The areas are spatially arranged such that the line integral above the doping along a line running vertical to the pn-junction in each case remains below the material-specific breakdown voltage (silicon: approximately 2×10 12 cm −2 ).", "For example, in a vertical transistor, as is customary in power electronics, p-and n-columns or plates, etc.", "may be arranged in pairs.", "In a lateral structure, p- and n-conductive layers may be stacked on each other laterally alternating between a groove with a p-conductive layer and a groove with an n-conductive layer (cf.", "U.S. Pat. No. 4,754,310).", "By means of the extensive compensation of the p- and n-doping, the doping of the current-carrying region (for n-channel transistors, the n-region;", "for p-channel transistors, the p-region) can be significantly increased, whereby, despite the loss in current-carrying area, a clear gain in on-resistance R DS (on) results.", "The blocking capability of the transistor depends substantially on the difference between the two dopings.", "Since, because of the reduction of the on-resistance, a doping higher by at least one order of magnitude of the current-carrying area is desirable, control of the blocking voltage requires controlled adjustment of the compensation level, which can be defined for values in the range ≦±10%.", "With a greater gain in on-resistance, the range mentioned becomes even smaller.", "The compensation level is then definable by (p-doping-n-doping)/n-doping or by charge difference/charge of one doping area.", "Other definitions are, however, possible.", "SUMMARY OF THE INVENTION It is an object of the present invention to provide a robust semiconductor component of the kind initially mentioned, to be firstly distinguished by a high “avalanche”", "ruggedness and high current load capacity before and/or during breakdown and secondly simple to produce with reproducible properties in view of technological latitudes of fluctuation of manufacturing processes.", "This object is accomplished according to the invention, in a semiconductor component of the kind initially mentioned, in that the regions of the first and second types of conductivity are so doped that charge carriers of the second conductivity type predominate in regions near the first surface and charge carriers of the first conductivity type in regions near the second surface.", "Preferably, the regions of the second conductivity type do not extend as far as up to the second zone, so that between said second surface and the second zone, a weakly doped region of the first conductivity type remains.", "It is possible, however, to allow the width of this region to go to “zero.”", "The weakly doped region, however, provides certain advantages, such as enhancement of the barrier voltage, “smooth”", "profile of the electrical field strength, or improvement of commutation properties of the inverse diode.", "In another refinement of the invention, it is provided that between the first and second surfaces, a degree of compensation effected by the doping is so varied that atomic residues of the second conductivity type dominate near the first surface and atomic residues of the first conductivity type near the second surface.", "In other words, there are sequences of p, p − , n − , n or n, n − , p − , p layers between the two surfaces.", "Advantageous improvements of the semiconductor device according to the invention (hereinafter also referred to as “compensation device”) are disclosed by the other dependent claims.", "The effect of the areas nested in each other, alternating different conductivity types, on the electrical field, is, in contrast to a conventional DMOS transistor, for example, as follows (“lateral”", "and “vertical”", "refer in the following to a vertical transistor): (a) There is a cross-field, “lateral”", "to the direction of the connection between the electrodes, the strength of which depends on the proportion of the lateral charge (line integral perpendicular to the lateral pn-junction) relative to the breakdown charge.", "This field leads to the separation of electrons and holes and to a reduction in the current-carrying cross-section along the current paths.", "This fact is of primary significance for the understanding of the processes in avalanche, of the breakdown characteristic curve, and of the saturation region of the output characteristics diagram.", "(b) The “vertical”", "electrical field parallel to the direction of the connection between the electrodes is determined locally by the difference between the adjacent dopings.", "This means that with an excess of donors (n-loaded distribution: the charge in the n-conductive areas exceeds the charge of the p-areas) on the one hand, a DMOS-like field distribution (maximum of the field on the blocking pn junction, decreasing field in the direction of the opposing back of the device) appears, whereby the gradient of the field is, however, clearly less than would correspond to the doping of the n-area alone.", "On the other hand, however, by overcompensation of the n-conductive area with acceptors, a field distribution rising in the direction of the back is possible (p-loaded distribution: excess of acceptors compared to the donors).", "In such a design, the field maximum lies at the bottom of the p-area.", "If the two dopings are exactly compensated, there is a horizontal field distribution.", "With an exact horizontal field distribution, the maximum of the breakdown voltage is obtained.", "If the acceptors or the donors predominate, the breakdown voltage drops in each case.", "If the breakdown voltage is then plotted as a function of the degree of compensation, a parabolic characteristic is obtained.", "Constant doping in the p- and n-conductive areas or even a locally varying doping with periodic maxima of equal height results in a comparatively sharply pronounced maximum of the “compensation parabola.”", "For the benefit of a “production window”", "(including the fluctuations of all relevant individual processes), a comparatively high breakdown voltage must be steered for in order to obtain reliable yields and production reliability.", "Consequently, the objective must be to make the compensation parabola as flat and as broad as possible.", "When the blocking voltage is applied to the device, the drift region, i.e., the region of the areas of opposite doping arranged in pairs, is cleared of mobile charge carriers.", "The positively charged donor cores and the negatively charged acceptor cores remain in the spreading space charge region.", "They then determine the course of the field.", "The flow of current through the space charge region causes a change in the electric field when the concentration of the charge carrier associated with the flow of current comes into the region of the background doping.", "Electrons compensate donors;", "holes compensate acceptors.", "For the stability of the device, it is also very important which doping predominates locally, where charge carriers are generated, and how their concentrations result along their current paths.", "For the following embodiments, for an understanding of the basic mechanism, initially a constant doping of the p- and n-conductive areas is assumed.", "In the on-state and especially in the saturation region of the output characteristics of a MOS transistor, a pure stream of electrons flows from the channel into an n-doped area, also referred to as a “column”", "in a vertical transistor, whereby in the base an increasing focusing of the flow of current occurs because of the electrical cross-field.", "High-current stability is promoted by dominance of the n-doping;", "however, since the channel region with its positive temperature coefficient eliminates inhomogeneous current distribution in a cell field, this mode of operation is rather uncritical.", "Reduction in the current density is obtained through partial shadowing of the channel connection (cf.", "DE 198 08 348 A1).", "With regard to the breakdown characteristic or its course, the following must be taken into consideration: The generation of electrons and holes occurs in the region of maximum field strength.", "The separation of the two types of charge carriers is performed by the electrical cross-field.", "Along the two current paths in the p- and n-area, respectively, focusing and further multiplication occurs.", "Ultimately, also no effect of a partial channel shadowing occurs.", "Stability is present only when the mobile charge carriers cause a rise in the electrical field outside their source and thus a rise in the breakdown voltage of the respective cell.", "For compensation devices this means stability in the p- and n-loaded region, but not in the maximum of the compensation parabola.", "In the p-loaded region, the breakdown occurs at the “bottom”", "of the column.", "The electrons flow out of the drift region and thus do not affect the field.", "The holes are pulled through the longitudinal electrical field to the top source contact.", "In the process, the hole current is focused along its path by the electrical cross-field: The current density rises here.", "Thus, the longitudinal electrical field is initially affected near the surface.", "As a result of compensation of the excess acceptor cores (p-loaded distribution), a reduction in the gradient of the electrical field and a rise in the breakdown voltage occur.", "This situation is stable as long as the field there remains clearly below the critical field strength (for silicon: approximately 270 kV/cm for a charge carrier concentration of approximately 10 15 cm −3 ).", "In the n-loaded region with an excess of donors, the breakdown is near the surface.", "The holes flow to the source contact and still affect the field on their path from their source to the p-well.", "The objective must consequently be to place the breakdown location as near as possible to the p-well.", "This can be accomplished, for example, by a local elevation in the n-doping.", "The electrons flow through the complete drift zone to the back and likewise affect the field along their current path.", "Stability is obtained when the effect of the electron current prevails over that of the hole current.", "Since the geometry of the cell arrangement plays an important role here, there is a region of stable and instable characteristic curves especially near the maximum of compensation parabola.", "The conditions in the avalanche are very similar to those of a breakdown.", "The currents are, however, clearly higher and have with a rated current as much as twice the rated current of the transistor.", "Since the electrical cross-field always causes a clear focusing of the current, in compensation devices the stability range is left at comparatively low current loads.", "Physically, this means that the current-induced rise in the field has already advanced so much that locally the breakdown field strength has been reached.", "The longitudinal electrical field can then not rise further locally;", "the curvature of the longitudinal electrical field, however, increases which results in a drop in the breakdown voltage of the cell in question.", "In the characteristic curve of an individual cell and also in the simulation, this is reflected by a negative differential resistance;", "i.e., the voltage drops as the current rises.", "In a large transistor with more than 10,000 cells this results in a very rapid inhomogencous redistribution of the current.", "A filament is formed, and the transistor melts locally.", "This yields the following consequences for the stability of compensation devices: (a) Due to the separation of electrons and holes there is no “auto-stabilization”", "as with IGBTs and diodes.", "Instead, the degree of compensation, field distribution, and breakdown location must be set exactly.", "(b) On the compensation parabola, with constant doping of the p- and n-areas or “columns”, there are stable regions in the clearly p- and in the clearly n-charged regions.", "The two regions are not contiguous.", "Thus, there is only an extremely small production window.", "With constant doping of the p- and n-areas or columns, the compensation parabola is extremely steep.", "The breakdown location moves within a few percent from the bottom of the p-column in the direction of the surface.", "(c) For each compensation device, there is a current destruction threshold in the avalanche which is directly coupled with the degree of compensation.", "The degree of compensation, on the other hand, determines the achievable breakdown voltage and effects the R DS (on) gain.", "(d) With constant doping of the p- and n-areas, the devices are—as mentioned above—instable near the maximum of the compensation parabola.", "This results in the fact that the devices with the highest blocking voltage are destroyed in the avalanche test.", "As explained above, to prevent the disadvantages, the degree of compensation is varied along the doping areas, i.e., in a vertical structure from the top in the direction of the back of the transistor, such that the atomic cores of the second conductivity type dominate near the surface and the atomic cores of the first conductivity type dominate near the back.", "The resultant field distribution has a “hump-shaped”", "curve with a maximum at approximately one-half of the depth(cf.", "FIG. 6 ).", "Thus, both the electrons and holes affect the field distribution in the breakdown and in the avalanche.", "Both types of charge carriers have a stabilizing effect, since in each case they run from their source into areas in which they compensate the dominating excess background doping.", "There is thus a continuous stability range from p-loaded to n-loaded degrees of compensation.", "A variation of the degree of compensation due to production fluctuations shifts the breakdown location only slightly in the vertical direction and continuously back and forth, as long as this variation is less than the technically adjusted variation of the degree of compensation.", "The size of this modification of the degree of compensation also determines the limits of the stability range.", "Thus, the production window becomes freely selectable.", "The focusing of the currents is clearly less pronounced since both types of charge carriers travel only one-half the path in the region of the compressing electrical cross-field.", "Thus, the devices can be stressed with clearly higher currents in the avalanche.", "Since in a variation of the degree of compensation, e.g., in the direction toward “n-loading”, the electrical field increases in each case in the upper area of the drift region, but simultaneously decreases in the lower area (vice versa with variations toward p-loaded distribution), the breakdown voltage varies only relatively little as a function of the degree of compensation.", "Thus, the compensation parabola becomes preferably flat and wide.", "The vertical variation of the degree of compensation can be effected by variation of the doping in the p-region or by variation of the doping in the n-region or by variation of the doping in both regions.", "The variation of the doping along the column may have a constant rise or be in a plurality of steps.", "In principle, the variation increases monotonically from a p-loaded degree of compensation to an n-loaded degree of compensation.", "The invention can be readily applied even with p-channel transistors.", "In that case, an appropriately altered course of the semiconductor regions occurs: A (p, p-dominated, n-dominated, n) course is replaced by an (n, n-dominated, p-dominated, p) course.", "The stability limits are reached on the n-loaded side when the field runs horizontally near the surface over an appreciable part of the drift region.", "On the p-loaded side the stability limits are reached when the field runs horizontally near the bottom of the compensating column region over a noticeable part of the drift region.", "In general, the compensation parabola becomes flatter and wider the greater the gradient of the degree of compensation.", "The breakdown voltage in the maximum of the compensation parabola drops accordingly.", "Another important limitation of the variation of the degree of compensation results from the requirement to remain below the breakdown charge.", "In addition, with greater elevation of the p-column doping near the surface, current pinch-off effects occur near the surface (lateral JFET effect).", "For 600 V devices, a variation of the degree of compensation lengthwise of the p- and n-areas of 50%, for example, is advantageous.", "Although above the starting point has been primarily a vertical transistor, the semiconductor device according to the invention can, in principle, have a vertical or even a lateral structure.", "With a lateral structure, n- and p-conductive plate-shaped areas are, for example, arranged laterally stacked in each other.", "Applications for such lateral transistors are, for example, found in the smart power sector or in microelectronics;", "vertical transistors are, in contrast, produced primarily in power electronics.", "The vertical modification of the degree of compensation is very simple to implement since in the individual epitaxial planes, only the implantation dose must be altered.", "The “real”", "compensation dose is then implanted in the middle epitaxial layer;", "below that, for example, 10% less in each case, above that, for example, 10% more in each case.", "However, instead of the implantation dose, it is possible to alter the epitaxial doping.", "By means of the more manageable variation, it is possible to reduce the production costs.", "The number of necessary epitaxial layers can be reduced, and the openings for the compensation implantation can be reduced as a result of greater variation of the implanted dose due to the greater relative variation of the resist dimension with simultaneously prolonged subsequent diffusion for the merging of the individual p-regions into the “column.”", "The structure according to the invention is produced by the following individual steps: First, a multi-μm-thick, n-doped epitaxial layer is applied to a semiconductor substrate.", "The p-doping ions are introduced into this epitaxial layer via a resist mask by means of ion implantation.", "Next, the entire process is repeated as often as necessary until there is an adequately thick n-multi epitaxial layer with embedded p-centers aligned with each other and stacked.", "The production of the actual device then occurs, by means of, for example, the processing of the base zones, the source zones, the front metalization, and the gate electrodes in a field effect transistor.", "By thermal diffusion, the p-doped centers merge into a rippled vertical column.", "Due to intrinsic compensation, the concentration of the p- or n-doping material is always substantially higher than the resultant electrically active doping.", "The ripple of the vertical column is expressed in a varying acceptor-donor ratio k c (z) per horizontal plane.", "The electrical compensation varies accordingly in each horizontal plane in the semiconductor body.", "The ripple of the column causes no significant change in the horizontal field.", "Consequently, in the first approximation, the contribution U Bh is considered unaffected by the ripple.", "In the vertical direction, layers with non-horizontally compensated p-and n-charges alternate.", "An epitaxial layer corresponds to a complete ripple period and, consequently, corresponds to two adjacent pn-junctions.", "Due to the production fluctuations in the epitaxy cycles, the charge balance is not equalized over the entire volume of a pn-junction such that the degree of compensation does not equal 0.", "In a semiconductor device according to the present invention, the voltage consumed in the blocked state in the cell field between anodes and cathodes or in a field effect transistor vertically between source and drain must also be discharged laterally on the edge of the semiconductor device.", "Semiconductor devices are often operated up to a breakdown.", "In this case, a very high current flows through the impact ionization which occurs.", "In order not to destroy the semiconductor device, no excessively high current densities may occur, i.e., the breakdown current must be distributed as uniformly as possible over the entire semiconductor device.", "However, this requirement can be fulfilled only if the cell field carries the majority of this current.", "If the semiconductor device breaks down in the edge structure at a smaller blocking voltage than the cell field, this results in most cases in irreversible thermal damage to the semiconductor device.", "The semiconductor device must, consequently, be avalanche-rugged.", "Avalanche-rugged semiconductor devices, especially vertical transistors, reduce the safety distance necessary to manage overvoltages, whereby in many applications comparatively low-blocking transistors may be used, which require at the same R DS (on) a comparatively small semiconductor device surface and are thus more economical.", "With conventional high-voltage MOSFETs, this is very significant since the R DS (on) of these transistors rises disproportionately with the breakdown voltage.", "With conventional power devices, expensive surface-mounted structures or structures near the surface usually result in the situation that the semiconductors device edge can block more voltage than the cell field.", "The lower-lying semiconductor device volume is homogeneously doped so low that it withstands the necessary voltage without structuring.", "With the semiconductor devices according to the present invention, which use the production process of intrinsic compensation, the demands with regard to the edge structure are intensified because here even the lower-lying volumes under the edge must be processed.", "The material actually accommodating the blocking voltage, i.e., the epitaxial layer above the highly doped semiconductor substrate, is relatively low ohmic and will only block a fraction of the required voltage.", "The blocking capability for the cell field is achieved only with the introduction of the counter doped columns.", "For the volume below the edge, there are, in principle, two different processing methods: 1.", "The semiconductor edge may be processed separately from the cell field, i.e., in additional steps.", "An overall counter doping of the substrate on the semiconductor edge, e.g., by means of overall edge implantation and diffusion, is conceivable.", "Thus, an overall intrinsically compensated and thus highly blocking edge can be produced.", "Such a procedure is, however, associated with very high costs.", "The column structure in the cell field is continued into the edge, whereby the substrate is also built up to basically the same blocking voltages as in the cell field.", "A minimal increase, for example, in the dielectric strength of the edge may be obtained in many cases by means of a suitable variation of the deep compensation profile of the columns, as this has been described on the preceding pages for the cell field, whereby, however, the tolerance range compared to the cell field and thus the tolerance range of the entire semiconductor device becomes smaller.", "Additionally, additional effects may provoke breakdown on the edge of the semiconductor device.", "On the one hand, the surface-mounted edge structures or structures near the surface cause additional field distortions and generate centers of high field strength.", "On the other hand, it may be necessary to apply an expedient negative “error charge”", "to the edge, which causes a curvature of the equipotential lines toward the semiconductor device surface, whereby these can be picked up and carried by the surface structure.", "This corresponds to a field discharge on the semiconductor device edge.", "This error charge condition may also cause a voltage-induced premature breakdown of the semiconductor device edge compared to the cell field.", "Accordingly, it is best to reduce the horizontal components of electric field and simultaneously the vertical ripple of the compensation profile on the edge.", "Both result in higher blocking voltages on the semiconductor device edge.", "To implement this, the local separation must be eliminated or at least weakened in the charge centers of opposing polarity, i.e., an intrinsic compensation must be undertaken.", "Thus, a high-voltage resistant edge structure is created, which consists of a plurality of floating zones of the second conductivity type, which are separated by intermediate zones of the first conductivity type, whereby the width of the intermediate zones and width of the floating zones are smaller than the width of the areas of the first and of the second conductivity type, which are nested in each other inside the cell fields.", "These floating zones and intermediate zones are doped such that the charge carriers of floating zones and of intermediate zones are completely cleared with the application of blocking voltage.", "Thus, preferably, the edge volume is processed in one and the same operation, whereby both the thickness of an individual epitaxial layer and the cell grid is reduced in size in the edge region, yielding at the end of the process homogeneous dopant distribution for both types of charge carriers for each edge cell.", "With regard to the ratio of unmasked surface per cell to the total cell surface in the edge region, the charge applied by implantation can be ideally adapted to the charge which is defined by the epitaxy.", "In order to achieve ideal blockability, a charge balance, i.e., intrinsically compensated condition, is sought.", "Preferably, the thickness of the individual epitaxial layers will be designed according to specifications which the cell field defines.", "This again yields a vertically rippled compensation profile on the semiconductor edge, but in a substantially weaker form than in the cell field.", "A reduction in the cell grid results in the fact that the resolution of the doping material source is reduced, whereby the boundaries of the individual diffusion fronts become blurred.", "An additional advantage of the edge design described is the coupling between the production defects in the edge and in the cell field since error mechanisms act in both regions in the same direction.", "BRIEF DESCRIPTION OF THE DRAWINGS The invention is explained in detail in the following with reference to the drawings.", "They depict: FIG. 1 a top view of an n-channel lateral MOS transistor according to a first exemplary embodiment of the invention, FIG. 2 a cross-section of an n-channel lateral MOS transistor with V-shaped grooves according to a second exemplary embodiment of the invention, FIGS. 3 a through 3 d various layouts in the semiconductor device according to the invention, FIG. 4 a cross-section through an n-channel lateral MOS transistor according to a third exemplary embodiment of the invention, FIG. 5 the course of the degree of compensation K along the line C-D in FIG. 4 , FIG. 6 the course of the electrical field along the line C-D in FIG. 4 , FIG. 7 the course of the breakdown voltage as a function of the degree of compensation for constant doping and for variable doping, FIG. 8 a concrete example of the cell design for an n-channel MOS transistor, FIGS. 9 a through 9 c various square edge structure layouts in the semiconductor device according to the invention, FIGS. 10 a through 10 c various strip edge structure layouts in the semiconductor device according to the invention, FIG. 11 a hexagonal edge structure layout in the semiconductor device according to the invention, FIG. 12 a cross-section through an n-channel MOS transistor according to a fourth exemplary embodiment with an edge structure layout, and FIG. 13 a cross-section through an n-channel MOS transistor according to a fifth exemplary embodiment with a different edge structure layout.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 depicts a top view of an n-channel MOS transistor with an n + -conductive drain zone 15 , an n + -conductive source zone 16 , a gate electrode 8 , and a p-conductive area 5 .", "This p-conductive area 5 extends finger-like into an n-conductive area 4 on a semiconductor substrate 1 , such that the areas 4 and 5 are “nested”", "in each other.", "The gate electrode 8 may, for example, be made of polycrystalline silicon, whereas an isolation layer not shown in FIG. 1 below this gate electrode 8 is made, for example, of silicon dioxide and/or silicon nitride.", "In the p-conductive area 5 , a p-charge excess is present in a zone I;", "a “neutral”", "charge, in a zone II;", "an n-charge excess, in a zone III.", "This means that in the area 5 in the zone I, the p-charge dominates the charge of the surrounding n-conductive area 5 ;", "that also in the zone II, the p-charge exactly compensates the charge of the surrounding n-conductive area 5 ;", "and that in the zone III, the p-charge is less than the charge of the surrounding n-conductive area 5 .", "It is thus significant that the charge of the p-area 5 is variable whereas the charge of the n-areas 4 is in each case constant.", "The p-conductive area 5 extends from the edge of the source zone 16 , i.e. from a surface A to a dashed line surface B in the n-conductive region 4 .", "This surface B is positioned at a distance from the drain zone 15 , such that there is, between the surface B and the drain zone 15 , an n-conductive region 13 in which there is no “nesting”", "with p-conductive regions 5 .", "However, it is also possible to shift the surface B to the edge of the drain zone 15 , such that there is no n-conductive region 13 .", "Advantageously, however, the surface B is positioned at a distance from the drain electrode 15 , which results in an increase of the blocking voltage, a smoother course of the electrical field, and an improvement of the commutating characteristics of the inverse diode.", "FIG. 2 depicts a cross-section through another exemplary embodiment of the semiconductor device according to the invention in the form of an n-channel MOS transistor with a drain electrode 2 and a gate insulation layer 9 between the gate electrode 8 and the channel region, which is provided under the insulation layer 9 between a source zone 16 and a drain zone 15 in a p-conductive region 5 .", "Also, in this exemplary embodiment, the p-conductive areas 5 in the zones I, II, and III have variable doping, as was explained above with reference to FIG. 1 .", "The exemplary embodiments of FIGS. 1 and 2 depict two preferred design possibilities for lateral structures of the semiconductor device according to the invention.", "Essential in the two structures is the fact that the reported variable doping is present in the areas 5 and that these areas 5 do not reach the drain zone 15 , i.e., terminate in a surface B at a distance from this drain zone 15 .", "However, it is possible to move the surface B toward the edge of the drain zone 15 .", "As stated above, the degree of compensation can be obtained by variation of the doping of the p-conductive areas 5 or of the n-conductive areas 4 .", "FIGS. 3 a through 3 d depict various layouts for the semiconductor device according to the invention with hexagonal polysilicon structures 17 and polysilicon openings 18 ( FIG. 3 a ), in which aluminum contact holes 19 ( FIG. 3 b ) may be provided.", "FIG. 3 c depicts a layout with rectangular polysilicon structures 20 and corresponding polysilicon openings 18 and aluminum contact holes 19 , whereas FIG. 3 d schematically depicts, in a top view and in cross-section, a strip structure with polysilicon gate electrodes 8 and aluminum electrodes 21 .", "FIGS. 3 a through 3 d depict how the semiconductor device according to the invention can be designed with different structures.", "FIG. 4 depicts a cross-section through an n-channel MOS transistor with an n + -conductive silicon semiconductor substrate 1 , a drain electrode 2 , a first n-conductive layer 13 , the second layer 3 with n-conductive areas 4 and p-conductive areas 5 , p-conductive zones 6 , n-conductive zones 7 , gate electrodes 8 made, for example, from polycrystalline silicon or metal, which are embedded in an isolating layer 9 made, for example, from silicon dioxide, and a source metalization 10 made, for example, from aluminum.", "Here again, the p-conductive areas 5 do not reach the n + -conductive semiconductor substrate.", "For the sake of clarity, FIG. 4 depicts only the metal layers hatched, although the remaining areas or zones are also depicted in cross-section.", "In the p-conductive areas 5 , there is a p-charge excess in a zone I, a “neutral”", "charge in the zone II, and an n-charge excess in zone III.", "This means that in the area 5 which forms a “p-column”", "in the zone I, the charge of the p-column dominates the charge of the surrounding n-conductive area 5 , further that in the zone II, the charge of the p-column precisely compensates the charge of the surrounding n-area 5 , and that in the zone III, the charge of the p-column does not yet dominate the charge of the surrounding n-area 5 .", "It is also essential that the charge of the p-areas 5 is variable, whereas the charge of the n-areas 4 is in each case constant.", "However, it is possible here, as in the preceding exemplary embodiments, that the charge of the p-conductive areas 5 is constant and the charge of the n-conductive areas is varied.", "It is likewise possible to design the charge variable in both areas 4 and 5 .", "FIG. 5 depicts in a cross-section C-D the course of the degree of compensation K over the depth t of the n-channel MOS transistor: As is discernible from FIG. 5 , the degree of compensation K rises monotonically with a constant gradient or in steps from the point C to point D. It is discernible from FIG. 6 that the electrical field E has a substantially constant curvature over the area 5 between the points C and D. FIG. 7 depicts compensation parabolas for a constant and a variable doping of the p-conductive areas 5 in the exemplary embodiment of FIG. 4 .", "The degree of compensation K is plotted in percentages on the abscissa, whereas the ordinate indicates the breakdown voltage U in volts.", "One curve 11 depicts the breakdown voltage U for a variable doping, whereas a curve 12 depicts the breakdown voltage for a constant doping.", "It is clear that the variable doping brings a considerable drop in the breakdown voltage from approximately 750 V to approximately 660 V. However, in exchange, a larger range of the degree of compensation can be used.", "FIG. 8 depicts finally a cell design in a cross-section with a drain D, a source S, and a gate G, the n + -conductive semiconductor substrate 1 , an n-conductive semiconductor region 13 , the n-conductive layer 3 , and n-conductive regions 4 as well as p-conductive regions 5 for the p-conductive region 5 under the source electrode S. In FIG. 8 the degrees of compensation, for example, between +30% and −20% are reported, whereby a degree of compensation “0”", "indicates true compensation between n-doping and p-doping.", "Here, the doping thus varies within the “p-column”", "by a factor 3 whereas the doping in the “n-columns”", "is constant.", "FIGS. 9 a through 9 c depict, in principle, as in FIGS. 3 a through 3 d , how the semiconductor device according to the invention can be designed with different structures which extend into the edge region.", "As can be discerned in FIGS. 9 a through c , FIGS. 10 a through c and in FIG. 11 , in the semiconductor edge region, a large number of floating zones 5 ′, are formed from the second conductivity type and are separated from intermediate zones 4 ′ of the first conductivity type.", "The width of the intermediate zones 4 ′ and the widths of the floating zones 5 ′ are smaller than the widths of the regions 4 , 5 inside the cell field.", "The floating zones 5 ′ and the intermediate zones 4 ′ are dimensioned such that their charge carriers are completely cleared with the application of blocking voltage.", "The zones 5 ′, which are designed lightly p-doped in the present exemplary embodiment, are “floating”, i.e., they have an undefined potential.", "The floating zones 5 ′ are positioned at a distance from each other, whereby the region between the floating zones 5 ′ defines an intermediate zone 4 ′.", "This intermediate zone 4 ′ typically has the same doping concentration as the doping in the zones 4 within the cell field.", "FIGS. 9 a, b, and c depict different variations of the widths of the floating zones compared to the basic widths in the cell field.", "FIGS. 10 a, b, and c depict the same thing with the strip edge structure layout and FIG. 11 with a hexagonal edge structure layout.", "FIG. 12 and FIG. 13 depict the n-channel MOS transistor known from FIG. 4 , which has been expanded by an intrinsically compensated edge termination.", "The transistor is built in known fashion with an n + -conductive silicon semiconductor substrate 1 , a drain electrode 2 , a first n-conducting layer 13 , a second layer with n-conducting areas 4 and p-conductive areas 5 , p-conductive zones 6 , n-conductive zones 7 , gate electrodes 8 made, for example, from polycrystalline silicon or metal, which are embedded in an insulation layer 9 made, for example, from silicon dioxide, and a source metalization 10 made, for example, of aluminum.", "In the present figures in each case two p-conductive areas 5 and n-conductive areas 4 are depicted on the left side.", "Toward the right, additional p-conductive areas 5 ′ and n-conductive areas 4 ′ extend alternatingly.", "The p-conductive areas 5 ′ have, compared to the p-conductive areas 5 , roughly half the width;", "however, they extend roughly as far into the n-conductive region 13 in the direction of the substrate 1 .", "The regions 5 ′, 4 ′ lying adjacent the regions 4 , 5 are connected to a p-conductive zone 6 ′, which connects via a contact hole with the source metalization 10 .", "The p-conductive zone 6 ′ forms a p-ring known from the prior art.", "The p-conductive zones 6 ′ has, in contrast to the cell field, no n-conductive zone, to prevent parasitic transistors.", "The n- and p-conductive areas 4 ′, 5 ′ extend far beyond the p-conductive zone 6 ′ in the direction of the edge of the device.", "On the outermost edge, there is a so-called channel stopper configuration, which consists of a gate electrode 8 ′, which is electrically connected with an n-conductive zone 7 ″, which for its part is accommodated in a p-conductive zone 6 ″ in the n-conductive region 13 .", "The so-called space charge region stopper depicted in FIG. 13 constitutes an alternative to the channel stopper configuration depicted in FIG. 12 .", "This space charge region stopper consists only of a well conductive n + -conductive zone, which is placed in the n-conductive region.", "Common to both exemplary embodiments is the fact that the contact holes of the p-conductive zone 6 ′ are substantially larger compared to the contact holes in the n- or p-conductive zones 7 , 6 .", "The result of this is that the gate electrode 8 ′, which lies above the areas 4 ′, 5 ′ is designed substantially smaller compared to the gate electrodes 8 of the cell field.", "The grid, in which the areas 4 ′, 5 ′ are arranged, is roughly half as large as the areas 4 , 5 of the cell field." ]
TECHNICAL FIELD [0001] The present invention relates generally to climate control duct systems for vehicles. More particularly, the present invention relates to a climate control duct architecture which includes partitions which provide distribution of air as it exits the HVAC. By strategic positioning and configuring of the partitions the duct architecture may be tuned to provide maximum console airflow and desired distribution across the system with a minimum amount of interference to the airflow due to turbulence. BACKGROUND OF THE INVENTION [0002] Modern vehicle interiors are provided with climate control systems. Central to the climate control system is the HVAC which produces climatized air for distribution into the interior of the vehicle through a variety of ducts. Known arrangements of ducts in climate control systems include a path to the panel registers and to the console which takes place at a distance away from the air outlet of the HVAC. Essentially such systems build a plenum structure into the ducts where the flow can become disorganized. To provide a proper amount of airflow known systems frequently must rely on on-board auxiliary devices to increase airflow. [0003] Furthermore, the duct architecture is constrained by packaging requirements. In the modern vehicle a greater number of components required for safety and comfort of the occupants are being included in and adjacent to the instrument panel while at the same time designs of the instrument panel itself put increased pressure on the designer to engineer appropriate duct work. Accordingly, the package needed for ducts often gets compromised. This, together with the new designs of instrument panels which often have more lay back angles, brings about continuous challenges to climate control designers to engineer systems that deliver acceptable levels of vehicle airflow. [0004] As a consequence, console airflow of known systems often ends up being low and the comfort levels of the rear passengers are often not attained. [0005] Accordingly, as in so many areas of vehicle design, an improved method of providing a more efficient arrangement for providing adequate airflow to all vehicle passengers is desired. SUMMARY OF THE INVENTION [0006] The present invention represents advancement in the art of vehicle climate control system duct architecture. The arrangement disclosed herein includes a partitioned duct having an inlet that is fitted to the outlet of the HVAC. The partitioned duct includes two or more air outlets and a like number of air channels formed between the inlet and the air outlets. A dividing wall is formed to separate each of the channels. The dividing wall includes a leading edge which is provided adjacent the outlet of the HVAC. A number of dividing walls may be used based on the number of airflow channels. For example, if there are two airflow channels there will be a dividing wall separating one channel from the other. If there are four airflow channels, then there would be a dividing wall which separates each channel from the adjacent channel. [0007] The partitioned duct may include a base element, a cover element, and an intermediate element situated between the base element and the cover element. The base, cover and intermediate elements may be formed from a molded material. [0008] The arrangement and configuration of the airflow chambers and the dividing wall or walls of the partitioned duct may be adjusted or tuned for maximum airflow and minimum turbulence. The arrangement and configuration of the airflow chambers and the dividing wall or walls could be adapted as required for the number and placement of downstream ducts and vent outlets. [0009] By providing for the distribution of air at the exit of the HVAC the arrangement disclosed herein reduces air turbulence thus increasing airflow through the duct system. This streamlined arrangement virtually eliminates disorganized airflow and the consequential deceleration and acceleration by splitting airflow directed to each outlet at the earliest stage of the airflow path. The arrangement of the present invention provides for optimum airflow with minimum energy requirements. [0010] Other advantages and features of the invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS [0011] For a more complete understanding of this invention, reference should now be made to the embodiment illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention wherein: [0012] FIG. 1 illustrates a perspective view of an airflow distribution duct of the known art; [0013] FIG. 2 illustrates a diagrammatic sectional view of the airflow distribution duct of FIG. 1 taken along lines 2 - 2 which illustrates the airflow through the plenum according to known designs in which the airflow is slowed and turbulence is created as illustrated by the airflow lines; [0014] FIG. 3 illustrates a perspective view of a partitioned duct according to the disclosed invention; [0015] FIG. 4 illustrates an exploded view of the elements of the partitioned duct of FIG. 3 ; [0016] FIG. 5 illustrates a perspective view of a duct system which incorporates the partitioned duct of the disclosed invention; [0017] FIG. 6 illustrates a view of the partitioned duct of the disclosed invention taken from its air inlet end; [0018] FIG. 7 illustrates a view similar to that of FIG. 6 illustrating the pathways of the individual airflow channels; [0019] FIG. 8 illustrates an alternate perspective view of the partitioned duct of the disclosed invention; and [0020] FIG. 9 illustrates a diagrammatic sectional view of the partitioned duct of the disclosed invention which illustrates the airflow through the duct where the airflow is unimpeded and is virtually void of evidence of turbulence. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0021] In the following figures, the same reference numerals are used to refer to the same components. In the following description, various operating parameters and components are described for one constructed embodiment. These specific parameters and components are included as examples and are not meant to be limiting. [0022] With reference to FIG. 1 , a perspective view of an airflow distribution duct according to the known art, generally illustrated as 10 . The airflow distribution duct 10 includes a body 12 , a first outlet 14 , a second outlet 16 , a third outlet 18 , a fourth outlet 20 , a fifth outlet 22 , and a sixth outlet 24 . There can be a greater or lesser number of outlets as is known in the art and the arrangement shown is only for illustrative purposes as representing the state of the prior art. Of particular interest is the body 12 which conventionally includes a plenum section for receiving inflowing air coming from the HVAC to which individual outlets 14 , 16 , 18 , 20 , 22 and 24 are connected. Conventionally illustrated in FIG. 1 is the body 12 having two plenum volumes, including a first plenum volume 28 and a second plenum volume 30 . [0023] The arrangement of the known art as defined by the plural plenums results in an inefficient way of delivering air to and through the duct system of the vehicle. This is illustrated in FIG. 2 in which a diagrammatic sectional view of the airflow distribution duct 12 of FIG. 1 is illustrated. Typically the airflow distribution duct 12 includes a plenum 32 having an airflow inlet 34 . The airflow inlet 34 is fixed to the outlet end of an HVAC (not shown). The airflow distribution duct 12 typically includes one or two restricted areas 36 which are utilized to restrict air to various outlets to balance the system. [0024] As illustrated in FIG. 2 , the reliance of the prior art upon the plenum arrangement results in impeded and turbulent airflow through the airflow distribution duct 12 . At the upper end of the airflow distribution duct 12 is an area of relatively low velocity 38 in which a great deal of poorly flowing, turbulent air is shown. Another area of low velocity is in an area of restricted flow 40 which is adjacent the restricted area 36 . A third area of low velocity 42 arises where the airflow distribution duct 12 meets a floor outlet 44 . The area of low velocity 42 is an area of stagnant air. [0025] The airflow problems shown in FIG. 2 are intended to be illustrative and not limiting but suggest typical airflow problems created in known duct systems which rely upon a plurality of plenums to distribute air to the various airflow outlets. Impeded airflow of the type illustrated results in low velocity of airflow particularly at the most remote outlets of the vehicle climate control system, such as would be found in the rear seat area of a van or of an SUV. Vehicle designers have overcome this problem in part by providing on-board auxiliary airflow devices (not shown) to increase airflow. [0026] The disclosed invention overcomes the limitations of the prior art by providing a tunable partitioned duct, generally illustrated as 50 , shown in FIG. 3 . The tunable partitioned duct 50 includes a body 52 having a first outlet 54 , a second outlet 56 , a third outlet 58 , a fourth outlet 60 , a fifth outlet 62 , and a sixth outlet 64 . A greater or lesser number of outlets may be provided. The tunable partitioned duct 50 embodies improvements over the prior art which are substantially internal and thus the tunable partitioned duct 50 of the disclosed invention can replace existing airflow distribution ducts of the type shown in FIGS. 1 and 2 and described in relation thereto. Thus capable of being a substituting unit, the remainder of the duct system of the vehicle can be used with the disclosed invention without modification, adding to convenience of design and cost savings. [0027] An exploded view of the tunable partitioned duct 50 of the disclosed invention is shown in FIG. 4 . As shown, the tunable partitioned duct 50 preferably but not absolutely is composed of an inlet half 66 , a cover half 68 , and an intermediate portion 70 . One or more of the inlet half 66 , the cover half 68 , and the intermediate portion 70 may be formed by molding, although it is to be understood that a variety of alternate methods of construction may be utilized. [0028] As illustrated in FIG. 4 , a variety of dividing walls are provided to define channels into which flowing air is selectively directed. Centrally provided on the inlet half 66 is a central divider 72 . Similarly a central divider 74 is provided on the intermediate portion 70 while a central divider 76 is provided on the cover half 68 . When the inlet half 66 , the intermediate portion 70 and the cover half 68 are assembled the central divider 72 , the central divider 74 , and the central divider 76 operate as one as a central divider 77 illustrated in FIGS. 6 and 7 . [0029] Additional walls are formed in the tunable partitioned duct 50 for directing airflow. Specifically, a right-left divider 78 is formed on the inlet half 66 while a right-left divider 80 is formed on the intermediate portion 70 . A right-left divider 82 is formed on the cover half 68 . When the inlet half 66 , the intermediate portion 70 and the cover half 68 are assembled the right-left divider 78 , the right-left divider 80 , and the right-left divider 82 operate as one to divide the airflow between the first outlet 54 and the second outlet 56 . [0030] In addition to the right-left divider, the tunable partitioned duct 50 of the disclosed invention is fitted with a left-right divider for directing airflow. Specifically, a left-right divider 84 is formed on the inlet half 66 while a left-right divider 86 is formed on the intermediate portion 70 . A left divider 88 is formed on the cover half 68 . When the inlet half 66 , the intermediate portion 70 and the cover half 68 are assembled the left-right divider 84 , the left-right divider 86 , and the left-right divider 88 operate as one to divide the airflow between the fourth outlet 60 and the sixth outlet 64 . [0031] A divider 90 is also provided in the intermediate portion 70 to divide the inflowing air between that air flowing to a first series of air outlets (the first outlet 54 , the second outlet 56 , the fourth outlet 60 , and the sixth outlet 64 ) and a second series of air outlets (the third outlet 58 and the fifth outlet 62 ). The divider 90 is also illustrated in FIGS. 6 and 7 . [0032] An exemplary duct system arrangement for a vehicle is shown in FIG. 5 and is generally illustrated as 100 . The duct system arrangement 100 includes the tunable partitioned duct 50 two outflow ducts 102 and 104 , a distribution duct 106 , a rear lead duct 108 , and a vent 110 . As noted above, the tunable partitioned duct 50 may be utilized with known and existing systems, such as that illustrated in FIG. 5 , with no modifications. It is to be understood that the duct system arrangement 100 of FIG. 5 is shown for illustrative purposes only and a wide array of versions and configurations may be adapted as well. [0033] FIGS. 6 and 7 illustrate a view of the tunable partitioned duct 50 of the present invention viewed from its inlet side. As illustrated, the inlet side is divided into a number of channels by the central divider 77 and the divider 90 . The channels include a first airflow channel 120 , a second airflow channel 122 , a third airflow channel 124 , and a fourth airflow channel 126 . The first airflow channel 120 is fluidly continuous with the fourth airflow outlet 60 , the second airflow channel 120 is fluidly continuous with the second airflow outlet 56 , the third airflow channel 124 is fluidly continuous with the fifth airflow outlet 62 , and the fourth airflow channel 126 is fluidly continuous with the third airflow outlet 58 . [0034] In addition to the first airflow channel 120 , the second airflow channel 122 , the third airflow channel 124 , and the fourth airflow channel 126 , a fifth airflow channel 128 is provided in fluid communication with the sixth airflow outlet 64 and a sixth airflow channel 130 is provided in fluid communication with the first airflow outlet 54 . Furthermore, and optionally as shown in FIG. 6 , a seventh airflow channel 132 and an eighth airflow channel 134 are provided. The seventh airflow channel 132 and the eighth airflow channel 134 may be fluidly associated with, for example, lap coolers (not shown). It is to be understood that a greater or lesser number of airflow channels may be provided. However, regardless of the number of channels, the dividers which define the channels are substantially adjacent with and may abut directly against the outlet of the HVAC. [0035] With respect to FIG. 8 , a perspective view of the tunable partitioned duct 50 as disclosed in the present invention is illustrated. The angle of this view differs from the perspective angle shown and described in FIG. 3 . This view more clearly shows the sixth airflow outlet 64 . In addition, this view illustrates extension ducts 140 and 142 fitted to the third airflow outlet 58 and the fifth airflow outlet 62 respectively. Again, this arrangement can be readily modified as required for adaptation to a particular vehicle arrangement. [0036] The tunable partitioned duct illustrated herein and described above is effective at reducing turbulence and increasing airflow as illustrated in FIG. 9 , which is a diagrammatic sectional view of the partitioned duct of the disclosed invention. The airflow through the duct is illustrated. As may be understood by the figure, the airflow is virtually entirely unimpeded and is virtually void of evidence of turbulence. The continuous and clear airflow illustrated by the various and several lines denote high velocity without areas of stagnation or restriction, offering a considerable advantage over the prior art illustrated in FIGS. 1 and 2 . [0037] The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims. Specifically, and as noted above, the variety, position and number of lighting elements provided in conjunction with the floor console can be readily altered to meet the requirements of a specific application without deviating from the present invention.
A climate control duct architecture having partitions to provide effective distribution of air immediately as it exits the HVAC. By strategic positioning and configuring of the partitions the duct architecture may be tuned to provide maximum console airflow and desired system airflow distribution with a minimum amount of interference to the airflow due to turbulence.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "TECHNICAL FIELD [0001] The present invention relates generally to climate control duct systems for vehicles.", "More particularly, the present invention relates to a climate control duct architecture which includes partitions which provide distribution of air as it exits the HVAC.", "By strategic positioning and configuring of the partitions the duct architecture may be tuned to provide maximum console airflow and desired distribution across the system with a minimum amount of interference to the airflow due to turbulence.", "BACKGROUND OF THE INVENTION [0002] Modern vehicle interiors are provided with climate control systems.", "Central to the climate control system is the HVAC which produces climatized air for distribution into the interior of the vehicle through a variety of ducts.", "Known arrangements of ducts in climate control systems include a path to the panel registers and to the console which takes place at a distance away from the air outlet of the HVAC.", "Essentially such systems build a plenum structure into the ducts where the flow can become disorganized.", "To provide a proper amount of airflow known systems frequently must rely on on-board auxiliary devices to increase airflow.", "[0003] Furthermore, the duct architecture is constrained by packaging requirements.", "In the modern vehicle a greater number of components required for safety and comfort of the occupants are being included in and adjacent to the instrument panel while at the same time designs of the instrument panel itself put increased pressure on the designer to engineer appropriate duct work.", "Accordingly, the package needed for ducts often gets compromised.", "This, together with the new designs of instrument panels which often have more lay back angles, brings about continuous challenges to climate control designers to engineer systems that deliver acceptable levels of vehicle airflow.", "[0004] As a consequence, console airflow of known systems often ends up being low and the comfort levels of the rear passengers are often not attained.", "[0005] Accordingly, as in so many areas of vehicle design, an improved method of providing a more efficient arrangement for providing adequate airflow to all vehicle passengers is desired.", "SUMMARY OF THE INVENTION [0006] The present invention represents advancement in the art of vehicle climate control system duct architecture.", "The arrangement disclosed herein includes a partitioned duct having an inlet that is fitted to the outlet of the HVAC.", "The partitioned duct includes two or more air outlets and a like number of air channels formed between the inlet and the air outlets.", "A dividing wall is formed to separate each of the channels.", "The dividing wall includes a leading edge which is provided adjacent the outlet of the HVAC.", "A number of dividing walls may be used based on the number of airflow channels.", "For example, if there are two airflow channels there will be a dividing wall separating one channel from the other.", "If there are four airflow channels, then there would be a dividing wall which separates each channel from the adjacent channel.", "[0007] The partitioned duct may include a base element, a cover element, and an intermediate element situated between the base element and the cover element.", "The base, cover and intermediate elements may be formed from a molded material.", "[0008] The arrangement and configuration of the airflow chambers and the dividing wall or walls of the partitioned duct may be adjusted or tuned for maximum airflow and minimum turbulence.", "The arrangement and configuration of the airflow chambers and the dividing wall or walls could be adapted as required for the number and placement of downstream ducts and vent outlets.", "[0009] By providing for the distribution of air at the exit of the HVAC the arrangement disclosed herein reduces air turbulence thus increasing airflow through the duct system.", "This streamlined arrangement virtually eliminates disorganized airflow and the consequential deceleration and acceleration by splitting airflow directed to each outlet at the earliest stage of the airflow path.", "The arrangement of the present invention provides for optimum airflow with minimum energy requirements.", "[0010] Other advantages and features of the invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and the appended claims.", "BRIEF DESCRIPTION OF THE DRAWINGS [0011] For a more complete understanding of this invention, reference should now be made to the embodiment illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention wherein: [0012] FIG. 1 illustrates a perspective view of an airflow distribution duct of the known art;", "[0013] FIG. 2 illustrates a diagrammatic sectional view of the airflow distribution duct of FIG. 1 taken along lines 2 - 2 which illustrates the airflow through the plenum according to known designs in which the airflow is slowed and turbulence is created as illustrated by the airflow lines;", "[0014] FIG. 3 illustrates a perspective view of a partitioned duct according to the disclosed invention;", "[0015] FIG. 4 illustrates an exploded view of the elements of the partitioned duct of FIG. 3 ;", "[0016] FIG. 5 illustrates a perspective view of a duct system which incorporates the partitioned duct of the disclosed invention;", "[0017] FIG. 6 illustrates a view of the partitioned duct of the disclosed invention taken from its air inlet end;", "[0018] FIG. 7 illustrates a view similar to that of FIG. 6 illustrating the pathways of the individual airflow channels;", "[0019] FIG. 8 illustrates an alternate perspective view of the partitioned duct of the disclosed invention;", "and [0020] FIG. 9 illustrates a diagrammatic sectional view of the partitioned duct of the disclosed invention which illustrates the airflow through the duct where the airflow is unimpeded and is virtually void of evidence of turbulence.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0021] In the following figures, the same reference numerals are used to refer to the same components.", "In the following description, various operating parameters and components are described for one constructed embodiment.", "These specific parameters and components are included as examples and are not meant to be limiting.", "[0022] With reference to FIG. 1 , a perspective view of an airflow distribution duct according to the known art, generally illustrated as 10 .", "The airflow distribution duct 10 includes a body 12 , a first outlet 14 , a second outlet 16 , a third outlet 18 , a fourth outlet 20 , a fifth outlet 22 , and a sixth outlet 24 .", "There can be a greater or lesser number of outlets as is known in the art and the arrangement shown is only for illustrative purposes as representing the state of the prior art.", "Of particular interest is the body 12 which conventionally includes a plenum section for receiving inflowing air coming from the HVAC to which individual outlets 14 , 16 , 18 , 20 , 22 and 24 are connected.", "Conventionally illustrated in FIG. 1 is the body 12 having two plenum volumes, including a first plenum volume 28 and a second plenum volume 30 .", "[0023] The arrangement of the known art as defined by the plural plenums results in an inefficient way of delivering air to and through the duct system of the vehicle.", "This is illustrated in FIG. 2 in which a diagrammatic sectional view of the airflow distribution duct 12 of FIG. 1 is illustrated.", "Typically the airflow distribution duct 12 includes a plenum 32 having an airflow inlet 34 .", "The airflow inlet 34 is fixed to the outlet end of an HVAC (not shown).", "The airflow distribution duct 12 typically includes one or two restricted areas 36 which are utilized to restrict air to various outlets to balance the system.", "[0024] As illustrated in FIG. 2 , the reliance of the prior art upon the plenum arrangement results in impeded and turbulent airflow through the airflow distribution duct 12 .", "At the upper end of the airflow distribution duct 12 is an area of relatively low velocity 38 in which a great deal of poorly flowing, turbulent air is shown.", "Another area of low velocity is in an area of restricted flow 40 which is adjacent the restricted area 36 .", "A third area of low velocity 42 arises where the airflow distribution duct 12 meets a floor outlet 44 .", "The area of low velocity 42 is an area of stagnant air.", "[0025] The airflow problems shown in FIG. 2 are intended to be illustrative and not limiting but suggest typical airflow problems created in known duct systems which rely upon a plurality of plenums to distribute air to the various airflow outlets.", "Impeded airflow of the type illustrated results in low velocity of airflow particularly at the most remote outlets of the vehicle climate control system, such as would be found in the rear seat area of a van or of an SUV.", "Vehicle designers have overcome this problem in part by providing on-board auxiliary airflow devices (not shown) to increase airflow.", "[0026] The disclosed invention overcomes the limitations of the prior art by providing a tunable partitioned duct, generally illustrated as 50 , shown in FIG. 3 .", "The tunable partitioned duct 50 includes a body 52 having a first outlet 54 , a second outlet 56 , a third outlet 58 , a fourth outlet 60 , a fifth outlet 62 , and a sixth outlet 64 .", "A greater or lesser number of outlets may be provided.", "The tunable partitioned duct 50 embodies improvements over the prior art which are substantially internal and thus the tunable partitioned duct 50 of the disclosed invention can replace existing airflow distribution ducts of the type shown in FIGS. 1 and 2 and described in relation thereto.", "Thus capable of being a substituting unit, the remainder of the duct system of the vehicle can be used with the disclosed invention without modification, adding to convenience of design and cost savings.", "[0027] An exploded view of the tunable partitioned duct 50 of the disclosed invention is shown in FIG. 4 .", "As shown, the tunable partitioned duct 50 preferably but not absolutely is composed of an inlet half 66 , a cover half 68 , and an intermediate portion 70 .", "One or more of the inlet half 66 , the cover half 68 , and the intermediate portion 70 may be formed by molding, although it is to be understood that a variety of alternate methods of construction may be utilized.", "[0028] As illustrated in FIG. 4 , a variety of dividing walls are provided to define channels into which flowing air is selectively directed.", "Centrally provided on the inlet half 66 is a central divider 72 .", "Similarly a central divider 74 is provided on the intermediate portion 70 while a central divider 76 is provided on the cover half 68 .", "When the inlet half 66 , the intermediate portion 70 and the cover half 68 are assembled the central divider 72 , the central divider 74 , and the central divider 76 operate as one as a central divider 77 illustrated in FIGS. 6 and 7 .", "[0029] Additional walls are formed in the tunable partitioned duct 50 for directing airflow.", "Specifically, a right-left divider 78 is formed on the inlet half 66 while a right-left divider 80 is formed on the intermediate portion 70 .", "A right-left divider 82 is formed on the cover half 68 .", "When the inlet half 66 , the intermediate portion 70 and the cover half 68 are assembled the right-left divider 78 , the right-left divider 80 , and the right-left divider 82 operate as one to divide the airflow between the first outlet 54 and the second outlet 56 .", "[0030] In addition to the right-left divider, the tunable partitioned duct 50 of the disclosed invention is fitted with a left-right divider for directing airflow.", "Specifically, a left-right divider 84 is formed on the inlet half 66 while a left-right divider 86 is formed on the intermediate portion 70 .", "A left divider 88 is formed on the cover half 68 .", "When the inlet half 66 , the intermediate portion 70 and the cover half 68 are assembled the left-right divider 84 , the left-right divider 86 , and the left-right divider 88 operate as one to divide the airflow between the fourth outlet 60 and the sixth outlet 64 .", "[0031] A divider 90 is also provided in the intermediate portion 70 to divide the inflowing air between that air flowing to a first series of air outlets (the first outlet 54 , the second outlet 56 , the fourth outlet 60 , and the sixth outlet 64 ) and a second series of air outlets (the third outlet 58 and the fifth outlet 62 ).", "The divider 90 is also illustrated in FIGS. 6 and 7 .", "[0032] An exemplary duct system arrangement for a vehicle is shown in FIG. 5 and is generally illustrated as 100 .", "The duct system arrangement 100 includes the tunable partitioned duct 50 two outflow ducts 102 and 104 , a distribution duct 106 , a rear lead duct 108 , and a vent 110 .", "As noted above, the tunable partitioned duct 50 may be utilized with known and existing systems, such as that illustrated in FIG. 5 , with no modifications.", "It is to be understood that the duct system arrangement 100 of FIG. 5 is shown for illustrative purposes only and a wide array of versions and configurations may be adapted as well.", "[0033] FIGS. 6 and 7 illustrate a view of the tunable partitioned duct 50 of the present invention viewed from its inlet side.", "As illustrated, the inlet side is divided into a number of channels by the central divider 77 and the divider 90 .", "The channels include a first airflow channel 120 , a second airflow channel 122 , a third airflow channel 124 , and a fourth airflow channel 126 .", "The first airflow channel 120 is fluidly continuous with the fourth airflow outlet 60 , the second airflow channel 120 is fluidly continuous with the second airflow outlet 56 , the third airflow channel 124 is fluidly continuous with the fifth airflow outlet 62 , and the fourth airflow channel 126 is fluidly continuous with the third airflow outlet 58 .", "[0034] In addition to the first airflow channel 120 , the second airflow channel 122 , the third airflow channel 124 , and the fourth airflow channel 126 , a fifth airflow channel 128 is provided in fluid communication with the sixth airflow outlet 64 and a sixth airflow channel 130 is provided in fluid communication with the first airflow outlet 54 .", "Furthermore, and optionally as shown in FIG. 6 , a seventh airflow channel 132 and an eighth airflow channel 134 are provided.", "The seventh airflow channel 132 and the eighth airflow channel 134 may be fluidly associated with, for example, lap coolers (not shown).", "It is to be understood that a greater or lesser number of airflow channels may be provided.", "However, regardless of the number of channels, the dividers which define the channels are substantially adjacent with and may abut directly against the outlet of the HVAC.", "[0035] With respect to FIG. 8 , a perspective view of the tunable partitioned duct 50 as disclosed in the present invention is illustrated.", "The angle of this view differs from the perspective angle shown and described in FIG. 3 .", "This view more clearly shows the sixth airflow outlet 64 .", "In addition, this view illustrates extension ducts 140 and 142 fitted to the third airflow outlet 58 and the fifth airflow outlet 62 respectively.", "Again, this arrangement can be readily modified as required for adaptation to a particular vehicle arrangement.", "[0036] The tunable partitioned duct illustrated herein and described above is effective at reducing turbulence and increasing airflow as illustrated in FIG. 9 , which is a diagrammatic sectional view of the partitioned duct of the disclosed invention.", "The airflow through the duct is illustrated.", "As may be understood by the figure, the airflow is virtually entirely unimpeded and is virtually void of evidence of turbulence.", "The continuous and clear airflow illustrated by the various and several lines denote high velocity without areas of stagnation or restriction, offering a considerable advantage over the prior art illustrated in FIGS. 1 and 2 .", "[0037] The foregoing discussion discloses and describes an exemplary embodiment of the present invention.", "One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims.", "Specifically, and as noted above, the variety, position and number of lighting elements provided in conjunction with the floor console can be readily altered to meet the requirements of a specific application without deviating from the present invention." ]
RELATED APPLICATION INFORMATION This application is a 371 of International Application PCT/JP2010/003236 filed 13 May 2010 entitled “Printing Blanket, Printer And Method For Producing Printing Blanket”, which was published on 9 Sep. 2011, with International Publication Number WO 2011/108034 A1, and which claims priority from Japanese Patent Applications No. 2010-49269 filed on 5 Mar. 2010 and 2010-97747 filed on 21 Apr. 2010, the content of which is incorporated herein by reference. TECHNICAL FIELD The present invention generally relates to printing blankets, printing devices, and methods of manufacturing printing blankets, and particularly relates to a printing blanket suitable for pad printing that involves picking up ink and transferring the picked-up ink to a to-be-printed surface, a printing device having the printing blanket, and a method of manufacturing the printing blanket. BACKGROUND ART Pad printing is a conventional process in which a printing blanket (i.e., a printing pad) is pressed against a printing original plate (i.e., an image plate), on which ink is disposed in accordance with a printing pattern, so as to transfer (pick up) the ink from the printing original plate, and then the printing blanket is pressed against a to-be-printed surface so as to transfer (deliver) the ink to a to-be-printed surface, whereby the printing pattern is printed onto the to-be-printed surface. There is disclosed an invention in which, in order to prevent reduction in the printing quality, a printing original plate is reciprocally moved so as to shake and stir ink in an ink box that is in contact with the printing original plate and thereby make the ink less likely to be cured (see Patent Literature 1, for example). CITATION LIST Patent Literature Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2008-114496 (Pages 9-10, FIG. 1) SUMMARY OF INVENTION Technical Problem According to the invention disclosed in Patent Literature 1, a printing blanket is an elastic body made of silicone rubber or the like containing silicone oil so as to impart elasticity (flexibility), and is formed in a substantially hemispherical shape (bullet shape) or a substantially semi-cylindrical shape (bullet-shaped cross section). Further, in order to make the printing blanket fit to the to-be-printed surface, the printing blanket needs to be soft (i.e., have a low elastic modulus and be easily elastically deformed). However, when the printing blanket is pressed onto the printing original plate and is deformed, silicone oil in the printing blanket may come out to the surface thereof, or the printing blanket may become locally worn or damaged, which results in the following problems. (a) It becomes difficult to transfer (deliver) the ink from the printing original plate to the printing blanket, which results in a blurred or unclear printing pattern being printed on the to-be-printed surface. (b) Further, ink and silicone oil accumulate on the printing original plate, and the resulting excessive amount of ink and oil contaminate the printing original plate. The contaminants are transferred to the printing blanket, which results in a smeared printing pattern being printed on the to-be-printed surface. (c) Furthermore, in the case of removing ink not having been picked up and remaining on the printing original plate, frequent cleaning may cause damage to the printing original plate and roughen the surface thereof, which may reduce the service life of the printing original plate. This leads to frequent replacement with a new printing original plate, resulting in increased printing costs (equipment costs). (d) In the case of applying a coating to the to-be-printed surface with the printing pattern printed thereon, the coating is repelled by the silicone oil component, and therefore a desired coating cannot be formed. (e) On the other hand, in the case where the hardness of the printing blanket is increased, it becomes difficult to print the printing pattern across a wide area on a curved surface. Then, the printable area is reduced, which may result in reduced design properties of the printing pattern. In the case of printing the printing pattern across a wide area, it is necessary to perform small area printing a plurality of times, which increases the print costs. (f) Further, since the ink is transferred to the to-be-printed surface by pressing the printing blanket against the flat printing original plate and the curved to-be-printed surface, the distal end (the lowermost point or the lowermost line) of the printing blanket and the portion in the vicinity thereof become particularly degraded or damaged, or the printing blanket may become damaged by a protruding portion of the to-be-printed surface. Such local degradation or damage makes the printing blanket unusable, and thus the entire printing blanket is discarded. The present invention has been made to overcome the above problems. A first object of the present invention is to provide a printing blanket that excellently fits to a curved to-be-printed surface while preventing silicone oil contained in the printing blanket from coming out to the surface of the printing blanket when the printing blanket is deformed. A second object of the present invention is to provide a printing device having the printing blanket. A third object of the present invention is to provide a method of manufacturing a printing blanket that, even if the printing blanket is locally degraded or damaged, does not need to be discarded entirely and can perform high-quality printing. Solution to Problem (1) According to the present invention, there is provided: a printing blanket that is configured to pick up ink, which has been applied to a printing original plate in accordance with a printing pattern, from the printing original plate by being pressed against the printing original plate and then deliver the picked-up ink to a to-be-printed surface by being pressed against the to-be-printed surface, and thereby print the printing pattern on the to-be-printed surface, the printing blanket including a double-layer structure having: a flexible elastic body containing silicone oil; and a lesser-flexible coating layer containing silicone oil and covering a part of a surface of the elastic body. (2) With regard to (1) described above, the elastic body has a cylindrical shape, and the coating layer covers an outer circumferential surface of the main body. (3) With regard to (1) described above, the elastic body has a substantially semi-cylindrical shape, a substantially conical shape, or a substantially pyramidal shape, and the coating layer covers a predetermined area of the elastic body containing an apex thereof. (4) With regard to (3) described above, the thickness of the coating layer is greater at the apex of the elastic body and in the vicinity of the apex than at a position away from the apex. (5) Further, according to the present invention, there is provided: a printing device including: the printing blanket of any one of (1) through (4); a pad mounting unit on which the printing blanket is disposed; a moving unit configured to movably support the pad mounting unit; a controller configured to control movement of the moving unit; and a main body in which the moving unit and the controller are disposed. (6) Further, according to the present invention, there is provided: a method of manufacturing a printing blanket including an elastic body having a substantially semi-cylindrical shape and a sheet bonded to a side surface of the elastic body having a substantially arcuate cross section, the method including the steps of: molding an elastic body having a substantially semi-cylindrical shape; forming a sheet having a predetermined size; placing the sheet on a flat surface; pressing a side surface of the elastic body against the placed sheet; and applying an adhesive to one or both of the side surface of the elastic body and a surface of the sheet against which the elastic body is to be pressed, prior to the pressing step; wherein the sheet is bonded to the side surface of the elastic body in the pressing step. (7) With regard to (6) described above, the method further includes the step of applying a mold release agent to any one of the side surface of the elastic body, the surface of the sheet against which the elastic body is to be pressed, and the adhesive. (8) With regard to (6) or (7) described above, the sheet and the elastic body contain silicone oil, and the sheet is less flexible than the elastic body. Advantageous Effects of Invention (i) A printing blanket according to the present invention includes a double-layer structure having a flexible elastic body and a lesser-flexible coating layer covering a part of the surface of the elastic body, and therefore excellently fits to a curved to-be-printed surface. Thus, when the printing blanket is deformed, silicone oil contained in the elastic body is substantially blocked by the lesser-flexible coating layer covering the surface of the elastic body, which makes the silicone oil less likely to come out to the surface of the coating layer. Accordingly, it is possible to solve the problems (a) through (d) described above. The number of coating layers is not limited to one. That is, in the case where two, three, or more coating layers are provided, the printing blanket has a three-layer structure, a four-layer structure, or a multi-layer structure having more than four layers. It should be noted that, in this specification, an elastic body is not limited to those in which the relationship between a load applied thereto and the amount of deformation due to the applied load is liner, but may include those in which that relationship is non-linear and which returns to the original shape immediately after or with a delay of a predetermined time period from when a load having been applied thereto is removed. Further, “flexible” and “soft” refer to a property of being easily deformed by application of a relatively lower load. For example, in the case of the materials that linearly deform elastically, “flexible” and “soft” are equivalent to having a low elastic modulus. On the other hand, “lesser-flexible” and “hard” refer to a property of requiring a “relatively higher load” to be applied for deformation compared to that required by a substance that is “flexible” or “soft”. (ii) Further, since the thickness of the coating layer is greater at the apex of the elastic body, which is more likely to be worn (degraded or damaged) due to a higher load applied thereto, than in the other area, it is possible to prevent the service life from being reduced due to local wear. (iii) A printing device according to the present invention has a printing blanket that solves the problems (a) through (e) described above, and therefore can print a clean printing pattern at low cost. (iv) According to a method of manufacturing a printing blanket of the present invention, the side surface of an elastic body is pressed against a sheet disposed on a flat surface, and thus a printing blanket including an elastic body having a side surface with the sheet bonded thereto is manufactured. That is, the lowermost portion of the side surface of the elastic body comes into contact (line contact) with the sheet. Then, as the elastic body is pressed further, the contact area gradually expands from that position. Therefore, air is prevented from being trapped on the contact surface (i.e., the bonding surface). Accordingly, it is possible to pick up ink, which has been applied to a printing original plate in accordance with a printing pattern, from the printing original plate accurately (i.e., while preventing a part of the ink from not being picked up (from remaining thereon)), and transfer the ink to a to-be-printed surface accurately. The sheet can be manufactured at low cost, and it is easy to remove a degraded or damaged sheet from the elastic body and bond a new sheet thereto. This allows the elastic body to be used repeatedly and thereby achieves low printing costs. (v) Further, a mold release agent may be applied to any one of the side surface of the elastic body, the surface of the sheet against which the elastic body is pressed, and the adhesive so as to facilitate replacement of sheets. It should be noted that the elastic body is made of the same material as related-art printing blankets. Further, although the material of the sheet is not particularly limited, the sheet is capable of picking up ink, which has been applied to a printing original plate (not shown) in accordance with a printing pattern, from the printing original plate when being pressed against the printing original plate, and is capable of delivering the picked-up ink to a to-be-printed surface when being pressed against the to-be-printed surface. Accordingly, the sheet has the substantially same function as the elastic body. (vi) Moreover, the sheet has elasticity (flexibility) so as to excellently fit to a curved to-be-printed surface. Thus, when the elastic body is deformed, silicone oil contained in the elastic body is substantially blocked by the lesser-flexible sheet covering the surface of the elastic body, which makes the silicone oil less likely to come out to the surface of the coating layer. Accordingly, it is possible to solve the problems (a) through (e) described above. (vii) The sheet may be less flexible than the sheet in order to make the substantial blocking effect by the sheet more pronounced. The present invention, however, is not limited thereto. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a perspective view illustrating a printing blanket according to Example 1 in Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view illustrating a printing blanket according to Example 2 in Embodiment 1 of the present invention. FIG. 3 is a cross-sectional view illustrating a printing blanket according to Example 3 in Embodiment 1 of the present invention. FIG. 4 is a schematic front view illustrating a printing device according to Embodiment 2 of the present invention. FIG. 5 illustrates a method of manufacturing a printing blanket according to Embodiment 3 of the present invention, wherein (a) of FIG. 1 is a perspective view of an elastic body, and (b) is a perspective of a sheet. FIG. 6 shows front views for illustrating respective steps of the method of manufacturing a printing blanket according to Embodiment 3 of the present invention. FIG. 7 is a front view for illustrating another example of the method of manufacturing a printing blanket according to Embodiment 3 of the present invention. FIG. 8 shows front views for illustrating respective steps of the method of manufacturing a printing blanket according to Embodiment 4 of the present invention. DESCRIPTION OF EMBODIMENTS Embodiment 1: Printing Blanket FIGS. 1 through 3 illustrate a printing blanket according to Embodiment 1 of the present invention. More specifically, FIG. 1 is a schematic perspective view of Example 1; FIG. 2 is a schematic cross-sectional view of Example 2; and FIG. 3 is a schematic cross-sectional view of Example 3. EXAMPLE 1 Referring to FIG. 1 , a printing blanket 1 according to Example 1 has a double-layer structure formed of an elastic body la having a cylindrical shape, and a coating layer 1 d covering an outer circumferential surface 1 b of the elastic body 1 a. The elastic body 1 a and the coating layer 1 d contain silicone oil in order to ensure transfer (pick-up and deliver) of ink and to impart elasticity (flexibility) thereto. The coating layer 1 d is harder (contains a smaller amount of silicone oil) than the elastic body 1 a. Accordingly, the elastic body 1 a is easily deformed, and the coating layer 1 d is deformed in accordance with deformation of the elastic body 1 a . Therefore, the printing blanket 1 excellently fits to the curved to-be-printed surface. Further, when the printing blanket 1 is deformed, the silicone oil contained in the elastic body 1 a is substantially blocked by the coating layer 1 d surrounding the elastic body 1 a . Also, the content of the silicone oil in the coating layer 1 d is small. Therefore, the silicone oil is less likely to come out to a surface 1 e of the coating layer 1 d. It should be noted that, in the present invention, the number of coating layers 1 d is not limited to one, and additional one, two, or more coating layers may be provided on top of the coating layer 1 d . In this case, the printing blanket 1 has a three-layer structure, a four-layer structure, or a multi-layer structure having more than four layers. The coating layer 1 d is bonded to the elastic body 1 a . Therefore, in the case where the coating layer 1 d is worn (degraded or damaged), the entire or a part of the worn coating layer 1 d may be removed such that a new coating layer may be formed thereon by using a coating process or the like. In this case, the printing blanket 1 has a double-layer structure formed of the original elastic body 1 a and a new coating layer, or has a three-layer structure formed of the original elastic body 1 a , a part of the worn original coating layer 1 d , and a new coating layer. It should be noted that, although the entire (360 degrees) outer circumferential surface of the elastic body 1 a is covered by the coating layer 1 d in the above description, the present invention is not limited thereto. For example, half the outer circumferential surface (180 degrees) or a third of the outer circumferential surface (120 degrees) of the elastic body 1 a may be covered by the coating layer 1 d . Further, in place of a cylindrical shape, the elastic body 1 a may have a semi-cylindrical shape such that a part or a front portion of the arcuate surface thereof may be covered by a coating layer. Since the printing blanket 1 is formed such that the silicone oil is less likely to come out to the surface 1 e , the following advantageous effects are obtained. (A) Ink applied to a printing original plate (not shown) is reliably transferred to the printing blanket 1 . This allows a printing pattern (not shown) to be clearly printed on a to-be-printed surface. (B) Ink is prevented from accumulating on the printing original plate (not shown), whereby the printing original plate is prevented from being contaminated. This allows a printing pattern to be printed clean without any smear (not shown). (C) Further, there is no need to frequently clean the printing original plate (not shown), which prevents the surface thereof being roughened and thus extends the service life thereof. This reduces the frequency of replacing with a new printing original plate, resulting in reduced printing costs (equipment costs). (D) In the case where the coating layer is worn (degraded or damaged), the printing blanket can be used continuously only by replacing the entire or a part of the coating layer 1 d without replacing elastic bodies, which results in low material costs. (E) Further, it is possible to print a printing pattern across a wide area on a curved surface using a single printing blanket 1 . This simplifies the printing process and thereby reduces the printing costs. This also makes it possible to impart design properties to the printing pattern and thereby enhances the commercial value of the print object. (F) Furthermore, even in the case of applying a surface treatment such as coating onto the to-be-printed surface, since there is little silicone oil adhering the to-be-printed surface, the coating is prevented from being repelled by the silicone oil, which allows a high-quality to-be-printed surface (coating surface) to be obtained. EXAMPLE 2 Referring to FIG. 2 , a printing blanket 2 according to Example 2 has a double-layer structure formed of an elastic body 2 a having a substantially quadrangular pyramidal shape, and a coating layer 2 d covering a predetermined area of side faces 2 b of the elastic body 2 a , which predetermined area contains an apex 2 c of the elastic body 2 a. The elastic body 2 a has a substantially arcuate triangular cross section with the side faces 2 b projecting outward. The adjacent side faces 2 b are smoothly connected to each other, and the apex 2 c where the four side faces 2 b meet has a substantially partial spherical shape. The elastic body 2 a and the coating layer 2 d contain silicone oil in order to ensure transfer (pick-up and deliver) of ink. The coating layer 2 d is harder than the elastic body 2 a. Accordingly, the elastic body 2 a is easily deformed, and the coating layer 2 d is deformed in accordance with deformation of the elastic body 2 a . Therefore, as in the case of the printing blanket 1 of Example 1, the printing blanket 2 excellently fits to the curved to-be-printed surface, and the silicone oil is less likely to come out to a surface 2 e of the coating layer 2 d. It should be noted that, although a part of the side faces 2 b containing the apex 2 c of the elastic body 2 a is covered by the coating layer 2 d in the above description, the present invention is not limited thereto. The entire side faces 2 b may be covered by the coating layer 2 d . Further, in place of a substantially quadrangular pyramidal shape, the elastic body 2 a may have a shape similar to a three-sided pyramid, or a five or more-sided pyramid. The elastic body 2 a may have a conical shape with a rounded apex. EXAMPLE 3 Referring to FIG. 3 , a printing blanket 3 according to Example 3 has a double-layer structure formed of an elastic body 3 a having a hemispherical shape, and a coating layer 3 d covering a predetermined area of an outer surface 3 b of the elastic body 3 a , which predetermined area contains an apex (i.e., a south pole in FIG. 3 ) 3 c of the elastic body 3 a. The elastic body 3 a and the coating layer 3 d contain silicone oil in order to ensure transfer (pick-up and deliver) of ink. The coating layer 3 d is harder than the elastic body 3 a . Further, since the apex 3 c and a portion in the vicinity of the apex 3 c are more likely to be worn (degraded or damaged) due to high pressure applied thereto, the thickness of the coating layer 3 d is greater in this area than in the area away from the apex 3 c. Therefore, as in the case of the printing blanket 1 of Example 1, the printing blanket 3 excellently fits to the curved to-be-printed surface, and the silicone oil is less likely to come out to a surface 3 e of the coating layer 3 d . Further, although the apex 3 c and a portion in the vicinity of the apex 3 c are more likely to be worn due to high pressure that is applied thereto due to a pressing motion upon picking up the ink and upon delivering the ink to the to-be-printed surface, since the thickness of the coating layer 3 d is greater in the vicinity of the apex 3 c , the service life of the printing blanket 3 is extended. Further, only by forming a new coating layer for only a worn portion or only a predetermined area containing the worn portion, the original printing blanket 3 and the remaining portion of the original coating layer 3 d can be used continuously. Therefore, with inexpensive repairs, the printing blanket 3 can be used for a long period of time. Furthermore, as in the case of the printing blanket 1 , a wide area of the coating layer 3 d may be replaced. This results in low component costs. It should be noted that the shape of the elastic body 3 a is not limited and may have a shape similar to a cone or pyramid, or a semi-cylindrical shape. Further, the size of the area covered with the coating layer 3 d is not limited as long as the area contains the apex 3 c. Embodiment 2: Printing Device FIG. 4 is a schematic front view illustrating a printing device according to Embodiment 2 of the present invention. Referring to (a) of FIG. 4 , a printing device 10 includes a main body 11 , a moving unit 12 , a pad mounting unit 13 , a controller 14 , and the printing blanket 2 (see Example 2). The main body 11 includes a main body base 11 a , a main body stand 11 b fixed to the main body base 11 a , and a main body rail 11 c fixed to the upper end of the main body stand 11 b. The moving unit 12 includes an X-direction moving beam 12 x movably supported by (disposed on or suspended on) the main body rail 11 c , a Y-direction moving beam 12 y movably supported by (disposed on or suspended on) the X-direction moving beam 12 y , and a lifting unit 12 z that is disposed on the Y-direction moving beam 12 y and is configured to lift and lower the pad mounting unit 13 . The pad mounting unit 13 includes a mounting bar 13 a configured to be lifted or lowered by the lifting unit 12 z , and a mounting plate 13 b fixed to the lower end of the mounting bar 13 a . The printing blanket 2 is mounted on the lower surface of the mounting plate 13 b. The controller 14 moves the moving unit 12 so as to perform printing in accordance with an entered predetermined printing procedure. That is, the printing blanket 2 is moved to a position facing a printing original plate (i.e., an image plate) 4 on which ink is disposed in accordance with a printing pattern, and is lowered to be pressed against the printing original plate 4 , so that the ink is transferred to (picked up by) the printing blanket 2 . Then, the printing blanket 2 is lifted, is moved to a position facing a print object 5 , and is lowered so as to transfer (deliver) the ink to a to-be-printed surface. Thus, a printing pattern is printed on the surface of the print object 5 . Thus, since the printing device 10 includes the printing blanket 2 (Example 2), it is possible to print a clear and clean printing pattern on the to-be-printed surface at low costs. It is also possible to enhance the commercial value of the print object by printing a printing pattern with design properties imparted thereto. It should be noted that the printing blanket 1 or the printing blanket 3 may be used in place of the printing blanket 2 . Further, the moving unit 12 illustrated in the above description is formed of members that move in three directions, respectively. However, the present invention is not limited there to, and the moving unit 12 may include a robot whose distal end is movable in three directions. Referring to (b) of FIG. 4 , a printing device 20 includes a main body 21 , a moving unit 22 , a pad supporting unit 23 , a controller 24 , and the printing blanket 1 (see Example 1). The main body 21 includes a main body base 21 a , a main body stand 21 b fixed to the main body base 21 a , and a main body rail 21 c fixed to the upper end of the main body stand 21 b. The moving unit 22 is movably supported by (suspended on) the main body rail 11 c , and is configured to move itself in accordance with a control signal from the controller 24 . The pad supporting unit 23 has an end mounted on the moving unit 22 and the other end rotatably supporting the center of the printing blanket 1 . The controller 24 moves the moving portion 22 so as to perform printing in accordance with an entered predetermined printing procedure. That is, when the moving unit 22 moves rightward, the printing blanket 1 rotates while being pressed against a printing original plate (i.e., an image plate) 4 on which ink is disposed in accordance with a printing pattern, so that the ink is transferred to (picked up by) the printing blanket 1 . Then, when the moving unit 22 moves leftward, the printing blanket 1 rotates while being pressed against a print object 5 so as to transfer (deliver) the ink to a to-be-printed surface. Thus, a printing pattern is printed on the surface of the print object 5 . In order to prevent the surface le of the printing blanket 1 from sliding with respect to the surface of the printing original plate 4 and to prevent the surface le of the printing blanket 1 from sliding with respect to the surface of the print object 5 , the moving speed of the moving unit 22 is equal to the peripheral speed of the surface 1 e. Thus, since the printing device 20 includes the printing blanket 1 (Example 1), it is possible to print a clear and clean printing pattern on the to-be-printed surface at low costs. It is also possible to enhance the commercial value of the print object by printing a printing pattern with design properties imparted thereto. Embodiment 3: Method of Manufacturing Printing Blanket FIGS. 5 through 7 illustrate a method of manufacturing a printing blanket according to Embodiment 3 of the present invention. More specifically, (a) of FIG. 5 is a schematic perspective view of a part (an elastic body); (b) of FIG. 5 is a schematic perspective view of a part (a sheet); FIG. 6 shows front views for illustrating respective steps; and FIG. 7 is a schematic front view of another example. It should be noted that the same components are denoted by the same reference signs throughout the drawings, and a description thereof will be partially omitted. Further, the drawings are schematically illustrated, and the present invention is not limited to the shapes shown in the drawings (in particular, the thickness of the sheet is illustrated with exaggeration). Referring to FIGS. 5 through 7 , a printing blanket 30 has a substantially semi-cylindrical shape, and has a double-layer structure formed of an elastic body 31 and a sheet 32 bonded to the side surface of the elastic body 31 . The elastic body 31 includes a side face 31 a defining a convex surface, another side face 31 b that is plane-symmetric to the side face 31 a , a ridge line 31 c (technically, this portion has a certain width, but is referred to as a “line” for explanation purposes) smoothly connecting between the side surface 31 a and the side surface 31 b , and a mounting surface 1 d serving as a mounting surface to be attached to a printing apparatus (not shown). It should be noted that the ridge line 31 c defines the lowermost end of the elastic body 31 . Further, the cross sections of the side faces 31 a and 31 b do not have a perfect semicircular shape, but have a bullet shape (see (a) of FIG. 5 and (c) of FIG. 6 ). The sheet 32 has a rectangular shape with a predetermined thickness (e.g., 1 mm), and is capable of picking up ink, which has been applied to a printing original plate (not shown) in accordance with a printing pattern, from the printing original plate when being pressed against the printing original plate, and is capable of delivering the picked-up ink to a to-be-printed surface (not shown) when being pressed against the to-be-printed surface. The material (substance) thereof is not particularly limited. The elastic body 31 is also capable of picking up ink, which has been applied to a printing original plate (not shown) in accordance with a printing pattern, from the printing original plate through the sheet 32 when being pressed against the printing original plate, and is capable of delivering the picked-up ink to a to-be-printed surface (not shown) through the sheet 32 when being pressed against the to-be-printed surface. The material (substance) thereof is not particularly limited. Next, a description will be given of a manufacturing method with reference to FIG. 6 . An elastic body 31 having a substantially semi-cylindrical shape (a bullet-shaped cross section) is molded. Also, a sheet having a predetermined size (thickness, vertical length, and horizontal length) is formed. The sheet may be obtained by molding a sheet into a predetermined size, or by cutting a large sheet into a rectangle of a predetermined size. Subsequently, the sheet 32 is placed on a flat surface 33 (see (b) of FIG. 5 ). Then, an adhesive (not shown) is applied to the side faces 31 a and 1 b and the ridge line 31 c , and the elastic body 31 is lowered in the normal direction of the flat surface 33 so as to be pressed against the sheet 32 (see (a) and (b) of FIG. 6 ). Thus, the ridge line 31 c of the elastic body 31 first comes into contact (line contact) with the sheet 32 . Then, as the elastic body 31 is pressed further, the elastic body 31 (and the sheet 32 which deforms in accordance with deformation of the elastic body 31 ) is deformed. Thus the contact location gradually moves in the direction away from the ridge line 31 c such that the contact area expands (the contact surface expands so as to cover a greater area of the side faces 31 a and 1 b ). This prevents air from being trapped on the contact surface (i.e., the bonding surface). Then, when the entire surface of the sheet 32 comes into contact with (is bonded to) the elastic body 31 , lowering of the elastic body 31 is stopped. Then, immediately after stopping lowering of the elastic body 31 , or after maintaining the elastic body 31 in a pressed state for a predetermined time period after stopping lowering of the elastic body 31 , the elastic body 31 is lifted. Thus, the elastic body 31 returns to the original shape. In this way, a printing blanket 30 formed of the elastic body 31 with the sheet 32 bonded thereto (see (c) of FIG. 6 ) is obtained. Since the printing blanket 30 does not have any bubble (that is small enough to be invisible to the naked eye) trapped on the bonding surface of the sheet 32 , it is possible to prevent a part of the to-be-printed surface from not being printed (prevent blank portions from remaining on the to-be-printed surface) and therefore to perform high-quality printing. Moreover, the sheet 32 can be manufactured at low cost, and it is easy to bond the sheet 32 to the elastic body 31 . Therefore, even if the surface of the sheet 32 is locally degraded or damaged due to use, the degraded sheet 32 can be removed and replaced with a new sheet 32 at low cost. This allows high-quality printing to be performed continuously at low cost. On the other hand, in the case of forming, in place of the sheet 32 , a coating body having an inner surface that has a shape matching the shapes of the side faces 31 a and 1 b of the elastic body 31 and having a predetermined thickness by molding using a die, it is necessary to form a die for each shape of the elastic body 31 , resulting in an increase in the manufacturing cost of the printing blanket. Further, when bonding the coating body to the elastic body 31 , air is trapped between the inner surface of the coating body and the side faces 31 a and 1 b of the elastic body 31 , and therefore high-quality printing cannot be performed. It should be noted that, although an adhesive is applied to the elastic body 31 before the pressing step, the present invention is not limited thereto. An adhesive may be applied to the sheet 32 in place of the elastic body 31 , or to both the sheet 32 and the elastic body 31 . Further, the method of applying an adhesive is not particularly limited. An adhesive may be applied using a brush, or may be applied by spraying using a spray. Further, the sheet 32 may be placed on a concave surface 34 having an arcuate cross section (see FIG. 7 ) in place of the flat surface 33 . In this case, as in the case where the elastic body 31 is pressed against the flat surface 33 , since the contact area gradually expands in a predetermined direction, air is prevented from being trapped on the contact surface (i.e., the bonding surface), which allows high-quality printing to be performed. Embodiment 4: Method of Manufacturing Printing Blanket FIG. 8 shows front views for illustrating respective steps of the method of manufacturing a printing blanket according to Embodiment 4 of the present invention. It should be noted that the same components as those in Embodiment 3 are denoted by the same reference signs, and a description thereof will be partially omitted. Referring (a) of FIG. 8 , a sheet 35 has a thickness that gradually increases toward the center thereof in a width direction thereof. Further, the sheet 35 is disposed on a recessed surface 36 of a work table 37 . The recessed surface 36 is smoothly recessed toward the center thereof in a width direction thereof. In this case, since the depth of the recess of the recessed surface 36 varies in accordance with the varying thickness of the sheet 35 in the width direction, the upper surface of the sheet 35 placed on the recessed surface 36 is flat. Accordingly, when the elastic body 31 is pressed against the sheet 35 having a flat upper surface, air is prevented from being trapped on the contact surface (i.e., the bonding surface), which allows high-quality printing to be performed. Referring to (b) of FIG. 8 , as in the case of Embodiment 3, a printing blanket 40 is formed by pressing the elastic body 31 against the sheet 35 . Since the sheet 35 bonded to the printing blanket 40 has a thickness that gradually increases toward the ridge line 31 c gradually, that is, since the sheet 35 has a greater thickness in an area that is more likely to be severely worn, the printing blanket 40 can be used for a longer period of time. INDUSTRIAL APPLICABILITY According to the present invention, a printing blanket excellently fits to a curved to-be-printed surface while preventing silicone oil contained in the printing blanket from coming out to the surface of the printing blanket when the printing blanket is deformed. Accordingly, the present invention is widely used as printing blankets of various shapes and sizes, and printing devices having the printing blankets. Further, a sheet is bonded to an elastic body while preventing air from being trapped therebetween, which allows high-quality printing to be performed. Therefore, it is possible to manufacture a printing blanket at low cost. Accordingly, the present invention can be widely used a printing blanket manufacturing method for manufacturing printing blankets of various shapes and sizes. REFERENCE SIGNS LIST 1 printing blanket (Example 1) 1 a elastic body 1 b outer circumferential surface 1 d coating layer 1 e surface 2 printing blanket (Example 2) 2 a elastic body 2 b side face 2 c apex 2 d coating layer 2 e surface 3 printing blanket (Example 3) 3 a elastic body 3 b outer surface 3 c apex 3 d coating layer 3 e surface 4 printing original plate 5 print object 10 printing device (Embodiment 2) 11 main body 11 a main body base 11 b main body stand 11 c main body rail 12 moving unit 12 x X-direction moving beam 12 y Y-direction moving beam 12 z lifting unit 13 pad mounting unit 13 a mounting bar 13 b mounting plate 14 controller 20 printing device (Embodiment 2) 21 main body 21 a main body base 21 b main body stand 21 c main body rail 22 moving unit 23 pad supporting unit 24 controller 31 elastic body 31 a side face 31 b side face 31 c ridge line 31 d mounting surface 32 sheet 33 flat surface 34 concave surface 35 sheet 36 recessed surface 37 work table 30 printing blanket (Embodiment 3) 40 printing blanket (Embodiment 4)
A printing pad ( 2 ) having a double structure comprising a roughly quadrangular pyramid-shaped elastic body ( 2 a ) and a coating layer ( 2 d ) which covers a definite range of a side face ( 2 b ) including an apex ( 2 c ) of the elastic body ( 2 a ), wherein said elastic body ( 2 a ) and the coating layer ( 2 d ) contain a silicone oil to ensure ink transfer (receiving and delivering) and impart elasticity (flexibility), and the coating layer ( 2 d ) is made harder (i.e., containing the silicone oil in a smaller amount) than the elastic body ( 2 a ).
Condense the core contents of the given document.
[ "RELATED APPLICATION INFORMATION This application is a 371 of International Application PCT/JP2010/003236 filed 13 May 2010 entitled “Printing Blanket, Printer And Method For Producing Printing Blanket”, which was published on 9 Sep. 2011, with International Publication Number WO 2011/108034 A1, and which claims priority from Japanese Patent Applications No. 2010-49269 filed on 5 Mar. 2010 and 2010-97747 filed on 21 Apr. 2010, the content of which is incorporated herein by reference.", "TECHNICAL FIELD The present invention generally relates to printing blankets, printing devices, and methods of manufacturing printing blankets, and particularly relates to a printing blanket suitable for pad printing that involves picking up ink and transferring the picked-up ink to a to-be-printed surface, a printing device having the printing blanket, and a method of manufacturing the printing blanket.", "BACKGROUND ART Pad printing is a conventional process in which a printing blanket (i.e., a printing pad) is pressed against a printing original plate (i.e., an image plate), on which ink is disposed in accordance with a printing pattern, so as to transfer (pick up) the ink from the printing original plate, and then the printing blanket is pressed against a to-be-printed surface so as to transfer (deliver) the ink to a to-be-printed surface, whereby the printing pattern is printed onto the to-be-printed surface.", "There is disclosed an invention in which, in order to prevent reduction in the printing quality, a printing original plate is reciprocally moved so as to shake and stir ink in an ink box that is in contact with the printing original plate and thereby make the ink less likely to be cured (see Patent Literature 1, for example).", "CITATION LIST Patent Literature Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2008-114496 (Pages 9-10, FIG. 1) SUMMARY OF INVENTION Technical Problem According to the invention disclosed in Patent Literature 1, a printing blanket is an elastic body made of silicone rubber or the like containing silicone oil so as to impart elasticity (flexibility), and is formed in a substantially hemispherical shape (bullet shape) or a substantially semi-cylindrical shape (bullet-shaped cross section).", "Further, in order to make the printing blanket fit to the to-be-printed surface, the printing blanket needs to be soft (i.e., have a low elastic modulus and be easily elastically deformed).", "However, when the printing blanket is pressed onto the printing original plate and is deformed, silicone oil in the printing blanket may come out to the surface thereof, or the printing blanket may become locally worn or damaged, which results in the following problems.", "(a) It becomes difficult to transfer (deliver) the ink from the printing original plate to the printing blanket, which results in a blurred or unclear printing pattern being printed on the to-be-printed surface.", "(b) Further, ink and silicone oil accumulate on the printing original plate, and the resulting excessive amount of ink and oil contaminate the printing original plate.", "The contaminants are transferred to the printing blanket, which results in a smeared printing pattern being printed on the to-be-printed surface.", "(c) Furthermore, in the case of removing ink not having been picked up and remaining on the printing original plate, frequent cleaning may cause damage to the printing original plate and roughen the surface thereof, which may reduce the service life of the printing original plate.", "This leads to frequent replacement with a new printing original plate, resulting in increased printing costs (equipment costs).", "(d) In the case of applying a coating to the to-be-printed surface with the printing pattern printed thereon, the coating is repelled by the silicone oil component, and therefore a desired coating cannot be formed.", "(e) On the other hand, in the case where the hardness of the printing blanket is increased, it becomes difficult to print the printing pattern across a wide area on a curved surface.", "Then, the printable area is reduced, which may result in reduced design properties of the printing pattern.", "In the case of printing the printing pattern across a wide area, it is necessary to perform small area printing a plurality of times, which increases the print costs.", "(f) Further, since the ink is transferred to the to-be-printed surface by pressing the printing blanket against the flat printing original plate and the curved to-be-printed surface, the distal end (the lowermost point or the lowermost line) of the printing blanket and the portion in the vicinity thereof become particularly degraded or damaged, or the printing blanket may become damaged by a protruding portion of the to-be-printed surface.", "Such local degradation or damage makes the printing blanket unusable, and thus the entire printing blanket is discarded.", "The present invention has been made to overcome the above problems.", "A first object of the present invention is to provide a printing blanket that excellently fits to a curved to-be-printed surface while preventing silicone oil contained in the printing blanket from coming out to the surface of the printing blanket when the printing blanket is deformed.", "A second object of the present invention is to provide a printing device having the printing blanket.", "A third object of the present invention is to provide a method of manufacturing a printing blanket that, even if the printing blanket is locally degraded or damaged, does not need to be discarded entirely and can perform high-quality printing.", "Solution to Problem (1) According to the present invention, there is provided: a printing blanket that is configured to pick up ink, which has been applied to a printing original plate in accordance with a printing pattern, from the printing original plate by being pressed against the printing original plate and then deliver the picked-up ink to a to-be-printed surface by being pressed against the to-be-printed surface, and thereby print the printing pattern on the to-be-printed surface, the printing blanket including a double-layer structure having: a flexible elastic body containing silicone oil;", "and a lesser-flexible coating layer containing silicone oil and covering a part of a surface of the elastic body.", "(2) With regard to (1) described above, the elastic body has a cylindrical shape, and the coating layer covers an outer circumferential surface of the main body.", "(3) With regard to (1) described above, the elastic body has a substantially semi-cylindrical shape, a substantially conical shape, or a substantially pyramidal shape, and the coating layer covers a predetermined area of the elastic body containing an apex thereof.", "(4) With regard to (3) described above, the thickness of the coating layer is greater at the apex of the elastic body and in the vicinity of the apex than at a position away from the apex.", "(5) Further, according to the present invention, there is provided: a printing device including: the printing blanket of any one of (1) through (4);", "a pad mounting unit on which the printing blanket is disposed;", "a moving unit configured to movably support the pad mounting unit;", "a controller configured to control movement of the moving unit;", "and a main body in which the moving unit and the controller are disposed.", "(6) Further, according to the present invention, there is provided: a method of manufacturing a printing blanket including an elastic body having a substantially semi-cylindrical shape and a sheet bonded to a side surface of the elastic body having a substantially arcuate cross section, the method including the steps of: molding an elastic body having a substantially semi-cylindrical shape;", "forming a sheet having a predetermined size;", "placing the sheet on a flat surface;", "pressing a side surface of the elastic body against the placed sheet;", "and applying an adhesive to one or both of the side surface of the elastic body and a surface of the sheet against which the elastic body is to be pressed, prior to the pressing step;", "wherein the sheet is bonded to the side surface of the elastic body in the pressing step.", "(7) With regard to (6) described above, the method further includes the step of applying a mold release agent to any one of the side surface of the elastic body, the surface of the sheet against which the elastic body is to be pressed, and the adhesive.", "(8) With regard to (6) or (7) described above, the sheet and the elastic body contain silicone oil, and the sheet is less flexible than the elastic body.", "Advantageous Effects of Invention (i) A printing blanket according to the present invention includes a double-layer structure having a flexible elastic body and a lesser-flexible coating layer covering a part of the surface of the elastic body, and therefore excellently fits to a curved to-be-printed surface.", "Thus, when the printing blanket is deformed, silicone oil contained in the elastic body is substantially blocked by the lesser-flexible coating layer covering the surface of the elastic body, which makes the silicone oil less likely to come out to the surface of the coating layer.", "Accordingly, it is possible to solve the problems (a) through (d) described above.", "The number of coating layers is not limited to one.", "That is, in the case where two, three, or more coating layers are provided, the printing blanket has a three-layer structure, a four-layer structure, or a multi-layer structure having more than four layers.", "It should be noted that, in this specification, an elastic body is not limited to those in which the relationship between a load applied thereto and the amount of deformation due to the applied load is liner, but may include those in which that relationship is non-linear and which returns to the original shape immediately after or with a delay of a predetermined time period from when a load having been applied thereto is removed.", "Further, “flexible”", "and “soft”", "refer to a property of being easily deformed by application of a relatively lower load.", "For example, in the case of the materials that linearly deform elastically, “flexible”", "and “soft”", "are equivalent to having a low elastic modulus.", "On the other hand, “lesser-flexible”", "and “hard”", "refer to a property of requiring a “relatively higher load”", "to be applied for deformation compared to that required by a substance that is “flexible”", "or “soft.”", "(ii) Further, since the thickness of the coating layer is greater at the apex of the elastic body, which is more likely to be worn (degraded or damaged) due to a higher load applied thereto, than in the other area, it is possible to prevent the service life from being reduced due to local wear.", "(iii) A printing device according to the present invention has a printing blanket that solves the problems (a) through (e) described above, and therefore can print a clean printing pattern at low cost.", "(iv) According to a method of manufacturing a printing blanket of the present invention, the side surface of an elastic body is pressed against a sheet disposed on a flat surface, and thus a printing blanket including an elastic body having a side surface with the sheet bonded thereto is manufactured.", "That is, the lowermost portion of the side surface of the elastic body comes into contact (line contact) with the sheet.", "Then, as the elastic body is pressed further, the contact area gradually expands from that position.", "Therefore, air is prevented from being trapped on the contact surface (i.e., the bonding surface).", "Accordingly, it is possible to pick up ink, which has been applied to a printing original plate in accordance with a printing pattern, from the printing original plate accurately (i.e., while preventing a part of the ink from not being picked up (from remaining thereon)), and transfer the ink to a to-be-printed surface accurately.", "The sheet can be manufactured at low cost, and it is easy to remove a degraded or damaged sheet from the elastic body and bond a new sheet thereto.", "This allows the elastic body to be used repeatedly and thereby achieves low printing costs.", "(v) Further, a mold release agent may be applied to any one of the side surface of the elastic body, the surface of the sheet against which the elastic body is pressed, and the adhesive so as to facilitate replacement of sheets.", "It should be noted that the elastic body is made of the same material as related-art printing blankets.", "Further, although the material of the sheet is not particularly limited, the sheet is capable of picking up ink, which has been applied to a printing original plate (not shown) in accordance with a printing pattern, from the printing original plate when being pressed against the printing original plate, and is capable of delivering the picked-up ink to a to-be-printed surface when being pressed against the to-be-printed surface.", "Accordingly, the sheet has the substantially same function as the elastic body.", "(vi) Moreover, the sheet has elasticity (flexibility) so as to excellently fit to a curved to-be-printed surface.", "Thus, when the elastic body is deformed, silicone oil contained in the elastic body is substantially blocked by the lesser-flexible sheet covering the surface of the elastic body, which makes the silicone oil less likely to come out to the surface of the coating layer.", "Accordingly, it is possible to solve the problems (a) through (e) described above.", "(vii) The sheet may be less flexible than the sheet in order to make the substantial blocking effect by the sheet more pronounced.", "The present invention, however, is not limited thereto.", "BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a perspective view illustrating a printing blanket according to Example 1 in Embodiment 1 of the present invention.", "FIG. 2 is a cross-sectional view illustrating a printing blanket according to Example 2 in Embodiment 1 of the present invention.", "FIG. 3 is a cross-sectional view illustrating a printing blanket according to Example 3 in Embodiment 1 of the present invention.", "FIG. 4 is a schematic front view illustrating a printing device according to Embodiment 2 of the present invention.", "FIG. 5 illustrates a method of manufacturing a printing blanket according to Embodiment 3 of the present invention, wherein (a) of FIG. 1 is a perspective view of an elastic body, and (b) is a perspective of a sheet.", "FIG. 6 shows front views for illustrating respective steps of the method of manufacturing a printing blanket according to Embodiment 3 of the present invention.", "FIG. 7 is a front view for illustrating another example of the method of manufacturing a printing blanket according to Embodiment 3 of the present invention.", "FIG. 8 shows front views for illustrating respective steps of the method of manufacturing a printing blanket according to Embodiment 4 of the present invention.", "DESCRIPTION OF EMBODIMENTS Embodiment 1: Printing Blanket FIGS. 1 through 3 illustrate a printing blanket according to Embodiment 1 of the present invention.", "More specifically, FIG. 1 is a schematic perspective view of Example 1;", "FIG. 2 is a schematic cross-sectional view of Example 2;", "and FIG. 3 is a schematic cross-sectional view of Example 3.", "EXAMPLE 1 Referring to FIG. 1 , a printing blanket 1 according to Example 1 has a double-layer structure formed of an elastic body la having a cylindrical shape, and a coating layer 1 d covering an outer circumferential surface 1 b of the elastic body 1 a. The elastic body 1 a and the coating layer 1 d contain silicone oil in order to ensure transfer (pick-up and deliver) of ink and to impart elasticity (flexibility) thereto.", "The coating layer 1 d is harder (contains a smaller amount of silicone oil) than the elastic body 1 a. Accordingly, the elastic body 1 a is easily deformed, and the coating layer 1 d is deformed in accordance with deformation of the elastic body 1 a .", "Therefore, the printing blanket 1 excellently fits to the curved to-be-printed surface.", "Further, when the printing blanket 1 is deformed, the silicone oil contained in the elastic body 1 a is substantially blocked by the coating layer 1 d surrounding the elastic body 1 a .", "Also, the content of the silicone oil in the coating layer 1 d is small.", "Therefore, the silicone oil is less likely to come out to a surface 1 e of the coating layer 1 d. It should be noted that, in the present invention, the number of coating layers 1 d is not limited to one, and additional one, two, or more coating layers may be provided on top of the coating layer 1 d .", "In this case, the printing blanket 1 has a three-layer structure, a four-layer structure, or a multi-layer structure having more than four layers.", "The coating layer 1 d is bonded to the elastic body 1 a .", "Therefore, in the case where the coating layer 1 d is worn (degraded or damaged), the entire or a part of the worn coating layer 1 d may be removed such that a new coating layer may be formed thereon by using a coating process or the like.", "In this case, the printing blanket 1 has a double-layer structure formed of the original elastic body 1 a and a new coating layer, or has a three-layer structure formed of the original elastic body 1 a , a part of the worn original coating layer 1 d , and a new coating layer.", "It should be noted that, although the entire (360 degrees) outer circumferential surface of the elastic body 1 a is covered by the coating layer 1 d in the above description, the present invention is not limited thereto.", "For example, half the outer circumferential surface (180 degrees) or a third of the outer circumferential surface (120 degrees) of the elastic body 1 a may be covered by the coating layer 1 d .", "Further, in place of a cylindrical shape, the elastic body 1 a may have a semi-cylindrical shape such that a part or a front portion of the arcuate surface thereof may be covered by a coating layer.", "Since the printing blanket 1 is formed such that the silicone oil is less likely to come out to the surface 1 e , the following advantageous effects are obtained.", "(A) Ink applied to a printing original plate (not shown) is reliably transferred to the printing blanket 1 .", "This allows a printing pattern (not shown) to be clearly printed on a to-be-printed surface.", "(B) Ink is prevented from accumulating on the printing original plate (not shown), whereby the printing original plate is prevented from being contaminated.", "This allows a printing pattern to be printed clean without any smear (not shown).", "(C) Further, there is no need to frequently clean the printing original plate (not shown), which prevents the surface thereof being roughened and thus extends the service life thereof.", "This reduces the frequency of replacing with a new printing original plate, resulting in reduced printing costs (equipment costs).", "(D) In the case where the coating layer is worn (degraded or damaged), the printing blanket can be used continuously only by replacing the entire or a part of the coating layer 1 d without replacing elastic bodies, which results in low material costs.", "(E) Further, it is possible to print a printing pattern across a wide area on a curved surface using a single printing blanket 1 .", "This simplifies the printing process and thereby reduces the printing costs.", "This also makes it possible to impart design properties to the printing pattern and thereby enhances the commercial value of the print object.", "(F) Furthermore, even in the case of applying a surface treatment such as coating onto the to-be-printed surface, since there is little silicone oil adhering the to-be-printed surface, the coating is prevented from being repelled by the silicone oil, which allows a high-quality to-be-printed surface (coating surface) to be obtained.", "EXAMPLE 2 Referring to FIG. 2 , a printing blanket 2 according to Example 2 has a double-layer structure formed of an elastic body 2 a having a substantially quadrangular pyramidal shape, and a coating layer 2 d covering a predetermined area of side faces 2 b of the elastic body 2 a , which predetermined area contains an apex 2 c of the elastic body 2 a. The elastic body 2 a has a substantially arcuate triangular cross section with the side faces 2 b projecting outward.", "The adjacent side faces 2 b are smoothly connected to each other, and the apex 2 c where the four side faces 2 b meet has a substantially partial spherical shape.", "The elastic body 2 a and the coating layer 2 d contain silicone oil in order to ensure transfer (pick-up and deliver) of ink.", "The coating layer 2 d is harder than the elastic body 2 a. Accordingly, the elastic body 2 a is easily deformed, and the coating layer 2 d is deformed in accordance with deformation of the elastic body 2 a .", "Therefore, as in the case of the printing blanket 1 of Example 1, the printing blanket 2 excellently fits to the curved to-be-printed surface, and the silicone oil is less likely to come out to a surface 2 e of the coating layer 2 d. It should be noted that, although a part of the side faces 2 b containing the apex 2 c of the elastic body 2 a is covered by the coating layer 2 d in the above description, the present invention is not limited thereto.", "The entire side faces 2 b may be covered by the coating layer 2 d .", "Further, in place of a substantially quadrangular pyramidal shape, the elastic body 2 a may have a shape similar to a three-sided pyramid, or a five or more-sided pyramid.", "The elastic body 2 a may have a conical shape with a rounded apex.", "EXAMPLE 3 Referring to FIG. 3 , a printing blanket 3 according to Example 3 has a double-layer structure formed of an elastic body 3 a having a hemispherical shape, and a coating layer 3 d covering a predetermined area of an outer surface 3 b of the elastic body 3 a , which predetermined area contains an apex (i.e., a south pole in FIG. 3 ) 3 c of the elastic body 3 a. The elastic body 3 a and the coating layer 3 d contain silicone oil in order to ensure transfer (pick-up and deliver) of ink.", "The coating layer 3 d is harder than the elastic body 3 a .", "Further, since the apex 3 c and a portion in the vicinity of the apex 3 c are more likely to be worn (degraded or damaged) due to high pressure applied thereto, the thickness of the coating layer 3 d is greater in this area than in the area away from the apex 3 c. Therefore, as in the case of the printing blanket 1 of Example 1, the printing blanket 3 excellently fits to the curved to-be-printed surface, and the silicone oil is less likely to come out to a surface 3 e of the coating layer 3 d .", "Further, although the apex 3 c and a portion in the vicinity of the apex 3 c are more likely to be worn due to high pressure that is applied thereto due to a pressing motion upon picking up the ink and upon delivering the ink to the to-be-printed surface, since the thickness of the coating layer 3 d is greater in the vicinity of the apex 3 c , the service life of the printing blanket 3 is extended.", "Further, only by forming a new coating layer for only a worn portion or only a predetermined area containing the worn portion, the original printing blanket 3 and the remaining portion of the original coating layer 3 d can be used continuously.", "Therefore, with inexpensive repairs, the printing blanket 3 can be used for a long period of time.", "Furthermore, as in the case of the printing blanket 1 , a wide area of the coating layer 3 d may be replaced.", "This results in low component costs.", "It should be noted that the shape of the elastic body 3 a is not limited and may have a shape similar to a cone or pyramid, or a semi-cylindrical shape.", "Further, the size of the area covered with the coating layer 3 d is not limited as long as the area contains the apex 3 c. Embodiment 2: Printing Device FIG. 4 is a schematic front view illustrating a printing device according to Embodiment 2 of the present invention.", "Referring to (a) of FIG. 4 , a printing device 10 includes a main body 11 , a moving unit 12 , a pad mounting unit 13 , a controller 14 , and the printing blanket 2 (see Example 2).", "The main body 11 includes a main body base 11 a , a main body stand 11 b fixed to the main body base 11 a , and a main body rail 11 c fixed to the upper end of the main body stand 11 b. The moving unit 12 includes an X-direction moving beam 12 x movably supported by (disposed on or suspended on) the main body rail 11 c , a Y-direction moving beam 12 y movably supported by (disposed on or suspended on) the X-direction moving beam 12 y , and a lifting unit 12 z that is disposed on the Y-direction moving beam 12 y and is configured to lift and lower the pad mounting unit 13 .", "The pad mounting unit 13 includes a mounting bar 13 a configured to be lifted or lowered by the lifting unit 12 z , and a mounting plate 13 b fixed to the lower end of the mounting bar 13 a .", "The printing blanket 2 is mounted on the lower surface of the mounting plate 13 b. The controller 14 moves the moving unit 12 so as to perform printing in accordance with an entered predetermined printing procedure.", "That is, the printing blanket 2 is moved to a position facing a printing original plate (i.e., an image plate) 4 on which ink is disposed in accordance with a printing pattern, and is lowered to be pressed against the printing original plate 4 , so that the ink is transferred to (picked up by) the printing blanket 2 .", "Then, the printing blanket 2 is lifted, is moved to a position facing a print object 5 , and is lowered so as to transfer (deliver) the ink to a to-be-printed surface.", "Thus, a printing pattern is printed on the surface of the print object 5 .", "Thus, since the printing device 10 includes the printing blanket 2 (Example 2), it is possible to print a clear and clean printing pattern on the to-be-printed surface at low costs.", "It is also possible to enhance the commercial value of the print object by printing a printing pattern with design properties imparted thereto.", "It should be noted that the printing blanket 1 or the printing blanket 3 may be used in place of the printing blanket 2 .", "Further, the moving unit 12 illustrated in the above description is formed of members that move in three directions, respectively.", "However, the present invention is not limited there to, and the moving unit 12 may include a robot whose distal end is movable in three directions.", "Referring to (b) of FIG. 4 , a printing device 20 includes a main body 21 , a moving unit 22 , a pad supporting unit 23 , a controller 24 , and the printing blanket 1 (see Example 1).", "The main body 21 includes a main body base 21 a , a main body stand 21 b fixed to the main body base 21 a , and a main body rail 21 c fixed to the upper end of the main body stand 21 b. The moving unit 22 is movably supported by (suspended on) the main body rail 11 c , and is configured to move itself in accordance with a control signal from the controller 24 .", "The pad supporting unit 23 has an end mounted on the moving unit 22 and the other end rotatably supporting the center of the printing blanket 1 .", "The controller 24 moves the moving portion 22 so as to perform printing in accordance with an entered predetermined printing procedure.", "That is, when the moving unit 22 moves rightward, the printing blanket 1 rotates while being pressed against a printing original plate (i.e., an image plate) 4 on which ink is disposed in accordance with a printing pattern, so that the ink is transferred to (picked up by) the printing blanket 1 .", "Then, when the moving unit 22 moves leftward, the printing blanket 1 rotates while being pressed against a print object 5 so as to transfer (deliver) the ink to a to-be-printed surface.", "Thus, a printing pattern is printed on the surface of the print object 5 .", "In order to prevent the surface le of the printing blanket 1 from sliding with respect to the surface of the printing original plate 4 and to prevent the surface le of the printing blanket 1 from sliding with respect to the surface of the print object 5 , the moving speed of the moving unit 22 is equal to the peripheral speed of the surface 1 e. Thus, since the printing device 20 includes the printing blanket 1 (Example 1), it is possible to print a clear and clean printing pattern on the to-be-printed surface at low costs.", "It is also possible to enhance the commercial value of the print object by printing a printing pattern with design properties imparted thereto.", "Embodiment 3: Method of Manufacturing Printing Blanket FIGS. 5 through 7 illustrate a method of manufacturing a printing blanket according to Embodiment 3 of the present invention.", "More specifically, (a) of FIG. 5 is a schematic perspective view of a part (an elastic body);", "(b) of FIG. 5 is a schematic perspective view of a part (a sheet);", "FIG. 6 shows front views for illustrating respective steps;", "and FIG. 7 is a schematic front view of another example.", "It should be noted that the same components are denoted by the same reference signs throughout the drawings, and a description thereof will be partially omitted.", "Further, the drawings are schematically illustrated, and the present invention is not limited to the shapes shown in the drawings (in particular, the thickness of the sheet is illustrated with exaggeration).", "Referring to FIGS. 5 through 7 , a printing blanket 30 has a substantially semi-cylindrical shape, and has a double-layer structure formed of an elastic body 31 and a sheet 32 bonded to the side surface of the elastic body 31 .", "The elastic body 31 includes a side face 31 a defining a convex surface, another side face 31 b that is plane-symmetric to the side face 31 a , a ridge line 31 c (technically, this portion has a certain width, but is referred to as a “line”", "for explanation purposes) smoothly connecting between the side surface 31 a and the side surface 31 b , and a mounting surface 1 d serving as a mounting surface to be attached to a printing apparatus (not shown).", "It should be noted that the ridge line 31 c defines the lowermost end of the elastic body 31 .", "Further, the cross sections of the side faces 31 a and 31 b do not have a perfect semicircular shape, but have a bullet shape (see (a) of FIG. 5 and (c) of FIG. 6 ).", "The sheet 32 has a rectangular shape with a predetermined thickness (e.g., 1 mm), and is capable of picking up ink, which has been applied to a printing original plate (not shown) in accordance with a printing pattern, from the printing original plate when being pressed against the printing original plate, and is capable of delivering the picked-up ink to a to-be-printed surface (not shown) when being pressed against the to-be-printed surface.", "The material (substance) thereof is not particularly limited.", "The elastic body 31 is also capable of picking up ink, which has been applied to a printing original plate (not shown) in accordance with a printing pattern, from the printing original plate through the sheet 32 when being pressed against the printing original plate, and is capable of delivering the picked-up ink to a to-be-printed surface (not shown) through the sheet 32 when being pressed against the to-be-printed surface.", "The material (substance) thereof is not particularly limited.", "Next, a description will be given of a manufacturing method with reference to FIG. 6 .", "An elastic body 31 having a substantially semi-cylindrical shape (a bullet-shaped cross section) is molded.", "Also, a sheet having a predetermined size (thickness, vertical length, and horizontal length) is formed.", "The sheet may be obtained by molding a sheet into a predetermined size, or by cutting a large sheet into a rectangle of a predetermined size.", "Subsequently, the sheet 32 is placed on a flat surface 33 (see (b) of FIG. 5 ).", "Then, an adhesive (not shown) is applied to the side faces 31 a and 1 b and the ridge line 31 c , and the elastic body 31 is lowered in the normal direction of the flat surface 33 so as to be pressed against the sheet 32 (see (a) and (b) of FIG. 6 ).", "Thus, the ridge line 31 c of the elastic body 31 first comes into contact (line contact) with the sheet 32 .", "Then, as the elastic body 31 is pressed further, the elastic body 31 (and the sheet 32 which deforms in accordance with deformation of the elastic body 31 ) is deformed.", "Thus the contact location gradually moves in the direction away from the ridge line 31 c such that the contact area expands (the contact surface expands so as to cover a greater area of the side faces 31 a and 1 b ).", "This prevents air from being trapped on the contact surface (i.e., the bonding surface).", "Then, when the entire surface of the sheet 32 comes into contact with (is bonded to) the elastic body 31 , lowering of the elastic body 31 is stopped.", "Then, immediately after stopping lowering of the elastic body 31 , or after maintaining the elastic body 31 in a pressed state for a predetermined time period after stopping lowering of the elastic body 31 , the elastic body 31 is lifted.", "Thus, the elastic body 31 returns to the original shape.", "In this way, a printing blanket 30 formed of the elastic body 31 with the sheet 32 bonded thereto (see (c) of FIG. 6 ) is obtained.", "Since the printing blanket 30 does not have any bubble (that is small enough to be invisible to the naked eye) trapped on the bonding surface of the sheet 32 , it is possible to prevent a part of the to-be-printed surface from not being printed (prevent blank portions from remaining on the to-be-printed surface) and therefore to perform high-quality printing.", "Moreover, the sheet 32 can be manufactured at low cost, and it is easy to bond the sheet 32 to the elastic body 31 .", "Therefore, even if the surface of the sheet 32 is locally degraded or damaged due to use, the degraded sheet 32 can be removed and replaced with a new sheet 32 at low cost.", "This allows high-quality printing to be performed continuously at low cost.", "On the other hand, in the case of forming, in place of the sheet 32 , a coating body having an inner surface that has a shape matching the shapes of the side faces 31 a and 1 b of the elastic body 31 and having a predetermined thickness by molding using a die, it is necessary to form a die for each shape of the elastic body 31 , resulting in an increase in the manufacturing cost of the printing blanket.", "Further, when bonding the coating body to the elastic body 31 , air is trapped between the inner surface of the coating body and the side faces 31 a and 1 b of the elastic body 31 , and therefore high-quality printing cannot be performed.", "It should be noted that, although an adhesive is applied to the elastic body 31 before the pressing step, the present invention is not limited thereto.", "An adhesive may be applied to the sheet 32 in place of the elastic body 31 , or to both the sheet 32 and the elastic body 31 .", "Further, the method of applying an adhesive is not particularly limited.", "An adhesive may be applied using a brush, or may be applied by spraying using a spray.", "Further, the sheet 32 may be placed on a concave surface 34 having an arcuate cross section (see FIG. 7 ) in place of the flat surface 33 .", "In this case, as in the case where the elastic body 31 is pressed against the flat surface 33 , since the contact area gradually expands in a predetermined direction, air is prevented from being trapped on the contact surface (i.e., the bonding surface), which allows high-quality printing to be performed.", "Embodiment 4: Method of Manufacturing Printing Blanket FIG. 8 shows front views for illustrating respective steps of the method of manufacturing a printing blanket according to Embodiment 4 of the present invention.", "It should be noted that the same components as those in Embodiment 3 are denoted by the same reference signs, and a description thereof will be partially omitted.", "Referring (a) of FIG. 8 , a sheet 35 has a thickness that gradually increases toward the center thereof in a width direction thereof.", "Further, the sheet 35 is disposed on a recessed surface 36 of a work table 37 .", "The recessed surface 36 is smoothly recessed toward the center thereof in a width direction thereof.", "In this case, since the depth of the recess of the recessed surface 36 varies in accordance with the varying thickness of the sheet 35 in the width direction, the upper surface of the sheet 35 placed on the recessed surface 36 is flat.", "Accordingly, when the elastic body 31 is pressed against the sheet 35 having a flat upper surface, air is prevented from being trapped on the contact surface (i.e., the bonding surface), which allows high-quality printing to be performed.", "Referring to (b) of FIG. 8 , as in the case of Embodiment 3, a printing blanket 40 is formed by pressing the elastic body 31 against the sheet 35 .", "Since the sheet 35 bonded to the printing blanket 40 has a thickness that gradually increases toward the ridge line 31 c gradually, that is, since the sheet 35 has a greater thickness in an area that is more likely to be severely worn, the printing blanket 40 can be used for a longer period of time.", "INDUSTRIAL APPLICABILITY According to the present invention, a printing blanket excellently fits to a curved to-be-printed surface while preventing silicone oil contained in the printing blanket from coming out to the surface of the printing blanket when the printing blanket is deformed.", "Accordingly, the present invention is widely used as printing blankets of various shapes and sizes, and printing devices having the printing blankets.", "Further, a sheet is bonded to an elastic body while preventing air from being trapped therebetween, which allows high-quality printing to be performed.", "Therefore, it is possible to manufacture a printing blanket at low cost.", "Accordingly, the present invention can be widely used a printing blanket manufacturing method for manufacturing printing blankets of various shapes and sizes.", "REFERENCE SIGNS LIST 1 printing blanket (Example 1) 1 a elastic body 1 b outer circumferential surface 1 d coating layer 1 e surface 2 printing blanket (Example 2) 2 a elastic body 2 b side face 2 c apex 2 d coating layer 2 e surface 3 printing blanket (Example 3) 3 a elastic body 3 b outer surface 3 c apex 3 d coating layer 3 e surface 4 printing original plate 5 print object 10 printing device (Embodiment 2) 11 main body 11 a main body base 11 b main body stand 11 c main body rail 12 moving unit 12 x X-direction moving beam 12 y Y-direction moving beam 12 z lifting unit 13 pad mounting unit 13 a mounting bar 13 b mounting plate 14 controller 20 printing device (Embodiment 2) 21 main body 21 a main body base 21 b main body stand 21 c main body rail 22 moving unit 23 pad supporting unit 24 controller 31 elastic body 31 a side face 31 b side face 31 c ridge line 31 d mounting surface 32 sheet 33 flat surface 34 concave surface 35 sheet 36 recessed surface 37 work table 30 printing blanket (Embodiment 3) 40 printing blanket (Embodiment 4)" ]
BACKGROUND AND SUMMARY OF THE PRESENT INVENTION The invention disclosed herein pertains generally to supercharged internal combustion engines, and more particularly to a method and apparatus for bypassing a portion of the air charge supplied to a supercharged internal combustion engine and diverting it to a turbocharger supplying air to the engine. Bypass devices in supercharged internal combustion engines are used mainly in conjunction with turbochargers. Such bypass devices serve to improve the low load characteristics of supercharged internal combustion engines having elevated charge compression ratios, and are used predominantly with four stroke diesel engines which are supercharged by turbochargers. A typical bypass device includes a bypass duct which connects a charging air duct, extending downstream from the compressor of a turbocharger, to an exhaust gas duct emanating from the engine and arranged upstream from the turbine of the turbocharger. Such a bypass device typically also includes a valve arranged in the bypass duct, which valve is used to regulate the flow of air which flows from the charging air duct through the bypass duct to the turbine of the turbocharger. By regulating the flow of air diverted from the charging air duct through the bypass duct to the turbocharger, it is possible to match the absorption capacity of the engine to the characteristics of the compressor so that a higher supercharging pressure is obtained at low loads. At maximum or full load the bypass duct is closed. Between the starting point of the engine and the full load point, the bypass valve is progressively opened as the difference between the absorption capacity of the engine and the compressor's pumping limit or the air/fuel ratio decreases. It is common practice to utilize the pressures upstream and downstream of the bypass duct, the engine speed, and the gas temperature upstream of the turbine as the variables and parameters used in controlling the bypass valve. If the pressure gradient across the bypass duct becomes too small to enable air to flow through the bypass duct, it is possible to use heat exchangers, auxiliary combustion chambers arranged upstream of the turbine, or other means for supplying compressed air to the turbocharger. It is also known to utilize the pulsation energy of the engine exhaust gases to promote the flow of bypass air to the turbocharger. Engines with these known supplemental devices generally have satisfactory acceleration and low load characteristics, but are costly because of the expenses involved in construction. A primary object of the present invention is to provide a method and apparatus for regulating the flow of bypass air through a bypass duct of a turbocharged internal combustion engine, which method and apparatus employ pressure pulsations produced by the periodic, alternating charging of the internal combustion engine to excite periodic pressure differences across the bypass duct, to produce an increased flow of charging air through the bypass duct. Another object of the present invention is to provide a method and apparatus for regulating the flow of bypass air through a bypass duct of a turbocharged internal combustion engine without the use of supplemental devices. Apparatus for regulating a flow of air through a bypass duct of a turbocharged internal combustion engine, according to a preferred embodiment of the present invention, includes a turbocharger and a six-cylinder internal combustion engine. A turbine of the turbocharger drives a compressor which supplies compressed air to the engine through a charging air duct. The charging air duct feeds compressed air from the compressor to an air receiver, which air receiver acts as a damping volume. The air receiver in turn feeds air into two air oscillation pipes, each of which pipes feeds air to one of two inlet manifolds. Each of the inlet manifolds supplies air to three cylinders of the six-cylinder engine through three suction pipes. Six exhaust pipes feed exhaust gases from the cylinders of the six-cylinder engine to an exhaust gas manifold. In addition, two bypass ducts feed compressed air from the inlet manifolds to the exhaust gas manifold. A bypass valve and a non-return valve, which non-return valve prevents backflow, are arranged in each bypass duct, and are used to regulate the flow of compressed air through each bypass duct. During the operation of the engine, the periodic downstroke of the piston in each cylinder produces a periodic suction effect which results in periodic pressure fluctuations propagating into the suction pipes connecting the two inlet manifolds to the engine cylinders. These pressure fluctuations propagate through each of the inlet manifolds and into each of the air oscillation pipes. The natural frequency of the column of air in each air oscillation pipe corresponds to the suction pulsation frequency of the engine in the engine speed range in which a maximum bypass flow rate is required. Thus, the air columns in the air oscillation pipes resonate in this speed range, resulting in the pressure differences across the bypass ducts reaching a maximum value, and the bypass flow rate thereby also reaching a maximum value. BRIEF DESCRIPTION OF THE DRAWINGS Preferred embodiments of apparatus according to the present invention are described with reference to the accompanying drawings wherein like members bear like reference numerals, and wherein: FIG. 1 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a first preferred embodiment of apparatus, according to the present invention, arranged upstream of the engine, for generating periodic pressure differences across a bypass duct, which pressure differences facilitate a flow of air through the bypass duct; FIG. 2 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a second preferred embodiment of apparatus, according to the present invention, which second embodiment is similar to the first embodiment but differs in that the second embodiment includes injectors arranged downstream from the engine; FIG. 3 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a third preferred embodiment of apparatus, according to the present invention, arranged on the downstream side of the engine; FIG. 4 is a cross-sectional view of a fourth preferred embodiment of apparatus, according to the present invention, shown in FIG. 6, which cross-sectional view is taken on the line IV--IV of FIG. 6, and which cross-sectional view shows an injector and a diffuser arranged on the downstream side of a turbocharged, internal combustion engine; FIG. 5 is a cross-sectional view of a fifth preferred embodiment of apparatus, according to the present invention, shown in FIG. 7, which cross-sectional view is taken on the line V--V of FIG. 7, and which cross-sectional view shows an injector, a diffuser, and an air oscillation pipe arranged on the downstream side of a turbocharged internal combusion engine; FIG. 6 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a fourth preferred embodiment of apparatus, according to the present invention; FIG. 7 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a fifth preferred embodiment of apparatus, according to the present invention; and FIG. 8 is a cross-sectional view of an injector arranged within a tower valve, which tower valve functions as a non-return valve. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIG. 1, a first preferred embodiment of apparatus, according to the present invention, includes a six-cylinder internal combustion engine 1, the exhaust gases of which engine are conducted through six exhaust pipes 2 into an exhaust manifold 3. The engine exhaust gases flow from the manifold 3 through an exhaust gas duct 4 toward a turbine 5 of a turbocharger, which turbine drives a compressor 7 through a turbocharger shaft 6. The compressor 7 supplies compressed air to each cylinder of the engine 1. Charging air compressed by the air compressor 7 passes through a charging air duct 8 and a charging air cooler 9 into an air receiver 10, which air receiver functions as a damping volume. The compressed air then flows from the air receiver 10 through two air oscillation pipes 11 into two inlet manifolds 12, each of which manifolds feeds charging air to three cylinders of the engine. Each inlet manifold 12 functions as a resonance volume, the purpose of which resonance volume and the purpose of which air oscillation pipes is explained below. Compressed air from the air receiver 10 is fed to the engine 1 by two parallel flow systems, each of which systems includes an air oscillation pipe 11 and an inlet manifold 12. The periodic suction operation of the engine cylinders produces pressure fluctuations in the suction pipes 13, which suction pipes connect each of the inlet manifolds of each flow system to three engine cylinders. These pressure fluctuations propagate from the suction pipes 13 into the inlet manifold 12 and then into the air oscillation pipe 11 of each system. It is to be noted that the inlet manifold 12 of each flow system is connected by a bypass duct 14 to the exhaust gas manifold 3 which is arranged on the exhaust side of the engine 1. The length of the air oscillation pipe 11 and the bypass duct 14 and the volume of the inlet manifold 12, of each flow system, and of the air receiver 10, are designed so that the natural frequency of the air column in each flow system corresponds to the exciting suction pulsation frequency of the engine in the speed range in which a maximum bypass flow rate is required. Resonance therefore occurs in the aforementioned speed range so that the pressure differences across each bypass duct 14 reach a maximum, and therefore the bypass air flow rates reach a maximum value. A bypass valve 15, of known construction, and a non-return valve 16, which prevents back flow, are arranged in each bypass duct 14 of each parallel flow system to control and regulate the bypass flow. A Borda or re-entrant orifice or some other rectifying element, in which flow in the reverse direction is zero or greatly restricted, can also be used as a non-return valve. The aforementioned rectifying element ensures that, when averaged with respect to time, air only flows from the inlet manifold 12 toward and into the exhaust manifold 3. Pressures upstream and downstream of each bypass duct 14, an engine or turbocharger speed, and a gas temperature upstream of the turbine can be used as reference variables or controlling variables for actuating the bypass valve 15. It is advantageous to provide a charging air cooler, or coolers, between each inlet manifold 12 and the corresponding cylinders fed by the inlet manifold so that the energy of the bypass air stream is not reduced by cooling. The pressure of the engine exhaust gases in the exhaust manifold 3 may be regarded as constant by virtue of the relatively large volume of the manifold. The pressure difference across each bypass duct 14 can therefore be regarded as depending entirely on the excess of the air pressure in each inlet manifold 12 over the constant gas pressure in the exhaust manifold 3. With reference to FIG. 2, a second preferred embodiment of apparatus according to the present invention, which is similar to the first preferred embodiment, utilizes pressure fluctuations of the engine exhaust gases on the exhaust side of the six-cylinder internal combustion engine 1, in addition to charging air pressure fluctuations on the inlet side of the engine 1, for increasing the pressure differences across the bypass ducts 14. To obtain the maximum possible pressure differences it is essential that the exhaust gas pressure fluctuations are out of phase with the corresponding charging air pressure fluctuations in the inlet manifolds 12, i.e., that a pressure peak on the inlet side always coincides with a pressure valley on the exhaust side. The exhaust pipes 2 of every three adjacently disposed cylinders of the engine 1 merge into exhaust manifolds 17 and 18. Each of the two bypass ducts 14, each of which ducts includes a valve 15 and a non-return valve 16, connects one of the two inlet manifolds 12 to a corresponding exhaust manifold 17, 18. An injector 19 is provided at each of the places where the bypass ducts 14 merge into their respective manifolds 17, 18. These injectors are utilized to increase the total pressure differences across each of the bypass ducts 14, thereby increasing the flow rates of charging air through the bypass ducts 14. With reference to FIG. 3, a third preferred embodiment of apparatus, according to the present invention, also includes a six-cylinder internal combustion engine 1, the exhaust gases of which engine are conducted through exhaust pipes 2 to two exhaust manifolds 17 and 18. Three cylinders of the engine 1 feed exhaust gases into manifold 17, and three cylinders feed exhaust gases into manifold 18. Each of the exhaust manifolds includes an injector 19 and each of the exhaust manifolds conducts engine exhaust gases to a turbocharger. The turbocharger of the third preferred embodiment includes a turbine 5 which drives a compressor 7 through a turbocharger shaft 6. The compressor 7 feeds compressed air to the engine 1 through a charging air duct 8. The charging air duct 8 bifurcates at one point, one fork of the bifurcated duct 8 feeding air through a charging air cooler 9 to a single inlet manifold 12, and the other fork of the bifurcated duct 8 feeding air to a single bypass duct 14. The single inlet manifold 12 supplies compressed charging air to each of the cylinders of the six-cylinder engine 1. The single bypass duct 14, which includes a valve 15 for regulating the flow of compressed air through the duct 14, feeds compressed air to a bypass air receiver 20 which is arranged on the exhaust side of the engine 1 and which acts as a damping volume. The bypass air receiver in turn feeds compressed air to each of two air oscillation pipes 11. Each of the pipes 11 includes a non-return valve 16 at the point where each pipe 11 merges into the bypass air receiver 20. The pipes 11 each feed compressed air to one of two bypass inlet manifolds 21, each of which bypass inlet manifolds feeds air into one of the exhaust manifolds 17, 18. The injectors 19 are located at the points where the bypass inlet manifolds merge into the exhaust manifolds 17, 18. In the third preferred embodiment, resonance oscillation of air columns in the air oscillation pipes 11, which oscillation is amplified by the action of the injectors 19 arranged in the two exhaust manifolds 17 and 18, is utilized to increase the flow of air through the bypass duct 14. That is, exhaust gas pressure fluctuations, which fluctuations are amplified or reinforced by the action of the injectors 19 in the exhaust manifolds 17 and 18, impart an oscillation to the air columns in the air oscillation pipes 11 and in the bypass inlet manifolds 21. The oscillation of the air columns in conjunction with the periodically occurring negative pressures of the exhaust gases emanating from the engine, negative with respect to the bypass air receiver 20, serve to induce bypass air to flow through the non-return valves 16, the air oscillation pipes 11, the bypass inlet manifolds 21, the exhaust manifolds 17 and 18, and into the turbine 5. In order for the third embodiment to operate efficiently, the air oscillation pipes 11 and the bypass inlet manifolds 21 must be so arranged that the natural frequency of the air columns therein corresponds to the frequency of the engine exhaust gas surges in the selected range of low load speeds, where high bypass flow rates are needed. With reference again to FIG. 3, it should be noted that the non-return valves 16 or equivalent rectifying elements can also be arranged between the bypass inlet manifolds 21 and the exhaust manifolds 17 and 18. With reference to FIG. 4, an apparatus which is included in a fourth preferred embodiment of the present invention uses the principle of reflection of periodic pressure waves at an open end of a tube to excite periodic induction waves. The apparatus includes an injector 19 arranged at the end of a short exhaust pipe 2, which injector adjoins an open-ended diffuser 22. The diffuser 22 extends into an exhaust manifold 3 in which a practically constant gas pressure prevails. A non-return valve 16 is arranged within a pipe which connects a bypass air receiver 20 to the injector 19. In operation, periodic pressure fluctuations of the exhaust gases emanating from the engine 1 are reinforced by the injector 19. Further reinforcement of the periodic pressure fluctuations is effected by reflection of the pressure waves traveling through the diffuser 22 at the open end of the diffuser 22, to produce large periodic pressure differences between the bypass air receiver 20 and the injectors 19. The action of the induction waves increases with increasing length of the duct between the injector 19 and the diffuser 22. If other means are sufficient to ensure adequate delivery of the bypass air it is possible to dispense with the injector action so that the loss of head of exhaust gases can be minimized. With reference again to FIG. 4, it is to be noted that an injector 19 is not essential. Rather, it is possible for the confluence of the exhaust pipe 2, emanating from the engine 1, and the bypass duct to be constructed so that the two flows, i.e., the flow of exhaust gases through the exhaust pipe 2 and the bypass flow of compressed air in the bypass duct, are oriented in the same direction in the region where the two flows mix. For example, the confluence of the exhaust pipe and the bypass duct may be in the form of a cylindrical exhaust pipe which enters the bypass duct or in the form of two ducts which join at an acute angle in the flow direction. With reference to FIG. 5, a modification of the apparatus shown in FIG. 4 includes an air oscillation pipe 11 arranged between the bypass air receiver 20 and the injector 19 so that a reinforced delivery of compressed air is obtained. As shown in FIG. 5, the non-return valve 16 may be arranged adjacent the bypass air receiver 20 rather than adjacent the injector 19. With reference to FIG. 6, a fourth preferred embodiment of apparatus, according to the present invention, which incorporates the device shown in FIG. 4, includes a six-cylinder internal combustion engine 1. Exhaust gases from the engine 1 flow through six exhaust pipes 2 into six injectors 19. The exhaust gases flowing through each of the injectors 19 flow, respectively, into six diffusers 22, the ends of which diffusers open into an exhaust manifold 3. The exhaust manifold 3 conducts the exhaust gases to a turbine 5 of a turbocharger, which turbine drives a compressor 7 through a turbocharger shaft 6. Compressed air supplied by the compressor 7 flows through a duct which feeds compressed air to a charging air duct 8 as well as to a bypass duct 14. The compressed air flowing through the charging air duct 8 flows through a charging air cooler 9 and into an inlet manifold, which inlet manifold feeds compressed air to each cylinder of the engine 1. The bypass duct 14, which includes a valve 15 for regulating the flow of air through the duct 14, feeds compressed air to a bypass air receiver arranged on the exhaust side of the engine 1. Six pipes connect the bypass air receiver to the six diffusers 19 which conduct both engine exhaust gases from the exhaust pipes 2, and compressed air from the bypass air receiver, to the exhaust manifold 3. A non-return valve 16 is arranged in each of the six pipes. With reference to FIG. 7, a fifth preferred embodiment of apparatus according to the present invention, which incorporates the device shown in FIG. 5, includes a six-cylinder internal combustion engine 1. Exhaust gases from the engine 1 flow through six exhaust pipes 2 into six injectors 19. The exhaust gases flowing through each of the injectors 19 flow, respectively, into six diffusers 22, the ends of which diffusers open into an exhaust manifold 3. The exhaust manifold 3 conducts the exhaust gases to a turbine 5 of a turbocharger, which turbine drives a compressor 7 through a turbocharger shaft 6. The compressor 7 feeds compressed air to the engine 1 through a charging air duct 8. The charging air duct 8 bifurcates at one point, one fork of the bifurcated duct 8 feeding air through a charging air cooler 9 to a single inlet manifold, and the other fork of the bifurcated duct 8 feeding air to a single bypass duct 14. The single inlet manifold supplies compressed charging air to each of the cylinders of the six-cylinder engine 1. The bypass duct 14, which includes a valve 15 for regulating the flow of compressed air through the duct 14, feeds compressed air to a bypass air receiver 20, arranged on the exhaust side of the engine 1. The bypass air receiver in turn feeds compressed air to each of two air oscillation pipes 11. Each of the air oscillation pipes 11 feeds air to one of two bypass inlet manifolds 21, and each of the bypass inlet manifolds 21 is connected by three pipes to three of the six injectors 19. Thus, the injectors 19 feed a mixture of exhaust gases from the engine 1 and compressed air from the inlet manifolds 21 into the six diffusers 22, which diffusers feed this mixture into the exhaust manifold 3. The exhaust manifold then feeds this mixture to the turbihe 5. With reference to FIG. 8, a tower valve 23 may be used as a rectifying element, i.e., as a non-return valve, in the embodiments of the present invention which employ injectors. This valve includes a plurality of serially arranged plate valves 24, each of which plate valves has an easily movable, low-inertia valve plate 25. An injector nozzle 26 is centrally arranged with the tower valve 23. The tower valve 23 is particularly suitable to the present invention because the volume between the end of the injector nozzle 26, where minimum pressure prevails, and the valve plates 25, can be kept very small so that pressure differences are able to act fully and a particularly good delivery effect is obtained. The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive. Variations and changes may be made by those skilled in the art without departing from the spirit of the present invention.
A method and apparatus for regulating a bypass flow of a turbocharged internal combustion engine is disclosed. A first preferred embodiment of the apparatus includes an air receiver which is in fluid communication with a turbocharger and an air oscillation pipe. The air oscillation pipe is in fluid communication with an inlet manifold, which inlet manifold is in fluid communication with a bypass duct and the turbocharged engine. The bypass duct is in fluid communication with the turbocharger. Pressure pulsations emanating from the engine propagate into the inlet manifold and the air oscillation pipe causing an air column within the inlet manifold and air oscillation pipe to oscillate. Periodic oscillations of the air column produces periodic pressure differences across the bypass duct, facilitating a bypass flow of air through the bypass duct.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "BACKGROUND AND SUMMARY OF THE PRESENT INVENTION The invention disclosed herein pertains generally to supercharged internal combustion engines, and more particularly to a method and apparatus for bypassing a portion of the air charge supplied to a supercharged internal combustion engine and diverting it to a turbocharger supplying air to the engine.", "Bypass devices in supercharged internal combustion engines are used mainly in conjunction with turbochargers.", "Such bypass devices serve to improve the low load characteristics of supercharged internal combustion engines having elevated charge compression ratios, and are used predominantly with four stroke diesel engines which are supercharged by turbochargers.", "A typical bypass device includes a bypass duct which connects a charging air duct, extending downstream from the compressor of a turbocharger, to an exhaust gas duct emanating from the engine and arranged upstream from the turbine of the turbocharger.", "Such a bypass device typically also includes a valve arranged in the bypass duct, which valve is used to regulate the flow of air which flows from the charging air duct through the bypass duct to the turbine of the turbocharger.", "By regulating the flow of air diverted from the charging air duct through the bypass duct to the turbocharger, it is possible to match the absorption capacity of the engine to the characteristics of the compressor so that a higher supercharging pressure is obtained at low loads.", "At maximum or full load the bypass duct is closed.", "Between the starting point of the engine and the full load point, the bypass valve is progressively opened as the difference between the absorption capacity of the engine and the compressor's pumping limit or the air/fuel ratio decreases.", "It is common practice to utilize the pressures upstream and downstream of the bypass duct, the engine speed, and the gas temperature upstream of the turbine as the variables and parameters used in controlling the bypass valve.", "If the pressure gradient across the bypass duct becomes too small to enable air to flow through the bypass duct, it is possible to use heat exchangers, auxiliary combustion chambers arranged upstream of the turbine, or other means for supplying compressed air to the turbocharger.", "It is also known to utilize the pulsation energy of the engine exhaust gases to promote the flow of bypass air to the turbocharger.", "Engines with these known supplemental devices generally have satisfactory acceleration and low load characteristics, but are costly because of the expenses involved in construction.", "A primary object of the present invention is to provide a method and apparatus for regulating the flow of bypass air through a bypass duct of a turbocharged internal combustion engine, which method and apparatus employ pressure pulsations produced by the periodic, alternating charging of the internal combustion engine to excite periodic pressure differences across the bypass duct, to produce an increased flow of charging air through the bypass duct.", "Another object of the present invention is to provide a method and apparatus for regulating the flow of bypass air through a bypass duct of a turbocharged internal combustion engine without the use of supplemental devices.", "Apparatus for regulating a flow of air through a bypass duct of a turbocharged internal combustion engine, according to a preferred embodiment of the present invention, includes a turbocharger and a six-cylinder internal combustion engine.", "A turbine of the turbocharger drives a compressor which supplies compressed air to the engine through a charging air duct.", "The charging air duct feeds compressed air from the compressor to an air receiver, which air receiver acts as a damping volume.", "The air receiver in turn feeds air into two air oscillation pipes, each of which pipes feeds air to one of two inlet manifolds.", "Each of the inlet manifolds supplies air to three cylinders of the six-cylinder engine through three suction pipes.", "Six exhaust pipes feed exhaust gases from the cylinders of the six-cylinder engine to an exhaust gas manifold.", "In addition, two bypass ducts feed compressed air from the inlet manifolds to the exhaust gas manifold.", "A bypass valve and a non-return valve, which non-return valve prevents backflow, are arranged in each bypass duct, and are used to regulate the flow of compressed air through each bypass duct.", "During the operation of the engine, the periodic downstroke of the piston in each cylinder produces a periodic suction effect which results in periodic pressure fluctuations propagating into the suction pipes connecting the two inlet manifolds to the engine cylinders.", "These pressure fluctuations propagate through each of the inlet manifolds and into each of the air oscillation pipes.", "The natural frequency of the column of air in each air oscillation pipe corresponds to the suction pulsation frequency of the engine in the engine speed range in which a maximum bypass flow rate is required.", "Thus, the air columns in the air oscillation pipes resonate in this speed range, resulting in the pressure differences across the bypass ducts reaching a maximum value, and the bypass flow rate thereby also reaching a maximum value.", "BRIEF DESCRIPTION OF THE DRAWINGS Preferred embodiments of apparatus according to the present invention are described with reference to the accompanying drawings wherein like members bear like reference numerals, and wherein: FIG. 1 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a first preferred embodiment of apparatus, according to the present invention, arranged upstream of the engine, for generating periodic pressure differences across a bypass duct, which pressure differences facilitate a flow of air through the bypass duct;", "FIG. 2 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a second preferred embodiment of apparatus, according to the present invention, which second embodiment is similar to the first embodiment but differs in that the second embodiment includes injectors arranged downstream from the engine;", "FIG. 3 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a third preferred embodiment of apparatus, according to the present invention, arranged on the downstream side of the engine;", "FIG. 4 is a cross-sectional view of a fourth preferred embodiment of apparatus, according to the present invention, shown in FIG. 6, which cross-sectional view is taken on the line IV--IV of FIG. 6, and which cross-sectional view shows an injector and a diffuser arranged on the downstream side of a turbocharged, internal combustion engine;", "FIG. 5 is a cross-sectional view of a fifth preferred embodiment of apparatus, according to the present invention, shown in FIG. 7, which cross-sectional view is taken on the line V--V of FIG. 7, and which cross-sectional view shows an injector, a diffuser, and an air oscillation pipe arranged on the downstream side of a turbocharged internal combusion engine;", "FIG. 6 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a fourth preferred embodiment of apparatus, according to the present invention;", "FIG. 7 is a schematic view of a turbocharged six-cylinder internal combustion engine which includes a fifth preferred embodiment of apparatus, according to the present invention;", "and FIG. 8 is a cross-sectional view of an injector arranged within a tower valve, which tower valve functions as a non-return valve.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIG. 1, a first preferred embodiment of apparatus, according to the present invention, includes a six-cylinder internal combustion engine 1, the exhaust gases of which engine are conducted through six exhaust pipes 2 into an exhaust manifold 3.", "The engine exhaust gases flow from the manifold 3 through an exhaust gas duct 4 toward a turbine 5 of a turbocharger, which turbine drives a compressor 7 through a turbocharger shaft 6.", "The compressor 7 supplies compressed air to each cylinder of the engine 1.", "Charging air compressed by the air compressor 7 passes through a charging air duct 8 and a charging air cooler 9 into an air receiver 10, which air receiver functions as a damping volume.", "The compressed air then flows from the air receiver 10 through two air oscillation pipes 11 into two inlet manifolds 12, each of which manifolds feeds charging air to three cylinders of the engine.", "Each inlet manifold 12 functions as a resonance volume, the purpose of which resonance volume and the purpose of which air oscillation pipes is explained below.", "Compressed air from the air receiver 10 is fed to the engine 1 by two parallel flow systems, each of which systems includes an air oscillation pipe 11 and an inlet manifold 12.", "The periodic suction operation of the engine cylinders produces pressure fluctuations in the suction pipes 13, which suction pipes connect each of the inlet manifolds of each flow system to three engine cylinders.", "These pressure fluctuations propagate from the suction pipes 13 into the inlet manifold 12 and then into the air oscillation pipe 11 of each system.", "It is to be noted that the inlet manifold 12 of each flow system is connected by a bypass duct 14 to the exhaust gas manifold 3 which is arranged on the exhaust side of the engine 1.", "The length of the air oscillation pipe 11 and the bypass duct 14 and the volume of the inlet manifold 12, of each flow system, and of the air receiver 10, are designed so that the natural frequency of the air column in each flow system corresponds to the exciting suction pulsation frequency of the engine in the speed range in which a maximum bypass flow rate is required.", "Resonance therefore occurs in the aforementioned speed range so that the pressure differences across each bypass duct 14 reach a maximum, and therefore the bypass air flow rates reach a maximum value.", "A bypass valve 15, of known construction, and a non-return valve 16, which prevents back flow, are arranged in each bypass duct 14 of each parallel flow system to control and regulate the bypass flow.", "A Borda or re-entrant orifice or some other rectifying element, in which flow in the reverse direction is zero or greatly restricted, can also be used as a non-return valve.", "The aforementioned rectifying element ensures that, when averaged with respect to time, air only flows from the inlet manifold 12 toward and into the exhaust manifold 3.", "Pressures upstream and downstream of each bypass duct 14, an engine or turbocharger speed, and a gas temperature upstream of the turbine can be used as reference variables or controlling variables for actuating the bypass valve 15.", "It is advantageous to provide a charging air cooler, or coolers, between each inlet manifold 12 and the corresponding cylinders fed by the inlet manifold so that the energy of the bypass air stream is not reduced by cooling.", "The pressure of the engine exhaust gases in the exhaust manifold 3 may be regarded as constant by virtue of the relatively large volume of the manifold.", "The pressure difference across each bypass duct 14 can therefore be regarded as depending entirely on the excess of the air pressure in each inlet manifold 12 over the constant gas pressure in the exhaust manifold 3.", "With reference to FIG. 2, a second preferred embodiment of apparatus according to the present invention, which is similar to the first preferred embodiment, utilizes pressure fluctuations of the engine exhaust gases on the exhaust side of the six-cylinder internal combustion engine 1, in addition to charging air pressure fluctuations on the inlet side of the engine 1, for increasing the pressure differences across the bypass ducts 14.", "To obtain the maximum possible pressure differences it is essential that the exhaust gas pressure fluctuations are out of phase with the corresponding charging air pressure fluctuations in the inlet manifolds 12, i.e., that a pressure peak on the inlet side always coincides with a pressure valley on the exhaust side.", "The exhaust pipes 2 of every three adjacently disposed cylinders of the engine 1 merge into exhaust manifolds 17 and 18.", "Each of the two bypass ducts 14, each of which ducts includes a valve 15 and a non-return valve 16, connects one of the two inlet manifolds 12 to a corresponding exhaust manifold 17, 18.", "An injector 19 is provided at each of the places where the bypass ducts 14 merge into their respective manifolds 17, 18.", "These injectors are utilized to increase the total pressure differences across each of the bypass ducts 14, thereby increasing the flow rates of charging air through the bypass ducts 14.", "With reference to FIG. 3, a third preferred embodiment of apparatus, according to the present invention, also includes a six-cylinder internal combustion engine 1, the exhaust gases of which engine are conducted through exhaust pipes 2 to two exhaust manifolds 17 and 18.", "Three cylinders of the engine 1 feed exhaust gases into manifold 17, and three cylinders feed exhaust gases into manifold 18.", "Each of the exhaust manifolds includes an injector 19 and each of the exhaust manifolds conducts engine exhaust gases to a turbocharger.", "The turbocharger of the third preferred embodiment includes a turbine 5 which drives a compressor 7 through a turbocharger shaft 6.", "The compressor 7 feeds compressed air to the engine 1 through a charging air duct 8.", "The charging air duct 8 bifurcates at one point, one fork of the bifurcated duct 8 feeding air through a charging air cooler 9 to a single inlet manifold 12, and the other fork of the bifurcated duct 8 feeding air to a single bypass duct 14.", "The single inlet manifold 12 supplies compressed charging air to each of the cylinders of the six-cylinder engine 1.", "The single bypass duct 14, which includes a valve 15 for regulating the flow of compressed air through the duct 14, feeds compressed air to a bypass air receiver 20 which is arranged on the exhaust side of the engine 1 and which acts as a damping volume.", "The bypass air receiver in turn feeds compressed air to each of two air oscillation pipes 11.", "Each of the pipes 11 includes a non-return valve 16 at the point where each pipe 11 merges into the bypass air receiver 20.", "The pipes 11 each feed compressed air to one of two bypass inlet manifolds 21, each of which bypass inlet manifolds feeds air into one of the exhaust manifolds 17, 18.", "The injectors 19 are located at the points where the bypass inlet manifolds merge into the exhaust manifolds 17, 18.", "In the third preferred embodiment, resonance oscillation of air columns in the air oscillation pipes 11, which oscillation is amplified by the action of the injectors 19 arranged in the two exhaust manifolds 17 and 18, is utilized to increase the flow of air through the bypass duct 14.", "That is, exhaust gas pressure fluctuations, which fluctuations are amplified or reinforced by the action of the injectors 19 in the exhaust manifolds 17 and 18, impart an oscillation to the air columns in the air oscillation pipes 11 and in the bypass inlet manifolds 21.", "The oscillation of the air columns in conjunction with the periodically occurring negative pressures of the exhaust gases emanating from the engine, negative with respect to the bypass air receiver 20, serve to induce bypass air to flow through the non-return valves 16, the air oscillation pipes 11, the bypass inlet manifolds 21, the exhaust manifolds 17 and 18, and into the turbine 5.", "In order for the third embodiment to operate efficiently, the air oscillation pipes 11 and the bypass inlet manifolds 21 must be so arranged that the natural frequency of the air columns therein corresponds to the frequency of the engine exhaust gas surges in the selected range of low load speeds, where high bypass flow rates are needed.", "With reference again to FIG. 3, it should be noted that the non-return valves 16 or equivalent rectifying elements can also be arranged between the bypass inlet manifolds 21 and the exhaust manifolds 17 and 18.", "With reference to FIG. 4, an apparatus which is included in a fourth preferred embodiment of the present invention uses the principle of reflection of periodic pressure waves at an open end of a tube to excite periodic induction waves.", "The apparatus includes an injector 19 arranged at the end of a short exhaust pipe 2, which injector adjoins an open-ended diffuser 22.", "The diffuser 22 extends into an exhaust manifold 3 in which a practically constant gas pressure prevails.", "A non-return valve 16 is arranged within a pipe which connects a bypass air receiver 20 to the injector 19.", "In operation, periodic pressure fluctuations of the exhaust gases emanating from the engine 1 are reinforced by the injector 19.", "Further reinforcement of the periodic pressure fluctuations is effected by reflection of the pressure waves traveling through the diffuser 22 at the open end of the diffuser 22, to produce large periodic pressure differences between the bypass air receiver 20 and the injectors 19.", "The action of the induction waves increases with increasing length of the duct between the injector 19 and the diffuser 22.", "If other means are sufficient to ensure adequate delivery of the bypass air it is possible to dispense with the injector action so that the loss of head of exhaust gases can be minimized.", "With reference again to FIG. 4, it is to be noted that an injector 19 is not essential.", "Rather, it is possible for the confluence of the exhaust pipe 2, emanating from the engine 1, and the bypass duct to be constructed so that the two flows, i.e., the flow of exhaust gases through the exhaust pipe 2 and the bypass flow of compressed air in the bypass duct, are oriented in the same direction in the region where the two flows mix.", "For example, the confluence of the exhaust pipe and the bypass duct may be in the form of a cylindrical exhaust pipe which enters the bypass duct or in the form of two ducts which join at an acute angle in the flow direction.", "With reference to FIG. 5, a modification of the apparatus shown in FIG. 4 includes an air oscillation pipe 11 arranged between the bypass air receiver 20 and the injector 19 so that a reinforced delivery of compressed air is obtained.", "As shown in FIG. 5, the non-return valve 16 may be arranged adjacent the bypass air receiver 20 rather than adjacent the injector 19.", "With reference to FIG. 6, a fourth preferred embodiment of apparatus, according to the present invention, which incorporates the device shown in FIG. 4, includes a six-cylinder internal combustion engine 1.", "Exhaust gases from the engine 1 flow through six exhaust pipes 2 into six injectors 19.", "The exhaust gases flowing through each of the injectors 19 flow, respectively, into six diffusers 22, the ends of which diffusers open into an exhaust manifold 3.", "The exhaust manifold 3 conducts the exhaust gases to a turbine 5 of a turbocharger, which turbine drives a compressor 7 through a turbocharger shaft 6.", "Compressed air supplied by the compressor 7 flows through a duct which feeds compressed air to a charging air duct 8 as well as to a bypass duct 14.", "The compressed air flowing through the charging air duct 8 flows through a charging air cooler 9 and into an inlet manifold, which inlet manifold feeds compressed air to each cylinder of the engine 1.", "The bypass duct 14, which includes a valve 15 for regulating the flow of air through the duct 14, feeds compressed air to a bypass air receiver arranged on the exhaust side of the engine 1.", "Six pipes connect the bypass air receiver to the six diffusers 19 which conduct both engine exhaust gases from the exhaust pipes 2, and compressed air from the bypass air receiver, to the exhaust manifold 3.", "A non-return valve 16 is arranged in each of the six pipes.", "With reference to FIG. 7, a fifth preferred embodiment of apparatus according to the present invention, which incorporates the device shown in FIG. 5, includes a six-cylinder internal combustion engine 1.", "Exhaust gases from the engine 1 flow through six exhaust pipes 2 into six injectors 19.", "The exhaust gases flowing through each of the injectors 19 flow, respectively, into six diffusers 22, the ends of which diffusers open into an exhaust manifold 3.", "The exhaust manifold 3 conducts the exhaust gases to a turbine 5 of a turbocharger, which turbine drives a compressor 7 through a turbocharger shaft 6.", "The compressor 7 feeds compressed air to the engine 1 through a charging air duct 8.", "The charging air duct 8 bifurcates at one point, one fork of the bifurcated duct 8 feeding air through a charging air cooler 9 to a single inlet manifold, and the other fork of the bifurcated duct 8 feeding air to a single bypass duct 14.", "The single inlet manifold supplies compressed charging air to each of the cylinders of the six-cylinder engine 1.", "The bypass duct 14, which includes a valve 15 for regulating the flow of compressed air through the duct 14, feeds compressed air to a bypass air receiver 20, arranged on the exhaust side of the engine 1.", "The bypass air receiver in turn feeds compressed air to each of two air oscillation pipes 11.", "Each of the air oscillation pipes 11 feeds air to one of two bypass inlet manifolds 21, and each of the bypass inlet manifolds 21 is connected by three pipes to three of the six injectors 19.", "Thus, the injectors 19 feed a mixture of exhaust gases from the engine 1 and compressed air from the inlet manifolds 21 into the six diffusers 22, which diffusers feed this mixture into the exhaust manifold 3.", "The exhaust manifold then feeds this mixture to the turbihe 5.", "With reference to FIG. 8, a tower valve 23 may be used as a rectifying element, i.e., as a non-return valve, in the embodiments of the present invention which employ injectors.", "This valve includes a plurality of serially arranged plate valves 24, each of which plate valves has an easily movable, low-inertia valve plate 25.", "An injector nozzle 26 is centrally arranged with the tower valve 23.", "The tower valve 23 is particularly suitable to the present invention because the volume between the end of the injector nozzle 26, where minimum pressure prevails, and the valve plates 25, can be kept very small so that pressure differences are able to act fully and a particularly good delivery effect is obtained.", "The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification.", "The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive.", "Variations and changes may be made by those skilled in the art without departing from the spirit of the present invention." ]
CROSS-REFERENCE TO RELATED APPLICATION(S) [0001] This application relates to and claims priority from U.S. Patent Application No. 61/913,079, filed on Dec. 6, 2013, the entire disclosure of which is incorporated herein by reference. FIELD OF THE DISCLOSURE [0002] The present disclosure relates generally to an exemplary system, method and computer-accessible medium, which can be provided with or can be in cooperation with a pressure sensitive tourniquet arrangement, and which can provide and/or maintain pressure for use in a venipuncture. BACKGROUND INFORMATION [0003] Venipuncture and peripheral intravenous catheter insertion are routine medical procedures performed to collect blood samples, and to administer medications or body fluids. In 2008, there were about 37.5 million hospital admissions in the U.S., and almost every hospital patient can have at least one blood draw on admission. Additionally, 7 out of 10 patients can receive an IV, and 3 out of 10 patients can get an injection of contrast, which can total a minimum of 263 million vein access procedures in the year 2008 alone. This figure does not include any vein access procedures done during an out-patient procedure. Based upon the industry's recognized vein access failure rate of about 40%, which can result in a multiple stick event for 4 out of every 10 patients (e.g., on every stick attempt), this adds up to a minimum estimate of 174 million vein access failures divided between the IV, the blood draw, and the injection of contrast. (See, e.g., The National Phlebotomy website (http://www.nationalphlebotomy.org/). [0004] An extraction of blood from a peripheral vein, or the insertion of catheter, usually benefits from a distention of superficial veins in the arm. For a successful venous distention, the venous flow should be occluded while the arterial flow should unhinder. Ideally, for example, the optimal venous distension can be caused by applying a pressure between the systolic and diastolic pressures. [0005] The current technique for accessing an extremity vein includes placing a tourniquet proximal (e.g., nearer the heart) on the extremity. The tourniquet is most commonly made of an elastic material (e.g. a rubber glove, or a rectangular piece of elastic material), and as such, it can be difficult or even impossible to measure the pressure applied. Therefore, the applied pressure can be above the arterial systolic pressure, which can result in no blood inflow, or the pressure can be below the arterial diastolic pressure, facilitating venous outflow. In both cases, venous distension may not occur. An optimal pressure for the tourniquet would be below the systolic pressure (e.g., the peak arterial pressure), and above the diastolic pressure (e.g., the venous pressure). Applying this pressure can facilitate an arterial inflow, but would likely not facilitate a venous outflow, thereby leading to the distension of the circulation. [0006] The pliable strap or latex strip tourniquet can be commonly used by positioning it around the arm of the patient. Both ends can be grasped and tied to apply a small amount of tension. It can be the least expensive, and is a disposable tourniquet, and it can prevent cross infection of patients, as it does not readily support bacterial growth because of the material property of latex. In addition, it can be easily cleaned with any disinfectant. However, the pliable strap tourniquet cannot be loosened gradually, which can pinch the skin on elderly patients. It also needs nurses and technicians to use both hands for proper positioning. [0007] A Velcro® closure tourniquet can be made of elastic material with a long band that facilitates a wider range of adjustments. Generally, the Velcro® tourniquet can be more expensive than the pliable strap tourniquet. It can be easily cleaned with any disinfectant. In addition, the Velcro® tourniquet can be easier to apply and release than the pliable strap tourniquet. The Velcro strap, however, cannot be loosened gradually, and it also likely needs using both hands for proper positioning. [0008] The buckle closure tourniquet can be made of cloth fabric with a buckle closure (e.g., seat-belt design). It can be gradually loosened and tightened again, if necessary. Unlike the tourniquets above, it may not be disposable, and cannot be easily cleaned with disinfectants. Generally, the buckle closure tourniquet is not commonly used because of its high cost and restricted usage. [0009] A common blood pressure cuff can be used as a tourniquet. The cuff can be inflated to a pressure between the systolic and diastolic pressures for venous distension. It can be useful among patients with weak veins that can be difficult to see with the naked eyes. Blood pressure cuffs usually include a sphygmomanometer, thus, the applied pressure can be readily known. [0010] In the surgical setting, surgical tourniquets can be applied to the limb occlusion pressure (“LOP”), the minimum pressure used to occlude a patient's limb completely, to localize anesthesia drugs and to provide a bloodless operating field during surgeries. There are many different surgical tourniquet systems. A surgical tourniquet can consist of an instrument for pressure regulation, and an inflatable cuff for pressure application. It can be designed to measure the LOP using the ascending LOP measurement technique. The ascending LOP measurement can determine the LOP by slowly increasing pressure in the cuff until the LOP can be reached. [0011] This surgical tourniquet generally requires the surgical staffs to enter an estimated LOP value. This LOP value can be set as the reference pressure, and can be regulated by a controller during surgeries every 40 millisecond with the allowed deviation of ±15 mmHg. A pulse oximeter can be utilized as a means to adjust the preset reference pressure. The pulse oximeter can be composed of an infrared LED with wavelength of about 915 nm, and a photodiode that can be sensitive to that wavelength. The basic principle of pulse measuring can be based on the absorption of infrared light by oxygenated hemoglobin. Based on oxygenated hemoglobin concentration, current can be produced by the photodiode. This current can be filtered, sampled and analyzed by the controller. However, concentration of oxygenated hemoglobin in the extremity can be time-varying, in synchrony with the cardiac cycle. As a result, time-varying current signifies incomplete occlusion of arterial flow. The preset reference pressure can be adjusted according to the pulse detection in the extremity. A new reference pressure can be obtained when no time-varying current can be detected. This pressure will be the LOP and it will be maintained until the end of surgeries. The A.T.S. 3000 Automatic Tourniquet System is a medical tourniquet system with a processor controlling two air pressure ports at each cuff. One port can be used for pressure measurement, while the other port regulates cuff pressure. It uses a LOP sensor at the patient's index finger or toe to provide a recommended LOP to the surgeon. However, this pressure can be used to completely occlude the patient's limb. [0012] Thus, it may be beneficial to provide an exemplary pressure sensitive device that can reduce the rate of vein access failure for an individual patient's blood pressure, and which can overcome at least some of the deficiencies described herein above. SUMMARY OF EXEMPLARY EMBODIMENTS [0013] These and other objects of the present disclosure can be achieved by provision of an exemplary apparatus that can include a pressure applying first arrangement, a pressure regulating second arrangement configured to control a pressure applied by the first arrangement, a pulse detecting third arrangement, and a hardware fourth arrangement configured control the second arrangement based on information or a signal(s) provided from the third arrangement. The second arrangement can include an air pump(s) and a solenoid valve(s). The solenoid valve(s) can be a normally open solenoid valve. [0014] In some exemplary embodiments of the present disclosure, the third arrangement can include a pulse sensor(s), which can include an infrared emitter(s) and an infrared detector(s). The one pulse sensor(s) can also include an auscultatory arrangement(s). A light-emitting diode arrangement(s) can be configured to provide feedback from the pressure sensitive tourniquet, which can include information regarding an error with the apparatus or that the apparatus is currently being operated. The first arrangement can include an inflatable cuff. [0015] These and other objects of the present disclosure can be achieved by provision of systems, methods and computer-accessible mediums that can, for example, receive information related to a detection of a pulse of a patient(s), and increase a pressure using a hardware arrangement to reach a first pressure level corresponding to the pulse no longer being detected. The pressure can be decreased to reach a second pressure level corresponding to the pulse being again detected, and the pressure can be maintained at the second pressure level to facilitate a venipuncture of the patient(s). The first pressure level can correspond to an arterial systolic pressure of the patient(s), and the second pressure level can correspond to a pressure that can be less than the arterial systolic pressure and greater than an arterial diastolic pressure. The information can be generated using a pulse detecting arrangement, which can be a pulse sensor or an auscultatory arrangement. The hardware arrangement can include an air pump(s) and a solenoid valve(s). [0016] These and other objects, features and advantages of the exemplary embodiments of the present disclosure will become apparent upon reading the following detailed description of the exemplary embodiments of the present disclosure, when taken in conjunction with the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS [0017] Further objects, features and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying Figures showing illustrative embodiments of the present disclosure, in which: [0018] FIG. 1 is a photograph of exemplary components for the exemplary device according to an exemplary embodiment of the present disclosure; [0019] FIG. 2 is a photograph of an exemplary lighting apparatus according to an exemplary embodiment of the present disclosure; [0020] FIG. 3 is a photograph of an exemplary emergency release valve according to an exemplary embodiment of the present disclosure; [0021] FIG. 4 is an exemplary flow diagram of a process according to an exemplary embodiment of the present disclosure; [0022] FIG. 5 is a circuit diagram of an exemplary device according to an exemplary embodiment of the present disclosure; [0023] FIG. 6 is a schematic diagram of an exemplary light-emitting diode incorporated into the exemplary device according to an exemplary embodiment of the present disclosure; [0024] FIG. 7 is an schematic diagram of a pinout of an NPN transistor according to an exemplary embodiment of the present disclosure; [0025] FIG. 8 is a schematic diagram of an exemplary circuit used in the exemplary device according to an exemplary embodiment of the present disclosure; [0026] FIG. 9 is an illustration of an exemplary magnetic field produced by an exemplary solenoid used in the exemplary device according to an exemplary embodiment of the present disclosure; [0027] FIG. 10 is an exemplary circuit diagram illustrating current produced by the exemplary device according to an exemplary embodiment of the present disclosure; [0028] FIG. 11 is an exemplary circuit diagram illustrating current redirection by the exemplary device according to an exemplary embodiment of the present disclosure; [0029] FIG. 12 is an exemplary graph illustrating an estimated volumetric flow rate curve of an exemplary pump according to an exemplary embodiment of the present disclosure; [0030] FIG. 13 is an exemplary illustration of the conservation of mass in a control volume; [0031] FIG. 14A is an exemplary diagram illustrating a laminar flow of a Newtonian fluid through a cylinder; [0032] FIG. 14B is an exemplary diagram illustrating a momentum balance on a differential volume; [0033] FIG. 15 is an exemplary block diagram of an exemplary system according exemplary embodiment of the present disclosure; [0034] FIG. 16 is a top view photograph of an exemplary circuit board according to an exemplary embodiment of the present disclosure; [0035] FIGS. 17A and 17B are front and top rear photographs, respectively, of the exemplary circuit board of FIG. 16 provided with an enclosure, forming an exemplary system according to an exemplary embodiment of the present disclosure; [0036] FIG. 18 is a photograph of an assembly of a blood pressure cuff that can be used with the exemplary system shown in FIGS. 16, 17A and 17B according to an exemplary embodiment of the present disclosure; [0037] FIG. 19 is an exemplary schematic diagram of the exemplary circuit board illustrated in FIG. 16 according to an exemplary embodiment of the present disclosure, and [0038] FIGS. 20A-20H are schematic diagrams of various view of sections of the layout of the exemplary printed circuit board of FIG. 16 . [0039] Throughout the drawings, the same reference numerals and characters, unless otherwise stated, are used to denote like features, elements, components or portions of the illustrated embodiments. Moreover, while the present disclosure will now be described in detail with reference to the figures, it is done so in connection with the illustrative embodiments and is not limited by the particular embodiments illustrated in the figures and the appended claims. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS [0040] The “systolic” blood pressure is the peak arterial pressure occurring during contraction of the left ventricle of the heart. The “diastolic” blood pressure is the minimum arterial pressure which occurs during relaxation and dilatation of the ventricles of the heart as the ventricles fill with blood. The arterial diastolic pressure can approximate the pressure found in the venous circulation. The exemplary device can facilitate the optimization of tourniquet pressure between arterial systolic and diastolic pressures. The exemplary tourniquet (e.g., blood pressure cuff) can be placed on the extremity and a pulse detecting arrangement can be placed distal to the cuff. The cuff can be inflated until the pulse oximeter signal can be lost, indicating that the cuff can be inflated to the arterial systolic pressure. The cuff can be deflated until the pulse oximeter signal can be present, and then the cuff pressure can be held at this point, which can be between the arterial systolic and the diastolic pressures. This can lead to progressive and rapid venous distension, which can facilitate a superior venipuncture. [0041] The exemplary device/apparatus can be designed and/or sized for different patient types (e.g., adult, pediatric, geriatric patients and/or obese patients), and can include an inflatable cuff 105 (e.g., a blood pressure cuff) in order to apply pressure at a patient's limb where venous distention can be created by blocking venous flow, and can facilitate arterial flow. The inflatable cuff can be an adult-sized standard blood pressure cuff. [0042] As shown in FIG. 1 , the exemplary device can include a pressure regulating unit/device/apparatus/system/arrangement, which can comprise a digital or analog circuit, as well as an air pump 110 (e.g., a miniature air pump) and a solenoid valve 115 (e.g., a normally open solenoid valve) and can be controlled by a microcontroller unit 120 (“MCU”) (e.g., an Arduino controller), in order to maintain the pressure applied by the cuff 105 , by determining the pressure through pressure gauge. The pressure regulating unit/device/apparatus/system/arrangement can increase, decrease or maintain the pressure at the cuff 105 by operating the solenoid valve 115 and the air pump 110 . The normally-open solenoid valve 115 can be and/or include an electromagnetic component that can close the airway when electrified. The exemplary valve 115 can be used to control the release of air from the cuff 105 (e.g., deflation). The one-way valve can be, and/or can include, a mechanical component that, for example, may only facilitate the inflow of air to the cuff 105 . Both the air pump 110 and the one-way valve 115 can control the inflation of the cuff 105 . Table 1 below summarizes an exemplary pressure regulation by the solenoid valve and the air pump. [0000] TABLE 1 Cuff Pressure Regulation by the Solenoid Valve and the Air Pump Pressure Regulation Solenoid Valve Air Pump Increase Pressure Close On Decrease Pressure Open Off Maintain Pressure Close Off [0043] The exemplary pressure regulating unit/device/apparatus/system/arrangement can include a pulse detecting unit/apparatus 130 (e.g., an infrared emitter and detector), which can detect the patient's pulse and, can provide feedback to the pressure regulating unit. The pulse detecting unit/apparatus can be coupled to an operational amplifier (e.g., op amp 145 ) for processing the signal. The exemplary pressure regulating unit/device/apparatus/system/arrangement can automatically determine, apply, and/or maintain pressure between the systolic and diastolic blood pressure in order to cause venous distention (e.g., by blocking venous flow while facilitating arterial flow). The exemplary cuff 105 can be easily encircled around, and detached from, the patient's limb in order to shorten the procedure duration for each venipuncture. The exemplary pressure regulating unit/device/apparatus/system/arrangement can also include an emergency pressure release mechanism 135 (e.g., a pressure release valve) in order to avoid injury to the patient. (See, e.g., FIG. 3 ). Additionally, the exemplary pressure regulating unit/device/apparatus/system/arrangement can include a pressure release valve which can automatically release pressure above a predetermined amount. The applied pressure can be determined using an exemplary pressure sensor, which can initiate the release of the pressure through the pressure release valve when the predetermined amount of pressure is achieved or exceeded. [0044] The exemplary air pump and solenoid valve can be powered by power source 140 (e.g., a battery, such as a 9V), and can be turned on and off by switch 150 . A lighting apparatus 155 (e.g., light-emitting diodes (“LEDs”)) can be included to indicate the operational status of the exemplary pressure regulating unit/device/apparatus/system/arrangement [0045] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be lightweight (e.g., less than about 10 pounds), and can be small (e.g., 20 cm×15 cm×10 cm excluding the exemplary pulse detecting unit and the exemplary cuff). The exemplary pressure regulating unit/device/apparatus/system/arrangement can be inflatable at a rate of approximately 10-50 mmHg/sec, and can deflate at a rate of approximately 2-10 mmHg/sec. [0046] The exemplary pulse detecting unit can include a pulse sensor (e.g., a pulse oximeter). When the pulse sensor detects blood flow, the cuff pressure can be increased above the systolic pressure, which can occlude both arterial and venous flows. The cuff pressure can be decreased to, and maintained at, a point between the systolic and diastolic pressures, where the resumption of blood flow can be detected. [0047] The exemplary pulse detecting unit can include an auscultatory apparatus (e.g., a sound sensor). A sound sensor can be used to detect the Korotkoff sounds produced when the cuff pressure can be between the systolic and diastolic pressure by applying gradual increases in the cuff pressure. The cuff pressure can be maintained as soon as the first Korotkoff sound can be detected. The exemplary pulse detecting unit can include an oscillometric apparatus, and can apply the mean arterial pressure (“MAP”). A pressure of about 200 mmHg can be applied, which can be decreased gradually until oscillations of the artery can be detected by the pressure sensor. The pressure with the highest oscillation amplitude can be equivalent to the MAP. The pulse detecting unit can also include an indwelling arterial line. [0048] As shown in FIG. 2 , the lighting apparatus 155 can indicate the operational status of the exemplary pressure regulating unit/device/apparatus/system/arrangement. For example, three LEDs (e.g., orange, green and red) can be mounted on a top face of the exemplary pressure regulating unit/device/apparatus/system/arrangement. One or more LEDs (e.g., the orange) can signify that the device can be in operation. Another one or more LEDs (e.g., the green) can signify a successful operation of the device and thus, venipuncture can be performed. Further one or more LEDs (e.g., the red) can signify errors in device operation. [0049] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be operated by wrapping the exemplary cuff 105 around the upper arm of a patient that can be near the desired site of the venipuncture. The exemplary cuff can be tightened such that about 1-2 fingers can be inserted into the space between the patient's arm and the exemplary cuff. The exemplary sensor (e.g., pulse oximeter) can be placed on the thumb of the patient corresponding to the arm the exemplary cuff is placed on. The exemplary pressure regulating unit/device/apparatus/system/arrangement can be started and/or operated automatically. [0050] FIG. 4 shows an exemplary flow diagram of a method for using the exemplary pressure regulating unit/device/apparatus/system/arrangement according to an exemplary embodiment of the present disclosure. For example, at procedure 410 , an infrared emitter can emit a signal in a fingertip 405 and detect a signal from fingertip 405 . At procedure 415 , exemplary filters and amplifiers can receive the raw signal from the infrared emitter and detector and process the signal. At procedure 420 , the initial peak-to-peak signal difference and threshold can be determined, and at procedure 425 , a new peak-to-peak signal difference can be determined and compared to a threshold. If the blood flow can be greater than the threshold, on a first detection by the infrared emitter and detector, the pump and valve can be turned on at procedure 440 and the pressure can be increased at procedure 445 . If the blood flow can be greater than the threshold, and it is the first detection by the infrared emitter and detector, then at procedure 450 , the pump can be turned off, the valve can remain on and the pressure can be maintained at procedure 455 to initiate a venipuncture at procedure 460 . If the blood flow can be less than the threshold at procedure 425 , then the pump and valve can be turned off at procedure 430 , and the pressure can be decreased at procedure 435 until the blood flow can be greater than the threshold. [0051] FIG. 5 shows an exemplary circuit diagram of the exemplary pressure regulating unit/device/apparatus/system/arrangement according to an exemplary embodiment of the present disclosure. For example, the air pump and the solenoid valve can be connected to an inflatable cuff. The resistances of the resistors and the capacitances of the capacitors are shown in Table 2. Exemplary part numbers of different components are shown in Table 3. [0000] TABLE 2 Resistors Resistances (Ω) Capacitors Capacitance (μF) R1, R5, & R6 680 C1 & C3 1 R2 180 C2 & C4 0.1 R3 & R4 360 — — R7 150 — — R8 33000 — — R9 & R12 68000 — — R10 & R13 6800 — — R11 & R14 680000 — — [0000] TABLE 3 Components Part Numbers Infrared Emitter and Detector 276-142 Air Pump KPM14A-3A2 Solenoid Valve KSV05A Inflatable Cuff 143401 Green 4 mm LED (LED 1) 276-271 Red 4 mm LED (LED 2) 276-270A Orange 4 mm LED (LED 3) 276-270B Transistor T1 2N3904 Transistor T2 MPS2222A Diodes D1-D2 1N4003 Switch 275-695 Arduino Mini 05 A000087 Operational Amplifier U1 LM324N Exemplary Photoplethysmogram Signal Analysis [0052] The exemplary pressure regulating unit/device/apparatus/system/arrangement can use a reflective photoplethysmogram (“PPG”) sensor for pulse determination. The exemplary PPG sensor can detect the level of hemoglobin, which can be converted to current. Beer-Lambert's Law, absorbance and illuminance can be the principle equations used by the PPG sensor, which states that the absorbance of light can increase linearly with the concentration of the absorbing substance and the distance of the source of light. Thus, for example: [0000] A=abc   (1) [0000] which can indicate the parameters in the Beer-Lambert's Law, where A can be absorbance, a can be the molar extinction coefficient, b can be the path length, and c can be concentration. [0053] For the exemplary PPG sensor, the exemplary path length can be constant, and can be equal to the depth of the fingertip the sensor is attached to. The absorbance can vary in relation to the concentration of the hemoglobin as the molar extinction coefficient of hemoglobin can also be a constant. Even though whole blood does not strictly follow the law (see, e.g., Reference 1), Beer-Lambert's Law can generally be valid when applied to hemoglobin at the fingertip, since red blood cells can pass one at a time through the capillary. [0054] Absorbance can be calculated using the following exemplary equation: [0000] A = log 10  I incident I transmitted ( 2 ) [0000] where I transmitted can be the luminous intensity of the transmitted light and I incident can be the luminous intensity of the incident light. [0055] Since the exemplary PPG sensor can be used to measure the reflected light, and the fingertip can be sealed, it can be assumed that lights can either be reflected or absorbed, thus, equation 2 can take the form of, for example: [0000] A = log 10  I incident I reflected ( 3 ) [0000] where I reflected can be the luminous intensity of the reflected light. [0056] The exemplary PPG sensor can use a photodiode to produce current based on the reflected light. The current can be produced according to the following exemplary equation: [0000] I=RE v   (4) [0000] where I can be the current, R can be the responsitivity of the photodiode, and E v can be the illuminance of the light. The illuminance E v in Equation 4 can be related to the luminous intensity by the following exemplary equation: [0000] E v = ∅ v A  I v  Ω A ( 5 ) [0000] where φ v can be luminous flux defined as I v Ω, Ωcan be a solid angle, which can be a two-dimensional angle that can have a magnitude as the area of a piece of a unit sphere (see, e.g., Reference 2), and A can be the area the light shines to. By combining Equations 4 and 5, the output current of the photodiode can be obtained as a function of luminous intensity of the reflected light, which can be, for example: [0000] I = R   Ω A  I reflected ( 6 ) Exemplary Hemoglobin Concentration—Output Current Relation [0057] Equation 1 relates concentration to absorbance, Equation 3 relates absorbance to luminous intensity and Equation 6 relates luminous intensity to current. By combining these three equations, the current can be obtained as a function of concentration, which can be, for example: [0000] I = R   Ω   I incident A  10 - abc ( 7 ) [0058] In Equation 7, R and I incident can be the intrinsic properties of the infrared detector and emitter. A and Ω can approximately be the projected area and the surface area of the emitter. The constants a and b can depend on the thickness of the fingertip, and absorbance of hemoglobin at the wavelength of the emitter. The hemoglobin concentration, c, can be a variable depending on blood flow of the subject. Thus, the output current of the exemplary PPG sensor can vary with the hemoglobin concentration at the fingertip. When blood flow can be occluded, hemoglobin concentration c can remain constant, so a constant current can be obtained. By differentiating a time-varying current from constant current, occlusion of blood vessels can be determined. Exemplary Circuit Analysis [0059] Exemplary circuit analyses can be performed using Ohm's Law on the three exemplary LEDs, the exemplary air pump and the exemplary solenoid valve. Ohm's Law relates current and resistance to voltage, as shown in the following exemplary equation: [0000] V=IR   (8) [0000] where V can be voltage, I can be current, and R can be resistance. Exemplary LED Currents [0060] Three LEDs can be used in the exemplary device/apparatus for indication purposes. An exemplary LED circuit is shown in FIG. 6 . In this exemplary circuit, the LED 605 can be connected in series with a resistor 610 . The power can be supplied to the circuit by the Arduino's output, which can be a constant 5 V signal 615 . Since the LED and the resistor can be in series, the current in the two components can be the same. When illuminated, there can be a voltage drop across the LED. This voltage drop can be approximately 2 V. Thus, the voltage across the resistor can be the Arduino's output subtracted by 2 V. Using Ohm's Law and the resistances for R 1 , R 5 , and R 6 (e.g., Table 2), the currents I 1 , I 2 , and I 3 in LED 1 , LED 2 , and LED 3 , respectively can be obtained as, for example: [0000] I 1 = I 2 = I 3 = ( 5 - 2 )  V R   1 = ( 5 - 2 )  V R   5 = ( 5 - 2 )  V R   6 = 3   V 680  Ω ≈ 0.00441   A = mA [0000] The exemplary maximum current the LED can operate safely can be about 20 mA. (See, e.g., Reference 3). As the values of I 1 , I 2 , and I 3 can be lower than the maximum current, it can be concluded that the LED's are working safely. Exemplary Transistors [0061] Two or more NPN transistors can be used. NPN transistors can have three pins, collector 705 (“C”), base 710 (“B”), and emitter 715 (“E”), as shown in FIG. 7 . Current can flow from C to E depending on the input of B. For a NPN transistor, the current that flows into C (I c ) can be the amplified version of the current that flows into B (I b ). The DC current gain, h FE , can be defined as the ratio of I c over I b (See, e.g., Reference 4). The h FE can signify a linear relationship between the input current I b and output current I c . [0062] The transistors in the exemplary pressure regulating unit/device/apparatus/system/arrangement can be used to control the air pump and the solenoid valve, as both components can utilize a large amount of current that cannot be obtained from the Arduino alone. The exemplary transistors can be configured as switches that can control the air pump and the solenoid valve based on I b . Switching transistors may need saturation, as only two states—“on” and “off” can exist for saturated transistors. (See, e.g., Reference 6). Saturation in a transistor can usually be done by inputting large I b such that I c becomes independent of the gain. Thus, I c can remain constant as long as I b may not be zero (e.g., On), and I c can become zero when I b can be zero (e.g., Off). The transistor can be saturated when I b can be approximately of [0000] 1 10  I c . [0063] The exemplary air pump and solenoid valve can be powered by a 9V battery 805 , and can be connected according to the transistor circuit shown in FIG. 8 . The operating currents of the air pump and the solenoid valve can be about 380 mA and about 75 mA, respectively, when the power supply can be capable for outputting these currents. (See, e.g., References 7 and 8). Thus, by modeling the air pump and solenoid valve as load resistors 810 , the corresponding I c values of the air pump and solenoid valve can be equal to the operating currents. The current I b can then be determined and can consequently be R b . Exemplary Air Pump and Solenoid Valve [0064] To saturate transistors T 1 and T 2 , I b can be chosen as about 28 mA and about 7 mA, for the air pump and the solenoid valve, respectively. Using Ohm's Law (e.g., Equation 8), the resistances of the resistors connecting to pin B (R b ) can be determined as, for example: [0000] R b = 5   V 0.028   A ≈ 180   Ω   ( Air   Pump ) R b = 5   V 0.007   A ≈ 720   Ω   ( Solenoid   Valve ) [0000] Thus, an approximately 180Ω resistor (e.g., R 2 ) can be connected to pin B of transistor T 2 for the air pump (see e.g., Table 2 and FIG. 5 ). An approximately 720Ω resistance can be achieved by connecting two approximately 360Ω resistors (e.g., R 3 & R 4 ) in series for the solenoid valve. (i.d.). Induced Voltage Estimation [0065] The air pump and the solenoid valve can be electromechanical components that contain solenoids (e.g., coils). Solenoids can induce electromotive force (“EMF”), or voltage, when magnetic flux through the solenoid changes with time. This is known as Faraday's Law. Faraday's Law can be shown in the following exemplary formula (see, e.g., Reference 9): [0000] ɛ = - N   ∅ B  t ( 9 ) [0000] where ε can be the induced voltage EMF, N can be the number of loops, [0000]  ∅ B  t [0000] can be the derivative of magnetic flux (φ B ) with respect to time (t). [0066] Magnetic flux in Equation 9 can be defined as the surface integral of the dot product of magnetic field, and the normal vector to an area where magnetic field lines pass through. (See, e.g., FIG. 9 ). Magnetic flux can be calculated using exemplary Equation 10. (See, e.g., Reference 10). [0000] φ B = {right arrow over (B)}·d{right arrow over (A)}=AB cos(θ)   (10) [0000] where {right arrow over (B)} can be magnetic field with magnitude B, {right arrow over (A)} can be the normal vector of the area magnetic field lines pass through with area A, and θ can be the smallest angle between the two vectors. [0067] As shown in FIG. 9 , the solenoid can produce magnetic fields based on the current. The Magnetic field produced by the solenoid can be calculated using Equation 11 (see, e.g., Reference 11), where, for example: [0000] B = μ 0  N l  I ( 11 ) [0000] where μ O can be the permeability of free space, l can be the length of the solenoid, and I can be the current in the solenoid. [0068] Since the magnetic field produced inside of the solenoid can be parallel to the normal vector of the cross-sectional area of the solenoid (see, e.g., FIG. 5 ), the surface integral and dot product in Equation 10 can be simplified to exemplary Equation 12 (cos(0°)=1). [0000] φ B =BA   (12) [0000] Combining Equations 9, 11 and 12, an expression for induced voltage due to the change of current in the solenoid can be obtained as, for example: [0000] ɛ = - A   μ 0  N 2 l   l  t ( 13 ) [0000] Equation 13 can relate the change of current to the voltage induced by the solenoid. The term [0000] A   μ 0  N 2 l [0000] can be known as the inductance of the solenoid. According to this formula, when the air pump and the solenoid valve can be turned off, the current can suddenly decrease to zero. A sudden decrease in current [0000] (  l  t < 0 ) [0000] can induce a positive EMF (ε) with respect to the ground as shown in FIG. 10 . These exemplary induced voltages, together with the 9V battery, can produce large currents toward the transistors, can enter the ground pin of the Arduino, and can damage the two components. FIG. 11 illustrates an exemplary circuit diagram of the exemplary current redirection by the exemplary pressure regulating unit/device/apparatus/system/arrangement. Exemplary Protective Diode [0069] One solution to avoid the potential damage of the prototype due to the induced voltages can be to connect a diode parallel to the exemplary solenoid (see, e.g., Reference 13) (e.g., air pump and solenoid valve) as shown in FIG. 7 . The diodes (e.g., D 1 and D 2 shown in FIG. 5 ) connected across the solenoid valve and the air pump can be termed protective diodes and can complete the short circuits that redirect the induced currents back to the solenoids, thus preventing damage to the rests of the circuitry. Exemplary Air Pump Flow Rate and Applied Pressure Estimation [0070] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be used to apply pressure to the patient's arm through inflation of the inflatable cuff by air. By assuming air as an ideal gas, the cuff pressure can be predicted using the ideal gas law, which can be, for example: [0000] PV=nRT   (14) [0000] where P can be the absolute pressure, V can be the volume, n can be the number of molecules, R can be the gas constant, and T can be the absolute temperature. [0071] While encircling a patient's arm, the inflatable cuff can only hold a specific volume. When this volume can be reached, the number of molecules can increase due to the input of air by the pump while the volume remains unchanged. If the air pump's volumetric flow rate can be Q, the gauge pressure of the inflatable cuff, P, can be calculated using the following exemplary formula derived from the ideal gas law: [0000] P = RT  ( ρ + Q   ρ   t V ) + P L - P atm ( 15 ) [0000] where ρ can be the density of air, [0000] n v , [0000] Q can be the volumetric flow rate, P L can be the load pressure, and P atm can be the atmospheric pressure. [0072] The term Qρt in Equation 15 can be the number of molecules pumped into the inflatable cuff in time t due to volumetric flow rate of Q (e.g., Qρ can be molar flow rate of air). P L can be the load pressure defined as the pressure that the air pump operates against. It can also be that the pressure remains in the cuff due to the previous pumping. Because the pressure in the ideal gas law can be the absolute pressure, atmospheric pressure P atm can be subtracted to obtain the applied pressure, which can be a gauge pressure. Since air can be assumed to be an ideal gas, the term RTρ can be the same as atmospheric pressure, and the two terms can cancel out. Equation 15 can then be simplified to, for example: [0000] P = RT   ρ V  ( Qt ) + P L ( 16 ) [0073] If the volumetric flow rate Q of the air pump can be known, the applied pressure can be calculated or otherwise determined using Equation 16. However, the volumetric flow rate can be a function of load pressure P L . Exemplary Air Volumetric Flow Rate [0074] The exemplary air pump can have a volumetric flow rate curve under the zero-load current of 155 mA. (See, e.g., Reference 8). This curve can follow a typical exponential decay and can be approximated by the following exemplary equation: [0000] Q= 1.33·10 −5 ·e −0.0046 P L   (17) [0075] In the exemplary device, the zero-load current can be about 380 mA. If it can further be assumed that the volumetric flow rate curve can maintain its shape, but the magnitude can change linearly with the zero-load current, the volumetric flow rate for 380 mA can be obtained as, for example: [0000] Q= 3.27·10 −5 ·e −0.0046P L   (18) [0000] Equation 18 is plotted in FIG. 12 . When the load pressure, or pressure that exists inside the cuff due to previous pumpings increases, the volumetric flow rate can decrease. Exemplary Applied Pressure Estimation [0076] By substituting Equations 18 into Equation 16, the applied pressure as a function of the load pressure, or the pressure existing in the cuff, can be obtained as, for example: [0000] P = 3.27 * 10 - 5 * RT   ρ   t V   - 0.0046  P L + P L ( 19 ) [0000] Because of the stepwise application of pressure in the exemplary device, Equation 19 can be used to estimate the newly applied pressure to the arm using the existing pressure in the cuff (P L ). Exemplary Blood Flow Modeling [0077] Blood flow through arteries and veins can be determined by utilizing the conservation of mass principle, which states that the rate of accumulation of mass in a control volume can equal the difference between the flows of mass into and the mass out of the control volume, as shown in FIG. 13 . Exemplary Poiseuille Flow [0078] The flow of blood can be assumed to be a pressure-driven laminar flow of an incompressible Newtonian fluid (e.g., blood) through a cylindrical tube (e.g., blood vessel). Such a case can be known as the Poiseuille flow. [0079] The flow can be unidirectional along the longitudinal axis. When it can be fully developed, the velocity of blood can be a function of radius only, and can be expected to exhibit maximum velocity with a radial symmetry about the centerline. The velocity profile under these assumptions is shown in FIGS. 14A , which illustrates laminar flow of a Newtonian fluid through a cylinder, and 14 B, which illustrates a momentum balance on a differential volume. [0080] Since the flow can be steady, the sum of all forces can be equal to zero, and the only relevant forces can be pressures and shear stresses. Under these assumptions, the Navier-Stokes Equation in the z-direction (e.g., exemplary Equation 20) can be simplified to exemplary Equation 21. [0000] ρ  ( ∂ V z ∂ t + V r  ∂ V z ∂ r + V 0 r  ∂ V z ∂ θ + V z  ∂ V z ∂ z ) = -  P  Z + μ  [ 1 r    r  ( r   V z  r ) + 1 r 2  ∂ 2  V z ∂ θ 2 + ∂ 2  V z ∂ z 2 ] + ρ   g z ( 20 )  0 = -  p  z + μ r    r  ( r   V z  r ) ( 21 ) [0000] where P can be pressure, z can be the longitudinal direction, μ can be viscosity, r can be the radial direction, and V z can be the velocity in the z-direction. [0081] In Equation 21, pressure P can be a function of z, and velocity V z can be a function of r. The only situation where the sum of the derivatives of a function of z and a function of r can be zero is when they both can be constants. By integrating the pressure gradient as a constant with boundary conditions (“BC”), the following, for example, can be obtained: [0000] P (0)= P O and P ( L )= P L   (BC: Pressure) [0000] and the pressure distribution can be obtained as, for example: [0000] P  ( z ) = P o - P L L  z + P o ( 22 ) [0000] where P O can be the pressure at the origin (e.g., the heart), L can be the distance from the origin, and P L can be the pressure at a distance L (e.g., the extremity). [0082] By taking the derivative of Equation 22 with respect to z, and substituting the expression into Equation 21, the differential equation of V z can be obtained as, for example: [0000] P o - P L L = μ r    r  ( r   V z  r ) ( 23 ) [0000] The general solution to Equation 23 can be, for example: [0000] V z  ( r ) = ( P o - P L )  r 2 4  Lu + C 1   ln  ( r ) + C 2 ( 24 ) [0000] where C 1 and C 2 can be constants of integration. [0083] By using the following boundary conditions, the velocity profile V z can be obtained as, for example: [0000] V z  ( R ) = 0   and    V z  r  ( 0 ) = 0 ( BC  :   Velocity ) [0000] and, for example: [0000] V z  ( r ) = ( P 0 - P L )  R 2 4  L   μ  ( r 2 R 2 - 1 ) ( 25 ) Exemplary Blood Volumetric Flow Rate [0084] The volumetric flow rate of blood Q B (e.g., Equation 27 below) can be obtained by integrating the velocity over the cross-sectional area of the blood vessel. Thus, for example [0000] Q B = ∫ 0 R  V z  ( r )  2  π   r   r ( 26 ) Q B = ( P o  P L )  π   R 4 8  L   μ ( 27 ) [0085] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be used to apply pressure between the systolic and diastolic pressures. The brachial artery and the cephalic vein are the two main blood vessels in the upper arm that can receive the applied pressure. The diameter of the brachial artery can be approximately 3.52 mm, (see, e.g., Reference 16), and the diameter of the cephalic vein can be about 2.4 mm. (See, e.g., Reference 17). The cephalic vein can be assumed to be occluded when the applied pressure can be higher than the diastolic pressure. The brachial artery can be assumed be occluded if the applied pressure can be higher than the systolic pressure. The radii can be described using the following exemplary equations for the brachial artery and the cephalic vein, respectively, by assuming the radii decrease linearly when the applied pressure can be increased: [0000] R A = { 0.00176 - 0.00176 SP  P , 0 ≤ P ≤ SP 0 , P > SP ( 28 ) [0000] and, for example: [0000] R V = { 0.0012 - 0.0012 DP  P , 0 ≤ P ≤ DP 0 , P > DP ( 29 ) [0086] The radii can be redefined to zero when the applied pressure can be greater than the systolic pressure, and the diastolic pressure for the brachial artery and the cephalic vein, respectively, since negative radii can be physically impossible. [0087] The flow rate in Equation 27 can assume blood to be a Newtonian fluid. However, blood's behavior can depend on shear rate (e.g., velocity gradient). A more sophisticate model of blood flow can be shown as, for example: [0000] Q B = π   R 4  Δ   P 8  η N  L  [ 1 + 11 21  ( τ 0 τ w ) 4 - 16 7  ( τ 0 τ w ) + 8 3  ( τ 0 τ w ) ] ( 30 ) [0000] (see, e.g., Reference 18) where R can be radius of the blood vessel, P can be pressure, η N can be blood viscosity at high shear rate, L can be the length of the blood vessel, τ O can be yield stress of blood, and τ W can be shear stress at the wall of the blood vessel. Exemplary Hoop Stress Analysis Exemplary Hoop Stress [0088] The inflatable cuff can be wrapped around the upper arm to apply a pressure. The pressure the exemplary device/apparatus can apply can be approximately 220 mmHg depending on different individuals. In the presence of an exerted pressure, the walls of blood vessels can contract. Therefore, the blood vessels can resist the contraction force with a hoop stress in the circumferential direction to avoid any vessel damage. The hoop stress can have vital physiological significance. It can be the primary force in regulating blood vessel wall thickness and residue stress, in response to blood pressure and hypertension. (See, e.g., Reference 19). Assuming that the blood vessels can be very thin, the hoop stress can be calculated using, for example: [0000] σ θ = Pr t ( 31 ) [0000] (see, e.g., Reference 20) where τ θ can be the hoop stress, P can be pressure, r can be radius, and t can be thickness. Exemplary Hoop Stress Calculation [0089] The exemplary dimensions for the brachial artery and the cephalic vein are summarized in Table 4 below. The hoop stresses can be calculated using Equation 31 at a maximum pressure of about 220 mmHg The hoop stresses calculated from previous experimental studies are included in the table as references to determine the accuracy of the exemplary calculation. [0000] TABLE 4 Dimensions of the Blood Vessels, Calculated Hoop Stresses and Reference Hoop Stresses. Brachial Artery Cephalic Vein Thickness (t) 0.35 mm 1.35 mm Diameter (2r) 3.52 mm 2.40 mm Radius/Thickness 5.03 0.89 (r/t) Calculated 147.5 kPa 26.1 kPa Hoop Stress Reference Hoop 100 kPa- 245 kPa Stress 280 kPa Exemplary Blood Vessel Damage Analysis [0090] One of the purposes of the hoop stress analysis can be to ensure that the maximum applied pressure of about 220 mmHg does not cause any damage to blood vessels. According to one study, most human arteries' can yield hoop stresses which can be in the order of 10 5 Pa (e.g., 100 kPa). (See, e.g., Reference 19). In another study, most mammalian arteries can be expected to exert hoop stress between about 240 kPa and about 280 kPa at about 100 mmHg. (See, e.g., Reference 23). In the exemplary analysis, the brachial artery can exert about 147.5 kPa at the maximum pressure of about 220 mmHg. Since 147.5 kPa can be in the order of about 10 5 Pa and much less than about 240 kPa, the exemplary device does not cause any damage to the brachial artery. Similarly, the cephalic vein can be found to exert a hoop stress of about 245 kPa at the mean arterial pressure under normal physiological conditions. (See, e.g., Reference 22). In the exemplary analysis, the hoop stress for cephalic vein can be calculated to be about 26.1 kPa at the maximum pressure of about 220 mmHg. Since 26.1 kPa can be much less than about 245 kPa, the pressure exerted from the exemplary device will not damage the cephalic vein. [0091] FIG. 15 shows a block diagram of an exemplary embodiment of a system according to the present disclosure. For example, exemplary procedures in accordance with the present disclosure described herein can be performed by a processing arrangement and/or a computing arrangement 1502 . Such processing/computing arrangement 1502 can be, for example, entirely or a part of, or include, but not limited to, a computer/processor 1504 that can include, for example, one or more microprocessors, and use instructions stored on a computer-accessible medium (e.g., RAM, ROM, hard drive, or other storage device). [0092] As shown in FIG. 15 , for example, a computer-accessible medium 1506 (e.g., as described herein above, a storage device such as a hard disk, floppy disk, memory stick, CD-ROM, RAM, ROM, etc., or a collection thereof) can be provided (e.g., in communication with the processing arrangement 1502 ). The computer-accessible medium 1506 can contain executable instructions 1508 thereon. In addition or alternatively, a storage arrangement 1510 can be provided separately from the computer-accessible medium 1506 , which can provide the instructions to the processing arrangement 1502 so as to configure the processing arrangement to execute certain exemplary procedures, processes and methods, as described herein above, for example. [0093] Further, the exemplary processing arrangement 1502 can be provided with or include an input/output arrangement 1514 , which can include, for example, a wired network, a wireless network, the Internet, an intranet, a data collection probe, a sensor, etc. As shown in FIG. 15 , the exemplary processing arrangement 1502 can be in communication with an exemplary display arrangement 1512 , which, according to certain exemplary embodiments of the present disclosure, can be a touch-screen configured for inputting information to the processing arrangement in addition to outputting information from the processing arrangement, for example. Further, the exemplary display 1512 and/or a storage arrangement 1510 can be used to display and/or store data in a user-accessible format and/or user-readable format. [0094] According to further exemplary embodiments of the present disclosure, it can be possible to provide certain exemplary changes to the system according to the exemplary embodiment of the present disclosure. For example, it can be possible to utilize a standard 9V alkaline battery, although a use of a 9V lithium battery can provide an extended capacity (e.g., which can be as much as 3 times) greater than a 9V alkaline battery. In addition, for example, it can be possible to provide a configuration which can effectuate a reverse battery protection. A further exemplary solenoid valve can be provided which can have a higher voltage capacity, and which can lower power consumption. Further, instead of or together with the external release valve, it can be possible to utilize an integral release valve. [0095] In additional exemplary embodiments of the present disclosure, another exemplary circuit board can be provided for the use with the exemplary system according to the present disclosure. For example, as shown in FIG. 16 , such exemplary circuit board can be laid out for a top mounted power switch and LED indicators, and can be placed in a SERPAC enclosure, as shown in FIGS. 17A and 17B (providing top front and top rear views thereof). Holes can be machined to provide access to the internal works. Nomenclature can be silkscreened onto the enclosure. A 9V battery compartment on the rear of the exemplary enclosure provides for battery replacement without disassembly. [0096] Thus, according to such exemplary embodiment of the present disclosure, as illustrated in FIG. 18 , a standard blood pressure cuff 1805 can be used with the exemplary system 1810 shown in FIGS. 16, 17A and 17B . For example, the pump bulb can be removed, and the release valve and cuff can be attached using Luer connectors. The pressure gauge can be attached to the cuff. The finger sensor can be replaced by a Nelcor compatible SpO 2 adult finger unit and attached to the PST via, for example, a standard 9 pin serial port connector or using other known connectors. [0097] FIG. 19 shows an exemplary schematic diagram of the exemplary circuit board illustrated in FIG. 16 , and FIGS. 20A-20H shows various view of sections of the layout of the exemplary printed circuit. [0098] The foregoing merely illustrates the principles of the disclosure. Various modifications and alterations to the described embodiments will be apparent to those skilled in the art in view of the teachings herein. It will thus be appreciated that those skilled in the art will be able to devise numerous systems, arrangements, and procedures which, although not explicitly shown or described herein, embody the principles of the disclosure and can be thus within the spirit and scope of the disclosure. Various different exemplary embodiments can be used together with one another, as well as interchangeably therewith, as should be understood by those having ordinary skill in the art. In addition, certain terms used in the present disclosure, including the specification, drawings and claims thereof, can be used synonymously in certain instances, including, but not limited to, for example, data and information. It should be understood that, while these words, and/or other words that can be synonymous to one another, can be used synonymously herein, that there can be instances when such words can be intended to not be used synonymously. Further, to the extent that the prior art knowledge has not been explicitly incorporated by reference herein above, it is explicitly incorporated herein in its entirety. All publications referenced are incorporated herein by reference in their entireties. EXEMPLARY REFERENCES [0099] The following references are hereby incorporated by reference in their entirety. [1] Steinke J M. Role of Light Scattering in Whole Blood Oximetry. IEEE Transactions on Biomedical Engineering. 1986; 33:294-301. [2] Solid Angle—from Wolfram Math World. http://mathworld.wolfram.com/SolidAngle.html. Accessed Mar. 3, 2013. [3] 4 mm Red/Orange/Green LEDs with Holders, RadioShack. http://www.radioshack.com/product/index.jsp?productId=2062568, http://www.radioshack.com/product/index.jsp?productId=2062570, and http://www.radioshack.com/product/index.jsp?productId=2062569. Accessed May 18, 2013. [4] Bhandari N. A Simple Relationship between the Transistor Parameters hFE and hfe. Proceedings of the IEEE. 1967; 55:1099. [5] NPN Transistor. http://i.stack.imgur.com/m9rv6.png. Accessed Feb. 24, 2013. [6] Anderson A E. Transistors in Switching Circuits. Proceedings of the IRE. 1952; 40:1541-1558. [7] KSV05A Solenoid Valve Data Sheet. http://www.koge.com/UploadFile/pdf/2011325142159-KSV05A.pdf. Accessed Feb. 24, 2013. [8] KPM14A Air Pump Data Sheet. http://www.koge.com/UploadFile/pdf/2011324115349-KPM14A.pdf. Accessed Feb. 24, 2013. [9] Serway R A and Jewett J W. Physics for Scientists and Engineers with Modern Physics. 7 th ed. Thomson Learning. Belmont, 2008, pp 869. [10] Serway R A and Jewett J W. Physics for Scientists and Engineers with Modern Physics. 7 th ed. Thomson Learning. Belmont, 2008, pp 850. [11] Serway R A and Jewett J W. Physics for Scientists and Engineers with Modern Physics. 7 th ed. Thomson Learning. Belmont, 2008, pp 849. [12] Magnetic Field Surrounding Solenoid. http://www.rfcafe.com/references/electrical/Electricians%20Mate%203%20-%20Navy%20Training%20Courses%20%20NAVPERS%2010548/images/magnetic-field-surrounding-solenoid.jpg. Accessed Feb. 24, 2013. [13] Pilliner G W. Protection and Safety. Part 6: Electromagnetic Problems. Electronic Systems News. 1988; 1988: 19-20. [14] Tuskey G A, Yuan F, Katz D F. Transport Phenomena in Biological Systems. 2 nd ed. Pearson Education . Upper Saddle River, 2009, pp 63. [15] Tuskey G A, Yuan F, Katz D F. Transport Phenomena in Biological Systems. 2 nd ed. Pearson Education. Upper Saddle River, 2009, pp 93. [16] Holubkov R, Karas R H, Pepine C J, Rickens C R, Reichek N, Rogers W J, Sharaf B L, Sopko G, Merz C N, Kelsey S F, McGorray S P, and Reis S E. Large Brachial Artery Diameter is Associated with Angiographic Coronary Artery Disease in Women. Am Heart J. 2002; 143:802-807. [17] Spivack D E, Kelly P, Gaughan J P, and van Bemmelen P S. Mapping of Superficial Extremity Veins: Normal Diameters and Trends in a Vascular Patient-Population. Ultrasound Med Biol. 2012; 38:190-194. [18] Tuskey G A, Yuan F, Katz D F. Transport Phenomena in Biological Systems. 2 nd ed. Pearson Education. Upper Saddle River, 2009, pp 109. [19] Ku D N. Blood Flow in Arteries. Annual Review of Fluid Mechanics. 1997; 29:399-434. [20] Ethier C R and Simmons C A. Introductory Biomechanics: From Cells to Organisms. 1 st ed. Cambridge University Press. Cambridge, 2007. pp 190. [21] Weidinger F, Frick M, Alber H F, Ulmar H, Chwarzacher S P, and Pachinger O. Association of Wall Thickness of the Brachial Measured with High-Resolution Ultrasound with Risk Factors and Coronary Artery Disease. Am J Cardiol. 2002; 89:1025-1029. [22] Jaberi A, Muradali D, Marticorena R M, Dacouris N, Boutin A, Mulligan A M, Ballyk P D, Prabhudesai V, Campbell V M, and Donnelly S M. Arteriovenous Fistulas for Hemodialysis: Application of High-Frequency US to Assess Vein Wall Morphology for Cannulation Readiness. Radiology. 2011; 261:616-624. [23] Tracy R E and Eigenbrodt M L. Coronary Artery Circumferential Stress: Departure from Laplace Expectations with Aging. Scientific World Journal. 2009; 9:946-960. [24] Arduino Mini. http://arduino.cc/en/uploads/Main/Mini05_front.jpg. Accessed May 18, 2013. [25] Arduino Mini and NG Breadboard. http://arduino.cc/en/uploads/Guide/ArduinoMiniAndNGBreadboardPhoto.jpg. Accessed May 18, 2013.
Exemplary systems, methods and computer-accessible mediums can be provided that can, for example, receive information related to a detection of a pulse of a patient(s), and increase a pressure using a hardware arrangement to reach a first pressure level corresponding to the pulse no longer being detected. The pressure can be decreased to reach a second pressure level corresponding to the pulse being again detected, and the pressure can be maintained at the second pressure level to facilitate a venipuncture of the patient(s).
Briefly describe the main idea outlined in the provided context.
[ "CROSS-REFERENCE TO RELATED APPLICATION(S) [0001] This application relates to and claims priority from U.S. Patent Application No. 61/913,079, filed on Dec. 6, 2013, the entire disclosure of which is incorporated herein by reference.", "FIELD OF THE DISCLOSURE [0002] The present disclosure relates generally to an exemplary system, method and computer-accessible medium, which can be provided with or can be in cooperation with a pressure sensitive tourniquet arrangement, and which can provide and/or maintain pressure for use in a venipuncture.", "BACKGROUND INFORMATION [0003] Venipuncture and peripheral intravenous catheter insertion are routine medical procedures performed to collect blood samples, and to administer medications or body fluids.", "In 2008, there were about 37.5 million hospital admissions in the U.S., and almost every hospital patient can have at least one blood draw on admission.", "Additionally, 7 out of 10 patients can receive an IV, and 3 out of 10 patients can get an injection of contrast, which can total a minimum of 263 million vein access procedures in the year 2008 alone.", "This figure does not include any vein access procedures done during an out-patient procedure.", "Based upon the industry's recognized vein access failure rate of about 40%, which can result in a multiple stick event for 4 out of every 10 patients (e.g., on every stick attempt), this adds up to a minimum estimate of 174 million vein access failures divided between the IV, the blood draw, and the injection of contrast.", "(See, e.g., The National Phlebotomy website (http://www.", "nationalphlebotomy.org/).", "[0004] An extraction of blood from a peripheral vein, or the insertion of catheter, usually benefits from a distention of superficial veins in the arm.", "For a successful venous distention, the venous flow should be occluded while the arterial flow should unhinder.", "Ideally, for example, the optimal venous distension can be caused by applying a pressure between the systolic and diastolic pressures.", "[0005] The current technique for accessing an extremity vein includes placing a tourniquet proximal (e.g., nearer the heart) on the extremity.", "The tourniquet is most commonly made of an elastic material (e.g. a rubber glove, or a rectangular piece of elastic material), and as such, it can be difficult or even impossible to measure the pressure applied.", "Therefore, the applied pressure can be above the arterial systolic pressure, which can result in no blood inflow, or the pressure can be below the arterial diastolic pressure, facilitating venous outflow.", "In both cases, venous distension may not occur.", "An optimal pressure for the tourniquet would be below the systolic pressure (e.g., the peak arterial pressure), and above the diastolic pressure (e.g., the venous pressure).", "Applying this pressure can facilitate an arterial inflow, but would likely not facilitate a venous outflow, thereby leading to the distension of the circulation.", "[0006] The pliable strap or latex strip tourniquet can be commonly used by positioning it around the arm of the patient.", "Both ends can be grasped and tied to apply a small amount of tension.", "It can be the least expensive, and is a disposable tourniquet, and it can prevent cross infection of patients, as it does not readily support bacterial growth because of the material property of latex.", "In addition, it can be easily cleaned with any disinfectant.", "However, the pliable strap tourniquet cannot be loosened gradually, which can pinch the skin on elderly patients.", "It also needs nurses and technicians to use both hands for proper positioning.", "[0007] A Velcro® closure tourniquet can be made of elastic material with a long band that facilitates a wider range of adjustments.", "Generally, the Velcro® tourniquet can be more expensive than the pliable strap tourniquet.", "It can be easily cleaned with any disinfectant.", "In addition, the Velcro® tourniquet can be easier to apply and release than the pliable strap tourniquet.", "The Velcro strap, however, cannot be loosened gradually, and it also likely needs using both hands for proper positioning.", "[0008] The buckle closure tourniquet can be made of cloth fabric with a buckle closure (e.g., seat-belt design).", "It can be gradually loosened and tightened again, if necessary.", "Unlike the tourniquets above, it may not be disposable, and cannot be easily cleaned with disinfectants.", "Generally, the buckle closure tourniquet is not commonly used because of its high cost and restricted usage.", "[0009] A common blood pressure cuff can be used as a tourniquet.", "The cuff can be inflated to a pressure between the systolic and diastolic pressures for venous distension.", "It can be useful among patients with weak veins that can be difficult to see with the naked eyes.", "Blood pressure cuffs usually include a sphygmomanometer, thus, the applied pressure can be readily known.", "[0010] In the surgical setting, surgical tourniquets can be applied to the limb occlusion pressure (“LOP”), the minimum pressure used to occlude a patient's limb completely, to localize anesthesia drugs and to provide a bloodless operating field during surgeries.", "There are many different surgical tourniquet systems.", "A surgical tourniquet can consist of an instrument for pressure regulation, and an inflatable cuff for pressure application.", "It can be designed to measure the LOP using the ascending LOP measurement technique.", "The ascending LOP measurement can determine the LOP by slowly increasing pressure in the cuff until the LOP can be reached.", "[0011] This surgical tourniquet generally requires the surgical staffs to enter an estimated LOP value.", "This LOP value can be set as the reference pressure, and can be regulated by a controller during surgeries every 40 millisecond with the allowed deviation of ±15 mmHg.", "A pulse oximeter can be utilized as a means to adjust the preset reference pressure.", "The pulse oximeter can be composed of an infrared LED with wavelength of about 915 nm, and a photodiode that can be sensitive to that wavelength.", "The basic principle of pulse measuring can be based on the absorption of infrared light by oxygenated hemoglobin.", "Based on oxygenated hemoglobin concentration, current can be produced by the photodiode.", "This current can be filtered, sampled and analyzed by the controller.", "However, concentration of oxygenated hemoglobin in the extremity can be time-varying, in synchrony with the cardiac cycle.", "As a result, time-varying current signifies incomplete occlusion of arterial flow.", "The preset reference pressure can be adjusted according to the pulse detection in the extremity.", "A new reference pressure can be obtained when no time-varying current can be detected.", "This pressure will be the LOP and it will be maintained until the end of surgeries.", "The A.T.S. 3000 Automatic Tourniquet System is a medical tourniquet system with a processor controlling two air pressure ports at each cuff.", "One port can be used for pressure measurement, while the other port regulates cuff pressure.", "It uses a LOP sensor at the patient's index finger or toe to provide a recommended LOP to the surgeon.", "However, this pressure can be used to completely occlude the patient's limb.", "[0012] Thus, it may be beneficial to provide an exemplary pressure sensitive device that can reduce the rate of vein access failure for an individual patient's blood pressure, and which can overcome at least some of the deficiencies described herein above.", "SUMMARY OF EXEMPLARY EMBODIMENTS [0013] These and other objects of the present disclosure can be achieved by provision of an exemplary apparatus that can include a pressure applying first arrangement, a pressure regulating second arrangement configured to control a pressure applied by the first arrangement, a pulse detecting third arrangement, and a hardware fourth arrangement configured control the second arrangement based on information or a signal(s) provided from the third arrangement.", "The second arrangement can include an air pump(s) and a solenoid valve(s).", "The solenoid valve(s) can be a normally open solenoid valve.", "[0014] In some exemplary embodiments of the present disclosure, the third arrangement can include a pulse sensor(s), which can include an infrared emitter(s) and an infrared detector(s).", "The one pulse sensor(s) can also include an auscultatory arrangement(s).", "A light-emitting diode arrangement(s) can be configured to provide feedback from the pressure sensitive tourniquet, which can include information regarding an error with the apparatus or that the apparatus is currently being operated.", "The first arrangement can include an inflatable cuff.", "[0015] These and other objects of the present disclosure can be achieved by provision of systems, methods and computer-accessible mediums that can, for example, receive information related to a detection of a pulse of a patient(s), and increase a pressure using a hardware arrangement to reach a first pressure level corresponding to the pulse no longer being detected.", "The pressure can be decreased to reach a second pressure level corresponding to the pulse being again detected, and the pressure can be maintained at the second pressure level to facilitate a venipuncture of the patient(s).", "The first pressure level can correspond to an arterial systolic pressure of the patient(s), and the second pressure level can correspond to a pressure that can be less than the arterial systolic pressure and greater than an arterial diastolic pressure.", "The information can be generated using a pulse detecting arrangement, which can be a pulse sensor or an auscultatory arrangement.", "The hardware arrangement can include an air pump(s) and a solenoid valve(s).", "[0016] These and other objects, features and advantages of the exemplary embodiments of the present disclosure will become apparent upon reading the following detailed description of the exemplary embodiments of the present disclosure, when taken in conjunction with the appended claims.", "BRIEF DESCRIPTION OF THE DRAWINGS [0017] Further objects, features and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying Figures showing illustrative embodiments of the present disclosure, in which: [0018] FIG. 1 is a photograph of exemplary components for the exemplary device according to an exemplary embodiment of the present disclosure;", "[0019] FIG. 2 is a photograph of an exemplary lighting apparatus according to an exemplary embodiment of the present disclosure;", "[0020] FIG. 3 is a photograph of an exemplary emergency release valve according to an exemplary embodiment of the present disclosure;", "[0021] FIG. 4 is an exemplary flow diagram of a process according to an exemplary embodiment of the present disclosure;", "[0022] FIG. 5 is a circuit diagram of an exemplary device according to an exemplary embodiment of the present disclosure;", "[0023] FIG. 6 is a schematic diagram of an exemplary light-emitting diode incorporated into the exemplary device according to an exemplary embodiment of the present disclosure;", "[0024] FIG. 7 is an schematic diagram of a pinout of an NPN transistor according to an exemplary embodiment of the present disclosure;", "[0025] FIG. 8 is a schematic diagram of an exemplary circuit used in the exemplary device according to an exemplary embodiment of the present disclosure;", "[0026] FIG. 9 is an illustration of an exemplary magnetic field produced by an exemplary solenoid used in the exemplary device according to an exemplary embodiment of the present disclosure;", "[0027] FIG. 10 is an exemplary circuit diagram illustrating current produced by the exemplary device according to an exemplary embodiment of the present disclosure;", "[0028] FIG. 11 is an exemplary circuit diagram illustrating current redirection by the exemplary device according to an exemplary embodiment of the present disclosure;", "[0029] FIG. 12 is an exemplary graph illustrating an estimated volumetric flow rate curve of an exemplary pump according to an exemplary embodiment of the present disclosure;", "[0030] FIG. 13 is an exemplary illustration of the conservation of mass in a control volume;", "[0031] FIG. 14A is an exemplary diagram illustrating a laminar flow of a Newtonian fluid through a cylinder;", "[0032] FIG. 14B is an exemplary diagram illustrating a momentum balance on a differential volume;", "[0033] FIG. 15 is an exemplary block diagram of an exemplary system according exemplary embodiment of the present disclosure;", "[0034] FIG. 16 is a top view photograph of an exemplary circuit board according to an exemplary embodiment of the present disclosure;", "[0035] FIGS. 17A and 17B are front and top rear photographs, respectively, of the exemplary circuit board of FIG. 16 provided with an enclosure, forming an exemplary system according to an exemplary embodiment of the present disclosure;", "[0036] FIG. 18 is a photograph of an assembly of a blood pressure cuff that can be used with the exemplary system shown in FIGS. 16, 17A and 17B according to an exemplary embodiment of the present disclosure;", "[0037] FIG. 19 is an exemplary schematic diagram of the exemplary circuit board illustrated in FIG. 16 according to an exemplary embodiment of the present disclosure, and [0038] FIGS. 20A-20H are schematic diagrams of various view of sections of the layout of the exemplary printed circuit board of FIG. 16 .", "[0039] Throughout the drawings, the same reference numerals and characters, unless otherwise stated, are used to denote like features, elements, components or portions of the illustrated embodiments.", "Moreover, while the present disclosure will now be described in detail with reference to the figures, it is done so in connection with the illustrative embodiments and is not limited by the particular embodiments illustrated in the figures and the appended claims.", "DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS [0040] The “systolic”", "blood pressure is the peak arterial pressure occurring during contraction of the left ventricle of the heart.", "The “diastolic”", "blood pressure is the minimum arterial pressure which occurs during relaxation and dilatation of the ventricles of the heart as the ventricles fill with blood.", "The arterial diastolic pressure can approximate the pressure found in the venous circulation.", "The exemplary device can facilitate the optimization of tourniquet pressure between arterial systolic and diastolic pressures.", "The exemplary tourniquet (e.g., blood pressure cuff) can be placed on the extremity and a pulse detecting arrangement can be placed distal to the cuff.", "The cuff can be inflated until the pulse oximeter signal can be lost, indicating that the cuff can be inflated to the arterial systolic pressure.", "The cuff can be deflated until the pulse oximeter signal can be present, and then the cuff pressure can be held at this point, which can be between the arterial systolic and the diastolic pressures.", "This can lead to progressive and rapid venous distension, which can facilitate a superior venipuncture.", "[0041] The exemplary device/apparatus can be designed and/or sized for different patient types (e.g., adult, pediatric, geriatric patients and/or obese patients), and can include an inflatable cuff 105 (e.g., a blood pressure cuff) in order to apply pressure at a patient's limb where venous distention can be created by blocking venous flow, and can facilitate arterial flow.", "The inflatable cuff can be an adult-sized standard blood pressure cuff.", "[0042] As shown in FIG. 1 , the exemplary device can include a pressure regulating unit/device/apparatus/system/arrangement, which can comprise a digital or analog circuit, as well as an air pump 110 (e.g., a miniature air pump) and a solenoid valve 115 (e.g., a normally open solenoid valve) and can be controlled by a microcontroller unit 120 (“MCU”) (e.g., an Arduino controller), in order to maintain the pressure applied by the cuff 105 , by determining the pressure through pressure gauge.", "The pressure regulating unit/device/apparatus/system/arrangement can increase, decrease or maintain the pressure at the cuff 105 by operating the solenoid valve 115 and the air pump 110 .", "The normally-open solenoid valve 115 can be and/or include an electromagnetic component that can close the airway when electrified.", "The exemplary valve 115 can be used to control the release of air from the cuff 105 (e.g., deflation).", "The one-way valve can be, and/or can include, a mechanical component that, for example, may only facilitate the inflow of air to the cuff 105 .", "Both the air pump 110 and the one-way valve 115 can control the inflation of the cuff 105 .", "Table 1 below summarizes an exemplary pressure regulation by the solenoid valve and the air pump.", "[0000] TABLE 1 Cuff Pressure Regulation by the Solenoid Valve and the Air Pump Pressure Regulation Solenoid Valve Air Pump Increase Pressure Close On Decrease Pressure Open Off Maintain Pressure Close Off [0043] The exemplary pressure regulating unit/device/apparatus/system/arrangement can include a pulse detecting unit/apparatus 130 (e.g., an infrared emitter and detector), which can detect the patient's pulse and, can provide feedback to the pressure regulating unit.", "The pulse detecting unit/apparatus can be coupled to an operational amplifier (e.g., op amp 145 ) for processing the signal.", "The exemplary pressure regulating unit/device/apparatus/system/arrangement can automatically determine, apply, and/or maintain pressure between the systolic and diastolic blood pressure in order to cause venous distention (e.g., by blocking venous flow while facilitating arterial flow).", "The exemplary cuff 105 can be easily encircled around, and detached from, the patient's limb in order to shorten the procedure duration for each venipuncture.", "The exemplary pressure regulating unit/device/apparatus/system/arrangement can also include an emergency pressure release mechanism 135 (e.g., a pressure release valve) in order to avoid injury to the patient.", "(See, e.g., FIG. 3 ).", "Additionally, the exemplary pressure regulating unit/device/apparatus/system/arrangement can include a pressure release valve which can automatically release pressure above a predetermined amount.", "The applied pressure can be determined using an exemplary pressure sensor, which can initiate the release of the pressure through the pressure release valve when the predetermined amount of pressure is achieved or exceeded.", "[0044] The exemplary air pump and solenoid valve can be powered by power source 140 (e.g., a battery, such as a 9V), and can be turned on and off by switch 150 .", "A lighting apparatus 155 (e.g., light-emitting diodes (“LEDs”)) can be included to indicate the operational status of the exemplary pressure regulating unit/device/apparatus/system/arrangement [0045] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be lightweight (e.g., less than about 10 pounds), and can be small (e.g., 20 cm×15 cm×10 cm excluding the exemplary pulse detecting unit and the exemplary cuff).", "The exemplary pressure regulating unit/device/apparatus/system/arrangement can be inflatable at a rate of approximately 10-50 mmHg/sec, and can deflate at a rate of approximately 2-10 mmHg/sec.", "[0046] The exemplary pulse detecting unit can include a pulse sensor (e.g., a pulse oximeter).", "When the pulse sensor detects blood flow, the cuff pressure can be increased above the systolic pressure, which can occlude both arterial and venous flows.", "The cuff pressure can be decreased to, and maintained at, a point between the systolic and diastolic pressures, where the resumption of blood flow can be detected.", "[0047] The exemplary pulse detecting unit can include an auscultatory apparatus (e.g., a sound sensor).", "A sound sensor can be used to detect the Korotkoff sounds produced when the cuff pressure can be between the systolic and diastolic pressure by applying gradual increases in the cuff pressure.", "The cuff pressure can be maintained as soon as the first Korotkoff sound can be detected.", "The exemplary pulse detecting unit can include an oscillometric apparatus, and can apply the mean arterial pressure (“MAP”).", "A pressure of about 200 mmHg can be applied, which can be decreased gradually until oscillations of the artery can be detected by the pressure sensor.", "The pressure with the highest oscillation amplitude can be equivalent to the MAP.", "The pulse detecting unit can also include an indwelling arterial line.", "[0048] As shown in FIG. 2 , the lighting apparatus 155 can indicate the operational status of the exemplary pressure regulating unit/device/apparatus/system/arrangement.", "For example, three LEDs (e.g., orange, green and red) can be mounted on a top face of the exemplary pressure regulating unit/device/apparatus/system/arrangement.", "One or more LEDs (e.g., the orange) can signify that the device can be in operation.", "Another one or more LEDs (e.g., the green) can signify a successful operation of the device and thus, venipuncture can be performed.", "Further one or more LEDs (e.g., the red) can signify errors in device operation.", "[0049] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be operated by wrapping the exemplary cuff 105 around the upper arm of a patient that can be near the desired site of the venipuncture.", "The exemplary cuff can be tightened such that about 1-2 fingers can be inserted into the space between the patient's arm and the exemplary cuff.", "The exemplary sensor (e.g., pulse oximeter) can be placed on the thumb of the patient corresponding to the arm the exemplary cuff is placed on.", "The exemplary pressure regulating unit/device/apparatus/system/arrangement can be started and/or operated automatically.", "[0050] FIG. 4 shows an exemplary flow diagram of a method for using the exemplary pressure regulating unit/device/apparatus/system/arrangement according to an exemplary embodiment of the present disclosure.", "For example, at procedure 410 , an infrared emitter can emit a signal in a fingertip 405 and detect a signal from fingertip 405 .", "At procedure 415 , exemplary filters and amplifiers can receive the raw signal from the infrared emitter and detector and process the signal.", "At procedure 420 , the initial peak-to-peak signal difference and threshold can be determined, and at procedure 425 , a new peak-to-peak signal difference can be determined and compared to a threshold.", "If the blood flow can be greater than the threshold, on a first detection by the infrared emitter and detector, the pump and valve can be turned on at procedure 440 and the pressure can be increased at procedure 445 .", "If the blood flow can be greater than the threshold, and it is the first detection by the infrared emitter and detector, then at procedure 450 , the pump can be turned off, the valve can remain on and the pressure can be maintained at procedure 455 to initiate a venipuncture at procedure 460 .", "If the blood flow can be less than the threshold at procedure 425 , then the pump and valve can be turned off at procedure 430 , and the pressure can be decreased at procedure 435 until the blood flow can be greater than the threshold.", "[0051] FIG. 5 shows an exemplary circuit diagram of the exemplary pressure regulating unit/device/apparatus/system/arrangement according to an exemplary embodiment of the present disclosure.", "For example, the air pump and the solenoid valve can be connected to an inflatable cuff.", "The resistances of the resistors and the capacitances of the capacitors are shown in Table 2.", "Exemplary part numbers of different components are shown in Table 3.", "[0000] TABLE 2 Resistors Resistances (Ω) Capacitors Capacitance (μF) R1, R5, &", "R6 680 C1 &", "C3 1 R2 180 C2 &", "C4 0.1 R3 &", "R4 360 — — R7 150 — — R8 33000 — — R9 &", "R12 68000 — — R10 &", "R13 6800 — — R11 &", "R14 680000 — — [0000] TABLE 3 Components Part Numbers Infrared Emitter and Detector 276-142 Air Pump KPM14A-3A2 Solenoid Valve KSV05A Inflatable Cuff 143401 Green 4 mm LED (LED 1) 276-271 Red 4 mm LED (LED 2) 276-270A Orange 4 mm LED (LED 3) 276-270B Transistor T1 2N3904 Transistor T2 MPS2222A Diodes D1-D2 1N4003 Switch 275-695 Arduino Mini 05 A000087 Operational Amplifier U1 LM324N Exemplary Photoplethysmogram Signal Analysis [0052] The exemplary pressure regulating unit/device/apparatus/system/arrangement can use a reflective photoplethysmogram (“PPG”) sensor for pulse determination.", "The exemplary PPG sensor can detect the level of hemoglobin, which can be converted to current.", "Beer-Lambert's Law, absorbance and illuminance can be the principle equations used by the PPG sensor, which states that the absorbance of light can increase linearly with the concentration of the absorbing substance and the distance of the source of light.", "Thus, for example: [0000] A=abc (1) [0000] which can indicate the parameters in the Beer-Lambert's Law, where A can be absorbance, a can be the molar extinction coefficient, b can be the path length, and c can be concentration.", "[0053] For the exemplary PPG sensor, the exemplary path length can be constant, and can be equal to the depth of the fingertip the sensor is attached to.", "The absorbance can vary in relation to the concentration of the hemoglobin as the molar extinction coefficient of hemoglobin can also be a constant.", "Even though whole blood does not strictly follow the law (see, e.g., Reference 1), Beer-Lambert's Law can generally be valid when applied to hemoglobin at the fingertip, since red blood cells can pass one at a time through the capillary.", "[0054] Absorbance can be calculated using the following exemplary equation: [0000] A = log 10  I incident I transmitted ( 2 ) [0000] where I transmitted can be the luminous intensity of the transmitted light and I incident can be the luminous intensity of the incident light.", "[0055] Since the exemplary PPG sensor can be used to measure the reflected light, and the fingertip can be sealed, it can be assumed that lights can either be reflected or absorbed, thus, equation 2 can take the form of, for example: [0000] A = log 10  I incident I reflected ( 3 ) [0000] where I reflected can be the luminous intensity of the reflected light.", "[0056] The exemplary PPG sensor can use a photodiode to produce current based on the reflected light.", "The current can be produced according to the following exemplary equation: [0000] I=RE v (4) [0000] where I can be the current, R can be the responsitivity of the photodiode, and E v can be the illuminance of the light.", "The illuminance E v in Equation 4 can be related to the luminous intensity by the following exemplary equation: [0000] E v = ∅ v A  I v  Ω A ( 5 ) [0000] where φ v can be luminous flux defined as I v Ω, Ωcan be a solid angle, which can be a two-dimensional angle that can have a magnitude as the area of a piece of a unit sphere (see, e.g., Reference 2), and A can be the area the light shines to.", "By combining Equations 4 and 5, the output current of the photodiode can be obtained as a function of luminous intensity of the reflected light, which can be, for example: [0000] I = R   Ω A  I reflected ( 6 ) Exemplary Hemoglobin Concentration—Output Current Relation [0057] Equation 1 relates concentration to absorbance, Equation 3 relates absorbance to luminous intensity and Equation 6 relates luminous intensity to current.", "By combining these three equations, the current can be obtained as a function of concentration, which can be, for example: [0000] I = R   Ω   I incident A  10 - abc ( 7 ) [0058] In Equation 7, R and I incident can be the intrinsic properties of the infrared detector and emitter.", "A and Ω can approximately be the projected area and the surface area of the emitter.", "The constants a and b can depend on the thickness of the fingertip, and absorbance of hemoglobin at the wavelength of the emitter.", "The hemoglobin concentration, c, can be a variable depending on blood flow of the subject.", "Thus, the output current of the exemplary PPG sensor can vary with the hemoglobin concentration at the fingertip.", "When blood flow can be occluded, hemoglobin concentration c can remain constant, so a constant current can be obtained.", "By differentiating a time-varying current from constant current, occlusion of blood vessels can be determined.", "Exemplary Circuit Analysis [0059] Exemplary circuit analyses can be performed using Ohm's Law on the three exemplary LEDs, the exemplary air pump and the exemplary solenoid valve.", "Ohm's Law relates current and resistance to voltage, as shown in the following exemplary equation: [0000] V=IR (8) [0000] where V can be voltage, I can be current, and R can be resistance.", "Exemplary LED Currents [0060] Three LEDs can be used in the exemplary device/apparatus for indication purposes.", "An exemplary LED circuit is shown in FIG. 6 .", "In this exemplary circuit, the LED 605 can be connected in series with a resistor 610 .", "The power can be supplied to the circuit by the Arduino's output, which can be a constant 5 V signal 615 .", "Since the LED and the resistor can be in series, the current in the two components can be the same.", "When illuminated, there can be a voltage drop across the LED.", "This voltage drop can be approximately 2 V. Thus, the voltage across the resistor can be the Arduino's output subtracted by 2 V. Using Ohm's Law and the resistances for R 1 , R 5 , and R 6 (e.g., Table 2), the currents I 1 , I 2 , and I 3 in LED 1 , LED 2 , and LED 3 , respectively can be obtained as, for example: [0000] I 1 = I 2 = I 3 = ( 5 - 2 )  V R   1 = ( 5 - 2 )  V R   5 = ( 5 - 2 )  V R   6 = 3   V 680  Ω ≈ 0.00441   A = mA [0000] The exemplary maximum current the LED can operate safely can be about 20 mA.", "(See, e.g., Reference 3).", "As the values of I 1 , I 2 , and I 3 can be lower than the maximum current, it can be concluded that the LED's are working safely.", "Exemplary Transistors [0061] Two or more NPN transistors can be used.", "NPN transistors can have three pins, collector 705 (“C”), base 710 (“B”), and emitter 715 (“E”), as shown in FIG. 7 .", "Current can flow from C to E depending on the input of B. For a NPN transistor, the current that flows into C (I c ) can be the amplified version of the current that flows into B (I b ).", "The DC current gain, h FE , can be defined as the ratio of I c over I b (See, e.g., Reference 4).", "The h FE can signify a linear relationship between the input current I b and output current I c .", "[0062] The transistors in the exemplary pressure regulating unit/device/apparatus/system/arrangement can be used to control the air pump and the solenoid valve, as both components can utilize a large amount of current that cannot be obtained from the Arduino alone.", "The exemplary transistors can be configured as switches that can control the air pump and the solenoid valve based on I b .", "Switching transistors may need saturation, as only two states—“on”", "and “off”", "can exist for saturated transistors.", "(See, e.g., Reference 6).", "Saturation in a transistor can usually be done by inputting large I b such that I c becomes independent of the gain.", "Thus, I c can remain constant as long as I b may not be zero (e.g., On), and I c can become zero when I b can be zero (e.g., Off).", "The transistor can be saturated when I b can be approximately of [0000] 1 10  I c .", "[0063] The exemplary air pump and solenoid valve can be powered by a 9V battery 805 , and can be connected according to the transistor circuit shown in FIG. 8 .", "The operating currents of the air pump and the solenoid valve can be about 380 mA and about 75 mA, respectively, when the power supply can be capable for outputting these currents.", "(See, e.g., References 7 and 8).", "Thus, by modeling the air pump and solenoid valve as load resistors 810 , the corresponding I c values of the air pump and solenoid valve can be equal to the operating currents.", "The current I b can then be determined and can consequently be R b .", "Exemplary Air Pump and Solenoid Valve [0064] To saturate transistors T 1 and T 2 , I b can be chosen as about 28 mA and about 7 mA, for the air pump and the solenoid valve, respectively.", "Using Ohm's Law (e.g., Equation 8), the resistances of the resistors connecting to pin B (R b ) can be determined as, for example: [0000] R b = 5   V 0.028   A ≈ 180   Ω   ( Air   Pump ) R b = 5   V 0.007   A ≈ 720   Ω   ( Solenoid   Valve ) [0000] Thus, an approximately 180Ω resistor (e.g., R 2 ) can be connected to pin B of transistor T 2 for the air pump (see e.g., Table 2 and FIG. 5 ).", "An approximately 720Ω resistance can be achieved by connecting two approximately 360Ω resistors (e.g., R 3 &", "R 4 ) in series for the solenoid valve.", "(i.d.).", "Induced Voltage Estimation [0065] The air pump and the solenoid valve can be electromechanical components that contain solenoids (e.g., coils).", "Solenoids can induce electromotive force (“EMF”), or voltage, when magnetic flux through the solenoid changes with time.", "This is known as Faraday's Law.", "Faraday's Law can be shown in the following exemplary formula (see, e.g., Reference 9): [0000] ɛ = - N   ∅ B  t ( 9 ) [0000] where ε can be the induced voltage EMF, N can be the number of loops, [0000]  ∅ B  t [0000] can be the derivative of magnetic flux (φ B ) with respect to time (t).", "[0066] Magnetic flux in Equation 9 can be defined as the surface integral of the dot product of magnetic field, and the normal vector to an area where magnetic field lines pass through.", "(See, e.g., FIG. 9 ).", "Magnetic flux can be calculated using exemplary Equation 10.", "(See, e.g., Reference 10).", "[0000] φ B = {right arrow over (B)}·d{right arrow over (A)}=AB cos(θ) (10) [0000] where {right arrow over (B)} can be magnetic field with magnitude B, {right arrow over (A)} can be the normal vector of the area magnetic field lines pass through with area A, and θ can be the smallest angle between the two vectors.", "[0067] As shown in FIG. 9 , the solenoid can produce magnetic fields based on the current.", "The Magnetic field produced by the solenoid can be calculated using Equation 11 (see, e.g., Reference 11), where, for example: [0000] B = μ 0  N l  I ( 11 ) [0000] where μ O can be the permeability of free space, l can be the length of the solenoid, and I can be the current in the solenoid.", "[0068] Since the magnetic field produced inside of the solenoid can be parallel to the normal vector of the cross-sectional area of the solenoid (see, e.g., FIG. 5 ), the surface integral and dot product in Equation 10 can be simplified to exemplary Equation 12 (cos(0°)=1).", "[0000] φ B =BA (12) [0000] Combining Equations 9, 11 and 12, an expression for induced voltage due to the change of current in the solenoid can be obtained as, for example: [0000] ɛ = - A   μ 0  N 2 l   l  t ( 13 ) [0000] Equation 13 can relate the change of current to the voltage induced by the solenoid.", "The term [0000] A   μ 0  N 2 l [0000] can be known as the inductance of the solenoid.", "According to this formula, when the air pump and the solenoid valve can be turned off, the current can suddenly decrease to zero.", "A sudden decrease in current [0000] (  l  t <", "0 ) [0000] can induce a positive EMF (ε) with respect to the ground as shown in FIG. 10 .", "These exemplary induced voltages, together with the 9V battery, can produce large currents toward the transistors, can enter the ground pin of the Arduino, and can damage the two components.", "FIG. 11 illustrates an exemplary circuit diagram of the exemplary current redirection by the exemplary pressure regulating unit/device/apparatus/system/arrangement.", "Exemplary Protective Diode [0069] One solution to avoid the potential damage of the prototype due to the induced voltages can be to connect a diode parallel to the exemplary solenoid (see, e.g., Reference 13) (e.g., air pump and solenoid valve) as shown in FIG. 7 .", "The diodes (e.g., D 1 and D 2 shown in FIG. 5 ) connected across the solenoid valve and the air pump can be termed protective diodes and can complete the short circuits that redirect the induced currents back to the solenoids, thus preventing damage to the rests of the circuitry.", "Exemplary Air Pump Flow Rate and Applied Pressure Estimation [0070] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be used to apply pressure to the patient's arm through inflation of the inflatable cuff by air.", "By assuming air as an ideal gas, the cuff pressure can be predicted using the ideal gas law, which can be, for example: [0000] PV=nRT (14) [0000] where P can be the absolute pressure, V can be the volume, n can be the number of molecules, R can be the gas constant, and T can be the absolute temperature.", "[0071] While encircling a patient's arm, the inflatable cuff can only hold a specific volume.", "When this volume can be reached, the number of molecules can increase due to the input of air by the pump while the volume remains unchanged.", "If the air pump's volumetric flow rate can be Q, the gauge pressure of the inflatable cuff, P, can be calculated using the following exemplary formula derived from the ideal gas law: [0000] P = RT  ( ρ + Q   ρ   t V ) + P L - P atm ( 15 ) [0000] where ρ can be the density of air, [0000] n v , [0000] Q can be the volumetric flow rate, P L can be the load pressure, and P atm can be the atmospheric pressure.", "[0072] The term Qρt in Equation 15 can be the number of molecules pumped into the inflatable cuff in time t due to volumetric flow rate of Q (e.g., Qρ can be molar flow rate of air).", "P L can be the load pressure defined as the pressure that the air pump operates against.", "It can also be that the pressure remains in the cuff due to the previous pumping.", "Because the pressure in the ideal gas law can be the absolute pressure, atmospheric pressure P atm can be subtracted to obtain the applied pressure, which can be a gauge pressure.", "Since air can be assumed to be an ideal gas, the term RTρ can be the same as atmospheric pressure, and the two terms can cancel out.", "Equation 15 can then be simplified to, for example: [0000] P = RT   ρ V  ( Qt ) + P L ( 16 ) [0073] If the volumetric flow rate Q of the air pump can be known, the applied pressure can be calculated or otherwise determined using Equation 16.", "However, the volumetric flow rate can be a function of load pressure P L .", "Exemplary Air Volumetric Flow Rate [0074] The exemplary air pump can have a volumetric flow rate curve under the zero-load current of 155 mA.", "(See, e.g., Reference 8).", "This curve can follow a typical exponential decay and can be approximated by the following exemplary equation: [0000] Q= 1.33·10 −5 ·e −0.0046 P L (17) [0075] In the exemplary device, the zero-load current can be about 380 mA.", "If it can further be assumed that the volumetric flow rate curve can maintain its shape, but the magnitude can change linearly with the zero-load current, the volumetric flow rate for 380 mA can be obtained as, for example: [0000] Q= 3.27·10 −5 ·e −0.0046P L (18) [0000] Equation 18 is plotted in FIG. 12 .", "When the load pressure, or pressure that exists inside the cuff due to previous pumpings increases, the volumetric flow rate can decrease.", "Exemplary Applied Pressure Estimation [0076] By substituting Equations 18 into Equation 16, the applied pressure as a function of the load pressure, or the pressure existing in the cuff, can be obtained as, for example: [0000] P = 3.27 * 10 - 5 * RT   ρ   t V   - 0.0046  P L + P L ( 19 ) [0000] Because of the stepwise application of pressure in the exemplary device, Equation 19 can be used to estimate the newly applied pressure to the arm using the existing pressure in the cuff (P L ).", "Exemplary Blood Flow Modeling [0077] Blood flow through arteries and veins can be determined by utilizing the conservation of mass principle, which states that the rate of accumulation of mass in a control volume can equal the difference between the flows of mass into and the mass out of the control volume, as shown in FIG. 13 .", "Exemplary Poiseuille Flow [0078] The flow of blood can be assumed to be a pressure-driven laminar flow of an incompressible Newtonian fluid (e.g., blood) through a cylindrical tube (e.g., blood vessel).", "Such a case can be known as the Poiseuille flow.", "[0079] The flow can be unidirectional along the longitudinal axis.", "When it can be fully developed, the velocity of blood can be a function of radius only, and can be expected to exhibit maximum velocity with a radial symmetry about the centerline.", "The velocity profile under these assumptions is shown in FIGS. 14A , which illustrates laminar flow of a Newtonian fluid through a cylinder, and 14 B, which illustrates a momentum balance on a differential volume.", "[0080] Since the flow can be steady, the sum of all forces can be equal to zero, and the only relevant forces can be pressures and shear stresses.", "Under these assumptions, the Navier-Stokes Equation in the z-direction (e.g., exemplary Equation 20) can be simplified to exemplary Equation 21.", "[0000] ρ  ( ∂ V z ∂ t + V r  ∂ V z ∂ r + V 0 r  ∂ V z ∂ θ + V z  ∂ V z ∂ z ) = -  P  Z + μ  [ 1 r    r  ( r   V z  r ) + 1 r 2  ∂ 2  V z ∂ θ 2 + ∂ 2  V z ∂ z 2 ] + ρ   g z ( 20 )  0 = -  p  z + μ r    r  ( r   V z  r ) ( 21 ) [0000] where P can be pressure, z can be the longitudinal direction, μ can be viscosity, r can be the radial direction, and V z can be the velocity in the z-direction.", "[0081] In Equation 21, pressure P can be a function of z, and velocity V z can be a function of r. The only situation where the sum of the derivatives of a function of z and a function of r can be zero is when they both can be constants.", "By integrating the pressure gradient as a constant with boundary conditions (“BC”), the following, for example, can be obtained: [0000] P (0)= P O and P ( L )= P L (BC: Pressure) [0000] and the pressure distribution can be obtained as, for example: [0000] P  ( z ) = P o - P L L  z + P o ( 22 ) [0000] where P O can be the pressure at the origin (e.g., the heart), L can be the distance from the origin, and P L can be the pressure at a distance L (e.g., the extremity).", "[0082] By taking the derivative of Equation 22 with respect to z, and substituting the expression into Equation 21, the differential equation of V z can be obtained as, for example: [0000] P o - P L L = μ r    r  ( r   V z  r ) ( 23 ) [0000] The general solution to Equation 23 can be, for example: [0000] V z  ( r ) = ( P o - P L )  r 2 4  Lu + C 1   ln  ( r ) + C 2 ( 24 ) [0000] where C 1 and C 2 can be constants of integration.", "[0083] By using the following boundary conditions, the velocity profile V z can be obtained as, for example: [0000] V z  ( R ) = 0   and    V z  r  ( 0 ) = 0 ( BC  :   Velocity ) [0000] and, for example: [0000] V z  ( r ) = ( P 0 - P L )  R 2 4  L   μ  ( r 2 R 2 - 1 ) ( 25 ) Exemplary Blood Volumetric Flow Rate [0084] The volumetric flow rate of blood Q B (e.g., Equation 27 below) can be obtained by integrating the velocity over the cross-sectional area of the blood vessel.", "Thus, for example [0000] Q B = ∫ 0 R  V z  ( r )  2  π   r   r ( 26 ) Q B = ( P o  P L )  π   R 4 8  L   μ ( 27 ) [0085] The exemplary pressure regulating unit/device/apparatus/system/arrangement can be used to apply pressure between the systolic and diastolic pressures.", "The brachial artery and the cephalic vein are the two main blood vessels in the upper arm that can receive the applied pressure.", "The diameter of the brachial artery can be approximately 3.52 mm, (see, e.g., Reference 16), and the diameter of the cephalic vein can be about 2.4 mm.", "(See, e.g., Reference 17).", "The cephalic vein can be assumed to be occluded when the applied pressure can be higher than the diastolic pressure.", "The brachial artery can be assumed be occluded if the applied pressure can be higher than the systolic pressure.", "The radii can be described using the following exemplary equations for the brachial artery and the cephalic vein, respectively, by assuming the radii decrease linearly when the applied pressure can be increased: [0000] R A = { 0.00176 - 0.00176 SP  P , 0 ≤ P ≤ SP 0 , P >", "SP ( 28 ) [0000] and, for example: [0000] R V = { 0.0012 - 0.0012 DP  P , 0 ≤ P ≤ DP 0 , P >", "DP ( 29 ) [0086] The radii can be redefined to zero when the applied pressure can be greater than the systolic pressure, and the diastolic pressure for the brachial artery and the cephalic vein, respectively, since negative radii can be physically impossible.", "[0087] The flow rate in Equation 27 can assume blood to be a Newtonian fluid.", "However, blood's behavior can depend on shear rate (e.g., velocity gradient).", "A more sophisticate model of blood flow can be shown as, for example: [0000] Q B = π   R 4  Δ   P 8  η N  L  [ 1 + 11 21  ( τ 0 τ w ) 4 - 16 7  ( τ 0 τ w ) + 8 3  ( τ 0 τ w ) ] ( 30 ) [0000] (see, e.g., Reference 18) where R can be radius of the blood vessel, P can be pressure, η N can be blood viscosity at high shear rate, L can be the length of the blood vessel, τ O can be yield stress of blood, and τ W can be shear stress at the wall of the blood vessel.", "Exemplary Hoop Stress Analysis Exemplary Hoop Stress [0088] The inflatable cuff can be wrapped around the upper arm to apply a pressure.", "The pressure the exemplary device/apparatus can apply can be approximately 220 mmHg depending on different individuals.", "In the presence of an exerted pressure, the walls of blood vessels can contract.", "Therefore, the blood vessels can resist the contraction force with a hoop stress in the circumferential direction to avoid any vessel damage.", "The hoop stress can have vital physiological significance.", "It can be the primary force in regulating blood vessel wall thickness and residue stress, in response to blood pressure and hypertension.", "(See, e.g., Reference 19).", "Assuming that the blood vessels can be very thin, the hoop stress can be calculated using, for example: [0000] σ θ = Pr t ( 31 ) [0000] (see, e.g., Reference 20) where τ θ can be the hoop stress, P can be pressure, r can be radius, and t can be thickness.", "Exemplary Hoop Stress Calculation [0089] The exemplary dimensions for the brachial artery and the cephalic vein are summarized in Table 4 below.", "The hoop stresses can be calculated using Equation 31 at a maximum pressure of about 220 mmHg The hoop stresses calculated from previous experimental studies are included in the table as references to determine the accuracy of the exemplary calculation.", "[0000] TABLE 4 Dimensions of the Blood Vessels, Calculated Hoop Stresses and Reference Hoop Stresses.", "Brachial Artery Cephalic Vein Thickness (t) 0.35 mm 1.35 mm Diameter (2r) 3.52 mm 2.40 mm Radius/Thickness 5.03 0.89 (r/t) Calculated 147.5 kPa 26.1 kPa Hoop Stress Reference Hoop 100 kPa- 245 kPa Stress 280 kPa Exemplary Blood Vessel Damage Analysis [0090] One of the purposes of the hoop stress analysis can be to ensure that the maximum applied pressure of about 220 mmHg does not cause any damage to blood vessels.", "According to one study, most human arteries'", "can yield hoop stresses which can be in the order of 10 5 Pa (e.g., 100 kPa).", "(See, e.g., Reference 19).", "In another study, most mammalian arteries can be expected to exert hoop stress between about 240 kPa and about 280 kPa at about 100 mmHg.", "(See, e.g., Reference 23).", "In the exemplary analysis, the brachial artery can exert about 147.5 kPa at the maximum pressure of about 220 mmHg.", "Since 147.5 kPa can be in the order of about 10 5 Pa and much less than about 240 kPa, the exemplary device does not cause any damage to the brachial artery.", "Similarly, the cephalic vein can be found to exert a hoop stress of about 245 kPa at the mean arterial pressure under normal physiological conditions.", "(See, e.g., Reference 22).", "In the exemplary analysis, the hoop stress for cephalic vein can be calculated to be about 26.1 kPa at the maximum pressure of about 220 mmHg.", "Since 26.1 kPa can be much less than about 245 kPa, the pressure exerted from the exemplary device will not damage the cephalic vein.", "[0091] FIG. 15 shows a block diagram of an exemplary embodiment of a system according to the present disclosure.", "For example, exemplary procedures in accordance with the present disclosure described herein can be performed by a processing arrangement and/or a computing arrangement 1502 .", "Such processing/computing arrangement 1502 can be, for example, entirely or a part of, or include, but not limited to, a computer/processor 1504 that can include, for example, one or more microprocessors, and use instructions stored on a computer-accessible medium (e.g., RAM, ROM, hard drive, or other storage device).", "[0092] As shown in FIG. 15 , for example, a computer-accessible medium 1506 (e.g., as described herein above, a storage device such as a hard disk, floppy disk, memory stick, CD-ROM, RAM, ROM, etc.", ", or a collection thereof) can be provided (e.g., in communication with the processing arrangement 1502 ).", "The computer-accessible medium 1506 can contain executable instructions 1508 thereon.", "In addition or alternatively, a storage arrangement 1510 can be provided separately from the computer-accessible medium 1506 , which can provide the instructions to the processing arrangement 1502 so as to configure the processing arrangement to execute certain exemplary procedures, processes and methods, as described herein above, for example.", "[0093] Further, the exemplary processing arrangement 1502 can be provided with or include an input/output arrangement 1514 , which can include, for example, a wired network, a wireless network, the Internet, an intranet, a data collection probe, a sensor, etc.", "As shown in FIG. 15 , the exemplary processing arrangement 1502 can be in communication with an exemplary display arrangement 1512 , which, according to certain exemplary embodiments of the present disclosure, can be a touch-screen configured for inputting information to the processing arrangement in addition to outputting information from the processing arrangement, for example.", "Further, the exemplary display 1512 and/or a storage arrangement 1510 can be used to display and/or store data in a user-accessible format and/or user-readable format.", "[0094] According to further exemplary embodiments of the present disclosure, it can be possible to provide certain exemplary changes to the system according to the exemplary embodiment of the present disclosure.", "For example, it can be possible to utilize a standard 9V alkaline battery, although a use of a 9V lithium battery can provide an extended capacity (e.g., which can be as much as 3 times) greater than a 9V alkaline battery.", "In addition, for example, it can be possible to provide a configuration which can effectuate a reverse battery protection.", "A further exemplary solenoid valve can be provided which can have a higher voltage capacity, and which can lower power consumption.", "Further, instead of or together with the external release valve, it can be possible to utilize an integral release valve.", "[0095] In additional exemplary embodiments of the present disclosure, another exemplary circuit board can be provided for the use with the exemplary system according to the present disclosure.", "For example, as shown in FIG. 16 , such exemplary circuit board can be laid out for a top mounted power switch and LED indicators, and can be placed in a SERPAC enclosure, as shown in FIGS. 17A and 17B (providing top front and top rear views thereof).", "Holes can be machined to provide access to the internal works.", "Nomenclature can be silkscreened onto the enclosure.", "A 9V battery compartment on the rear of the exemplary enclosure provides for battery replacement without disassembly.", "[0096] Thus, according to such exemplary embodiment of the present disclosure, as illustrated in FIG. 18 , a standard blood pressure cuff 1805 can be used with the exemplary system 1810 shown in FIGS. 16, 17A and 17B .", "For example, the pump bulb can be removed, and the release valve and cuff can be attached using Luer connectors.", "The pressure gauge can be attached to the cuff.", "The finger sensor can be replaced by a Nelcor compatible SpO 2 adult finger unit and attached to the PST via, for example, a standard 9 pin serial port connector or using other known connectors.", "[0097] FIG. 19 shows an exemplary schematic diagram of the exemplary circuit board illustrated in FIG. 16 , and FIGS. 20A-20H shows various view of sections of the layout of the exemplary printed circuit.", "[0098] The foregoing merely illustrates the principles of the disclosure.", "Various modifications and alterations to the described embodiments will be apparent to those skilled in the art in view of the teachings herein.", "It will thus be appreciated that those skilled in the art will be able to devise numerous systems, arrangements, and procedures which, although not explicitly shown or described herein, embody the principles of the disclosure and can be thus within the spirit and scope of the disclosure.", "Various different exemplary embodiments can be used together with one another, as well as interchangeably therewith, as should be understood by those having ordinary skill in the art.", "In addition, certain terms used in the present disclosure, including the specification, drawings and claims thereof, can be used synonymously in certain instances, including, but not limited to, for example, data and information.", "It should be understood that, while these words, and/or other words that can be synonymous to one another, can be used synonymously herein, that there can be instances when such words can be intended to not be used synonymously.", "Further, to the extent that the prior art knowledge has not been explicitly incorporated by reference herein above, it is explicitly incorporated herein in its entirety.", "All publications referenced are incorporated herein by reference in their entireties.", "EXEMPLARY REFERENCES [0099] The following references are hereby incorporated by reference in their entirety.", "[1] Steinke J M. 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BACKGROUND OF THE INVENTION The present invention relates to the field of electronic document management, more specifically to document management systems where a target document is retrieved using an example of content of the target document. U.S. Pat. No. 5,464,353, issued to Jonathan Hull, et al. (application Ser. No. 08/222,281 filed Apr. 1, 1994 and currently pending) entitled "Image Matching and Retrieval by Multi-Access Redundant Hashing" (incorporated by reference herein and referred to as "Hull") disclosed a new method for retrieving a document from a document management system where the input to the system is a sample page from the target document. In that system, descriptors are extracted from each document being stored and those descriptors are stored in a descriptor database. To retrieve a target document, only a sample page or portion of a page is needed. The sample page is presented to the document management system, descriptors are extracted from the sample page and then they are matched to descriptors in the descriptor database. Since many descriptors are taken from each stored document and from the sample page, they are redundant. As explained by Hull, where many descriptors might match between the target document and the sample page, but errors are not fatal to the search. In that system, documents accumulate votes based on matches of descriptors and the document with the highest vote count is returned as the target document. Of the descriptors disclosed by Hull, graphical descriptors looked to key features of the graphics on a page, whereas text descriptors looked to the pattern of letters or word lengths. However, the document management system of Hull uses an optical character recognition system to recognize characters from a digitized image of a page of a document or a sample page in order to form the descriptors for the page image. Since this is a computationally expensive operation, a more efficient method for generating descriptors from text is needed. SUMMARY OF THE INVENTION An improved document management system with high-speed retrieval by example is provided by virtue of the present invention. In one embodiment, the pages of documents scanned to be included in the storage of the document management system and the sample pages scanned as part of a retrieval process are described by descriptors that are extractable from the page with little computational effort. In a particular embodiment, bounding boxes are formed around connected components and the interbox spacings are measured. A histogram of interbox spacings is found and a threshold value is determined, with spacings less than the threshold deemed to be intercharacter spacing and the spacings larger than the threshold deemed to be interword spacings. The pattern of spacings is then translated into descriptors. In another embodiment, where interword spacing is rare, such as with Japanese text or other text which uses two alphabets with different densities, the histogram is of the pixel density of the bounding boxes instead of the interbox spacing. To address breaks in characters, overlapping bounding boxes may be combined into a single bounding box. If necessary, a language detection preprocessor could be used to detect the language of a document and apply the appropriate descriptor extraction. In a document where character spacing is regular, the intercharacter spacing can be used to further define the bounding boxes. The document management system, or just the query portion of the document management system might be tied into a copier. In such an embodiment, a user would need only to submit the sample page to the copier and the copier would retrieve the target document and print it. In alternate embodiments, the speech and text documents are used interchangeably as reference documents and large documents. The descriptors for a speech document can be either the pattern of phonemes per word or letters per word. In the former, a phoneme identifier is used and the phoneme identifier can identify interword silences. In the latter, a speech recognizer is used and the speech is converted to text which is then used as the basis for descriptor generation. A further understanding of the nature and advantages of the inventions herein may be realized by reference to the remaining portions of the specification and the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a document management system according to the present invention. FIG. 2 is a block diagram of a descriptor generator which generates descriptors based on patterns of error character spacing. FIG. 3 is a block diagram of a descriptor generator which generates descriptors based on pixel density. FIG. 4(a) is an illustration of a document image. FIG. 4(b) is a closer view of a portion of the text area show in FIG. 4(A). FIG. 5 is a graphical representation of a histogram of intercharacter spacing. FIG. 6 is a image of a document containing Japanese characters. FIG. 7(a) is an image of a Japanese character. FIG. 7(b) is an image of the Japanese character shown in FIG. 7(a) with bounding boxes generated for portions of the Japanese character. FIG. 7(c) is an image of the Japanese character shown in FIGS. 7(a) and 7(b) with a single bounding box enclosing substantially all the character. FIG. 8 is a graphical representation of a histogram of pixel densities. FIG. 9 is a flow chart of a process of storing documents in a document database and retrieving documents by example. FIG. 10 a flow chart of a process of generating descriptors for a document. FIG. 11 is a block diagram of an alternate embodiment of a descriptor generator wherein the input documents are speech and the descriptors are based on the number of phonemes per word. FIG. 12 is a block diagram of an alternate embodiment of a descriptor generator wherein the input documents are speech and the descriptors are based on the number of letters per word. FIG. 13 is a flow chart of a process of storing reference speech passages and retrieving speech passages by example using target speech passages. FIG. 14 is a flow chart of a process of retrieving speech passages by example using both phoneme recognition and speech text recognition. DESCRIPTION OF THE PREFERRED EMBODIMENTS The figures first show two embodiments with some elements in common. In one embodiment, intercharacter spacing is used to distinguish one document from another. The second embodiment uses character density to distinguish documents, followed by alternative embodiments where reference documents and/or target documents are in speech and/or text form. In general, these two systems work the same way and might even be used together. Before a document can be retrieved from a document database, the document database must be generated. To generate the database, documents are input. If the documents exist only on paper form, they are scanned to produce electronic, digitized representations of the documents. If the documents already exist in electronic form, the scanning step is not needed. For each document, a set of descriptors are generated. A descriptor is a pattern of metrics for part of the document. For example, if the metric is character spacing and the metric has one of two values (for example 1="interword space" and 0="intraword space"), a bit pattern can be generated for some or all of the document. Alternatively, the bit pattern is compressed into a string of word lengths. The bit pattern or word length pattern is then used as the descriptor. Typically, many descriptors are taken from a document and the descriptors may contain errors. However, if enough descriptors are taken, the errors will be filtered out, as explained in Hull. These descriptors are stored in an index and the document is stored in the document database. To retrieve a document by example, all or part of a target document is input to the system. The matching document is the document in the document database which has the most descriptors in common with the target document. Of course, the requirements for matching documents could be relaxed so that multiple matching documents are found, not just the most promising candidate. These multiple matching documents might then be presented to the user for manual selection of the correct document. The descriptors for the target document are obtained the same way the descriptors for the documents in the document database are obtained. Because the target document descriptors are obtained in the same way, the process of determining character bounds does not need to be correct, just consistent. The same is true for the process of measuring the metric. Thus, it is expected that some intraword spacings will be labelled as interword spacings, but since the same labelling occurs in the document database as with the target document, descriptors will match even though the labelling is not an accurate labelling of interword spacing. FIG. 1 is a block diagram of a document retrieval system 10, which includes an intake processor 12 for an input document 14, a document database 16, a descriptor database 18, a query processor 20 for processing a sample page 22 of a target document and for outputting the target document 24 which "matches" sample page 22. Both intake processor 12 and query processor 20 include a high-speed descriptor generator 40. Intake processor 12 accepts input documents, such as input document 14, and stores them into document database 16 while generating descriptors for the input document and storing the descriptors in descriptor database 18. Query processor 20 accepts sample page 22 and generates descriptors for the sample page using its descriptor generator 40. Of course, in some embodiments, only one descriptor generator is used and is shared between intake processor 12 and query processor 20. Query processor 20 is coupled to descriptor database 18 in order to apply descriptors to descriptor database 18 and have returned to it matches identifying documents in document database 16 which have descriptors in common with sample page 22. Query processor 20 is also coupled to document database 16 in order to retrieve documents based on the document identifiers obtained from the description database. Query processor 20 has an output from which a matching document (target document 24) is presented. In some embodiments, the output takes the form of a copier output which prints the target document. Query processor 20 might also include an interactive apparatus to allow a user to select from among more than one closely matching document (candidate documents). FIGS. 2 and 3 show descriptor generators in further detail. FIG. 2 is a block diagram of a descriptor generator 40A which generates descriptors based on word spacing (or approximations thereto). FIG. 3 is a block diagram of a descriptor generator 40B which generates descriptors based on pixel density. Referring to FIG. 2, descriptor generator 40A is shown comprising a segmenter 102, a box identifier 104, a histogram generator 106, a labeller 108A, and a descriptor writer 110A. Segmenter 102 inputs an image file 112 and outputs a segmented image 114. Box identifier 104 inputs this segmented image 114 and outputs box locations 116. Histogram generator 106 inputs these box locations 116 and outputs a histogram 118A of interbox spacing. Labeller 108A uses box locations 116 and histogram 118A as inputs to generate a set of word patterns 120, which is input to descriptor writer 110A, which outputs a set of descriptors 122 for image file 112. Image file 112 of FIG. 2 corresponds in FIG. 1 to an image of input document 14 or sample page 22. Segmenter 102 analyzes image file 112 and determines which areas of the image are text, figures, line art, or blank space. This allows down-stream elements of descriptor generator 40 to limit their work to the text areas of input image 112. Of course, as shown by Hull, the graphical areas of the image might also be used to generate descriptors. The text areas of image file 112 are stored as segmented image 114. Of course, depending on storage requirements and limitations, segmented image 114 could be limited to the text areas of image file 112, or segmented image 114 could be represented by nothing more than pointers to locations in the storage for image file 112. However the text areas are stored, box identifier 104 processes those text areas to locate bounding boxes around characters. FIG. 4(a) shows one such text area and FIG. 4(b) shows a subset of that text area (enlarged) with bounding boxes drawn around characters. There the bounding boxes are rectangles which surround regions of continuous black pixels. Only regions which are above a threshold size are considered; note that the dots of the "i" characters (402) and the periods (406) are ignored. Since these discrepancies between the bounding box and the actual bounds of the character are discrepancies in both input documents and target documents, they do not result in any errors. Breaks in characters due to poor copying might cause the character bounding boxes to exclude portions of boxes, such as with bounding boxes 408. While these discrepancies might cause errors, given the number of descriptors taken the target document and the matching document should still have more descriptors in common than the target document and a nonmatching document. In some embodiments, box identifier 104 performs an additional test on bounding boxes 116 to ensure that they are more or less lined up horizontally. This might be done by identifying the lines of text within the text areas, then identifying a baseline for each line of text and using the baseline as a guide for the location of bounding boxes. Once the bounding boxes are determined, their position on the image is noted and stored as box locations 116. Histogram generator 106 reads these box locations and calculates interbox spacing. If the distribution of interbox spacing is measured and a histogram is crested, two peaks should occur. An example of this is shown in histogram 118A of FIG. 2 which is represented in FIG. 5 graphically. This is a graph of pixel spacings between successive character bounding boxes for the text area shown in FIG. 4(a). Histogram 118A has two peaks, one for a spacing of around 5 pixels and one for a spacing of around 25 pixels. A minimum occurs between the two peaks, at around 16 pixels. Thus, for this data, a space of less than 16 pixels is probably an intraword space and a space of more than 16 pixels is probably an interword space. Labeller 108A uses that threshold to label each interbox space as either interword or intraword. Strictly speaking, labels are associated with the spaces between bounding boxes not the bounding boxes themselves. However, except for the last bounding box on each line of text, there is a one-to-one correspondence between bounding boxes and spaces, so the labels could just as easily be associated with the bounding boxes. In the latter case, if the label for a space is associated with the bounding box at the left of the space, then each bounding box might be characterized as bounding either a word-ending character or a non-word-ending character. Either way, the essential pattern of labels is the same. For example, if the text being processed is: "A sample sentence appears here." the pattern of spaces might be: "S-----S-------S------S---S" where '-' indicates an intraword space and 'S' indicates an interword space. Note that the '.' at the end of the sentence did not qualify for a bounding box and is therefore not considered, and an interword space following the end of each line is assumed. If instead, the labels '-' and 'S' were affixed to non-word-ending characters and word-ending characters, respectively, the same pattern would emerge. If expressed in binary, where '0' replaces '-' and '1' replaces 'S', the pattern would be: "1000001000000010000001000". This binary pattern could be compressed with run-length encoding to "16874" which is just the pattern of word lengths. The above example assumed that the bounding box locations were such that no intraword space was greater than the threshold and no interword space was less than the threshold. If there were, the pattern might be different, but it would be the same pattern both when the text was input and when the text was used for querying. In some embodiments, it might be desirable to fix the threshold ahead of time. If the threshold is fixed ahead of time, at say 16 pixels, then the histogram does not need to be created, as each space can be labelled as it is measured. It is not always desirable to fix the threshold, however. If the target document can be submitted with different scales or scanned at different resolutions, then the number of pixels at the minimum of the distribution of interbox spacing will vary and should be calculated each time for the particular image being used. Once word patterns 120 are generated by labeller 108A, they are formed into descriptors 122 by descriptor writer 110A. In one specific embodiment, a descriptor is the hashed concatenation of a set number of word lengths. These descriptors are then used as taught in the above description of FIG. 1. FIG. 3 is a block diagram of a descriptor generator 40B which is similar to descriptor generator 40A, except that descriptor generator 40B generates descriptors based on pixel density rather than interbox spacing. As with descriptor generator 40A, descriptor generator 40B includes a segmenter 102, a bounding box identifier 104, and the descriptor generator processes an input file 112 and generates segmented image 114 and box locations 116. Descriptor generator 40A also includes several elements which perform functions analogous to elements in descriptor generator 40B: a histogram generator 106B which generates a histogram 118B, a labeller 108B which generates density patterns instead of word patterns, and a descriptor writer 110B which writes descriptors based on density patterns rather than word patterns. Descriptor generator 40B also contains elements which have no analogy in descriptor generator 40A: a refiner 124 for refining box locations (optional), a pixel density counter 126 coupled to receive segmented image 114 and coupled to either refiner 124 (if used) or to receive box locations 116, and storage for pixel densities 128. In descriptor generator 40B labeller 108B is coupled to receive box locations 116, pixel densities 128 and histogram 118B. As with descriptor generator 40A, if a fixed threshold is used, histogram 118B is not needed. However, in contrast with descriptor generator 40A, the operation of descriptor generator 40B might be independent of the scales and scanning resolutions used, since the threshold is a pixel density not a spacing. In operation, segmenter 102 reads the input file 112 and segments it into text and other areas. The segmented image 114 is read by box identifier 104 to generate a list of box locations 116. An example of an image which might be contained in input file 112 or segmented image 114 is shown in FIG. 6 with the bounding boxes added as indicated by box locations 116. Although FIG. 6 shows an image of Japanese characters, non-Japanese text with characters having a variable pixel density can also be processed by this apparatus. With Japanese characters, the distribution of pixel densities should have two peaks, one representing Japanese Kanji characters and the other representing Japanese Kana characters. The Kanji characters were originally derived from the Chinese ideograms and tend to have more strokes, while the Kana characters, which are from a syllabic alphabet, have fewer strokes. Unlike the 26-letter Latin alphabet, Japanese characters are often made up of unconnected strokes, and a single character might be boxed by multiple bounding boxes. For example, FIG. 7 shows one Japanese character being bounded. FIG. 7(a) shows the character before the bounding boxes are generated and FIG. 7(b) shows two bounding boxes 704, 706 overlaid on three unconnected elements of the character. Stroke which do not have enough pixels to qualify as their own elements are not bounded. The optional refiner 124 refines the bounding box process by joining overlapping bounding boxes on the assumption that they cover elements of the same character. Refiner 124 locates a rectangle which encloses all of the overlapping boxes. Thus, as shown in FIG. 7(c), the bounding box 710 would result and would replace boxes 704 and 706. Whether or not refiner 124 is used, pixel density counter 126 counts the number of pixels in each bounding box and the number of black pixels. As should be apparent, the same effect can be had by counting the white pixels, and if the characters are not black, the count is of the number of pixels making up the character, whatever color or colors it might be. The pixel density is then just the number of black pixels divided by the total number of pixels in the bounding box (normalized density). Alternatively, the bounding boxes can be assumed to all be the same size, or can be forced to be the same size, thus eliminating the need for the normalization step. The pixel densities are stored in storage for pixel densities 128 and used by histogram generator 106B to generate histogram 118B. A graphical representation of an example histogram 118B is shown in FIG. 8. In FIG. 8, the histogram shows the distribution of pixels without normalization. The denser Kanji characters are clustered together in the range of 250 to 450 black pixels, and a threshold of 252 pixels separates the peaks well. It should be noted that some Kanji characters may fall below the threshold and some Kana characters may fall above it. However, so long as the measurement is consistent, a document will have the same descriptors when input as when used as a target document. The threshold can be calculated either by histogram generator 106B or labeller 108B. One way to calculate a threshold is shown by N. Otsu, "A Threshold Selection Method from Gray Level Histograms," IEEE Trans. Systems man and Cybernetics, Vol. smc-9, #1, January, 1979, pp. 63-66. In either case, labeller 108B uses the threshold while reading pixel densities 128 (and box locations 116, if needed for normalization) to assign one of two labels to the character. The two labels might be Kanji/Kana, high/low density (more accurate), or just '1'/'0'. In any case, the labels assigned to consecutive bounding boxes form patterns which are stored as density patterns 130. Density patterns 130 are used by descriptor writer 110B to generate descriptors 122 much the same way word patterns are used in descriptor generator 40A (see FIG. 2). Various apparatus for storing and retrieving documents by example have been described. FIGS. 9-10 are flow charts of a process for document retrieval by example, such as might be performed using the above-described apparatus. FIG. 9 is a flow chart describing a process of storing documents in a document database and retrieving documents matching a target document by the example provided by the target document. At step S1, documents are input into a document storage and retrieval system. At step S2, descriptors are generated for the documents being input. Where text is used as the basis for descriptors, the word spacing determines the descriptors. With speech (see FIGS. 11-12), the patterns of phonemes, the patterns of word lengths, or both are used, where the word lengths are determined using speech recognition to first convert the speech to text. In step S3, following the generation of the descriptors and the input of the documents, the documents are stored in a database and the descriptors are stored in a descriptor database with links to the documents stored in the document database. The next step (S4), is the beginning of a loop which is executed for each target document to be retrieved. In step S4, the target document is input. As explained above, the input need not be the entire target document nor even an entire page of the target document. Next, in step S5, descriptors are generated for the input target document. This step is similar to step S2. Again, if the input document is speech, the descriptors can be based on phoneme patterns as well as word lengths. Next, in step S6, the descriptors generated from the target document are used as indexes into the descriptor database, which yields a list of potentially matching documents. In step S7, the matching documents are retrieved from the document database. If more target documents are to be retrieved, the process continues at step S4, otherwise the process completes. FIG. 10 is a detailed flow chart describing the process of generating descriptors from a document where the document is text or text/graphics. This description applies to input documents whether they are documents initially input to the document database or are portions of target documents. At step S10, the image of the document for which descriptors are to be generated is input to a descriptor generator. The input image is then segmented into text and non-text regions (S 1 ). The descriptor generator analyzes the text segments to find bounding boxes for the characters in text regions (S12). Once the bounding boxes are identified, the descriptor generator generates a histogram of interbox spacings (S13). From this histogram, the descriptor generator determines a threshold between two peaks of the histogram (S14). The descriptor generator then reviews the text region, or at least the pattern of interbox spacing, to label each interbox spacing based on whether it is less than or greater than the threshold determined in step S14 (S15). The descriptor generator then generates descriptors from runs of interbox spacing (S16). The flow chart of FIG. 10 also applies to the process of generating descriptors from pixel density patterns. The difference is that in step S13, the histogram generated is a histogram of pixel densities. Once the histogram is generated, the processes of steps S14, S15 and S16 are performed in the same manner as the above example where the histogram is the histogram of interbox spacing. FIGS. 11-12 are block diagrams of descriptor generators for generating descriptors from speech documents. These speech documents can be either reference documents or target documents. Examples of speech documents are digitized audio of famous speeches, lectures, doctor's comments on patients, pronunciations and the like, however any speech can be used. FIG. 11 is a block diagram of a descriptor generator 40C, where the descriptors are based on phonemes. Descriptor generator 40C includes a phoneme recognizer 802, a "space" recognizer", a labeller 108C and a descriptor writer 110C. Phoneme recognizer 802 reads an input speech document 806 and generates phoneme patterns 808. The phoneme patterns 808 represent the speech, indicating which sounds were emitted and where silences occur. These phoneme patterns 808 are fed to "space" recognizer 804, which isolates the positions of the silence "phonemes" in the recognized speech and passes them to labeller 108C. Labeller 108C and descriptor writer 110C operate like their counterparts in descriptor generators 40A, 40B. The output of labeller 108C is the patterns of "spaces" and words. For example, if speech file 806 contained the spoken phrase "the large car", phoneme recognizer 802 might recognize the phrase as being eleven phonemes and identify the particular eleven phonemes. "Space" recognizer 804 would then identify that the phonemes were two spoken phonemes, a silence phoneme, four spoken phonemes, a silence phoneme, and three spoken phonemes. Labeller 108C would then label the silence phonemes as "spaces", resulting in the pattern 2-S-4-S-3, which descriptor writer 110C would write out as "2-4-3". Even where all the reference documents are speech and the only descriptors are phoneme-based descriptors, a text document could still be used as a target document. The text of the target document is fed through a phoneme generator which generates phonemes from text, and the phonemes would be used to generate descriptors. Of course, with a complex language such as English, an automatic phoneme generator will make errors. However, since the descriptors are redundant, the correct document will generally be found even in the presence of errors. Were both the input document and the reference documents are speech and are described by phoneme patterns, the errors are even less significant if the same phoneme generator is used for both the reference documents and the input documents, since an error common to both does not make a document harder to find. The same is true for text reference documents and speech input documents, or some combination of each. Since phonemes are the unit of speech, the embodiment shown in FIG. 11 is not specific to a particular language. FIG. 12 is a block diagram of a descriptor generator 40D, where the descriptors are based on word length, but are generated for speech documents. Descriptor generator 40D is shown comprising a speech recognizer 902 which also reads a speech document/file 806 as with descriptor generator 40C, but instead of outputting phonemes, speech recognizer 902 outputs the text 906 of the spoken words. Text 906 is processed by space labeller 904, which marks the locations of the spaces in text 906, resulting in word patterns 120, as are described above in connection with FIG. 2. As also described in connection with FIG. 2, word patterns 120 are used by descriptor writer 11OA to generate descriptors 122. Continuing the example used in connection with FIG. 11, if speech file 806 contained the spoken phrase "the large car", speech recognizer 802 might recognize the phrase as being the text: "the large car", and space labeller 904 would output the word pattern "---S-----S---" which would result in the descriptor "3-5-3". FIGS. 13-14 are flow charts illustrating a process of matching speech documents (passages). The process shown in FIG. 13 is similar to the process shown in FIG. 9, except that the process of FIG. 9 covers all combinations of speech and text input and target documents, whereas the processes of FIGS. 13 and 14 deal only with speech passages. Of course, text passages could be converted to "quasi-speech" in the form of phoneme patterns so that documents might be matched on the basis of "sound-alike" matching, but since only the number of phonemes per word is used in descriptor generation, "sound-alike" matching is not needed. In fact, all that is needed is a dictionary of words which includes the number of phonemes for each word, thus serving as a simple look up table. In the process shown in FIG. 13, speech passages are input (S1'), descriptors are generated for them (S2') and the passages and descriptors are stored with links between them (S3'). To retrieve a passage by matching, the target passage is input (S4'), descriptors are generated (S5'), the descriptors are matched (S6') to descriptors in the databases created in step S3', and the matching passages are retrieved (S7'). If more target passages exist, steps S4' through S7' are repeated for those passages. The process shown in FIG. 14 uses both phoneme descriptors and speech text descriptors. The speech text descriptors are essentially the same as the word length descriptors described above--they are generated from the text resulting from speech recognition of the passages. The reference passages are input (S20) and phoneme descriptors are generated (S21) along with text descriptors (S22). These steps can be performed in parallel, but need not be. Next, the phoneme descriptors are stored (S23) and the text descriptors are stored (S24) and the passages are stored (S25) with links between passages and descriptors. To retrieve a passage, the target passage is input (S26), and phoneme descriptors are generated (S27) and text descriptors are generated (S28). Again, these steps can occur in series or parallel. Next, the phoneme descriptors are matched to the stored phoneme descriptors (S29) and the text descriptors are matched to the stored text descriptors (S30) to provide two lists of passages ranked according to how well they matched. The two lists are then merged into a single ranging (S31). It is well known in the art of pattern matching to combine independently generated rankings. See, for example, T. K. Ho, J. J. Hull, S. N. Srihari, "Decision Combination in Multiple Classification Systems", IEEE Transactions on Pattern Analysis and Machine Intelligence, V.16, No. 1, January 1994, pp. 66-75. The above description is illustrative and not restrictive. Many variations of the invention will become apparent to those of skill in the art upon review of this disclosure. Merely by way of example, if the distribution of a metric related to characters has more than two peaks, the distribution might be divided into more than two ranges and the labeller in that case would label each character with more than just a binary label. Also, the text documents can be stored in a variety of formats, such as ASCII files, page description language files such as Postscript™ files, or word processing files such as WordPerfect™ or Microsoft Word™ files. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents.
An improved document management system with high-speed retrieval by example retrieves a document attaching a target document, in whole or part, by comparing descriptors of documents. A descriptor is derived from a pattern of labels, where each label is associated with a character, or more precisely, a character bounding box. A bounding box is found by examining contiguous pixels in an image. The particular label associated with a bounding box depends on the value of a metric measured from that bounding box. In one system, the metric is the spacing between the bounding box and an adjacent bounding box, in which the labels approximately reflect a pattern of word lengths. In other systems, where words lengths are not present, the metric might be pixel density and the pattern of labels approximately reflect a pattern of denser characters and sparser characters. The document management system, or just the query portion of the document management system could be part of a copier, where a sample page is input to the copier and the copier retrieves the matching document and prints it.
Identify the most important claim in the given context and summarize it
[ "BACKGROUND OF THE INVENTION The present invention relates to the field of electronic document management, more specifically to document management systems where a target document is retrieved using an example of content of the target document.", "U.S. Pat. No. 5,464,353, issued to Jonathan Hull, et al.", "(application Ser.", "No. 08/222,281 filed Apr. 1, 1994 and currently pending) entitled "Image Matching and Retrieval by Multi-Access Redundant Hashing"", "(incorporated by reference herein and referred to as "Hull") disclosed a new method for retrieving a document from a document management system where the input to the system is a sample page from the target document.", "In that system, descriptors are extracted from each document being stored and those descriptors are stored in a descriptor database.", "To retrieve a target document, only a sample page or portion of a page is needed.", "The sample page is presented to the document management system, descriptors are extracted from the sample page and then they are matched to descriptors in the descriptor database.", "Since many descriptors are taken from each stored document and from the sample page, they are redundant.", "As explained by Hull, where many descriptors might match between the target document and the sample page, but errors are not fatal to the search.", "In that system, documents accumulate votes based on matches of descriptors and the document with the highest vote count is returned as the target document.", "Of the descriptors disclosed by Hull, graphical descriptors looked to key features of the graphics on a page, whereas text descriptors looked to the pattern of letters or word lengths.", "However, the document management system of Hull uses an optical character recognition system to recognize characters from a digitized image of a page of a document or a sample page in order to form the descriptors for the page image.", "Since this is a computationally expensive operation, a more efficient method for generating descriptors from text is needed.", "SUMMARY OF THE INVENTION An improved document management system with high-speed retrieval by example is provided by virtue of the present invention.", "In one embodiment, the pages of documents scanned to be included in the storage of the document management system and the sample pages scanned as part of a retrieval process are described by descriptors that are extractable from the page with little computational effort.", "In a particular embodiment, bounding boxes are formed around connected components and the interbox spacings are measured.", "A histogram of interbox spacings is found and a threshold value is determined, with spacings less than the threshold deemed to be intercharacter spacing and the spacings larger than the threshold deemed to be interword spacings.", "The pattern of spacings is then translated into descriptors.", "In another embodiment, where interword spacing is rare, such as with Japanese text or other text which uses two alphabets with different densities, the histogram is of the pixel density of the bounding boxes instead of the interbox spacing.", "To address breaks in characters, overlapping bounding boxes may be combined into a single bounding box.", "If necessary, a language detection preprocessor could be used to detect the language of a document and apply the appropriate descriptor extraction.", "In a document where character spacing is regular, the intercharacter spacing can be used to further define the bounding boxes.", "The document management system, or just the query portion of the document management system might be tied into a copier.", "In such an embodiment, a user would need only to submit the sample page to the copier and the copier would retrieve the target document and print it.", "In alternate embodiments, the speech and text documents are used interchangeably as reference documents and large documents.", "The descriptors for a speech document can be either the pattern of phonemes per word or letters per word.", "In the former, a phoneme identifier is used and the phoneme identifier can identify interword silences.", "In the latter, a speech recognizer is used and the speech is converted to text which is then used as the basis for descriptor generation.", "A further understanding of the nature and advantages of the inventions herein may be realized by reference to the remaining portions of the specification and the attached drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a document management system according to the present invention.", "FIG. 2 is a block diagram of a descriptor generator which generates descriptors based on patterns of error character spacing.", "FIG. 3 is a block diagram of a descriptor generator which generates descriptors based on pixel density.", "FIG. 4(a) is an illustration of a document image.", "FIG. 4(b) is a closer view of a portion of the text area show in FIG. 4(A).", "FIG. 5 is a graphical representation of a histogram of intercharacter spacing.", "FIG. 6 is a image of a document containing Japanese characters.", "FIG. 7(a) is an image of a Japanese character.", "FIG. 7(b) is an image of the Japanese character shown in FIG. 7(a) with bounding boxes generated for portions of the Japanese character.", "FIG. 7(c) is an image of the Japanese character shown in FIGS. 7(a) and 7(b) with a single bounding box enclosing substantially all the character.", "FIG. 8 is a graphical representation of a histogram of pixel densities.", "FIG. 9 is a flow chart of a process of storing documents in a document database and retrieving documents by example.", "FIG. 10 a flow chart of a process of generating descriptors for a document.", "FIG. 11 is a block diagram of an alternate embodiment of a descriptor generator wherein the input documents are speech and the descriptors are based on the number of phonemes per word.", "FIG. 12 is a block diagram of an alternate embodiment of a descriptor generator wherein the input documents are speech and the descriptors are based on the number of letters per word.", "FIG. 13 is a flow chart of a process of storing reference speech passages and retrieving speech passages by example using target speech passages.", "FIG. 14 is a flow chart of a process of retrieving speech passages by example using both phoneme recognition and speech text recognition.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS The figures first show two embodiments with some elements in common.", "In one embodiment, intercharacter spacing is used to distinguish one document from another.", "The second embodiment uses character density to distinguish documents, followed by alternative embodiments where reference documents and/or target documents are in speech and/or text form.", "In general, these two systems work the same way and might even be used together.", "Before a document can be retrieved from a document database, the document database must be generated.", "To generate the database, documents are input.", "If the documents exist only on paper form, they are scanned to produce electronic, digitized representations of the documents.", "If the documents already exist in electronic form, the scanning step is not needed.", "For each document, a set of descriptors are generated.", "A descriptor is a pattern of metrics for part of the document.", "For example, if the metric is character spacing and the metric has one of two values (for example 1="interword space"", "and 0="intraword space"), a bit pattern can be generated for some or all of the document.", "Alternatively, the bit pattern is compressed into a string of word lengths.", "The bit pattern or word length pattern is then used as the descriptor.", "Typically, many descriptors are taken from a document and the descriptors may contain errors.", "However, if enough descriptors are taken, the errors will be filtered out, as explained in Hull.", "These descriptors are stored in an index and the document is stored in the document database.", "To retrieve a document by example, all or part of a target document is input to the system.", "The matching document is the document in the document database which has the most descriptors in common with the target document.", "Of course, the requirements for matching documents could be relaxed so that multiple matching documents are found, not just the most promising candidate.", "These multiple matching documents might then be presented to the user for manual selection of the correct document.", "The descriptors for the target document are obtained the same way the descriptors for the documents in the document database are obtained.", "Because the target document descriptors are obtained in the same way, the process of determining character bounds does not need to be correct, just consistent.", "The same is true for the process of measuring the metric.", "Thus, it is expected that some intraword spacings will be labelled as interword spacings, but since the same labelling occurs in the document database as with the target document, descriptors will match even though the labelling is not an accurate labelling of interword spacing.", "FIG. 1 is a block diagram of a document retrieval system 10, which includes an intake processor 12 for an input document 14, a document database 16, a descriptor database 18, a query processor 20 for processing a sample page 22 of a target document and for outputting the target document 24 which "matches"", "sample page 22.", "Both intake processor 12 and query processor 20 include a high-speed descriptor generator 40.", "Intake processor 12 accepts input documents, such as input document 14, and stores them into document database 16 while generating descriptors for the input document and storing the descriptors in descriptor database 18.", "Query processor 20 accepts sample page 22 and generates descriptors for the sample page using its descriptor generator 40.", "Of course, in some embodiments, only one descriptor generator is used and is shared between intake processor 12 and query processor 20.", "Query processor 20 is coupled to descriptor database 18 in order to apply descriptors to descriptor database 18 and have returned to it matches identifying documents in document database 16 which have descriptors in common with sample page 22.", "Query processor 20 is also coupled to document database 16 in order to retrieve documents based on the document identifiers obtained from the description database.", "Query processor 20 has an output from which a matching document (target document 24) is presented.", "In some embodiments, the output takes the form of a copier output which prints the target document.", "Query processor 20 might also include an interactive apparatus to allow a user to select from among more than one closely matching document (candidate documents).", "FIGS. 2 and 3 show descriptor generators in further detail.", "FIG. 2 is a block diagram of a descriptor generator 40A which generates descriptors based on word spacing (or approximations thereto).", "FIG. 3 is a block diagram of a descriptor generator 40B which generates descriptors based on pixel density.", "Referring to FIG. 2, descriptor generator 40A is shown comprising a segmenter 102, a box identifier 104, a histogram generator 106, a labeller 108A, and a descriptor writer 110A.", "Segmenter 102 inputs an image file 112 and outputs a segmented image 114.", "Box identifier 104 inputs this segmented image 114 and outputs box locations 116.", "Histogram generator 106 inputs these box locations 116 and outputs a histogram 118A of interbox spacing.", "Labeller 108A uses box locations 116 and histogram 118A as inputs to generate a set of word patterns 120, which is input to descriptor writer 110A, which outputs a set of descriptors 122 for image file 112.", "Image file 112 of FIG. 2 corresponds in FIG. 1 to an image of input document 14 or sample page 22.", "Segmenter 102 analyzes image file 112 and determines which areas of the image are text, figures, line art, or blank space.", "This allows down-stream elements of descriptor generator 40 to limit their work to the text areas of input image 112.", "Of course, as shown by Hull, the graphical areas of the image might also be used to generate descriptors.", "The text areas of image file 112 are stored as segmented image 114.", "Of course, depending on storage requirements and limitations, segmented image 114 could be limited to the text areas of image file 112, or segmented image 114 could be represented by nothing more than pointers to locations in the storage for image file 112.", "However the text areas are stored, box identifier 104 processes those text areas to locate bounding boxes around characters.", "FIG. 4(a) shows one such text area and FIG. 4(b) shows a subset of that text area (enlarged) with bounding boxes drawn around characters.", "There the bounding boxes are rectangles which surround regions of continuous black pixels.", "Only regions which are above a threshold size are considered;", "note that the dots of the "i"", "characters (402) and the periods (406) are ignored.", "Since these discrepancies between the bounding box and the actual bounds of the character are discrepancies in both input documents and target documents, they do not result in any errors.", "Breaks in characters due to poor copying might cause the character bounding boxes to exclude portions of boxes, such as with bounding boxes 408.", "While these discrepancies might cause errors, given the number of descriptors taken the target document and the matching document should still have more descriptors in common than the target document and a nonmatching document.", "In some embodiments, box identifier 104 performs an additional test on bounding boxes 116 to ensure that they are more or less lined up horizontally.", "This might be done by identifying the lines of text within the text areas, then identifying a baseline for each line of text and using the baseline as a guide for the location of bounding boxes.", "Once the bounding boxes are determined, their position on the image is noted and stored as box locations 116.", "Histogram generator 106 reads these box locations and calculates interbox spacing.", "If the distribution of interbox spacing is measured and a histogram is crested, two peaks should occur.", "An example of this is shown in histogram 118A of FIG. 2 which is represented in FIG. 5 graphically.", "This is a graph of pixel spacings between successive character bounding boxes for the text area shown in FIG. 4(a).", "Histogram 118A has two peaks, one for a spacing of around 5 pixels and one for a spacing of around 25 pixels.", "A minimum occurs between the two peaks, at around 16 pixels.", "Thus, for this data, a space of less than 16 pixels is probably an intraword space and a space of more than 16 pixels is probably an interword space.", "Labeller 108A uses that threshold to label each interbox space as either interword or intraword.", "Strictly speaking, labels are associated with the spaces between bounding boxes not the bounding boxes themselves.", "However, except for the last bounding box on each line of text, there is a one-to-one correspondence between bounding boxes and spaces, so the labels could just as easily be associated with the bounding boxes.", "In the latter case, if the label for a space is associated with the bounding box at the left of the space, then each bounding box might be characterized as bounding either a word-ending character or a non-word-ending character.", "Either way, the essential pattern of labels is the same.", "For example, if the text being processed is: "A sample sentence appears here.", """, "the pattern of spaces might be: "S-----S-------S------S---S"", "where '-'", "indicates an intraword space and 'S'", "indicates an interword space.", "Note that the '.", "'", "at the end of the sentence did not qualify for a bounding box and is therefore not considered, and an interword space following the end of each line is assumed.", "If instead, the labels '-'", "and 'S'", "were affixed to non-word-ending characters and word-ending characters, respectively, the same pattern would emerge.", "If expressed in binary, where '0'", "replaces '-'", "and '1'", "replaces 'S', the pattern would be: "1000001000000010000001000".", "This binary pattern could be compressed with run-length encoding to "16874"", "which is just the pattern of word lengths.", "The above example assumed that the bounding box locations were such that no intraword space was greater than the threshold and no interword space was less than the threshold.", "If there were, the pattern might be different, but it would be the same pattern both when the text was input and when the text was used for querying.", "In some embodiments, it might be desirable to fix the threshold ahead of time.", "If the threshold is fixed ahead of time, at say 16 pixels, then the histogram does not need to be created, as each space can be labelled as it is measured.", "It is not always desirable to fix the threshold, however.", "If the target document can be submitted with different scales or scanned at different resolutions, then the number of pixels at the minimum of the distribution of interbox spacing will vary and should be calculated each time for the particular image being used.", "Once word patterns 120 are generated by labeller 108A, they are formed into descriptors 122 by descriptor writer 110A.", "In one specific embodiment, a descriptor is the hashed concatenation of a set number of word lengths.", "These descriptors are then used as taught in the above description of FIG. 1. FIG. 3 is a block diagram of a descriptor generator 40B which is similar to descriptor generator 40A, except that descriptor generator 40B generates descriptors based on pixel density rather than interbox spacing.", "As with descriptor generator 40A, descriptor generator 40B includes a segmenter 102, a bounding box identifier 104, and the descriptor generator processes an input file 112 and generates segmented image 114 and box locations 116.", "Descriptor generator 40A also includes several elements which perform functions analogous to elements in descriptor generator 40B: a histogram generator 106B which generates a histogram 118B, a labeller 108B which generates density patterns instead of word patterns, and a descriptor writer 110B which writes descriptors based on density patterns rather than word patterns.", "Descriptor generator 40B also contains elements which have no analogy in descriptor generator 40A: a refiner 124 for refining box locations (optional), a pixel density counter 126 coupled to receive segmented image 114 and coupled to either refiner 124 (if used) or to receive box locations 116, and storage for pixel densities 128.", "In descriptor generator 40B labeller 108B is coupled to receive box locations 116, pixel densities 128 and histogram 118B.", "As with descriptor generator 40A, if a fixed threshold is used, histogram 118B is not needed.", "However, in contrast with descriptor generator 40A, the operation of descriptor generator 40B might be independent of the scales and scanning resolutions used, since the threshold is a pixel density not a spacing.", "In operation, segmenter 102 reads the input file 112 and segments it into text and other areas.", "The segmented image 114 is read by box identifier 104 to generate a list of box locations 116.", "An example of an image which might be contained in input file 112 or segmented image 114 is shown in FIG. 6 with the bounding boxes added as indicated by box locations 116.", "Although FIG. 6 shows an image of Japanese characters, non-Japanese text with characters having a variable pixel density can also be processed by this apparatus.", "With Japanese characters, the distribution of pixel densities should have two peaks, one representing Japanese Kanji characters and the other representing Japanese Kana characters.", "The Kanji characters were originally derived from the Chinese ideograms and tend to have more strokes, while the Kana characters, which are from a syllabic alphabet, have fewer strokes.", "Unlike the 26-letter Latin alphabet, Japanese characters are often made up of unconnected strokes, and a single character might be boxed by multiple bounding boxes.", "For example, FIG. 7 shows one Japanese character being bounded.", "FIG. 7(a) shows the character before the bounding boxes are generated and FIG. 7(b) shows two bounding boxes 704, 706 overlaid on three unconnected elements of the character.", "Stroke which do not have enough pixels to qualify as their own elements are not bounded.", "The optional refiner 124 refines the bounding box process by joining overlapping bounding boxes on the assumption that they cover elements of the same character.", "Refiner 124 locates a rectangle which encloses all of the overlapping boxes.", "Thus, as shown in FIG. 7(c), the bounding box 710 would result and would replace boxes 704 and 706.", "Whether or not refiner 124 is used, pixel density counter 126 counts the number of pixels in each bounding box and the number of black pixels.", "As should be apparent, the same effect can be had by counting the white pixels, and if the characters are not black, the count is of the number of pixels making up the character, whatever color or colors it might be.", "The pixel density is then just the number of black pixels divided by the total number of pixels in the bounding box (normalized density).", "Alternatively, the bounding boxes can be assumed to all be the same size, or can be forced to be the same size, thus eliminating the need for the normalization step.", "The pixel densities are stored in storage for pixel densities 128 and used by histogram generator 106B to generate histogram 118B.", "A graphical representation of an example histogram 118B is shown in FIG. 8. In FIG. 8, the histogram shows the distribution of pixels without normalization.", "The denser Kanji characters are clustered together in the range of 250 to 450 black pixels, and a threshold of 252 pixels separates the peaks well.", "It should be noted that some Kanji characters may fall below the threshold and some Kana characters may fall above it.", "However, so long as the measurement is consistent, a document will have the same descriptors when input as when used as a target document.", "The threshold can be calculated either by histogram generator 106B or labeller 108B.", "One way to calculate a threshold is shown by N. Otsu, "A Threshold Selection Method from Gray Level Histograms,"", "IEEE Trans.", "Systems man and Cybernetics, Vol. smc-9, #1, January, 1979, pp. 63-66.", "In either case, labeller 108B uses the threshold while reading pixel densities 128 (and box locations 116, if needed for normalization) to assign one of two labels to the character.", "The two labels might be Kanji/Kana, high/low density (more accurate), or just '1'/'0'.", "In any case, the labels assigned to consecutive bounding boxes form patterns which are stored as density patterns 130.", "Density patterns 130 are used by descriptor writer 110B to generate descriptors 122 much the same way word patterns are used in descriptor generator 40A (see FIG. 2).", "Various apparatus for storing and retrieving documents by example have been described.", "FIGS. 9-10 are flow charts of a process for document retrieval by example, such as might be performed using the above-described apparatus.", "FIG. 9 is a flow chart describing a process of storing documents in a document database and retrieving documents matching a target document by the example provided by the target document.", "At step S1, documents are input into a document storage and retrieval system.", "At step S2, descriptors are generated for the documents being input.", "Where text is used as the basis for descriptors, the word spacing determines the descriptors.", "With speech (see FIGS. 11-12), the patterns of phonemes, the patterns of word lengths, or both are used, where the word lengths are determined using speech recognition to first convert the speech to text.", "In step S3, following the generation of the descriptors and the input of the documents, the documents are stored in a database and the descriptors are stored in a descriptor database with links to the documents stored in the document database.", "The next step (S4), is the beginning of a loop which is executed for each target document to be retrieved.", "In step S4, the target document is input.", "As explained above, the input need not be the entire target document nor even an entire page of the target document.", "Next, in step S5, descriptors are generated for the input target document.", "This step is similar to step S2.", "Again, if the input document is speech, the descriptors can be based on phoneme patterns as well as word lengths.", "Next, in step S6, the descriptors generated from the target document are used as indexes into the descriptor database, which yields a list of potentially matching documents.", "In step S7, the matching documents are retrieved from the document database.", "If more target documents are to be retrieved, the process continues at step S4, otherwise the process completes.", "FIG. 10 is a detailed flow chart describing the process of generating descriptors from a document where the document is text or text/graphics.", "This description applies to input documents whether they are documents initially input to the document database or are portions of target documents.", "At step S10, the image of the document for which descriptors are to be generated is input to a descriptor generator.", "The input image is then segmented into text and non-text regions (S 1 ).", "The descriptor generator analyzes the text segments to find bounding boxes for the characters in text regions (S12).", "Once the bounding boxes are identified, the descriptor generator generates a histogram of interbox spacings (S13).", "From this histogram, the descriptor generator determines a threshold between two peaks of the histogram (S14).", "The descriptor generator then reviews the text region, or at least the pattern of interbox spacing, to label each interbox spacing based on whether it is less than or greater than the threshold determined in step S14 (S15).", "The descriptor generator then generates descriptors from runs of interbox spacing (S16).", "The flow chart of FIG. 10 also applies to the process of generating descriptors from pixel density patterns.", "The difference is that in step S13, the histogram generated is a histogram of pixel densities.", "Once the histogram is generated, the processes of steps S14, S15 and S16 are performed in the same manner as the above example where the histogram is the histogram of interbox spacing.", "FIGS. 11-12 are block diagrams of descriptor generators for generating descriptors from speech documents.", "These speech documents can be either reference documents or target documents.", "Examples of speech documents are digitized audio of famous speeches, lectures, doctor's comments on patients, pronunciations and the like, however any speech can be used.", "FIG. 11 is a block diagram of a descriptor generator 40C, where the descriptors are based on phonemes.", "Descriptor generator 40C includes a phoneme recognizer 802, a "space"", "recognizer", a labeller 108C and a descriptor writer 110C.", "Phoneme recognizer 802 reads an input speech document 806 and generates phoneme patterns 808.", "The phoneme patterns 808 represent the speech, indicating which sounds were emitted and where silences occur.", "These phoneme patterns 808 are fed to "space"", "recognizer 804, which isolates the positions of the silence "phonemes"", "in the recognized speech and passes them to labeller 108C.", "Labeller 108C and descriptor writer 110C operate like their counterparts in descriptor generators 40A, 40B.", "The output of labeller 108C is the patterns of "spaces"", "and words.", "For example, if speech file 806 contained the spoken phrase "the large car", phoneme recognizer 802 might recognize the phrase as being eleven phonemes and identify the particular eleven phonemes.", ""Space"", "recognizer 804 would then identify that the phonemes were two spoken phonemes, a silence phoneme, four spoken phonemes, a silence phoneme, and three spoken phonemes.", "Labeller 108C would then label the silence phonemes as "spaces", resulting in the pattern 2-S-4-S-3, which descriptor writer 110C would write out as "2-4-3".", "Even where all the reference documents are speech and the only descriptors are phoneme-based descriptors, a text document could still be used as a target document.", "The text of the target document is fed through a phoneme generator which generates phonemes from text, and the phonemes would be used to generate descriptors.", "Of course, with a complex language such as English, an automatic phoneme generator will make errors.", "However, since the descriptors are redundant, the correct document will generally be found even in the presence of errors.", "Were both the input document and the reference documents are speech and are described by phoneme patterns, the errors are even less significant if the same phoneme generator is used for both the reference documents and the input documents, since an error common to both does not make a document harder to find.", "The same is true for text reference documents and speech input documents, or some combination of each.", "Since phonemes are the unit of speech, the embodiment shown in FIG. 11 is not specific to a particular language.", "FIG. 12 is a block diagram of a descriptor generator 40D, where the descriptors are based on word length, but are generated for speech documents.", "Descriptor generator 40D is shown comprising a speech recognizer 902 which also reads a speech document/file 806 as with descriptor generator 40C, but instead of outputting phonemes, speech recognizer 902 outputs the text 906 of the spoken words.", "Text 906 is processed by space labeller 904, which marks the locations of the spaces in text 906, resulting in word patterns 120, as are described above in connection with FIG. 2. As also described in connection with FIG. 2, word patterns 120 are used by descriptor writer 11OA to generate descriptors 122.", "Continuing the example used in connection with FIG. 11, if speech file 806 contained the spoken phrase "the large car", speech recognizer 802 might recognize the phrase as being the text: "the large car", and space labeller 904 would output the word pattern "---S-----S---"", "which would result in the descriptor "3-5-3".", "FIGS. 13-14 are flow charts illustrating a process of matching speech documents (passages).", "The process shown in FIG. 13 is similar to the process shown in FIG. 9, except that the process of FIG. 9 covers all combinations of speech and text input and target documents, whereas the processes of FIGS. 13 and 14 deal only with speech passages.", "Of course, text passages could be converted to "quasi-speech"", "in the form of phoneme patterns so that documents might be matched on the basis of "sound-alike"", "matching, but since only the number of phonemes per word is used in descriptor generation, "sound-alike"", "matching is not needed.", "In fact, all that is needed is a dictionary of words which includes the number of phonemes for each word, thus serving as a simple look up table.", "In the process shown in FIG. 13, speech passages are input (S1'), descriptors are generated for them (S2') and the passages and descriptors are stored with links between them (S3').", "To retrieve a passage by matching, the target passage is input (S4'), descriptors are generated (S5'), the descriptors are matched (S6') to descriptors in the databases created in step S3', and the matching passages are retrieved (S7').", "If more target passages exist, steps S4'", "through S7'", "are repeated for those passages.", "The process shown in FIG. 14 uses both phoneme descriptors and speech text descriptors.", "The speech text descriptors are essentially the same as the word length descriptors described above--they are generated from the text resulting from speech recognition of the passages.", "The reference passages are input (S20) and phoneme descriptors are generated (S21) along with text descriptors (S22).", "These steps can be performed in parallel, but need not be.", "Next, the phoneme descriptors are stored (S23) and the text descriptors are stored (S24) and the passages are stored (S25) with links between passages and descriptors.", "To retrieve a passage, the target passage is input (S26), and phoneme descriptors are generated (S27) and text descriptors are generated (S28).", "Again, these steps can occur in series or parallel.", "Next, the phoneme descriptors are matched to the stored phoneme descriptors (S29) and the text descriptors are matched to the stored text descriptors (S30) to provide two lists of passages ranked according to how well they matched.", "The two lists are then merged into a single ranging (S31).", "It is well known in the art of pattern matching to combine independently generated rankings.", "See, for example, T. K. Ho, J. J. Hull, S. N. Srihari, "Decision Combination in Multiple Classification Systems", IEEE Transactions on Pattern Analysis and Machine Intelligence, V[.", "].16, No. 1, January 1994, pp. 66-75.", "The above description is illustrative and not restrictive.", "Many variations of the invention will become apparent to those of skill in the art upon review of this disclosure.", "Merely by way of example, if the distribution of a metric related to characters has more than two peaks, the distribution might be divided into more than two ranges and the labeller in that case would label each character with more than just a binary label.", "Also, the text documents can be stored in a variety of formats, such as ASCII files, page description language files such as Postscript™ files, or word processing files such as WordPerfect™ or Microsoft Word™ files.", "The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The purpose of this invention is a filtering cell and a corresponding filter. It has many applications in electronics, particularly in the manufacture of rejection, low-pass and high-pass filters. This filtering technique can be applied, especially, in video communications cable networks when certain television channels must be filtered. The invention applies to all filters with one or more cells including a resonant circuit composed of at least one first type of inductive or capacitive reactance (this reactance being either an inductance or a capacitor) and at least one second type of reactance opposed to the first, capacitive or inductive (therefore consisting of a capacitor or an inductance). Such cells may be laid out in series or parallel, with π, T or trellis-shaped structures etc. However to simplify the description that follows, we shall limit ourselves to resonant-parallel-type cells, mounted in series with no limitation on the scope of the invention. DESCRIPTION OF THE RELATED ART A resonant-parallel-type filtering cell according to the prior state of the art is shown in FIG. 1, which is attached. This cell includes a capacitor C and an inductance L forming a resonant circuit at the frequency Fo=1/2π√L C. One input E is connected to an impedance generator G with an output R G and one output S to a load R. The voltages at input E and output S are marked respectively Ve and Vs. The theoretical response of such a filter is shown in FIG. 2A. The axis of the ordinate contains the attenuation A, i.e., the ratio Vs/Ve, measured in decibels (this ratio is negative). The axis of the abscissa corresponds to the frequency F. At the frequency Fo, the attenuation is, in principle, infinitely great. In reality, the components used to make such a cell are not perfect, and the inductance, in particular, has a resistance that is far from negligible. The damping that results has the effect of substantially changing the attenuation curve, which then takes the form shown in FIG. 2B. There is still a frequency where the attenuation is maximum (in absolute value), but this attenuation has a finite value (for example 20 or 30 dB). It can prove insufficient in practice when it is a question of effective rejection or obtaining a clean cut. We know how to correct a parallel cell LC mounted in series by splitting the capacitor in two and connecting a resistor connected to the mass to the midpoint found this way. The rejection obtained is great, but the losses above and beyond the rejected frequency are great. Moreover, the match is not satisfactory. FIGS. 3A to 3F provide details on these questions. FIG. 3A, first of all, shows the attenuation of a particular uncorrected cell LC where the attenuation is put on the ordinate and the frequency on the abscissa. At the rejection frequency, the attenuation is -18 dB. By correcting the cell with a simple resistor, one obtains the values in FIG. 3B. The attenuation to rejection is -28 dB. FIG. 3C shows more precisely the attenuation of the rejection frequency for the uncorrected cell LC. For example, one obtains 0.2 dB to 800 MHz and 2 dB to 600 MHz FIG. 3D likewise shows this attenuation for the same cell corrected with a resistor. An attenuation of 1.2 dB to 800 MHz and 2.5 dB to 600 MHz is obtained. FIGS. 3E and 3F show the mismatching of the cell respectively uncorrected (-13 dB to 800 MHz) and corrected with a resistor (-13 dB to 800 MHz) SUMMARY OF THE INVENTION This invention has as its purpose to eliminate these drawbacks and is aimed at simply correcting the existing filters to obtain both greater attenuation at the resonance frequency Fo and better adaptation at low frequencies. In other words, the slope of the line joining the point of the attenuation curve at the frequency Fo and the point of that same curve at a certain lower frequency is increased substantially in relation to the prior state of the art. After theoretical and experimental work on filters, the inventors found that the defect in quality of the inductance or the capacitor was not an insurmountable handicap, but could be corrected if a capacitor with an appropriate value is put with the inductance or an inductance with an appropriate value is put with the capacitor. In other words, the invention proposes to correct the quality coefficient of the resonant circuit and to do so either by acting on the inductance or on the capacitor or both. With the cell thus corrected, the inventors showed that attenuation at the resonance frequency was substantially increased. It must be observed that the frequency corresponding to maximum attenuation is displaced slightly by adding the correction reactance. If need be, this effect can always be corrected by modifying the value of the reactances of the cell to put the frequency back at the value before correction. For example, in the case of a correction of the inductance, it will suffice to increase the value of the main capacitor by a fraction of the capacity of the correction capacitor. The advancement brought by the invention is accompanied by another advantage, which is to perfect the matching of the impedance of the filtering cell. After correction, the part of the energy reflected by the cell falls to a very low value (-20 dB for example) for frequencies below the resonance frequency. In other words, the reflection coefficient is quasi-zero and the stationary wave rate near unity. One will note that these high performances are obtained despite the mediocre quality of the inductance or the capacitor. The filtering cell in the invention can thus be accommodated to inexpensive components. Moreover, as will be better understood later on, the invention lends itself particularly to the micro-ribbon technology where inductances can have a mediocre quality coefficient on certain substrates, which has a tendency to downgrade the performance of the filters. To be precise, the purpose of the invention is therefore a filtering cell with a resonant circuit composed of at least one first reactance of a first type (inductive or capacitive) and at least one second reactance of a second type opposite the first (capacitive or inductive), with this cell characterized by the fact that at least one of the two reactances is separated into two parts placed in series with a midpoint and includes a correction reactance connected to said midpoint, and this correction reactance is the opposite type reactance on which the correction was made, (capacitive if the reactance on which one is acting is inductive type and inductive if the reactance on which one is acting is capacitive type), and this correction reactance must have an appropriate quality coefficient. Two methods of execution are provided, depending on whether one corrects the inductance (with a capacitor) or the capacitor (with an inductance). Although any type of cell may be used, the resonant-parallel type cell, mounted in series, seems to lend itself particularly well to the application in the invention. According to the invention, the correction capacitor may be no longer localized, but may be distributed. This invention also has as its purpose a filter with a large number of filtering cells, and this filter is characterized by the fact that at least one of these cells conforms to any one of the cells just defined. BRIEF DESCRIPTION OF THE DRAWINGS In any case, the characteristics and advantages of the invention will be better seen in light of the description that follows. This description covers examples of execution given for explanatory purposes which are in no way limiting, and it refers to the attached drawings where: FIG. 1, already described, shows a rejection filter cell according to the prior state of the art, FIGS. 2A and 2B, already described, show the theoretical attenuation and the attenuation actually obtained with a filter of the prior state of the art in FIG. 1, FIGS. 3A to 3F, already described, show performance curves for cells of the prior state of the art with a correction resistor, FIG. 4 shows a filter according to the invention in a variation with a resonant-parallel-type cell, mounted in series, with correction on the inductance, FIG. 5 shows the attenuation obtained with a filter in FIG. 4, FIG. 6 shows a practical case of execution of a rejection filter according to the prior state of the art, FIG. 7 shows a practical case of execution of a rejection filter according to the invention, with correction on the inductance, FIGS. 8 and 9 show the rejection of the filter in FIG. 6, FIGS. 10 and 11 show the rejection of the filter in FIG. 7, FIG. 12 illustrates a cell in π, corrected according to the invention, FIG. 13 shows the attenuation obtained with the preceding filter, FIG. 14 shows a rejection filter with three cells according to the invention, FIG. 15 illustrates a method of execution of a micro-ribbon cell, FIG. 16 shows a four-cell folded micro-ribbon filter, FIG. 17 shows a filter according to the invention in a mode of execution where the correction is carried out by an inductance connected between two capacitors, FIGS. 18A, 18B, 18C illustrate the performance obtained by the filter in the preceding figure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 4 shows a filtering cell according to the invention, in the special case of a resonant-parallel cell mounted in series and in a method of execution corresponding to a correction on the inductance. As already described for FIG. 1, this cell has a capacitor C and an inductance with the value L, but the latter is shared by two inductances with the value L/2 and a midpoint M. A correction capacitor Cc is connected between the midpoint M of the inductance and the ground. This capacitor has a resistor Rc either intrinsically or via a resistor intentionally connected in parallel. The value of the capacitance Cc is equal at L/R 2 , where L is the sum of the two halves of the inductance (L/2+L/2) and R is the value of the load. As for the quality coefficient RcCcw, it is equal to that of the inductance or Lw/r, where r is the resistance of the inductance and W is the angular pulsation 2πF, where F is the frequency. The resistance Rc is therefore equal to L/rCc. The attenuation obtained under these conditions is shown in FIG. 5. At the frequency Fo, the attenuation is substantially greater than in the prior state of the art (see FIG. 3). Moreover after the frequency Fo, a second pole or point of rejection appears. Generally, these changes are not important where it is a question of cutting the frequency Fo or obtaining a low-pass filter. The curves in FIGS. 6 to 11 make it possible better to judge the improvements made by the invention. First of all, FIG. 6 corresponds to a filter of the prior state of the art, with a 2 μH inductance and a 1 nF capacitor. FIG. 8 shows the performance of this filter. The axis of the abscissa shows the frequency, which ranges from 2 MHz to 5.2 MHz. The central frequency is equal to 3.6 MHz. The axis of the ordinate shows the attenuation on a scale divided into 5 dB sections. Curve A corresponds to the attenuation measured. At best, it is equal to -18 dB for Fo=3.6 MHz. Curve B corresponds to the mismatch which is -9 dB at the start of the range. The performance of the same filter corrected with a capacitor with a value Cc=820 pF with Rc=330 Ω (see FIG. 7) is shown in FIG. 10 on the same scale: the attenuation A' falls to -40 dB and the mismatch B' to -20 dB. Curves 9 and 11 make it possible to compare the filters with discrete components according to the prior state of the art (FIG. 6) and according to the invention (FIG. 7). In both cases the axis of the abscissa extends from 1 MHz to 18 MHz. The axis of the ordinate shows an attenuation with 10 dB per division. The filter of the prior state of the art has an attenuation of around 18 dB (FIG. 9), while the same filter corrected according to the invention, by adding a capacitor, has its attenuation fall to -50 dB, which represents a considerable improvement, considering the modesty of the change. The invention is not limited to resonance-parallel-type cells, mounted in series, but extends to other types like cells in II an example of which is given in FIG. 12. Such a cell includes three capacitors C1, C2. C3 and, according to the invention, one inductance formed from two semi-inductances L/2, with a correction capacitor Cc with a parallel resistor Rc. The corresponding attenuation curve is shown in FIG. 13 in a continuous line; the part with dashes shows the curve obtained without correction, according to the prior state of the art. The invention is not limited to a single filtering cell, either, but encompasses any filter with several cells, at least one of which is corrected as just explained. FIG. 14 shows a filter with three filtering cells CF1, CF2, CF3, all three conforming to the invention, with three correction capacitors Cc1, Cc2. Cc3. The rejection frequencies may be completely different. The quality coefficients of the capacitors Cc1 , . . . , must be identical in value to the value of the quality coefficients of the associated inductances. Although this initial version of the invention may be made with discrete components, it is more convenient, when the working frequency range reaches and exceeds a gigahertz, to achieve inductance of the filter in the form of a micro-ribbon conductor. The invention lends itself particularly well to this technology. Indeed, in this case, as shown in FIG. 15, a filtering cell according to the invention can include two micro-ribbons 10 and 12 deposited on an insulating substrate 14. These two micro-ribbons, which can be any geometric shape, consist of two semi-inductances and also include a micro-ribbon 16. This micro-ribbon 16 forms, with a mass plan 18 deposited on the other side of the substrate, the correction capacitor. A discrete capacitor 19 completes the unit. One can therefore see that in this technology, the correction capacitor 16 is integrated quite naturally between the two semi-inductances 10, 12. One need only regulate the width of the micro-ribbon 16 to obtain the appropriate capacitance Cc. Several cells of this type can be placed end to end on the same substrate. One may also fold the substrate as shown in FIG. 16. A substrate 20 consists of two insulating plates 21 and 22 separated by a conductive plane 23. On the front of the plate 21, there are two filtering cells similar to the one in FIG. 15, or CF1 and CF2. A metallized hole 25 (insulated from the plane 23) makes it possible to establish an electrical connection with the back of the plate 22, which has two cells like CF1 and CF2 (not visible in the Figure). The input and output of the filter is handled by the connectors 30 and 32, respectively. The different methods of execution which have just been described correspond to a case where correction is carried out on the inductance of the resonant circuit by an ad hoc quality coefficient capacitor. But the invention covers a case where correction is carried out on the capacitor of the resonant circuit with an inductance associated with a resistor. The corresponding cell is illustrated in FIG. 17. The capacitor is split into two capacitors with a value of 2c connected in series with a midpoint M. Between this point and the mass, an inductance with a value Lc and a correction resistor Rc in series are connected. Moreover, the main inductance L is associated with a resistor R1, and R1 is connected to the quality factor L. The other media are identical to those in FIG. 4 FIGS. 18A, B, C illustrate the performance obtained. The results shown should be compared with the results illustrated in FIGS. 3B, 3D and 3F, respectively, compared to a cell of the prior state of the art. One can see, particularly in FIG. 18A, an attenuation of -32 dB at the rejection frequency (compared with -28 dB); in FIG. 18B losses from 0.4 dB to 800 MHz and from 1.5 dB to 600 MHz (compared to 1.2 and 2.5 dB, respectively); and lastly, in FIG. 18C a mismatch of -26 dB to 800 MHz (compared to -13 dB). The theoretical and experimental work of the inventors has shown that there is a wide choice of values for the correction elements Lc and Rc The maximum value of Lc is 1/2R 1 C 2 w o 3 and in this case the correction resistance Rc is equal to L c w o . Then, there must be ##EQU1## If a value of Lc is chosen that is lower than the maximum value, then Rc can have two values: ##EQU2## with K=R1C 2 w o 2 and A= 1-4K 2 Lc 2 w o 2 and it is still necessary to require ##EQU3## In these equations, L and R1 are the inductance of the resonant circuit with its associated interference resistor which determines the quality coefficient, C is the capacitance of the capacitor of the resonant circuit, w o is the resonance pulsation chosen with w o =2πFo, where Fo is the resonance frequency.
A filtering cell including a resonant circuit having an inductor and capacitor connected in parallel, the inductor being separated into two identical inductors which are connected in series with a midpoint therebetween. A second capacitor is connected at the midpoint and has a quality factor substantially equal to a quality factor of the first inductor, resulting in attenuation at the resonant frequency. Each of the inductors and capacitors are formed by micro-ribbon technology.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The purpose of this invention is a filtering cell and a corresponding filter.", "It has many applications in electronics, particularly in the manufacture of rejection, low-pass and high-pass filters.", "This filtering technique can be applied, especially, in video communications cable networks when certain television channels must be filtered.", "The invention applies to all filters with one or more cells including a resonant circuit composed of at least one first type of inductive or capacitive reactance (this reactance being either an inductance or a capacitor) and at least one second type of reactance opposed to the first, capacitive or inductive (therefore consisting of a capacitor or an inductance).", "Such cells may be laid out in series or parallel, with π, T or trellis-shaped structures etc.", "However to simplify the description that follows, we shall limit ourselves to resonant-parallel-type cells, mounted in series with no limitation on the scope of the invention.", "DESCRIPTION OF THE RELATED ART A resonant-parallel-type filtering cell according to the prior state of the art is shown in FIG. 1, which is attached.", "This cell includes a capacitor C and an inductance L forming a resonant circuit at the frequency Fo=1/2π√L C. One input E is connected to an impedance generator G with an output R G and one output S to a load R. The voltages at input E and output S are marked respectively Ve and Vs.", "The theoretical response of such a filter is shown in FIG. 2A.", "The axis of the ordinate contains the attenuation A, i.e., the ratio Vs/Ve, measured in decibels (this ratio is negative).", "The axis of the abscissa corresponds to the frequency F. At the frequency Fo, the attenuation is, in principle, infinitely great.", "In reality, the components used to make such a cell are not perfect, and the inductance, in particular, has a resistance that is far from negligible.", "The damping that results has the effect of substantially changing the attenuation curve, which then takes the form shown in FIG. 2B.", "There is still a frequency where the attenuation is maximum (in absolute value), but this attenuation has a finite value (for example 20 or 30 dB).", "It can prove insufficient in practice when it is a question of effective rejection or obtaining a clean cut.", "We know how to correct a parallel cell LC mounted in series by splitting the capacitor in two and connecting a resistor connected to the mass to the midpoint found this way.", "The rejection obtained is great, but the losses above and beyond the rejected frequency are great.", "Moreover, the match is not satisfactory.", "FIGS. 3A to 3F provide details on these questions.", "FIG. 3A, first of all, shows the attenuation of a particular uncorrected cell LC where the attenuation is put on the ordinate and the frequency on the abscissa.", "At the rejection frequency, the attenuation is -18 dB.", "By correcting the cell with a simple resistor, one obtains the values in FIG. 3B.", "The attenuation to rejection is -28 dB.", "FIG. 3C shows more precisely the attenuation of the rejection frequency for the uncorrected cell LC.", "For example, one obtains 0.2 dB to 800 MHz and 2 dB to 600 MHz FIG. 3D likewise shows this attenuation for the same cell corrected with a resistor.", "An attenuation of 1.2 dB to 800 MHz and 2.5 dB to 600 MHz is obtained.", "FIGS. 3E and 3F show the mismatching of the cell respectively uncorrected (-13 dB to 800 MHz) and corrected with a resistor (-13 dB to 800 MHz) SUMMARY OF THE INVENTION This invention has as its purpose to eliminate these drawbacks and is aimed at simply correcting the existing filters to obtain both greater attenuation at the resonance frequency Fo and better adaptation at low frequencies.", "In other words, the slope of the line joining the point of the attenuation curve at the frequency Fo and the point of that same curve at a certain lower frequency is increased substantially in relation to the prior state of the art.", "After theoretical and experimental work on filters, the inventors found that the defect in quality of the inductance or the capacitor was not an insurmountable handicap, but could be corrected if a capacitor with an appropriate value is put with the inductance or an inductance with an appropriate value is put with the capacitor.", "In other words, the invention proposes to correct the quality coefficient of the resonant circuit and to do so either by acting on the inductance or on the capacitor or both.", "With the cell thus corrected, the inventors showed that attenuation at the resonance frequency was substantially increased.", "It must be observed that the frequency corresponding to maximum attenuation is displaced slightly by adding the correction reactance.", "If need be, this effect can always be corrected by modifying the value of the reactances of the cell to put the frequency back at the value before correction.", "For example, in the case of a correction of the inductance, it will suffice to increase the value of the main capacitor by a fraction of the capacity of the correction capacitor.", "The advancement brought by the invention is accompanied by another advantage, which is to perfect the matching of the impedance of the filtering cell.", "After correction, the part of the energy reflected by the cell falls to a very low value (-20 dB for example) for frequencies below the resonance frequency.", "In other words, the reflection coefficient is quasi-zero and the stationary wave rate near unity.", "One will note that these high performances are obtained despite the mediocre quality of the inductance or the capacitor.", "The filtering cell in the invention can thus be accommodated to inexpensive components.", "Moreover, as will be better understood later on, the invention lends itself particularly to the micro-ribbon technology where inductances can have a mediocre quality coefficient on certain substrates, which has a tendency to downgrade the performance of the filters.", "To be precise, the purpose of the invention is therefore a filtering cell with a resonant circuit composed of at least one first reactance of a first type (inductive or capacitive) and at least one second reactance of a second type opposite the first (capacitive or inductive), with this cell characterized by the fact that at least one of the two reactances is separated into two parts placed in series with a midpoint and includes a correction reactance connected to said midpoint, and this correction reactance is the opposite type reactance on which the correction was made, (capacitive if the reactance on which one is acting is inductive type and inductive if the reactance on which one is acting is capacitive type), and this correction reactance must have an appropriate quality coefficient.", "Two methods of execution are provided, depending on whether one corrects the inductance (with a capacitor) or the capacitor (with an inductance).", "Although any type of cell may be used, the resonant-parallel type cell, mounted in series, seems to lend itself particularly well to the application in the invention.", "According to the invention, the correction capacitor may be no longer localized, but may be distributed.", "This invention also has as its purpose a filter with a large number of filtering cells, and this filter is characterized by the fact that at least one of these cells conforms to any one of the cells just defined.", "BRIEF DESCRIPTION OF THE DRAWINGS In any case, the characteristics and advantages of the invention will be better seen in light of the description that follows.", "This description covers examples of execution given for explanatory purposes which are in no way limiting, and it refers to the attached drawings where: FIG. 1, already described, shows a rejection filter cell according to the prior state of the art, FIGS. 2A and 2B, already described, show the theoretical attenuation and the attenuation actually obtained with a filter of the prior state of the art in FIG. 1, FIGS. 3A to 3F, already described, show performance curves for cells of the prior state of the art with a correction resistor, FIG. 4 shows a filter according to the invention in a variation with a resonant-parallel-type cell, mounted in series, with correction on the inductance, FIG. 5 shows the attenuation obtained with a filter in FIG. 4, FIG. 6 shows a practical case of execution of a rejection filter according to the prior state of the art, FIG. 7 shows a practical case of execution of a rejection filter according to the invention, with correction on the inductance, FIGS. 8 and 9 show the rejection of the filter in FIG. 6, FIGS. 10 and 11 show the rejection of the filter in FIG. 7, FIG. 12 illustrates a cell in π, corrected according to the invention, FIG. 13 shows the attenuation obtained with the preceding filter, FIG. 14 shows a rejection filter with three cells according to the invention, FIG. 15 illustrates a method of execution of a micro-ribbon cell, FIG. 16 shows a four-cell folded micro-ribbon filter, FIG. 17 shows a filter according to the invention in a mode of execution where the correction is carried out by an inductance connected between two capacitors, FIGS. 18A, 18B, 18C illustrate the performance obtained by the filter in the preceding figure.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 4 shows a filtering cell according to the invention, in the special case of a resonant-parallel cell mounted in series and in a method of execution corresponding to a correction on the inductance.", "As already described for FIG. 1, this cell has a capacitor C and an inductance with the value L, but the latter is shared by two inductances with the value L/2 and a midpoint M. A correction capacitor Cc is connected between the midpoint M of the inductance and the ground.", "This capacitor has a resistor Rc either intrinsically or via a resistor intentionally connected in parallel.", "The value of the capacitance Cc is equal at L/R 2 , where L is the sum of the two halves of the inductance (L/2+L/2) and R is the value of the load.", "As for the quality coefficient RcCcw, it is equal to that of the inductance or Lw/r, where r is the resistance of the inductance and W is the angular pulsation 2πF, where F is the frequency.", "The resistance Rc is therefore equal to L/rCc.", "The attenuation obtained under these conditions is shown in FIG. 5. At the frequency Fo, the attenuation is substantially greater than in the prior state of the art (see FIG. 3).", "Moreover after the frequency Fo, a second pole or point of rejection appears.", "Generally, these changes are not important where it is a question of cutting the frequency Fo or obtaining a low-pass filter.", "The curves in FIGS. 6 to 11 make it possible better to judge the improvements made by the invention.", "First of all, FIG. 6 corresponds to a filter of the prior state of the art, with a 2 μH inductance and a 1 nF capacitor.", "FIG. 8 shows the performance of this filter.", "The axis of the abscissa shows the frequency, which ranges from 2 MHz to 5.2 MHz.", "The central frequency is equal to 3.6 MHz.", "The axis of the ordinate shows the attenuation on a scale divided into 5 dB sections.", "Curve A corresponds to the attenuation measured.", "At best, it is equal to -18 dB for Fo=3.6 MHz.", "Curve B corresponds to the mismatch which is -9 dB at the start of the range.", "The performance of the same filter corrected with a capacitor with a value Cc=820 pF with Rc=330 Ω (see FIG. 7) is shown in FIG. 10 on the same scale: the attenuation A'", "falls to -40 dB and the mismatch B'", "to -20 dB.", "Curves 9 and 11 make it possible to compare the filters with discrete components according to the prior state of the art (FIG.", "6) and according to the invention (FIG.", "7).", "In both cases the axis of the abscissa extends from 1 MHz to 18 MHz.", "The axis of the ordinate shows an attenuation with 10 dB per division.", "The filter of the prior state of the art has an attenuation of around 18 dB (FIG.", "9), while the same filter corrected according to the invention, by adding a capacitor, has its attenuation fall to -50 dB, which represents a considerable improvement, considering the modesty of the change.", "The invention is not limited to resonance-parallel-type cells, mounted in series, but extends to other types like cells in II an example of which is given in FIG. 12.", "Such a cell includes three capacitors C1, C2.", "C3 and, according to the invention, one inductance formed from two semi-inductances L/2, with a correction capacitor Cc with a parallel resistor Rc.", "The corresponding attenuation curve is shown in FIG. 13 in a continuous line;", "the part with dashes shows the curve obtained without correction, according to the prior state of the art.", "The invention is not limited to a single filtering cell, either, but encompasses any filter with several cells, at least one of which is corrected as just explained.", "FIG. 14 shows a filter with three filtering cells CF1, CF2, CF3, all three conforming to the invention, with three correction capacitors Cc1, Cc2.", "Cc3.", "The rejection frequencies may be completely different.", "The quality coefficients of the capacitors Cc1 , .", ", must be identical in value to the value of the quality coefficients of the associated inductances.", "Although this initial version of the invention may be made with discrete components, it is more convenient, when the working frequency range reaches and exceeds a gigahertz, to achieve inductance of the filter in the form of a micro-ribbon conductor.", "The invention lends itself particularly well to this technology.", "Indeed, in this case, as shown in FIG. 15, a filtering cell according to the invention can include two micro-ribbons 10 and 12 deposited on an insulating substrate 14.", "These two micro-ribbons, which can be any geometric shape, consist of two semi-inductances and also include a micro-ribbon 16.", "This micro-ribbon 16 forms, with a mass plan 18 deposited on the other side of the substrate, the correction capacitor.", "A discrete capacitor 19 completes the unit.", "One can therefore see that in this technology, the correction capacitor 16 is integrated quite naturally between the two semi-inductances 10, 12.", "One need only regulate the width of the micro-ribbon 16 to obtain the appropriate capacitance Cc.", "Several cells of this type can be placed end to end on the same substrate.", "One may also fold the substrate as shown in FIG. 16.", "A substrate 20 consists of two insulating plates 21 and 22 separated by a conductive plane 23.", "On the front of the plate 21, there are two filtering cells similar to the one in FIG. 15, or CF1 and CF2.", "A metallized hole 25 (insulated from the plane 23) makes it possible to establish an electrical connection with the back of the plate 22, which has two cells like CF1 and CF2 (not visible in the Figure).", "The input and output of the filter is handled by the connectors 30 and 32, respectively.", "The different methods of execution which have just been described correspond to a case where correction is carried out on the inductance of the resonant circuit by an ad hoc quality coefficient capacitor.", "But the invention covers a case where correction is carried out on the capacitor of the resonant circuit with an inductance associated with a resistor.", "The corresponding cell is illustrated in FIG. 17.", "The capacitor is split into two capacitors with a value of 2c connected in series with a midpoint M. Between this point and the mass, an inductance with a value Lc and a correction resistor Rc in series are connected.", "Moreover, the main inductance L is associated with a resistor R1, and R1 is connected to the quality factor L. The other media are identical to those in FIG. 4 FIGS. 18A, B, C illustrate the performance obtained.", "The results shown should be compared with the results illustrated in FIGS. 3B, 3D and 3F, respectively, compared to a cell of the prior state of the art.", "One can see, particularly in FIG. 18A, an attenuation of -32 dB at the rejection frequency (compared with -28 dB);", "in FIG. 18B losses from 0.4 dB to 800 MHz and from 1.5 dB to 600 MHz (compared to 1.2 and 2.5 dB, respectively);", "and lastly, in FIG. 18C a mismatch of -26 dB to 800 MHz (compared to -13 dB).", "The theoretical and experimental work of the inventors has shown that there is a wide choice of values for the correction elements Lc and Rc The maximum value of Lc is 1/2R 1 C 2 w o 3 and in this case the correction resistance Rc is equal to L c w o .", "Then, there must be ##EQU1## If a value of Lc is chosen that is lower than the maximum value, then Rc can have two values: ##EQU2## with K=R1C 2 w o 2 and A= 1-4K 2 Lc 2 w o 2 and it is still necessary to require ##EQU3## In these equations, L and R1 are the inductance of the resonant circuit with its associated interference resistor which determines the quality coefficient, C is the capacitance of the capacitor of the resonant circuit, w o is the resonance pulsation chosen with w o =2πFo, where Fo is the resonance frequency." ]
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a method and a system of processing an automobile insurance, and in particular, a method and a system of processing an automobile insurance according to driving distance and time of a vehicle. [0003] 2. Description of the Prior Art [0004] The current automobile insurances are period-based insurances, which compensate for an accident occurred during the period of insurance according to an article of the corresponding insurance once after a vehicle owner pre-pays an insurance fee. [0005] U.S. Pat. No. 5,797,134 (Aug. 8, 1998) discloses a method of calculating an insurance fee by obtaining driving information on a vehicle, while U.S. Pat. No. 5,459,304 (Oct. 17, 1995) and French Application Serial No. 93/05406 (Apr. 30, 1993) disclose a technique of renewing the period of an insurance through communication with the insurance company after elapse of a predetermined period of time by using a card-type insurance card loaded on a vehicle. However, those methods teach a renewal of an insurance through communication with the insurance company upon expiry of the insurance recorded on a card irrespective of a driving distance or a driving time of a vehicle. The calculation of an insurance fee may be made by investigating databasing the information on vehicle law violation, driving distance, driving time, etc. so as to enhance efficiency of determining an insurance fee at the time of subscribing the insurance. However, those methods are nothing more than a manner of extinguishing an insurance fee after elapse of a certain period of time irrespective of a driving time, driving distance or a driving velocity of a vehicle. Therefore, those methods are disadvantageous for the motorists who do not drive the vehicles so frequently or do not violate the vehicle law. SUMMARY OF THE INVENTION [0006] It is, therefore, an object of the present invention to provide a method and a system for processing automobile insurance by using a card capable of calculating an insurance fee on a rational basis by considering a driving time, driving distance and a driving velocity of a vehicle once after a driver purchases a debit insurance card effective for a set period of time or distance. [0007] To achieve the above and other objects, there is provided a method for processing an automobile insurance according to a driving time and distance by using a card, comprising the steps of: purchasing a card, on which a predetermined amount of an insurance value is recorded through calculation of the insurance fee at a discriminated price according to the conventional method of calculating an insurance fee; and recording a remaining insurance value and information on a vehicle driving on the card based on the calculated result. [0008] To achieve the above and other objects, there is also provided a device for processing an automobile insurance according to a driving time and distance, comprising: a card recording a predetermined amount of an insurance fee; driving sensing means for sensing a driving time or distance of a vehicle; processing means for reading information on the insurance recorded on the card if the card is inserted thereto to display a remaining insurance value and calculate a predetermined amount of the extinguished insurance value, subtracting the extinguished insurance value from the remaining insurance value according to a driving time or distance inputted from the driving sensing means, and recording the remaining insurance value on the card. BRIEF DESCRIPTION OF THE DRAWINGS [0009] The above and other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which: [0010] [0010]FIG. 1 is a conceptual diagram illustrating a concept of processing an automobile insurance by using a card according to the present invention; [0011] [0011]FIG. 2 is a schematic diagram illustrating an insurance processing system mounted on a vehicle according to the present invention; [0012] [0012]FIGS. 3A and 3B are views of cards according to embodiments of the present invention; [0013] [0013]FIG. 4 is a flow chart illustrating a process of extinguishing an insurance value of a card according to a first embodiment of the present invention; [0014] [0014]FIG. 5 is a flow chart illustrating a process of calculating an extinguished insurance value discriminatingly applicable in accordance with a velocity of a vehicle according to the second embodiment of the present invention; [0015] [0015]FIG. 6 is a flow chart illustrating a process of extinguishing an insurance value according to a third embodiment of the present invention; and [0016] [0016]FIG. 7 is a flow chart illustrating a process of extinguishing an insurance value according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0017] Preferred embodiments of the present invention will be described herein below with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. [0018] [0018]FIG. 1 is a conceptual diagram illustrating a concept of processing an automobile insurance by using a card according to the present invention. According to FIG. 1, a client 104 purchases a card 106 by paying a predetermined amount of an insurance fee to an insurance company 102 . The card 106 here may be a prepaid card, credit card, or a transportation card, etc., and may be classified into a time-set type and a distance-set type according to an “insurance value” (i.e., the insuring time or distance), as shown in FIGS. 3A and 3B. [0019] There are two types of extinguishing the insurance value recorded on the card: extinguishing the value according to a driving time; and extinguishing the value according to a driving distance. Even each of these two types can further be classified into two manners: an absolute manner of extinguishing the value by considering either a driving time or a driving distance only; and a conditioned manner of extinguishing the value by considering driving conditions (a driving velocity, etc.) in addition to the driving time or the driving distance. Another available manner is a combined manner of considering both the driving time and distance. [0020] Referring to FIG. 1, an insurance processing device 108 is mounted on a vehicle 112 , to which the present invention is applicable. The client 104 purchases the card 106 from the insurance company 112 , and inserts the card 106 to the insurance processing device 108 when starting up the vehicle 112 . Once the vehicle l 12 is driven, the card 106 senses the insured time or distance depending on a driving time or distance according to the present invention. If a traffic accident occurs in the course of driving, a driver reports the accident to a police 116 and to the insurance company 102 . The insurance company then collects the card 106 to read the driving information and determine validity of the card so as to compensate for an insurance amount to the injured and the insurance subscriber (client) according to the insurance article. [0021] Thus, the insurance fee can be settled on a rational basis because the insurance value is extinguished depending on the driving time or distance and only when the vehicle 112 is on a driving status. [0022] [0022]FIG. 2 is a schematic diagram illustrating an insurance processing system mounted on a vehicle according to the present invention. FIG. 2 shows that an insurance processing system 108 comprises a microprocessor( 202 ), a driving distance sensing section 204 , a driving velocity sensing section 206 , a driving sensing section 208 , a buzzer 216 , a display section 218 , a card input/output section 220 , a memory device 221 , an input device 222 , and a communication control section 223 . [0023] Referring to FIG. 2, the debit insurance card (hereinafter, referred to as a “card”) 106 records information related to calculation of an insurance value including an insurance fee calculating formula of an insurance value rate according to a driving time or a driving distance, a type of an insurance such as an amount-set type, a time-set type or a distance-set type, and personal information of the insurance subscriber, etc. The card 106 can record or delete such information on a recording section comprising a semiconductor chip including a flash memory, etc. or a magnetic tape. [0024] If the driver 110 of a vehicle having a prepaid card-type insurance processing system inputs a start-up key to the vehicle for start-up, the microprocessor 202 of the prepaid card-type insurance processing system determines whether or not the card has been inserted to the card input/output section 220 of the card reader, which can read or record the information on the card 106 . [0025] In the negative, the microprocessor 202 either transmits characters requiring an insertion of the card 106 to the display section 218 or generates a buzzer sound through the buzzer 216 . [0026] Though not shown in the drawings, an additional function may be annexed to the prepaid-type insurance processing system so as to cease the start-up of the vehicle by transmitting a driving cessation signal to a vehicle driving control device (a start-up key control section, etc.). [0027] In the affirmative, the microprocessor 202 displays an amount of insurance value according to the drivable time and distance among the data read by the card reader. [0028] The microprocessor 202 records the information on the insurance fee rate calculation formula and the data on a type of the insurance inputted from the card 106 on the memory device 221 such as RAM, etc. housed in the microprocessor 202 . Also, in consideration of a recording capacity of the card 106 , the insurance value may be calculated by using the memory device 221 comprising a fixed semiconductor chip such as ROM, etc. in the microprocessor 202 to record the information on the insurance fee rate calculation depending on the type of insurance. [0029] If the vehicle starts driving, driving information is inputted to the microprocessor 202 from the driving distance sensing section 204 , driving velocity sensing section 206 , driving sensing section 208 , etc. [0030] A generic device may be utilized as the device of sensing the driving information to extract data required for the present invention. A tachometer, commercialized as a driving recorder, may be utilized if necessary. [0031] The microprocessor 202 computes information related to the insurance recorded in the memory device 221 of the microprocessor and the driving information to calculate a remaining insurance value or a used insurance value (hereinafter, referred to as a “remaining insurance value”). The calculated result is stored in a storing device 224 comprising a RAM, a rewritable CD, a magnetic recording tape, etc., which are controlled by the microprocessor 202 . The data stored in the storing device 224 are periodically (in a minute unit or a km unit) transmitted to the card reader by the microprocessor 202 so as to extinguish the remaining insurance value of the card for renewal of the insurance value. If a driving cessation signal is inputted from the driving information sensing section, the microprocessor 202 transmits the final data of the storing device 224 to the card reader so as to extinguish the used amount from the remaining insurance value for renewal of the remaining insurance value. [0032] In case the extinction is simply an insurance fee extinction performed according to a driving time or distance based on the agreement between the insurance company and the driver, information on time and distance, personal information, a type of the insurance, etc. are recorded on the card except the information on the insurance fee rate calculation. Thus, it is obvious to those skilled in the art that the microprocessor 202 needs not perform computation for an insurance fee calculation. What also belongs to the category of the present invention are that the microprocessor 202 receives the driving information during driving from the driving sensing devices without the storing device 224 controlled by the microprocessor 202 , and transmits the received information to the card reader in real time for renewal of the insurance value recorded on the card. [0033] The microprocessor 202 stores the data inputted from the driving information sensing devices in the storing device 224 , and may periodically delete the stored data considering the capacity of the storing device 224 , etc. The microprocessor 202 may also transmit the stored data to the card reader and record the driving information on the card so as to grasp the driving status before an accident, if occurred, and utilize the recorded information as a statistical material for calculating insurance fees. [0034] The driver accesses the insurance company via telephone or a public communication network such as data communication network through internet by utilizing a wire or wireless telecommunication network connected to the communication control section 223 , which is controlled by the microprocessor 202 when an additional subscription is determined to be required by reference to the remaining insuring distance and time as well as to the remaining insurance value. Thereafter, personal information including the ID, the password set at the time of subscribing the insurance is transmitted by the input device 222 or by means of a vocal communication so that the microprocessor 202 can receive the required insurance value including the insuring distance and time via a wire or wireless public communication network and the communication control section 223 . The microprocessor 202 transmits the received information to the card reader to renew the remaining insurance value recorded on the card. [0035] It is obvious to those skilled in the art that the driver may renew the information related to the insurance recorded on the card by means of a card charger installed at affiliated shops designated by the insurance company. [0036] [0036]FIG. 3A is an exemplary card of a time-set type according to the present invention that may be classified into a 12-hour card, a 24-hour card, a 48-hour card, a three-day card, a week card, a month card, a three-month card, etc. according to an insuring time. FIG. 3B is an exemplary card of a distance-set type card according to the present invention that may be classified into a 100 km card, a 500 km card, a 1000 km card, a 10,000 km card, a 30,000 km card, etc. according to an insuring distance. Such cards can be realized by IC cards or magnetic cards, on which the insuring time/distance, the insurance company, user's manual may be printed. Electro-magnetically, the cards may record the data such as the card number, the code of a card type, the code of the insurance company, the remaining distance/time, the extinguished time/distance, the driving information, the time of accident, etc. according to a predetermined format. [0037] [0037]FIG. 4 is a flow chart illustrating a process of extinguishing an insurance value of a card according to a first embodiment of the present invention. The client ( 104 in FIG. 1) purchases a card from the insurance company 102 at a price discriminated according to the conventional insurance fee calculating method. The client 104 then inserts the card to the debit-type insurance processing device 108 mounted on a vehicle when starting up the vehicle. [0038] If the start-up key is inserted to the vehicle for driving, a power supply is applied to the insurance processing system 108 of the present invention (S 401 ). Subsequently, the microprocessor 202 operates to initialize diverse parameter values (S 402 ). It is then determined whether or not the card 106 has been inserted (S 403 ). In the negative, a buzzer 216 is sounded or characters are displayed such that “Insert the card” on the display section 218 to require insertion of the card (S 404 ). [0039] In the affirmative, the card input/output section 220 reads the information recorded on the card (S 405 ). The information recorded on the card includes a type of the card (a time-set type or a distance-set type, etc.) and an insurance value such as the remaining insurance time/distance, etc. The read-in insurance value is displayed on the display section 218 comprising an LCD. The information on the insurance fee rate calculation recorded on the card is recorded in a RAM, which is a memory device 221 of the microprocessor 202 . In case that the insurance fee rate calculation formula is pre-set in a ROM of the microprocessor 202 , the ROM is activated. [0040] The vehicle is driven if the insurance value displayed on the display section 218 is “0” or if no necessity to add the insurance value (or to renew the insurance) is determined by the driver (S 406 ). [0041] In case that the remaining insurance value is “0”, the microprocessor 202 either sounds the buzzer 216 for warning or displays a warning phrase such as “No insurance applicable” on the display section 218 . [0042] In case that a necessity to add the insurance value is determined, the driver accesses the insurance company via a wire or wireless telecommunication network or a data communication network to perform a process of adding the insurance value (S 501 ) as will be described later. [0043] As the vehicle is driven, the vehicle driving information is inputted to the microprocessor 202 from the driving information sensing devices such as the driving distance sensing section 204 , the driving velocity sensing section 206 , etc. (S 407 ). [0044] The microprocessor 202 calculates the used insurance value based on the inputted driving information and the type of insurance inputted from the card or the insurance fee rate calculating formula already inputted to the microprocessor 202 (S 408 ). The microprocessor 202 then calculates the used insurance vale based on the remaining insurance value inputted from the card (S 409 ), and stores the used insurance value in the storing device 224 (S 410 ). The microprocessor 202 then determines whether or not the driving has been terminated by reference to the driving information inputted from the driving information sensing devices (S 411 ). If the driving is determined to have been terminated, the remaining insurance value recorded in the storing device 224 is transmitted to the card reader so as to renew the remaining insurance value recorded in the card (S 412 ) and to terminate the process. [0045] The storing section for storing the result calculated in the insurance fee calculating step may record the driving information obtained in the driving information obtaining step as well. If necessary, the microprocessor 202 may periodically read out the driving information record from the storing device 224 or the card either after termination of the driving or during the driving by recording the driving information in the card. [0046] At this stage, the insurance fee is calculated in the calculation step (S 408 ) of the used insurance value according to the construction of the system of the present invention. It is obvious that present invention includes the process of calculating the used insurance value only without calculating the difference between the insurance fee and the remaining insurance value and stored in the calculating step (S 409 ) of the remaining insurance value, as well as the process of reading out the stored used insurance value with the card reader so as to delete the read-out value from the remaining insurance value recorded in the card upon termination of the driving. [0047] It is also obvious that the present invention includes a possibility of omitting the step of storing in the storing device 224 if the system is constructed to calculate the remaining insurance value and the used insurance value in real time and to extinguish the remaining insurance value recorded on the card according to the present invention. [0048] If the driver determines a necessity to add an insurance value in step 406 of determining whether or not to add the insurance value, the driver communicates with the insurance company via a wire or wireless telecommunication network or a data communication network so as to add the insurance value or renew the insurance via the communication control section 223 controlled by the microprocessor 202 . [0049] According to the an embodiment of the present invention, the communication control section 223 controlled by the microprocessor 202 for adding the insurance value or renewing the insurance is preferably a wire or wireless modem or the one that can be combined with a wire or wireless telecommunication terminal. The microprocessor 202 accesses the server of the insurance company by using a wire or wireless terminal connected to the communication control section 223 by operating a communication software such as a web browser for internet connection, e.g., an Internet Explorer of Microsoft Corporation (S 501 ). The server of the insurance company requires personal information and a password of the driver given at the time of the subscribing the insurance. The driver inputs the above requisites by means of the input device 222 controlled by the microprocessor 202 . The server of the insurance company then identifies the driver (S 502 ). Once the driver is identified to be an insurance subscriber, the server of the insurance company receives a window for inputting the insurance value and the data related to a settlement of the insurance fee including the credit card number, the bank account number, etc. of the driver (S 503 ) to determine whether or not to approve addition of the insurance value (S 504 ). When approved, the added value of the insurance fee as requested by the driver is transmitted to the microprocessor 202 of the driver's vehicle. The microprocessor 202 receives and displays the transmitted value on the display section 218 (S 507 ), while transmitting the same to the card reader (S 508 ) to renew the remaining insurance value recorded on the card. [0050] The insurance value can be renewed by the card alone, according to the present invention, when used in a shop installing an insurance value renewing device connected to an insurance company for the purpose of renewing the insurance value such as an addition or a renewal of the insurance. [0051] An operation of the card value renewing terminal may be realized with the technology well-known in the recycling field of recharging the card when no value remains as a result of reducing the value according to the data recorded on the card. [0052] [0052]FIG. 5 is a flow chart illustrating a process of calculating an extinguished insurance value discriminatingly applicable in accordance with a velocity of a vehicle according to another embodiment (hereinafter, referred to as “a second embodiment”) of the present invention. FIG. 5 shows the same process as FIG. 4 as long as the step of obtaining the driving information, while illustrating the step of calculating the insurance fee in detail. Therefore, steps 601 , 602 , 603 , 604 , 605 , and 606 are performed to be the same as the steps 401 , 402 , 403 , 404 , 405 , and 406 in FIG. 4 illustrating a flow according to the first embodiment of the present invention. [0053] As shown in FIG. 5, the microprocessor 202 receives information on a driving velocity from the driving information device of the vehicle (S 607 ), and selects the calculation formula received from the card or pre-inputted and memorized in the memory device 221 of the microprocessor 202 (S 608 ). The selected calculation formula is a formula for calculating an insurance value by discriminatingly applying the insurance fee applicable rates according to driving velocities as shown in Table 1 below. [0054] The microprocessor 202 detects data on velocity from the data in the driving information sensing section, and calculates the driving velocity by using the selected calculation formula to calculate the remaining insurance value (step 609 ). The microprocessor 202 then determines whether or not the driving has been terminated by reference to the driving information inputted from the driving information sensing devices (S 611 ). If the driving is determined to have been terminated, the remaining insurance value recorded in the storing device 224 is transmitted to the card reader so as to renew the remaining insurance value recorded in the card (S 612 ) and to terminate the process. TABLE 1 Driving Velocity Premium Rate Up to 120 km/h 1 120-140 km/h 1.2 Higher than 140 km/h 1.4 [0055] As shown in the above Table 1, the unit extinguishing insurance value is applied to actually extinguishing the insurance value when the driving velocity is below 120 km/h, whereas the value multiplying the unit extinguishing insurance value by 1.2 is applied to actually extinguishing the insurance value when the driving velocity is 120 km/h-140 km/h. When the driving velocity is higher than 140 km/h, the value multiplying the unit extinguishing insurance value by 1.4 is applied to actually extinguishing the insurance value. Such values in Table 1 are merely examples, and further detailed classification may be made in actual extinction of the insurance value according to the driving velocities. [0056] [0056]FIG. 6 is a flow chart illustrating a process of extinguishing an insurance value according to another embodiment (hereinafter, referred to as a “third embodiment”) of the present invention. After purchasing a card, the driver inserts the card to the card reader mounted in a vehicle. The microprocessor 202 then reads in the information related to the insurance including the insurance value, etc., and memorizes the same I the memory device 221 . The memory device 221 used here is preferably an EEPROM or an element having an equal or a higher function, which can always memorize the recorded information irrespective of the switch-on or off of the power supply and can easily delete or modify the memorized record, if necessary. [0057] Thus, once the driver inputs the card only once after its purchase in the initial driving through a card reader, the debit-type insurance processing system allows driving of a vehicle subscribing an insurance without additional insertions of the card thereafter. [0058] [0058]FIG. 6 illustrates the insurance processing steps only after the insurance information on the card has been inputted through the card reader according to the third embodiment of the present invention. Once a vehicle key is inputted by the driver for driving of the vehicle (S 701 ), the insurance processing system initializes all the device (S 702 ). The microprocessor 202 then reads out the information recorded in the memory device 221 , which has received and is storing the insurance information including the insurance value recorded on the card, and displays the remaining insurance value on the display section 218 (S 703 ). [0059] The vehicle is driven if the insurance value displayed on the display section 218 is “0”, or no necessity to add the insurance value (or to renew the insurance) is determined by the driver (S 704 ). [0060] In case that the remaining insurance value is “0”, the microprocessor 202 either sounds the buzzer 216 for warning, or displays a warning phrase such as “No insurance applicable” on the display section. [0061] In case that a necessity to add the insurance value is determined, the driver accesses the insurance company via a wire or wireless telecommunication network or a data communication network to perform a process of adding the insurance value as will be described later (S 801 ). [0062] The microprocessor 202 performs a series of steps 705 , 706 , 707 , 708 and 709 including an acquisition of driving information shown in FIG. 6 to be the same as the steps 407 , 408 , 409 , 410 and 411 in FIG. 4 illustrating a flow according to the first embodiment of the present invention. The microprocessor 202 renews the remaining insurance value recorded in the memory device by transmitting the remaining insurance value or the used insurance value to the memory device upon termination of the driving (S 710 ). [0063] Also, as in case of the first embodiment, the microprocessor 202 inserts the card to the card reader if a necessity to renew (recharge) the insurance value stored in the memory device 221 (S 801 ). The microprocessor 202 then reads out the insurance information recorded on the card to determine whether or not the read-out insurance information accords with the initially inputted insurance information (S 802 ). The microprocessor 202 subsequently displays the insurance value of the card on the display section. If any remaining insurance value exists, the microprocessor 202 transmits the remaining insurance value to the memory device to renew the insurance value of the memory device (S 803 ). If no remaining insurance value exists, the driver performs a step of receiving an insurance value on the card by accessing the insurance company. FIG. 6 illustrates these steps to be steps 804 to 811 , which are identical to the steps 501 to 508 in FIG. 4 illustrating the first embodiment of the present invention. Thus, the detailed description on the steps 804 to 811 will be omitted here. Upon renewal of the insurance value of the card (S 811 ), the microprocessor 202 reads out the insurance value of the card to renew the insurance value in the memory device (S 812 ). [0064] As in case of the first embodiment, the third embodiment of the present invention is capable of storing the driving information in the storing device 224 together with the remaining insurance value. Further, the insurance value calculation result can be transmitted to the memory device 221 in real time to renew the insurance value in the memory device. [0065] [0065]FIG. 7 is a flow chart illustrating a process of directly inputting the insurance fee agreed between the driver and the insurance company in the memory device of the prepaid-type insurance processing system mounted on a vehicle via a communication network without relying on the card according to another embodiment (hereinafter, referred to as a “fourth embodiment”) of the present invention. The prepaid-type insurance processing system according to the fourth embodiment is first installed in a vehicle upon agreement between the driver and the insurance company. Diver information related to the insurance as well as the insurance value are inputted in the memory device 221 of the system. When the insurance value has been extinguished, the driver accesses the server of the insurance company The server of the insurance company then identifies the subscriber by reference to the password registered at the time of subscription. The driver subsequently becomes able to recharge the insurance value from the insurance company via a wire or wireless telecommunication network. [0066] The microprocessor 202 receiving the insurance value through the wire or wireless telecommunication network stores the insurance value in the memory device 221 . The memory device 221 used here is preferably an EEPROM or an element having an equal or a higher function, which can always memorize the recorded information irrespective of the switch-on or off of the power supply and can easily delete or modify the memorized record, if necessary. [0067] A password is required for mutual authentication in transmitting and receiving the insurance value between the insurance company and the driver. The encoding method used here is preferably a public key method, which is a well-known technology in the encoding field. If necessary, a private key method may be selected or an encoding program developed by the insurance company may be utilized. [0068] The driver thus can receive the insurance value when installing the system of the present invention, and remotely recharge the insurance value while in use via a wire or wireless telecommunication network, if necessary. Therefore, it is possible to drive the vehicle insured to pay an insurance fee according to use of the vehicle. [0069] The following is a detailed description of the processing steps according to the fourth embodiment of the present invention. Referring to FIG. 7, the driver and the insurance company concludes an agreement on insuring conditions. The insurance company installs the prepaid-type insurance processing system in the driver's vehicle, to which the present invention is applicable. The insurance company then inputs information related to the insurance including the insurance value in the memory device 221 . [0070] The subsequent steps are identical to steps 701 through 710 as shown in FIG. 6 illustrating the third embodiment of the present invention. [0071] To be specific, once the driver inserts a key for start-up of a vehicle, the insurance processing system initializes all the devices (step 902 ). Microprocessor 202 reads out the information recorded in the memory device 221 , and displays the remaining insurance value on the display section 218 (step 903 ). [0072] The vehicle is driven, if the insurance value displayed on the display section 218 is “0”, or if no necessity to add (or renew) the insurance fee is determined by the driver (step 904 ). [0073] In case that the remaining insurance value is “0”, the microprocessor 202 either sounds the buzzer 216 for warning or displays a warning phrase such as “no insurance applicable” on the display section. [0074] In case that a necessity to add the insurance value is determined, the driver performs a process of adding the insurance value by accessing the insurance company via wire or wireless telecommunication network or a data communication network, as will be described later (step 950 ). [0075] The microprocessor 202 subsequently performs steps 905 through 909 in FIG. 7 to be identical to steps 407 through 411 in FIG. 4. Upon termination of the driving, the remaining insurance value or the used insurance value is transmitted to the memory device 221 (step 910 ) to renew the remaining insurance value recorded in the memory device. [0076] If a necessity to renew (recharge) the insurance value stored in the memory device 221 is determined as in case of the first embodiment, the driver performs a process of receiving the insurance value by accessing the insurance company as illustrated in steps 950 through 956 in FIG. 7, the description of which is omitted here due to identity to steps 501 through 506 in FIG. 4. The microprocessor 202 receives the insurance value received by the communication control section, and renew the insurance value in the memory device 221 (step 956 ). [0077] According to the fourth embodiment of the present invention, the driving information can be stored in the storing device 224 together with the remaining insurance value, as in case of the first embodiment. Also, the insurance value may be renewed by transmitting the calculated insurance value to the memory device 221 in real time. [0078] The following is a description of another embodiment (hereinafter, referred to as a “fifth embodiment”; no flow chart is shown in the drawings) of the present invention. According to the fifth embodiment, the driving information is inputted from a driving information sensor attached to a vehicle to calculate the remaining insurance value in the first through the fourth embodiments of the present invention, and is recorded in the card 106 , a storing device 224 or in the memory device 221 . The stored driving information and the remaining insurance value are periodically (e.g., once every month) read out by the microprocessor 202 and transmitted to the server of the insurance company via a wire or wireless telecommunication terminal. Otherwise, the driver may transmit the stored driving information and the remaining insurance value to the server of the insurance company through an access thereto on an irregular basis. Also, when the remaining insurance value has a predetermined value (e.g., below 10% of the subscribed insurance value), the microprocessor 202 recognizes the value, and transmits the driving information and the remaining insurance value to the server of the insurance company The server of the insurance company transmits a phrase, etc. requiring a renewal of the insurance value on the display section 218 of the insurance processing device of the present invention. [0079] When the server of the insurance company requires the recorded information through communication between the microprocessor 202 and the server of the insurance company, the microprocessor 202 reads out and transmits the pertinent information to the server of the insurance company. [0080] The server of the insurance company may make the information as a database related to an insurance subscription. The server of the insurance company transmits the remaining insurance value and record of use, etc. to the driver based on the information via E-mail, an internet terminal, or the display section 218 of the insurance processing device of the present invention. [0081] As described above, the present invention realizes a rational automobile insurance system by paying an insurance fee according to an actual driving time or distance rather than according to a period of insurance. Since the insurance fee is paid depending on the driving of a vehicle, the practice of unnecessary driving can be particularly avoided by utilizing present invention, thereby contributing to the energy policy and the transportation policy as well as to an environment in reducing the pollution. Further, driving with excessive speed can be prevented and traffic accidents can be reduced by discriminatingly imposing the insurance fee according to driving velocities. Moreover, purchasing and recharging the card for paying the insurance fee also serve for saving the expenses and user convenience. [0082] While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Disclosed are a method and a device for processing an automobile insurance, and more particularly a method and a device for processing an automobile insurance according to a driving distance and time. The method according to the invention includes the steps of purchasing a card, on which a predetermined information on the insurance is recorded, at a price discriminated according to the existing method of calculating an insurance fee, inputting the predetermined information on the insurance recorded on the purchased card to a card reader of the insurance processing system mounted on a vehicle, memorizing the information on the insurance read out by a microcomputer from the card reader in a memory device controlled by the microcomputer, and displaying the same on a display section, inputting driving information sensed by a vehicle driving information sensor connected to the prepaid card-type insurance processing system as the vehicle drives, computing a remaining insurance value or a used insurance value by means of the microcomputer based on the insurance information read out by the card and the driving information inputted by the vehicle driving information sensor, and renewing or extinguishing an insurance value recorded on the card by transmitting the remaining insurance value or the used insurance value computed by the microcomputer to the card reader. The device according to the invention includes a card, on which a predetermined insurance value is recorded, driving sensing means for sensing a driving time or distance of a vehicle, and processing means for reading out insurance information recorded on the card after the card is inserted, displaying a remaining insurance value, calculating a predetermined extinguishing insurance value, subtracting the extinguished insurance value from the remaining insurance value according to a driving time or distance inputted from the driving sensing means, and re-recording the remaining insurance value on the card.
Concisely explain the essential features and purpose of the invention.
[ "BACKGROUND OF THE INVENTION [0001] 1.", "Field of the Invention [0002] The present invention relates to a method and a system of processing an automobile insurance, and in particular, a method and a system of processing an automobile insurance according to driving distance and time of a vehicle.", "[0003] 2.", "Description of the Prior Art [0004] The current automobile insurances are period-based insurances, which compensate for an accident occurred during the period of insurance according to an article of the corresponding insurance once after a vehicle owner pre-pays an insurance fee.", "[0005] U.S. Pat. No. 5,797,134 (Aug. 8, 1998) discloses a method of calculating an insurance fee by obtaining driving information on a vehicle, while U.S. Pat. No. 5,459,304 (Oct. 17, 1995) and French Application Serial No. 93/05406 (Apr. 30, 1993) disclose a technique of renewing the period of an insurance through communication with the insurance company after elapse of a predetermined period of time by using a card-type insurance card loaded on a vehicle.", "However, those methods teach a renewal of an insurance through communication with the insurance company upon expiry of the insurance recorded on a card irrespective of a driving distance or a driving time of a vehicle.", "The calculation of an insurance fee may be made by investigating databasing the information on vehicle law violation, driving distance, driving time, etc.", "so as to enhance efficiency of determining an insurance fee at the time of subscribing the insurance.", "However, those methods are nothing more than a manner of extinguishing an insurance fee after elapse of a certain period of time irrespective of a driving time, driving distance or a driving velocity of a vehicle.", "Therefore, those methods are disadvantageous for the motorists who do not drive the vehicles so frequently or do not violate the vehicle law.", "SUMMARY OF THE INVENTION [0006] It is, therefore, an object of the present invention to provide a method and a system for processing automobile insurance by using a card capable of calculating an insurance fee on a rational basis by considering a driving time, driving distance and a driving velocity of a vehicle once after a driver purchases a debit insurance card effective for a set period of time or distance.", "[0007] To achieve the above and other objects, there is provided a method for processing an automobile insurance according to a driving time and distance by using a card, comprising the steps of: purchasing a card, on which a predetermined amount of an insurance value is recorded through calculation of the insurance fee at a discriminated price according to the conventional method of calculating an insurance fee;", "and recording a remaining insurance value and information on a vehicle driving on the card based on the calculated result.", "[0008] To achieve the above and other objects, there is also provided a device for processing an automobile insurance according to a driving time and distance, comprising: a card recording a predetermined amount of an insurance fee;", "driving sensing means for sensing a driving time or distance of a vehicle;", "processing means for reading information on the insurance recorded on the card if the card is inserted thereto to display a remaining insurance value and calculate a predetermined amount of the extinguished insurance value, subtracting the extinguished insurance value from the remaining insurance value according to a driving time or distance inputted from the driving sensing means, and recording the remaining insurance value on the card.", "BRIEF DESCRIPTION OF THE DRAWINGS [0009] The above and other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which: [0010] [0010 ]FIG. 1 is a conceptual diagram illustrating a concept of processing an automobile insurance by using a card according to the present invention;", "[0011] [0011 ]FIG. 2 is a schematic diagram illustrating an insurance processing system mounted on a vehicle according to the present invention;", "[0012] [0012 ]FIGS. 3A and 3B are views of cards according to embodiments of the present invention;", "[0013] [0013 ]FIG. 4 is a flow chart illustrating a process of extinguishing an insurance value of a card according to a first embodiment of the present invention;", "[0014] [0014 ]FIG. 5 is a flow chart illustrating a process of calculating an extinguished insurance value discriminatingly applicable in accordance with a velocity of a vehicle according to the second embodiment of the present invention;", "[0015] [0015 ]FIG. 6 is a flow chart illustrating a process of extinguishing an insurance value according to a third embodiment of the present invention;", "and [0016] [0016 ]FIG. 7 is a flow chart illustrating a process of extinguishing an insurance value according to a fourth embodiment of the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0017] Preferred embodiments of the present invention will be described herein below with reference to the accompanying drawings.", "In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.", "[0018] [0018 ]FIG. 1 is a conceptual diagram illustrating a concept of processing an automobile insurance by using a card according to the present invention.", "According to FIG. 1, a client 104 purchases a card 106 by paying a predetermined amount of an insurance fee to an insurance company 102 .", "The card 106 here may be a prepaid card, credit card, or a transportation card, etc.", ", and may be classified into a time-set type and a distance-set type according to an “insurance value”", "(i.e., the insuring time or distance), as shown in FIGS. 3A and 3B.", "[0019] There are two types of extinguishing the insurance value recorded on the card: extinguishing the value according to a driving time;", "and extinguishing the value according to a driving distance.", "Even each of these two types can further be classified into two manners: an absolute manner of extinguishing the value by considering either a driving time or a driving distance only;", "and a conditioned manner of extinguishing the value by considering driving conditions (a driving velocity, etc.) in addition to the driving time or the driving distance.", "Another available manner is a combined manner of considering both the driving time and distance.", "[0020] Referring to FIG. 1, an insurance processing device 108 is mounted on a vehicle 112 , to which the present invention is applicable.", "The client 104 purchases the card 106 from the insurance company 112 , and inserts the card 106 to the insurance processing device 108 when starting up the vehicle 112 .", "Once the vehicle l 12 is driven, the card 106 senses the insured time or distance depending on a driving time or distance according to the present invention.", "If a traffic accident occurs in the course of driving, a driver reports the accident to a police 116 and to the insurance company 102 .", "The insurance company then collects the card 106 to read the driving information and determine validity of the card so as to compensate for an insurance amount to the injured and the insurance subscriber (client) according to the insurance article.", "[0021] Thus, the insurance fee can be settled on a rational basis because the insurance value is extinguished depending on the driving time or distance and only when the vehicle 112 is on a driving status.", "[0022] [0022 ]FIG. 2 is a schematic diagram illustrating an insurance processing system mounted on a vehicle according to the present invention.", "FIG. 2 shows that an insurance processing system 108 comprises a microprocessor( 202 ), a driving distance sensing section 204 , a driving velocity sensing section 206 , a driving sensing section 208 , a buzzer 216 , a display section 218 , a card input/output section 220 , a memory device 221 , an input device 222 , and a communication control section 223 .", "[0023] Referring to FIG. 2, the debit insurance card (hereinafter, referred to as a “card”) 106 records information related to calculation of an insurance value including an insurance fee calculating formula of an insurance value rate according to a driving time or a driving distance, a type of an insurance such as an amount-set type, a time-set type or a distance-set type, and personal information of the insurance subscriber, etc.", "The card 106 can record or delete such information on a recording section comprising a semiconductor chip including a flash memory, etc.", "or a magnetic tape.", "[0024] If the driver 110 of a vehicle having a prepaid card-type insurance processing system inputs a start-up key to the vehicle for start-up, the microprocessor 202 of the prepaid card-type insurance processing system determines whether or not the card has been inserted to the card input/output section 220 of the card reader, which can read or record the information on the card 106 .", "[0025] In the negative, the microprocessor 202 either transmits characters requiring an insertion of the card 106 to the display section 218 or generates a buzzer sound through the buzzer 216 .", "[0026] Though not shown in the drawings, an additional function may be annexed to the prepaid-type insurance processing system so as to cease the start-up of the vehicle by transmitting a driving cessation signal to a vehicle driving control device (a start-up key control section, etc.).", "[0027] In the affirmative, the microprocessor 202 displays an amount of insurance value according to the drivable time and distance among the data read by the card reader.", "[0028] The microprocessor 202 records the information on the insurance fee rate calculation formula and the data on a type of the insurance inputted from the card 106 on the memory device 221 such as RAM, etc.", "housed in the microprocessor 202 .", "Also, in consideration of a recording capacity of the card 106 , the insurance value may be calculated by using the memory device 221 comprising a fixed semiconductor chip such as ROM, etc.", "in the microprocessor 202 to record the information on the insurance fee rate calculation depending on the type of insurance.", "[0029] If the vehicle starts driving, driving information is inputted to the microprocessor 202 from the driving distance sensing section 204 , driving velocity sensing section 206 , driving sensing section 208 , etc.", "[0030] A generic device may be utilized as the device of sensing the driving information to extract data required for the present invention.", "A tachometer, commercialized as a driving recorder, may be utilized if necessary.", "[0031] The microprocessor 202 computes information related to the insurance recorded in the memory device 221 of the microprocessor and the driving information to calculate a remaining insurance value or a used insurance value (hereinafter, referred to as a “remaining insurance value”).", "The calculated result is stored in a storing device 224 comprising a RAM, a rewritable CD, a magnetic recording tape, etc.", ", which are controlled by the microprocessor 202 .", "The data stored in the storing device 224 are periodically (in a minute unit or a km unit) transmitted to the card reader by the microprocessor 202 so as to extinguish the remaining insurance value of the card for renewal of the insurance value.", "If a driving cessation signal is inputted from the driving information sensing section, the microprocessor 202 transmits the final data of the storing device 224 to the card reader so as to extinguish the used amount from the remaining insurance value for renewal of the remaining insurance value.", "[0032] In case the extinction is simply an insurance fee extinction performed according to a driving time or distance based on the agreement between the insurance company and the driver, information on time and distance, personal information, a type of the insurance, etc.", "are recorded on the card except the information on the insurance fee rate calculation.", "Thus, it is obvious to those skilled in the art that the microprocessor 202 needs not perform computation for an insurance fee calculation.", "What also belongs to the category of the present invention are that the microprocessor 202 receives the driving information during driving from the driving sensing devices without the storing device 224 controlled by the microprocessor 202 , and transmits the received information to the card reader in real time for renewal of the insurance value recorded on the card.", "[0033] The microprocessor 202 stores the data inputted from the driving information sensing devices in the storing device 224 , and may periodically delete the stored data considering the capacity of the storing device 224 , etc.", "The microprocessor 202 may also transmit the stored data to the card reader and record the driving information on the card so as to grasp the driving status before an accident, if occurred, and utilize the recorded information as a statistical material for calculating insurance fees.", "[0034] The driver accesses the insurance company via telephone or a public communication network such as data communication network through internet by utilizing a wire or wireless telecommunication network connected to the communication control section 223 , which is controlled by the microprocessor 202 when an additional subscription is determined to be required by reference to the remaining insuring distance and time as well as to the remaining insurance value.", "Thereafter, personal information including the ID, the password set at the time of subscribing the insurance is transmitted by the input device 222 or by means of a vocal communication so that the microprocessor 202 can receive the required insurance value including the insuring distance and time via a wire or wireless public communication network and the communication control section 223 .", "The microprocessor 202 transmits the received information to the card reader to renew the remaining insurance value recorded on the card.", "[0035] It is obvious to those skilled in the art that the driver may renew the information related to the insurance recorded on the card by means of a card charger installed at affiliated shops designated by the insurance company.", "[0036] [0036 ]FIG. 3A is an exemplary card of a time-set type according to the present invention that may be classified into a 12-hour card, a 24-hour card, a 48-hour card, a three-day card, a week card, a month card, a three-month card, etc.", "according to an insuring time.", "FIG. 3B is an exemplary card of a distance-set type card according to the present invention that may be classified into a 100 km card, a 500 km card, a 1000 km card, a 10,000 km card, a 30,000 km card, etc.", "according to an insuring distance.", "Such cards can be realized by IC cards or magnetic cards, on which the insuring time/distance, the insurance company, user's manual may be printed.", "Electro-magnetically, the cards may record the data such as the card number, the code of a card type, the code of the insurance company, the remaining distance/time, the extinguished time/distance, the driving information, the time of accident, etc.", "according to a predetermined format.", "[0037] [0037 ]FIG. 4 is a flow chart illustrating a process of extinguishing an insurance value of a card according to a first embodiment of the present invention.", "The client ( 104 in FIG. 1) purchases a card from the insurance company 102 at a price discriminated according to the conventional insurance fee calculating method.", "The client 104 then inserts the card to the debit-type insurance processing device 108 mounted on a vehicle when starting up the vehicle.", "[0038] If the start-up key is inserted to the vehicle for driving, a power supply is applied to the insurance processing system 108 of the present invention (S 401 ).", "Subsequently, the microprocessor 202 operates to initialize diverse parameter values (S 402 ).", "It is then determined whether or not the card 106 has been inserted (S 403 ).", "In the negative, a buzzer 216 is sounded or characters are displayed such that “Insert the card”", "on the display section 218 to require insertion of the card (S 404 ).", "[0039] In the affirmative, the card input/output section 220 reads the information recorded on the card (S 405 ).", "The information recorded on the card includes a type of the card (a time-set type or a distance-set type, etc.) and an insurance value such as the remaining insurance time/distance, etc.", "The read-in insurance value is displayed on the display section 218 comprising an LCD.", "The information on the insurance fee rate calculation recorded on the card is recorded in a RAM, which is a memory device 221 of the microprocessor 202 .", "In case that the insurance fee rate calculation formula is pre-set in a ROM of the microprocessor 202 , the ROM is activated.", "[0040] The vehicle is driven if the insurance value displayed on the display section 218 is “0”", "or if no necessity to add the insurance value (or to renew the insurance) is determined by the driver (S 406 ).", "[0041] In case that the remaining insurance value is “0”, the microprocessor 202 either sounds the buzzer 216 for warning or displays a warning phrase such as “No insurance applicable”", "on the display section 218 .", "[0042] In case that a necessity to add the insurance value is determined, the driver accesses the insurance company via a wire or wireless telecommunication network or a data communication network to perform a process of adding the insurance value (S 501 ) as will be described later.", "[0043] As the vehicle is driven, the vehicle driving information is inputted to the microprocessor 202 from the driving information sensing devices such as the driving distance sensing section 204 , the driving velocity sensing section 206 , etc.", "(S 407 ).", "[0044] The microprocessor 202 calculates the used insurance value based on the inputted driving information and the type of insurance inputted from the card or the insurance fee rate calculating formula already inputted to the microprocessor 202 (S 408 ).", "The microprocessor 202 then calculates the used insurance vale based on the remaining insurance value inputted from the card (S 409 ), and stores the used insurance value in the storing device 224 (S 410 ).", "The microprocessor 202 then determines whether or not the driving has been terminated by reference to the driving information inputted from the driving information sensing devices (S 411 ).", "If the driving is determined to have been terminated, the remaining insurance value recorded in the storing device 224 is transmitted to the card reader so as to renew the remaining insurance value recorded in the card (S 412 ) and to terminate the process.", "[0045] The storing section for storing the result calculated in the insurance fee calculating step may record the driving information obtained in the driving information obtaining step as well.", "If necessary, the microprocessor 202 may periodically read out the driving information record from the storing device 224 or the card either after termination of the driving or during the driving by recording the driving information in the card.", "[0046] At this stage, the insurance fee is calculated in the calculation step (S 408 ) of the used insurance value according to the construction of the system of the present invention.", "It is obvious that present invention includes the process of calculating the used insurance value only without calculating the difference between the insurance fee and the remaining insurance value and stored in the calculating step (S 409 ) of the remaining insurance value, as well as the process of reading out the stored used insurance value with the card reader so as to delete the read-out value from the remaining insurance value recorded in the card upon termination of the driving.", "[0047] It is also obvious that the present invention includes a possibility of omitting the step of storing in the storing device 224 if the system is constructed to calculate the remaining insurance value and the used insurance value in real time and to extinguish the remaining insurance value recorded on the card according to the present invention.", "[0048] If the driver determines a necessity to add an insurance value in step 406 of determining whether or not to add the insurance value, the driver communicates with the insurance company via a wire or wireless telecommunication network or a data communication network so as to add the insurance value or renew the insurance via the communication control section 223 controlled by the microprocessor 202 .", "[0049] According to the an embodiment of the present invention, the communication control section 223 controlled by the microprocessor 202 for adding the insurance value or renewing the insurance is preferably a wire or wireless modem or the one that can be combined with a wire or wireless telecommunication terminal.", "The microprocessor 202 accesses the server of the insurance company by using a wire or wireless terminal connected to the communication control section 223 by operating a communication software such as a web browser for internet connection, e.g., an Internet Explorer of Microsoft Corporation (S 501 ).", "The server of the insurance company requires personal information and a password of the driver given at the time of the subscribing the insurance.", "The driver inputs the above requisites by means of the input device 222 controlled by the microprocessor 202 .", "The server of the insurance company then identifies the driver (S 502 ).", "Once the driver is identified to be an insurance subscriber, the server of the insurance company receives a window for inputting the insurance value and the data related to a settlement of the insurance fee including the credit card number, the bank account number, etc.", "of the driver (S 503 ) to determine whether or not to approve addition of the insurance value (S 504 ).", "When approved, the added value of the insurance fee as requested by the driver is transmitted to the microprocessor 202 of the driver's vehicle.", "The microprocessor 202 receives and displays the transmitted value on the display section 218 (S 507 ), while transmitting the same to the card reader (S 508 ) to renew the remaining insurance value recorded on the card.", "[0050] The insurance value can be renewed by the card alone, according to the present invention, when used in a shop installing an insurance value renewing device connected to an insurance company for the purpose of renewing the insurance value such as an addition or a renewal of the insurance.", "[0051] An operation of the card value renewing terminal may be realized with the technology well-known in the recycling field of recharging the card when no value remains as a result of reducing the value according to the data recorded on the card.", "[0052] [0052 ]FIG. 5 is a flow chart illustrating a process of calculating an extinguished insurance value discriminatingly applicable in accordance with a velocity of a vehicle according to another embodiment (hereinafter, referred to as “a second embodiment”) of the present invention.", "FIG. 5 shows the same process as FIG. 4 as long as the step of obtaining the driving information, while illustrating the step of calculating the insurance fee in detail.", "Therefore, steps 601 , 602 , 603 , 604 , 605 , and 606 are performed to be the same as the steps 401 , 402 , 403 , 404 , 405 , and 406 in FIG. 4 illustrating a flow according to the first embodiment of the present invention.", "[0053] As shown in FIG. 5, the microprocessor 202 receives information on a driving velocity from the driving information device of the vehicle (S 607 ), and selects the calculation formula received from the card or pre-inputted and memorized in the memory device 221 of the microprocessor 202 (S 608 ).", "The selected calculation formula is a formula for calculating an insurance value by discriminatingly applying the insurance fee applicable rates according to driving velocities as shown in Table 1 below.", "[0054] The microprocessor 202 detects data on velocity from the data in the driving information sensing section, and calculates the driving velocity by using the selected calculation formula to calculate the remaining insurance value (step 609 ).", "The microprocessor 202 then determines whether or not the driving has been terminated by reference to the driving information inputted from the driving information sensing devices (S 611 ).", "If the driving is determined to have been terminated, the remaining insurance value recorded in the storing device 224 is transmitted to the card reader so as to renew the remaining insurance value recorded in the card (S 612 ) and to terminate the process.", "TABLE 1 Driving Velocity Premium Rate Up to 120 km/h 1 120-140 km/h 1.2 Higher than 140 km/h 1.4 [0055] As shown in the above Table 1, the unit extinguishing insurance value is applied to actually extinguishing the insurance value when the driving velocity is below 120 km/h, whereas the value multiplying the unit extinguishing insurance value by 1.2 is applied to actually extinguishing the insurance value when the driving velocity is 120 km/h-140 km/h.", "When the driving velocity is higher than 140 km/h, the value multiplying the unit extinguishing insurance value by 1.4 is applied to actually extinguishing the insurance value.", "Such values in Table 1 are merely examples, and further detailed classification may be made in actual extinction of the insurance value according to the driving velocities.", "[0056] [0056 ]FIG. 6 is a flow chart illustrating a process of extinguishing an insurance value according to another embodiment (hereinafter, referred to as a “third embodiment”) of the present invention.", "After purchasing a card, the driver inserts the card to the card reader mounted in a vehicle.", "The microprocessor 202 then reads in the information related to the insurance including the insurance value, etc.", ", and memorizes the same I the memory device 221 .", "The memory device 221 used here is preferably an EEPROM or an element having an equal or a higher function, which can always memorize the recorded information irrespective of the switch-on or off of the power supply and can easily delete or modify the memorized record, if necessary.", "[0057] Thus, once the driver inputs the card only once after its purchase in the initial driving through a card reader, the debit-type insurance processing system allows driving of a vehicle subscribing an insurance without additional insertions of the card thereafter.", "[0058] [0058 ]FIG. 6 illustrates the insurance processing steps only after the insurance information on the card has been inputted through the card reader according to the third embodiment of the present invention.", "Once a vehicle key is inputted by the driver for driving of the vehicle (S 701 ), the insurance processing system initializes all the device (S 702 ).", "The microprocessor 202 then reads out the information recorded in the memory device 221 , which has received and is storing the insurance information including the insurance value recorded on the card, and displays the remaining insurance value on the display section 218 (S 703 ).", "[0059] The vehicle is driven if the insurance value displayed on the display section 218 is “0”, or no necessity to add the insurance value (or to renew the insurance) is determined by the driver (S 704 ).", "[0060] In case that the remaining insurance value is “0”, the microprocessor 202 either sounds the buzzer 216 for warning, or displays a warning phrase such as “No insurance applicable”", "on the display section.", "[0061] In case that a necessity to add the insurance value is determined, the driver accesses the insurance company via a wire or wireless telecommunication network or a data communication network to perform a process of adding the insurance value as will be described later (S 801 ).", "[0062] The microprocessor 202 performs a series of steps 705 , 706 , 707 , 708 and 709 including an acquisition of driving information shown in FIG. 6 to be the same as the steps 407 , 408 , 409 , 410 and 411 in FIG. 4 illustrating a flow according to the first embodiment of the present invention.", "The microprocessor 202 renews the remaining insurance value recorded in the memory device by transmitting the remaining insurance value or the used insurance value to the memory device upon termination of the driving (S 710 ).", "[0063] Also, as in case of the first embodiment, the microprocessor 202 inserts the card to the card reader if a necessity to renew (recharge) the insurance value stored in the memory device 221 (S 801 ).", "The microprocessor 202 then reads out the insurance information recorded on the card to determine whether or not the read-out insurance information accords with the initially inputted insurance information (S 802 ).", "The microprocessor 202 subsequently displays the insurance value of the card on the display section.", "If any remaining insurance value exists, the microprocessor 202 transmits the remaining insurance value to the memory device to renew the insurance value of the memory device (S 803 ).", "If no remaining insurance value exists, the driver performs a step of receiving an insurance value on the card by accessing the insurance company.", "FIG. 6 illustrates these steps to be steps 804 to 811 , which are identical to the steps 501 to 508 in FIG. 4 illustrating the first embodiment of the present invention.", "Thus, the detailed description on the steps 804 to 811 will be omitted here.", "Upon renewal of the insurance value of the card (S 811 ), the microprocessor 202 reads out the insurance value of the card to renew the insurance value in the memory device (S 812 ).", "[0064] As in case of the first embodiment, the third embodiment of the present invention is capable of storing the driving information in the storing device 224 together with the remaining insurance value.", "Further, the insurance value calculation result can be transmitted to the memory device 221 in real time to renew the insurance value in the memory device.", "[0065] [0065 ]FIG. 7 is a flow chart illustrating a process of directly inputting the insurance fee agreed between the driver and the insurance company in the memory device of the prepaid-type insurance processing system mounted on a vehicle via a communication network without relying on the card according to another embodiment (hereinafter, referred to as a “fourth embodiment”) of the present invention.", "The prepaid-type insurance processing system according to the fourth embodiment is first installed in a vehicle upon agreement between the driver and the insurance company.", "Diver information related to the insurance as well as the insurance value are inputted in the memory device 221 of the system.", "When the insurance value has been extinguished, the driver accesses the server of the insurance company The server of the insurance company then identifies the subscriber by reference to the password registered at the time of subscription.", "The driver subsequently becomes able to recharge the insurance value from the insurance company via a wire or wireless telecommunication network.", "[0066] The microprocessor 202 receiving the insurance value through the wire or wireless telecommunication network stores the insurance value in the memory device 221 .", "The memory device 221 used here is preferably an EEPROM or an element having an equal or a higher function, which can always memorize the recorded information irrespective of the switch-on or off of the power supply and can easily delete or modify the memorized record, if necessary.", "[0067] A password is required for mutual authentication in transmitting and receiving the insurance value between the insurance company and the driver.", "The encoding method used here is preferably a public key method, which is a well-known technology in the encoding field.", "If necessary, a private key method may be selected or an encoding program developed by the insurance company may be utilized.", "[0068] The driver thus can receive the insurance value when installing the system of the present invention, and remotely recharge the insurance value while in use via a wire or wireless telecommunication network, if necessary.", "Therefore, it is possible to drive the vehicle insured to pay an insurance fee according to use of the vehicle.", "[0069] The following is a detailed description of the processing steps according to the fourth embodiment of the present invention.", "Referring to FIG. 7, the driver and the insurance company concludes an agreement on insuring conditions.", "The insurance company installs the prepaid-type insurance processing system in the driver's vehicle, to which the present invention is applicable.", "The insurance company then inputs information related to the insurance including the insurance value in the memory device 221 .", "[0070] The subsequent steps are identical to steps 701 through 710 as shown in FIG. 6 illustrating the third embodiment of the present invention.", "[0071] To be specific, once the driver inserts a key for start-up of a vehicle, the insurance processing system initializes all the devices (step 902 ).", "Microprocessor 202 reads out the information recorded in the memory device 221 , and displays the remaining insurance value on the display section 218 (step 903 ).", "[0072] The vehicle is driven, if the insurance value displayed on the display section 218 is “0”, or if no necessity to add (or renew) the insurance fee is determined by the driver (step 904 ).", "[0073] In case that the remaining insurance value is “0”, the microprocessor 202 either sounds the buzzer 216 for warning or displays a warning phrase such as “no insurance applicable”", "on the display section.", "[0074] In case that a necessity to add the insurance value is determined, the driver performs a process of adding the insurance value by accessing the insurance company via wire or wireless telecommunication network or a data communication network, as will be described later (step 950 ).", "[0075] The microprocessor 202 subsequently performs steps 905 through 909 in FIG. 7 to be identical to steps 407 through 411 in FIG. 4. Upon termination of the driving, the remaining insurance value or the used insurance value is transmitted to the memory device 221 (step 910 ) to renew the remaining insurance value recorded in the memory device.", "[0076] If a necessity to renew (recharge) the insurance value stored in the memory device 221 is determined as in case of the first embodiment, the driver performs a process of receiving the insurance value by accessing the insurance company as illustrated in steps 950 through 956 in FIG. 7, the description of which is omitted here due to identity to steps 501 through 506 in FIG. 4. The microprocessor 202 receives the insurance value received by the communication control section, and renew the insurance value in the memory device 221 (step 956 ).", "[0077] According to the fourth embodiment of the present invention, the driving information can be stored in the storing device 224 together with the remaining insurance value, as in case of the first embodiment.", "Also, the insurance value may be renewed by transmitting the calculated insurance value to the memory device 221 in real time.", "[0078] The following is a description of another embodiment (hereinafter, referred to as a “fifth embodiment”;", "no flow chart is shown in the drawings) of the present invention.", "According to the fifth embodiment, the driving information is inputted from a driving information sensor attached to a vehicle to calculate the remaining insurance value in the first through the fourth embodiments of the present invention, and is recorded in the card 106 , a storing device 224 or in the memory device 221 .", "The stored driving information and the remaining insurance value are periodically (e.g., once every month) read out by the microprocessor 202 and transmitted to the server of the insurance company via a wire or wireless telecommunication terminal.", "Otherwise, the driver may transmit the stored driving information and the remaining insurance value to the server of the insurance company through an access thereto on an irregular basis.", "Also, when the remaining insurance value has a predetermined value (e.g., below 10% of the subscribed insurance value), the microprocessor 202 recognizes the value, and transmits the driving information and the remaining insurance value to the server of the insurance company The server of the insurance company transmits a phrase, etc.", "requiring a renewal of the insurance value on the display section 218 of the insurance processing device of the present invention.", "[0079] When the server of the insurance company requires the recorded information through communication between the microprocessor 202 and the server of the insurance company, the microprocessor 202 reads out and transmits the pertinent information to the server of the insurance company.", "[0080] The server of the insurance company may make the information as a database related to an insurance subscription.", "The server of the insurance company transmits the remaining insurance value and record of use, etc.", "to the driver based on the information via E-mail, an internet terminal, or the display section 218 of the insurance processing device of the present invention.", "[0081] As described above, the present invention realizes a rational automobile insurance system by paying an insurance fee according to an actual driving time or distance rather than according to a period of insurance.", "Since the insurance fee is paid depending on the driving of a vehicle, the practice of unnecessary driving can be particularly avoided by utilizing present invention, thereby contributing to the energy policy and the transportation policy as well as to an environment in reducing the pollution.", "Further, driving with excessive speed can be prevented and traffic accidents can be reduced by discriminatingly imposing the insurance fee according to driving velocities.", "Moreover, purchasing and recharging the card for paying the insurance fee also serve for saving the expenses and user convenience.", "[0082] While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims." ]
FIELD OF THE INVENTION This invention is in the field of apparatus and methods for mounting viewing aids in vehicles, such as complementary apparatus associated with a rear-view mirror. CROSS REFERENCE TO RELATED APPLICATIONS The present invention is related to application Ser. No. 07/453,581 as an apparatus and method to facilitate use of the invention of the referenced application. BACKGROUND OF THE INVENTION In a separate invention known to the present inventor an optical magnification unit is provided for selectively viewing to the rear for vehicle operators. The viewing unit is a telescopic device called a "Magniscope" using a lenses and internal mirrors, and lets an operator view selected fields to the rear of the vehicle in magnification. The internal mirrors provide an optical path length consistent with the focal length of optics in the Magniscope. Because the Magniscope views to the rear of a vehicle and an operator looks to the front, another reflection of what the Magniscope "sees" is needed for the magnified image to be useful to the vehicle operator. To minimize costs for the Magniscope and to maximize its utility, a mounting apparatus and method is needed to incorporate the Magniscope with existing internal rear-view mirrors. By doing so, much of the original function of the existing rear-view mirror is retained, space is saved, the complexity and cost of the Magniscope is minimized, and the windshield area of the vehicle is less obstructed than might be the case otherwise. There are also situations in vehicles where mounting to an existing mirrr is not practical, for example in a van or a truck where only outside mirrors may be used, and there is no central rearview mirror. A way to use a magniscope in this instance is needed, and in some situations, a hand-held device may be useful. There are devices known in the art that may also usefully be incorporated in a mounting system for a Magniscope, such as other utility mirrors and radar detection devices. SUMMARY OF THE INVENTION In a preferred embodiment an apparatus is provided for mounting a complementary device to a rear-view mirror of a vehicle. The apparatus has an adjustably opposed clamp with an upper portion and a lower portion, the upper portion for engaging the top and the lower for engaging the bottom of a rear-view mirror. A support extends from the clamp and supports a pivotal mount at the end opposite the clamp to engage a complementary device to be mounted to the mirror. In a preferred embodiment the support is a rod fixed to a portion of the clamp, and a collar with a post engages the rod and is rotatable about the rod to position the post vertically. The complementary device has a bore to engage the post. The mounting provides for positioning the device to be mounted in a horizontal plane and allows the device to be aimed independently of the mirror position. In the preferred embodiment the clamp is configured to span the adapter by which the rear-view mirror is attached to the inside of a vehicle. In an alternative preferred embodiment the support is rotatable where it is attached to the clamp, so the pivotal mount need not be rotatable about the support. In another alternative preferred embodiment a universal joint is joined to the support, and the device is mounted to the universal joint. In yet another embodiment the support is joined to the clamp by a universal joint, and a second universal joint mounts the device at the other end of the support. This embodiment has the advantage of being movable to not interfere with use of a passenger-side visor. A method is provided in the invention for damping vibration by preloading the assembly between the rear-view mirror and the device, or between the rear-view mirror and the mounting apparatus. The damping pre-loading is also made adjustable to compensate for varying conditions of vibration. Finally an embodiment is provided for the device to be hand held, either on a platform configured for that purpose, or by applying necessary components to the case of the device. The invention provides for mounting a device, such as a magnifying viewing device for looking to the rear of a vehicle, to the inside of the vehicle to be of maximum use to an operator, and also for using such a device by holding in the hand when needed. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a mounting apparatus according to a preferred embodiment of the invention. FIG. 2 is a plan view showing a complementary device mounted to a rear-view mirror using a mounting apparatus according to the invention. FIG. 3 is a perspective view of an apparatus according to an alternative embodiment of the invention. FIG. 4 is a plan view showing a device mounted using the apparatus according to FIG. 3. FIG. 5 is a perspective view showing an apparatus according to the invention with a ball joint on a post for mounting a device. FIG. 6 is a perspective view showing an apparatus according to a preferred embodiment using two ball joints. FIG. 7 is a perspective view showing an apparatus according to a preferred embodiment with a clamp configured to span the adapter for a rear-view mirror. FIG. 8 is a plan view showing the apparatus of FIG. 7 mounted to a rear-view mirror. FIG. 9 is a plan view showing the use of resilient springs to dampen vibration in an embodiment of the invention. FIG. 10 is a perspective view showing a holder for a radar detector mounted to the apparatus of the invention. FIG. 11 shows a platform with a handle and auxiliary mirror according to an alternative preferred embodiment of the invention. FIG. 12 shows the embodiment of FIG. 11 with a device mounted to the platform. FIG. 13 shows an embodiment similar to that of FIG. 11 and 12 using the case of the mounted device. FIG. 14 shows a hand-held device according to a preferred embodiment of the invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partially exploded perspective view of a mounting apparatus 11 according to a preferred embodiment of the invention, for adapting a complementary device such as Magniscope to an existing rear-view mirror in a vehicle. In this preferred embodiment the mounting apparatus has a clamp consisting of an upper portion 13 and a lower portion 15, adjustably opposed by screws 25 and 27 passing pivotally through lower portion 15 and engaging threaded bores in upper portion 13. Threading from below is preferable, as the screw heads are more easily accessible from below when attaching the apparatus to a rear-view mirror. In the preferred embodiment the screws are of the locking type with a nylon or other polymer insert to avoid loosening in operation. Alternatively screws and nuts may be used or shafts fixed in one portion and engaged by set screws in the other. A person with skill in the art will see that there are many equivalent ways to oppose the portions and secure the clamp. In the preferred embodiment shown in FIG. 1 the upper and lower clamp portions have lips 14 and 16 respectively to help retain the clamp in the rear-view mirror. The length of the fastening arrangement is such that the clamp may be made to span mirrors of many different sizes. Height D1 is adjustable from about 5 cm. in height to about 10 cm. The depth of the clamp D2 is about 2 cm. to be deep enough to engage most existing rear-view mirrors. The depth can be made smaller or greater in different embodiments of the invention, if needed. A round support extension 17 extends from the lower clamp portion in the preferred embodiment, and a collar 12 with a locking screw 18 has a mounting post 19 for mounting a complementary device such as the Magniscope. The collar may be moved along the support extension and rotated about the extension to position the mounting for the device. It is not, of course, absolutely required that extension 17 extend from the lower clamp portion, it could, in some cases, extend from the upper portion. Extension 17 can be a molded part of the clamp portion from which it extends, or may attach by threaded engagement, force fit in a bore, or by other methods known in the art. In the preferred embodiment the body portions of the apparatus are injection molded of a suitable polymeric material, such as polycarbonate, although there are other suitable materials, and the body parts could also be metal molded or machined. In the preferred embodiment shown in FIG. 1 flexible pads such as pads 29 and 31 are affixed to the inside surfaces of the clamp by gluing or other suitable technique. Similar pads are affixed inside the upper portion, but not seen in FIG. 1. The pads help avoid damage to a rear-view mirror and also help to damp vibration that might be troublesome. FIG. 2 is a plan view of a rear-view mirror 33 on a conventional adapter 35 attached to an inside surface of a vehicle, with a mounting apparatus 11 according to the embodiment shown in FIG. 1 clamped to the mirror, and a Magniscope 37 is shown mounted on the mounting apparatus. The Magniscope in this example has an extension 39 with a bore 41 for engaging post 19. In this preferred embodiment bore 41 in extension 39 is slightly longer than the length of post 19, and a threaded cap 21 (shown in FIG. 1, but not shown in FIG. 2)) engages a threaded bore 22 in the top end of post 19 to clamp extension 39 between the cap and collar 12. Before the cap is secured, the Magniscope can be rotated about post 19 to align the scope to "see" a particular area behind the vehicle. Moreover, collar 12 may be moved along extension 17 and rotated around extension 17 to aid in positioning and aiming the Magniscope. In alternative embodiments the scope is secured to the post in other ways, such as by a set screw through extension 39 into bore 41 to bear against post 19. With such a set screw mounting, the Magniscope may also be adjusted vertically along the length of post 19. FIG. 2 illustrates some important aspects of the invention relative to the mounting and aiming of devices such as the Magniscope described. The plan view of FIG. 2 is arranged so that line 40 is substantially "straight ahead" relative to the vehicle. Because in most vehicles with an unobstructed rear window, the mirror is mounted substantially at the center of the front windshield, the mirror, for the driver to use it properly, is nomally tilted somewhat toward the driver as indicated in the Figure. Also, the mirror is usually mounted somewhat above the eye level of the driver, to leave the view forward through the windshield relatively unobstructed. For this reason the plane of the reflective surface is usually tilted downward as well. Most conventional mirror mounts have a ball joint type mounting as indicated by element 36 to accomplish this tilting. The Magniscope, however, needs to be aimed horizontally to the rear, and to be rotatable about a vertical axis to aim at different positions behind the vehicle, such as different lanes of traffic. For this to be so, with a post mounting for rotation as shown in FIG. 1, the post needs to be substantially vertical while the plane of the mirror is tilted downward and toward the driver. Rotation of collar 12 about extension 17 allows a driver to position the mirror and then to adjust the mounting post to be vertical for best operation of the Magniscope. Moving collar 12 along support extension 17 allows a driver to position the magnified image on the rear-view mirror without substantially changing the aiming of the Magniscope to the rear. A certain amount of adjustment of position in the left-to-right horizontal direction relative to the driver is beneficial for positioning the image on the rear-view mirror. Experience has shown that the movement needed is over a range of about 1 inch. It is true that the embodiment of FIG. 1 to work effectively, the lengthwise axis of the mirror need be maintained substantially horizontal, so post 19 is not rotated away from horizontal in a plane not correctable b rotating collar 12. This, however, is relatively easy to do, as the rear-view mirror works to maximum effect when the horizontal axis of the mirror is maintained horizontal relative to the vehicle. Alternatively to the arrangement shown in FIGS. 1 and 2, the round support extension can be rotatable in a bore in the lower (or upper) clamp portion, and the collar can be fixed to the support extension. There are other equivalent ways that the mounting can be rotatable relative to the clamp so a mounted device can be adjusted without disturbing the position of the rear view mirror, or readjusted after changing the position of the rear-view mirror. With the Magniscope aimed along line 43 as shown in FIG. 2, the magnified image is projected along line 45 and reflected from the mirror along line 47. Note that line 43 is not necessarily parallel with line 45. This is a function of the design of the Magniscope. Also, line 47 is not necessarily the line along which a driver normally looks to use the rear-view mirror. In the best preferred adjustment, line 47 passes to the right of a driver's normal eye position, and the driver can thus use the rear-view mirror with maximum effect without obstruction from the Magniscope. When the driver wants a magnified image via the magniscope, he or she leans a little to the right to intercept line 47, and thus gains a magnified image of a selected lane or field behind the vehicle. FIG. 3 is a perspective view of a mounting apparatus 51 in an alternative preferred embodiment of the invention, with a rigid support extension 53 extending from the lower clamp portion supporting a mounting post 55. In this embodiment post 55 cannot be normally maintained in a vertical position because of necessary adjustment of the plane of the reflective surface of the rear-view mirror. To compensate, a sliding clamp 57 with a clamp screw is provided to engage post 55, and a rocking arm 61 engages a slot 63 in the sliding clamp, and is held by the same clamp screw 59. Holes 63 and 65 are for attaching to a mounting pad (not shown) on a Magniscope or other complementary device. Clamp 57 can be moved along post 55 (arrow 67) to adjust the height of a device and rotated about post 55 (arrow 69) to adjust the aim to the rear. Rocking arm 61 can be rotated in slot 63 (arrow 71) to adjust the magniscope or other mounted device for level. FIG. 4 is a plan view of the embodiment shown by FIG. 3 showing a Magniscope 37 attached to rocking arm 61. In this embodiment there are sufficient degrees of freedom to position the Magniscope to be level, as required, and to adjust the aim to select different fields to the rear. To do so requires (after the mirror position is adjusted to the driver's requirement), both rotating clamp 57 about post 55, which may not be vertical, and rotating rocker arm 61 about the axis of clamp screw 59. FIG. 5 shows yet another apparatus according to an alternative preferred embodiment of the invention incorporating a ball joint mechanism 75 positioned on a post 77 attached to a support extension 79 extending from a lower portion of a clamp. The ball joint mechanism has a ball 81 on post 77, a ball nut 83, and a ball cap 85 with a mounting pad 87 for attaching to a Magniscope or other complementary device. A person with skill in the art will recognize that there are many equivalent ways that a ball joint may be provided on the post and attached to a complementary device such as the Magniscope. With the apparatus of FIG. 5, the mirror can be adjusted to the requirements of the driver, and the Magniscope can then be positioned properly without altering the mirror adjustment. FIG. 6 shows yet another apparatus 89 according to an alternative preferred embodiment of the invention. Mounting apparatus 89 has a support arm 91 extending from a first ball joint 93 attached to a portion of the clamp and a second ball joint 95 at the opposite end of the support arm. The second ball joint has a mounting pad 97 for mounting a Magniscope or other complementary device. Ball joint 95 is shown exploded in FIG. 6 to illustrate a ball 99, a cap 101, and a nut 103. The cap has a mounting pad 97 for attaching to a Magniscope or other complementary device. The apparatus of FIG. 6 has a particular advantage in that the support arm can be swilveled at the first ball joint to move a mounted device away from the passenger side visor to allow the visor to be adjusted. The first ball joint is shown in FIG. 6 attached to the lower portion of the clamp, but could also be attached to the upper portion, and could be attached to either portion at other positions than at the center of the portion. In the embodiments described above, the clamp is designed to engage the rear-view mirror at one side of the adapter by which the mirror mounts to an inside surface of the vehicle, such as the inside of the windshield. In all of these embodiments, the clamp may also be configured to span the mirror's adapter. Spanning the center adapter of the mirror has the advantage of reducing the cantilevered weight on the mirror, which in some cases provides a more stable mounting. FIG. 7 shows the mounting apparatus of FIG. 5 with openings 105 and 107 in the upper and lower portions respectively of the clamp, so the clamp can mount to the mirror by spanning the center adapter for the mirror. The apparatus of FIG. 7 has a support arm 109 shown broken, because a longer support arm is needed with the center mounting. Also, when configured to span the center adapter for the rear-view mirror, the opening to clear the adapter needs to have about one-half inch clearance on each side (openings 105 and 107 need to provide sufficient clearance) so the apparatus can be moved along the mirror in each direction left and right, to aid in positioning the magnified image on the rear-view mirror for a particular driver. FIG. 8 is a top view of an apparatus similar to the apparatus of FIGS. 3 and 4, but having a clamp configured to span the center adapter and a support arm 111 longer than the support arm 53 of the apparatus of FIG. 3. In building and testing apparatus according to the invention it has been found that preloading is useful to dampen vibration. FIG. 9 is a plan view of a mounting apparatus according to the invention with a leaf spring 115 to preload the assembly to dampen vibration. The leaf spring, also called a whisker, is fixedly mounted to the complementary device 37 such as by a fastener 117. Alternatively, the leaf spring may be mounted to the mounting post as shown in dotted outline 119. The free end of the leaf spring urges against the front surface of the glass reflector of the rear-view mirror, providing a force to dampen vibration that tends to blur the image. It has also been found to be helpful to be able to adjust the force exerted by the spring. In the case of fastening the spring to the complementary device such as by a fastener 117, the spring can be slotted where the fastener penetrates the spring so the spring position can be moved to adjust the preloading. In the case of mounting the leaf spring to the post, there are a number of alternative ways that the rotative position of the spring relative to the post can be adjusted and held after adjustment. The spring can be mounted to a cylinder with a set screw, for example. There are also many other ways to preload the assembly other than by providing a leaf spring. Coil springs can be used, for example, and flexible members made of rubber-like materials. FIG. 10 is a perspective view showing another alternative preferred embodiment 121 of the invention. In this embodiment a rotatable holder 123 is attached to the underside of the lower portion of the clamp by a single fastener (not shown) such that the holder may be rotated about a vertical axis as center of rotation. The rotatable holder is for holding a radar detector 125 shown in dotted outline. By rotating the holder the radar detector can be aimed to the front of the vehicle in an adjustable line. The radar detector, the rear magnifier, and the rear-view mirror may be aimed to provide maximum utility for each. There are, of course, a number of equivalent ways that a holder for a radar detector may be attached, and there are many ways that a holder may be constructed to hold a detector. For example, the holder may also be joined to the clamp member by a universal joint, such as a ball joint, so the direction of the radar detector may be adjusted independently of the position of the rear-view mirror. FIG. 11 shows an alternative preferred embodiment of the invention that does not attach to a rear-view mirror. In this embodiment a platform 127 has a handle 129 mounted to the underside and a mirror 131 mounted to the topside. The platform also has mounting clips such as clip 133 attached to the topside by conventional fasteners, for holding a Magniscope. FIG. 12 shows a Magniscope mounted to the platform. In this embodiment of the invention a Magniscope of the same type and manufacture that is mounted to the mounting apparatus in the other embodiments may also be mounted to platform 127. It will be apparent to one with skill in the art that there are many equivalent ways a Magniscope may be mounted to the platform, such as with conventional fasteners such as screws. The mounting clips shown in FIG. 11 are convenient. The platform could also be provided with a post, and the Magniscope mounted to the post similar to mountings shown in other embodiments. An advantage of the embodiment shown in FIGS. 11 and 12 is that the device may be conveniently stored on the seat next to the driver, in a rack (not shown) on or under the dashboard, or even in the glove box. The driver can pick up the device when needed and hold it to view a magnified image to the rear. FIG. 13 shows yet another embodiment of the invention in which the hand-held mounting is a part of the case of the Magniscope. Handle 133 may be attached to the case of the Magniscope by fasteners or integrally molded. Mirror 135 is similarly attached to the case or a mounting for the mirror may be integrally molded to the case. FIG. 14 shows another preferred embodiment similar to the embodiment of FIG. 13, but eliminating the handle. In the embodiment shown by FIG. 14, a user holds the Magniscope in a hand much as one holds a camcorder, grasping the case by area 137. The case may be molded to provide a comfortable and secure grip. The protruding handle is in some cases convenient, but not really needed, and the device is more compact and storable without the handle. A person will skill in the art will recognize that there are many variations that may be made without departing from the spirit and scope of the invention. Some of these variations have already been mentioned, such as several different ways that the assembly may be preloaded to dampen vibration effects. The apparatus of the invention may vary considerably from the dimensions described, and there is a wide choice of suitable materials that may be used for the different elements of the invention. There are similarly many other variations that do not depart significantly from the spirit and scope of the invention.
A mounting device with a clamp and pivotal holders provides mounting to a vehicular rear-view mirror for complementary devices such as a magnification scope or a radar detection device. Hand-held mounting is provided as well.
Briefly summarize the main idea's components and working principles as described in the context.
[ "FIELD OF THE INVENTION This invention is in the field of apparatus and methods for mounting viewing aids in vehicles, such as complementary apparatus associated with a rear-view mirror.", "CROSS REFERENCE TO RELATED APPLICATIONS The present invention is related to application Ser.", "No. 07/453,581 as an apparatus and method to facilitate use of the invention of the referenced application.", "BACKGROUND OF THE INVENTION In a separate invention known to the present inventor an optical magnification unit is provided for selectively viewing to the rear for vehicle operators.", "The viewing unit is a telescopic device called a "Magniscope"", "using a lenses and internal mirrors, and lets an operator view selected fields to the rear of the vehicle in magnification.", "The internal mirrors provide an optical path length consistent with the focal length of optics in the Magniscope.", "Because the Magniscope views to the rear of a vehicle and an operator looks to the front, another reflection of what the Magniscope "sees"", "is needed for the magnified image to be useful to the vehicle operator.", "To minimize costs for the Magniscope and to maximize its utility, a mounting apparatus and method is needed to incorporate the Magniscope with existing internal rear-view mirrors.", "By doing so, much of the original function of the existing rear-view mirror is retained, space is saved, the complexity and cost of the Magniscope is minimized, and the windshield area of the vehicle is less obstructed than might be the case otherwise.", "There are also situations in vehicles where mounting to an existing mirrr is not practical, for example in a van or a truck where only outside mirrors may be used, and there is no central rearview mirror.", "A way to use a magniscope in this instance is needed, and in some situations, a hand-held device may be useful.", "There are devices known in the art that may also usefully be incorporated in a mounting system for a Magniscope, such as other utility mirrors and radar detection devices.", "SUMMARY OF THE INVENTION In a preferred embodiment an apparatus is provided for mounting a complementary device to a rear-view mirror of a vehicle.", "The apparatus has an adjustably opposed clamp with an upper portion and a lower portion, the upper portion for engaging the top and the lower for engaging the bottom of a rear-view mirror.", "A support extends from the clamp and supports a pivotal mount at the end opposite the clamp to engage a complementary device to be mounted to the mirror.", "In a preferred embodiment the support is a rod fixed to a portion of the clamp, and a collar with a post engages the rod and is rotatable about the rod to position the post vertically.", "The complementary device has a bore to engage the post.", "The mounting provides for positioning the device to be mounted in a horizontal plane and allows the device to be aimed independently of the mirror position.", "In the preferred embodiment the clamp is configured to span the adapter by which the rear-view mirror is attached to the inside of a vehicle.", "In an alternative preferred embodiment the support is rotatable where it is attached to the clamp, so the pivotal mount need not be rotatable about the support.", "In another alternative preferred embodiment a universal joint is joined to the support, and the device is mounted to the universal joint.", "In yet another embodiment the support is joined to the clamp by a universal joint, and a second universal joint mounts the device at the other end of the support.", "This embodiment has the advantage of being movable to not interfere with use of a passenger-side visor.", "A method is provided in the invention for damping vibration by preloading the assembly between the rear-view mirror and the device, or between the rear-view mirror and the mounting apparatus.", "The damping pre-loading is also made adjustable to compensate for varying conditions of vibration.", "Finally an embodiment is provided for the device to be hand held, either on a platform configured for that purpose, or by applying necessary components to the case of the device.", "The invention provides for mounting a device, such as a magnifying viewing device for looking to the rear of a vehicle, to the inside of the vehicle to be of maximum use to an operator, and also for using such a device by holding in the hand when needed.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a mounting apparatus according to a preferred embodiment of the invention.", "FIG. 2 is a plan view showing a complementary device mounted to a rear-view mirror using a mounting apparatus according to the invention.", "FIG. 3 is a perspective view of an apparatus according to an alternative embodiment of the invention.", "FIG. 4 is a plan view showing a device mounted using the apparatus according to FIG. 3. FIG. 5 is a perspective view showing an apparatus according to the invention with a ball joint on a post for mounting a device.", "FIG. 6 is a perspective view showing an apparatus according to a preferred embodiment using two ball joints.", "FIG. 7 is a perspective view showing an apparatus according to a preferred embodiment with a clamp configured to span the adapter for a rear-view mirror.", "FIG. 8 is a plan view showing the apparatus of FIG. 7 mounted to a rear-view mirror.", "FIG. 9 is a plan view showing the use of resilient springs to dampen vibration in an embodiment of the invention.", "FIG. 10 is a perspective view showing a holder for a radar detector mounted to the apparatus of the invention.", "FIG. 11 shows a platform with a handle and auxiliary mirror according to an alternative preferred embodiment of the invention.", "FIG. 12 shows the embodiment of FIG. 11 with a device mounted to the platform.", "FIG. 13 shows an embodiment similar to that of FIG. 11 and 12 using the case of the mounted device.", "FIG. 14 shows a hand-held device according to a preferred embodiment of the invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partially exploded perspective view of a mounting apparatus 11 according to a preferred embodiment of the invention, for adapting a complementary device such as Magniscope to an existing rear-view mirror in a vehicle.", "In this preferred embodiment the mounting apparatus has a clamp consisting of an upper portion 13 and a lower portion 15, adjustably opposed by screws 25 and 27 passing pivotally through lower portion 15 and engaging threaded bores in upper portion 13.", "Threading from below is preferable, as the screw heads are more easily accessible from below when attaching the apparatus to a rear-view mirror.", "In the preferred embodiment the screws are of the locking type with a nylon or other polymer insert to avoid loosening in operation.", "Alternatively screws and nuts may be used or shafts fixed in one portion and engaged by set screws in the other.", "A person with skill in the art will see that there are many equivalent ways to oppose the portions and secure the clamp.", "In the preferred embodiment shown in FIG. 1 the upper and lower clamp portions have lips 14 and 16 respectively to help retain the clamp in the rear-view mirror.", "The length of the fastening arrangement is such that the clamp may be made to span mirrors of many different sizes.", "Height D1 is adjustable from about 5 cm.", "in height to about 10 cm.", "The depth of the clamp D2 is about 2 cm.", "to be deep enough to engage most existing rear-view mirrors.", "The depth can be made smaller or greater in different embodiments of the invention, if needed.", "A round support extension 17 extends from the lower clamp portion in the preferred embodiment, and a collar 12 with a locking screw 18 has a mounting post 19 for mounting a complementary device such as the Magniscope.", "The collar may be moved along the support extension and rotated about the extension to position the mounting for the device.", "It is not, of course, absolutely required that extension 17 extend from the lower clamp portion, it could, in some cases, extend from the upper portion.", "Extension 17 can be a molded part of the clamp portion from which it extends, or may attach by threaded engagement, force fit in a bore, or by other methods known in the art.", "In the preferred embodiment the body portions of the apparatus are injection molded of a suitable polymeric material, such as polycarbonate, although there are other suitable materials, and the body parts could also be metal molded or machined.", "In the preferred embodiment shown in FIG. 1 flexible pads such as pads 29 and 31 are affixed to the inside surfaces of the clamp by gluing or other suitable technique.", "Similar pads are affixed inside the upper portion, but not seen in FIG. 1. The pads help avoid damage to a rear-view mirror and also help to damp vibration that might be troublesome.", "FIG. 2 is a plan view of a rear-view mirror 33 on a conventional adapter 35 attached to an inside surface of a vehicle, with a mounting apparatus 11 according to the embodiment shown in FIG. 1 clamped to the mirror, and a Magniscope 37 is shown mounted on the mounting apparatus.", "The Magniscope in this example has an extension 39 with a bore 41 for engaging post 19.", "In this preferred embodiment bore 41 in extension 39 is slightly longer than the length of post 19, and a threaded cap 21 (shown in FIG. 1, but not shown in FIG. 2)) engages a threaded bore 22 in the top end of post 19 to clamp extension 39 between the cap and collar 12.", "Before the cap is secured, the Magniscope can be rotated about post 19 to align the scope to "see"", "a particular area behind the vehicle.", "Moreover, collar 12 may be moved along extension 17 and rotated around extension 17 to aid in positioning and aiming the Magniscope.", "In alternative embodiments the scope is secured to the post in other ways, such as by a set screw through extension 39 into bore 41 to bear against post 19.", "With such a set screw mounting, the Magniscope may also be adjusted vertically along the length of post 19.", "FIG. 2 illustrates some important aspects of the invention relative to the mounting and aiming of devices such as the Magniscope described.", "The plan view of FIG. 2 is arranged so that line 40 is substantially "straight ahead"", "relative to the vehicle.", "Because in most vehicles with an unobstructed rear window, the mirror is mounted substantially at the center of the front windshield, the mirror, for the driver to use it properly, is nomally tilted somewhat toward the driver as indicated in the Figure.", "Also, the mirror is usually mounted somewhat above the eye level of the driver, to leave the view forward through the windshield relatively unobstructed.", "For this reason the plane of the reflective surface is usually tilted downward as well.", "Most conventional mirror mounts have a ball joint type mounting as indicated by element 36 to accomplish this tilting.", "The Magniscope, however, needs to be aimed horizontally to the rear, and to be rotatable about a vertical axis to aim at different positions behind the vehicle, such as different lanes of traffic.", "For this to be so, with a post mounting for rotation as shown in FIG. 1, the post needs to be substantially vertical while the plane of the mirror is tilted downward and toward the driver.", "Rotation of collar 12 about extension 17 allows a driver to position the mirror and then to adjust the mounting post to be vertical for best operation of the Magniscope.", "Moving collar 12 along support extension 17 allows a driver to position the magnified image on the rear-view mirror without substantially changing the aiming of the Magniscope to the rear.", "A certain amount of adjustment of position in the left-to-right horizontal direction relative to the driver is beneficial for positioning the image on the rear-view mirror.", "Experience has shown that the movement needed is over a range of about 1 inch.", "It is true that the embodiment of FIG. 1 to work effectively, the lengthwise axis of the mirror need be maintained substantially horizontal, so post 19 is not rotated away from horizontal in a plane not correctable b rotating collar 12.", "This, however, is relatively easy to do, as the rear-view mirror works to maximum effect when the horizontal axis of the mirror is maintained horizontal relative to the vehicle.", "Alternatively to the arrangement shown in FIGS. 1 and 2, the round support extension can be rotatable in a bore in the lower (or upper) clamp portion, and the collar can be fixed to the support extension.", "There are other equivalent ways that the mounting can be rotatable relative to the clamp so a mounted device can be adjusted without disturbing the position of the rear view mirror, or readjusted after changing the position of the rear-view mirror.", "With the Magniscope aimed along line 43 as shown in FIG. 2, the magnified image is projected along line 45 and reflected from the mirror along line 47.", "Note that line 43 is not necessarily parallel with line 45.", "This is a function of the design of the Magniscope.", "Also, line 47 is not necessarily the line along which a driver normally looks to use the rear-view mirror.", "In the best preferred adjustment, line 47 passes to the right of a driver's normal eye position, and the driver can thus use the rear-view mirror with maximum effect without obstruction from the Magniscope.", "When the driver wants a magnified image via the magniscope, he or she leans a little to the right to intercept line 47, and thus gains a magnified image of a selected lane or field behind the vehicle.", "FIG. 3 is a perspective view of a mounting apparatus 51 in an alternative preferred embodiment of the invention, with a rigid support extension 53 extending from the lower clamp portion supporting a mounting post 55.", "In this embodiment post 55 cannot be normally maintained in a vertical position because of necessary adjustment of the plane of the reflective surface of the rear-view mirror.", "To compensate, a sliding clamp 57 with a clamp screw is provided to engage post 55, and a rocking arm 61 engages a slot 63 in the sliding clamp, and is held by the same clamp screw 59.", "Holes 63 and 65 are for attaching to a mounting pad (not shown) on a Magniscope or other complementary device.", "Clamp 57 can be moved along post 55 (arrow 67) to adjust the height of a device and rotated about post 55 (arrow 69) to adjust the aim to the rear.", "Rocking arm 61 can be rotated in slot 63 (arrow 71) to adjust the magniscope or other mounted device for level.", "FIG. 4 is a plan view of the embodiment shown by FIG. 3 showing a Magniscope 37 attached to rocking arm 61.", "In this embodiment there are sufficient degrees of freedom to position the Magniscope to be level, as required, and to adjust the aim to select different fields to the rear.", "To do so requires (after the mirror position is adjusted to the driver's requirement), both rotating clamp 57 about post 55, which may not be vertical, and rotating rocker arm 61 about the axis of clamp screw 59.", "FIG. 5 shows yet another apparatus according to an alternative preferred embodiment of the invention incorporating a ball joint mechanism 75 positioned on a post 77 attached to a support extension 79 extending from a lower portion of a clamp.", "The ball joint mechanism has a ball 81 on post 77, a ball nut 83, and a ball cap 85 with a mounting pad 87 for attaching to a Magniscope or other complementary device.", "A person with skill in the art will recognize that there are many equivalent ways that a ball joint may be provided on the post and attached to a complementary device such as the Magniscope.", "With the apparatus of FIG. 5, the mirror can be adjusted to the requirements of the driver, and the Magniscope can then be positioned properly without altering the mirror adjustment.", "FIG. 6 shows yet another apparatus 89 according to an alternative preferred embodiment of the invention.", "Mounting apparatus 89 has a support arm 91 extending from a first ball joint 93 attached to a portion of the clamp and a second ball joint 95 at the opposite end of the support arm.", "The second ball joint has a mounting pad 97 for mounting a Magniscope or other complementary device.", "Ball joint 95 is shown exploded in FIG. 6 to illustrate a ball 99, a cap 101, and a nut 103.", "The cap has a mounting pad 97 for attaching to a Magniscope or other complementary device.", "The apparatus of FIG. 6 has a particular advantage in that the support arm can be swilveled at the first ball joint to move a mounted device away from the passenger side visor to allow the visor to be adjusted.", "The first ball joint is shown in FIG. 6 attached to the lower portion of the clamp, but could also be attached to the upper portion, and could be attached to either portion at other positions than at the center of the portion.", "In the embodiments described above, the clamp is designed to engage the rear-view mirror at one side of the adapter by which the mirror mounts to an inside surface of the vehicle, such as the inside of the windshield.", "In all of these embodiments, the clamp may also be configured to span the mirror's adapter.", "Spanning the center adapter of the mirror has the advantage of reducing the cantilevered weight on the mirror, which in some cases provides a more stable mounting.", "FIG. 7 shows the mounting apparatus of FIG. 5 with openings 105 and 107 in the upper and lower portions respectively of the clamp, so the clamp can mount to the mirror by spanning the center adapter for the mirror.", "The apparatus of FIG. 7 has a support arm 109 shown broken, because a longer support arm is needed with the center mounting.", "Also, when configured to span the center adapter for the rear-view mirror, the opening to clear the adapter needs to have about one-half inch clearance on each side (openings 105 and 107 need to provide sufficient clearance) so the apparatus can be moved along the mirror in each direction left and right, to aid in positioning the magnified image on the rear-view mirror for a particular driver.", "FIG. 8 is a top view of an apparatus similar to the apparatus of FIGS. 3 and 4, but having a clamp configured to span the center adapter and a support arm 111 longer than the support arm 53 of the apparatus of FIG. 3. In building and testing apparatus according to the invention it has been found that preloading is useful to dampen vibration.", "FIG. 9 is a plan view of a mounting apparatus according to the invention with a leaf spring 115 to preload the assembly to dampen vibration.", "The leaf spring, also called a whisker, is fixedly mounted to the complementary device 37 such as by a fastener 117.", "Alternatively, the leaf spring may be mounted to the mounting post as shown in dotted outline 119.", "The free end of the leaf spring urges against the front surface of the glass reflector of the rear-view mirror, providing a force to dampen vibration that tends to blur the image.", "It has also been found to be helpful to be able to adjust the force exerted by the spring.", "In the case of fastening the spring to the complementary device such as by a fastener 117, the spring can be slotted where the fastener penetrates the spring so the spring position can be moved to adjust the preloading.", "In the case of mounting the leaf spring to the post, there are a number of alternative ways that the rotative position of the spring relative to the post can be adjusted and held after adjustment.", "The spring can be mounted to a cylinder with a set screw, for example.", "There are also many other ways to preload the assembly other than by providing a leaf spring.", "Coil springs can be used, for example, and flexible members made of rubber-like materials.", "FIG. 10 is a perspective view showing another alternative preferred embodiment 121 of the invention.", "In this embodiment a rotatable holder 123 is attached to the underside of the lower portion of the clamp by a single fastener (not shown) such that the holder may be rotated about a vertical axis as center of rotation.", "The rotatable holder is for holding a radar detector 125 shown in dotted outline.", "By rotating the holder the radar detector can be aimed to the front of the vehicle in an adjustable line.", "The radar detector, the rear magnifier, and the rear-view mirror may be aimed to provide maximum utility for each.", "There are, of course, a number of equivalent ways that a holder for a radar detector may be attached, and there are many ways that a holder may be constructed to hold a detector.", "For example, the holder may also be joined to the clamp member by a universal joint, such as a ball joint, so the direction of the radar detector may be adjusted independently of the position of the rear-view mirror.", "FIG. 11 shows an alternative preferred embodiment of the invention that does not attach to a rear-view mirror.", "In this embodiment a platform 127 has a handle 129 mounted to the underside and a mirror 131 mounted to the topside.", "The platform also has mounting clips such as clip 133 attached to the topside by conventional fasteners, for holding a Magniscope.", "FIG. 12 shows a Magniscope mounted to the platform.", "In this embodiment of the invention a Magniscope of the same type and manufacture that is mounted to the mounting apparatus in the other embodiments may also be mounted to platform 127.", "It will be apparent to one with skill in the art that there are many equivalent ways a Magniscope may be mounted to the platform, such as with conventional fasteners such as screws.", "The mounting clips shown in FIG. 11 are convenient.", "The platform could also be provided with a post, and the Magniscope mounted to the post similar to mountings shown in other embodiments.", "An advantage of the embodiment shown in FIGS. 11 and 12 is that the device may be conveniently stored on the seat next to the driver, in a rack (not shown) on or under the dashboard, or even in the glove box.", "The driver can pick up the device when needed and hold it to view a magnified image to the rear.", "FIG. 13 shows yet another embodiment of the invention in which the hand-held mounting is a part of the case of the Magniscope.", "Handle 133 may be attached to the case of the Magniscope by fasteners or integrally molded.", "Mirror 135 is similarly attached to the case or a mounting for the mirror may be integrally molded to the case.", "FIG. 14 shows another preferred embodiment similar to the embodiment of FIG. 13, but eliminating the handle.", "In the embodiment shown by FIG. 14, a user holds the Magniscope in a hand much as one holds a camcorder, grasping the case by area 137.", "The case may be molded to provide a comfortable and secure grip.", "The protruding handle is in some cases convenient, but not really needed, and the device is more compact and storable without the handle.", "A person will skill in the art will recognize that there are many variations that may be made without departing from the spirit and scope of the invention.", "Some of these variations have already been mentioned, such as several different ways that the assembly may be preloaded to dampen vibration effects.", "The apparatus of the invention may vary considerably from the dimensions described, and there is a wide choice of suitable materials that may be used for the different elements of the invention.", "There are similarly many other variations that do not depart significantly from the spirit and scope of the invention." ]
CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 14/031,700 entitled “Protective Enclosure for Electronic Device,” filed Sep. 19, 2013, which is a continuation of U.S. patent application Ser. No. 12/560,621 entitled “Protective Enclosure for Electronic Device,” filed Sep. 16, 2009, which is a division of U.S. patent application Ser. No. 11/456,157 entitled “Protective Enclosure for Electronic Device,” filed Jul. 7, 2006 (now U.S. Pat. No. 7,609,512), which is a continuation-in-part of U.S. patent application Ser. No. 10/937,048 entitled “Protective Enclosure for an Interactive Flat-Panel Controlled Device,” filed Sep. 8, 2004 (now U.S. Pat. No. 7,158,376), which is a continuation-in-part of U.S. patent application Ser. No. 10/645,439 entitled “Protective Membrane for Touch Screen Device,” filed Aug. 20, 2003 (now U.S. Pat. No. 6,995,976), which is a continuation of U.S. patent application Ser. No. 10/300,200 entitled “Protective Case for Touch Screen Device,” filed Nov. 19, 2002 (now U.S. Pat. No. 6,646,864), which claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 60/335,865 filed Nov. 19, 2001 entitled “Protective Case for Touch Screen Device.” The entire contents of the above mentioned applications and patents are hereby specifically incorporated by reference in their entirety. BACKGROUND OF THE INVENTION Portable electronic devices (PEDs), such as PDAs, computers, MP3 players, music players, video players, smart phones, GPS receivers, telematics devices, cell phones, satellite phones, pagers, monitors, etc., are being very widely used, and are being deployed in industrial as well as office environments. PEDs are being used in industrial environments for data collection, such as service information on an airplane, or for data delivery such as maps for fire fighters and other emergency personnel. When PEDs are deployed in such industrial applications, the data that is collected and displayed on the PED can be extremely valuable and can be lifesaving. The industrial environments impose harsh conditions that typical PEDs are not designed to accommodate. For example, damage can be done to the PED through rough handling and dropping. Further, industrial chemicals, grease, water, dirt, and grime may damage or destroy a functioning PED and inhibit the use of the PEDs valuable data. It is common to hold the PEDs inside a protective case for transport. However, PEDs are usually removed for use since most cases used for transport are not interactive. Interactive cases are also useful for non-industrial applications to provide protection for PEDs. SUMMARY OF THE INVENTION A protective enclosure for an electronic device is provided. The protective enclosure includes a first case member, a second case member, a rigid plunger, and an electrical conductor. The second case member is hingeably attached to the first case member to form a shell that includes a watertight enclosure for the electronic device. The rigid plunger is adapted to transmit a mechanical motion from outside the shell to the electronic device inside the shell. The electrical conductor includes an electrical plug to mate to an electrical jack of the electronic device in the watertight enclosure to electrically connect the electronic device to a device outside the shell. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, FIG. 1 is a perspective view of an embodiment of the invention shown in the closed position. FIG. 2 is a perspective view of an embodiment of the invention shown in the open position. FIG. 3 is a perspective view of an embodiment of the invention shown in an exploded state. FIG. 4 is a perspective view of an embodiment of the invention shown from the rear. FIG. 5 is a front view of an embodiment of the invention, showing a section line. FIG. 6 is a section view of an embodiment of the invention. FIG. 7 is a detailed view of a section shown in FIG. 6 . FIG. 8 is a perspective view of another embodiment comprising a single piece encapsulating cover. FIG. 9 is a perspective view of a third embodiment comprising a non-encapsulating snap over cover. FIG. 10 is a perspective view of an embodiment that comprises a belt clip. FIG. 11 is a second perspective view of an embodiment that comprises a belt clip. FIG. 12 is a perspective view of another embodiment of the present invention of a protective cover for a PED or other device. FIG. 13A is a perspective top view of another embodiment of a protective enclosure for a tablet PC. FIG. 13B is a view of the protective enclosure lid of FIG. 13A . FIG. 14 is a perspective top view of the embodiment of FIG. 13A with an open lid. FIG. 15 is a perspective bottom view of the embodiment of FIG. 13A . FIG. 16 is a perspective view of the base of the embodiment of FIG. 13A FIG. 17 is an exploded view of an embodiment of a protective enclosure for an interactive flat-panel controlled device. FIG. 18 is an exploded view of another embodiment of a protective enclosure for an interactive flat-panel controlled device. FIG. 19 is an exploded view of another embodiment of a protective enclosure with an open lid for a laptop computer device. FIG. 20 is an exploded view of a protective enclosure with an open lid for a laptop computer device positioned inside the enclosure. FIG. 21 is a perspective top view of a protective enclosure with a closed lid for a laptop computer device. FIG. 22 is a perspective bottom view of the protective enclosure FIG. 21 . FIG. 23 is a perspective front view of the embodiment of FIG. 21 . FIG. 24 is a perspective end view of the embodiment of FIG. 21 . FIG. 25 is a perspective back view of the embodiment of FIG. 21 . FIG. 26 is a perspective view of the USB hub. FIG. 27 is a perspective view of the USB hub mounted inside the enclosure of FIG. 21 . FIG. 28 is a perspective view of the USB hub mounted inside the enclosure of FIG. 14 . DETAILED DESCRIPTION FIG. 1 is a perspective view of an embodiment of the invention. Embodiment 100 comprises a rigidly molded front case 102 and rear case 104 . An overmolded grommet 106 forms a receptacle for stylus 108 and also aids in sealing membrane 110 . A flexible hand strap 112 attaches to the rear case 104 . A hinge 114 joins front case 102 and rear case 104 . A ring 124 for a lanyard is shown as an integral feature of rear case 104 . Embodiment 100 is designed to hold a conventional personal digital assistant (PED) in a protective case. A PED, such as a Palm Pilot, Handspring Visor, Compaq Ipaq, Hewlett Packard Jornada, or similar products, use a touch screen for display and data entry. The touch screen display comprises either a color or black and white liquid crystal display with a touch sensitive device mounted on top of the display. The display is used for displaying graphics, text, and other elements to the user. The touch screen is used with a stylus 108 to select elements from the screen, to draw figures, and to enter text with a character recognition program in the PED. The stylus 108 generally resembles a conventional writing implement. However, the tip of the writing implement is a rounded plastic tip. In place of a stylus 108 , the user may use the tip of a finger or fingernail, or a conventional pen or pencil. When a conventional writing implement is used, damage to the touch screen element may occur, such as scratches. For the purposes of this specification, the term PED shall include any electronic device that has a touch screen interface. This may include instruments such as voltmeters, oscilloscopes, logic analyzers, and any other hand held, bench top, or rack mounted instrument that has a touch screen interface. Hand held devices, such as cell phones, satellite phones, telemetric devices, and other hand held devices are also to be classified as PEDs for the purposes of this specification. The term PED shall also include any computer terminal display that has a touch screen interface. These may comprise kiosks, outdoor terminal interfaces, industrial computer interfaces, commercial computer interfaces, and other computer displays. Additionally, the term PED may comprise barcode scanners, hand held GPS receivers, and other handheld electronic devices. The foregoing description of the term PED has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and other modifications and variations may be possible in light of the teachings of this specification. In addition, the PEDs typically have a handful of additional buttons as part of the user interface. These buttons are generally on the front of the device, near the touch screen element. The additional buttons may be used as shortcut buttons to instantly call up a certain program on the PED, may comprise a method of scrolling, may be used to select items from a list, or may have any function that the designer of the PED software may assign to the button or set of buttons. The button size, layout, and function may vary for each manufacturer and model of PED. Further, PEDs typically have at least one method of connecting to another computer. This may be through a direct electrical connection, such as through a wire cable or fiber optic, or through another medium such as infrared communication or through a radio communication. Additionally, the PEDs typically have an electrical source. The electrical source may be a rechargeable or non-rechargeable battery or solar cells. The electrical source may be a remote source of electricity that is transmitted to the PED through a wire cable or through other methods of electrical transmission. Further, PEDs may have indicator lights, such as status lights for power, communication, battery status, or other functions. The lights may be located on any of the sides of the PED and may be viewable on one or more sides. Front case 102 and rear case 104 form a protective cover for the PED. The protective cover may be designed for rugged industrial use, recreational use, commercial use, or many other uses. An industrial use may require the protective cover to be watertight, chemically resistant, protect the unit when dropped, and be crush proof. A typical application may be for fire fighters to use a PED for a display of maps for directions to an emergency scene or for a building plan at the scene of a fire. Another example may be a maintenance mechanic in a chemical plant using a PED to record maintenance records in the plant that processes. A recreational use may require the cover to be watertight, afford some protection against dropping and being crushed, float in water, and be dust resistant. A recreational use may be to take the PED during kayaking, diving, or other water sport activity. Further, the case may be used when the PED is taken camping, hiking, or other outdoor activity. A commercial use may additionally require the protective cover to be elegant, but may also require the cover to be replaceable so that scratches and other signs of wear and tear can be easily and cheaply replaced. The protective cover for the PED may take on many embodiments. The embodiment 100 comprises a front case 102 and rear case 104 that are joined by a hinge 114 and a clasp mechanism that is on the side of the cases opposite the hinge 114 . Other embodiments may have a small door into which the PED slides, or the protective cover may not completely enclose the PED and only cover the face where the user interface exists, leaving one or more sides of the PED exposed. Those skilled in the art may use other designs of protective covers without deviating from the scope and intent of the present invention. The protective cover may be constructed of rigid plastic, metal, flexible rubber, or any other type of material that could be adapted to afford the protection of the PED desired for the application. For example, a metal cover may be used in an application where an elegant style is necessary but watertightness is not. A flexible rubber cover may be selected for an application in a wet environment. A rigid plastic cover may be selected for an application where dropping the PED is a concern. Those skilled in the art may use other types of materials and constructions without deviating from the spirit of the present invention. The PED may be mounted in the protective cover using many different mounting techniques. For example, the PED may be mounted using open or closed cell foam inserts in the protective cover. In another embodiment, the PED may be mounted by attaching the PED to the cover with a fastener. In another embodiment, the PED may be mounted by snapping into the protective waterproof cover. In another embodiment, the PED may be held in place by resting in molded features of two halves of a protective case that clamps onto the PED. Those skilled in the art may use other types of locating and holding mechanisms without deviating from the spirit of the present invention. The overmolded grommet 106 of the present embodiment is constructed by injection molding a thermoplastic polymerized rubber (TPR) over the front case 102 . The grommet 106 has molded features 116 and 118 adapted to retain the stylus 108 . Features 116 and 118 capture the stylus 108 during transportation, but allow the user to remove the stylus 108 to operate the PED. In other embodiments of the present invention, the stylus 108 may be constrained to the PED with a tether or lanyard, or the constraining features may be incorporated into other components that make up the protective cover. Further, the stylus 108 may not be present in the embodiment, rather, the PED be adapted to be used with the user's fingernail or with another implement similar to the stylus 108 . The membrane 110 of the present embodiment is constructed by thermoforming a sheet of thin plastic. The plastic is selected to be thin enough that the deformation of a stylus conducts the touch to the touch screen, but thick enough to have enough rigidity that the stylus does not catch and rip the membrane. Additionally, the membrane 110 should have enough thickness to endure scratches and other wear and tear without breaking and sacrificing the protective function. Polyvinylchloride material at 0.010 inches to 0.015 inches thickness gives acceptable results. Alternatively, membrane 110 may be constructed by injection molding or other methods. Alternative materials may be used by those skilled in the art to achieve the same results while maintaining within the spirit and intent of the present invention. The membrane 110 in the present embodiment may be translucent or at least partially transparent, so that the images displayed on the PED may be visible through the membrane 110 . The membrane 110 may be tinted or colorized in some applications. For example, a protective cover designed as a decorative cover may incorporate a colorized membrane 110 . Further, the membrane may be selectively colorized and the opaqueness may vary. For example, the protective membrane may be printed or painted in the areas not used for the touch screen. A printing process may incorporate a logo, graphics, or labeling for individual buttons for the PED. The printing process may further incorporate features, such as text or graphics, that are used by the software on the PED for a purpose such as simplifying data input or for designating an area on the touch screen for a specific function, such as a help function. The printing or painting processes used on the membrane 110 may be purely decorative and may be for aesthetic purposes only. The printing process may also comprise logos or graphics for the brand identity of the PED cover. Other processes, such as colorizing the raw material for the membrane 110 or adding other components to the raw material, such as metal flakes or other additives, may be used to change the optical features of the membrane 110 . The optical performance of the membrane 110 may be changed or enhanced by changing the texture of the area of the touch screen. For example, the membrane may be frosted on the outside to hide scratches or may be imprinted with a lens or other features that change the optical characteristics of the membrane 110 . The membrane 110 may have optical features that are used in conjunction with the software of the PED. For example, all or a portion of the membrane may comprise a lens that magnifies an image to a user. When the user touches the image on the membrane 110 and the touch is transferred to the touch screen, the software in the PED may have to compensate for the positional differences between the image and actual area that was touched by the user. In another example, if a specific portion of the membrane 110 had a specific optical characteristic, the software of the PED may be constructed to display a specific graphic for the area for an intended effect. The membrane 110 in the present embodiment has a recessed portion 120 and a raised portion 122 . The recessed portion 120 may be adapted to press flat against the touch screen area of a specific PED. The raised portion 122 may be adapted to fit over an area of the specific PED where several buttons are located. The raised portion 122 allows the user to operate the buttons on the PED. The raised portion 122 is adapted such that the buttons on the PED are easily operated through the protective membrane 110 . The raised portion 122 may have special features to aid the user in pressing the buttons. For example, the raised portion 122 may comprise a dimpled area for the user's finger located directly over the button. Further, a feature to aid the user may comprise a section of membrane 110 defined by a thinner area around the section, enabling the user to more easily deflect the section of membrane over the button. The area of thinner material may comprise a large section or a thin line. Further, tactile elements, such as small ribs or bumps may be incorporated into the membrane 110 in the area of the buttons so that the user has a tactile sensation that the user's finger is over the button. The tactile element may be particularly effective if the button was a power switch, for example, that turned on the PED. The configuration of the membrane 110 may be unique to each style or model of PED, however, the front case 102 and rear case 104 may be used over a variety of PEDs. In the present embodiment, the changeover from one PED variety to another is accomplished by replacing the membrane 110 without having to change any other parts. The present embodiment may therefore be mass-produced with the only customizable area being the membrane 110 to allow different models of PEDs to be used with a certain front case 102 and rear case 104 . The hand strap 112 in the present embodiment allows the user to hold the embodiment 100 securely in his hand while using the PED. The hand strap 112 may be constructed of a flexible material, such as rubber or cloth webbing, and may have an adjustment, such as a buckle, hook and loop fastener, or other method of adjustment. In other embodiments, a hand strap may be a rigid plastic handle, a folding handle, or any other method of assisting the user in holding the embodiment. Further, the embodiment may be adapted to be fix-mounted to another object, like a piece of machinery, a wall, or any other object. A fix-mounted embodiment may have other accoutrements adapted for fixed mount applications, such as receptacles for a stylus adapted to a fix-mount, specialized electrical connections, features for locking the PED inside the case to prevent theft, or designs specifically adapted to shed water when rained upon. FIG. 2 illustrates a perspective view of the embodiment 100 shown in an open position. The front case 102 and rear case 104 are shown open about the hinge 114 . Membrane 110 is shown installed into gasket 106 , and the recessed portion 120 and raised portion 122 of membrane 110 is illustrated looking from the inside of the case. The clasp mechanisms are not shown in this illustration. Hand strap 112 is shown attached to rear case 104 . FIG. 3 illustrates a perspective view of the embodiment 100 shown in an exploded state. The hand strap 116 attaches to the rear cover 104 . The overmolded grommet 106 holds the stylus 108 and is attached to front cover 102 . The membrane 110 attaches to the grommet 106 and is held in place with an o-ring 302 . FIG. 4 illustrates a perspective view of the embodiment 100 shown from the rear. The hand strap 116 is shown, along with rear cover 104 and front cover 102 . The stylus 108 is shown inserted into the overmolded grommet 106 . FIG. 5 illustrates a top view of the embodiment 100 . The front cover 102 , membrane 110 , stylus 108 , and hinge 114 are all visible. FIG. 6 illustrates a section view of the embodiment 100 taken through the section line shown in FIG. 5 . The front cover 102 , rear cover 104 , overmolded gasket 106 , stylus 108 , membrane 110 , hand strap 112 , and o-ring 302 are all shown hatched in this view. FIG. 7 illustrates a detail view of the embodiment 100 shown in FIG. 6 . Front case 102 and rear case 104 are joined at hinge 114 . Overmolded gasket 106 traps membrane 110 and o-ring 302 locks membrane 110 in place. Overmolded gasket 106 may be formed by molding thermoplastic polymerized rubber over the front cover 102 . The replacement of the membrane 110 is accomplished by removing o-ring 302 , pushing the membrane 110 from the overmolded gasket 106 , snapping a new membrane 110 into place, and replacing the o-ring 302 . The ease of replacement of the present embodiment allows a user to quickly replace a damaged membrane 110 , allows a user to upgrade their case to a newer model PED, and may allow a user to select from various membranes 110 for the particular application. One embodiment may have a single case packaged with a small variety of several types of membranes 110 . In such an embodiment, the user may purchase the packaged set, select the membrane 110 that suits the user's particular PED, and install the selected membrane 110 with ease. The protective cover of the present invention may have direct connections through the cover for connecting through the case. Such a connection is known as pass through. The connections may be for power, communication, heat dissipation, optical transmissions, mechanical motion, or other reasons. Electrical connections may require an insulated metal conductor from the PED through the wall of the protective cover so that a flexible cable may be attached or so that the PED in its protective case may be placed in a cradle for making the electrical connection. Inside the protective cover, the electrical connections may be made with a flexible cable that is plugged into the PEDs electrical connector before the PED is secured in the protective cover. Alternatively, a fixed connector may be attached to the protective cover and the PED is slid into contact with the fixed connector. Another embodiment may be for a compliant, yet fixed mounted electrical connector to be rigidly mounted inside the protective cover. A compliant, yet fixed mounted electrical connector 1830 may comprise spring loaded probes, commonly referred to as pogo pins. Another embodiment may comprise spring fingers that engage the PEDs electrical contacts. On the outside of the protective cover, the electrical contacts may be terminated into a fix-mounted connector adapted to receive a cable from a computer. The connector may be designed to receive a cable that plugs directly into the PED or it may be adapted to receive a different connector. Further, the electrical connection to the PED may be permanently attached to a cable that extends out of the protective cover. Another embodiment may be to have a small trap door that opens in the protective cover to allow access to the electrical connections. While the trap door exposes the PED to the elements the cover is designed to protect against, a direct electrical connection may eliminate a potential cabling connection problem. Connections for fiber optics can be handled in similar fashions as the electrical connections. An embodiment with a power connection may comprise the use of inductive coils, such as inductive coil 1840 , located in proximity to each other but on opposite sides of the protective cover. Those skilled in the art of may devise other embodiments for connecting through the protective cover without deviating from the scope and intent of the present invention. Through the air communications, such as infrared and over the air radio frequency (RF) communications may pass through the protective cover. The material for the front case 102 and rear case 104 may be selected to be clear plastic, such as polycarbonate. The infrared transceiver of the PED can communicate through a clear plastic case to another infrared transceiver outside of the case. Further, the appropriate selection of material for the protective case can thereby enable various RF transmissions, such as cellular phone communications or other wireless communication protocols. An infrared transmission through the protective case of an embodiment of the invention may be accomplished by making the entire protective case out of a clear material. Alternatively, a selected area of the protective case may be clear while the remainder of the case is opaque. The selected area may be constructed of a separate piece that allows the infrared light through the protective case. Alternatively, the selected area may be constructed of a portion of the protective case that was manufactured in a way so as not to be opaque, such as selectively not painting or plating the area of a plastic protective case. Further, the clear material through which the transmission occurs may be tinted in the visual spectrum but be translucent or at least partially transparent in the infrared spectrum of the device. A protective case may allow RF transmissions to and from the PED while the case is closed. Such a case may be constructed of a non-metallic material. In some embodiments, the material of the protective case may be tuned to allow certain frequencies to pass through the protective cover and tune out other frequencies, through loading the material used in the protective cover with conductive media or through varying the thickness of the case and other geometries of the case in the area of the PED transmission and reception antenna. In a different embodiment, it may be desirable to shield the PED from outside RF interference. In this case, the protective cover may be a metallic construction or may be plastic with a metallized coating. Further, membrane 110 may have a light metallized coating applied so that membrane 110 is slightly or fully conductive. An application for such an embodiment may be the use of the PED in an area of high RF noise that may interfere with the operation of the PED, or conversely, the use may be in an area that is highly susceptible to external RF interference and the PEDs RF noise may be interfering with some other device. The PED may be equipped with a camera or other video capture device. A protective cover may have provisions to allow a clear image to be seen by the video capture device through the case. Such provisions may include an optically clear insert assembled into the protective case. Other embodiments may have a sliding trap door whereby the user of the PED may slide the door open for the camera to see. Additionally, other embodiments may comprise a molded case that has an optically clear lens integrally molded. Such an embodiment may be additionally painted, plated, or overmolded, with the lens area masked so that the painting, plating, or overmolding does not interfere with the optics of the lens. An optically clear area may be used for a barcode scanner portion of a PED to scan through the case to the outside world. In such an embodiment, a barcode scanner may be protected from the elements while still maintaining full functionality in the outside world. The PED may have indicator lights that indicate various items, such as power, battery condition, communication, and other status items. The indicator lights may be in positions on the PED that are not readily viewable through the protective membrane 110 . The indicator lights may be made visible through the protective case by using light pipes that transmit the light from the PEDs status light to the outside of the protective case. Such light pipes may be constructed of clear or tinted plastic, or other translucent or semi-transparent material. The light pipes may be formed as an integral feature to the protective case or may be separate parts that are formed separately and assembled to the protective case. The PED may have a speaker or other element that makes noise and/or the PED may have a microphone for receiving audio signals. The speaker may be an audio quality device for reproducing sound or it may be a simple buzzer for indicating various functions of the PED. The microphone may be an audio quality device or it may be a low performance device. Special provisions may be made for transmitting sound through a protective case. Such provisions may range from a single hole in the case to a tuned cavity that would allow sound to pass through with minimum distortion. Other embodiments may include a transmissive membrane adapted to allow sound to pass through the protective case with a minimum of distortion. Such membranes may be located near the speaker and microphone elements of the PED. Such membranes may be watertight membranes known by the brand name Gore-Tex. The PED may generate heat during its use and provisions for dissipating the heat may be built into the protective cover. A heat-dissipating device may be integral to the protective cover or may comprise one or more separate parts. For example, a metallic protective cover may be adapted to touch the PED in the area of heat generation and conduct the heat outwardly to the rest of the protective cover. The protective cover may thereby dissipate the heat to the external air without overheating the PED. In another example, a separate heat sink may be applied to the PED and allowed to protrude through a hole in the protective cover. The heat sink may thereby transfer the heat from the PED to the ambient environment without overheating the PED. The heat sinks may be attached to the PED with a thermally conductive adhesive. Other embodiments may include vent holes for heat dissipation and air circulation. The PED may have a button that may not be located underneath the membrane 110 . An embodiment may include a flexible, pliable, or otherwise movable mechanism that may transmit mechanical motion from the outside of the case to a button on the PED. Such an embodiment may have a molded dimpled surface that is pliable and allows a user to activate a button on a PED by pressing the dimpled surface. Another embodiment may have a rigid plunger that is mounted on a spring and adapted to transmit the mechanical movement from the exterior of the case to a button on the PED. The buttons on the PED may be located on any side of the PED and an embodiment of a case may have pliable areas adapted to allow the user to press buttons that are not on the front face of the PED. FIG. 8 is an illustration of embodiment 800 of the present invention wherein the PED 802 is encapsulated by a protective cover 804 . The installation of the PED 802 is to slide PED 802 into the opening 808 , then fold door 806 closed and secure with flap 810 , which is hinged along line 812 . Areas 814 and 816 may comprise a hook and loop fastener system or other fastening device. Recessed area 818 is adapted to fit against touch screen 820 of PED 802 . Embodiment 800 may be comprised of a single molded plastic part that may be very low cost. As shown, embodiment 800 may not be completely weathertight, since the door 806 does not completely seal the enclosure. However, such an embodiment may afford considerable protection to the PED 802 in the areas of dust protection, scratch protection, and being occasionally rained upon. Further, the low cost of the embodiment 800 may be changed often during the life of the PED 802 . Embodiment 800 may have custom colors, logos, or designs that allow a user to personalize their PED with a specific cover that is suited to their mood or tastes. The colors, logos, and designs may be integrally molded into the cover 804 . Alternatively, different colors, logos, and designs may be applied in a secondary operation such as printing, painting, plating, or other application process. FIG. 9 is an illustration of embodiment 900 of the present invention wherein a decorative cover 902 is snapped over a PED 904 . The ends 906 and 908 snap over the PED ends 910 and 912 as an attachment mechanism for cover 902 to PED 904 . Recessed area 914 is adapted to fit against touch screen 916 . Embodiment 900 may be a cover for decorative purposes only, or may be for protective purposes as well. Cover 902 may be emblazoned with logos, designs, or other visual embellishments to personalize the PED 904 . The colors, logos, and designs may be integrally molded into the cover 904 . Alternatively, different colors, logos, and designs may be applied in a secondary operation such as printing, painting, plating, or other application process. Embodiment 900 may be attached by snapping the cover 902 onto PED 904 . Special provisions in the case of PED 904 may be provided for a snapping feature of cover 902 , or cover 902 may be adapted to hold onto PED 904 without the use of special features in PED 904 . The features used to secure cover 902 to PED 904 may be any mechanism whereby the cover 902 can be secured. This includes snapping, clamping, fastening, sliding, gluing, adhering, or any other method for securing two components together. FIG. 10 illustrates a perspective view of an embodiment of a receiver 1002 for holding the protective case 100 . The protective case 100 is held into receiver 1002 in such a manner that the touch screen display is facing into the receiver 1002 , to afford the touch screen display with protection. FIG. 11 illustrates a perspective view of the embodiment of a receiver 1002 shown from the opposite side as FIG. 10 . Receiver 1002 is comprised of a back 1102 , a belt clip mechanism 1104 , and four clip areas 1106 , 1108 , 1110 , and 1112 . The protective case 100 is placed into the receiver 1002 by inserting one end into the receiver, then rotating the protective case 100 into position such that the snapping action of clip areas 1106 , 1108 , 1110 , and 1112 are engaged to hold protective case 100 securely. Receiver 1002 may be adapted to clip onto a person's belt or may be adapted to be mounted on a wall or other location where the PED may be stored. The orientation of the protective case 100 is such that the touch screen element of the PED is protected during normal transport and storage, since the touch screen interface is facing the back 1102 of the receiver 1002 . Receiver 1002 may be made of compliant plastic that allows the clip areas 1106 , 1108 , 1110 , and 1112 to move out of the way and spring back during insertion or removal of the protective case 100 . In the present embodiment, receiver 1002 may be constructed of a single part. In alternative embodiments, receiver 1002 may be constructed of multiple parts and of multiple materials, such as a metal back with spring loaded clips. In other embodiments, special features may be included in the protective case 100 where the receiver 1002 may engage a special feature for securing the protective case 100 . FIG. 12 illustrates an embodiment 1200 of the present invention of a protective cover for a PED or other device. A rigid front cover 1202 and a rigid rear cover 1204 are held together with a series of latches 1206 , 1208 , 1210 , and 1212 . The protective membrane 1214 protects the touchscreen of the enclosed PED. A folding rigid cover 1216 operates as a rigid shield to prevent the membrane 1214 from any damage. The stylus holder 1220 is formed from an overmolded flexible material in which the membrane 1214 is mounted. Embodiment 1200 illustrates yet another embodiment of the present invention wherein a rigid protective cover may be used to contain and protect an electronic device, but provide full usable access to a touchscreen. The protective membrane 1214 and case may be watertight in some embodiments. FIG. 13A illustrates an embodiment of a protective enclosure 1300 that encloses and protects a tablet PC 1302 . PEDs that have touch screens, as described above, have an interactive flat-panel control, i.e., the touch screen display. Tablet PCs are portable electronic computing devices that have a high-resolution interactive flat-panel control that accepts smooth stylus strokes such as handwriting. The embodiment of FIG. 13A is crush-resistant, impact-resistant, watertight, and simultaneously allows interactive stylus strokes and other sensitive user inputs to be accurately and easily transmitted through a protective screen membrane 1306 to the interactive flat-panel control of tablet PC 1302 . A watertight and shock-absorbing foam cushion 1310 may be fixed and sealed to the underside of the lid 1304 around the interactive flat-panel control opening. The protective screen membrane 1306 is fixed and sealed to the shock-absorbing foam cushion 1310 . The shock-absorbing foam cushion 1310 maintains the water tightness of the enclosure. The cushion 1310 also cushions the flat-panel control of the tablet PC 1302 and protects it against breakage if the enclosure and tablet PC are dropped or otherwise subjected to shock. In accordance with the embodiment of FIG. 13A , the shock-absorbing foam cushion 1310 has a thickness of approximately 0.25 inches and extends approximately 0.060 inches below the underside of the interactive flat-panel control opening of the lid 1304 . One source of suitable watertight shock-absorbing foam is E.A.R. Specialty Composites of 7911 Zionville Rd., Indianapolis, Ind., 46268. Cushion 1310 allows the protective screen membrane to move a distance of up to 0.125 inches during an impact to the enclosure or when pressure is applied to protect membrane 1306 while pushing the tablet PC control buttons 1308 or writing on the interactive flat-panel control with a stylus through the membrane. The shock-absorbing foam cushion 1310 also pushes the protective screen membrane 1306 flatly against the surface of the interactive flat-panel control of the tablet PC 1302 so that sensitive user stylus strokes and other inputs are accurately transmitted. The pressure of the cushion 1310 on the protective screen membrane 1306 which holds the protective screen membrane 1306 flatly against the interactive flat-panel control of the tablet PC 1302 also keeps display images, viewed through the protective screen membrane, clear and distortion-free. In embodiments of the protective enclosure to protect a touch-screen device, the protective membrane may be adjacent to the touch screen but does not exert mechanical pressure on the touch screen so that mechanical inputs such as style strokes are sensed only when intended. In embodiments of the protective enclosure to protect a tablet PC that has an RF stylus or to protect a handheld device that a capacitance-sensing interactive flat-panel control, the protective membrane may be pressed flat against the interactive flat-panel control which allows undistorted viewing but does not adversely affect the control since the interactive control uses capacitance or radio frequencies for interactive input instead of mechanical pressure. The protective screen membrane 1306 in the embodiment of FIG. 13A is at least partially transparent and has a thickness of approximately 0.010 inches. The thickness of the protective screen membrane 1306 should be typically in the range of 0.001 inches to 0.020 inches so that stylus strokes on the upper surface of protective screen membrane 1306 are transmitted accurately to the interactive flat-panel control of the tablet PC 1302 . Likewise, protective screen membrane 1306 may be flexible or semi-rigid and may be made of polyvinylchloride or other suitable transparent thermoplastic, such as, for example, polyvinylchloride, thermoplastic polycarbonate, thermoplastic polypropylene, thermoplastic acrylonitrile-butadiene-styrene, thermoplastic polyurethane, which has a hardness and texture that permits the stylus to smoothly glide across the surface without skipping, grabbing, or catching against the surface. Some tablet PCs utilize a stylus which transmits strokes to the PC by way of radio frequency transmission. Protective screen membrane 1306 may be made of a rigid, clear, engineered thermoplastic such as, for example, thermoplastic polycarbonate or other thermoplastics as described above, for enclosing a tablet PC. A protective screen membrane 1306 that is rigid may include watertight access ports that allow operation of mechanical buttons or switches of the tablet PC 1302 , such as, for example, control buttons 1308 . The watertight access ports may include holes that have a moveable watertight plug, or any type of watertight button or lever. Protective screen membrane 1306 may include an anti-glare coating or can be made with an anti-glare texture so that display images are clearly viewable without distortion through the protective screen membrane 1306 . In the embodiment of FIG. 13A , the lid 1304 of the protective enclosure 1300 may have an external stylus holder 1324 that securely holds a stylus used with the tablet PC 1302 . As described above with respect to FIG. 1 , the lid 1304 and the base 1312 may have air-permeable watertight vents 1318 , 1326 that permit the cooling fans of the tablet PC 1302 to force air exchange to dissipate heat by convection so that the tablet PC 1302 does not overheat. Watertight vents 1318 , 1326 may comprise holes in the lid 1304 and base 1312 that are made watertight by covering and sealing the holes with an air-permeable watertight membrane such as, for example, a fabricated expanded polytetrafluoroethylene (ePTFE) membrane. One source of expanded polytetrafluoroethylene (ePTFE) membranes is W.L. Gore & Associates, Inc. of 555 Papermill Road, Newark, Del., 19711. The embodiment of FIG. 13A may also comprise a pod door 1322 that allows access to table PC interfaces such as, for example, PCMCIA or Smart Card slots. The pod door 1322 is attached to the lid 1304 so that it may be removed or opened. In the embodiment of FIG. 13A , the pod door 1322 is hingedly connected to a portion of the base 1312 at a location of the base 1312 that has an opening that allows access to the tablet PC interfaces. The opening can be covered by a watertight seal 1320 , such as, for example, an O-ring that is part of pod door 1322 . The underside of the lid 1304 also has a watertight seal, such as an O-ring, so that when compound latches 1328 , 1330 , 1332 , and 1334 are closed, the O-ring or seal of the lid 1304 forms a watertight seal against the base 1312 . The protective enclosure 1300 protects the tablet PC 1302 from water and dust intrusion sufficient to comply with Ingress Protection (IP) rating of IP 67 , i.e., the protective enclosure totally protects the enclosed tablet PC from dust and protects the enclosed tablet PC from the effects of immersion in one meter of water for 30 minutes. The protective enclosure of the embodiment of FIG. 13A may further comprise protective overmolding 1316 attached to the lid 1304 . A similar overmolding may be attached to the base 1312 . The protective overmolding 1316 may be made of material that is easily gripped in slippery conditions and provides additional shock absorption such as, for example, rubber or silicone. The protective overmolding 1316 extends above the surface of the lid in pre-determined areas to provide protrusions that are easily gripped even in slippery conditions. The protective enclosure of the embodiment of FIG. 13 may further comprise watertight plugs such as access port plug 1314 that fit snugly into openings in the base 1312 that provide access to various interfaces, connectors, and slots of the tablet PC 1302 . FIG. 13B illustrates a shell lid 1304 of the embodiment of FIG. 13A . Shell lid 1304 and base 1312 may be made of impact/crush resistant material such as glass-fiber reinforced engineered thermoplastic, such as for example, glass reinforced polycarbonate. Alternatively, the shell lid 1304 and shell base may be made of thermoplastic polycarbonate, thermoplastic polypropylene, thermoplastic acrylonitrile-butadiene-styrene, and thermoplastic compositions containing one or more thereof, or other engineered thermoplastics that provide a shock-resistant and impact resistant shell may be used. The engineered thermoplastics may be reinforced with glass fibers, carbon fibers, metal fibers, polyamide fibers, and mixtures thereof. Shell lid 1304 may be further reinforced with stiffeners 1334 , 1336 , 1338 , 1340 that are integrally embedded into the shell lid around the perimeter of an opening in the shell that is directly over the interactive flat-panel control portion of the tablet PC. The stiffeners may be made of steel or other hard material so that the stiffeners provide additional strength and prevent flexing of the lid 1304 which enhances the watertightness and the impact/crush resistance. FIG. 14 is an illustration of the embodiment of FIG. 13A with the lid 1404 detached from the base 1412 . To protect the tablet PC 1402 using the protective enclosure 1400 , the tablet PC 1402 is disposed to fit snugly into the base 1412 . The lid is oriented so that hooks 1436 , 1438 area aligned with pin 1440 that is connected to a portion of the base 1412 and the lid is closed so that hooks 1436 , 1438 are retained by pin 1440 . Compound latches 1428 , 1430 , 1432 , and 1434 are then snapped onto the lid so that the lid is compressed tightly against the base providing a watertight seal. FIG. 15 is a bottom view of the embodiment of FIG. 13 . The base 1516 of protective enclosure 1500 includes watertight vents such as watertight vent 1506 for air exchange to permit heat and sound dissipation from the enclosed tablet PC while at the same time maintaining watertightness. Pod release knobs 1512 , 1518 are attached to the base 1516 so that the knobs can be rotated clockwise to securely wedge against an edge of pod door 1522 to close the pod door 1522 tightly against a rim around the pod opening in base 1516 to create a watertight seal. Knobs 1512 , 1518 can be rotated counter-clockwise to release pod door 1522 to access the interfaces of the tablet PC covered by pod door 1522 . To provide additional protection against mechanical shock, heavy-duty corner bumpers such as bumper 1504 may be securely attached to the corners of base 1516 . As shown in FIG. 15 , an adjustable heavy-duty handle may be attached to the base 1516 of the protective enclosure 1500 to allow easy and reliable transportation of the protective enclosure 1500 that encloses a tablet PC. In some circumstances, it is convenient to hold the protective enclosure using hand strap 1514 that is made of strong slightly stretchable fabric. Hand strap 1514 attaches to four points of the base 1516 to that a user's hand or wrist can be inserted along the either the longer or shorted length on the protective enclosure 1500 and enclosure tablet PC. Hand strap 1514 may be made of neoprene or other strong stretchable material to securely hold the protective enclosure to the user's arm even in slippery conditions. The protective enclosure may further include a neck strap to provide a comfortable solution for using the tablet PC while standing. FIG. 16 illustrates a top view of the protective enclosure base 1600 . Watertight vents such as watertight vent 1616 allow air exchange for heat dissipation and sound transmission from an enclosed tablet PC. Seal rim 1614 is an integrally formed part of the protective enclosure 1600 which is compressed against an O-ring in the protective enclosure lid to provide a watertight seal when compound latches 1628 , 1630 , 1632 , and 1634 are closed onto the lid. Internal bumpers 1602 , 1604 , 1608 , 1610 attach to the interior corners of protective enclosure base 1600 to provide cushion and mechanical shock protection to an enclosed tablet PC. The L-shape and non-solid interior of internal bumpers 1602 , 1604 , 1608 , 1610 allows the bumpers to deflect and absorb the shock if the enclosed tablet PC is dropped or otherwise subjected to mechanical shock. The protective enclosure provides shock absorption sufficient to meet MIL-STD 810F, Method 516.5, Procedure 4, which is a Transit Drop Test. In the Transit Drop Test, the protective enclosure encloses a tablet PC or a mass equivalent to a tablet PC. The protective enclosure is sequentially dropped onto each face, edge, and corner for a total of 26 drops over plywood from a height of 48 inches. The protective enclosure is visually inspected after each drop and a functional check for leakage is performed after all drops are completed. Some tablet PCs have a docking connector disposed on the underside of the tablet PC so that the tablet PC can connect to power and signals. For example, emergency vehicles such as ambulances, fire trucks, or patrol cars, may have a docking station installed near the driver's seat onto which the driver may dock a tablet PC. The embodiment of protective enclosure base 1600 , as illustrated in FIG. 1 , may comprise a docking connector channel 1624 that is recessed with respect to the upper surface of the base that allows a docking connector to run from a docking connector that is disposed in the center underside of the tablet PC to access port 1626 . Alternatively, a docking pass-through connector 1620 may be made an integral and watertight part of the protective enclosure base 1600 so that the tablet PC docking connector attaches to the docking pass-through connector 1620 which, in turn, connects to the docking station in substantially the same manner as an unenclosed tablet PC. FIG. 17 illustrates another embodiment of protective enclosure 1700 for a handheld electronic device 1702 that has an interactive flat-panel control such as, but limited to, a capacitance-sensing interactive flat panel control, a touch screen or other interactive control. Handheld electronic devices that have an interactive flat-panel control benefit from being enclosed in a rugged protective enclosure that is crush-resistant, watertight, and shock-resistant and that simultaneously allows the user to interact with a sensitive interactive flat-panel control. Handheld electronic devices that have interactive flat-panel control may include music players, MP3 players, audio player/recorders, video players, computers, personal digital assistants (PDAs), GPS receivers, cell phones, satellite phones, pagers, monitors, etc. For example, Apple Computer Ipod is a popular handheld interactive device that plays MP3 or otherwise digitally-encoded music/audio. The Apple Ipod has an interactive flat-panel control in which a portion of the front panel is a flat-panel display and portion of the front panel is an interactive flat-panel control, called a touch wheel in some versions of the Ipod and click wheel in other versions of the Ipod, that has capacitive touch/proximity sensors. One function of such an interactive flat-panel control, i.e. touch wheel, is that the control can emulate a rotary control knob by sensing circular motion of a user's finger using capacitive sensors. The click wheel has the same function with the additional feature of sensing proximity of a user's finger and emulating button presses by a user's finger at pre-determined areas. In the embodiment of FIG. 17 , the shell lid 1706 and the shell base 1704 are made of polycarbonate or other engineered thermoplastics such as polyethylene, polypropylene, etc. that are crush-resistant and impact resistant. Shell base 1704 has a watertight seal 1718 , which may be an overmolded gasket, o-ring, liner or other seal that prevents water from entering the protective enclosure 1700 when the handheld interactive device 1702 is enclosed inside the protective enclosure 1700 . Shell base 1704 and shell lid 1706 may include watertight vents, electrical connectors, see-through areas or features as disclosed with respect to FIG. 1 . In the embodiment of FIG. 17 , shell lid 1706 includes apertures over predetermined portions of the handheld interactive device 1702 , such as the areas directly over the display screen 1714 and the interactive flat-panel control 1712 , or other designated areas, as desired. A protective screen membrane 1710 , that is at least partially transparent, is permanently or removably fixed in a watertight manner to the underside of shell lid 1706 in the aperture that is over the display screen 1714 . The protective screen membrane 1710 may be recessed with respect to the upper surface of the shell lid 1706 which provides protective elevated rim that protects the display screen 1714 from breakage. Protective screen membrane 1710 may be PVC, silicone, polyethylene or other material that is watertight and rugged. In the case that display screen 1714 is a touch screen, the protective screen membrane 1710 should be smooth enough and thin enough that stylus strokes and other inputs are transmitted accurately to the touch screen as disclosed above with respect to FIG. 1 , FIG. 12 , and FIG. 13 . Alternatively, it may be desirable not to have an aperture in shell lid 1706 for a protective membrane 1710 . In another embodiment, the shell lid 1706 can be made of a transparent material so that a transparent window can be formed in the shell lid 1706 in place of the protective screen membrane 1710 . The transparent window is aligned with the display screen 1714 so that the user can view the display screen 1714 . In this case, a protective elevated rim that is aligned with the display screen 1714 is not required in the shell lid 1706 to protect the display screen 1714 from damage since there is no protective screen membrane 1710 . If the display screen 1714 is a touch screen, the material of the shell lid 1706 that is aligned with the display screen 1714 to provide a window can be made thinner to allow the touch screen to properly operate. As also shown with respect to the embodiment of FIG. 17 , a protective control membrane 1708 is permanently or removably fixed in a watertight manner to the underside of shell lid 1706 in an aperture that is aligned with the interactive flat-panel control 1714 of the handheld device 1702 . The protective screen membrane 1710 is recessed with respect to the upper surface of the shell lid 1706 which provides protective elevated rim that protects the display screen 1714 from breakage and provides tactile feedback that guides a user's finger to the desired area, even in slippery conditions. Of course, the protective elevated rim may simply comprise the portion of the shell lid 1706 that is formed as a result of making an aperture in the shell lid 1706 and overmolding a protective touch-control membrane 1708 on an inside surface of the shell lid 1706 . In other words, the thickness of the shell lid 1706 creates a protective rim since the protective touch-control membrane 1708 is overmolded or otherwise attached to the back side of the shell lid 1706 . In that case, the rim is not elevated with respect to the surface of the shell lid 1706 , but rather, is elevated with respect to the membrane to form a protective rim. Interactive flat-panel control 1712 has capacitive sensors, which are part of a proximity/touch detector circuit. When a grounded object, such as a person's finger, which has free air capacitance of several hundred picofarads, is brought close to the capacitive sensors, the total capacitance measured by the detector circuit increases because the capacitance of the object with free air capacitance adds to the capacitance of the sensors since the total capacitance of two capacitors in parallel is additive. Multiple sensors may also be arranged so that movement of an object with free air capacitance can be detected, for example, movement of a person's finger in a circular motion analogous to turning a mechanical control knob. Some examples of interactive flat-panel controlled PEDs include Ipod and Ipod Mini music and audio players from Apple Computer. In some PEDs, such as the Apple Ipod, capacitive sensors may be disposed below a front panel made from a dielectric such as polycarbonate, which has a dielectric constant in the range of 2.2-3.8. In the embodiment of FIG. 17 , the protective control membrane 1708 is made of thin polycarbonate that is slightly flexible or other engineered thermoplastics that provide the rugged watertight protection and at the same time permit the capacitive sensors of the interactive flat-panel control 1712 to function correctly. Likewise, a protective control membrane 1708 with a dielectric constant that is too high may retain an electric charge long enough to reduce the response rate of the sensor to motion of a user's finger from one capacitive sensor zone of the interactive flat-panel control 1712 to another. A protective control membrane 1708 that is conductive or has a dielectric constant that is too low may diminish the sensitivity of the capacitive sensor by combining in series the capacitance of the protective membrane and the dielectric front panel of the PED which results in a lowering of the overall capacitance. Total capacitance between an object, such as a finger touching the protective control membrane 1708 , and interactive flat-panel control 1712 is a function of the thickness and the dielectric constant of the protective control membrane 1708 . The capacitance between the object, such as a finger, and the capacitive sensors of the interactive flat-panel control 1712 is proportional to the distance between the object and the sensors. The sensitivity of the capacitive sensors to the object may be diminished or completely eliminated if the protective control membrane 1708 is too thick. In the embodiment of FIG. 17 , the thickness of the protective control membrane is approximately 0.020 inches. The protective control membrane 1708 may be any thickness in the range of 0.003 inches to 0.020 inches that is adequate to provide a rugged watertight membrane through which capacitance can be correctly sensed by the interactive flat-panel control 1712 . The upper surface of the protective control membrane 1708 has a velvet/matte texture with a texture depth of 0.0004 to 0.003 inches that reduces the surface area of the membrane that is in frictional contact with the user's finger and permits a user's finger to glide rapidly upon the surface of the membrane without catching or sticking as a result of the reduced friction. The hardness of the polycarbonate material, or other hard engineered thermoplastic, also reduces the friction. Headphones or other accessories may be electrically connected to handheld device 1702 the through the protective enclosure 1700 by disposing the wire of the headphone or accessory in an insertable gasket 1716 which fits snugly into one end of the shell base 1704 . FIG. 18 illustrates another embodiment of protective enclosure 1800 which is substantially the same as protective enclosure 1700 of FIG. 17 . However, protective enclosure 1800 has an alternative electrical pass-through for accessories. In the embodiment of FIG. 18 , shell base 1804 includes an adapter cable 1816 that has an adapter plug 1812 at one end which plugs into a jack of handheld device 1802 . At the other end of the adapter cable 1816 is an adapter jack 1814 that is molded into, or otherwise integrally made part of, shell base 1804 . An external accessory, such as a pair of headphones, may then be plugged into the adapter jack 1814 while the handheld device 1802 in enclosed in protective enclosure 1800 . Alternatively, a one-piece adapter that includes both a jack 1814 and a plug 1812 without a cable 1816 may be integrally disposed into shell base 1804 . Shell lid 1806 is adapted to retain an O-ring 1808 that seals the protective enclosure 1800 when shell lid 1806 is latched tightly onto shell base 1804 so that water cannot enter protective enclosure 1800 . FIG. 19 illustrates in the open position a crush-resistant, impact-resistant, watertight, protective enclosure 2000 for an electronic device such as a laptop computer. The protective enclosure 2000 may be manufactured in a manner similar to the enclosure of FIG. 13 comprising an impact/crush resistant material such as glass-fiber reinforced engineered thermoplastic, such as for example, glass reinforced polycarbonate. It may also be made of thermoplastic polycarbonate, thermoplastic polypropylene, thermoplastic acrylonitrile-butadiene-styrene, and thermoplastic compositions containing one or more thereof, or other engineered thermoplastics that provide a shock-resistant and impact resistant shell. The inside of the enclosure is covered with a hook and loop liner 2002 . Shock absorbing corner bumpers 2004 have hook and loop type bases so that they may attach at any point on the liner inside the enclosure at the corners of the electronic device to secure electronic devices of various sizes and provides a shock absorbent suspension system for the devices. The shape of the bumpers may vary in size and in depth. They may also vary such that the laptop is raised a predetermined height for the bottom of the enclosure so that there may be access to the ports and external drives such as CD and DVD. These bumpers allow the enclosure to be adaptable to any size laptop computer by placing it inside the enclosure and securing it into position with the bumpers 2004 . Straps 2006 also secures the laptop into position. FIG. 20 illustrates a laptop 2008 secured in position as described above. An opening for a door or docking position 2010 may be provided that allows the case to be prewired for power or other USB connections. The watertight access ports may include holes that have a moveable watertight plug, or any type of watertight button or lever. The liner 2002 may also have some cushioning that cushions the laptop and protects it against breakage if the enclosure and laptop are dropped or otherwise subjected to shock. Normally, however, most of the cushioning is provided by the corner bumpers and the liner is not cushioned. In accordance with the embodiment of FIG. 19 , the liner 2002 has a thickness of approximately 0.25. This enclosure is also adaptable to protect PC tablets of the type illustrated in FIG. 13A . The hook and loop liner may be adjacent to the touch screen but does not exert mechanical pressure on the touch screen so that mechanical inputs such as style stokes are sensed only when intended. The engineered thermoplastics may be reinforced with glass fibers, carbon fibers, metal fibers, polyamide fibers, and mixtures thereof. Referring to FIG. 21 the enclosure 2000 may have an elevated protective rim 2012 substantially surrounding a perimeter of the enclosure. This rim may be further reinforced with stiffeners made of steel or other hard material that are integrally embedded into the enclosure so that the stiffeners provide additional strength and protection to the enclosed devices, as shown in FIG. 13B . An adjustable heavy-duty handle 2016 may be attached to or integrally designed into protective enclosure 2000 to allow easy and reliable transportation. FIG. 22 illustrates the top of the enclosure wherein heavy-duty corner bumpers, such as bumper 2016 , provide additional protection against mechanical shock and are securely attached to the corners of the base. The ribs 2012 also substantially surround a perimeter of the base of the enclosure. FIG. 23 illustrates a front view of the protective enclosure 2000 . An addition protective rib 2018 is provided along the front of the case and extends around the case on the ends, as shown in FIG. 24 . FIG. 25 illustrates the back of the protective enclosure wherein an opening 2010 is provided in the protective enclosure 2000 which is sealed with a rubber plug 2020 . The plug 2020 of the USB hub is shown in more detail in FIG. 26 . The USB cable hub allows the protective enclosure 2000 to be wired for both power as well as USB connections. In addition, provisions may be made to provide ventilation for the enclosure through opening 2010 . FIG. 26 illustrates the USB hub 2021 . The hub has mounting apertures such as 2022 that are disposed to receive fasteners to mount the hub inside of the protective enclosure 2000 . A USB connector 2024 , that is disposed to connect to a USB slot in a computer laptop or PC tablet computer, is connected by a cable 2026 to the hub 2020 . FIG. 27 illustrates the integrated USB hub 2021 mounted in the enclosure 2000 . The cable 2026 and USB connector 2024 allow a laptop computer or other computer to be connected to the USB hub 2021 . The corner bumpers 2004 are disposed to be removably attached to the enclosure lining 2002 so that the computer may be moved to a new location or the inside of the protective enclosure 2000 to facilitate the making of a connection between a laptop computer and the hub 2020 . The hook and loop liner 2005 , that is attached to the base of the shock absorbing corner bumpers 2004 , extends beyond the base dimensions by a predetermined amount to increase the adhesion between the bumpers 2004 and liner 2002 of the enclosure 2000 . FIG. 28 illustrates how the USB assembly comprising the hub 2021 , cable 2026 , and connector 2026 may be mounted in an enclosure for a PC tablet protective enclosure such as 1400 shown in FIG. 14 . The foregoing description of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and other modifications and variations may be possible in light of the above teachings. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments of the invention except insofar as limited by the prior art.
A protective cover for an electronic device that has an interactive control panel and one or more electrical contacts includes a protective shell having a first member and a second member. The first member has a first coil arranged to convey electromagnetic energy with respect to a second, external coil. The second member is configured to join with the first case member to at least partially cover the electronic device. An aperture defined by the protective shell is aligned with the interactive control panel when the electronic device is at least partially enclosed by the protective shell. An electrical connection attached to the protective shell is configured to directly or indirectly convey electrical power received at the first coil to at least one of the electrical contacts of the electronic device to provide an electrical connection to the electrical source when the electronic device is received by the first member.
Summarize the key points of the given document.
[ "CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser.", "No. 14/031,700 entitled “Protective Enclosure for Electronic Device,” filed Sep. 19, 2013, which is a continuation of U.S. patent application Ser.", "No. 12/560,621 entitled “Protective Enclosure for Electronic Device,” filed Sep. 16, 2009, which is a division of U.S. patent application Ser.", "No. 11/456,157 entitled “Protective Enclosure for Electronic Device,” filed Jul. 7, 2006 (now U.S. Pat. No. 7,609,512), which is a continuation-in-part of U.S. patent application Ser.", "No. 10/937,048 entitled “Protective Enclosure for an Interactive Flat-Panel Controlled Device,” filed Sep. 8, 2004 (now U.S. Pat. No. 7,158,376), which is a continuation-in-part of U.S. patent application Ser.", "No. 10/645,439 entitled “Protective Membrane for Touch Screen Device,” filed Aug. 20, 2003 (now U.S. Pat. No. 6,995,976), which is a continuation of U.S. patent application Ser.", "No. 10/300,200 entitled “Protective Case for Touch Screen Device,” filed Nov. 19, 2002 (now U.S. Pat. No. 6,646,864), which claims the benefit of and priority to U.S. Provisional Patent Application Ser.", "No. 60/335,865 filed Nov. 19, 2001 entitled “Protective Case for Touch Screen Device.”", "The entire contents of the above mentioned applications and patents are hereby specifically incorporated by reference in their entirety.", "BACKGROUND OF THE INVENTION Portable electronic devices (PEDs), such as PDAs, computers, MP3 players, music players, video players, smart phones, GPS receivers, telematics devices, cell phones, satellite phones, pagers, monitors, etc.", ", are being very widely used, and are being deployed in industrial as well as office environments.", "PEDs are being used in industrial environments for data collection, such as service information on an airplane, or for data delivery such as maps for fire fighters and other emergency personnel.", "When PEDs are deployed in such industrial applications, the data that is collected and displayed on the PED can be extremely valuable and can be lifesaving.", "The industrial environments impose harsh conditions that typical PEDs are not designed to accommodate.", "For example, damage can be done to the PED through rough handling and dropping.", "Further, industrial chemicals, grease, water, dirt, and grime may damage or destroy a functioning PED and inhibit the use of the PEDs valuable data.", "It is common to hold the PEDs inside a protective case for transport.", "However, PEDs are usually removed for use since most cases used for transport are not interactive.", "Interactive cases are also useful for non-industrial applications to provide protection for PEDs.", "SUMMARY OF THE INVENTION A protective enclosure for an electronic device is provided.", "The protective enclosure includes a first case member, a second case member, a rigid plunger, and an electrical conductor.", "The second case member is hingeably attached to the first case member to form a shell that includes a watertight enclosure for the electronic device.", "The rigid plunger is adapted to transmit a mechanical motion from outside the shell to the electronic device inside the shell.", "The electrical conductor includes an electrical plug to mate to an electrical jack of the electronic device in the watertight enclosure to electrically connect the electronic device to a device outside the shell.", "BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, FIG. 1 is a perspective view of an embodiment of the invention shown in the closed position.", "FIG. 2 is a perspective view of an embodiment of the invention shown in the open position.", "FIG. 3 is a perspective view of an embodiment of the invention shown in an exploded state.", "FIG. 4 is a perspective view of an embodiment of the invention shown from the rear.", "FIG. 5 is a front view of an embodiment of the invention, showing a section line.", "FIG. 6 is a section view of an embodiment of the invention.", "FIG. 7 is a detailed view of a section shown in FIG. 6 .", "FIG. 8 is a perspective view of another embodiment comprising a single piece encapsulating cover.", "FIG. 9 is a perspective view of a third embodiment comprising a non-encapsulating snap over cover.", "FIG. 10 is a perspective view of an embodiment that comprises a belt clip.", "FIG. 11 is a second perspective view of an embodiment that comprises a belt clip.", "FIG. 12 is a perspective view of another embodiment of the present invention of a protective cover for a PED or other device.", "FIG. 13A is a perspective top view of another embodiment of a protective enclosure for a tablet PC.", "FIG. 13B is a view of the protective enclosure lid of FIG. 13A .", "FIG. 14 is a perspective top view of the embodiment of FIG. 13A with an open lid.", "FIG. 15 is a perspective bottom view of the embodiment of FIG. 13A .", "FIG. 16 is a perspective view of the base of the embodiment of FIG. 13A FIG. 17 is an exploded view of an embodiment of a protective enclosure for an interactive flat-panel controlled device.", "FIG. 18 is an exploded view of another embodiment of a protective enclosure for an interactive flat-panel controlled device.", "FIG. 19 is an exploded view of another embodiment of a protective enclosure with an open lid for a laptop computer device.", "FIG. 20 is an exploded view of a protective enclosure with an open lid for a laptop computer device positioned inside the enclosure.", "FIG. 21 is a perspective top view of a protective enclosure with a closed lid for a laptop computer device.", "FIG. 22 is a perspective bottom view of the protective enclosure FIG. 21 .", "FIG. 23 is a perspective front view of the embodiment of FIG. 21 .", "FIG. 24 is a perspective end view of the embodiment of FIG. 21 .", "FIG. 25 is a perspective back view of the embodiment of FIG. 21 .", "FIG. 26 is a perspective view of the USB hub.", "FIG. 27 is a perspective view of the USB hub mounted inside the enclosure of FIG. 21 .", "FIG. 28 is a perspective view of the USB hub mounted inside the enclosure of FIG. 14 .", "DETAILED DESCRIPTION FIG. 1 is a perspective view of an embodiment of the invention.", "Embodiment 100 comprises a rigidly molded front case 102 and rear case 104 .", "An overmolded grommet 106 forms a receptacle for stylus 108 and also aids in sealing membrane 110 .", "A flexible hand strap 112 attaches to the rear case 104 .", "A hinge 114 joins front case 102 and rear case 104 .", "A ring 124 for a lanyard is shown as an integral feature of rear case 104 .", "Embodiment 100 is designed to hold a conventional personal digital assistant (PED) in a protective case.", "A PED, such as a Palm Pilot, Handspring Visor, Compaq Ipaq, Hewlett Packard Jornada, or similar products, use a touch screen for display and data entry.", "The touch screen display comprises either a color or black and white liquid crystal display with a touch sensitive device mounted on top of the display.", "The display is used for displaying graphics, text, and other elements to the user.", "The touch screen is used with a stylus 108 to select elements from the screen, to draw figures, and to enter text with a character recognition program in the PED.", "The stylus 108 generally resembles a conventional writing implement.", "However, the tip of the writing implement is a rounded plastic tip.", "In place of a stylus 108 , the user may use the tip of a finger or fingernail, or a conventional pen or pencil.", "When a conventional writing implement is used, damage to the touch screen element may occur, such as scratches.", "For the purposes of this specification, the term PED shall include any electronic device that has a touch screen interface.", "This may include instruments such as voltmeters, oscilloscopes, logic analyzers, and any other hand held, bench top, or rack mounted instrument that has a touch screen interface.", "Hand held devices, such as cell phones, satellite phones, telemetric devices, and other hand held devices are also to be classified as PEDs for the purposes of this specification.", "The term PED shall also include any computer terminal display that has a touch screen interface.", "These may comprise kiosks, outdoor terminal interfaces, industrial computer interfaces, commercial computer interfaces, and other computer displays.", "Additionally, the term PED may comprise barcode scanners, hand held GPS receivers, and other handheld electronic devices.", "The foregoing description of the term PED has been presented for purposes of illustration and description.", "It is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and other modifications and variations may be possible in light of the teachings of this specification.", "In addition, the PEDs typically have a handful of additional buttons as part of the user interface.", "These buttons are generally on the front of the device, near the touch screen element.", "The additional buttons may be used as shortcut buttons to instantly call up a certain program on the PED, may comprise a method of scrolling, may be used to select items from a list, or may have any function that the designer of the PED software may assign to the button or set of buttons.", "The button size, layout, and function may vary for each manufacturer and model of PED.", "Further, PEDs typically have at least one method of connecting to another computer.", "This may be through a direct electrical connection, such as through a wire cable or fiber optic, or through another medium such as infrared communication or through a radio communication.", "Additionally, the PEDs typically have an electrical source.", "The electrical source may be a rechargeable or non-rechargeable battery or solar cells.", "The electrical source may be a remote source of electricity that is transmitted to the PED through a wire cable or through other methods of electrical transmission.", "Further, PEDs may have indicator lights, such as status lights for power, communication, battery status, or other functions.", "The lights may be located on any of the sides of the PED and may be viewable on one or more sides.", "Front case 102 and rear case 104 form a protective cover for the PED.", "The protective cover may be designed for rugged industrial use, recreational use, commercial use, or many other uses.", "An industrial use may require the protective cover to be watertight, chemically resistant, protect the unit when dropped, and be crush proof.", "A typical application may be for fire fighters to use a PED for a display of maps for directions to an emergency scene or for a building plan at the scene of a fire.", "Another example may be a maintenance mechanic in a chemical plant using a PED to record maintenance records in the plant that processes.", "A recreational use may require the cover to be watertight, afford some protection against dropping and being crushed, float in water, and be dust resistant.", "A recreational use may be to take the PED during kayaking, diving, or other water sport activity.", "Further, the case may be used when the PED is taken camping, hiking, or other outdoor activity.", "A commercial use may additionally require the protective cover to be elegant, but may also require the cover to be replaceable so that scratches and other signs of wear and tear can be easily and cheaply replaced.", "The protective cover for the PED may take on many embodiments.", "The embodiment 100 comprises a front case 102 and rear case 104 that are joined by a hinge 114 and a clasp mechanism that is on the side of the cases opposite the hinge 114 .", "Other embodiments may have a small door into which the PED slides, or the protective cover may not completely enclose the PED and only cover the face where the user interface exists, leaving one or more sides of the PED exposed.", "Those skilled in the art may use other designs of protective covers without deviating from the scope and intent of the present invention.", "The protective cover may be constructed of rigid plastic, metal, flexible rubber, or any other type of material that could be adapted to afford the protection of the PED desired for the application.", "For example, a metal cover may be used in an application where an elegant style is necessary but watertightness is not.", "A flexible rubber cover may be selected for an application in a wet environment.", "A rigid plastic cover may be selected for an application where dropping the PED is a concern.", "Those skilled in the art may use other types of materials and constructions without deviating from the spirit of the present invention.", "The PED may be mounted in the protective cover using many different mounting techniques.", "For example, the PED may be mounted using open or closed cell foam inserts in the protective cover.", "In another embodiment, the PED may be mounted by attaching the PED to the cover with a fastener.", "In another embodiment, the PED may be mounted by snapping into the protective waterproof cover.", "In another embodiment, the PED may be held in place by resting in molded features of two halves of a protective case that clamps onto the PED.", "Those skilled in the art may use other types of locating and holding mechanisms without deviating from the spirit of the present invention.", "The overmolded grommet 106 of the present embodiment is constructed by injection molding a thermoplastic polymerized rubber (TPR) over the front case 102 .", "The grommet 106 has molded features 116 and 118 adapted to retain the stylus 108 .", "Features 116 and 118 capture the stylus 108 during transportation, but allow the user to remove the stylus 108 to operate the PED.", "In other embodiments of the present invention, the stylus 108 may be constrained to the PED with a tether or lanyard, or the constraining features may be incorporated into other components that make up the protective cover.", "Further, the stylus 108 may not be present in the embodiment, rather, the PED be adapted to be used with the user's fingernail or with another implement similar to the stylus 108 .", "The membrane 110 of the present embodiment is constructed by thermoforming a sheet of thin plastic.", "The plastic is selected to be thin enough that the deformation of a stylus conducts the touch to the touch screen, but thick enough to have enough rigidity that the stylus does not catch and rip the membrane.", "Additionally, the membrane 110 should have enough thickness to endure scratches and other wear and tear without breaking and sacrificing the protective function.", "Polyvinylchloride material at 0.010 inches to 0.015 inches thickness gives acceptable results.", "Alternatively, membrane 110 may be constructed by injection molding or other methods.", "Alternative materials may be used by those skilled in the art to achieve the same results while maintaining within the spirit and intent of the present invention.", "The membrane 110 in the present embodiment may be translucent or at least partially transparent, so that the images displayed on the PED may be visible through the membrane 110 .", "The membrane 110 may be tinted or colorized in some applications.", "For example, a protective cover designed as a decorative cover may incorporate a colorized membrane 110 .", "Further, the membrane may be selectively colorized and the opaqueness may vary.", "For example, the protective membrane may be printed or painted in the areas not used for the touch screen.", "A printing process may incorporate a logo, graphics, or labeling for individual buttons for the PED.", "The printing process may further incorporate features, such as text or graphics, that are used by the software on the PED for a purpose such as simplifying data input or for designating an area on the touch screen for a specific function, such as a help function.", "The printing or painting processes used on the membrane 110 may be purely decorative and may be for aesthetic purposes only.", "The printing process may also comprise logos or graphics for the brand identity of the PED cover.", "Other processes, such as colorizing the raw material for the membrane 110 or adding other components to the raw material, such as metal flakes or other additives, may be used to change the optical features of the membrane 110 .", "The optical performance of the membrane 110 may be changed or enhanced by changing the texture of the area of the touch screen.", "For example, the membrane may be frosted on the outside to hide scratches or may be imprinted with a lens or other features that change the optical characteristics of the membrane 110 .", "The membrane 110 may have optical features that are used in conjunction with the software of the PED.", "For example, all or a portion of the membrane may comprise a lens that magnifies an image to a user.", "When the user touches the image on the membrane 110 and the touch is transferred to the touch screen, the software in the PED may have to compensate for the positional differences between the image and actual area that was touched by the user.", "In another example, if a specific portion of the membrane 110 had a specific optical characteristic, the software of the PED may be constructed to display a specific graphic for the area for an intended effect.", "The membrane 110 in the present embodiment has a recessed portion 120 and a raised portion 122 .", "The recessed portion 120 may be adapted to press flat against the touch screen area of a specific PED.", "The raised portion 122 may be adapted to fit over an area of the specific PED where several buttons are located.", "The raised portion 122 allows the user to operate the buttons on the PED.", "The raised portion 122 is adapted such that the buttons on the PED are easily operated through the protective membrane 110 .", "The raised portion 122 may have special features to aid the user in pressing the buttons.", "For example, the raised portion 122 may comprise a dimpled area for the user's finger located directly over the button.", "Further, a feature to aid the user may comprise a section of membrane 110 defined by a thinner area around the section, enabling the user to more easily deflect the section of membrane over the button.", "The area of thinner material may comprise a large section or a thin line.", "Further, tactile elements, such as small ribs or bumps may be incorporated into the membrane 110 in the area of the buttons so that the user has a tactile sensation that the user's finger is over the button.", "The tactile element may be particularly effective if the button was a power switch, for example, that turned on the PED.", "The configuration of the membrane 110 may be unique to each style or model of PED, however, the front case 102 and rear case 104 may be used over a variety of PEDs.", "In the present embodiment, the changeover from one PED variety to another is accomplished by replacing the membrane 110 without having to change any other parts.", "The present embodiment may therefore be mass-produced with the only customizable area being the membrane 110 to allow different models of PEDs to be used with a certain front case 102 and rear case 104 .", "The hand strap 112 in the present embodiment allows the user to hold the embodiment 100 securely in his hand while using the PED.", "The hand strap 112 may be constructed of a flexible material, such as rubber or cloth webbing, and may have an adjustment, such as a buckle, hook and loop fastener, or other method of adjustment.", "In other embodiments, a hand strap may be a rigid plastic handle, a folding handle, or any other method of assisting the user in holding the embodiment.", "Further, the embodiment may be adapted to be fix-mounted to another object, like a piece of machinery, a wall, or any other object.", "A fix-mounted embodiment may have other accoutrements adapted for fixed mount applications, such as receptacles for a stylus adapted to a fix-mount, specialized electrical connections, features for locking the PED inside the case to prevent theft, or designs specifically adapted to shed water when rained upon.", "FIG. 2 illustrates a perspective view of the embodiment 100 shown in an open position.", "The front case 102 and rear case 104 are shown open about the hinge 114 .", "Membrane 110 is shown installed into gasket 106 , and the recessed portion 120 and raised portion 122 of membrane 110 is illustrated looking from the inside of the case.", "The clasp mechanisms are not shown in this illustration.", "Hand strap 112 is shown attached to rear case 104 .", "FIG. 3 illustrates a perspective view of the embodiment 100 shown in an exploded state.", "The hand strap 116 attaches to the rear cover 104 .", "The overmolded grommet 106 holds the stylus 108 and is attached to front cover 102 .", "The membrane 110 attaches to the grommet 106 and is held in place with an o-ring 302 .", "FIG. 4 illustrates a perspective view of the embodiment 100 shown from the rear.", "The hand strap 116 is shown, along with rear cover 104 and front cover 102 .", "The stylus 108 is shown inserted into the overmolded grommet 106 .", "FIG. 5 illustrates a top view of the embodiment 100 .", "The front cover 102 , membrane 110 , stylus 108 , and hinge 114 are all visible.", "FIG. 6 illustrates a section view of the embodiment 100 taken through the section line shown in FIG. 5 .", "The front cover 102 , rear cover 104 , overmolded gasket 106 , stylus 108 , membrane 110 , hand strap 112 , and o-ring 302 are all shown hatched in this view.", "FIG. 7 illustrates a detail view of the embodiment 100 shown in FIG. 6 .", "Front case 102 and rear case 104 are joined at hinge 114 .", "Overmolded gasket 106 traps membrane 110 and o-ring 302 locks membrane 110 in place.", "Overmolded gasket 106 may be formed by molding thermoplastic polymerized rubber over the front cover 102 .", "The replacement of the membrane 110 is accomplished by removing o-ring 302 , pushing the membrane 110 from the overmolded gasket 106 , snapping a new membrane 110 into place, and replacing the o-ring 302 .", "The ease of replacement of the present embodiment allows a user to quickly replace a damaged membrane 110 , allows a user to upgrade their case to a newer model PED, and may allow a user to select from various membranes 110 for the particular application.", "One embodiment may have a single case packaged with a small variety of several types of membranes 110 .", "In such an embodiment, the user may purchase the packaged set, select the membrane 110 that suits the user's particular PED, and install the selected membrane 110 with ease.", "The protective cover of the present invention may have direct connections through the cover for connecting through the case.", "Such a connection is known as pass through.", "The connections may be for power, communication, heat dissipation, optical transmissions, mechanical motion, or other reasons.", "Electrical connections may require an insulated metal conductor from the PED through the wall of the protective cover so that a flexible cable may be attached or so that the PED in its protective case may be placed in a cradle for making the electrical connection.", "Inside the protective cover, the electrical connections may be made with a flexible cable that is plugged into the PEDs electrical connector before the PED is secured in the protective cover.", "Alternatively, a fixed connector may be attached to the protective cover and the PED is slid into contact with the fixed connector.", "Another embodiment may be for a compliant, yet fixed mounted electrical connector to be rigidly mounted inside the protective cover.", "A compliant, yet fixed mounted electrical connector 1830 may comprise spring loaded probes, commonly referred to as pogo pins.", "Another embodiment may comprise spring fingers that engage the PEDs electrical contacts.", "On the outside of the protective cover, the electrical contacts may be terminated into a fix-mounted connector adapted to receive a cable from a computer.", "The connector may be designed to receive a cable that plugs directly into the PED or it may be adapted to receive a different connector.", "Further, the electrical connection to the PED may be permanently attached to a cable that extends out of the protective cover.", "Another embodiment may be to have a small trap door that opens in the protective cover to allow access to the electrical connections.", "While the trap door exposes the PED to the elements the cover is designed to protect against, a direct electrical connection may eliminate a potential cabling connection problem.", "Connections for fiber optics can be handled in similar fashions as the electrical connections.", "An embodiment with a power connection may comprise the use of inductive coils, such as inductive coil 1840 , located in proximity to each other but on opposite sides of the protective cover.", "Those skilled in the art of may devise other embodiments for connecting through the protective cover without deviating from the scope and intent of the present invention.", "Through the air communications, such as infrared and over the air radio frequency (RF) communications may pass through the protective cover.", "The material for the front case 102 and rear case 104 may be selected to be clear plastic, such as polycarbonate.", "The infrared transceiver of the PED can communicate through a clear plastic case to another infrared transceiver outside of the case.", "Further, the appropriate selection of material for the protective case can thereby enable various RF transmissions, such as cellular phone communications or other wireless communication protocols.", "An infrared transmission through the protective case of an embodiment of the invention may be accomplished by making the entire protective case out of a clear material.", "Alternatively, a selected area of the protective case may be clear while the remainder of the case is opaque.", "The selected area may be constructed of a separate piece that allows the infrared light through the protective case.", "Alternatively, the selected area may be constructed of a portion of the protective case that was manufactured in a way so as not to be opaque, such as selectively not painting or plating the area of a plastic protective case.", "Further, the clear material through which the transmission occurs may be tinted in the visual spectrum but be translucent or at least partially transparent in the infrared spectrum of the device.", "A protective case may allow RF transmissions to and from the PED while the case is closed.", "Such a case may be constructed of a non-metallic material.", "In some embodiments, the material of the protective case may be tuned to allow certain frequencies to pass through the protective cover and tune out other frequencies, through loading the material used in the protective cover with conductive media or through varying the thickness of the case and other geometries of the case in the area of the PED transmission and reception antenna.", "In a different embodiment, it may be desirable to shield the PED from outside RF interference.", "In this case, the protective cover may be a metallic construction or may be plastic with a metallized coating.", "Further, membrane 110 may have a light metallized coating applied so that membrane 110 is slightly or fully conductive.", "An application for such an embodiment may be the use of the PED in an area of high RF noise that may interfere with the operation of the PED, or conversely, the use may be in an area that is highly susceptible to external RF interference and the PEDs RF noise may be interfering with some other device.", "The PED may be equipped with a camera or other video capture device.", "A protective cover may have provisions to allow a clear image to be seen by the video capture device through the case.", "Such provisions may include an optically clear insert assembled into the protective case.", "Other embodiments may have a sliding trap door whereby the user of the PED may slide the door open for the camera to see.", "Additionally, other embodiments may comprise a molded case that has an optically clear lens integrally molded.", "Such an embodiment may be additionally painted, plated, or overmolded, with the lens area masked so that the painting, plating, or overmolding does not interfere with the optics of the lens.", "An optically clear area may be used for a barcode scanner portion of a PED to scan through the case to the outside world.", "In such an embodiment, a barcode scanner may be protected from the elements while still maintaining full functionality in the outside world.", "The PED may have indicator lights that indicate various items, such as power, battery condition, communication, and other status items.", "The indicator lights may be in positions on the PED that are not readily viewable through the protective membrane 110 .", "The indicator lights may be made visible through the protective case by using light pipes that transmit the light from the PEDs status light to the outside of the protective case.", "Such light pipes may be constructed of clear or tinted plastic, or other translucent or semi-transparent material.", "The light pipes may be formed as an integral feature to the protective case or may be separate parts that are formed separately and assembled to the protective case.", "The PED may have a speaker or other element that makes noise and/or the PED may have a microphone for receiving audio signals.", "The speaker may be an audio quality device for reproducing sound or it may be a simple buzzer for indicating various functions of the PED.", "The microphone may be an audio quality device or it may be a low performance device.", "Special provisions may be made for transmitting sound through a protective case.", "Such provisions may range from a single hole in the case to a tuned cavity that would allow sound to pass through with minimum distortion.", "Other embodiments may include a transmissive membrane adapted to allow sound to pass through the protective case with a minimum of distortion.", "Such membranes may be located near the speaker and microphone elements of the PED.", "Such membranes may be watertight membranes known by the brand name Gore-Tex.", "The PED may generate heat during its use and provisions for dissipating the heat may be built into the protective cover.", "A heat-dissipating device may be integral to the protective cover or may comprise one or more separate parts.", "For example, a metallic protective cover may be adapted to touch the PED in the area of heat generation and conduct the heat outwardly to the rest of the protective cover.", "The protective cover may thereby dissipate the heat to the external air without overheating the PED.", "In another example, a separate heat sink may be applied to the PED and allowed to protrude through a hole in the protective cover.", "The heat sink may thereby transfer the heat from the PED to the ambient environment without overheating the PED.", "The heat sinks may be attached to the PED with a thermally conductive adhesive.", "Other embodiments may include vent holes for heat dissipation and air circulation.", "The PED may have a button that may not be located underneath the membrane 110 .", "An embodiment may include a flexible, pliable, or otherwise movable mechanism that may transmit mechanical motion from the outside of the case to a button on the PED.", "Such an embodiment may have a molded dimpled surface that is pliable and allows a user to activate a button on a PED by pressing the dimpled surface.", "Another embodiment may have a rigid plunger that is mounted on a spring and adapted to transmit the mechanical movement from the exterior of the case to a button on the PED.", "The buttons on the PED may be located on any side of the PED and an embodiment of a case may have pliable areas adapted to allow the user to press buttons that are not on the front face of the PED.", "FIG. 8 is an illustration of embodiment 800 of the present invention wherein the PED 802 is encapsulated by a protective cover 804 .", "The installation of the PED 802 is to slide PED 802 into the opening 808 , then fold door 806 closed and secure with flap 810 , which is hinged along line 812 .", "Areas 814 and 816 may comprise a hook and loop fastener system or other fastening device.", "Recessed area 818 is adapted to fit against touch screen 820 of PED 802 .", "Embodiment 800 may be comprised of a single molded plastic part that may be very low cost.", "As shown, embodiment 800 may not be completely weathertight, since the door 806 does not completely seal the enclosure.", "However, such an embodiment may afford considerable protection to the PED 802 in the areas of dust protection, scratch protection, and being occasionally rained upon.", "Further, the low cost of the embodiment 800 may be changed often during the life of the PED 802 .", "Embodiment 800 may have custom colors, logos, or designs that allow a user to personalize their PED with a specific cover that is suited to their mood or tastes.", "The colors, logos, and designs may be integrally molded into the cover 804 .", "Alternatively, different colors, logos, and designs may be applied in a secondary operation such as printing, painting, plating, or other application process.", "FIG. 9 is an illustration of embodiment 900 of the present invention wherein a decorative cover 902 is snapped over a PED 904 .", "The ends 906 and 908 snap over the PED ends 910 and 912 as an attachment mechanism for cover 902 to PED 904 .", "Recessed area 914 is adapted to fit against touch screen 916 .", "Embodiment 900 may be a cover for decorative purposes only, or may be for protective purposes as well.", "Cover 902 may be emblazoned with logos, designs, or other visual embellishments to personalize the PED 904 .", "The colors, logos, and designs may be integrally molded into the cover 904 .", "Alternatively, different colors, logos, and designs may be applied in a secondary operation such as printing, painting, plating, or other application process.", "Embodiment 900 may be attached by snapping the cover 902 onto PED 904 .", "Special provisions in the case of PED 904 may be provided for a snapping feature of cover 902 , or cover 902 may be adapted to hold onto PED 904 without the use of special features in PED 904 .", "The features used to secure cover 902 to PED 904 may be any mechanism whereby the cover 902 can be secured.", "This includes snapping, clamping, fastening, sliding, gluing, adhering, or any other method for securing two components together.", "FIG. 10 illustrates a perspective view of an embodiment of a receiver 1002 for holding the protective case 100 .", "The protective case 100 is held into receiver 1002 in such a manner that the touch screen display is facing into the receiver 1002 , to afford the touch screen display with protection.", "FIG. 11 illustrates a perspective view of the embodiment of a receiver 1002 shown from the opposite side as FIG. 10 .", "Receiver 1002 is comprised of a back 1102 , a belt clip mechanism 1104 , and four clip areas 1106 , 1108 , 1110 , and 1112 .", "The protective case 100 is placed into the receiver 1002 by inserting one end into the receiver, then rotating the protective case 100 into position such that the snapping action of clip areas 1106 , 1108 , 1110 , and 1112 are engaged to hold protective case 100 securely.", "Receiver 1002 may be adapted to clip onto a person's belt or may be adapted to be mounted on a wall or other location where the PED may be stored.", "The orientation of the protective case 100 is such that the touch screen element of the PED is protected during normal transport and storage, since the touch screen interface is facing the back 1102 of the receiver 1002 .", "Receiver 1002 may be made of compliant plastic that allows the clip areas 1106 , 1108 , 1110 , and 1112 to move out of the way and spring back during insertion or removal of the protective case 100 .", "In the present embodiment, receiver 1002 may be constructed of a single part.", "In alternative embodiments, receiver 1002 may be constructed of multiple parts and of multiple materials, such as a metal back with spring loaded clips.", "In other embodiments, special features may be included in the protective case 100 where the receiver 1002 may engage a special feature for securing the protective case 100 .", "FIG. 12 illustrates an embodiment 1200 of the present invention of a protective cover for a PED or other device.", "A rigid front cover 1202 and a rigid rear cover 1204 are held together with a series of latches 1206 , 1208 , 1210 , and 1212 .", "The protective membrane 1214 protects the touchscreen of the enclosed PED.", "A folding rigid cover 1216 operates as a rigid shield to prevent the membrane 1214 from any damage.", "The stylus holder 1220 is formed from an overmolded flexible material in which the membrane 1214 is mounted.", "Embodiment 1200 illustrates yet another embodiment of the present invention wherein a rigid protective cover may be used to contain and protect an electronic device, but provide full usable access to a touchscreen.", "The protective membrane 1214 and case may be watertight in some embodiments.", "FIG. 13A illustrates an embodiment of a protective enclosure 1300 that encloses and protects a tablet PC 1302 .", "PEDs that have touch screens, as described above, have an interactive flat-panel control, i.e., the touch screen display.", "Tablet PCs are portable electronic computing devices that have a high-resolution interactive flat-panel control that accepts smooth stylus strokes such as handwriting.", "The embodiment of FIG. 13A is crush-resistant, impact-resistant, watertight, and simultaneously allows interactive stylus strokes and other sensitive user inputs to be accurately and easily transmitted through a protective screen membrane 1306 to the interactive flat-panel control of tablet PC 1302 .", "A watertight and shock-absorbing foam cushion 1310 may be fixed and sealed to the underside of the lid 1304 around the interactive flat-panel control opening.", "The protective screen membrane 1306 is fixed and sealed to the shock-absorbing foam cushion 1310 .", "The shock-absorbing foam cushion 1310 maintains the water tightness of the enclosure.", "The cushion 1310 also cushions the flat-panel control of the tablet PC 1302 and protects it against breakage if the enclosure and tablet PC are dropped or otherwise subjected to shock.", "In accordance with the embodiment of FIG. 13A , the shock-absorbing foam cushion 1310 has a thickness of approximately 0.25 inches and extends approximately 0.060 inches below the underside of the interactive flat-panel control opening of the lid 1304 .", "One source of suitable watertight shock-absorbing foam is E.A.R. Specialty Composites of 7911 Zionville Rd.", ", Indianapolis, Ind.", ", 46268.", "Cushion 1310 allows the protective screen membrane to move a distance of up to 0.125 inches during an impact to the enclosure or when pressure is applied to protect membrane 1306 while pushing the tablet PC control buttons 1308 or writing on the interactive flat-panel control with a stylus through the membrane.", "The shock-absorbing foam cushion 1310 also pushes the protective screen membrane 1306 flatly against the surface of the interactive flat-panel control of the tablet PC 1302 so that sensitive user stylus strokes and other inputs are accurately transmitted.", "The pressure of the cushion 1310 on the protective screen membrane 1306 which holds the protective screen membrane 1306 flatly against the interactive flat-panel control of the tablet PC 1302 also keeps display images, viewed through the protective screen membrane, clear and distortion-free.", "In embodiments of the protective enclosure to protect a touch-screen device, the protective membrane may be adjacent to the touch screen but does not exert mechanical pressure on the touch screen so that mechanical inputs such as style strokes are sensed only when intended.", "In embodiments of the protective enclosure to protect a tablet PC that has an RF stylus or to protect a handheld device that a capacitance-sensing interactive flat-panel control, the protective membrane may be pressed flat against the interactive flat-panel control which allows undistorted viewing but does not adversely affect the control since the interactive control uses capacitance or radio frequencies for interactive input instead of mechanical pressure.", "The protective screen membrane 1306 in the embodiment of FIG. 13A is at least partially transparent and has a thickness of approximately 0.010 inches.", "The thickness of the protective screen membrane 1306 should be typically in the range of 0.001 inches to 0.020 inches so that stylus strokes on the upper surface of protective screen membrane 1306 are transmitted accurately to the interactive flat-panel control of the tablet PC 1302 .", "Likewise, protective screen membrane 1306 may be flexible or semi-rigid and may be made of polyvinylchloride or other suitable transparent thermoplastic, such as, for example, polyvinylchloride, thermoplastic polycarbonate, thermoplastic polypropylene, thermoplastic acrylonitrile-butadiene-styrene, thermoplastic polyurethane, which has a hardness and texture that permits the stylus to smoothly glide across the surface without skipping, grabbing, or catching against the surface.", "Some tablet PCs utilize a stylus which transmits strokes to the PC by way of radio frequency transmission.", "Protective screen membrane 1306 may be made of a rigid, clear, engineered thermoplastic such as, for example, thermoplastic polycarbonate or other thermoplastics as described above, for enclosing a tablet PC.", "A protective screen membrane 1306 that is rigid may include watertight access ports that allow operation of mechanical buttons or switches of the tablet PC 1302 , such as, for example, control buttons 1308 .", "The watertight access ports may include holes that have a moveable watertight plug, or any type of watertight button or lever.", "Protective screen membrane 1306 may include an anti-glare coating or can be made with an anti-glare texture so that display images are clearly viewable without distortion through the protective screen membrane 1306 .", "In the embodiment of FIG. 13A , the lid 1304 of the protective enclosure 1300 may have an external stylus holder 1324 that securely holds a stylus used with the tablet PC 1302 .", "As described above with respect to FIG. 1 , the lid 1304 and the base 1312 may have air-permeable watertight vents 1318 , 1326 that permit the cooling fans of the tablet PC 1302 to force air exchange to dissipate heat by convection so that the tablet PC 1302 does not overheat.", "Watertight vents 1318 , 1326 may comprise holes in the lid 1304 and base 1312 that are made watertight by covering and sealing the holes with an air-permeable watertight membrane such as, for example, a fabricated expanded polytetrafluoroethylene (ePTFE) membrane.", "One source of expanded polytetrafluoroethylene (ePTFE) membranes is W.L. Gore &", "Associates, Inc. of 555 Papermill Road, Newark, Del.", ", 19711.", "The embodiment of FIG. 13A may also comprise a pod door 1322 that allows access to table PC interfaces such as, for example, PCMCIA or Smart Card slots.", "The pod door 1322 is attached to the lid 1304 so that it may be removed or opened.", "In the embodiment of FIG. 13A , the pod door 1322 is hingedly connected to a portion of the base 1312 at a location of the base 1312 that has an opening that allows access to the tablet PC interfaces.", "The opening can be covered by a watertight seal 1320 , such as, for example, an O-ring that is part of pod door 1322 .", "The underside of the lid 1304 also has a watertight seal, such as an O-ring, so that when compound latches 1328 , 1330 , 1332 , and 1334 are closed, the O-ring or seal of the lid 1304 forms a watertight seal against the base 1312 .", "The protective enclosure 1300 protects the tablet PC 1302 from water and dust intrusion sufficient to comply with Ingress Protection (IP) rating of IP 67 , i.e., the protective enclosure totally protects the enclosed tablet PC from dust and protects the enclosed tablet PC from the effects of immersion in one meter of water for 30 minutes.", "The protective enclosure of the embodiment of FIG. 13A may further comprise protective overmolding 1316 attached to the lid 1304 .", "A similar overmolding may be attached to the base 1312 .", "The protective overmolding 1316 may be made of material that is easily gripped in slippery conditions and provides additional shock absorption such as, for example, rubber or silicone.", "The protective overmolding 1316 extends above the surface of the lid in pre-determined areas to provide protrusions that are easily gripped even in slippery conditions.", "The protective enclosure of the embodiment of FIG. 13 may further comprise watertight plugs such as access port plug 1314 that fit snugly into openings in the base 1312 that provide access to various interfaces, connectors, and slots of the tablet PC 1302 .", "FIG. 13B illustrates a shell lid 1304 of the embodiment of FIG. 13A .", "Shell lid 1304 and base 1312 may be made of impact/crush resistant material such as glass-fiber reinforced engineered thermoplastic, such as for example, glass reinforced polycarbonate.", "Alternatively, the shell lid 1304 and shell base may be made of thermoplastic polycarbonate, thermoplastic polypropylene, thermoplastic acrylonitrile-butadiene-styrene, and thermoplastic compositions containing one or more thereof, or other engineered thermoplastics that provide a shock-resistant and impact resistant shell may be used.", "The engineered thermoplastics may be reinforced with glass fibers, carbon fibers, metal fibers, polyamide fibers, and mixtures thereof.", "Shell lid 1304 may be further reinforced with stiffeners 1334 , 1336 , 1338 , 1340 that are integrally embedded into the shell lid around the perimeter of an opening in the shell that is directly over the interactive flat-panel control portion of the tablet PC.", "The stiffeners may be made of steel or other hard material so that the stiffeners provide additional strength and prevent flexing of the lid 1304 which enhances the watertightness and the impact/crush resistance.", "FIG. 14 is an illustration of the embodiment of FIG. 13A with the lid 1404 detached from the base 1412 .", "To protect the tablet PC 1402 using the protective enclosure 1400 , the tablet PC 1402 is disposed to fit snugly into the base 1412 .", "The lid is oriented so that hooks 1436 , 1438 area aligned with pin 1440 that is connected to a portion of the base 1412 and the lid is closed so that hooks 1436 , 1438 are retained by pin 1440 .", "Compound latches 1428 , 1430 , 1432 , and 1434 are then snapped onto the lid so that the lid is compressed tightly against the base providing a watertight seal.", "FIG. 15 is a bottom view of the embodiment of FIG. 13 .", "The base 1516 of protective enclosure 1500 includes watertight vents such as watertight vent 1506 for air exchange to permit heat and sound dissipation from the enclosed tablet PC while at the same time maintaining watertightness.", "Pod release knobs 1512 , 1518 are attached to the base 1516 so that the knobs can be rotated clockwise to securely wedge against an edge of pod door 1522 to close the pod door 1522 tightly against a rim around the pod opening in base 1516 to create a watertight seal.", "Knobs 1512 , 1518 can be rotated counter-clockwise to release pod door 1522 to access the interfaces of the tablet PC covered by pod door 1522 .", "To provide additional protection against mechanical shock, heavy-duty corner bumpers such as bumper 1504 may be securely attached to the corners of base 1516 .", "As shown in FIG. 15 , an adjustable heavy-duty handle may be attached to the base 1516 of the protective enclosure 1500 to allow easy and reliable transportation of the protective enclosure 1500 that encloses a tablet PC.", "In some circumstances, it is convenient to hold the protective enclosure using hand strap 1514 that is made of strong slightly stretchable fabric.", "Hand strap 1514 attaches to four points of the base 1516 to that a user's hand or wrist can be inserted along the either the longer or shorted length on the protective enclosure 1500 and enclosure tablet PC.", "Hand strap 1514 may be made of neoprene or other strong stretchable material to securely hold the protective enclosure to the user's arm even in slippery conditions.", "The protective enclosure may further include a neck strap to provide a comfortable solution for using the tablet PC while standing.", "FIG. 16 illustrates a top view of the protective enclosure base 1600 .", "Watertight vents such as watertight vent 1616 allow air exchange for heat dissipation and sound transmission from an enclosed tablet PC.", "Seal rim 1614 is an integrally formed part of the protective enclosure 1600 which is compressed against an O-ring in the protective enclosure lid to provide a watertight seal when compound latches 1628 , 1630 , 1632 , and 1634 are closed onto the lid.", "Internal bumpers 1602 , 1604 , 1608 , 1610 attach to the interior corners of protective enclosure base 1600 to provide cushion and mechanical shock protection to an enclosed tablet PC.", "The L-shape and non-solid interior of internal bumpers 1602 , 1604 , 1608 , 1610 allows the bumpers to deflect and absorb the shock if the enclosed tablet PC is dropped or otherwise subjected to mechanical shock.", "The protective enclosure provides shock absorption sufficient to meet MIL-STD 810F, Method 516.5, Procedure 4, which is a Transit Drop Test.", "In the Transit Drop Test, the protective enclosure encloses a tablet PC or a mass equivalent to a tablet PC.", "The protective enclosure is sequentially dropped onto each face, edge, and corner for a total of 26 drops over plywood from a height of 48 inches.", "The protective enclosure is visually inspected after each drop and a functional check for leakage is performed after all drops are completed.", "Some tablet PCs have a docking connector disposed on the underside of the tablet PC so that the tablet PC can connect to power and signals.", "For example, emergency vehicles such as ambulances, fire trucks, or patrol cars, may have a docking station installed near the driver's seat onto which the driver may dock a tablet PC.", "The embodiment of protective enclosure base 1600 , as illustrated in FIG. 1 , may comprise a docking connector channel 1624 that is recessed with respect to the upper surface of the base that allows a docking connector to run from a docking connector that is disposed in the center underside of the tablet PC to access port 1626 .", "Alternatively, a docking pass-through connector 1620 may be made an integral and watertight part of the protective enclosure base 1600 so that the tablet PC docking connector attaches to the docking pass-through connector 1620 which, in turn, connects to the docking station in substantially the same manner as an unenclosed tablet PC.", "FIG. 17 illustrates another embodiment of protective enclosure 1700 for a handheld electronic device 1702 that has an interactive flat-panel control such as, but limited to, a capacitance-sensing interactive flat panel control, a touch screen or other interactive control.", "Handheld electronic devices that have an interactive flat-panel control benefit from being enclosed in a rugged protective enclosure that is crush-resistant, watertight, and shock-resistant and that simultaneously allows the user to interact with a sensitive interactive flat-panel control.", "Handheld electronic devices that have interactive flat-panel control may include music players, MP3 players, audio player/recorders, video players, computers, personal digital assistants (PDAs), GPS receivers, cell phones, satellite phones, pagers, monitors, etc.", "For example, Apple Computer Ipod is a popular handheld interactive device that plays MP3 or otherwise digitally-encoded music/audio.", "The Apple Ipod has an interactive flat-panel control in which a portion of the front panel is a flat-panel display and portion of the front panel is an interactive flat-panel control, called a touch wheel in some versions of the Ipod and click wheel in other versions of the Ipod, that has capacitive touch/proximity sensors.", "One function of such an interactive flat-panel control, i.e. touch wheel, is that the control can emulate a rotary control knob by sensing circular motion of a user's finger using capacitive sensors.", "The click wheel has the same function with the additional feature of sensing proximity of a user's finger and emulating button presses by a user's finger at pre-determined areas.", "In the embodiment of FIG. 17 , the shell lid 1706 and the shell base 1704 are made of polycarbonate or other engineered thermoplastics such as polyethylene, polypropylene, etc.", "that are crush-resistant and impact resistant.", "Shell base 1704 has a watertight seal 1718 , which may be an overmolded gasket, o-ring, liner or other seal that prevents water from entering the protective enclosure 1700 when the handheld interactive device 1702 is enclosed inside the protective enclosure 1700 .", "Shell base 1704 and shell lid 1706 may include watertight vents, electrical connectors, see-through areas or features as disclosed with respect to FIG. 1 .", "In the embodiment of FIG. 17 , shell lid 1706 includes apertures over predetermined portions of the handheld interactive device 1702 , such as the areas directly over the display screen 1714 and the interactive flat-panel control 1712 , or other designated areas, as desired.", "A protective screen membrane 1710 , that is at least partially transparent, is permanently or removably fixed in a watertight manner to the underside of shell lid 1706 in the aperture that is over the display screen 1714 .", "The protective screen membrane 1710 may be recessed with respect to the upper surface of the shell lid 1706 which provides protective elevated rim that protects the display screen 1714 from breakage.", "Protective screen membrane 1710 may be PVC, silicone, polyethylene or other material that is watertight and rugged.", "In the case that display screen 1714 is a touch screen, the protective screen membrane 1710 should be smooth enough and thin enough that stylus strokes and other inputs are transmitted accurately to the touch screen as disclosed above with respect to FIG. 1 , FIG. 12 , and FIG. 13 .", "Alternatively, it may be desirable not to have an aperture in shell lid 1706 for a protective membrane 1710 .", "In another embodiment, the shell lid 1706 can be made of a transparent material so that a transparent window can be formed in the shell lid 1706 in place of the protective screen membrane 1710 .", "The transparent window is aligned with the display screen 1714 so that the user can view the display screen 1714 .", "In this case, a protective elevated rim that is aligned with the display screen 1714 is not required in the shell lid 1706 to protect the display screen 1714 from damage since there is no protective screen membrane 1710 .", "If the display screen 1714 is a touch screen, the material of the shell lid 1706 that is aligned with the display screen 1714 to provide a window can be made thinner to allow the touch screen to properly operate.", "As also shown with respect to the embodiment of FIG. 17 , a protective control membrane 1708 is permanently or removably fixed in a watertight manner to the underside of shell lid 1706 in an aperture that is aligned with the interactive flat-panel control 1714 of the handheld device 1702 .", "The protective screen membrane 1710 is recessed with respect to the upper surface of the shell lid 1706 which provides protective elevated rim that protects the display screen 1714 from breakage and provides tactile feedback that guides a user's finger to the desired area, even in slippery conditions.", "Of course, the protective elevated rim may simply comprise the portion of the shell lid 1706 that is formed as a result of making an aperture in the shell lid 1706 and overmolding a protective touch-control membrane 1708 on an inside surface of the shell lid 1706 .", "In other words, the thickness of the shell lid 1706 creates a protective rim since the protective touch-control membrane 1708 is overmolded or otherwise attached to the back side of the shell lid 1706 .", "In that case, the rim is not elevated with respect to the surface of the shell lid 1706 , but rather, is elevated with respect to the membrane to form a protective rim.", "Interactive flat-panel control 1712 has capacitive sensors, which are part of a proximity/touch detector circuit.", "When a grounded object, such as a person's finger, which has free air capacitance of several hundred picofarads, is brought close to the capacitive sensors, the total capacitance measured by the detector circuit increases because the capacitance of the object with free air capacitance adds to the capacitance of the sensors since the total capacitance of two capacitors in parallel is additive.", "Multiple sensors may also be arranged so that movement of an object with free air capacitance can be detected, for example, movement of a person's finger in a circular motion analogous to turning a mechanical control knob.", "Some examples of interactive flat-panel controlled PEDs include Ipod and Ipod Mini music and audio players from Apple Computer.", "In some PEDs, such as the Apple Ipod, capacitive sensors may be disposed below a front panel made from a dielectric such as polycarbonate, which has a dielectric constant in the range of 2.2-3.8.", "In the embodiment of FIG. 17 , the protective control membrane 1708 is made of thin polycarbonate that is slightly flexible or other engineered thermoplastics that provide the rugged watertight protection and at the same time permit the capacitive sensors of the interactive flat-panel control 1712 to function correctly.", "Likewise, a protective control membrane 1708 with a dielectric constant that is too high may retain an electric charge long enough to reduce the response rate of the sensor to motion of a user's finger from one capacitive sensor zone of the interactive flat-panel control 1712 to another.", "A protective control membrane 1708 that is conductive or has a dielectric constant that is too low may diminish the sensitivity of the capacitive sensor by combining in series the capacitance of the protective membrane and the dielectric front panel of the PED which results in a lowering of the overall capacitance.", "Total capacitance between an object, such as a finger touching the protective control membrane 1708 , and interactive flat-panel control 1712 is a function of the thickness and the dielectric constant of the protective control membrane 1708 .", "The capacitance between the object, such as a finger, and the capacitive sensors of the interactive flat-panel control 1712 is proportional to the distance between the object and the sensors.", "The sensitivity of the capacitive sensors to the object may be diminished or completely eliminated if the protective control membrane 1708 is too thick.", "In the embodiment of FIG. 17 , the thickness of the protective control membrane is approximately 0.020 inches.", "The protective control membrane 1708 may be any thickness in the range of 0.003 inches to 0.020 inches that is adequate to provide a rugged watertight membrane through which capacitance can be correctly sensed by the interactive flat-panel control 1712 .", "The upper surface of the protective control membrane 1708 has a velvet/matte texture with a texture depth of 0.0004 to 0.003 inches that reduces the surface area of the membrane that is in frictional contact with the user's finger and permits a user's finger to glide rapidly upon the surface of the membrane without catching or sticking as a result of the reduced friction.", "The hardness of the polycarbonate material, or other hard engineered thermoplastic, also reduces the friction.", "Headphones or other accessories may be electrically connected to handheld device 1702 the through the protective enclosure 1700 by disposing the wire of the headphone or accessory in an insertable gasket 1716 which fits snugly into one end of the shell base 1704 .", "FIG. 18 illustrates another embodiment of protective enclosure 1800 which is substantially the same as protective enclosure 1700 of FIG. 17 .", "However, protective enclosure 1800 has an alternative electrical pass-through for accessories.", "In the embodiment of FIG. 18 , shell base 1804 includes an adapter cable 1816 that has an adapter plug 1812 at one end which plugs into a jack of handheld device 1802 .", "At the other end of the adapter cable 1816 is an adapter jack 1814 that is molded into, or otherwise integrally made part of, shell base 1804 .", "An external accessory, such as a pair of headphones, may then be plugged into the adapter jack 1814 while the handheld device 1802 in enclosed in protective enclosure 1800 .", "Alternatively, a one-piece adapter that includes both a jack 1814 and a plug 1812 without a cable 1816 may be integrally disposed into shell base 1804 .", "Shell lid 1806 is adapted to retain an O-ring 1808 that seals the protective enclosure 1800 when shell lid 1806 is latched tightly onto shell base 1804 so that water cannot enter protective enclosure 1800 .", "FIG. 19 illustrates in the open position a crush-resistant, impact-resistant, watertight, protective enclosure 2000 for an electronic device such as a laptop computer.", "The protective enclosure 2000 may be manufactured in a manner similar to the enclosure of FIG. 13 comprising an impact/crush resistant material such as glass-fiber reinforced engineered thermoplastic, such as for example, glass reinforced polycarbonate.", "It may also be made of thermoplastic polycarbonate, thermoplastic polypropylene, thermoplastic acrylonitrile-butadiene-styrene, and thermoplastic compositions containing one or more thereof, or other engineered thermoplastics that provide a shock-resistant and impact resistant shell.", "The inside of the enclosure is covered with a hook and loop liner 2002 .", "Shock absorbing corner bumpers 2004 have hook and loop type bases so that they may attach at any point on the liner inside the enclosure at the corners of the electronic device to secure electronic devices of various sizes and provides a shock absorbent suspension system for the devices.", "The shape of the bumpers may vary in size and in depth.", "They may also vary such that the laptop is raised a predetermined height for the bottom of the enclosure so that there may be access to the ports and external drives such as CD and DVD.", "These bumpers allow the enclosure to be adaptable to any size laptop computer by placing it inside the enclosure and securing it into position with the bumpers 2004 .", "Straps 2006 also secures the laptop into position.", "FIG. 20 illustrates a laptop 2008 secured in position as described above.", "An opening for a door or docking position 2010 may be provided that allows the case to be prewired for power or other USB connections.", "The watertight access ports may include holes that have a moveable watertight plug, or any type of watertight button or lever.", "The liner 2002 may also have some cushioning that cushions the laptop and protects it against breakage if the enclosure and laptop are dropped or otherwise subjected to shock.", "Normally, however, most of the cushioning is provided by the corner bumpers and the liner is not cushioned.", "In accordance with the embodiment of FIG. 19 , the liner 2002 has a thickness of approximately 0.25.", "This enclosure is also adaptable to protect PC tablets of the type illustrated in FIG. 13A .", "The hook and loop liner may be adjacent to the touch screen but does not exert mechanical pressure on the touch screen so that mechanical inputs such as style stokes are sensed only when intended.", "The engineered thermoplastics may be reinforced with glass fibers, carbon fibers, metal fibers, polyamide fibers, and mixtures thereof.", "Referring to FIG. 21 the enclosure 2000 may have an elevated protective rim 2012 substantially surrounding a perimeter of the enclosure.", "This rim may be further reinforced with stiffeners made of steel or other hard material that are integrally embedded into the enclosure so that the stiffeners provide additional strength and protection to the enclosed devices, as shown in FIG. 13B .", "An adjustable heavy-duty handle 2016 may be attached to or integrally designed into protective enclosure 2000 to allow easy and reliable transportation.", "FIG. 22 illustrates the top of the enclosure wherein heavy-duty corner bumpers, such as bumper 2016 , provide additional protection against mechanical shock and are securely attached to the corners of the base.", "The ribs 2012 also substantially surround a perimeter of the base of the enclosure.", "FIG. 23 illustrates a front view of the protective enclosure 2000 .", "An addition protective rib 2018 is provided along the front of the case and extends around the case on the ends, as shown in FIG. 24 .", "FIG. 25 illustrates the back of the protective enclosure wherein an opening 2010 is provided in the protective enclosure 2000 which is sealed with a rubber plug 2020 .", "The plug 2020 of the USB hub is shown in more detail in FIG. 26 .", "The USB cable hub allows the protective enclosure 2000 to be wired for both power as well as USB connections.", "In addition, provisions may be made to provide ventilation for the enclosure through opening 2010 .", "FIG. 26 illustrates the USB hub 2021 .", "The hub has mounting apertures such as 2022 that are disposed to receive fasteners to mount the hub inside of the protective enclosure 2000 .", "A USB connector 2024 , that is disposed to connect to a USB slot in a computer laptop or PC tablet computer, is connected by a cable 2026 to the hub 2020 .", "FIG. 27 illustrates the integrated USB hub 2021 mounted in the enclosure 2000 .", "The cable 2026 and USB connector 2024 allow a laptop computer or other computer to be connected to the USB hub 2021 .", "The corner bumpers 2004 are disposed to be removably attached to the enclosure lining 2002 so that the computer may be moved to a new location or the inside of the protective enclosure 2000 to facilitate the making of a connection between a laptop computer and the hub 2020 .", "The hook and loop liner 2005 , that is attached to the base of the shock absorbing corner bumpers 2004 , extends beyond the base dimensions by a predetermined amount to increase the adhesion between the bumpers 2004 and liner 2002 of the enclosure 2000 .", "FIG. 28 illustrates how the USB assembly comprising the hub 2021 , cable 2026 , and connector 2026 may be mounted in an enclosure for a PC tablet protective enclosure such as 1400 shown in FIG. 14 .", "The foregoing description of the invention has been presented for purposes of illustration and description.", "It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and other modifications and variations may be possible in light of the above teachings.", "The embodiment was chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated.", "It is intended that the appended claims be construed to include other alternative embodiments of the invention except insofar as limited by the prior art." ]
This appln is a cont of Ser. No. 09/388,445 filed Sep. 2, 1999, abn. FIELD OF THE INVENTION This invention relates to a nematic liquid crystal composition. More particularly, the invention relates to a liquid crystal composition suitable for an active-matrix (AM) mode and to a liquid crystal display device using the liquid crystal composition. BACKGROUND OF THE INVENTION The liquid crystal display device of the active-matrix mode (AM-LCD) is the center of attention as the favorite of LCD, since it permits a high-definition display. It has been applied for a display screen of laptop computers, digital still camera, digital video camera and the like. The AM-LCD liquid crystal compositions have required the following characteristics (1) to (5). (1) The liquid crystal composition should exhibit a nematic phase in as wide a temperature range as possible in order to extend an environmental temperature at which the liquid crystal display device is used. (The upper-limit temperature of the nematic phase is increased as high as possible and the lower-limit temperature of the nematic phase is reduced as low as possible.) (2) A viscosity of the liquid crystal composition should be reduced as low as possible in order to decrease a response time of the liquid crystal display device. (3) An optical anisotropy (Δn) of the liquid crystal composition can take a suitable value depending on a cell thickness (d) of the liquid crystal display device in order to increase a contrast of the liquid crystal display device. (4) A specific resistance of the liquid crystal composition should be increased and a voltage holding ratio of a cell in which the liquid crystal composition is contained should be increased in order to increase a contrast of the liquid crystal display device. In particular, a voltage holding ratio at high temperatures should be increased. The measurement of the voltage holding ratio at high temperatures is equivalent to an accelerated test to make sure of the durability of the liquid crystal composition. (5) A threshold voltage of the liquid crystal composition should be reduced in order to provide a smaller-sized battery serving as a power for driving the liquid crystal display device. In view of such background, Japanese Patent Kokai 8-73857 discloses the liquid crystal compositions having high voltage holding ratios, low threshold voltage and moderately large optical anisotropy. Japanese Patent Kokai 9-31460 also discloses the liquid crystal compositions particularly having low threshold voltage, good compatibility at low temperatures and a wide temperature range of a nematic phase. As liquid crystal compounds for low-voltage driving in various modes including AM and STN modes, WO 96/11897 discloses new liquid crystalline compounds having large dielectric anisotropy and very low viscosity as well as liquid crystal compositions containing said compounds. The liquid crystalline compounds having large dielectric anisotropy are required to use in order to reduce the threshold voltage of the liquid crystal composition. In general, the use of the liquid crystalline compounds having large dielectric anisotropy for the preparation of the liquid crystal composition increases the viscosity of the liquid crystal composition. A response time is proportional to the square of a cell gap, as proposed by E. Jakeman et al., Phys. Lett., 39A (1972) 69. Accordingly, the liquid crystal display device using the liquid crystal composition having reduced threshold voltage becomes slow at the response rate. To decrease a response time, it is recommendable to reduce a thickness (d) of a cell for the liquid crystal display device. However, it is necessary to set a value expressed by a product (Δn·d) of a cell thickness (d) and an optical anisotropy (Δn) of the liquid crystal composition at a predetermined value of about 0.5 in order to obtain high contrast under the first-minimum condition for TN mode, as shown in the above item (3). Reducing a cell thickness necessitates an increase in an optical anisotropy of the liquid crystal composition. The compositions disclosed in Japanese Patent Kokai 8-73857 have the problems that the threshold voltage is low, the optical anisotropy is moderately large, but the upper-limit temperature of a nematic phase is too low and the voltage holding ratio at high temperatures is low, or they have the problems that the optical anisotropy is moderately large, the upper-limit temperature of a nematic phase is high, but the threshold voltage is too high and the voltage holding ratio at high temperatures is low, as shown in comparative examples which will be given later. The compositions disclosed in Japanese Patent Kokai 9-31460 have the problems that the optical anisotropy is small, the threshold voltage is high and the upper-limit temperature of a nematic phase is low, as shown in comparative examples which will be given later. The liquid crystal compositions for AM-LCD disclosed in WO 96/11897, those in which no compound having a cyano group at the end group is contained have the problems that the threshold voltage is not sufficiently low and the optical anisotropy is small, as shown in comparative examples which will be given later. (The compounds having a cyano group cannot be used as the liquid crystal composition for AM-LCD, because of the voltage holding ratio being low.) Thus a liquid crystal composition for AM-LCD has not been known which satisfies the requirements of keeping the voltage holding ratio at high temperatures high, having sufficiently low threshold voltage and large optical, as shown in comparative examples which will be given lateranisotropy, while satisfying the characteristics (1) to (4) as mentioned above. SUMMARY OF THE INVENTION An object of the invention is to provide a liquid crystal composition especially having high voltage holding ratio at high temperatures, sufficiently low threshold voltage and large optical anisotropy, while satisfying general characteristics required for AM-LCD. Through our intensive studies on compositions using various liquid crystalline compounds in an effort to solve the above-mentioned problems, we have found that the above object can be achieved by using the liquid crystal composition of the present invention in a display device for AM-LCD. DETAILED DESCRIPTION OF THE INVENTION The present invention provides a liquid crystal composition which comprises: as a first component at least one of the compounds of the following formulas (1-1) and (1-2); and as a second component at least one of the compounds of the following formulas (2-1) to (2-3)  in which R 1 , R 2 , R 3 , R 4 and R 5 each independently represent an alkyl group of 1-10 carbons; A 1 , A 2 , A 3 , A 4 , A 5 and A 6 each independently represent —CH 2 CH 2 — or a single bond, provided that at least one of A 3 and A 4 is a single bond; X 1 and X 3 each independently represent F, —OCF 3 or —OCF 2 H; and X 2 and X 4 each independently represent H or F. In one embodiment of the liquid crystal composition, the first component comprises 20-70% by weight and the second component comprises 30-80% by weight, based on the total weight of the liquid crystal composition. The liquid crystal composition of the invention may further comprise as a third component at least one of the compounds of the following formula (3) wherein R 6 and R 7 each independently represent an alkyl group of 1-10 carbons. In one embodiment of said liquid crystal composition, the first component comprises 20-70% by weight, the second component comprises 30-80% by weight and the third component comprises not more than 20% by weight, preferably 5 to 15% by weight, based on the total weight of the liquid crystal composition. Further, the present invention provides a liquid crystal display device using each of the above-described liquid crystal compositions according to the present invention. PREFERRED EMBODIMENTS OF THE INVENTION Preferred examples of the compounds of formula (1-1) used in the liquid crystal composition of the invention can include those of the following formulas (1-1-1) to (1-1-12): in which R represents an alkyl group of 1-10 carbons. Preferred examples of the compounds of formula (1-2) used in the liquid crystal composition of the invention can include those of the following formulas (1-2-1) to (1-2-12): in which R represents an alkyl group of 1-10 carbons. Preferred examples of the compounds of formula (2-1) used in the liquid crystal composition of the invention can include those of the following formulas (2-1-1) to (2-1-3): in which R represents an alkyl group of 1-10 carbons. Preferred examples of the compounds of formula (2-2) used in the liquid crystal composition of the invention can include those of the following formulas (2-2-1) to (2-2-2): in which R represents an alkyl group of 1-10 carbons. Preferred examples of the compounds of formula (2-3) used in the liquid crystal composition of the invention can include those of the following formulas (2-3-1) to (2-3-2): in which R represents an alkyl group of 1-10 carbons. Preferred examples of the compounds of formula (3) used in the liquid crystal composition of the invention can include those of the following formula (3-1): wherein R and R′ each independently represent an alkyl group of 1-10 carbons. The object for using each compound constituting the liquid crystal composition of the invention will be explained below. The compounds of formula (1-1) are characterized in that the dielectric anisotropy is considerably large, the viscosity is relatively low, the optical anisotropy is relatively large and the specific resistance is high. Thus the compounds of formula (1-1) are used for the purpose of keeping the viscosity relatively low, increasing the optical anisotropy to a relatively large level and reducing the threshold voltage to a considerably low level, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high. The compounds of formula (1-2) are characterized in that the dielectric anisotropy is considerably large, the viscosity is relatively low, the optical anisotropy is relatively large, the specific resistance is high and the upper-limit temperature of a nematic phase is higher than the compounds of formula (1-1). Thus the compounds of formula (1-2) are used for the purpose of keeping the viscosity relatively low and reducing the threshold voltage to a considerably low level while maintaining the voltage holding ratio at high temperatures of the liquid crystal composition high, and further increasing the upper-limit temperature of a nematic phase high while keeping the optical anisotropy relatively large. The compounds of formula (2-1) are characterized in that the positive dielectric anisotropy is smaller than the compounds of formulas (1-1) and (1-2), and the viscosity is lower and the specific resistance is higher than the compounds of formulas (1-1) and (1-2), and further the optical anisotropy is smaller than the compounds of formulas (1-1) and (1-2). Thus the compounds of formula (2-1) are used for the purpose of reducing the viscosity, adjusting the threshold voltage and the optical anisotropy, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high. The compounds of formula (2-2) are characterized in that the positive dielectric anisotropy is smaller than the compounds of formulas (1-1) and (1-2), the viscosity is lower than the compounds of formula (1-1) or (1-2) and the specific resistance is higher than the compounds of formulas (1-1) and (1-2) and further the optical anisotropy is substantially equal to that of the compounds of formulas (1-1) and (1-2). Thus the compounds of formula (2-2) are used for the purpose of reducing the viscosity, adjusting the threshold voltage and more increasing the optical anisotropy, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high. The compounds of formula (2-3) are characterized in that the positive dielectric anisotropy is smaller and the specific resistance is higher, than those of the compounds of formulas (1-1) and (1-2) and the upper-limit temperature of a nematic phase is higher than that of the compounds of formula (2-2). Thus the compounds of formula (2-3) are used for the purpose of increasing the upper-limit temperature of a nematic phase and adjusting the threshold voltage, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high. The compounds of formula (3) are characterized in that the dielectric anisotropy is approximately zero, the specific resistance is high, the optical anisotropy is considerably large and the upper-limit temperature of a nematic phase is considerably high. Thus the compounds of formula (3) are used for the purpose of increasing the upper-limit temperature of a nematic phase, adjusting the threshold voltage and increasing the optical anisotropy, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high. A preferable component ratio of each compound constituting the liquid crystal composition of the present invention and the reason therefor will be explained below. Incorporating a large quantity of the compounds of formula (1-1) or (1-2) into the liquid crystal composition may result in raising the lower-limit temperature of a nematic phase in the liquid crystal composition. For this reason, it is desirable that the compounds of formula (1-1) or (1-2) constitute not more than 70% by weight of the liquid crystal composition. Further, it is desirable that the compounds of formula (1-1) or (1-2) constitute not less than 20% by weight of the liquid crystal composition in order to reduce the threshold voltage while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high. Incorporating a large quantity of the compounds of formulas (2-1) to (2-3) into the liquid crystal composition may result in raising the lower-limit temperature of a nematic phase in the liquid crystal composition. For this reason, it is desirable that the compounds of formulas (2-1) to (2-3) constitute not more than 80% by weight of the liquid crystal composition. Further, it is desirable that the compounds of formulas (2-1) to (2-3) constitute not less than 30% by weight of the liquid crystal composition in order to reduce the viscosity or increase the upper-limit temperature of a nematic phase while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high and keeping the threshold voltage low. Incorporating a large quantity of the compounds of formula (3) into the liquid crystal composition may result in raising the lower-limit temperature of a nematic phase in the liquid crystal composition and increasing the threshold voltage. For this reason, it is desirable that the compounds of formula (3) constitute not more than 20% by weight, preferably 5 to 15% by weight, of the liquid crystal composition. Each of the compounds constituting the composition of the present invention can be synthesized by the prior art processes. Of the compounds of formulas (1-1) and (1-2), the method of synthesizing those of formulas (1-1-4) and (1-2-4) is disclosed in Japanese Patent Kokai 9-72708. Of the compounds of formulas (2-1), (2-2) and (2-3), the method of synthesizing those of formulas (2-1-1), (2-2-1) and (2-3-2) is disclosed in Japanese Patent Kokai 2-233626. Of the compounds of formula (3), the method of synthesizing those of formula (3-1) is disclosed in Japanese Patent Kokai 2-237949. Other liquid crystalline compounds than the compounds represented by the above-mentioned formulas can be used in admixture therewith in the liquid crystal composition within the range not injuring the object of the present invention. To the liquid crystal composition of the present invention may be added chiral dopants such as cholesteric nonanoate for the purpose of inducing the helical structure of liquid crystal molecules to adjust necessary twist angle. The liquid crystal composition of the invention can be also used as a liquid crystal composition for guest-host (GH) mode by incorporating therein dichroic dyes such as those of merocyanines, styryl derivatives, azo compounds, azomethines, azoxy compounds, quinophthalones, anthraquinones and tetrazine derivatives, etc. Also, the liquid crystal composition of the invention can be used as a liquid crystal composition for a polymer-dispersion type display device and for electrically controlled birefringence (ECB) mode and dynamic scattering (DS) mode. Further, the present composition can be used as a liquid crystal composition for an in-plain switching mode. The liquid crystal composition of the invention is prepared by a process conventional per se. In general, a process can be employed wherein various compounds are mixed and dissolved each other at an elevated temperature. This invention is further illustrated by the following examples and comparative examples in which all parts and percentages (%) are by weight unless otherwise indicated. Further, the compounds used in the Examples and Comparative Examples are expressed by the symbols as shown below. Indication of the Compounds Using the Symbols R—(A 1 )—Z 1 —. . . —Z n —(A n )—X 1) Left terminal group R— Symbol C n H 2n+1 — n- 2) Ring structure —(A 1 )—, —(A n )— Symbol H B B(F) B(F,F) 3) Linking group —Z 1 —, —Z n — Symbol —CH 2 CH 2 — 2 —COO— E —C≡C— T —CF 2 O— CF2O —CH═CH— V 4) Right terminal group —X Symbol —F —F —C n H 2n+1 -n —Cl —CL —CF 3 —CF3 —OCF 3 —OCF3 —OCF 2 H —OCF2H 5) Example of indication 3-HB(F,F)CF2OB(F,F)—F: 3-HHB(F,F)—F: For the characteristics of the liquid crystal composition, the upper limit of the nematic phase transition temperature was expressed as T NI , the lower limit of the nematic phase transition temperature was expressed as T c , the viscosity was expressed as η, the optical anisotropy was expressed as Δn, the threshold voltage was expressed as Vth, the voltage holding ratio at 25° C. was expressed as VHR(25), the voltage holding ratio at 100° C. was expressed as VHR(100), the voltage holding ratio at 120° C. was expressed as VHR(120) and the response rate was expressed as τ. T NI was determined by measuring the temperature of a nematic-isotropic phase transition during the temperature rising process using a polarization microscope. T c was judged by a liquid crystal phase which appeared after the liquid crystal composition was allowed to stand for 30 days in a freezer at 10° C., 0° C., −10° C., −20° C., −30° C. and −40° C., respectively. For example, when a liquid crystal composition is in a nematic state at −20° C., and in a crystallized or smectic state at −30° C., T c of the liquid crystal composition was expressed as <−20° C. η was measured at 20° C. Δn was measured at 25° C. by using a lamp with a wavelength of 589 nm for light source. Vth was measured at 25° C. Vth refers to the value of voltage applied when a rectangular wave having a frequency of 32 Hz is applied in the normally white mode using a cell having a cell gap of (0.4/Δn) μm and a twist angle of 80° and a transmittance of light passing through the cell becomes 90%. The voltage holding ratio was determined in accordance with the area method. τ was measured at a voltage applied where the response time of the liquid crystal rising (τ on) and the response time of the liquid crystal falling (τ off) becomes equal when cholesteryl nonanoate was added to the liquid crystal composition so that a pitch in the twist becomes 80 μm and the thus prepared composition was placed in a cell having a cell gap of (0.4/Δn) μm and a twist angle of 90°, to which a rectangular wave having a frequency of 32 Hz was applied. In this case, τ was measured at 25° C., and defined as a sum of the values τ on and τ off. Comparative Example 1 The composition (Example 6) with the highest T NI of the compositions disclosed in Japanese Patent Kokai 8-73857 was prepared in the following manner. 2-HBEB(F,F)-F 5% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 5% 3-BBEB(F,F)-F 5% 2-HHB-CL 5% 4-HHB-CL 10% 5-HHB-CL 5% 3-H2BB(F,F)-F 10% 5-H2BB(F,F)-F 10% 3-HBB(F,F)-F 10% 5-HBB(F,F)-F 10% 3-HH2B(F,F)-F 5% 2-HHBB(F,F)-F 5% 3-HH2BB(F,F)-F 5% 4-HH2BB(F,F)-F 5% The above composition had the following characteristics: T NI =113.6° C. T c <0° C. η=38.3 mPa·s Δn=0.133 Vth=1.64 V VHR(25)=98.3% VHR(120)=90.1% τ=40 ms This composition had high T NI , large Δn and relatively short response time, but high Vth, low VHR at high temperatures and high T c . Comparative Example 2 The composition (Example 2) with the lowest Vth of the compositions disclosed in Japanese Patent Kokai 8-73857 was prepared in the following manner. 5-HHEB(F,F)-F 5% 2-HBEB(F,F)-F 5% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 5% 3-BBEB(F,F)-F 5% 4-BBEB(F,F)-F 5% 5-BBEB(F,F)-F 5% 4-HEB(F,F)-F 10% 4-HB-CL 10% 7-HB(F)-F 3% 7-HB(F,F)-F 9% 3-HBB(F,F)-F 10% 5-HHB(F,F)-F 10% 3-H2BB(F,F)-F 13% The above composition had the following characteristics: T NI =46.1° C. T c <−10° C. η=36.3 mPa·s Δn =0.096 Vth=0.91 V VHR(25)=98.3% VHR(100)=92.3% τ=60 ms This composition had low Vth, but low T NI , low VHR at high temperatures, small Δn and long response time. Comparative Example 3 The composition (Example 5) with the highest T NI of the compositions disclosed in Japanese Patent Kokai 9-31460 was prepared in the following manner. 3-HHB(F,F)-F 10% 4-HHB(F,F)-F 5% 3-H2HB(F,F)-F 10% 5-H2HB(F,F)-F 9% 3-HH2B(F,F)-F 11% 5-HH2B(F,F)-F 7% 3-HBB(F,F)-F 8% 5-HBB(F,F)-F 8% 3-H2BB(F,F)-F 4% 5-H2BB(F,F)-F 4% 3-HBEB(F,F)-F 3% 4-HBEB(F,F)-F 3% 3-HHEB(F,F)-F 10% 4-H.HEB(F,F)-F 4% 5-HHEB(F,F)-F 4% The above composition had the following characteristics: T NI =83.7° C. T c <−30° C. η=28.5 mPa·s Δn=0.090 Vth=1.21 V VHR(25)=98.3% VHR(100)=91.8% τ=59 ms This composition had relatively high T NI , but high Vth, small Δn and long response time. Comparative Example 4 The composition (Example 7) with the lowest Vth of the compositions disclosed in Japanese Patent Kokai 9-31460 was prepared in the following manner. 7-HB(F,F)-F 7% 3-HHB(F,F)-F 7% 3-H2HB(F,F)-F 3% 3-HH2B(F,F)-F 7% 5-HH2B(F,F)-F 5% 3-HBB(F,F)-F 21% 5-HBB(F,F)-F 21% 2-HBEB(F,F)-F 3% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 3% 3-HHEB(F,F)-F 10% 4-HHEB(F,F)-F 3% 5-HHEB(F,F)-F 5% The above composition had the following characteristics: T NI =61.4° C. T c <−30° C. η=30.7 mPa·s Δn=0.094 Vth=1.05 V VHR(25)=98.3% VHR(100)=92.5% τ=51 ms This composition had low Vth, but low T NI , small Δn and low VHR at high temperatures. Comparative Example 5 The composition (Example 12) with the largest Δn of the compositions disclosed in Japanese Patent Kokai 9-31460 was prepared in the following manner. 7-HB(F,F)-F 9% 3-HHB(F,F)-F 10% 3-HH2B(F,F)-F 7% 5-HH2B(F,F)-F 5% 3-HBB(F,F)-F 18% 5-HBB(F,F)-F 18% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 3% 3-HHEB(F,F)-F 8% 5-HHEB(F,F)-F 5% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 5-HH2BB(F,F)-F 4% The above composition had the following characteristics: T NI =78.3° C. T c <−30° C. η=30.2 mPa·s Δn=0.103 Vth=1.21 V VHR(25)=98.4% VHR(100)=91.5% τ=49 ms This composition had relatively small Δn, high threshold voltage and low VHR at high temperatures. Comparative Example 6 The composition (Example 36) with the lowest Vth of the compositions disclosed in WO 96/11897 was prepared in the following manner. 3-HBCF2OB(F,F)-F 5% 5-HBCF2OB(F,F)-F 10% 5-HBCF2OB-CF3 5% 5-HBCF2OB(F)-F 5% 3-HBCF2OB-OCF3 5% 7-HB(F,F)-F 8% 3-HHB(F,F)-F 6% 4-HHB(F,F)-F 3% 3-H2HB(F,F)-F 10% 4-H2HB(F,F)-F 6% 5-H2HB(F,F)-F 6% 3-HH2B(F,F)-F 10% 5-HH2B(F,F)-F 5% 3-HBB(F,F)-F 5% 5-HBB(F,F)-F 5% 3-HHBB(F,F)-F 3% 3-HH2BB(F,F)-F 3% The above composition had the following characteristics: T NI =61.8° C. T c <−20 C. η=23.6 mPa·s Δn=0.083 Vth=1.50 V VHR(25)=98.7% VHR(100)=95.6% τ=40 ms This composition had low viscosity, but small Δn, high threshold voltage and low T NI . Comparative Example 7 The composition (Example 37) with the largest Δn of the compositions disclosed in WO 96/11897 was prepared in the following manner. 3-HBCF2OB(F,F)-F 5% 3-HBCF2OB-OCF3 5% 3-HB-CL 4% 5-HB-CL 4% 7-HB-CL 5% 2-HHB-CL 6% 3-HHB-CL 7% 5-HHB-CL 6% 2-HBB(F)-F 6% 3-HBB(F)-F 6% 5-HBB(F)-F 12% 3-HBB(F,F)-F 13% 5-HBB(F,F)-F 13% 3-H2HB(F)-CL 3% 3-HB(F)TB-2 3% 3-HB(F)VB-2 2% The above composition had the following characteristics: T NI =89.3° C. T c <−20° C. η=21.9 mPa·s Δn=0.128 Vth=2.08 V VHR(25)=98.4% VHR(100)=93.5% τ=30 ms This composition had low viscosity and large Δn, but high threshold voltage and somewhat low VHR at high temperatures. EXAMPLE 1 The following liquid crystal composition was prepared. First Component 2-HB(F,F)CF2OB(F,F)-F 15% 3-HB(F,F)CF2OB(F,F)-F 15% 4-HB(F,F)CF2OB(F,F)-F 15% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HBB(F,F)-F 10% 2-HHBB(F,F)-F 5% 3-HHBB(F,F)-F 5% 4-HHBB(F,F)-F 5% 5-HHBB(F,F)-F 5% 3-HH2BB(F,F)-F 5% The above composition had the following characteristics: T NI =84.2° C. T c <−20° C. η=44.0 mPa·s Δn=0.106 Vth=1.04 V VHR(25)=98.7% VHR(100)=95.1% τ=57 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 2 The following liquid crystal composition was prepared. First Component 3-HB(F,F)CF2OB(F,F)-F 6% 5-HB(F,F)CF2OB(F,F)-F 5% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HHB(F,F)-F 5% 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)-F 19% 5-HBB(F,F)-F 19% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 4-HHBB(F,F)-F 3% The above composition had the following characteristics: T NI =80.6° C. T c <−30° C. τ=39.0 mPa·s Δn=0.110 Vth=1.20 V VHR(25)=98.7% VHR(100)=95.8% τ=40 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 3 The following liquid crystal composition was prepared. First Component 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% 2-HH2B(F,F)CF2OB(F,F)-F 4% 3-HH2B(F,F)CF2OB(F,F)-F 4% Second Component 3-HBB(F,F)-F 27% 5-HBB(F,F)-F 27% 3-H2BB(F,F)-F 5% 5-H2BB(F,F)-F 5% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% The above composition had the following characteristics: T NI =77.1° C. T c <−20° C. η=44.0 mPa·s Δn=0.123 Vth=1.19 V VHR(25)=98.7% VHR(100)=96.2% τ=45 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 4 The following liquid crystal composition was prepared. First Component 3-HB(F,F)CF2OB(F)-OCF3 4% 4-HB(F,F)CF2OB(F)-OCF3 4% 5-HB(F,F)CF2OB(F)-OCF3 3% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HH2B(F,F)-F 5% 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)-F 19% 5-HBB(F,F)-F 19% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 4-HHBB(F,F)-F 3% The above composition had the following characteristics: T NI =84.0° C. T c <−30° C. η=38.0 mPa·s Δn=0.112 Vth=1.23 V VHR(25)=98.7% VHR(100)=96.0% τ=38 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 5 The following liquid crystal composition was prepared. First Component 2-HHB(F,F)CF2OB(F)-F 5% 3-HHB(F,F)CF2OB(F)-F 5% 2-HHB(F,F)CF2OB(F)-OCF3 5% 3-HHB(F,F)CF2OB(F)-OCF3 5% 2-HHB(F,F)CF2OB(F,F)-F 4% 3-HHB(F,F)CF2OB(F,F)-F 4% Second Component 3-HBB(F,F)-F 27% 5-HBB(F,F)-F 27% 3-H2BB(F,F)-F 5% 5-H2BB(F,F)-F 5% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% The above composition had the following characteristics: T NI =79.3° C. T c <−20° C. η=42.0 mPa·s Δn=0.125 Vth=1.20 V VHR(25)=98.7% VHR(100)=95.5% τ=42 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 6 The following liquid crystal composition was prepared. First Component 3-HB(F,F)CF2OB(F)-F 3% 3-HB(F,F)CF2OB(F)-OCF2H 2% 3-HB(F,F)CF2OB(F,F)-OCF3 2% 3-H2B(F,F)CF2OB(F,F)-F 2% 3-HB(F,F)CF2OB(F,F)-OCF2H 2% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HH2B(F,F)-F 5% 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)-F 19% 5-HBB(F,F)-F 19% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 4-HHBB(F,F)-F 3% The above composition had the following characteristics: T NI =85.3° C. T c <−20° C. η=38.5 mPa·s Δn=0.120 Vth=1.21 V VHR(25)=98.5% VHR(100)=95.9% τ=36 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 7 The following liquid crystal composition was prepared. First Component 2-H2B(F,F)CF2OB(F)-F 2% 3-H2B(F,F)CF2OB(F)-OCF3 2% 2-H2B(F,F)CF2OB(F,F)-OCF3 2% 2-HB(F,F)CF2OB(F,F)-F 10% 3-HB(F,F)CF2OB(F,F)-F 14% 4-HB(F,F)CF2OB(F,F)-F 15% 2-HHB(F,F)CF2OB(F)-OCF2H 2% 3-HHB(F,F)CF2OB(F,F)OCF3 2% 2-HHB(F,F)CF2OB(F,F)-F 4% 3-HHB(F,F)CF2OB(F,F)-F 4% 4-HHB(F,F)CF2OB(F,F)-F 4% 5-HHB(F,F)CF2OB(F,F)-F 4% Second Component 3-HBB(F,F)-F 10% 2-HHBB(F,F)-F 5% 3-HHBB(F,F)-F 5% 4-HHBB(F,F)-F 5% 5-HHBB(F,F)-F 5% 3-HH2BB(F,F)-F 5% The above composition had the following characteristics: T NI =85.0° C. T c <−20° C. η=41.0 mPa·s Δn=0.110 Vth=1.12 V VHR(25)=98.7% VHR(100)=95.3% τ=52 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 8 The following liquid crystal composition was prepared. First Component: 2-HB(F,F)CF2OB(F,F)-F 15% 3-HB(F,F)CF2OB(F,F)-F 15% 4-HB(F,F)CF2OB(F,F)-F 15% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component: 3-HBB(F,F)-F 10% 2-HHBB(F,F)-F 5% 3-HHBB(F,F)-F 5% 4-HHBB(F,F)-F 5% 5-HHBB(F,F)-F 5% Third Component: 5-HBB(F)B-2 5% The above composition had the following characteristics: T NI =84.2° C. T c <−20° C. η=43.6 mPa·s Δn=0.111 Vth=1.12 V VHR(25)=98.7% VHR(100)=96.1% τ=49 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. EXAMPLE 9 The following liquid crystal composition was prepared. First Component: 3-HB(F,F)CF2OB(F,F)-F 6% 5-HB(F,F)CF2OB(F,F)-F 5% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component: 3-HHB(F,F)-F 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)F 19% 5-HBB(F,F)-F 19% Third Component: 5-HBB(F)B-2 6% 5-HBB(F)B-3 5% The above composition had the following characteristics: T NI =80.6° C. T c <−20° C. η=36.8 mPa·s Δn=0.121 Vth=1.26 V VHR(25)=98.7% VHR(100)=95.6% τ=39 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ. As shown in the above Examples, the present invention can provide the liquid crystal compositions for AM-LCD, especially having high voltage holding ratio at high temperatures, sufficiently low threshold voltage and large optical anisotropy, while satisfying general characteristics required for the AM-CD display mode.
A novel liquid crystal composition comprising three components: at least one difluoro-oxymethane derivative, at least one trifluorophenyl derivative and a monofluorophenyl dervivative. The composition exhibits a high voltage holding ratio at high temperatures, sufficiently low threshold voltage and large optical anisotropy, while satisfying general characteristics required for the AM-LCD display mode.
Identify the most important claim in the given context and summarize it
[ "This appln is a cont of Ser.", "No. 09/388,445 filed Sep. 2, 1999, abn.", "FIELD OF THE INVENTION This invention relates to a nematic liquid crystal composition.", "More particularly, the invention relates to a liquid crystal composition suitable for an active-matrix (AM) mode and to a liquid crystal display device using the liquid crystal composition.", "BACKGROUND OF THE INVENTION The liquid crystal display device of the active-matrix mode (AM-LCD) is the center of attention as the favorite of LCD, since it permits a high-definition display.", "It has been applied for a display screen of laptop computers, digital still camera, digital video camera and the like.", "The AM-LCD liquid crystal compositions have required the following characteristics (1) to (5).", "(1) The liquid crystal composition should exhibit a nematic phase in as wide a temperature range as possible in order to extend an environmental temperature at which the liquid crystal display device is used.", "(The upper-limit temperature of the nematic phase is increased as high as possible and the lower-limit temperature of the nematic phase is reduced as low as possible.) (2) A viscosity of the liquid crystal composition should be reduced as low as possible in order to decrease a response time of the liquid crystal display device.", "(3) An optical anisotropy (Δn) of the liquid crystal composition can take a suitable value depending on a cell thickness (d) of the liquid crystal display device in order to increase a contrast of the liquid crystal display device.", "(4) A specific resistance of the liquid crystal composition should be increased and a voltage holding ratio of a cell in which the liquid crystal composition is contained should be increased in order to increase a contrast of the liquid crystal display device.", "In particular, a voltage holding ratio at high temperatures should be increased.", "The measurement of the voltage holding ratio at high temperatures is equivalent to an accelerated test to make sure of the durability of the liquid crystal composition.", "(5) A threshold voltage of the liquid crystal composition should be reduced in order to provide a smaller-sized battery serving as a power for driving the liquid crystal display device.", "In view of such background, Japanese Patent Kokai 8-73857 discloses the liquid crystal compositions having high voltage holding ratios, low threshold voltage and moderately large optical anisotropy.", "Japanese Patent Kokai 9-31460 also discloses the liquid crystal compositions particularly having low threshold voltage, good compatibility at low temperatures and a wide temperature range of a nematic phase.", "As liquid crystal compounds for low-voltage driving in various modes including AM and STN modes, WO 96/11897 discloses new liquid crystalline compounds having large dielectric anisotropy and very low viscosity as well as liquid crystal compositions containing said compounds.", "The liquid crystalline compounds having large dielectric anisotropy are required to use in order to reduce the threshold voltage of the liquid crystal composition.", "In general, the use of the liquid crystalline compounds having large dielectric anisotropy for the preparation of the liquid crystal composition increases the viscosity of the liquid crystal composition.", "A response time is proportional to the square of a cell gap, as proposed by E. Jakeman et al.", ", Phys.", "Lett.", ", 39A (1972) 69.", "Accordingly, the liquid crystal display device using the liquid crystal composition having reduced threshold voltage becomes slow at the response rate.", "To decrease a response time, it is recommendable to reduce a thickness (d) of a cell for the liquid crystal display device.", "However, it is necessary to set a value expressed by a product (Δn·d) of a cell thickness (d) and an optical anisotropy (Δn) of the liquid crystal composition at a predetermined value of about 0.5 in order to obtain high contrast under the first-minimum condition for TN mode, as shown in the above item (3).", "Reducing a cell thickness necessitates an increase in an optical anisotropy of the liquid crystal composition.", "The compositions disclosed in Japanese Patent Kokai 8-73857 have the problems that the threshold voltage is low, the optical anisotropy is moderately large, but the upper-limit temperature of a nematic phase is too low and the voltage holding ratio at high temperatures is low, or they have the problems that the optical anisotropy is moderately large, the upper-limit temperature of a nematic phase is high, but the threshold voltage is too high and the voltage holding ratio at high temperatures is low, as shown in comparative examples which will be given later.", "The compositions disclosed in Japanese Patent Kokai 9-31460 have the problems that the optical anisotropy is small, the threshold voltage is high and the upper-limit temperature of a nematic phase is low, as shown in comparative examples which will be given later.", "The liquid crystal compositions for AM-LCD disclosed in WO 96/11897, those in which no compound having a cyano group at the end group is contained have the problems that the threshold voltage is not sufficiently low and the optical anisotropy is small, as shown in comparative examples which will be given later.", "(The compounds having a cyano group cannot be used as the liquid crystal composition for AM-LCD, because of the voltage holding ratio being low.) Thus a liquid crystal composition for AM-LCD has not been known which satisfies the requirements of keeping the voltage holding ratio at high temperatures high, having sufficiently low threshold voltage and large optical, as shown in comparative examples which will be given lateranisotropy, while satisfying the characteristics (1) to (4) as mentioned above.", "SUMMARY OF THE INVENTION An object of the invention is to provide a liquid crystal composition especially having high voltage holding ratio at high temperatures, sufficiently low threshold voltage and large optical anisotropy, while satisfying general characteristics required for AM-LCD.", "Through our intensive studies on compositions using various liquid crystalline compounds in an effort to solve the above-mentioned problems, we have found that the above object can be achieved by using the liquid crystal composition of the present invention in a display device for AM-LCD.", "DETAILED DESCRIPTION OF THE INVENTION The present invention provides a liquid crystal composition which comprises: as a first component at least one of the compounds of the following formulas (1-1) and (1-2);", "and as a second component at least one of the compounds of the following formulas (2-1) to (2-3) in which R 1 , R 2 , R 3 , R 4 and R 5 each independently represent an alkyl group of 1-10 carbons;", "A 1 , A 2 , A 3 , A 4 , A 5 and A 6 each independently represent —CH 2 CH 2 — or a single bond, provided that at least one of A 3 and A 4 is a single bond;", "X 1 and X 3 each independently represent F, —OCF 3 or —OCF 2 H;", "and X 2 and X 4 each independently represent H or F. In one embodiment of the liquid crystal composition, the first component comprises 20-70% by weight and the second component comprises 30-80% by weight, based on the total weight of the liquid crystal composition.", "The liquid crystal composition of the invention may further comprise as a third component at least one of the compounds of the following formula (3) wherein R 6 and R 7 each independently represent an alkyl group of 1-10 carbons.", "In one embodiment of said liquid crystal composition, the first component comprises 20-70% by weight, the second component comprises 30-80% by weight and the third component comprises not more than 20% by weight, preferably 5 to 15% by weight, based on the total weight of the liquid crystal composition.", "Further, the present invention provides a liquid crystal display device using each of the above-described liquid crystal compositions according to the present invention.", "PREFERRED EMBODIMENTS OF THE INVENTION Preferred examples of the compounds of formula (1-1) used in the liquid crystal composition of the invention can include those of the following formulas (1-1-1) to (1-1-12): in which R represents an alkyl group of 1-10 carbons.", "Preferred examples of the compounds of formula (1-2) used in the liquid crystal composition of the invention can include those of the following formulas (1-2-1) to (1-2-12): in which R represents an alkyl group of 1-10 carbons.", "Preferred examples of the compounds of formula (2-1) used in the liquid crystal composition of the invention can include those of the following formulas (2-1-1) to (2-1-3): in which R represents an alkyl group of 1-10 carbons.", "Preferred examples of the compounds of formula (2-2) used in the liquid crystal composition of the invention can include those of the following formulas (2-2-1) to (2-2-2): in which R represents an alkyl group of 1-10 carbons.", "Preferred examples of the compounds of formula (2-3) used in the liquid crystal composition of the invention can include those of the following formulas (2-3-1) to (2-3-2): in which R represents an alkyl group of 1-10 carbons.", "Preferred examples of the compounds of formula (3) used in the liquid crystal composition of the invention can include those of the following formula (3-1): wherein R and R′ each independently represent an alkyl group of 1-10 carbons.", "The object for using each compound constituting the liquid crystal composition of the invention will be explained below.", "The compounds of formula (1-1) are characterized in that the dielectric anisotropy is considerably large, the viscosity is relatively low, the optical anisotropy is relatively large and the specific resistance is high.", "Thus the compounds of formula (1-1) are used for the purpose of keeping the viscosity relatively low, increasing the optical anisotropy to a relatively large level and reducing the threshold voltage to a considerably low level, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high.", "The compounds of formula (1-2) are characterized in that the dielectric anisotropy is considerably large, the viscosity is relatively low, the optical anisotropy is relatively large, the specific resistance is high and the upper-limit temperature of a nematic phase is higher than the compounds of formula (1-1).", "Thus the compounds of formula (1-2) are used for the purpose of keeping the viscosity relatively low and reducing the threshold voltage to a considerably low level while maintaining the voltage holding ratio at high temperatures of the liquid crystal composition high, and further increasing the upper-limit temperature of a nematic phase high while keeping the optical anisotropy relatively large.", "The compounds of formula (2-1) are characterized in that the positive dielectric anisotropy is smaller than the compounds of formulas (1-1) and (1-2), and the viscosity is lower and the specific resistance is higher than the compounds of formulas (1-1) and (1-2), and further the optical anisotropy is smaller than the compounds of formulas (1-1) and (1-2).", "Thus the compounds of formula (2-1) are used for the purpose of reducing the viscosity, adjusting the threshold voltage and the optical anisotropy, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high.", "The compounds of formula (2-2) are characterized in that the positive dielectric anisotropy is smaller than the compounds of formulas (1-1) and (1-2), the viscosity is lower than the compounds of formula (1-1) or (1-2) and the specific resistance is higher than the compounds of formulas (1-1) and (1-2) and further the optical anisotropy is substantially equal to that of the compounds of formulas (1-1) and (1-2).", "Thus the compounds of formula (2-2) are used for the purpose of reducing the viscosity, adjusting the threshold voltage and more increasing the optical anisotropy, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high.", "The compounds of formula (2-3) are characterized in that the positive dielectric anisotropy is smaller and the specific resistance is higher, than those of the compounds of formulas (1-1) and (1-2) and the upper-limit temperature of a nematic phase is higher than that of the compounds of formula (2-2).", "Thus the compounds of formula (2-3) are used for the purpose of increasing the upper-limit temperature of a nematic phase and adjusting the threshold voltage, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high.", "The compounds of formula (3) are characterized in that the dielectric anisotropy is approximately zero, the specific resistance is high, the optical anisotropy is considerably large and the upper-limit temperature of a nematic phase is considerably high.", "Thus the compounds of formula (3) are used for the purpose of increasing the upper-limit temperature of a nematic phase, adjusting the threshold voltage and increasing the optical anisotropy, while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high.", "A preferable component ratio of each compound constituting the liquid crystal composition of the present invention and the reason therefor will be explained below.", "Incorporating a large quantity of the compounds of formula (1-1) or (1-2) into the liquid crystal composition may result in raising the lower-limit temperature of a nematic phase in the liquid crystal composition.", "For this reason, it is desirable that the compounds of formula (1-1) or (1-2) constitute not more than 70% by weight of the liquid crystal composition.", "Further, it is desirable that the compounds of formula (1-1) or (1-2) constitute not less than 20% by weight of the liquid crystal composition in order to reduce the threshold voltage while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high.", "Incorporating a large quantity of the compounds of formulas (2-1) to (2-3) into the liquid crystal composition may result in raising the lower-limit temperature of a nematic phase in the liquid crystal composition.", "For this reason, it is desirable that the compounds of formulas (2-1) to (2-3) constitute not more than 80% by weight of the liquid crystal composition.", "Further, it is desirable that the compounds of formulas (2-1) to (2-3) constitute not less than 30% by weight of the liquid crystal composition in order to reduce the viscosity or increase the upper-limit temperature of a nematic phase while keeping the voltage holding ratio at high temperatures of the liquid crystal composition high and keeping the threshold voltage low.", "Incorporating a large quantity of the compounds of formula (3) into the liquid crystal composition may result in raising the lower-limit temperature of a nematic phase in the liquid crystal composition and increasing the threshold voltage.", "For this reason, it is desirable that the compounds of formula (3) constitute not more than 20% by weight, preferably 5 to 15% by weight, of the liquid crystal composition.", "Each of the compounds constituting the composition of the present invention can be synthesized by the prior art processes.", "Of the compounds of formulas (1-1) and (1-2), the method of synthesizing those of formulas (1-1-4) and (1-2-4) is disclosed in Japanese Patent Kokai 9-72708.", "Of the compounds of formulas (2-1), (2-2) and (2-3), the method of synthesizing those of formulas (2-1-1), (2-2-1) and (2-3-2) is disclosed in Japanese Patent Kokai 2-233626.", "Of the compounds of formula (3), the method of synthesizing those of formula (3-1) is disclosed in Japanese Patent Kokai 2-237949.", "Other liquid crystalline compounds than the compounds represented by the above-mentioned formulas can be used in admixture therewith in the liquid crystal composition within the range not injuring the object of the present invention.", "To the liquid crystal composition of the present invention may be added chiral dopants such as cholesteric nonanoate for the purpose of inducing the helical structure of liquid crystal molecules to adjust necessary twist angle.", "The liquid crystal composition of the invention can be also used as a liquid crystal composition for guest-host (GH) mode by incorporating therein dichroic dyes such as those of merocyanines, styryl derivatives, azo compounds, azomethines, azoxy compounds, quinophthalones, anthraquinones and tetrazine derivatives, etc.", "Also, the liquid crystal composition of the invention can be used as a liquid crystal composition for a polymer-dispersion type display device and for electrically controlled birefringence (ECB) mode and dynamic scattering (DS) mode.", "Further, the present composition can be used as a liquid crystal composition for an in-plain switching mode.", "The liquid crystal composition of the invention is prepared by a process conventional per se.", "In general, a process can be employed wherein various compounds are mixed and dissolved each other at an elevated temperature.", "This invention is further illustrated by the following examples and comparative examples in which all parts and percentages (%) are by weight unless otherwise indicated.", "Further, the compounds used in the Examples and Comparative Examples are expressed by the symbols as shown below.", "Indication of the Compounds Using the Symbols R—(A 1 )—Z 1 —.", "—Z n —(A n )—X 1) Left terminal group R— Symbol C n H 2n+1 — n- 2) Ring structure —(A 1 )—, —(A n )— Symbol H B B(F) B(F,F) 3) Linking group —Z 1 —, —Z n — Symbol —CH 2 CH 2 — 2 —COO— E —C≡C— T —CF 2 O— CF2O —CH═CH— V 4) Right terminal group —X Symbol —F —F —C n H 2n+1 -n —Cl —CL —CF 3 —CF3 —OCF 3 —OCF3 —OCF 2 H —OCF2H 5) Example of indication 3-HB(F,F)CF2OB(F,F)—F: 3-HHB(F,F)—F: For the characteristics of the liquid crystal composition, the upper limit of the nematic phase transition temperature was expressed as T NI , the lower limit of the nematic phase transition temperature was expressed as T c , the viscosity was expressed as η, the optical anisotropy was expressed as Δn, the threshold voltage was expressed as Vth, the voltage holding ratio at 25° C. was expressed as VHR(25), the voltage holding ratio at 100° C. was expressed as VHR(100), the voltage holding ratio at 120° C. was expressed as VHR(120) and the response rate was expressed as τ.", "T NI was determined by measuring the temperature of a nematic-isotropic phase transition during the temperature rising process using a polarization microscope.", "T c was judged by a liquid crystal phase which appeared after the liquid crystal composition was allowed to stand for 30 days in a freezer at 10° C., 0° C., −10° C., −20° C., −30° C. and −40° C., respectively.", "For example, when a liquid crystal composition is in a nematic state at −20° C., and in a crystallized or smectic state at −30° C., T c of the liquid crystal composition was expressed as <−20° C. η was measured at 20° C. Δn was measured at 25° C. by using a lamp with a wavelength of 589 nm for light source.", "Vth was measured at 25° C. Vth refers to the value of voltage applied when a rectangular wave having a frequency of 32 Hz is applied in the normally white mode using a cell having a cell gap of (0.4/Δn) μm and a twist angle of 80° and a transmittance of light passing through the cell becomes 90%.", "The voltage holding ratio was determined in accordance with the area method.", "τ was measured at a voltage applied where the response time of the liquid crystal rising (τ on) and the response time of the liquid crystal falling (τ off) becomes equal when cholesteryl nonanoate was added to the liquid crystal composition so that a pitch in the twist becomes 80 μm and the thus prepared composition was placed in a cell having a cell gap of (0.4/Δn) μm and a twist angle of 90°, to which a rectangular wave having a frequency of 32 Hz was applied.", "In this case, τ was measured at 25° C., and defined as a sum of the values τ on and τ off.", "Comparative Example 1 The composition (Example 6) with the highest T NI of the compositions disclosed in Japanese Patent Kokai 8-73857 was prepared in the following manner.", "2-HBEB(F,F)-F 5% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 5% 3-BBEB(F,F)-F 5% 2-HHB-CL 5% 4-HHB-CL 10% 5-HHB-CL 5% 3-H2BB(F,F)-F 10% 5-H2BB(F,F)-F 10% 3-HBB(F,F)-F 10% 5-HBB(F,F)-F 10% 3-HH2B(F,F)-F 5% 2-HHBB(F,F)-F 5% 3-HH2BB(F,F)-F 5% 4-HH2BB(F,F)-F 5% The above composition had the following characteristics: T NI =113.6° C. T c <0° C. η=38.3 mPa·s Δn=0.133 Vth=1.64 V VHR(25)=98.3% VHR(120)=90.1% τ=40 ms This composition had high T NI , large Δn and relatively short response time, but high Vth, low VHR at high temperatures and high T c .", "Comparative Example 2 The composition (Example 2) with the lowest Vth of the compositions disclosed in Japanese Patent Kokai 8-73857 was prepared in the following manner.", "5-HHEB(F,F)-F 5% 2-HBEB(F,F)-F 5% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 5% 3-BBEB(F,F)-F 5% 4-BBEB(F,F)-F 5% 5-BBEB(F,F)-F 5% 4-HEB(F,F)-F 10% 4-HB-CL 10% 7-HB(F)-F 3% 7-HB(F,F)-F 9% 3-HBB(F,F)-F 10% 5-HHB(F,F)-F 10% 3-H2BB(F,F)-F 13% The above composition had the following characteristics: T NI =46.1° C. T c <−10° C. η=36.3 mPa·s Δn =0.096 Vth=0.91 V VHR(25)=98.3% VHR(100)=92.3% τ=60 ms This composition had low Vth, but low T NI , low VHR at high temperatures, small Δn and long response time.", "Comparative Example 3 The composition (Example 5) with the highest T NI of the compositions disclosed in Japanese Patent Kokai 9-31460 was prepared in the following manner.", "3-HHB(F,F)-F 10% 4-HHB(F,F)-F 5% 3-H2HB(F,F)-F 10% 5-H2HB(F,F)-F 9% 3-HH2B(F,F)-F 11% 5-HH2B(F,F)-F 7% 3-HBB(F,F)-F 8% 5-HBB(F,F)-F 8% 3-H2BB(F,F)-F 4% 5-H2BB(F,F)-F 4% 3-HBEB(F,F)-F 3% 4-HBEB(F,F)-F 3% 3-HHEB(F,F)-F 10% 4-H.", "HEB(F,F)-F 4% 5-HHEB(F,F)-F 4% The above composition had the following characteristics: T NI =83.7° C. T c <−30° C. η=28.5 mPa·s Δn=0.090 Vth=1.21 V VHR(25)=98.3% VHR(100)=91.8% τ=59 ms This composition had relatively high T NI , but high Vth, small Δn and long response time.", "Comparative Example 4 The composition (Example 7) with the lowest Vth of the compositions disclosed in Japanese Patent Kokai 9-31460 was prepared in the following manner.", "7-HB(F,F)-F 7% 3-HHB(F,F)-F 7% 3-H2HB(F,F)-F 3% 3-HH2B(F,F)-F 7% 5-HH2B(F,F)-F 5% 3-HBB(F,F)-F 21% 5-HBB(F,F)-F 21% 2-HBEB(F,F)-F 3% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 3% 3-HHEB(F,F)-F 10% 4-HHEB(F,F)-F 3% 5-HHEB(F,F)-F 5% The above composition had the following characteristics: T NI =61.4° C. T c <−30° C. η=30.7 mPa·s Δn=0.094 Vth=1.05 V VHR(25)=98.3% VHR(100)=92.5% τ=51 ms This composition had low Vth, but low T NI , small Δn and low VHR at high temperatures.", "Comparative Example 5 The composition (Example 12) with the largest Δn of the compositions disclosed in Japanese Patent Kokai 9-31460 was prepared in the following manner.", "7-HB(F,F)-F 9% 3-HHB(F,F)-F 10% 3-HH2B(F,F)-F 7% 5-HH2B(F,F)-F 5% 3-HBB(F,F)-F 18% 5-HBB(F,F)-F 18% 3-HBEB(F,F)-F 5% 5-HBEB(F,F)-F 3% 3-HHEB(F,F)-F 8% 5-HHEB(F,F)-F 5% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 5-HH2BB(F,F)-F 4% The above composition had the following characteristics: T NI =78.3° C. T c <−30° C. η=30.2 mPa·s Δn=0.103 Vth=1.21 V VHR(25)=98.4% VHR(100)=91.5% τ=49 ms This composition had relatively small Δn, high threshold voltage and low VHR at high temperatures.", "Comparative Example 6 The composition (Example 36) with the lowest Vth of the compositions disclosed in WO 96/11897 was prepared in the following manner.", "3-HBCF2OB(F,F)-F 5% 5-HBCF2OB(F,F)-F 10% 5-HBCF2OB-CF3 5% 5-HBCF2OB(F)-F 5% 3-HBCF2OB-OCF3 5% 7-HB(F,F)-F 8% 3-HHB(F,F)-F 6% 4-HHB(F,F)-F 3% 3-H2HB(F,F)-F 10% 4-H2HB(F,F)-F 6% 5-H2HB(F,F)-F 6% 3-HH2B(F,F)-F 10% 5-HH2B(F,F)-F 5% 3-HBB(F,F)-F 5% 5-HBB(F,F)-F 5% 3-HHBB(F,F)-F 3% 3-HH2BB(F,F)-F 3% The above composition had the following characteristics: T NI =61.8° C. T c <−20 C. η=23.6 mPa·s Δn=0.083 Vth=1.50 V VHR(25)=98.7% VHR(100)=95.6% τ=40 ms This composition had low viscosity, but small Δn, high threshold voltage and low T NI .", "Comparative Example 7 The composition (Example 37) with the largest Δn of the compositions disclosed in WO 96/11897 was prepared in the following manner.", "3-HBCF2OB(F,F)-F 5% 3-HBCF2OB-OCF3 5% 3-HB-CL 4% 5-HB-CL 4% 7-HB-CL 5% 2-HHB-CL 6% 3-HHB-CL 7% 5-HHB-CL 6% 2-HBB(F)-F 6% 3-HBB(F)-F 6% 5-HBB(F)-F 12% 3-HBB(F,F)-F 13% 5-HBB(F,F)-F 13% 3-H2HB(F)-CL 3% 3-HB(F)TB-2 3% 3-HB(F)VB-2 2% The above composition had the following characteristics: T NI =89.3° C. T c <−20° C. η=21.9 mPa·s Δn=0.128 Vth=2.08 V VHR(25)=98.4% VHR(100)=93.5% τ=30 ms This composition had low viscosity and large Δn, but high threshold voltage and somewhat low VHR at high temperatures.", "EXAMPLE 1 The following liquid crystal composition was prepared.", "First Component 2-HB(F,F)CF2OB(F,F)-F 15% 3-HB(F,F)CF2OB(F,F)-F 15% 4-HB(F,F)CF2OB(F,F)-F 15% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HBB(F,F)-F 10% 2-HHBB(F,F)-F 5% 3-HHBB(F,F)-F 5% 4-HHBB(F,F)-F 5% 5-HHBB(F,F)-F 5% 3-HH2BB(F,F)-F 5% The above composition had the following characteristics: T NI =84.2° C. T c <−20° C. η=44.0 mPa·s Δn=0.106 Vth=1.04 V VHR(25)=98.7% VHR(100)=95.1% τ=57 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 2 The following liquid crystal composition was prepared.", "First Component 3-HB(F,F)CF2OB(F,F)-F 6% 5-HB(F,F)CF2OB(F,F)-F 5% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HHB(F,F)-F 5% 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)-F 19% 5-HBB(F,F)-F 19% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 4-HHBB(F,F)-F 3% The above composition had the following characteristics: T NI =80.6° C. T c <−30° C. τ=39.0 mPa·s Δn=0.110 Vth=1.20 V VHR(25)=98.7% VHR(100)=95.8% τ=40 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 3 The following liquid crystal composition was prepared.", "First Component 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% 2-HH2B(F,F)CF2OB(F,F)-F 4% 3-HH2B(F,F)CF2OB(F,F)-F 4% Second Component 3-HBB(F,F)-F 27% 5-HBB(F,F)-F 27% 3-H2BB(F,F)-F 5% 5-H2BB(F,F)-F 5% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% The above composition had the following characteristics: T NI =77.1° C. T c <−20° C. η=44.0 mPa·s Δn=0.123 Vth=1.19 V VHR(25)=98.7% VHR(100)=96.2% τ=45 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 4 The following liquid crystal composition was prepared.", "First Component 3-HB(F,F)CF2OB(F)-OCF3 4% 4-HB(F,F)CF2OB(F)-OCF3 4% 5-HB(F,F)CF2OB(F)-OCF3 3% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HH2B(F,F)-F 5% 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)-F 19% 5-HBB(F,F)-F 19% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 4-HHBB(F,F)-F 3% The above composition had the following characteristics: T NI =84.0° C. T c <−30° C. η=38.0 mPa·s Δn=0.112 Vth=1.23 V VHR(25)=98.7% VHR(100)=96.0% τ=38 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 5 The following liquid crystal composition was prepared.", "First Component 2-HHB(F,F)CF2OB(F)-F 5% 3-HHB(F,F)CF2OB(F)-F 5% 2-HHB(F,F)CF2OB(F)-OCF3 5% 3-HHB(F,F)CF2OB(F)-OCF3 5% 2-HHB(F,F)CF2OB(F,F)-F 4% 3-HHB(F,F)CF2OB(F,F)-F 4% Second Component 3-HBB(F,F)-F 27% 5-HBB(F,F)-F 27% 3-H2BB(F,F)-F 5% 5-H2BB(F,F)-F 5% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% The above composition had the following characteristics: T NI =79.3° C. T c <−20° C. η=42.0 mPa·s Δn=0.125 Vth=1.20 V VHR(25)=98.7% VHR(100)=95.5% τ=42 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 6 The following liquid crystal composition was prepared.", "First Component 3-HB(F,F)CF2OB(F)-F 3% 3-HB(F,F)CF2OB(F)-OCF2H 2% 3-HB(F,F)CF2OB(F,F)-OCF3 2% 3-H2B(F,F)CF2OB(F,F)-F 2% 3-HB(F,F)CF2OB(F,F)-OCF2H 2% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component 3-HH2B(F,F)-F 5% 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)-F 19% 5-HBB(F,F)-F 19% 2-HHBB(F,F)-F 4% 3-HHBB(F,F)-F 4% 4-HHBB(F,F)-F 3% The above composition had the following characteristics: T NI =85.3° C. T c <−20° C. η=38.5 mPa·s Δn=0.120 Vth=1.21 V VHR(25)=98.5% VHR(100)=95.9% τ=36 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 7 The following liquid crystal composition was prepared.", "First Component 2-H2B(F,F)CF2OB(F)-F 2% 3-H2B(F,F)CF2OB(F)-OCF3 2% 2-H2B(F,F)CF2OB(F,F)-OCF3 2% 2-HB(F,F)CF2OB(F,F)-F 10% 3-HB(F,F)CF2OB(F,F)-F 14% 4-HB(F,F)CF2OB(F,F)-F 15% 2-HHB(F,F)CF2OB(F)-OCF2H 2% 3-HHB(F,F)CF2OB(F,F)OCF3 2% 2-HHB(F,F)CF2OB(F,F)-F 4% 3-HHB(F,F)CF2OB(F,F)-F 4% 4-HHB(F,F)CF2OB(F,F)-F 4% 5-HHB(F,F)CF2OB(F,F)-F 4% Second Component 3-HBB(F,F)-F 10% 2-HHBB(F,F)-F 5% 3-HHBB(F,F)-F 5% 4-HHBB(F,F)-F 5% 5-HHBB(F,F)-F 5% 3-HH2BB(F,F)-F 5% The above composition had the following characteristics: T NI =85.0° C. T c <−20° C. η=41.0 mPa·s Δn=0.110 Vth=1.12 V VHR(25)=98.7% VHR(100)=95.3% τ=52 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 8 The following liquid crystal composition was prepared.", "First Component: 2-HB(F,F)CF2OB(F,F)-F 15% 3-HB(F,F)CF2OB(F,F)-F 15% 4-HB(F,F)CF2OB(F,F)-F 15% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component: 3-HBB(F,F)-F 10% 2-HHBB(F,F)-F 5% 3-HHBB(F,F)-F 5% 4-HHBB(F,F)-F 5% 5-HHBB(F,F)-F 5% Third Component: 5-HBB(F)B-2 5% The above composition had the following characteristics: T NI =84.2° C. T c <−20° C. η=43.6 mPa·s Δn=0.111 Vth=1.12 V VHR(25)=98.7% VHR(100)=96.1% τ=49 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "EXAMPLE 9 The following liquid crystal composition was prepared.", "First Component: 3-HB(F,F)CF2OB(F,F)-F 6% 5-HB(F,F)CF2OB(F,F)-F 5% 2-HHB(F,F)CF2OB(F,F)-F 5% 3-HHB(F,F)CF2OB(F,F)-F 5% 4-HHB(F,F)CF2OB(F,F)-F 5% 5-HHB(F,F)CF2OB(F,F)-F 5% Second Component: 3-HHB(F,F)-F 3-H2HB(F,F)-F 5% 4-H2HB(F,F)-F 5% 5-H2HB(F,F)-F 5% 3-HBB(F,F)F 19% 5-HBB(F,F)-F 19% Third Component: 5-HBB(F)B-2 6% 5-HBB(F)B-3 5% The above composition had the following characteristics: T NI =80.6° C. T c <−20° C. η=36.8 mPa·s Δn=0.121 Vth=1.26 V VHR(25)=98.7% VHR(100)=95.6% τ=39 ms This composition had high VHR at high temperatures, small Vth, large Δn and fast τ.", "As shown in the above Examples, the present invention can provide the liquid crystal compositions for AM-LCD, especially having high voltage holding ratio at high temperatures, sufficiently low threshold voltage and large optical anisotropy, while satisfying general characteristics required for the AM-CD display mode." ]
CROSS-REFERENCES None. FIELD OF THE INVENTION This invention relates generally to electrical/electronic controls, and particularly concerns a control mounting and wiring framework system for use in the installation and operation of various electrical/electronic control devices. BACKGROUND OF THE INVENTION Numerous different known equipment framework constructions and installation procedures have been proposed in with electrical/electronic system control arrangements. For instance, U.S. Pat. No. 2,140,376 issued to Anderson discloses a panel board construction wherein a network of wireways is joined to the reverse side of a panel board to which and through which various electrical/electronic devices are mounted and wired. U.S. Pat. No. 2,572,617 granted to Haury, et al. discloses a continuous front electrical panel having panel front segments which may be selectively tilted down to give maintenance rear access to mounted electrical/electronic devices. No disclosure is made of incorporated wireways or of conductor classification and segregation. U.S. Pat. No. 3,321,672 issued in the names of Kuhn, et al. discloses a system of side-by-side modular control panels with means for integrating multiple panels into a unitary system but in each instance the completed system presents a continuous front making access to the wiring of individual devices more inconvenient than necessary. U.S. Pat. No. 4,700,846 issued to Schroder relates to the mounting of printed circuit boards on an instrument rack and while giving excellent wiring access to installed individual devices does not provide wire trays which may readily be assembled to give a capability for conductor classification and segregation. U.S. Pat. No. 5,046,172 granted to Moreux, et al. teaches a power distribution bus system housed in a covered and insulated trough or tray and means for connecting particular devices to the bus system through cover openings and the use of translational plugging/unplugging device movement. U.S. Pat. No. 5,326,934 granted to LeMaster, et al. teaches a system which has multiple control panel cabinets that satisfy the diverse wiring needs of an environment having numerous workstations. The system primarily transforms workstation individual cabling requirements into workstation collective cabling to reduce material, installation, and revision costs of multiple workstation connectivity. See also the article "Wiring System Offers a Back Panel Alternative" by Udo Lutze in the July/August 1994 issue of Electrical Design and Manufacturing for details of a still different approach to the construction and wiring of an electrical/electronic system control arrangement. One of the principal objects of this invention is to provide a simplified and modular form of framework for mounting and incorporating numerous of different control devices such as circuit breakers, terminal blocks, relays, and the like into a control system. Another principal object of this invention is to provide a control system framework which readily may be constructed to permit the segregation of wiring connections to, from, and between the mounted electrical/electronic control devices into trays or channels of different voltage or frequency classes. A still further object of the present invention is to in most cases eliminate the need for on-site drilling and tapping of connector features in order to accomplish control system installation. Another object of this invention is to provide a control system construction with improved air circulation and heat dissipation capabilities, particularly as the control system is installed within a cabinet-type enclosure. Still other objects and advantages of the present invention will become apparent during a consideration of the invention summary, drawings, detailed description, and claims which follow. SUMMARY OF THE INVENTION The present invention is an electrical/electronic control system support framework which basically is comprised of multiple, spaced-apart vertical tray members that have a preferred extrusion cross-section configuration, of multiple, spaced-apart horizontal tray members that have a preferred extrusion cross-section configuration with a control device support feature and that are supported by the vertical tray members, and of removable fasteners which join the horizontal tray members to the vertical tray members. The framework system fastener elements cooperate with modular and uniformly spaced-apart fastener receptacle features provided in the horizontal tray members and in the cooperating vertical tray members. Various accessory devices, including wiring management comb devices, snap-on tray covers, and terminal block angled mounting brackets, may be combined with the framework to further enhance its utility. DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation view of a preferred embodiment of the framework system of the present invention; FIG. 2 is a sectional view as taken along any of lines 2--2 of FIG. 1; FIG. 2A is a sectional view of an alternate embodiment of the fastener device depicted in FIG. 2; FIG. 3 is a sectional view as taken along any of lines 3--3 of FIG. 1; FIG. 4 is a perspective view of a portion of a typical snap-on cover accessory that may be advantageously utilized with the framework system of FIG. 1; FIG. 5 is a perspective view of an angled adaptor accessory that may be advantageously utilized with the framework system of FIG. 1 for the subsequent installation of electrical devices having DIN-type rail mounts; FIG. 6 is a perspective view of a straight adaptor accessory that may advantageously be utilized with the framework system of FIG. 1 for the subsequent installation of electrical devices having NEMA-type rail mounts; and FIG. 7 is a perspective view of a portion of the framework system of FIG. 1 illustrating the manner of mounting a representative electrical/electronic control device on a horizontal tray member and of routing the control wires for the device in the horizontal tray member and in an adjacent vertical tray member. DETAILED DESCRIPTION A preferred and representative embodiment of the framework system of this invention is referenced generally by the numeral 10 in FIG. 1 and is basically comprised of two, three or more spaced-apart vertical tray members 12 and of three or more, as required, spaced-apart horizontal tray member 14 joined to and supported by vertical tray members 12 through co-operating fastener devices 16. As elsewhere detailed in the drawings, each fastener device 16 is preferably a flat-head threaded screw and nut combination that cooperates with one of numerous uniformly spaced-apart pre-drilled fastener holes provided in each of horizontal tray members 14 and with a slotted opening and fastener recess feature provided by extrusion in each of vertical tray members 12. Vertical tray members 12 in a typical or representative system 10 installation are normally anchored to co-operating top and bottom structural elements such as the inside back wall of standard commercial electrical enclosures (boxes) which are manufactured for safe containment of electrical controls (illustrated only by phantom lines in FIG. 1) by threaded fastener devices similar to fastener element 16. It should be noted that vertical tray members 12 may have a serrated V-groove 13 which accepts a self-tapping screw or fastener device 16' as depicted in FIG. 2A in place of the threaded screw and nut combination shown in FIG. 2. FIG. 2 illustrates the cross-sectional configuration of one form of vertical tray member 12 satisfactory for the practice of this invention utilizing the threaded screw and nut combination referred to above. Tray member 12 is preferably an aluminum extrusion pre-cut to proper length prior to installation in system 10, and has a generally U-shaped cross-sectional configuration. The U-shaped configuration is derived from the illustrated arrangement of integrated rear wall section 20, side wall sections 22, 24, 26, and 28, and web sections 30 and 32. The U-shaped extrusion cross-section configuration of FIG. 2 is also provided with elongated and continuous slots or gaps 34 and 36 through which the stem of a fastener device 16 may be passed. In the FIG. 2 arrangement the wire-carrying zone of member 12 is located within wall sections 20, 24, and 26, and the fastener-receiving or enclosure zones are bounded by wall sections 22 and 24, web section 30, and a pair of slots 34 and 36 at one lateral extreme and by wall sections 26 and 28, web section 32, and a pair of slots 34 and 36 at the opposite lateral extreme. In one actual embodiment of this invention the overall dimensions of the vertical tray member extrusion are approximately 50 millimeters by 110 millimeters. It is also preferred that the center-to-center distance between the pair of slots 34 and also between the pair of slots 36 be a nominal 100 millimeters which is a multiple of a nominal 25 millimeter spacing basis between adjacent fastener openings provided in horizontal tray members 14 thus giving system 10 an increased capability for varying the placement and horizontal spacing between vertical members 12. Also it should be noted that the lateral spacings in the vertical tray member 12 extrusion depicted in FIG. 2 between wall sections 22 and 24 and between wall sections 26 and 28 are controlled so as to permit receiving the nut portion of a fastener device 16 yet preventing rotation of that nut portion during rotation of the threaded fastener stem. In the embodiment depicted in FIG. 2A, the wire-carrying zone of member 12 located within wall sections 20, 24, and 26. This is the same as the wire-carrying zone of the preferred embodiment of FIG. 2. However, in the alternate embodiment of vertical tray 12 illustrated in FIG. 2A the fastener receiving or enclosure zones 15 and 17 are located outboard of wall section 24 and 26 and are formed with V-shaped serrated grooves 13 formed in an extruded wall 19. The grooves 13 are adapted to receive a self tapping fastener device 16'. The serrated groove 13 and self tapping fastener 16' of this embodiment has an advantage in that a one piece fastener 16' may be utilized in place of a two piece nut and bolt fastener 16. As best shown in FIG. 3, the extrusion comprising horizontal tray member 14 has a basic H-shaped configuration. Horizontal tray member 14 is comprised of integrated front wall section 40, rear wall section 42, and intermediate, spaced-apart web sections 44 and 46. Also included in the cross-section configuration of FIG. 3 are integrally-formed right-angle flanges 48 and 50 which are properly located and sized to comprise a DIN (Deutsche Industrie Norm)-type mounting rail for co-operably supporting various electrical/electronic control devices. Alternatively, integral right-angle flanges arranged to comprise a NEMA (National Electrical Manufacturers Association)-type mounting rail may be used in place of the DIN-type mounting rail. As discussed in connection with FIG. 6, an adaptor device may be combined with the DIN-type mounting rail configuration to convert it to the NEMA-type mounting rail configuration. The intermediate integral web sections 44 and 46 are essentially centrally positioned and are spaced apart a sufficient distance to provide a fastener device accommodation zone that is essentially defined as being interiorly of extrusion wall and web sections 40, 42, 44, and 46. The extrusion cross-section open zones defined by front wall section 40, rear wall section 42, and upper web section 44, and by front wall section 40, rear wall section 42, and lower web section 46 constitute the extrusion wire-carrying trays. As previously indicated, I prefer that fastener devices 16 utilized in the construction of system 10 be flat-head machine screw and nut combinations. Accordingly, the central section of front wall section 40 of the tray member 14 extrusion is provided with a V-groove feature to accommodate the conical head of a flat-headed machine screw. Also, although not illustrated in FIG. 3 (see FIG. 1 instead), each horizontal tray member 14 extrusion is subsequently provided with multiple, oppositely-aligned and drilled openings (holes) in wall sections 40 and 42 to accommodate the ready installation of fastener devices 16 into system 10. As previously indicated, such oppositely aligned fastener device openings are preferably separated by 25 millimeter spacings. FIG. 4 illustrates an extruded (and preferably yieldable plastic) snap-on cover member 60 which may be advantageously utilized in instances wherein it is desired to cover major portions of those system 10 tray member wireways which carry various electrical/electronic control device wires to and from different points of connection or utilization. The protruding underside integral flanges 62 are spaced apart so that their enlarged terminations 63 have a slight interference fit with the enlarged wall terminations 45 of wall sections 40 and 42. In FIG. 5 I illustrate an adaptor accessory 70 for system 10 that may be utilized in instances wherein it is desired to have the DIN-type mounting rail element comprised of combined flanges 48 and 50 mounted at an angle such as 45° relative to true vertical. Adaptor 70 also is preferably fabricated of metal (e.g., aluminum) and may be formed by extrusion. The adaptor flanges designated 72 and 74 are sized and spaced apart so as to be slidably engaged with integral flanges 48 and 50 of horizontal tray member 14. Integrally formed right-angle flanges 76 and 78 essentially are sized and spaced-apart identically to mounting rail flanges 48 and 50. In FIG. 6 I illustrate an adaptor accessory 80 for system 10 that may be utilized in instances wherein it is desired to have the DIN-type mounting rail comprised of flanges 48 and 50 replaced by a NEMA-type mounting rail to take a threaded fastener connection. In adaptor 80, which also is preferably an aluminum extrusion, integral right-angle flanges 82 and 84 are also sized and spaced apart so as to be slidably engaged with integral flanges 48 and 50 of tray member 14. The illustrated longitudinal slot 86 of adaptor 80 functions to receive the stem of a threaded fastener with the fastener nut portion being rotationally restrained within the enclosed zone defined by the integral U-shaped enclosure wall section designated 88. FIG. 7 is provided in the drawings to illustrate the manner in which various wires may be routed to and from schematic electrical/electronic control devices 90 and 92 which are shown mounted on horizontal tray member 14 having a DIN-type device mounting rail. Depending upon the requirements of a particular installation of framework 10, wires running to or from the system control devices may be looped either upwardly or downwardly and into the upper or lower wireway of tray member 14. The so-routed wires may then be run laterally within the wireway interior zones to an appropriate one of vertical tray members 12 where it is subsequently routed in the vertical tray member wireway upwardly or downwardly to another horizontal tray member or to a source connection. Depending upon the number of different voltage, frequency, or interference resistance classifications that may pertain to the overall control system, individual vertical tray members and horizontal tray member wireway zones may be dedicated or segregated to include wires only in a particular wireway classification. One of the major advantages associated with the above-described modular control framework system is the high degree of structural rigidity that is developed using the illustrated construction of vertical tray members, horizontal tray members supported by the vertical tray members, and mechanical fasteners. Other component materials, component shapes, and component sizes may be utilized in the practice of the present invention without departing from the scope or intent of the claims which follow.
A framework system for supporting multiple electrical/electronic control devices and for use in routing wires extending to and from the control devices is comprised of multiple, spaced-apart vertical tray members having an included vertically-extending wireway zone, multiple, spaced-apart horizontal tray members having included horizontally-extending wireway zones, and fastener means rigidly joining said spaced-apart horizontal tray members to said spaced-apart vertical tray members.
Summarize the key points of the given document.
[ "CROSS-REFERENCES None.", "FIELD OF THE INVENTION This invention relates generally to electrical/electronic controls, and particularly concerns a control mounting and wiring framework system for use in the installation and operation of various electrical/electronic control devices.", "BACKGROUND OF THE INVENTION Numerous different known equipment framework constructions and installation procedures have been proposed in with electrical/electronic system control arrangements.", "For instance, U.S. Pat. No. 2,140,376 issued to Anderson discloses a panel board construction wherein a network of wireways is joined to the reverse side of a panel board to which and through which various electrical/electronic devices are mounted and wired.", "U.S. Pat. No. 2,572,617 granted to Haury, et al.", "discloses a continuous front electrical panel having panel front segments which may be selectively tilted down to give maintenance rear access to mounted electrical/electronic devices.", "No disclosure is made of incorporated wireways or of conductor classification and segregation.", "U.S. Pat. No. 3,321,672 issued in the names of Kuhn, et al.", "discloses a system of side-by-side modular control panels with means for integrating multiple panels into a unitary system but in each instance the completed system presents a continuous front making access to the wiring of individual devices more inconvenient than necessary.", "U.S. Pat. No. 4,700,846 issued to Schroder relates to the mounting of printed circuit boards on an instrument rack and while giving excellent wiring access to installed individual devices does not provide wire trays which may readily be assembled to give a capability for conductor classification and segregation.", "U.S. Pat. No. 5,046,172 granted to Moreux, et al.", "teaches a power distribution bus system housed in a covered and insulated trough or tray and means for connecting particular devices to the bus system through cover openings and the use of translational plugging/unplugging device movement.", "U.S. Pat. No. 5,326,934 granted to LeMaster, et al.", "teaches a system which has multiple control panel cabinets that satisfy the diverse wiring needs of an environment having numerous workstations.", "The system primarily transforms workstation individual cabling requirements into workstation collective cabling to reduce material, installation, and revision costs of multiple workstation connectivity.", "See also the article "Wiring System Offers a Back Panel Alternative"", "by Udo Lutze in the July/August 1994 issue of Electrical Design and Manufacturing for details of a still different approach to the construction and wiring of an electrical/electronic system control arrangement.", "One of the principal objects of this invention is to provide a simplified and modular form of framework for mounting and incorporating numerous of different control devices such as circuit breakers, terminal blocks, relays, and the like into a control system.", "Another principal object of this invention is to provide a control system framework which readily may be constructed to permit the segregation of wiring connections to, from, and between the mounted electrical/electronic control devices into trays or channels of different voltage or frequency classes.", "A still further object of the present invention is to in most cases eliminate the need for on-site drilling and tapping of connector features in order to accomplish control system installation.", "Another object of this invention is to provide a control system construction with improved air circulation and heat dissipation capabilities, particularly as the control system is installed within a cabinet-type enclosure.", "Still other objects and advantages of the present invention will become apparent during a consideration of the invention summary, drawings, detailed description, and claims which follow.", "SUMMARY OF THE INVENTION The present invention is an electrical/electronic control system support framework which basically is comprised of multiple, spaced-apart vertical tray members that have a preferred extrusion cross-section configuration, of multiple, spaced-apart horizontal tray members that have a preferred extrusion cross-section configuration with a control device support feature and that are supported by the vertical tray members, and of removable fasteners which join the horizontal tray members to the vertical tray members.", "The framework system fastener elements cooperate with modular and uniformly spaced-apart fastener receptacle features provided in the horizontal tray members and in the cooperating vertical tray members.", "Various accessory devices, including wiring management comb devices, snap-on tray covers, and terminal block angled mounting brackets, may be combined with the framework to further enhance its utility.", "DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation view of a preferred embodiment of the framework system of the present invention;", "FIG. 2 is a sectional view as taken along any of lines 2--2 of FIG. 1;", "FIG. 2A is a sectional view of an alternate embodiment of the fastener device depicted in FIG. 2;", "FIG. 3 is a sectional view as taken along any of lines 3--3 of FIG. 1;", "FIG. 4 is a perspective view of a portion of a typical snap-on cover accessory that may be advantageously utilized with the framework system of FIG. 1;", "FIG. 5 is a perspective view of an angled adaptor accessory that may be advantageously utilized with the framework system of FIG. 1 for the subsequent installation of electrical devices having DIN-type rail mounts;", "FIG. 6 is a perspective view of a straight adaptor accessory that may advantageously be utilized with the framework system of FIG. 1 for the subsequent installation of electrical devices having NEMA-type rail mounts;", "and FIG. 7 is a perspective view of a portion of the framework system of FIG. 1 illustrating the manner of mounting a representative electrical/electronic control device on a horizontal tray member and of routing the control wires for the device in the horizontal tray member and in an adjacent vertical tray member.", "DETAILED DESCRIPTION A preferred and representative embodiment of the framework system of this invention is referenced generally by the numeral 10 in FIG. 1 and is basically comprised of two, three or more spaced-apart vertical tray members 12 and of three or more, as required, spaced-apart horizontal tray member 14 joined to and supported by vertical tray members 12 through co-operating fastener devices 16.", "As elsewhere detailed in the drawings, each fastener device 16 is preferably a flat-head threaded screw and nut combination that cooperates with one of numerous uniformly spaced-apart pre-drilled fastener holes provided in each of horizontal tray members 14 and with a slotted opening and fastener recess feature provided by extrusion in each of vertical tray members 12.", "Vertical tray members 12 in a typical or representative system 10 installation are normally anchored to co-operating top and bottom structural elements such as the inside back wall of standard commercial electrical enclosures (boxes) which are manufactured for safe containment of electrical controls (illustrated only by phantom lines in FIG. 1) by threaded fastener devices similar to fastener element 16.", "It should be noted that vertical tray members 12 may have a serrated V-groove 13 which accepts a self-tapping screw or fastener device 16'", "as depicted in FIG. 2A in place of the threaded screw and nut combination shown in FIG. 2. FIG. 2 illustrates the cross-sectional configuration of one form of vertical tray member 12 satisfactory for the practice of this invention utilizing the threaded screw and nut combination referred to above.", "Tray member 12 is preferably an aluminum extrusion pre-cut to proper length prior to installation in system 10, and has a generally U-shaped cross-sectional configuration.", "The U-shaped configuration is derived from the illustrated arrangement of integrated rear wall section 20, side wall sections 22, 24, 26, and 28, and web sections 30 and 32.", "The U-shaped extrusion cross-section configuration of FIG. 2 is also provided with elongated and continuous slots or gaps 34 and 36 through which the stem of a fastener device 16 may be passed.", "In the FIG. 2 arrangement the wire-carrying zone of member 12 is located within wall sections 20, 24, and 26, and the fastener-receiving or enclosure zones are bounded by wall sections 22 and 24, web section 30, and a pair of slots 34 and 36 at one lateral extreme and by wall sections 26 and 28, web section 32, and a pair of slots 34 and 36 at the opposite lateral extreme.", "In one actual embodiment of this invention the overall dimensions of the vertical tray member extrusion are approximately 50 millimeters by 110 millimeters.", "It is also preferred that the center-to-center distance between the pair of slots 34 and also between the pair of slots 36 be a nominal 100 millimeters which is a multiple of a nominal 25 millimeter spacing basis between adjacent fastener openings provided in horizontal tray members 14 thus giving system 10 an increased capability for varying the placement and horizontal spacing between vertical members 12.", "Also it should be noted that the lateral spacings in the vertical tray member 12 extrusion depicted in FIG. 2 between wall sections 22 and 24 and between wall sections 26 and 28 are controlled so as to permit receiving the nut portion of a fastener device 16 yet preventing rotation of that nut portion during rotation of the threaded fastener stem.", "In the embodiment depicted in FIG. 2A, the wire-carrying zone of member 12 located within wall sections 20, 24, and 26.", "This is the same as the wire-carrying zone of the preferred embodiment of FIG. 2. However, in the alternate embodiment of vertical tray 12 illustrated in FIG. 2A the fastener receiving or enclosure zones 15 and 17 are located outboard of wall section 24 and 26 and are formed with V-shaped serrated grooves 13 formed in an extruded wall 19.", "The grooves 13 are adapted to receive a self tapping fastener device 16'.", "The serrated groove 13 and self tapping fastener 16'", "of this embodiment has an advantage in that a one piece fastener 16'", "may be utilized in place of a two piece nut and bolt fastener 16.", "As best shown in FIG. 3, the extrusion comprising horizontal tray member 14 has a basic H-shaped configuration.", "Horizontal tray member 14 is comprised of integrated front wall section 40, rear wall section 42, and intermediate, spaced-apart web sections 44 and 46.", "Also included in the cross-section configuration of FIG. 3 are integrally-formed right-angle flanges 48 and 50 which are properly located and sized to comprise a DIN (Deutsche Industrie Norm)-type mounting rail for co-operably supporting various electrical/electronic control devices.", "Alternatively, integral right-angle flanges arranged to comprise a NEMA (National Electrical Manufacturers Association)-type mounting rail may be used in place of the DIN-type mounting rail.", "As discussed in connection with FIG. 6, an adaptor device may be combined with the DIN-type mounting rail configuration to convert it to the NEMA-type mounting rail configuration.", "The intermediate integral web sections 44 and 46 are essentially centrally positioned and are spaced apart a sufficient distance to provide a fastener device accommodation zone that is essentially defined as being interiorly of extrusion wall and web sections 40, 42, 44, and 46.", "The extrusion cross-section open zones defined by front wall section 40, rear wall section 42, and upper web section 44, and by front wall section 40, rear wall section 42, and lower web section 46 constitute the extrusion wire-carrying trays.", "As previously indicated, I prefer that fastener devices 16 utilized in the construction of system 10 be flat-head machine screw and nut combinations.", "Accordingly, the central section of front wall section 40 of the tray member 14 extrusion is provided with a V-groove feature to accommodate the conical head of a flat-headed machine screw.", "Also, although not illustrated in FIG. 3 (see FIG. 1 instead), each horizontal tray member 14 extrusion is subsequently provided with multiple, oppositely-aligned and drilled openings (holes) in wall sections 40 and 42 to accommodate the ready installation of fastener devices 16 into system 10.", "As previously indicated, such oppositely aligned fastener device openings are preferably separated by 25 millimeter spacings.", "FIG. 4 illustrates an extruded (and preferably yieldable plastic) snap-on cover member 60 which may be advantageously utilized in instances wherein it is desired to cover major portions of those system 10 tray member wireways which carry various electrical/electronic control device wires to and from different points of connection or utilization.", "The protruding underside integral flanges 62 are spaced apart so that their enlarged terminations 63 have a slight interference fit with the enlarged wall terminations 45 of wall sections 40 and 42.", "In FIG. 5 I illustrate an adaptor accessory 70 for system 10 that may be utilized in instances wherein it is desired to have the DIN-type mounting rail element comprised of combined flanges 48 and 50 mounted at an angle such as 45° relative to true vertical.", "Adaptor 70 also is preferably fabricated of metal (e.g., aluminum) and may be formed by extrusion.", "The adaptor flanges designated 72 and 74 are sized and spaced apart so as to be slidably engaged with integral flanges 48 and 50 of horizontal tray member 14.", "Integrally formed right-angle flanges 76 and 78 essentially are sized and spaced-apart identically to mounting rail flanges 48 and 50.", "In FIG. 6 I illustrate an adaptor accessory 80 for system 10 that may be utilized in instances wherein it is desired to have the DIN-type mounting rail comprised of flanges 48 and 50 replaced by a NEMA-type mounting rail to take a threaded fastener connection.", "In adaptor 80, which also is preferably an aluminum extrusion, integral right-angle flanges 82 and 84 are also sized and spaced apart so as to be slidably engaged with integral flanges 48 and 50 of tray member 14.", "The illustrated longitudinal slot 86 of adaptor 80 functions to receive the stem of a threaded fastener with the fastener nut portion being rotationally restrained within the enclosed zone defined by the integral U-shaped enclosure wall section designated 88.", "FIG. 7 is provided in the drawings to illustrate the manner in which various wires may be routed to and from schematic electrical/electronic control devices 90 and 92 which are shown mounted on horizontal tray member 14 having a DIN-type device mounting rail.", "Depending upon the requirements of a particular installation of framework 10, wires running to or from the system control devices may be looped either upwardly or downwardly and into the upper or lower wireway of tray member 14.", "The so-routed wires may then be run laterally within the wireway interior zones to an appropriate one of vertical tray members 12 where it is subsequently routed in the vertical tray member wireway upwardly or downwardly to another horizontal tray member or to a source connection.", "Depending upon the number of different voltage, frequency, or interference resistance classifications that may pertain to the overall control system, individual vertical tray members and horizontal tray member wireway zones may be dedicated or segregated to include wires only in a particular wireway classification.", "One of the major advantages associated with the above-described modular control framework system is the high degree of structural rigidity that is developed using the illustrated construction of vertical tray members, horizontal tray members supported by the vertical tray members, and mechanical fasteners.", "Other component materials, component shapes, and component sizes may be utilized in the practice of the present invention without departing from the scope or intent of the claims which follow." ]
This application is a continuation of Ser. No. 09/111,460 filed Jul. 7, 1998. DETAILED DESCRIPTION OF THE INVENTION 1. Field of the Invention This invention relates to a magnetic record reproducing apparatus, and more particularly, to a video tape recorder and a television with a video tape recorder to it. 2. Prior Art In the conventional magnetic record reproducing apparatus, and more particularly, a video tape recorder, a power circuit, and a circuit except for it, namely, a video circuit were engaged in another print wiring substrate, and were positioned at a distance to avoid the influences of electric noises and magnetic fields and heat of the power pulse transfer. PROBLEMS TO BE SOLVED BY THE INVENTION A shield plate was required to be covered on the power circuit, because the power circuit and the video circuit were hard to avoid the influences of the magnetic field of the pulse transfer for power use in the space limited even if they were positioned at some distance. Between the print wiring substrate engaged with the power circuit and the print wiring substrate with the video circuit being engaged with it were required many connecting wirings, whereby the operationally was worse and further electric noises were easy to be provided in these wirings. An object of this invention is to provide a magnetic record reproducing apparatus having a configuration aimed at reducing the cost. MEANS FOR SOLVING THE PROBLEMS In the magnetic record reproducing apparatus of this invention, the power circuit is provided with a transfer having a core with a gap being formed init, and the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux from the gap of the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer is positioned with such a length being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux. Thus, the magnetic flux leaking from the transfer hardly comes out in the direction of the magnetic head. Since the cylinder where the magnetic head is provided and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux. In the magnetic record reproducing apparatus of this invention, the electronic parts of the power circuit is engaged with a power region which is one region in one print wiring substrate, the electronic parts for the record reproducing use, having a magnetic head except for the electronic parts of the power circuit, is provided with the print wiring substrate mounted in the record reproducing circuit region which is a region except for the power region of the print wiring substrate Also, the power circuit of the power region is provided with a transfer having a core with a gap being formed in it, the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux the gap of the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided, with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux. In this case the magnetic flux leak from the transfer hardly comes out in the direction of the magnetic head. Since the cylinder where the magnetic head is provided and the transfer is positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux. The electronic parts of the power circuit, and the record reproducing electronic parts such as a magnetic head except for the electronic parts of the power circuit are positioned an one print wiring substrate by the positioning in different region on the print wiring substrate. In a magnetic record reproducing apparatus of this invention, the above description can be conducted even if the transfer is large in relatively leakage magnetic flux as in the pulse transfer. The magnetic record reproducing apparatus is to include the magnetic reproducing specific apparatus. PREFERRED EMBODIMENT OF THE INVENTION The embodiment of the magnetic record reproducing apparatus of this invention will be described with reference to FIG. 1 through FIG. 3 . FIG. 1 is a schematic plan view showing the positional relation between the print wiring substrate in the magnetic record reproducing apparatus of this invention, the head on the cylinder and the pulse transfer, and the condition or the leakage magnetic flux of the pulse transfer. FIG. 2 is a schematic side view of a pulse transfer in the magnetic record reproducing apparatus of this invention. FIG. 3 is a plan view showing the core portion of the pulse transfer. As shown in FIG. 1, the magnetic record reproducing apparatus of this invention is comprised of a print wiring substrate 100 , a video mechanism parts mounting chassis 200 mounted in the upper portion of the print wiring substrate 100 , a cylinder 300 positioned on the video mechanism parts mounting chassis 200 , and a pulse transfer 400 of the power circuit positioned in the upper portion of the print wiring substrate 100 , and in a region where the video mechanism parts mounting chassis 200 is not mounted. The print wiring substrate 100 is comprised of a power region 110 , a record regenerating circuit region 120 except for the power region 110 . On the record reproducing circuit region 120 is engaged a main parts of record reproducing electronic parts not shown with a chassis 200 to cover the upper portion side of the main parts. In the cylinder 300 is provided with the magnetic head 310 . As shown in FIG. 2, the pulse transfer 400 is a split winding type, which is different by 90° from the normal split winding type in the coil winding direction, and is a type of being mounted with the normal split winding type laying horizontally. The pulse transfer 400 is comprised of a core portion 410 , a base winding 420 , primary windings 421 , 423 , a secondary winding 422 , and section walls 430 , 431 , 432 , 433 , 434 for separating these windings. As shown in FIG. 3, the core portion 410 is an E—E type ferrite core where E and E are combined with. The core portion 410 has a gap 410 a at its center. The respective lower end sides 430 a, 431 a, 432 a, 433 a , 434 a of the section walls 430 , 431 , 432 433 , 434 are inserted into the through hole portions not shown of the print wiring substrate 100 , thereby forming substrate terminal portions to be soldered and fixed. The substrate terminal portion 430 a is connected with one end portion 420 a of the base winding 420 , and the other end portion of the base winding 420 positioned on the inner side in FIG. 2 . The substrate terminal portion 431 a is connected with one end portion 421 a of the primary winding 421 , and with the other end portion of the primary winding 421 positioned on the inner side in FIG. 2 . The substrate terminal portion 432 a is NC. The substrate terminal portion 433 a is connected with an end portion 422 a of the secondary winding 422 , and with the other end portion of the secondary winding 422 positioned on the inner side in FIG. 2 . The substrate terminal 434 a is connected with one end portion 423 a of the primary winding 423 , and with the other end portion of the primary winding 423 positioned on the inner side in FIG. 2 . High frequency current flows to the pulse transfer 400 . Since it is an alternating field in the direction of the magnetic pole, in FIG. 2, the N pole becomes the left side when the S pole is on the right, while the S pole becomes left when the N pole is on the right side. Prom the gap 410 a of the core portion 410 is generated a leakage flux 450 (see FIG. 1) in accordance with the magnetic pole direction. The leakage magnetic flux 450 is generated in the longitudinal length in the direction of the magnetic pole. The pulse transfer 400 is positioned in the power region 110 of the printing wiring substrate 100 so that a direction for connecting the S pole and the N pole with the leakage magnetic flux 450 from the gap 410 a of the core 410 may become almost vertical to the direction for connecting the central portion of the cylinder 300 where the magnetic head 310 is provided and with the central portion of the gap 410 a of the core 410 . The power region 110 is provided in the farthest region from the cylinder 300 . The pulse transfer 400 should be preferable to be positioned near the center of the power region 110 , as shown in, for example, FIG. 1, to radiate heat to be caused when the high frequency current flows. In the magnetic record reproducing apparatus of this invention constructed as above, the pulse transfer 400 is positioned to the magnetic head 310 provided in the cylinder 300 so that the leakage magnetic flux 450 from the pulse transfer 400 may not affect. Since the magnetic record reproducing apparatus of this invention does not require a shield plate to be covered on the pulse transfer 400 , the cost can be made lower. The print wiring substrate 100 is one substrate comprised of a power region 110 and a record reproducing circuit 120 except for the power region 110 . As when two print wiring substrates or more are provided as before, a plurality of connecting wirings are not required to be provided between the print wiring substrate with the power circuit being embodied and the print wiring substrate with the video circuit being embodied. Unnecessary operating time which is required to perform the connecting wiring between the print wiring substrates can be saved. Further, since no connecting wiring is provided between the print wiring substrates, the circuit configuration is hard to have electric noises generated. The configuration of the pulse transfer 400 of such a configuration is not limited to the above description except for the positional relation (for example, shape of the core, number of the windings, positional relation among the windings) among the winding direction, and the terminal portion to be inserted into the print wiring substrate. The pulse transfer 400 can be replaced by a different type of transfer which has the same configuration as that in the direction of the leakage magnetic flux and performs the electrically same function. In the above description, the video recorder is described as a magnetic record reproducing apparatus of this invention. As described above even in the other magnetic record reproducing apparatus such as television with a video tape recorder to it, a tape recorder, the similar effects can be obtained when the magnetic head and the power transfer are provided. The description thereof is omitted. EFFECT OF THE INVENTION As described above, in the magnetic record reproducing apparatus of the claim 1 of this invention, the power circuit is provided with a transfer having a core with a gap being formed in it, and the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux from the gap at the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided, with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux. Thus, the magnetic flux leaked from the transfer hardly comes out in the direction of the magnetic head. Since the cylinder where the magnetic head is provided, and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux. Thus, a shield plate for covering the entire power circuit is not required as conventionally, thus reducing the cost. In the magnetic record reproducing apparatus of the claim 2 of this invention, an electronic parts of the power circuit is engaged with a power region which is one region of one print wiring substrate, the electronic parts for the record reproducing use, having a magnetic head except for the electronic parts of the power circuit, is provided with the print wiring substrate mounted in the record reproducing circuit region which is a region except for the power region of the print wiring substrate. Also, the power circuit of the power region is provided with a transfer having a core with a gap being formed in it, the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux from the gap of the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided, with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux. In this case, the magnetic flux leaked from the transfer hardly comes out in the direction of the magnetic head. Since the cylinder where the magnetic head is provided, and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux. Thus, the shield plate for covering the entire power circuit is not required as conventionally, thus reducing the cost. The electronic parts of the power circuit, and the record reproducing electronic parts such as magnetic head except for the electronic parts of the power circuit are positioned on one print wiring substrate by the positioning in different region on the print wiring substrate. Thus, many connecting wirings are not required to be provided between the print wiring substrate where the power circuit is engaged and the print wiring substrate where the video circuit is engaged, as divided in the conventional two print wiring substrates or more. Unnecessary operation time which was required to conduct the connecting wiring between the print wiring substrates can be saved. Thus, lower cost can be provided. Since no connecting wiring between the print wiring substrates is provided the electric noises are hard to be provided. In a magnetic record reproducing apparatus of the claim 3 of this invention, the above description can be conducted even if the transfer is large in relatively leakage magnetic flux as in the pulse transfer. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view showing the positional relation between a print wiring substrate in the magnetic record reproducing apparatus of this invention, a magnetic head on the cylinder, and a pulse transfer, and a condition of the leakage magnetic flux of the pulse transfer; and FIG. 2 is a schematic side view showing a pulse transfer in the magnetic record reproducing apparatus of this invention. FIG. 3 is a plan view showing the core portion of a pulse transfer.
A magnetic recording/reproducing apparatus, comprising a video circuit including a cylinder with a magnetic head and a power circuit provided with a transformer having a core with a gap formed in it. The transformer is positioned so that a direction for connecting a S pole with a N pole created by a leakage magnetic flux from the gap of the core and a direction for connecting a central portion of the cylinder, where the magnetic head is provided, with the central portion of the gap of the transformer together defining a substantially horizontal plane, and the cylinder and the transformer are positioned at a distance so that a reading signal read by the magnetic head is hardly influenced by the leakage magnetic flux.
Summarize the key points of the given document.
[ "This application is a continuation of Ser.", "No. 09/111,460 filed Jul. 7, 1998.", "DETAILED DESCRIPTION OF THE INVENTION 1.", "Field of the Invention This invention relates to a magnetic record reproducing apparatus, and more particularly, to a video tape recorder and a television with a video tape recorder to it.", "Prior Art In the conventional magnetic record reproducing apparatus, and more particularly, a video tape recorder, a power circuit, and a circuit except for it, namely, a video circuit were engaged in another print wiring substrate, and were positioned at a distance to avoid the influences of electric noises and magnetic fields and heat of the power pulse transfer.", "PROBLEMS TO BE SOLVED BY THE INVENTION A shield plate was required to be covered on the power circuit, because the power circuit and the video circuit were hard to avoid the influences of the magnetic field of the pulse transfer for power use in the space limited even if they were positioned at some distance.", "Between the print wiring substrate engaged with the power circuit and the print wiring substrate with the video circuit being engaged with it were required many connecting wirings, whereby the operationally was worse and further electric noises were easy to be provided in these wirings.", "An object of this invention is to provide a magnetic record reproducing apparatus having a configuration aimed at reducing the cost.", "MEANS FOR SOLVING THE PROBLEMS In the magnetic record reproducing apparatus of this invention, the power circuit is provided with a transfer having a core with a gap being formed init, and the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux from the gap of the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer is positioned with such a length being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux.", "Thus, the magnetic flux leaking from the transfer hardly comes out in the direction of the magnetic head.", "Since the cylinder where the magnetic head is provided and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux.", "In the magnetic record reproducing apparatus of this invention, the electronic parts of the power circuit is engaged with a power region which is one region in one print wiring substrate, the electronic parts for the record reproducing use, having a magnetic head except for the electronic parts of the power circuit, is provided with the print wiring substrate mounted in the record reproducing circuit region which is a region except for the power region of the print wiring substrate Also, the power circuit of the power region is provided with a transfer having a core with a gap being formed in it, the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux the gap of the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided, with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux.", "In this case the magnetic flux leak from the transfer hardly comes out in the direction of the magnetic head.", "Since the cylinder where the magnetic head is provided and the transfer is positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux.", "The electronic parts of the power circuit, and the record reproducing electronic parts such as a magnetic head except for the electronic parts of the power circuit are positioned an one print wiring substrate by the positioning in different region on the print wiring substrate.", "In a magnetic record reproducing apparatus of this invention, the above description can be conducted even if the transfer is large in relatively leakage magnetic flux as in the pulse transfer.", "The magnetic record reproducing apparatus is to include the magnetic reproducing specific apparatus.", "PREFERRED EMBODIMENT OF THE INVENTION The embodiment of the magnetic record reproducing apparatus of this invention will be described with reference to FIG. 1 through FIG. 3 .", "FIG. 1 is a schematic plan view showing the positional relation between the print wiring substrate in the magnetic record reproducing apparatus of this invention, the head on the cylinder and the pulse transfer, and the condition or the leakage magnetic flux of the pulse transfer.", "FIG. 2 is a schematic side view of a pulse transfer in the magnetic record reproducing apparatus of this invention.", "FIG. 3 is a plan view showing the core portion of the pulse transfer.", "As shown in FIG. 1, the magnetic record reproducing apparatus of this invention is comprised of a print wiring substrate 100 , a video mechanism parts mounting chassis 200 mounted in the upper portion of the print wiring substrate 100 , a cylinder 300 positioned on the video mechanism parts mounting chassis 200 , and a pulse transfer 400 of the power circuit positioned in the upper portion of the print wiring substrate 100 , and in a region where the video mechanism parts mounting chassis 200 is not mounted.", "The print wiring substrate 100 is comprised of a power region 110 , a record regenerating circuit region 120 except for the power region 110 .", "On the record reproducing circuit region 120 is engaged a main parts of record reproducing electronic parts not shown with a chassis 200 to cover the upper portion side of the main parts.", "In the cylinder 300 is provided with the magnetic head 310 .", "As shown in FIG. 2, the pulse transfer 400 is a split winding type, which is different by 90° from the normal split winding type in the coil winding direction, and is a type of being mounted with the normal split winding type laying horizontally.", "The pulse transfer 400 is comprised of a core portion 410 , a base winding 420 , primary windings 421 , 423 , a secondary winding 422 , and section walls 430 , 431 , 432 , 433 , 434 for separating these windings.", "As shown in FIG. 3, the core portion 410 is an E—E type ferrite core where E and E are combined with.", "The core portion 410 has a gap 410 a at its center.", "The respective lower end sides 430 a, 431 a, 432 a, 433 a , 434 a of the section walls 430 , 431 , 432 433 , 434 are inserted into the through hole portions not shown of the print wiring substrate 100 , thereby forming substrate terminal portions to be soldered and fixed.", "The substrate terminal portion 430 a is connected with one end portion 420 a of the base winding 420 , and the other end portion of the base winding 420 positioned on the inner side in FIG. 2 .", "The substrate terminal portion 431 a is connected with one end portion 421 a of the primary winding 421 , and with the other end portion of the primary winding 421 positioned on the inner side in FIG. 2 .", "The substrate terminal portion 432 a is NC.", "The substrate terminal portion 433 a is connected with an end portion 422 a of the secondary winding 422 , and with the other end portion of the secondary winding 422 positioned on the inner side in FIG. 2 .", "The substrate terminal 434 a is connected with one end portion 423 a of the primary winding 423 , and with the other end portion of the primary winding 423 positioned on the inner side in FIG. 2 .", "High frequency current flows to the pulse transfer 400 .", "Since it is an alternating field in the direction of the magnetic pole, in FIG. 2, the N pole becomes the left side when the S pole is on the right, while the S pole becomes left when the N pole is on the right side.", "Prom the gap 410 a of the core portion 410 is generated a leakage flux 450 (see FIG. 1) in accordance with the magnetic pole direction.", "The leakage magnetic flux 450 is generated in the longitudinal length in the direction of the magnetic pole.", "The pulse transfer 400 is positioned in the power region 110 of the printing wiring substrate 100 so that a direction for connecting the S pole and the N pole with the leakage magnetic flux 450 from the gap 410 a of the core 410 may become almost vertical to the direction for connecting the central portion of the cylinder 300 where the magnetic head 310 is provided and with the central portion of the gap 410 a of the core 410 .", "The power region 110 is provided in the farthest region from the cylinder 300 .", "The pulse transfer 400 should be preferable to be positioned near the center of the power region 110 , as shown in, for example, FIG. 1, to radiate heat to be caused when the high frequency current flows.", "In the magnetic record reproducing apparatus of this invention constructed as above, the pulse transfer 400 is positioned to the magnetic head 310 provided in the cylinder 300 so that the leakage magnetic flux 450 from the pulse transfer 400 may not affect.", "Since the magnetic record reproducing apparatus of this invention does not require a shield plate to be covered on the pulse transfer 400 , the cost can be made lower.", "The print wiring substrate 100 is one substrate comprised of a power region 110 and a record reproducing circuit 120 except for the power region 110 .", "As when two print wiring substrates or more are provided as before, a plurality of connecting wirings are not required to be provided between the print wiring substrate with the power circuit being embodied and the print wiring substrate with the video circuit being embodied.", "Unnecessary operating time which is required to perform the connecting wiring between the print wiring substrates can be saved.", "Further, since no connecting wiring is provided between the print wiring substrates, the circuit configuration is hard to have electric noises generated.", "The configuration of the pulse transfer 400 of such a configuration is not limited to the above description except for the positional relation (for example, shape of the core, number of the windings, positional relation among the windings) among the winding direction, and the terminal portion to be inserted into the print wiring substrate.", "The pulse transfer 400 can be replaced by a different type of transfer which has the same configuration as that in the direction of the leakage magnetic flux and performs the electrically same function.", "In the above description, the video recorder is described as a magnetic record reproducing apparatus of this invention.", "As described above even in the other magnetic record reproducing apparatus such as television with a video tape recorder to it, a tape recorder, the similar effects can be obtained when the magnetic head and the power transfer are provided.", "The description thereof is omitted.", "EFFECT OF THE INVENTION As described above, in the magnetic record reproducing apparatus of the claim 1 of this invention, the power circuit is provided with a transfer having a core with a gap being formed in it, and the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux from the gap at the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided, with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux.", "Thus, the magnetic flux leaked from the transfer hardly comes out in the direction of the magnetic head.", "Since the cylinder where the magnetic head is provided, and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux.", "Thus, a shield plate for covering the entire power circuit is not required as conventionally, thus reducing the cost.", "In the magnetic record reproducing apparatus of the claim 2 of this invention, an electronic parts of the power circuit is engaged with a power region which is one region of one print wiring substrate, the electronic parts for the record reproducing use, having a magnetic head except for the electronic parts of the power circuit, is provided with the print wiring substrate mounted in the record reproducing circuit region which is a region except for the power region of the print wiring substrate.", "Also, the power circuit of the power region is provided with a transfer having a core with a gap being formed in it, the transfer is positioned so that a direction for connecting the S pole with the N pole by the leakage magnetic flux from the gap of the core and a direction for connecting the central portion of the cylinder, where the magnetic head is provided, with the central portion of the gap of the transfer may become approximately vertical, and the cylinder and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux.", "In this case, the magnetic flux leaked from the transfer hardly comes out in the direction of the magnetic head.", "Since the cylinder where the magnetic head is provided, and the transfer are positioned with such a distance being open as a reading signal by the magnetic head is hardly influenced by the leakage magnetic flux, the magnetic head is hardly subject to ill influences by the leakage magnetic flux.", "Thus, the shield plate for covering the entire power circuit is not required as conventionally, thus reducing the cost.", "The electronic parts of the power circuit, and the record reproducing electronic parts such as magnetic head except for the electronic parts of the power circuit are positioned on one print wiring substrate by the positioning in different region on the print wiring substrate.", "Thus, many connecting wirings are not required to be provided between the print wiring substrate where the power circuit is engaged and the print wiring substrate where the video circuit is engaged, as divided in the conventional two print wiring substrates or more.", "Unnecessary operation time which was required to conduct the connecting wiring between the print wiring substrates can be saved.", "Thus, lower cost can be provided.", "Since no connecting wiring between the print wiring substrates is provided the electric noises are hard to be provided.", "In a magnetic record reproducing apparatus of the claim 3 of this invention, the above description can be conducted even if the transfer is large in relatively leakage magnetic flux as in the pulse transfer.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view showing the positional relation between a print wiring substrate in the magnetic record reproducing apparatus of this invention, a magnetic head on the cylinder, and a pulse transfer, and a condition of the leakage magnetic flux of the pulse transfer;", "and FIG. 2 is a schematic side view showing a pulse transfer in the magnetic record reproducing apparatus of this invention.", "FIG. 3 is a plan view showing the core portion of a pulse transfer." ]
CROSS-REFERENCE TO PRIOR APPLICATIONS This is a Non Provisional U.S. Application of a provisional application, claiming the benefit of U.S. Provisional Application No. 61/040,998, filed Mar. 31, 2008. FIELD OF THE INVENTION The present invention relates to pharmaceutical compositions containing naratriptan and a compound selected from the group consisting of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED and methods of using such compositions for treating migraine headaches. BACKGROUND OF THE INVENTION Migraine typically begins with mild to moderate pain that increases in severity over several hours to reach peak severity. The painful phase of the migraine attack persists for 6 to 12 hours in most migraine patients. For those with migraines, the two most important features of migraine medications are providing quick relief and effectively decreasing pain. Migraine patients are dissatisfied with the amount of time to obtain pain relief after taking migraine medication. One group of very effective migraine pain relievers are triptans. The onset of relief or action of the triptans is measured by the rapid time to peak blood concentration (T max ). Migraine patients reported relief of migraine related disability within 2 hours after dosing with a triptan. Migraine patients need rapid relief from their pain and desire a faster time to headache relief. (see Dawn A. Marcus, M.D., “Establishing a Standard of Speed for Assessing the Efficacy of the Serotonin 1B/1D Agonists (Triptan)” Arch Neurol /Volume 58, June 2001 available on www.archneurol.com) Naratriptan has been marketed under the trade name Amerge® by Glaxo Wellcome in the U.S. in tablets (2.5 mg) for oral administration. Naratriptan is a member of the drug class known as scrotonin (5HT) agonists and has been used as a pharmaceutical agent to successfully treats acute migraines. Naratriptan tablets are well absorbed, with about 70% oral bioavailability. Following administration of a 2.5 mg tablet orally, the peak concentrations are obtained in 2 to 3 hours. During a migraine attack, absorption was slower, with a T max of 3 to 4 hours. Because migraine patients desire to return back to their daily task in life within a short time after taking migraine medication, there is a need to have rapid, complete relief of migraine pain within less than 2 hours after drug administration. So far, various efforts to improve the peak concentrations of Naratriptan have failed. SUMMARY OF THE INVENTION The present invention provides a pharmaceutical composition for treating migraines in a subject with a shortened lime period for the onset of maximum peak concentration, comprising of: (a) naratriptan or its salt thereof, (b) at least one compound selected from the group consisting of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED and (c) optionally, a pharmaceutically acceptable excipient. The present invention also provides a tablet for rapid onset of therapeutic effects in treating migraines comprising of a (1) about 0.1 mg to about 100 mg of naratriptan, and (2) from about 10 mg to about 500 mg of at least one of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED. The present invention further provides a method of treating migraine headaches, comprising the step of administering the pharmaceutical composition which contains (a) naratriptan or its salt thereof, (b) at least one compound selected from the group consisting of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED and (c) optionally, a pharmaceutically acceptable excipient, in a subject in need of such a treatment, wherein said pharmaceutical composition, upon oral administration, takes at least 20% less time to reach T max in comparison to administering naratriptan alone. The contents of the patents and publication cited herein and the contents of documents cited in these patents and publications are hereby incorporated herein by reference to the extent permitted. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing the mean plasma concentrations of naratriptan in rats following a single oral administration of naratriptan (10 mg/kg) alone or in combination with one of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED (200 mg/kg). DETAILED DESCRIPTION OF THE INVENTION The term “about” or “approximately” means within an acceptable error range for the particular value as determined by one of ordinary skill in the art, which will depend in part on how the value is measured or determined, i.e., the limitations of the measurement system. For example, “about” can mean within 1 or more than 1 standard deviations, per practice in the art. Alternatively, “about” with respect to pharmaceutical compositions can mean a range of up to 10%, preferably up to 5%. The phrase “pharmaceutically acceptable” refers to compounds or compositions that are physiologically tolerable and do not typically produce an allergic or similar untoward reaction, such as gastric upset, dizziness and the like, when administered to a mammal. As used herein, the term “treat” or “treating” includes one or more of the following: (a) arresting, delaying the onset (i.e., the period prior to clinical manifestation of a disorder) and/or reducing the risk of developing or worsening a disorder; (b) relieving or alleviating at least one symptom of a disorder in a mammal, including for example, hypercalcemia; or (c) relieving or alleviating the intensity and/or duration of a manifestation of a disorder experienced by a mammal including, but not limited to, those which are in response to a given stimulus (e.g., pressure, tissue injury or cold temperature). The term “treat” also includes prophylactically preventing, curing, healing, alleviating, relieving, altering, remedying, ameliorating, improving, or affecting a condition (e.g., a disease), the symptoms of the condition, or the predisposition toward the condition. The term “bioavailability” refers to the rate and extent to which the active ingredient or active moiety is absorbed from a drug product and becomes systematically available. The term “2-HPOD” refers to 8-(2-hydroxyphenoxy)octyldiethanolamine and pharmaceutically acceptable salts. 8-(2-hydroxyphenoxy)octyldiethanolamine has the following chemical structure: The term “2-HPHM” refers to 6-(2-hydroxyphenoxy)hexylmorpholine and its pharmaceutically acceptable salts. 6-(2-hydroxyphenoxy)hexylmorpholine has the following chemical structure: The term “4-BPED” refers to 2-(4-phenoxyphenyl)ethyldiethanolamine its pharmaceutically acceptable salts. 2-(4-phenoxyphenyl)ethyldiethanolamine has the following chemical structure: The term “4-BPED” refers to 2-(biphen-4-yl)ethyldiethanolamine and its pharmaceutically acceptable salts. 2-(biphen-4-yl)ethyldiethanolamine has the following chemical structure: The term “2-PPED” refers to 2-(2-phenoxyphenyl)ethyldiethanolamine and its pharmaceutically acceptable salts. 2-(2-phenoxyphenyl)ethyldiethanolamine has the following chemical structure: The term “AUC 0-last ” refers to area under the curve to the last quantifiable time point. The term “C max ” refers to peak plasma concentration. C max is the maximum absorption of the Naratriptan into the mammal's blood stream. The term “T max ” refers to mean time-to-peak concentrations. A shorter T max correlates with a more rapid onset of action and quicker pain relief in mammals. In one embodiment of the present invention, a naratriptan salt is used in the pharmaceutical composition. Such salt includes hydrochloride, hydrobromide, mesylate, acetate, trifluoroacetate, propionate, fumarate, tartrate, citrate, phosphate, succinate, bisulfate, and besylate salts. In another embodiment of the present invention, the pharmaceutical composition contains naratriptan and one of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED in a weight ratio from about 1:100 to about 1:5, preferably from about 1:75 to about 1:4, more preferably from about 1:50 to about 1:2 and the most preferably from about 1:50 to about 1:1. In another embodiment of the present invention, the method of treating migraine headaches achieves T max in a subject, upon oral administration of the pharmaceutical composition, in at least 20% less time in comparison to administering naratriptan alone, preferably in at least 40% less time, more preferably in at least 50% less time, more preferably in at least 60% less time, more preferably in at least 70% less time, more preferably in at least 75% less time and the most preferably in at least 80% less time. In the present invention, the delivery system is the pharmaceutical formulations which may be in the form of a liquid or solid. Liquid formulations may be water-based. The absorption enhancer was dissolved in deionized water. 10 N NaOH solution was used to help dissolving acid form carriers. HCl was added to lower pH of the absorption enhancer stock solution if the pH was higher than 7.4. Naratriptan powder was added to the absorption enhancer solution 5 minutes before dosing. The final concentration of drug was 10 mg/ml, and the final concentration of carrier was 200 mg/ml for the study. The following examples are given as specific illustrations of the invention. It should be understood, however, that the invention is not limited to the specific details set forth in the examples. All parts and percentages in the examples, as well as in the remainder of the specification, are by weight unless otherwise specified. Example 1 The study was conducted in fasted adult male Sprague-Dawley rats (n=5 for each group as seen in FIG. 1 ). Naratriptan is also designated Nar. Naratriptan was administered alone to rates orally as a control. For oral dosing, single solutions were administrated at time 0, in the following manner: (a) each absorption enhancer carrier (200 mg/kg) in combination with Nar (10 mg/kg) was administered orally to rats; and (b) Nar (10 mg/kg) alone was administered orally to rats. Blood samples were collected by retro-orbital bleed under CO 2 anesthesia pre-dosing (0 minute), and 5, 15, 30, 40, 50, 60, 120 and 240 minutes after dosing. In the control study, where Naratriptan (10 mg/kg) alone was administered to rats, mean peak concentrations were achieved at 27 minutes post-dose. In the administration of Nar/2-HPOD combination, mean peak Naratriptan plasma concentration was observed at 13 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone. In the administration of Nar/2-HPHM combination, mean peak Naratriptan plasma concentration was observed at 12 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone. Both, the Nar/2-HPOD and Nar/2-HPHM combination took approximately ½ the time of Naratriptan alone. In the administration of Nar/4-PPED combination, mean peak Naratriptan plasma concentration was observed at 7.5 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone. Also the mean C max value of the Nar/4-PPED combination was approximately 2-fold higher compared to that obtained following Naratriptan alone. In the administration of Nar/4-BPED combination, mean peak Naratriptan plasma concentration was observed at 9 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone. In the administration of Nar/2-PPED combination, mean peak Naratriptan plasma concentration was observed at 28 minutes post-dose approximately the same lime as seen following Naratriptan alone. However, the mean C max value of the Nar/2-PPED combination was significantly higher than as seen following Naratriptan alone. The testing data are shown in the following table. AUC last C max Group (min * ng/ml) (ng/ml) T max (min) Naratriptan alone (10 mg/kg) 62851 1052 27.0 Naratriptan/2-HPOD (10 mg/kg) 73568 1315 13.0 Naratriptan/2-HPHM (10 mg/kg) 26815 1095 12.0 Naratriptan/4-PPED (10 mg/kg) 52453 933 7.5 Naratriptan/4-BPED (10 mg/kg) 57857 940 9.0 Naratriptan/2-PPED (10 mg/kg) 43725 1357 28.0 The principles, preferred embodiments, and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive. Variations and changes may be made by those skilled in the art, without departing from the spirit of the invention.
The present invention relates to pharmaceutical compositions containing Naratriptan, a compound selected from the group consisting of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED, and optionally, a pharmaceutically acceptable excipient.
Provide a concise summary of the essential information conveyed in the context.
[ "CROSS-REFERENCE TO PRIOR APPLICATIONS This is a Non Provisional U.S. Application of a provisional application, claiming the benefit of U.S. Provisional Application No. 61/040,998, filed Mar. 31, 2008.", "FIELD OF THE INVENTION The present invention relates to pharmaceutical compositions containing naratriptan and a compound selected from the group consisting of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED and methods of using such compositions for treating migraine headaches.", "BACKGROUND OF THE INVENTION Migraine typically begins with mild to moderate pain that increases in severity over several hours to reach peak severity.", "The painful phase of the migraine attack persists for 6 to 12 hours in most migraine patients.", "For those with migraines, the two most important features of migraine medications are providing quick relief and effectively decreasing pain.", "Migraine patients are dissatisfied with the amount of time to obtain pain relief after taking migraine medication.", "One group of very effective migraine pain relievers are triptans.", "The onset of relief or action of the triptans is measured by the rapid time to peak blood concentration (T max ).", "Migraine patients reported relief of migraine related disability within 2 hours after dosing with a triptan.", "Migraine patients need rapid relief from their pain and desire a faster time to headache relief.", "(see Dawn A. Marcus, M.D., “Establishing a Standard of Speed for Assessing the Efficacy of the Serotonin 1B/1D Agonists (Triptan)”", "Arch Neurol /Volume 58, June 2001 available on www.", "archneurol.com) Naratriptan has been marketed under the trade name Amerge® by Glaxo Wellcome in the U.S. in tablets (2.5 mg) for oral administration.", "Naratriptan is a member of the drug class known as scrotonin (5HT) agonists and has been used as a pharmaceutical agent to successfully treats acute migraines.", "Naratriptan tablets are well absorbed, with about 70% oral bioavailability.", "Following administration of a 2.5 mg tablet orally, the peak concentrations are obtained in 2 to 3 hours.", "During a migraine attack, absorption was slower, with a T max of 3 to 4 hours.", "Because migraine patients desire to return back to their daily task in life within a short time after taking migraine medication, there is a need to have rapid, complete relief of migraine pain within less than 2 hours after drug administration.", "So far, various efforts to improve the peak concentrations of Naratriptan have failed.", "SUMMARY OF THE INVENTION The present invention provides a pharmaceutical composition for treating migraines in a subject with a shortened lime period for the onset of maximum peak concentration, comprising of: (a) naratriptan or its salt thereof, (b) at least one compound selected from the group consisting of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED and (c) optionally, a pharmaceutically acceptable excipient.", "The present invention also provides a tablet for rapid onset of therapeutic effects in treating migraines comprising of a (1) about 0.1 mg to about 100 mg of naratriptan, and (2) from about 10 mg to about 500 mg of at least one of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED.", "The present invention further provides a method of treating migraine headaches, comprising the step of administering the pharmaceutical composition which contains (a) naratriptan or its salt thereof, (b) at least one compound selected from the group consisting of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED and (c) optionally, a pharmaceutically acceptable excipient, in a subject in need of such a treatment, wherein said pharmaceutical composition, upon oral administration, takes at least 20% less time to reach T max in comparison to administering naratriptan alone.", "The contents of the patents and publication cited herein and the contents of documents cited in these patents and publications are hereby incorporated herein by reference to the extent permitted.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing the mean plasma concentrations of naratriptan in rats following a single oral administration of naratriptan (10 mg/kg) alone or in combination with one of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED (200 mg/kg).", "DETAILED DESCRIPTION OF THE INVENTION The term “about”", "or “approximately”", "means within an acceptable error range for the particular value as determined by one of ordinary skill in the art, which will depend in part on how the value is measured or determined, i.e., the limitations of the measurement system.", "For example, “about”", "can mean within 1 or more than 1 standard deviations, per practice in the art.", "Alternatively, “about”", "with respect to pharmaceutical compositions can mean a range of up to 10%, preferably up to 5%.", "The phrase “pharmaceutically acceptable”", "refers to compounds or compositions that are physiologically tolerable and do not typically produce an allergic or similar untoward reaction, such as gastric upset, dizziness and the like, when administered to a mammal.", "As used herein, the term “treat”", "or “treating”", "includes one or more of the following: (a) arresting, delaying the onset (i.e., the period prior to clinical manifestation of a disorder) and/or reducing the risk of developing or worsening a disorder;", "(b) relieving or alleviating at least one symptom of a disorder in a mammal, including for example, hypercalcemia;", "or (c) relieving or alleviating the intensity and/or duration of a manifestation of a disorder experienced by a mammal including, but not limited to, those which are in response to a given stimulus (e.g., pressure, tissue injury or cold temperature).", "The term “treat”", "also includes prophylactically preventing, curing, healing, alleviating, relieving, altering, remedying, ameliorating, improving, or affecting a condition (e.g., a disease), the symptoms of the condition, or the predisposition toward the condition.", "The term “bioavailability”", "refers to the rate and extent to which the active ingredient or active moiety is absorbed from a drug product and becomes systematically available.", "The term “2-HPOD”", "refers to 8-(2-hydroxyphenoxy)octyldiethanolamine and pharmaceutically acceptable salts.", "8-(2-hydroxyphenoxy)octyldiethanolamine has the following chemical structure: The term “2-HPHM”", "refers to 6-(2-hydroxyphenoxy)hexylmorpholine and its pharmaceutically acceptable salts.", "6-(2-hydroxyphenoxy)hexylmorpholine has the following chemical structure: The term “4-BPED”", "refers to 2-(4-phenoxyphenyl)ethyldiethanolamine its pharmaceutically acceptable salts.", "2-(4-phenoxyphenyl)ethyldiethanolamine has the following chemical structure: The term “4-BPED”", "refers to 2-(biphen-4-yl)ethyldiethanolamine and its pharmaceutically acceptable salts.", "2-(biphen-4-yl)ethyldiethanolamine has the following chemical structure: The term “2-PPED”", "refers to 2-(2-phenoxyphenyl)ethyldiethanolamine and its pharmaceutically acceptable salts.", "2-(2-phenoxyphenyl)ethyldiethanolamine has the following chemical structure: The term “AUC 0-last ”", "refers to area under the curve to the last quantifiable time point.", "The term “C max ”", "refers to peak plasma concentration.", "C max is the maximum absorption of the Naratriptan into the mammal's blood stream.", "The term “T max ”", "refers to mean time-to-peak concentrations.", "A shorter T max correlates with a more rapid onset of action and quicker pain relief in mammals.", "In one embodiment of the present invention, a naratriptan salt is used in the pharmaceutical composition.", "Such salt includes hydrochloride, hydrobromide, mesylate, acetate, trifluoroacetate, propionate, fumarate, tartrate, citrate, phosphate, succinate, bisulfate, and besylate salts.", "In another embodiment of the present invention, the pharmaceutical composition contains naratriptan and one of 2-HPOD, 2-HPHM, 4-PPED, 4-BPED and 2-PPED in a weight ratio from about 1:100 to about 1:5, preferably from about 1:75 to about 1:4, more preferably from about 1:50 to about 1:2 and the most preferably from about 1:50 to about 1:1.", "In another embodiment of the present invention, the method of treating migraine headaches achieves T max in a subject, upon oral administration of the pharmaceutical composition, in at least 20% less time in comparison to administering naratriptan alone, preferably in at least 40% less time, more preferably in at least 50% less time, more preferably in at least 60% less time, more preferably in at least 70% less time, more preferably in at least 75% less time and the most preferably in at least 80% less time.", "In the present invention, the delivery system is the pharmaceutical formulations which may be in the form of a liquid or solid.", "Liquid formulations may be water-based.", "The absorption enhancer was dissolved in deionized water.", "10 N NaOH solution was used to help dissolving acid form carriers.", "HCl was added to lower pH of the absorption enhancer stock solution if the pH was higher than 7.4.", "Naratriptan powder was added to the absorption enhancer solution 5 minutes before dosing.", "The final concentration of drug was 10 mg/ml, and the final concentration of carrier was 200 mg/ml for the study.", "The following examples are given as specific illustrations of the invention.", "It should be understood, however, that the invention is not limited to the specific details set forth in the examples.", "All parts and percentages in the examples, as well as in the remainder of the specification, are by weight unless otherwise specified.", "Example 1 The study was conducted in fasted adult male Sprague-Dawley rats (n=5 for each group as seen in FIG. 1 ).", "Naratriptan is also designated Nar.", "Naratriptan was administered alone to rates orally as a control.", "For oral dosing, single solutions were administrated at time 0, in the following manner: (a) each absorption enhancer carrier (200 mg/kg) in combination with Nar (10 mg/kg) was administered orally to rats;", "and (b) Nar (10 mg/kg) alone was administered orally to rats.", "Blood samples were collected by retro-orbital bleed under CO 2 anesthesia pre-dosing (0 minute), and 5, 15, 30, 40, 50, 60, 120 and 240 minutes after dosing.", "In the control study, where Naratriptan (10 mg/kg) alone was administered to rats, mean peak concentrations were achieved at 27 minutes post-dose.", "In the administration of Nar/2-HPOD combination, mean peak Naratriptan plasma concentration was observed at 13 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone.", "In the administration of Nar/2-HPHM combination, mean peak Naratriptan plasma concentration was observed at 12 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone.", "Both, the Nar/2-HPOD and Nar/2-HPHM combination took approximately ½ the time of Naratriptan alone.", "In the administration of Nar/4-PPED combination, mean peak Naratriptan plasma concentration was observed at 7.5 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone.", "Also the mean C max value of the Nar/4-PPED combination was approximately 2-fold higher compared to that obtained following Naratriptan alone.", "In the administration of Nar/4-BPED combination, mean peak Naratriptan plasma concentration was observed at 9 minutes post-dose as opposed to 27 minutes as seen following Naratriptan alone.", "In the administration of Nar/2-PPED combination, mean peak Naratriptan plasma concentration was observed at 28 minutes post-dose approximately the same lime as seen following Naratriptan alone.", "However, the mean C max value of the Nar/2-PPED combination was significantly higher than as seen following Naratriptan alone.", "The testing data are shown in the following table.", "AUC last C max Group (min * ng/ml) (ng/ml) T max (min) Naratriptan alone (10 mg/kg) 62851 1052 27.0 Naratriptan/2-HPOD (10 mg/kg) 73568 1315 13.0 Naratriptan/2-HPHM (10 mg/kg) 26815 1095 12.0 Naratriptan/4-PPED (10 mg/kg) 52453 933 7.5 Naratriptan/4-BPED (10 mg/kg) 57857 940 9.0 Naratriptan/2-PPED (10 mg/kg) 43725 1357 28.0 The principles, preferred embodiments, and modes of operation of the present invention have been described in the foregoing specification.", "The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive.", "Variations and changes may be made by those skilled in the art, without departing from the spirit of the invention." ]
BACKGROUND OF THE INVENTION This invention relates to improved apparatus for the filleting of fish. The traditional methods and facilities used for hand filleting of the more common species of fish such as codfish, have not varied significantly over the past many years. The usual procedure involves removing a fish from a fish box and placing it flat on a cutting table. Then, by using one or a series of knife cuts, depending on the size and type of fish as well as the technique preferred by the individual operator, a fillet is removed from the first side of the fish. The fillet is placed in a container and then the fish is rotated 180°, flipped over and a fillet is removed from the second side. The second fillet is placed in the container and the frame (head and backbone) of the fish is then discarded via a chute located to one end of the table. The above-described procedure can be carried out fairly rapidly by an experienced operator, and in order to provide an incentive to the operator, most fish plants pay a bonus, which bonus is dependent on the operators' total productivity in terms of the weight of fish filleted per shift. Productivity however is not the only factor in an efficient processing operation. The "yield", which is a measure of the weight of fillets removed as compared with the overall weight of the fish, is also of great importance. A careless or unskilled operator may waste a great deal of edible flesh, i.e. more flesh than necessary may be left on the frame. For this reason fish plants traditionally pay close attention to the average yield as well as the total production of each operator. It has been known for some time that the vast majority of operators obtain a higher yield on the first fillet removed from the frame as compared with the second fillet. Studies have shown that there are two main reasons for this. When filleting the second side of the fish, the first fillet has already been removed from the frame resulting in: (a) relatively little clearance between the cutting surface and the cutting table making it difficult to pass the filleting knife parallel to the fish backbone; (b) a gap between the cutting table surface and the fish frame in the area adjacent to the head. Therefore, the fish bows downwardly under the pressure of the cutting knife since there is no firm support underneath the fish frame. Although the prior art has provided a number of devices for holding or supporting fish during a cleaning or filleting operation, none of them deal adequately with the basic problem created by the bowing downwardly of the fish and the curving of its spine after the first fillet has been removed and the fish has been turned over. U.S. Pat. No. 4,030,164 issued June 21, 1977 to Fick shows a filleting board having a curvate opening in its surface arranged so that the gill cover of the fish enters into it thereby to assist in retaining the fish in position. Most commercially utilized species of fish have gill covers streamlined with the head; hence guiding the gill cover into the opening would require a special time consuming effort which would result in productivity loss. From an operational point of view, the filleting of fish on Fick's device would require the operator to remove one fillet from the backside of the fish and the other fillet from the abdomen side, unless the operator would cut one fillet and then proceed to the opposite side of the board to remove the second fillet facing the backside of the fish. Needless to say, filleting from the back and abdomen side would result in poor yield and the necessary additional movement of the operator would take extra time and room. There is also no suggestion in the above patent of any means to support the cut side of the fish as well as the fish head so that the latter is retained as a straight extension of the spine of the fish during removal of the second fillet. The bowing problem referred to above is not dealt with by the Fick patent. Studies have also been carried out by others on this problem especially by P. J. Amaria et al and reported in a paper entitled "Productivity Studies In Fish Processing"--Proposed New Method of Manual Filleting of Cod (presented at the Atlantic Fisheries Technological Conference, Williamsberg, Va. 1978). In that paper, a filleting board design is described, which design includes a large notch at one end of the board to receive the fish head during removal of the second fillet. The board surface was also sloped away from the operator at about an 8° angle to make it easier for the operator to run the knife parallel to the cutting board surface. While the sloped board surface has been found to be advantageous, the particular notched board design described by Amaria et al has been found, as a result of subsequent tests, to have numerous disadvantages. There is an empty space below the notch and hence the fish head tended to droop downwardly into it in many cases thus causing the spine of the fish to arch upwardly. In other cases large fish heads would not properly enter into the notch. As a result the fish head was not supported in general alignment with the backbone. Furthermore the notch described by Amaria did not properly capture the gill or the cut portion of the head with the result being that the head tended to jump out of the notch when pressure was applied to the fish during fillet removal. SUMMARY OF THE INVENTION It is a general object of the present invention to provide an improved filleting board which alleviates the problems described above and which provides for improved yield without sacrificing productivity. Thus, the invention in one aspect, provides a fish filleting board including an elongated body having a major top surface. A recess in the top surface defines a floor providing a minor support surface disposed below said major top surface (in the operational position of the board). This minor support surface is arranged to receive and support the head of a fish in approximate alignment with the spine of the fish after removal of the first fillet therefrom while at the same time the cut portion of the fish body lies flat on the major top surface with the spine thereof lying parallel to it. An abrupt step is defined between a portion of the top surface and the floor of the recess and against which the cut portion of the fish head may be lodged to stabilize the fish during removal of the second fillet. The support and stability afforded by the above recited structures enable filleting techniques to be used which result in a considerably higher yield insofar as the second fillet is concerned. The above-noted step preferably includes a wall portion which is undercut so that such wall portion is at an acute angle with respect to said major top surface. In use, the cut portion of the fish head, which follows closely adjacent to the gill opening, can be engaged firmly with said step as the fish head is pushed against said wall portion. The above-noted recess preferably extends from one of the ends of the board toward an intermediate portion of the body. The frame of the fish is moved along such recess and away from the end of the board after the second fillet has been removed. The above-noted step preferably extends in a smoothly curved path from one of the ends of the body toward the intermediate portion, and there curves smoothly around as seen in top plan view and proceeds in the opposite direction for a selected distance. The undercut wall portion is preferably located in the intermediate portion of the body where the path curves smoothly around and begins to proceed in the opposite direction. As a further feature, the floor of the recess has a shallow concavity defined therein closely adjacent said undercut wall portion, which concavity slopes shallowly downwardly generally toward said undercut wall portion thereby to assist in providing support for a range of sizes of fish heads. In a typical form of the invention the major top surface is essentially flat and the board is arranged so that, in its operational position, the flat major surface of the board slopes downwardly from the horizontal by an angle of 4 to about 12 degrees in a direction transverse to the longitudinal axis of the board. Suitable means are provided for supplying a flow of water transversely of the board to flush slime and scales off the board surface. The board body is preferably of a unitary synthetic plastics material for purposes of ease of fabrication, cleanliness etc. BRIEF DESCRIPTION OF THE VIEWS OF DRAWINGS An embodiment of the invention will now be described with reference to the drawings wherein: FIGS. 1 and 2 illustrate prior art filleting techniques; FIG. 3 is a perspective view of the filleting board in accordance with the invention; FIG. 4 is a top plan view of the filleting board; FIG. 5 is a section view taken along line 5--5 of FIG. 4; FIG. 5A is a modified section view along line 5A--5A and looking in the direction of the arrows; FIG. 5B is a pictorial view looking into the recess in the board from a point above the board; FIG. 6 is an elevation view of one end of the board; FIG. 7 is an elevation view of the opposite end of the board; FIG. 8 is a section view taken along line 8--8 of FIG. 4; FIG. 9 is a diagrammatic section view of the board illustrating the manner in which the fish is engaged with the board during the removal of the second fillet; FIGS. 10 and 11 are cross-section views illustrating the relationship of the knife to the board surface during removal of the first and second fillets. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIGS. 1 and 2, conventional filleting techniques are depicted. The precise sequence of knife cuts need not be described since the sequence will depend on both the operator and the size and species of fish. It suffices to say that, in general, in the course of removing the first fillet, the fish is laid on the cutting board surface as in FIG. 1, stabilized by downward hand pressure P, while a series of knife cuts are made including two knife cuts into the head region, which cuts are designated by the references C1 and C2. The filleting knife is also made to move along the spine of the fish (cut C3) to separate the first fillet. By virtue of the two cuts C1 and C2 in the head region of the fish, an experienced operator can remove substantially all of the marketable flesh from the triangular region illustrated by the shading immediately behind the head of the fish thus contributing to a high yield. The situation regarding the second fillet removal is somewhat different. The operator turns the fish over so that it rests on the head and cut side, rotates it end for end and applies hand pressure P to stabilize it. A single knife cut C1 is then made, the cut line beginning at the surface just rearwardly of the gill cover and entering inwardly and forwardly and thence curving gradually around and extending rearwardly in close parallelism to the spine of the fish. After the removal of the second fillet, the frame of the fish is discarded together with the marketable flesh remaining on it. The technique described above gives rise to a lower yield for the second fillet because the flesh in the shaded triangular region behind the head is not removed with the fillet but instead is discarded with the frame. The cutting technique giving rise to this wastage is necessitated by the fact that the spine of the fish is not properly supported along its length and bows downwardly, especially in the region near to the head under the pressure applied by the operator. It has been found, under these conditions, to be impractical in terms of productivity and safety requirements to use two cuts into the head region in an effort to remove all the edible flesh. The net result is that the average yield for the second fillet is usually well over 1% less than the yield for the first fillet. When considering the large tonnages of fish processed annually, the yield loss is quite significant. A preferred form of filleting board for alleviating the above problem is shown in FIGS. 3-8 and the method for using same is illustrated in FIGS. 9-11. As illustrated, the filleting board 10 is defined by an elongated rectangular body having a major top surface 12 which is essentially flat. Top surface 12 is sloped relative to the base of the board by a suitable angle from 4 to 12 degrees, preferably from 5 to 8 degrees, for reasons to be discussed hereafter. The top surface 12 may be provided with shallow "pebbles" which serve to frictionally grip a fish placed on it, without, at the same time, providing crevices which would tend to hold dirt and bacteria. The longitudinal sides 13 and 14 of the board may be provided with shallow notches 16 (FIG. 4) which engage with fittings (not shown) located on a standard filleting table thereby to prevent the board from sliding relative to such table during use. The boards will normally be supplied in a standard width, but in a series of overall lengths thereby to render the boards useable with a variety of lengths of cutting tables. The board may be made (such as by moulding) from any one of several plastic materials, such as high density polyethylene for ease of manufacture, durability, sanitary purposes etc. Particular reference will now be had to FIGS. 4-7. FIGS. 4 and 5 are shown as being laid out on a 1 inch (2.54 cm) square grid thereby to better illustrate the size and proportions of the various elements of this embodiment of the invention. The board and particularly the features of the head holding recess are most applicable to groundfish species such as cod, haddock, pollock, cusk, hake and some flat fish species such as small halibut 2-6 kg and larger turbot. Other flat fish species, i.e. flounder, greysole, lemonsole, etc. having a relatively small and thin head would not usually benefit from the head holding recess feature of the board; however, the sloping top surface of the board (12) enables the operator to insert the knife and run it at the correct angle with considerably reduced effort in comparison to the same operation performed on a flat board resulting in higher average filleting yield. This feature will be described in further detail hereafter. The invention, however, is not to be limited to the example shown but is to extend to all reasonable modifications and variations thereof as hereafter defined. A relatively large recess 18 is provided in the top surface of the board, such recess extending inwardly from one end 20 of the board to an intermediate portion of same. The recess 18 includes a floor portion 22 defining a minor support surface which is disposed below the major top surface 12 in the normal operational position of the board. An abrupt step 24 is defined between a portion of top surface 12 and the floor 22 of the recess and against a part of which the cut portion of the fish head may be lodged to stabilize the fish during removal of the second fillet. The step 24 includes a wall 26, a portion 28 of which is undercut so that it is at an acute angle relative to the major top surface 12. The outline of the undercut portion 28 is shown by the dashed line 30 in FIG. 4. In the embodiment shown, this acute angle is about 30° in the region of section line 5--5 in which region the lip 34 defining the extreme terminal edge of the step is relatively thin, (e.g. 1/16 inch radius). This lip remains relatively thin in both directions away from section line 5--5 as seen in FIG. 5A with the lip thickness rapidly increasing adjacent points 32, at which points the undercut portion of the step terminates. The step 24, again as best seen in FIG. 4, extends in a smoothly curved path from end 18 toward the intermediate region of the board and thence curves smoothly around and begins to proceed back toward end 18 for a short distance before terminating at 36. The above-noted undercut portion 28 of the step is located in this intermediate portion of the body where the path curves smoothly around and begins to proceed in the opposite direction. The above-noted floor 22 of the recess includes a shallowly concavely contoured floor portion 40 which serves to support the fish head during second fillet removal. Floor portion 40 slopes shallowly downwardly toward the undercut portion of the step 24 as best seen in section in FIG. 5. Floor portion 40 has a free forward edge 42, the contour of which, in plan, parallels that of the lip 34 as clearly seen in FIG. 4. A substantial gap or opening is defined between edge 42 and the undercut wall portion 28. The provision of this gap, in addition to accommodating a portion of the fish head as hereafter described, allows debris from the cutting operation and fluids to drain away from the board. The gap also facilitates the manufacturing operations used to produce the board. The rear margin of the floor portion 40 is defined by line 41 (FIGS. 4 and 5). In the embodiment shown, both the degree of slope of floor portion 40 and the maximum depth of the concavity are relatively small, the maximum depth D being about 1/8 inch and the average slope being in the order of 8° relative to the base of the board. The basic function of the floor portion 40 is to support the fish head approximately in alignment with the spine when the cut side of the fish is lying on the major top surface 12 during removal of the second fillet. The configuration described is capable of accommodating a wide variety of sizes of fish head while still supporting same in such a way that the cut side of the fish is fully supported along its length with the spine parallel to the board top surface. The shallowly concave floor portion 40 of the board slopes downward as noted above and enables the board to accommodate the head of a fairly large fish. Consequently, when a large fish is being filleted, and the gill cover is inserted into the slot, because of the size of the fish's head and the slope of the floor portion 40 the tip of the fish's nose points slightly upward and extends outward beyond the rear margin 41 of the floor portion 40. However, the flesh laden posterior to the head part of the fish will almost be a straight line extension of the spine--a filleting condition most desirable for extracting maximum fish flesh in a fillet form derived from the head area. In the case of small fish, the tip of the nose will drop slightly downward from the level of the major top surface and will find support on floor portion 40 and again that flesh laden posterior to the head part of the fish will be almost a straight line extension of the spine similar to the situation encountered in the filleting of large fish as described above. In both cases, i.e. relatively large fish where the nose points slightly upwardly, and relatively small fish where the nose points slightly downwardly, it can still be said that the fish head is approximately in alignment with the spine when the cut side of the fish is lying flat on the major top surface 12. The undercut wall portion 28 coupled with the relatively large gap between wall portion 28 and edge 42 permits the cut portion of the fish head to be engaged firmly in a wedge-like fashion with the step 24 as the head is pushed against the step during the filleting procedure. The head is held firmly in place and does not tend to jump out of position due to the wedging action provided. It was noted previously that the major top surface of the board is sloped relative to the base surface of the board. Board side 14 is the "high" side of the board, this being the side from which the operator works, the slope assisting in allowing the operator to run his knife parallel to the board top surface and to the spine of the fish during removal of the first and second fillets (see FIGS. 10 and 11). The sloping top surface also facilitates the continuous cleaning of the board and for this purpose a washing groove 50 is provided in such surface, this groove extending parallel to the "high" side 14 of the board from closely adjacent step 24 to a point close to the second end 20. The groove 50 is in communication via spaced holes 51 on elongated bore 52 in the board to which a nipple (not shown) may be connected to supply water under pressure to the groove. In use, the water flows steadily from the groove, flushing away scales and slime. The manner in which the cutting board is used will be readily apparent from the above and from FIGS. 9-11. FIG. 10 shows the first fillet being removed using generally conventional techniques with the fish lying on the major top surface of the board. After removal of the first fillet, the fish is turned end for end and flipped over on its cut side. The head is located in the recess 18 (FIG. 9) and supported on the sloped concavely contoured floor portion 40 in approximate alignment with the spine of the fish, the spine lying on and extending parallel to the major top surface 12. The cut portion of the head is wedged into the undercut portion 28 of the step 24. Then, stabilizing the fish with hand pressure P, the second fillet is removed using, as part of the cutting sequence, two cuts into the head region along cut lines C1 and C2 thereby enabling the triangular region of flesh (which was previously wasted) to be removed as a part of the second fillet. After completion of the cutting sequence, the frame of the fish is slid along the floor of recess 18 in the direction of arrow E outwardly and away from end 20 of the board and into a refuse chute (not shown). It has been found in the course of several trial production runs that the use of the filleting board has resulted in a significant increase in yield (often exceeding 1%) without, after an initial operator training period, adversely affecting productivity. Indeed, after a period of time, many operators found that by using the board they suffered considerably less fatigue and were thus able to increase their productivity without adverse effects. Fish plant operators will benefit from the increased yield and the potential increase in productivity and at the same time will appreciate the relatively low initial cost of the board, the ease with which it can be cleaned and the fact that its installation does not require significant modification of existing in-plant facilities.
The invention provides an improved fish filleting board including an elongated body having a major top surface. A recess in the top surface defines a floor providing a minor support surface disposed below said major top surface (in the operational position of the board). This minor support surface is arranged to receive and support the head of a fish in approximate alignment with the spine of the fish after removal of the first fillet therefrom while at the same time the cut portion of the fish body lies flat on the major top surface with the spine thereof lying parallel to it. An abrupt step is defined between a portion of the top surface and the floor of the recess and against which the cut portion of the fish head may be lodged to stabilize the fish during removal of the second fillet. The support and stability afforded by the above recited structures enable filleting techniques to be used which result in a considerably higher yield insofar as the second fillet is concerned.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "BACKGROUND OF THE INVENTION This invention relates to improved apparatus for the filleting of fish.", "The traditional methods and facilities used for hand filleting of the more common species of fish such as codfish, have not varied significantly over the past many years.", "The usual procedure involves removing a fish from a fish box and placing it flat on a cutting table.", "Then, by using one or a series of knife cuts, depending on the size and type of fish as well as the technique preferred by the individual operator, a fillet is removed from the first side of the fish.", "The fillet is placed in a container and then the fish is rotated 180°, flipped over and a fillet is removed from the second side.", "The second fillet is placed in the container and the frame (head and backbone) of the fish is then discarded via a chute located to one end of the table.", "The above-described procedure can be carried out fairly rapidly by an experienced operator, and in order to provide an incentive to the operator, most fish plants pay a bonus, which bonus is dependent on the operators'", "total productivity in terms of the weight of fish filleted per shift.", "Productivity however is not the only factor in an efficient processing operation.", "The "yield", which is a measure of the weight of fillets removed as compared with the overall weight of the fish, is also of great importance.", "A careless or unskilled operator may waste a great deal of edible flesh, i.e. more flesh than necessary may be left on the frame.", "For this reason fish plants traditionally pay close attention to the average yield as well as the total production of each operator.", "It has been known for some time that the vast majority of operators obtain a higher yield on the first fillet removed from the frame as compared with the second fillet.", "Studies have shown that there are two main reasons for this.", "When filleting the second side of the fish, the first fillet has already been removed from the frame resulting in: (a) relatively little clearance between the cutting surface and the cutting table making it difficult to pass the filleting knife parallel to the fish backbone;", "(b) a gap between the cutting table surface and the fish frame in the area adjacent to the head.", "Therefore, the fish bows downwardly under the pressure of the cutting knife since there is no firm support underneath the fish frame.", "Although the prior art has provided a number of devices for holding or supporting fish during a cleaning or filleting operation, none of them deal adequately with the basic problem created by the bowing downwardly of the fish and the curving of its spine after the first fillet has been removed and the fish has been turned over.", "U.S. Pat. No. 4,030,164 issued June 21, 1977 to Fick shows a filleting board having a curvate opening in its surface arranged so that the gill cover of the fish enters into it thereby to assist in retaining the fish in position.", "Most commercially utilized species of fish have gill covers streamlined with the head;", "hence guiding the gill cover into the opening would require a special time consuming effort which would result in productivity loss.", "From an operational point of view, the filleting of fish on Fick's device would require the operator to remove one fillet from the backside of the fish and the other fillet from the abdomen side, unless the operator would cut one fillet and then proceed to the opposite side of the board to remove the second fillet facing the backside of the fish.", "Needless to say, filleting from the back and abdomen side would result in poor yield and the necessary additional movement of the operator would take extra time and room.", "There is also no suggestion in the above patent of any means to support the cut side of the fish as well as the fish head so that the latter is retained as a straight extension of the spine of the fish during removal of the second fillet.", "The bowing problem referred to above is not dealt with by the Fick patent.", "Studies have also been carried out by others on this problem especially by P. J. Amaria et al and reported in a paper entitled "Productivity Studies In Fish Processing"--Proposed New Method of Manual Filleting of Cod (presented at the Atlantic Fisheries Technological Conference, Williamsberg, Va.", "1978).", "In that paper, a filleting board design is described, which design includes a large notch at one end of the board to receive the fish head during removal of the second fillet.", "The board surface was also sloped away from the operator at about an 8° angle to make it easier for the operator to run the knife parallel to the cutting board surface.", "While the sloped board surface has been found to be advantageous, the particular notched board design described by Amaria et al has been found, as a result of subsequent tests, to have numerous disadvantages.", "There is an empty space below the notch and hence the fish head tended to droop downwardly into it in many cases thus causing the spine of the fish to arch upwardly.", "In other cases large fish heads would not properly enter into the notch.", "As a result the fish head was not supported in general alignment with the backbone.", "Furthermore the notch described by Amaria did not properly capture the gill or the cut portion of the head with the result being that the head tended to jump out of the notch when pressure was applied to the fish during fillet removal.", "SUMMARY OF THE INVENTION It is a general object of the present invention to provide an improved filleting board which alleviates the problems described above and which provides for improved yield without sacrificing productivity.", "Thus, the invention in one aspect, provides a fish filleting board including an elongated body having a major top surface.", "A recess in the top surface defines a floor providing a minor support surface disposed below said major top surface (in the operational position of the board).", "This minor support surface is arranged to receive and support the head of a fish in approximate alignment with the spine of the fish after removal of the first fillet therefrom while at the same time the cut portion of the fish body lies flat on the major top surface with the spine thereof lying parallel to it.", "An abrupt step is defined between a portion of the top surface and the floor of the recess and against which the cut portion of the fish head may be lodged to stabilize the fish during removal of the second fillet.", "The support and stability afforded by the above recited structures enable filleting techniques to be used which result in a considerably higher yield insofar as the second fillet is concerned.", "The above-noted step preferably includes a wall portion which is undercut so that such wall portion is at an acute angle with respect to said major top surface.", "In use, the cut portion of the fish head, which follows closely adjacent to the gill opening, can be engaged firmly with said step as the fish head is pushed against said wall portion.", "The above-noted recess preferably extends from one of the ends of the board toward an intermediate portion of the body.", "The frame of the fish is moved along such recess and away from the end of the board after the second fillet has been removed.", "The above-noted step preferably extends in a smoothly curved path from one of the ends of the body toward the intermediate portion, and there curves smoothly around as seen in top plan view and proceeds in the opposite direction for a selected distance.", "The undercut wall portion is preferably located in the intermediate portion of the body where the path curves smoothly around and begins to proceed in the opposite direction.", "As a further feature, the floor of the recess has a shallow concavity defined therein closely adjacent said undercut wall portion, which concavity slopes shallowly downwardly generally toward said undercut wall portion thereby to assist in providing support for a range of sizes of fish heads.", "In a typical form of the invention the major top surface is essentially flat and the board is arranged so that, in its operational position, the flat major surface of the board slopes downwardly from the horizontal by an angle of 4 to about 12 degrees in a direction transverse to the longitudinal axis of the board.", "Suitable means are provided for supplying a flow of water transversely of the board to flush slime and scales off the board surface.", "The board body is preferably of a unitary synthetic plastics material for purposes of ease of fabrication, cleanliness etc.", "BRIEF DESCRIPTION OF THE VIEWS OF DRAWINGS An embodiment of the invention will now be described with reference to the drawings wherein: FIGS. 1 and 2 illustrate prior art filleting techniques;", "FIG. 3 is a perspective view of the filleting board in accordance with the invention;", "FIG. 4 is a top plan view of the filleting board;", "FIG. 5 is a section view taken along line 5--5 of FIG. 4;", "FIG. 5A is a modified section view along line 5A--5A and looking in the direction of the arrows;", "FIG. 5B is a pictorial view looking into the recess in the board from a point above the board;", "FIG. 6 is an elevation view of one end of the board;", "FIG. 7 is an elevation view of the opposite end of the board;", "FIG. 8 is a section view taken along line 8--8 of FIG. 4;", "FIG. 9 is a diagrammatic section view of the board illustrating the manner in which the fish is engaged with the board during the removal of the second fillet;", "FIGS. 10 and 11 are cross-section views illustrating the relationship of the knife to the board surface during removal of the first and second fillets.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIGS. 1 and 2, conventional filleting techniques are depicted.", "The precise sequence of knife cuts need not be described since the sequence will depend on both the operator and the size and species of fish.", "It suffices to say that, in general, in the course of removing the first fillet, the fish is laid on the cutting board surface as in FIG. 1, stabilized by downward hand pressure P, while a series of knife cuts are made including two knife cuts into the head region, which cuts are designated by the references C1 and C2.", "The filleting knife is also made to move along the spine of the fish (cut C3) to separate the first fillet.", "By virtue of the two cuts C1 and C2 in the head region of the fish, an experienced operator can remove substantially all of the marketable flesh from the triangular region illustrated by the shading immediately behind the head of the fish thus contributing to a high yield.", "The situation regarding the second fillet removal is somewhat different.", "The operator turns the fish over so that it rests on the head and cut side, rotates it end for end and applies hand pressure P to stabilize it.", "A single knife cut C1 is then made, the cut line beginning at the surface just rearwardly of the gill cover and entering inwardly and forwardly and thence curving gradually around and extending rearwardly in close parallelism to the spine of the fish.", "After the removal of the second fillet, the frame of the fish is discarded together with the marketable flesh remaining on it.", "The technique described above gives rise to a lower yield for the second fillet because the flesh in the shaded triangular region behind the head is not removed with the fillet but instead is discarded with the frame.", "The cutting technique giving rise to this wastage is necessitated by the fact that the spine of the fish is not properly supported along its length and bows downwardly, especially in the region near to the head under the pressure applied by the operator.", "It has been found, under these conditions, to be impractical in terms of productivity and safety requirements to use two cuts into the head region in an effort to remove all the edible flesh.", "The net result is that the average yield for the second fillet is usually well over 1% less than the yield for the first fillet.", "When considering the large tonnages of fish processed annually, the yield loss is quite significant.", "A preferred form of filleting board for alleviating the above problem is shown in FIGS. 3-8 and the method for using same is illustrated in FIGS. 9-11.", "As illustrated, the filleting board 10 is defined by an elongated rectangular body having a major top surface 12 which is essentially flat.", "Top surface 12 is sloped relative to the base of the board by a suitable angle from 4 to 12 degrees, preferably from 5 to 8 degrees, for reasons to be discussed hereafter.", "The top surface 12 may be provided with shallow "pebbles"", "which serve to frictionally grip a fish placed on it, without, at the same time, providing crevices which would tend to hold dirt and bacteria.", "The longitudinal sides 13 and 14 of the board may be provided with shallow notches 16 (FIG.", "4) which engage with fittings (not shown) located on a standard filleting table thereby to prevent the board from sliding relative to such table during use.", "The boards will normally be supplied in a standard width, but in a series of overall lengths thereby to render the boards useable with a variety of lengths of cutting tables.", "The board may be made (such as by moulding) from any one of several plastic materials, such as high density polyethylene for ease of manufacture, durability, sanitary purposes etc.", "Particular reference will now be had to FIGS. 4-7.", "FIGS. 4 and 5 are shown as being laid out on a 1 inch (2.54 cm) square grid thereby to better illustrate the size and proportions of the various elements of this embodiment of the invention.", "The board and particularly the features of the head holding recess are most applicable to groundfish species such as cod, haddock, pollock, cusk, hake and some flat fish species such as small halibut 2-6 kg and larger turbot.", "Other flat fish species, i.e. flounder, greysole, lemonsole, etc.", "having a relatively small and thin head would not usually benefit from the head holding recess feature of the board;", "however, the sloping top surface of the board (12) enables the operator to insert the knife and run it at the correct angle with considerably reduced effort in comparison to the same operation performed on a flat board resulting in higher average filleting yield.", "This feature will be described in further detail hereafter.", "The invention, however, is not to be limited to the example shown but is to extend to all reasonable modifications and variations thereof as hereafter defined.", "A relatively large recess 18 is provided in the top surface of the board, such recess extending inwardly from one end 20 of the board to an intermediate portion of same.", "The recess 18 includes a floor portion 22 defining a minor support surface which is disposed below the major top surface 12 in the normal operational position of the board.", "An abrupt step 24 is defined between a portion of top surface 12 and the floor 22 of the recess and against a part of which the cut portion of the fish head may be lodged to stabilize the fish during removal of the second fillet.", "The step 24 includes a wall 26, a portion 28 of which is undercut so that it is at an acute angle relative to the major top surface 12.", "The outline of the undercut portion 28 is shown by the dashed line 30 in FIG. 4. In the embodiment shown, this acute angle is about 30° in the region of section line 5--5 in which region the lip 34 defining the extreme terminal edge of the step is relatively thin, (e.g. 1/16 inch radius).", "This lip remains relatively thin in both directions away from section line 5--5 as seen in FIG. 5A with the lip thickness rapidly increasing adjacent points 32, at which points the undercut portion of the step terminates.", "The step 24, again as best seen in FIG. 4, extends in a smoothly curved path from end 18 toward the intermediate region of the board and thence curves smoothly around and begins to proceed back toward end 18 for a short distance before terminating at 36.", "The above-noted undercut portion 28 of the step is located in this intermediate portion of the body where the path curves smoothly around and begins to proceed in the opposite direction.", "The above-noted floor 22 of the recess includes a shallowly concavely contoured floor portion 40 which serves to support the fish head during second fillet removal.", "Floor portion 40 slopes shallowly downwardly toward the undercut portion of the step 24 as best seen in section in FIG. 5. Floor portion 40 has a free forward edge 42, the contour of which, in plan, parallels that of the lip 34 as clearly seen in FIG. 4. A substantial gap or opening is defined between edge 42 and the undercut wall portion 28.", "The provision of this gap, in addition to accommodating a portion of the fish head as hereafter described, allows debris from the cutting operation and fluids to drain away from the board.", "The gap also facilitates the manufacturing operations used to produce the board.", "The rear margin of the floor portion 40 is defined by line 41 (FIGS.", "4 and 5).", "In the embodiment shown, both the degree of slope of floor portion 40 and the maximum depth of the concavity are relatively small, the maximum depth D being about 1/8 inch and the average slope being in the order of 8° relative to the base of the board.", "The basic function of the floor portion 40 is to support the fish head approximately in alignment with the spine when the cut side of the fish is lying on the major top surface 12 during removal of the second fillet.", "The configuration described is capable of accommodating a wide variety of sizes of fish head while still supporting same in such a way that the cut side of the fish is fully supported along its length with the spine parallel to the board top surface.", "The shallowly concave floor portion 40 of the board slopes downward as noted above and enables the board to accommodate the head of a fairly large fish.", "Consequently, when a large fish is being filleted, and the gill cover is inserted into the slot, because of the size of the fish's head and the slope of the floor portion 40 the tip of the fish's nose points slightly upward and extends outward beyond the rear margin 41 of the floor portion 40.", "However, the flesh laden posterior to the head part of the fish will almost be a straight line extension of the spine--a filleting condition most desirable for extracting maximum fish flesh in a fillet form derived from the head area.", "In the case of small fish, the tip of the nose will drop slightly downward from the level of the major top surface and will find support on floor portion 40 and again that flesh laden posterior to the head part of the fish will be almost a straight line extension of the spine similar to the situation encountered in the filleting of large fish as described above.", "In both cases, i.e. relatively large fish where the nose points slightly upwardly, and relatively small fish where the nose points slightly downwardly, it can still be said that the fish head is approximately in alignment with the spine when the cut side of the fish is lying flat on the major top surface 12.", "The undercut wall portion 28 coupled with the relatively large gap between wall portion 28 and edge 42 permits the cut portion of the fish head to be engaged firmly in a wedge-like fashion with the step 24 as the head is pushed against the step during the filleting procedure.", "The head is held firmly in place and does not tend to jump out of position due to the wedging action provided.", "It was noted previously that the major top surface of the board is sloped relative to the base surface of the board.", "Board side 14 is the "high"", "side of the board, this being the side from which the operator works, the slope assisting in allowing the operator to run his knife parallel to the board top surface and to the spine of the fish during removal of the first and second fillets (see FIGS. 10 and 11).", "The sloping top surface also facilitates the continuous cleaning of the board and for this purpose a washing groove 50 is provided in such surface, this groove extending parallel to the "high"", "side 14 of the board from closely adjacent step 24 to a point close to the second end 20.", "The groove 50 is in communication via spaced holes 51 on elongated bore 52 in the board to which a nipple (not shown) may be connected to supply water under pressure to the groove.", "In use, the water flows steadily from the groove, flushing away scales and slime.", "The manner in which the cutting board is used will be readily apparent from the above and from FIGS. 9-11.", "FIG. 10 shows the first fillet being removed using generally conventional techniques with the fish lying on the major top surface of the board.", "After removal of the first fillet, the fish is turned end for end and flipped over on its cut side.", "The head is located in the recess 18 (FIG.", "9) and supported on the sloped concavely contoured floor portion 40 in approximate alignment with the spine of the fish, the spine lying on and extending parallel to the major top surface 12.", "The cut portion of the head is wedged into the undercut portion 28 of the step 24.", "Then, stabilizing the fish with hand pressure P, the second fillet is removed using, as part of the cutting sequence, two cuts into the head region along cut lines C1 and C2 thereby enabling the triangular region of flesh (which was previously wasted) to be removed as a part of the second fillet.", "After completion of the cutting sequence, the frame of the fish is slid along the floor of recess 18 in the direction of arrow E outwardly and away from end 20 of the board and into a refuse chute (not shown).", "It has been found in the course of several trial production runs that the use of the filleting board has resulted in a significant increase in yield (often exceeding 1%) without, after an initial operator training period, adversely affecting productivity.", "Indeed, after a period of time, many operators found that by using the board they suffered considerably less fatigue and were thus able to increase their productivity without adverse effects.", "Fish plant operators will benefit from the increased yield and the potential increase in productivity and at the same time will appreciate the relatively low initial cost of the board, the ease with which it can be cleaned and the fact that its installation does not require significant modification of existing in-plant facilities." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser. No. 12/664,373, filed Dec. 11, 2009, which is the National Stage of International Application No. PCT/SE2008/050613, filed May 23, 2008, which claims priority to Swedish Patent Application No. SE 0701488-9, filed Jun. 15, 2007, the disclosures of each of which are incorporated herein by reference in their entirety. TECHNICAL FIELD [0002] The invention is related to handling of data transmissions in a wireless communication network. More specifically, it is related to avoiding the discarding of successive data transmissions between a transmitter and a receiver in a wireless communication network. BACKGROUND [0003] In wireless communication networks of the latest generation and especially in HSDPA-based (High Speed Downlink Packet Access) wireless communication networks data sent from a base station towards one or more mobile terminals (UEs) may be scheduled for transmission on high-speed channels, such as the HS-DSCH (High Speed Downlink Shared Channel). [0004] Also, a UE in these networks may be in different states in a coverage area serviced by a base station, such as CELL_DCH, CELL_FACH, Enhanced CELL_FACH and other states known to the skilled person. [0005] In the CELL_DCH state, data transmitted on HS-DSCH is grouped into transport blocks (TBs) each of which among others comprises a transmission sequence number (TSN) in the header portion of the TB and the user data in the form of MAC-d PDUs (dedicated Media Access Control Packet Data Units) or MAC-c PDUs (common Media Access Control Packet Data Units) in the payload portion. Using a reordering queue as a buffer for transport blocks received and the TSN from the TB header plus control information sent on a control channel a UE can correctly order the TBs received from the base station and forward them to higher layers as MAC-d or MAC-c PDUs. To make the reordering of the TBs more efficient, each UE has a receiver window having a certain size into which TBs with their TSN are received and a timer (T1 timer) which prevents stalling of the TBs in the reordering queue if some TBs are not correctly received. [0006] After a TB is correctly received, the UE updates a parameter indicating the TSN for the next expected TB. [0007] This reordering mechanism for the TBs received at the UE is based on individual (TSNs) and T1 timers, see for example 3GPP TS 25.321. However, when transmitting data on the HS-DSCH using a common H-RNTI, it is not possible to maintain individual TSNs and T1 timers for individual UEs in the network. A single TSN and T1 timer in the network needs to be used for several UEs. [0008] Additionally, in an HSDPA-based wireless network, the Enhanced CELL_FACH state introduces the reception of data on the HS-DSCH in the CELL_FACH state and therefore potentially higher data rates. The reception of data in the HS-DSCH in CELL_FACH state is similar to the reception of data in the HS-DSCH in CELL_DCH state where some of the differences are stated below. [0009] A user equipment (UE) in the Enhanced CELL_FACH state receives retransmissions on HS-DSCH without sending Hybrid Automatic Repeat reQuest (HARQ) feedback signaling (ACK/NACK). Thus, the transport network does not know whether data has been correctly received or not, but rather retransmissions are decided blindly by the network. [0010] Also, the Enhanced CELL_FACH state offers the possibility to transmit data to UEs using a common HS-DSCH Radio Network Temporary Identifier (H-RNTI). An H-RNTI in an HSDPA network is simply a logical address of a UE in a coverage area of a base station. It is possible that more than one UE can share one common H-RNTI. This is needed for UEs that have entered the coverage area of the base station and in the initial HS-DSCH establishment phase do not have a dedicated H-RNTI assigned yet. [0011] Usually in the Enhanced CELL_FACH state the initial value of the next expected TSN is set to 0 in the UE and the discard window is set to [63-WINDOW_SIZE . . . 63], where WINDOW_SIZE refers to the side of the receiver window. The discard window can be defined as the part of the receiver window which is not accepted for re-ordering of TBs. [0012] Now, as the network is using a common TSN for all UEs using a common H-RNTI, there is a likelihood that the first TSN received by the UE is within the discard window. In this case the UE will discard the received transmission. [0013] One solution to this problem has been proposed in “Solution to reordering issue in Enhacned Cell_FACH”, 3GPP TSG-RAN WG2#57bis, Kobe, Japan, May 7-11, 2007. It consists of assigning a special initial value to the next expected TSN, and initializing the discard window based on the first received TSN. This solution avoids the problem of discarding initial transmission. However, during continuous reception, it is necessary for the UE to update the next expected TSN continuously in order to avoid discarding successive transmissions. This requires that all (or several) transmitted TSNs are received correctly by the UE. In practice the HS-SCCH is power controlled and it may be difficult for the UE to receive all TSNs. [0014] The present invention offers a solution to at least some of the problems associated with known technology. SUMMARY [0015] One aspect of the present invention is related to a method for managing communication at a mobile terminal, which may include receiving an initial transmission unit having a shared destination address and comprising an initial shared sequence number and a payload carrying data, determining that the initial transmission unit was correctly received, starting a timer associated with transmission units having a common destination address and a common sequence number, determining that the timer has expired, and resetting the value of sequence number for the next expected transmission unit and the upper boundary of a receiver window in the mobile terminal to a predefined initial value. [0016] In this fashion no initial TBs transmitted to a UE which is using shared destination address (such as a common H-RNTI in HSDPA networks), will be discarded by the UE. Especially during establishment of a radio channel for data transmission, where control data may be communicated on the shared destination address between a UE and a base station, data loss is prevented. [0017] Another aspect of the present invention is related to a mobile terminal for communication in a wireless communication network, where the mobile terminal may include a communication unit for receiving transmission units having a shared destination address and comprising a shared sequence number and payload carrying data, a processing unit configured for examining the transmission units received and determining whether they are correctly received, a measurement unit comprising a timer associated with transmission units having a shared destination address and a shared sequence number where the processing unit is further configured to instruct the measurement unit to start the timer when an initial transmission unit with a shared destination address and shared sequence number is correctly received, the processing unit being further configured to reset the sequence number for the next expected transmission unit and the upper boundary of its receiving window to a predefined initial value upon expiration of the timer. [0018] Yet another aspect of the present invention is related to an infrastructure node for communication in a wireless communication network, where the infrastructure node includes a processing unit configured for forming transmission units comprising a shared sequence number and a payload carrying data to be transmitted to a shared destination address, a communication unit for transmitting the transmission units to the shared destination address, a measurement unit comprising at least one timer associated with transmission units having a shared destination address and a shared sequence number and where the processing unit is configured to instruct the measurement unit to start the one or more timers upon transmission of an initial transmission unit to a shared destination address, the processing unit being further configured to reset the sequence number for the next expected transmission unit and the upper boundary for the transmission window to a predefined initial value upon expiration of the timer. [0019] Finally, another aspect of the present invention is related to a computer program for managing communication in a mobile terminal, which may include instruction sets for receiving an initial transmission unit having a shared destination address and comprising an initial shared sequence number and a payload carrying data, determining that the initial transmission unit was correctly received, starting a timer associated with transmission units having a common destination address and a common sequence number, determining that the timer has expired, and resetting the value of sequence number for the next expected transmission unit and the upper boundary of a receiver window in the mobile terminal to a predefined initial value. [0020] It may be mentioned that the infrastructure node in the wireless communication network may be a base station, a Node B, an access point or some other node with the functionality of the infrastructure node according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS [0021] In the following the invention will be described in a non-limiting way and in more detail with reference to exemplary embodiments illustrated in the enclosed drawings, in which: [0022] FIG. 1 illustrates schematically a flow chart depicting the steps of a method according to one embodiment of the present invention; [0023] FIG. 2 illustrates in the form of a block diagram a mobile terminal according to one embodiment of the present invention, [0024] FIG. 3 illustrates schematically in the form of a block diagram a base station according to one embodiment of the present invention; [0025] FIG. 4 illustrates schematically the signalling between a base station and a mobile terminal in a wireless communication network. DETAILED DESCRIPTION [0026] Before the embodiments of the present invention depicted in FIGS. 1-4 are described, some parameters and variables will be defined for better understanding: [0027] Parameter: Receiver window size (RECEIVE_WINDOW_SIZE): The RECEIVE_WINDOW_SIZE is the size of the receiver window according to the definition below. This is a parameter in the UE and the value of the parameter is configured by higher layers. [0029] State Variables: Next_expected_TSN (next_expected_TSN): The next_expected_TSN is the Transmission sequence number (TSN) following the TSN of the last in-sequence reordering PDU received. It may be updated according to the procedures given. The initial value of next_expected_TSN=0. Receiver window: The receiver window defines TSNs of those reordering PDUs that can be received in the receiver without causing an advancement of the receiver window according to the procedure below. The size of the receiver window equals RECEIVE_WINDOW_SIZE and spans TSNs going from RcvWindow_UpperEdge−RECEIVE_WINDOW_SIZE+1 to RcvWindow_UpperEdge included. RcvWindow_UpperEdge: The RcvWindow_UpperEdge represents the TSN, which is at the upper edge of the receiver window. After the first reordering PDU has been received successfully, it also corresponds to the reordering PDU with the highest TSN of all received reordering PDUs. The initial RcvWindow_UpperEdge equals 63. RcvWindow_UpperEdge is updated based on the reception of new reordering PDU according to the procedure given below. T1 TSN: The TSN of the latest MAC-ehs SDU that cannot be delivered to the reassembly entity, when the timer T1 is started. [0034] Preferably, all state variables are non-negative integers. Reordering PDUs are numbered by modulo integer Transmission sequence numbers (TSN) cycling through the field 0 to 63. All arithmetic operations, given as example, on next_expected_TSN, RcvWindow_UpperEdge, T1_TSN and TSN_flush are affected by the 64 modulus. When performing arithmetic comparisons of state variables or Transmission sequence number values a 64 modulus base may be used. This modulus base is subtracted (within the appropriate field) from all the values involved and then an absolute comparison is performed. RcvWindow_UpperEdge−RECEIVE_WINDOW_SIZE+1 may be assumed to be the modulus base. [0035] Timers: Re-ordering release timer (T1): The Re-ordering release timer T1 controls the stall avoidance in the UE reordering buffer as described below. The value of T1 is configured by upper layers. Reset timer (Treset) (FDD only): Treset controls the reset of the MAC-ehs reordering functionality when the common H-RNTI is used. [0038] Turning now to FIG. 1 , the method steps of the method according to one embodiment of the present invention seen from the perspective of a UE are shown. We assume for simplicity that the UE is operating in a coverage area for a base station which in turn has HSDPA functionality implemented. However, it should be pointed out that the method according to the present invention may be applied in any wireless communication network where mobile terminals in a coverage area of a base station or access point use a shared destination address for data received from the base station, where data is received in transmission blocks which are numbered, where the mobile terminals receive these transmission blocks during a certain receiver window and are able to order the transmission blocks in the right sequence by means of a reordering mechanism. Therefore, the focus on the HSDPA implementation below should only be regarded as a non-limiting illustrative example. [0039] Also, we assume that the UE has just entered the coverage area of the base station and does not have a dedicated destination address allocated, which in the case of the HSDPA network would be a dedicated H-RNTI, but rather has been allocated a common H-RNTI which it shares with other UEs present in the same coverage area. We also assume that the UE is in the CELL_FACH state, meaning that no HS-DSCH has yet been established between the UE and the base station. This is the starting point for the method steps 100 - 160 which will be described below. [0040] At step 100 , the UE initializes the next_expected_TSN parameter to an initial predefined value which may be 0 for example. Thereafter, the UE starts at step 110 receiving an initial TB intended for it on a common H-RNTI, where also each TB has a common TSN. TBs with a common TSN are delivered to the right individual UE by means of the Queue ID in the TB header, as is known to the skilled person. [0041] After the reception of the initial TB at the individual UE, the UE checks at step 120 whether the TB has been received correctly. This may be checked by methods such as CRC (Cyclic Redundancy Check) or other methods known to the skilled person and will not be elaborated here. [0042] In case the TB has not been correctly received, the UE stores at step 125 the received transport block and proceeds to receive either a retransmission or a new TB at step 110 again. Using HARQ for the HS-DSCH, the UE may then attempt to combine several transmission of the same TB in order to create a correct TB (step not shown in FIG. 1 ). In contrast to solutions suggested by known technology however, no initial TB intended for the UE which just entered the coverage area of the base station and which is correctly received is discarded if its common TSN lies outside of the UE's receiver window. As mentioned in the description of background art, this may happen if there is more than one UE involved each having their own receiver windows. Instead, at step 130 , if the UE has determined that the TB has been received correctly, it checks at step 140 whether a timer Treset has been started. If not, the UE starts the Treset timer at step 145 . Otherwise, if the Treset timer is already running it is restarted at step 150 . In this fashion, a first TB which is received at the UE, but which normally would be discarded if its common TSN would lie outside the receiver window of the UE, will be accepted by UE and therefore data loss will be prevented. Resetting an already running Treset time will ensure that only one Treset timer is active at a time. [0043] At step 155 the UE stores the correctly received TB in its reordering queue. Thereafter, the UE checks at step 160 whether the Treset timer has expired. If this is not the case, the UE returns to step 110 and continues receiving additional TBs. However, if the timer Treset has expired, the UE sets at step 170 the next_expected_TSN to an initial value again (such as to 0) and the RcvWindow_UpperEdge is set to its initial value as well. [0044] The reason for checking whether Treset has expired is that inactivity periods where no transmission blocks are sent can be detected and transport blocks with the right initial TSN expected by the UE can be received avoiding the loss of the initial transmission as is the case with some solutions suggested by known technology. [0045] The invention can be applied instead or in addition to the solution using a special value for the initial value of the next expected TSN. Moreover the Treset timer in the method illustrated in FIG. 1 may be used in any state where the UE is listening to transmissions on a downlink data or control radio channel where a shared destination address is used. [0046] It should be mentioned that the above described method steps are suitable to be implemented by a computer program comprising instructions sets running in an internal or external memory of the UE (not shown). [0047] FIG. 2 illustrates an UE 200 according to one embodiment of the present invention, where the UE 200 is equipped with a communication unit CMU, a memory MEM, a measurement unit MU, a processing unit CPU and a user interface UI. [0048] The communication unit CMU may be for example implemented as a receiver/transmitter combination adapted for communication in a wireless communication network, such as a UMTS, HSDPA, HSUPA, LTE or some other wireless communication network. Even though the description below focuses on the implementation of the UE in an HSDPA network, it should be borne in mind that the mobile terminal UE may also function in other wireless communication networks. [0049] Moreover, the memory MEM may comprise one or more reordering buffers, where transmission blocks are stored in case not all transmission blocks in sequence have yet been delivered, such that they can later be put in the right order before they are being sent to higher layers for disassembly into PDUs. This is known to the skilled person. [0050] Also, the memory MEM may be internal, external or a combination of the two, where in one part of the memory not comprising the reordering queues a computer program may be running which may comprise instruction sets adapted to execute the method steps described in FIG. 1 . [0051] Futhermore, the measurement unit MU may comprise at least two timers, of which the first one T1, is known to the skilled person, while the second Treset is part of the embodiment of the UE according to the present invention. The main task of the measurement unit is to start, restart and expire the timers mentioned above by receiving instructions from the processing unit CPU to do perform these operations. [0052] Since the function of the timer T1 is sufficiently known to the skilled person it will not be described further. The function of the Treset timer on the other hand is, as mentioned earlier, to prevent the discarding of initially transmitted transport blocks sent to a shared destination address, such as a common H-RNTI in the HSDPA implementation. [0053] The processing unit CPU of the UE 200 is adapted to manage functions which are known to the skilled person (such as the T1 timer in the measurement unit MU), but also to instruct the measurement unit to start and restart the Treset timer as well as to set the length Treset timer. Thus the UE 200 according to the present invention may avoid loss of initial transmissions during the establishment of the HS-DSCH when the UE 200 enters a coverage area services by a base station. The start of the Treset timer may by way of example be performed by sending a trigger signal to the measurement unit MU upon receiving transmission on a common H-RNTI (if the UE is operating in an HSDPA-network) and a upon determining that an initial TB has been correctly received. Correct reception of TBs may by way of example be implemented in the processing unit CPU by means of a CRC check, which is known to the skilled person. Those TBs which are correctly received but have a TSN higher than the next expected TSN may be placed by the processing unit CPU in the reordering buffer in the memory MEM for later in-sequence delivery to higher layers of the protocol stack. [0054] Additionally, the processing unit may instruct the measurement unit MU to restart the Treset timer if it by examining the state of the Treset timer detects that the latter is still active and that another TB has been correctly received. In this fashion it is ensured that only one Treset timer is active in one UE. [0055] Also, the processing unit CPU is adapted to initialize the next_expected_TSN variable to a predefined initial value, which for example may be 0 before instructing the measurement unit MU to start the Treset timer. [0056] As another function according to the embodiment of the present invention in FIG. 2 , the processing unit CPU may be adapted to check whether the Treset timer has expired and reset the next_expected_TSN to the predefined initial value as well as to set the Receiving_Window_UpperEdge to a predefined initial value. [0057] Finally, the UE 200 also comprises a user interface UI for facilitating interaction between a user of the UE 200 and the functions provided by the UE 200 which is well-known to the skilled person. [0058] FIG. 3 illustrates a base station 300 (or a communication gateway) according to one embodiment of the present invention. Even though an HSDPA implementation of the base station 300 is described below, it should be only regarded as an illustrative example. In fact, the base station 300 according to the present invention may be used in any wireless communication network as a Node B, base station transceiver, access point or an infrastructure node performing an analogous function in the network, where data is sent on control and data channels, where mobile terminals in the coverage area use one common destination address in the initial channel setup phase and where there is a risk of losing an initial transmission of a transport block due to it being located outside a receiver window of the one or more UEs. Hence, the base station may be active in such networks as HSDPA, HSUPA (High Speed Uplink Packer Access), 3GPP LTE (Third Generation Partnership Project Long Term Evolution) as well as in other wireless communication networks The base station comprises a communication unit CMU, a processing unit CPU, a memory MEM and a measurement unit MU. [0059] Similar to the function of the communication unit of the UE in FIG. 2 , the communication unit CMU comprises a receiver/transmitter combination for receiving and transmitting data from and to one or more UEs which are located in the coverage area of the base station 300 . Also, the communication unit CMU is adapted for receiving and transmitting data from and to an RNC (Radio Network Controller). [0060] The processing unit CPU of the base station 300 is adapted for receiving data intended for UEs and storing it into buffers of the memory MEM. In the HSDPA implementation these buffers may have the function of priority queues. Another function of the processing unit CPU is to retrieve data stored from one or more buffers in the memory MEM and to assemble it into transport blocks. As is known to the skilled person, the processing unit CPU may add a TSN into the header portion of such a transport block and attach one or more PDUs containing user or control data into the payload portion of these transport blocks. [0061] Furthermore, the measurement unit MU according to the present invention may comprise one or more Treset timers, where each Treset timer is specific for one UE which is located in the coverage area of the base station 300 . Each time the base station 300 registers a new UE entering its coverage area not having a dedicated destination address for control data (such as a dedicated H-RNTI in the HSDPA implementation), the processing unit CPU is adapted to initialize the next_expected_TSN to a predefined initial value and to transmit control data on a shared destination address (for example a common H-RNTI) leading to the establishment of a high-speed downlink channel. At the same time the processing unit CPU instructs the measurement unit MU to start the Treset timer at the start of the transmission of control data to a common destination address and to increment the next_expected_TSN value by 1. As is known to the skilled person, the processing unit CPU may also initiate retransmissions of transport blocks which in this case will have a TSN value different from the next_expected_TSN value. [0062] After the processing unit CPU has detected that the Treset timer in the measurement unit MU has expired the processing unit CPU is adapted to instruct the measurement unit to restart the Treset timer, the next_expected_TSN and the transmission window. In this fashion, after a period of inactivity, the base station 300 can start sending data again without causing initial data loss for UEs that newly entered it's the coverage area of the base station 300 , which would be the case if the next_expected_TSN was simply incremented further. [0063] Turning now to FIG. 4 an example communication flow between UE and a Node B is schematically represented. [0064] Both the UE and the network implement a reset timer, T_reset. The timer is started (or restarted if it was already running) after each transmission using a common H-RNTI, and upon expiring the network and the UE both will set the next_expected_TSN and the window to their initial values (0 or special initial value for TSN). [0065] In the Node B there is one reset timer for each common H-RNTI, where these timers may operate independently. In contrast, in the UE there may be only one reset timer, since the UE may be adapted to only receive data from the Node B using one common H-RNTI at a time. [0066] The above mentioned and described embodiments are only given as examples and should not be limiting to the present invention. Other solutions, uses, objectives, and functions within the scope of the invention as claimed in the below described patent claims should be apparent for the person skilled in the art.
The invention relates to a method and device in a communications network when a User Equipment, UE, needs to update a next expected Transmission Sequence Number, TSN, continuously in order to avoid discarding successive transmissions. The method comprises: resetting a next expected TSN value in said network and UE to predetermined values after a predetermined inactivity time.
Condense the core contents of the given document.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser.", "No. 12/664,373, filed Dec. 11, 2009, which is the National Stage of International Application No. PCT/SE2008/050613, filed May 23, 2008, which claims priority to Swedish Patent Application No. SE 0701488-9, filed Jun. 15, 2007, the disclosures of each of which are incorporated herein by reference in their entirety.", "TECHNICAL FIELD [0002] The invention is related to handling of data transmissions in a wireless communication network.", "More specifically, it is related to avoiding the discarding of successive data transmissions between a transmitter and a receiver in a wireless communication network.", "BACKGROUND [0003] In wireless communication networks of the latest generation and especially in HSDPA-based (High Speed Downlink Packet Access) wireless communication networks data sent from a base station towards one or more mobile terminals (UEs) may be scheduled for transmission on high-speed channels, such as the HS-DSCH (High Speed Downlink Shared Channel).", "[0004] Also, a UE in these networks may be in different states in a coverage area serviced by a base station, such as CELL_DCH, CELL_FACH, Enhanced CELL_FACH and other states known to the skilled person.", "[0005] In the CELL_DCH state, data transmitted on HS-DSCH is grouped into transport blocks (TBs) each of which among others comprises a transmission sequence number (TSN) in the header portion of the TB and the user data in the form of MAC-d PDUs (dedicated Media Access Control Packet Data Units) or MAC-c PDUs (common Media Access Control Packet Data Units) in the payload portion.", "Using a reordering queue as a buffer for transport blocks received and the TSN from the TB header plus control information sent on a control channel a UE can correctly order the TBs received from the base station and forward them to higher layers as MAC-d or MAC-c PDUs.", "To make the reordering of the TBs more efficient, each UE has a receiver window having a certain size into which TBs with their TSN are received and a timer (T1 timer) which prevents stalling of the TBs in the reordering queue if some TBs are not correctly received.", "[0006] After a TB is correctly received, the UE updates a parameter indicating the TSN for the next expected TB.", "[0007] This reordering mechanism for the TBs received at the UE is based on individual (TSNs) and T1 timers, see for example 3GPP TS 25.321.", "However, when transmitting data on the HS-DSCH using a common H-RNTI, it is not possible to maintain individual TSNs and T1 timers for individual UEs in the network.", "A single TSN and T1 timer in the network needs to be used for several UEs.", "[0008] Additionally, in an HSDPA-based wireless network, the Enhanced CELL_FACH state introduces the reception of data on the HS-DSCH in the CELL_FACH state and therefore potentially higher data rates.", "The reception of data in the HS-DSCH in CELL_FACH state is similar to the reception of data in the HS-DSCH in CELL_DCH state where some of the differences are stated below.", "[0009] A user equipment (UE) in the Enhanced CELL_FACH state receives retransmissions on HS-DSCH without sending Hybrid Automatic Repeat reQuest (HARQ) feedback signaling (ACK/NACK).", "Thus, the transport network does not know whether data has been correctly received or not, but rather retransmissions are decided blindly by the network.", "[0010] Also, the Enhanced CELL_FACH state offers the possibility to transmit data to UEs using a common HS-DSCH Radio Network Temporary Identifier (H-RNTI).", "An H-RNTI in an HSDPA network is simply a logical address of a UE in a coverage area of a base station.", "It is possible that more than one UE can share one common H-RNTI.", "This is needed for UEs that have entered the coverage area of the base station and in the initial HS-DSCH establishment phase do not have a dedicated H-RNTI assigned yet.", "[0011] Usually in the Enhanced CELL_FACH state the initial value of the next expected TSN is set to 0 in the UE and the discard window is set to [63-WINDOW_SIZE .", "63], where WINDOW_SIZE refers to the side of the receiver window.", "The discard window can be defined as the part of the receiver window which is not accepted for re-ordering of TBs.", "[0012] Now, as the network is using a common TSN for all UEs using a common H-RNTI, there is a likelihood that the first TSN received by the UE is within the discard window.", "In this case the UE will discard the received transmission.", "[0013] One solution to this problem has been proposed in “Solution to reordering issue in Enhacned Cell_FACH”, 3GPP TSG-RAN WG2#57bis, Kobe, Japan, May 7-11, 2007.", "It consists of assigning a special initial value to the next expected TSN, and initializing the discard window based on the first received TSN.", "This solution avoids the problem of discarding initial transmission.", "However, during continuous reception, it is necessary for the UE to update the next expected TSN continuously in order to avoid discarding successive transmissions.", "This requires that all (or several) transmitted TSNs are received correctly by the UE.", "In practice the HS-SCCH is power controlled and it may be difficult for the UE to receive all TSNs.", "[0014] The present invention offers a solution to at least some of the problems associated with known technology.", "SUMMARY [0015] One aspect of the present invention is related to a method for managing communication at a mobile terminal, which may include receiving an initial transmission unit having a shared destination address and comprising an initial shared sequence number and a payload carrying data, determining that the initial transmission unit was correctly received, starting a timer associated with transmission units having a common destination address and a common sequence number, determining that the timer has expired, and resetting the value of sequence number for the next expected transmission unit and the upper boundary of a receiver window in the mobile terminal to a predefined initial value.", "[0016] In this fashion no initial TBs transmitted to a UE which is using shared destination address (such as a common H-RNTI in HSDPA networks), will be discarded by the UE.", "Especially during establishment of a radio channel for data transmission, where control data may be communicated on the shared destination address between a UE and a base station, data loss is prevented.", "[0017] Another aspect of the present invention is related to a mobile terminal for communication in a wireless communication network, where the mobile terminal may include a communication unit for receiving transmission units having a shared destination address and comprising a shared sequence number and payload carrying data, a processing unit configured for examining the transmission units received and determining whether they are correctly received, a measurement unit comprising a timer associated with transmission units having a shared destination address and a shared sequence number where the processing unit is further configured to instruct the measurement unit to start the timer when an initial transmission unit with a shared destination address and shared sequence number is correctly received, the processing unit being further configured to reset the sequence number for the next expected transmission unit and the upper boundary of its receiving window to a predefined initial value upon expiration of the timer.", "[0018] Yet another aspect of the present invention is related to an infrastructure node for communication in a wireless communication network, where the infrastructure node includes a processing unit configured for forming transmission units comprising a shared sequence number and a payload carrying data to be transmitted to a shared destination address, a communication unit for transmitting the transmission units to the shared destination address, a measurement unit comprising at least one timer associated with transmission units having a shared destination address and a shared sequence number and where the processing unit is configured to instruct the measurement unit to start the one or more timers upon transmission of an initial transmission unit to a shared destination address, the processing unit being further configured to reset the sequence number for the next expected transmission unit and the upper boundary for the transmission window to a predefined initial value upon expiration of the timer.", "[0019] Finally, another aspect of the present invention is related to a computer program for managing communication in a mobile terminal, which may include instruction sets for receiving an initial transmission unit having a shared destination address and comprising an initial shared sequence number and a payload carrying data, determining that the initial transmission unit was correctly received, starting a timer associated with transmission units having a common destination address and a common sequence number, determining that the timer has expired, and resetting the value of sequence number for the next expected transmission unit and the upper boundary of a receiver window in the mobile terminal to a predefined initial value.", "[0020] It may be mentioned that the infrastructure node in the wireless communication network may be a base station, a Node B, an access point or some other node with the functionality of the infrastructure node according to the present invention.", "BRIEF DESCRIPTION OF THE DRAWINGS [0021] In the following the invention will be described in a non-limiting way and in more detail with reference to exemplary embodiments illustrated in the enclosed drawings, in which: [0022] FIG. 1 illustrates schematically a flow chart depicting the steps of a method according to one embodiment of the present invention;", "[0023] FIG. 2 illustrates in the form of a block diagram a mobile terminal according to one embodiment of the present invention, [0024] FIG. 3 illustrates schematically in the form of a block diagram a base station according to one embodiment of the present invention;", "[0025] FIG. 4 illustrates schematically the signalling between a base station and a mobile terminal in a wireless communication network.", "DETAILED DESCRIPTION [0026] Before the embodiments of the present invention depicted in FIGS. 1-4 are described, some parameters and variables will be defined for better understanding: [0027] Parameter: Receiver window size (RECEIVE_WINDOW_SIZE): The RECEIVE_WINDOW_SIZE is the size of the receiver window according to the definition below.", "This is a parameter in the UE and the value of the parameter is configured by higher layers.", "[0029] State Variables: Next_expected_TSN (next_expected_TSN): The next_expected_TSN is the Transmission sequence number (TSN) following the TSN of the last in-sequence reordering PDU received.", "It may be updated according to the procedures given.", "The initial value of next_expected_TSN=0.", "Receiver window: The receiver window defines TSNs of those reordering PDUs that can be received in the receiver without causing an advancement of the receiver window according to the procedure below.", "The size of the receiver window equals RECEIVE_WINDOW_SIZE and spans TSNs going from RcvWindow_UpperEdge−RECEIVE_WINDOW_SIZE+1 to RcvWindow_UpperEdge included.", "RcvWindow_UpperEdge: The RcvWindow_UpperEdge represents the TSN, which is at the upper edge of the receiver window.", "After the first reordering PDU has been received successfully, it also corresponds to the reordering PDU with the highest TSN of all received reordering PDUs.", "The initial RcvWindow_UpperEdge equals 63.", "RcvWindow_UpperEdge is updated based on the reception of new reordering PDU according to the procedure given below.", "T1 TSN: The TSN of the latest MAC-ehs SDU that cannot be delivered to the reassembly entity, when the timer T1 is started.", "[0034] Preferably, all state variables are non-negative integers.", "Reordering PDUs are numbered by modulo integer Transmission sequence numbers (TSN) cycling through the field 0 to 63.", "All arithmetic operations, given as example, on next_expected_TSN, RcvWindow_UpperEdge, T1_TSN and TSN_flush are affected by the 64 modulus.", "When performing arithmetic comparisons of state variables or Transmission sequence number values a 64 modulus base may be used.", "This modulus base is subtracted (within the appropriate field) from all the values involved and then an absolute comparison is performed.", "RcvWindow_UpperEdge−RECEIVE_WINDOW_SIZE+1 may be assumed to be the modulus base.", "[0035] Timers: Re-ordering release timer (T1): The Re-ordering release timer T1 controls the stall avoidance in the UE reordering buffer as described below.", "The value of T1 is configured by upper layers.", "Reset timer (Treset) (FDD only): Treset controls the reset of the MAC-ehs reordering functionality when the common H-RNTI is used.", "[0038] Turning now to FIG. 1 , the method steps of the method according to one embodiment of the present invention seen from the perspective of a UE are shown.", "We assume for simplicity that the UE is operating in a coverage area for a base station which in turn has HSDPA functionality implemented.", "However, it should be pointed out that the method according to the present invention may be applied in any wireless communication network where mobile terminals in a coverage area of a base station or access point use a shared destination address for data received from the base station, where data is received in transmission blocks which are numbered, where the mobile terminals receive these transmission blocks during a certain receiver window and are able to order the transmission blocks in the right sequence by means of a reordering mechanism.", "Therefore, the focus on the HSDPA implementation below should only be regarded as a non-limiting illustrative example.", "[0039] Also, we assume that the UE has just entered the coverage area of the base station and does not have a dedicated destination address allocated, which in the case of the HSDPA network would be a dedicated H-RNTI, but rather has been allocated a common H-RNTI which it shares with other UEs present in the same coverage area.", "We also assume that the UE is in the CELL_FACH state, meaning that no HS-DSCH has yet been established between the UE and the base station.", "This is the starting point for the method steps 100 - 160 which will be described below.", "[0040] At step 100 , the UE initializes the next_expected_TSN parameter to an initial predefined value which may be 0 for example.", "Thereafter, the UE starts at step 110 receiving an initial TB intended for it on a common H-RNTI, where also each TB has a common TSN.", "TBs with a common TSN are delivered to the right individual UE by means of the Queue ID in the TB header, as is known to the skilled person.", "[0041] After the reception of the initial TB at the individual UE, the UE checks at step 120 whether the TB has been received correctly.", "This may be checked by methods such as CRC (Cyclic Redundancy Check) or other methods known to the skilled person and will not be elaborated here.", "[0042] In case the TB has not been correctly received, the UE stores at step 125 the received transport block and proceeds to receive either a retransmission or a new TB at step 110 again.", "Using HARQ for the HS-DSCH, the UE may then attempt to combine several transmission of the same TB in order to create a correct TB (step not shown in FIG. 1 ).", "In contrast to solutions suggested by known technology however, no initial TB intended for the UE which just entered the coverage area of the base station and which is correctly received is discarded if its common TSN lies outside of the UE's receiver window.", "As mentioned in the description of background art, this may happen if there is more than one UE involved each having their own receiver windows.", "Instead, at step 130 , if the UE has determined that the TB has been received correctly, it checks at step 140 whether a timer Treset has been started.", "If not, the UE starts the Treset timer at step 145 .", "Otherwise, if the Treset timer is already running it is restarted at step 150 .", "In this fashion, a first TB which is received at the UE, but which normally would be discarded if its common TSN would lie outside the receiver window of the UE, will be accepted by UE and therefore data loss will be prevented.", "Resetting an already running Treset time will ensure that only one Treset timer is active at a time.", "[0043] At step 155 the UE stores the correctly received TB in its reordering queue.", "Thereafter, the UE checks at step 160 whether the Treset timer has expired.", "If this is not the case, the UE returns to step 110 and continues receiving additional TBs.", "However, if the timer Treset has expired, the UE sets at step 170 the next_expected_TSN to an initial value again (such as to 0) and the RcvWindow_UpperEdge is set to its initial value as well.", "[0044] The reason for checking whether Treset has expired is that inactivity periods where no transmission blocks are sent can be detected and transport blocks with the right initial TSN expected by the UE can be received avoiding the loss of the initial transmission as is the case with some solutions suggested by known technology.", "[0045] The invention can be applied instead or in addition to the solution using a special value for the initial value of the next expected TSN.", "Moreover the Treset timer in the method illustrated in FIG. 1 may be used in any state where the UE is listening to transmissions on a downlink data or control radio channel where a shared destination address is used.", "[0046] It should be mentioned that the above described method steps are suitable to be implemented by a computer program comprising instructions sets running in an internal or external memory of the UE (not shown).", "[0047] FIG. 2 illustrates an UE 200 according to one embodiment of the present invention, where the UE 200 is equipped with a communication unit CMU, a memory MEM, a measurement unit MU, a processing unit CPU and a user interface UI.", "[0048] The communication unit CMU may be for example implemented as a receiver/transmitter combination adapted for communication in a wireless communication network, such as a UMTS, HSDPA, HSUPA, LTE or some other wireless communication network.", "Even though the description below focuses on the implementation of the UE in an HSDPA network, it should be borne in mind that the mobile terminal UE may also function in other wireless communication networks.", "[0049] Moreover, the memory MEM may comprise one or more reordering buffers, where transmission blocks are stored in case not all transmission blocks in sequence have yet been delivered, such that they can later be put in the right order before they are being sent to higher layers for disassembly into PDUs.", "This is known to the skilled person.", "[0050] Also, the memory MEM may be internal, external or a combination of the two, where in one part of the memory not comprising the reordering queues a computer program may be running which may comprise instruction sets adapted to execute the method steps described in FIG. 1 .", "[0051] Futhermore, the measurement unit MU may comprise at least two timers, of which the first one T1, is known to the skilled person, while the second Treset is part of the embodiment of the UE according to the present invention.", "The main task of the measurement unit is to start, restart and expire the timers mentioned above by receiving instructions from the processing unit CPU to do perform these operations.", "[0052] Since the function of the timer T1 is sufficiently known to the skilled person it will not be described further.", "The function of the Treset timer on the other hand is, as mentioned earlier, to prevent the discarding of initially transmitted transport blocks sent to a shared destination address, such as a common H-RNTI in the HSDPA implementation.", "[0053] The processing unit CPU of the UE 200 is adapted to manage functions which are known to the skilled person (such as the T1 timer in the measurement unit MU), but also to instruct the measurement unit to start and restart the Treset timer as well as to set the length Treset timer.", "Thus the UE 200 according to the present invention may avoid loss of initial transmissions during the establishment of the HS-DSCH when the UE 200 enters a coverage area services by a base station.", "The start of the Treset timer may by way of example be performed by sending a trigger signal to the measurement unit MU upon receiving transmission on a common H-RNTI (if the UE is operating in an HSDPA-network) and a upon determining that an initial TB has been correctly received.", "Correct reception of TBs may by way of example be implemented in the processing unit CPU by means of a CRC check, which is known to the skilled person.", "Those TBs which are correctly received but have a TSN higher than the next expected TSN may be placed by the processing unit CPU in the reordering buffer in the memory MEM for later in-sequence delivery to higher layers of the protocol stack.", "[0054] Additionally, the processing unit may instruct the measurement unit MU to restart the Treset timer if it by examining the state of the Treset timer detects that the latter is still active and that another TB has been correctly received.", "In this fashion it is ensured that only one Treset timer is active in one UE.", "[0055] Also, the processing unit CPU is adapted to initialize the next_expected_TSN variable to a predefined initial value, which for example may be 0 before instructing the measurement unit MU to start the Treset timer.", "[0056] As another function according to the embodiment of the present invention in FIG. 2 , the processing unit CPU may be adapted to check whether the Treset timer has expired and reset the next_expected_TSN to the predefined initial value as well as to set the Receiving_Window_UpperEdge to a predefined initial value.", "[0057] Finally, the UE 200 also comprises a user interface UI for facilitating interaction between a user of the UE 200 and the functions provided by the UE 200 which is well-known to the skilled person.", "[0058] FIG. 3 illustrates a base station 300 (or a communication gateway) according to one embodiment of the present invention.", "Even though an HSDPA implementation of the base station 300 is described below, it should be only regarded as an illustrative example.", "In fact, the base station 300 according to the present invention may be used in any wireless communication network as a Node B, base station transceiver, access point or an infrastructure node performing an analogous function in the network, where data is sent on control and data channels, where mobile terminals in the coverage area use one common destination address in the initial channel setup phase and where there is a risk of losing an initial transmission of a transport block due to it being located outside a receiver window of the one or more UEs.", "Hence, the base station may be active in such networks as HSDPA, HSUPA (High Speed Uplink Packer Access), 3GPP LTE (Third Generation Partnership Project Long Term Evolution) as well as in other wireless communication networks The base station comprises a communication unit CMU, a processing unit CPU, a memory MEM and a measurement unit MU.", "[0059] Similar to the function of the communication unit of the UE in FIG. 2 , the communication unit CMU comprises a receiver/transmitter combination for receiving and transmitting data from and to one or more UEs which are located in the coverage area of the base station 300 .", "Also, the communication unit CMU is adapted for receiving and transmitting data from and to an RNC (Radio Network Controller).", "[0060] The processing unit CPU of the base station 300 is adapted for receiving data intended for UEs and storing it into buffers of the memory MEM.", "In the HSDPA implementation these buffers may have the function of priority queues.", "Another function of the processing unit CPU is to retrieve data stored from one or more buffers in the memory MEM and to assemble it into transport blocks.", "As is known to the skilled person, the processing unit CPU may add a TSN into the header portion of such a transport block and attach one or more PDUs containing user or control data into the payload portion of these transport blocks.", "[0061] Furthermore, the measurement unit MU according to the present invention may comprise one or more Treset timers, where each Treset timer is specific for one UE which is located in the coverage area of the base station 300 .", "Each time the base station 300 registers a new UE entering its coverage area not having a dedicated destination address for control data (such as a dedicated H-RNTI in the HSDPA implementation), the processing unit CPU is adapted to initialize the next_expected_TSN to a predefined initial value and to transmit control data on a shared destination address (for example a common H-RNTI) leading to the establishment of a high-speed downlink channel.", "At the same time the processing unit CPU instructs the measurement unit MU to start the Treset timer at the start of the transmission of control data to a common destination address and to increment the next_expected_TSN value by 1.", "As is known to the skilled person, the processing unit CPU may also initiate retransmissions of transport blocks which in this case will have a TSN value different from the next_expected_TSN value.", "[0062] After the processing unit CPU has detected that the Treset timer in the measurement unit MU has expired the processing unit CPU is adapted to instruct the measurement unit to restart the Treset timer, the next_expected_TSN and the transmission window.", "In this fashion, after a period of inactivity, the base station 300 can start sending data again without causing initial data loss for UEs that newly entered it's the coverage area of the base station 300 , which would be the case if the next_expected_TSN was simply incremented further.", "[0063] Turning now to FIG. 4 an example communication flow between UE and a Node B is schematically represented.", "[0064] Both the UE and the network implement a reset timer, T_reset.", "The timer is started (or restarted if it was already running) after each transmission using a common H-RNTI, and upon expiring the network and the UE both will set the next_expected_TSN and the window to their initial values (0 or special initial value for TSN).", "[0065] In the Node B there is one reset timer for each common H-RNTI, where these timers may operate independently.", "In contrast, in the UE there may be only one reset timer, since the UE may be adapted to only receive data from the Node B using one common H-RNTI at a time.", "[0066] The above mentioned and described embodiments are only given as examples and should not be limiting to the present invention.", "Other solutions, uses, objectives, and functions within the scope of the invention as claimed in the below described patent claims should be apparent for the person skilled in the art." ]
CROSS REFERENCE TO RELATED APPLICATIONS This is a continuation-in-part of application Ser. No. 090,308, filed Nov. 1, 1979 now abandoned, which in turn is a continuation-in-part of application Ser. No. 28,800, filed Apr. 10, 1979 now abandoned. FIELD OF THE INVENTION This invention relates to periandrins which are novel natural sweet-tasting substances. The plants of the genus Periandra are the leguminous shrubs which grow wild in the northern and middle parts of Brazil. In these native localities, the roots of these plants are called "Alcacus de terra," which means "native licorice" in English, and have been used from ancient times for medical use and the like for purposes such as expectoration. The roots of these plants possess sweetness as well as a considerable degree of bitterness. Thus, the extracts obtained by extracting the above-mentioned roots with water, an alcohol, etc. could not be used, as they are, for sweeteners or sweetener aids such as licorice extracts. Incidentally, it has been reported that the sweet-taste component present in the roots of the Periandra plants is glycyrrhizin (Chemical Abstracts Vol. 36, p. 3319, 1942). SUMMARY OF THE INVENTION The present inventors have undertaken intensive research on the sweet-tasting substances contained in the roots of Periandra plants and have succeeded in isolating the sweet substances of the following four species, which have been named Periandrins I, II, III and IV, repectively. The periandrins provided by the present invention are represented by the following formula (A), wherein the substituent R is given in the following description and each M which is in the sugar moiety and which is also found in the moiety R is hydrogen or a cation substantially non-toxic to humans. ##STR1## The Periandrin I is a substance in which the substituent R in the formula (A) is represented by the following formula. ##STR2## The Periandrin II is a substance in which the R in the formula (A) is represented by the following formula. ##STR3## The Periandrin III is a substance in which the R in the formula (A) is represented by the following formula. ##STR4## The Periandrin IV is a substance in which the R in the formula (A) is represented by the following formula ##STR5## BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: FIGS. 1 through 4 are spectral diagrams respectively indicating the infrared absorption spectra of Periandrins I through IV. The samples of Periandrins I and II are in the free-acid form, and the samples of Periandrins III and IV are in the mono-ammonium salt form. DETAILED DESCRIPTION OF THE INVENTION Chemical structures and physical and chemical properties of Periandrins I, II, III and IV The periandrins provided in accordance with the present invention are glycosides represented by the following formula, wherein there are four Periandrins I through IV with respect to the substituent R. ##STR6## In the formula (A), each M which is in the sugar moiety and which is also found in the moiety R as shown hereinbelow is hydrogen or a cation substantially non-toxic to humans such as a monovalent cation such as an alkali metal, e.g., Na and K, or ammonium or calcium. ##STR7## Periandrin I in its free-acid form (M═H) has the following physical and chemical properties. (a) Melting point: >300° C. (turning black in the vicinity of 190° C.) (b) Specific rotation: [α] D 20 -23.0° (C=1.0, water) (c) Molecular weight: 822 (FD mass spectrometric analysis, M + .H.Na=846) (d) Elemental analysis: C 42 H 62 O 16 .4H 2 O Found: C 56.52%, H 7.61%. Calculated: C 56.36%, H 7.88%. (e) Compositional formula: C 42 H 62 O 16 (f) Infrared absorption spectrum: ν max KBr 3400, 3200, 1700, 1600, 1400, 1100, 625 cm -1 (cf. FIG. 1) (g) Solubilities: very soluble in water; soluble in pyridine; slightly soluble in methanol and ethanol (h) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonia water=4-3-2-3 Rf value 0.18 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.44 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.17 (i) Ultraviolet absorption spectrum: endabsorption (j) Appearance: colorless rectangular plate crystals (water-methanol mixed solvent) Periandrin II Periandrin II is a substance represented by the following formula, in which M has been defined hereinbefore. ##STR8## Periandrin II in its free-acid form (M═H) has the following physical and chemical properties. (a) Melting point: 216° to 220° C. (decomposed) (b) Specific rotation: [α] D 28 +37.0° C. (C=0.27, water) (c) Elemental analysis: C 42 H 62 O 16 .3H 2 O Found: C, 57.93% H, 7.80%. Calculated: C, 57.52% H, 7.82%. (d) Compositional formula: C 42 H 62 O 16 (e) Infrared absorption spectrum: ν max KBr 3400, 3200, 2950, 1710, 1600, 1400, 1060 cm -1 (cf. FIG. 2) (f) Solubilities: very soluble in water; soluble in pyridine; slightly soluble in methanol and ethanol. (g) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonia water=4-3-2-3 Rf value 0.18 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.44 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.21 (h) Ultraviolet absorption spectrum: endabsorption (i) Appearance: colorless rectangular plate crystals (water-methanol mixed solvent) Periandrin III Periandrin III is a substance represented by the following formula, in which M has been defined hereinbefore. ##STR9## Periandrin III in its free-acid form (M═H) has the following physical and chemical properties. (a) Melting point: >300° C. (b) Specific rotation: [α] D 18 -24.5° (C=1.1, water) (c) Elemental analysis: C 42 H 64 O 16 .2H 2 O Found: C 58.07%, H 8.17%. Calculated: C 58.59%, H 7.96%. (d) Compositional formula: C 42 H 64 O 16 (e) Infrared absorption spectrum: ν max KBr (the mono-ammonium salt) 3400, 2930, 1700, 1600 1408, 1040 cm -1 (cf. FIG. 3) (f) Solubilities: very soluble in water; soluble in pyridine; slightly soluble in methanol and ethanol (g) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonia water=4-3-2-3 Rf value 0.15 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.40 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.14 (h) Ultraviolet absorption spectrum: endabsorption (i) Appearance: colorless crystalline powder Periandrin IV Periandrin IV is a substance represented by the following formula, in which M has been defined hereinbefore. ##STR10## Periandrin IV in its free-acid form (M═H) has the following physical and chemical properties. (a) Melting point: >300° C. (b) Specific rotation: [α] D 22 +96° (C=2.5, water) (c) Elemental analysis: C 42 H 64 O 16 .3H 2 O Found: C 57.01%, H 7.70%. Calculated: C 57.39%, H 8.03%. (d) Compositional formula: C 42 H 64 O 16 (e) Infrared absorption spectrum: ν max KBr (the mono-ammonium salt) 3400, 2920, 1700, 1600 1407, 1045 cm -1 (cf. FIG. 4) (f) Solubilities: very soluble in water; soluble in pyridine; slightly soluble in methanol and ethanol (g) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonium water=4-3-2-3 Rf value 0.15 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.40 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.19 (h) Ultraviolet absorption spectrum: endabsorption (i) Appearance: colorless crystalline powder Extraction and purification of periandrins Periandrins are present in the roots of the plants of the genus Periandra, which are typically represented by Periandra mediteranea, Periandra dulcis, etc. The roots of these plants or these roots in dried state are subjected to extraction of the periandrins, if desired, after they have been chipped or ground. The extraction is generally carried out by employing, as an extracting reagent, (i) water or a water-hydrophilic or water-miscible organic solvent containing not more than about 80% of a hydrophilic or water miscible organic solvent (such as methanol, ethanol, propanol, butanol, acetone, and methyl ethyl ketone) under the condition of a pH not lower than 3, or (ii) a water-containing or aqueous hydrophilic organic solvent (such as ethanol containing not more than 15% of water) under an acidic condition of a pH lower than 3. The temperature for the extraction is not especially restricted, and can be in the range of higher than the freezing point of the extracting reagent and lower than its boiling point. Under the condition of a low temperature, there is an advantage in that the resulting extract is accompanied by a smaller amount of impurities although a longer time is required for leaching. Under the condition of a high temperature, the period of time for the extraction is advantageously shortened. The period of time for extraction can be optionally selected in accordance with the type of extracting reagent, temperature for extraction and other conditions. The efficiency of extraction can be increased by incorporating alkalis, polyphosphates and/or surface active agents into the extracting reagent. The isolation and purification of periandrins from the resulting extract can be carried out by combining suitably conventional purification methods such as (a) an acid precipitation method, (b) a method of extraction with water-containing or aqueous acidic hydrophilic or water-miscible organic solvents of a pH lower than 3, (c) a precipitation method using hydrophilic or water-miscible organic solvents of a pH not lower than 3, (d) a method of fractionation by ion-exchange or adsorption chromatography, (e) a method of treatment with molecular sieve membrane or dialysis membrane, and (f) a recrystallization method. The outlines of the typical purification methods are given below. Periandrins are precipitated from their aqueous solution systems under acidic conditions of a pH lower than 3. In this case, the major parts of the bitter substance contaminating the extract remain in the solution as they are. When mineral acids such as hydrochloric acid and sulfuric acid are added to the aqueous solution which has been directly prepared from the extract to carry out acid-precipitation treatment, periandrins are precipitated together with proteins and various acid-insoluble substances. In order to reduce the coprecipitation of proteins and the like, it is also possible to resort, depending on the necessity, to pretreatment steps such as (i) a method of decomposing the acid-insoluble substances such as proteins into acid-soluble peptides or amino acids according to a treatment with enzymes such as protease, (ii) a method of heating the proteins at a temperature of 70° C. or higher to coagulate and remove them, and (iii) a method of adding to the solution metal hydroxides such as calcium hydroxide, magnesium hydroxide and aluminium hydroxide or first adding to the solution inorganic salts of these metals and then adjusting the solution to an alkaline pH to form a metal hydroxide in the solution whereby proteins are precipitated and removed. In the case of the acid precipitation treatment, the yield of precipitate may be increased by the salt-out effect in the presence of neutral salts such as sodium chloride, sodium sulfate, sodium nitrate, sodium formate and sodium acetate. Under the pH conditions in the range of weak acidity of a pH of 3 or higher to alkalinity, the solubility of periandrins with respect to a solution containing about 85% or more hydrophilic or water miscible organic solvents is low, but the bitter substances are soluble therein, whereby the periandrins and bitter-taste substances can be separated. Thus, a periandrin can be separated and collected as a precipitate by adding a hydrophilic or water-miscible organic solvent in an amount such as 85% or more, preferably 95% or more, to the aqueous extract, the concentrated solution or solid of the separated and purified extract solution, or the solution prepared by neutralizing and dissolving the precipitate of the above-mentioned acid precipitation step. A periandrin can also be obtained as a precipitate from the extract obtained according to the extracting method with water-containing hydrophilic organic solvents of a pH lower than 3, by simply adjusting the pH of the extract to 3 or higher with alkalis. Since a periandrin is soluble at a pH lower than 3 in water-containing (or aqueous) hydrophilic (or water-miscible) organic solvents such as an aqueous ethanol, the aqueous extract is concentrated and adjusted to an acidic pH or the precipitate formed by the above-mentioned acid precipitation treatment is collected and, if necessary, adjusted to an acidic pH, and then hydrophilic organic solvent is added thereto in such an amount as to cause the concentration to be 85% or higher, preferably 95% or higher. Periandrins can be thus extracted. As a method of preparing an aqueous solution of a periandrin from the resulting extract, insoluble residues are removed from the extract and (1) the extract, as it is or after the concentration, is suspended in water and then dissolved through neutralization thereof or (2) to the extract are added non-hydrophilic (or water-immiscible) organic solvents which are miscible with hydrophilic or water-miscible organic solvents to produce a periandrin as a precipitate which is then dissolved in water. Periandrins can be isolated from other contaminants, or periandrins themselves can also be separated from one another, by subjecting a solution containing periandrins to fractional adsorption treatment or fractional elution treatment with the carriers of ion-exchangers such as weakly basic anion-exchange resins and DEAE-crosslinked dextran, or adsorbents such as synthetic adsorbents, silica gel, granular polyamides, activated carbon, activated alumina, activated clay, and diatomaceous earth. These treatments can be generally carried out with column-chromatography methods, and their operations and conditions can be selected and established suitably in accordance with the types of the carriers used and other factors. Specific examples of purification are described below. EXAMPLE OF PURIFICATION 1 Twenty (20) kgs. of the root of Periandra dulcis was chipped into small pieces and subjected to extraction for one day with 100 liters of water at a temperature of 70° to 80° C. The extraction was repeated twice and the extract was filtered. The filtrates were combined and concentrated under reduced pressure to 8 liters. To the concentrated liquid was added an 11-fold volume of ethanol (88 liters) with stirring, and the mixture was left to cool overnight at 5° C. The separated precipitate (1.06 kg) was collected by filtration and again dissolved in 4 liters of water. To this solution was further added an 11-fold volume of ethanol (44 l.) with stirring, and the mixture was left to cool at 5° C. overnight. The same operation was repeated again and 870 g of a crude sweet-tasting fraction was obtained. The crude sweet-tasting fraction was purified by silica gel column chromatography. More particularly, 150 g of the crude sweet-tasting fraction was adsorbed onto an equivalent amount of silica gel ("Kieselgel 60" supplied by Merck & Co. Inc.), which was then charged onto a column (6 cm in diameter, 70 cm in length) that had been prepared beforehand with 1 kg of silica gel. The sweet-tasting fraction was eluted with a mixed solvent comprising n-butanol, benzene, methanol and 28% ammonia water (mixing ratio 4-3-2-2). Thus were obtained a fraction containing Periandrins I and II and a fraction containing Periandrins III and IV. The fraction containing Periandrins I and II was subjected to silica gel chromatography treatment repeatedly (2 to 3 times) with the above-mentioned mixed solvent, until the Periandrins I and II exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4). After the resulting substances were confirmed to be a single substance respectively on the thin-layer chromatography, 860 mg of Periandrin I and 240 mg of Periandrin II were obtained as crystals from hot acetic acid or a water-alcohol mixed solvent, respectively. The fraction (1.1 g) containing Periandrins III and IV was adsorbed on an equivalent amount of silica gel, which was then charged onto a column (6 cm in diameter, 70 cm in length) that had been previously prepared with 1 kg of silica gel. The column was subjected to elution with a mixed solvent consisting of chloroform, methanol and water (mixing ratio=25-17-3). The eluent was subjected to silica gel chromatography treatment repeatedly (2 to 3 times), until Periandrins III and IV exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4). After the resulting substances were confirmed to be a single substance respectively on the thin-layer chromatography, 40 mg of Periandrin III and 19 mg of Periandrin IV were obtained as crystalline powder from water, respectively. EXAMPLE OF PURIFICATION 2 Thirty (30) kgs. of the root of Periandra dulcis was chipped into small pieces and subjected to extraction for one day at room temperature with 150 liters of ca. 94% ethanol which had been adjusted to a pH of 2.0 to 2.5 with hydrochloric acid. The extraction was repeated twice and the extract was filtered. The filtrates were combined, neutralized with an alkali, and concentrated to 6 liters under reduced pressure. To the concentrated liquid was added an 11-fold volume of ethanol (66 lit.) with stirring, and the mixture was left to cool at 5° C. overnight. The separated precipitate was collected by filtration and again dissolved in 3 liters of water. To the solution was further added an 11-fold volume of ethanol (33 lit.) with stirring, and the mixture was left to cool at 5° C. overnight. The resulting precipitate (430 g) was collected by filtration. The crude sweet-tasting fraction thus obtained was purified by silica gel-column chromatography. More particularly, 100 g of the crude sweet-tasting fraction was adsorbed onto an equivalent amount of silica gel ("Kieselgel 60" supplied by Merck & Co., Inc.), which was then charged onto a column (4.5 cm in diameter, 80 cm in length) that had been prepared beforehand with 500 g of silica gel. The sweet-tasting fraction was eluted with a mixed solvent comprising n-butanol, benzene, methanol and 28% ammonia water (mixing ratio 4-3-2-2). Thus, a fraction containing Periandrins I and II and a fraction containing Periandrins III and IV were obtained. The fraction containing Periandrins I and II was repeatedly subjected to silica gel chromatography treatment (1 to 2 repetitions) with the above-mentioned mixed solvent, until the Periandrins I and II exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4). After the resulting substances were confirmed to be a single substance respectively on the thin-layer chromatography, 700 mg of Periandrin I and 170 mg of Periandrin II were obtained as crystals from hot acetic acid or a water-alcohol mixed solvent, respectively. The fraction (1.5 g) containing Periandrins III and IV was adsorbed on an equivalent amount of silica gel, which was then charged onto a column (4.5 cm in diameter, 90 cm in length) that had been previously prepared with 600 g of silica gel. The column was subjected to elution with a mixed solvent comprising chloroform, methanol and water (mixing ratio=25-17-3). The eluent was subjected to repetitions (1 to 2 times) of silica gel chromatography treatment until Periandrins III and IV exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4). After the resulting substances were confirmed to be a single substance on the thin-layer chromatography, 23 mg of Periandrin III and 9 mg of Periandrin IV were respectively obtained as crystalline powder from water. Periandrins possess a sweet taste which is refreshing and delicate. The results of tests on the degree of sweetness are shown in the following test example. TEST EXAMPLE As series of standard sweet liquids, five classes of the aqueous solutions containing 0.3 g/100 ml, 0.5 g/100 ml, 1 g/100 ml, 2 g/100 ml and 3 g/100 ml of sucrose were prepared. Separately, aqueous solutions containing 10 mg/100 ml and 20 mg/100 ml of Periandrins I through IV were respectively prepared. As controls, the aqueous solutions containing 10 mg/100 ml and 20 mg/100 ml of glycyrrhizin (supplied by Tokyo Kasei, Japan) were employed. The degrees of sweetness of these aqueous solutions containing sweet-tasting components were evaluated in comparison with the sucrose solution series by a panel of fifteen judges. The degree of sweetness as a multiple of that of sucrose was calculated as the average of values judged by the panel. The results are shown in Table 1. TABLE 1______________________________________ Degree of Sucrose equi- sweetness (mul-Solutions containing valent concen- tiple of sucrosesweet components tration sweetness)______________________________________Periandrin I 10mg/100ml 0.90 90 20mg/100ml 1.57 78.3Periandrin II 10mg/100ml 0.95 95 20mg/100ml 1.53 76.5Periandrin III 10mg/100ml 0.92 92 20mg/100ml 1.64 82Periandrin IV 10mg/100ml 0.85 85 20mg/100ml 1.60 80Glycyrrhizin 10mg/100ml 0.93 93 20mg/100ml 1.40 70______________________________________ As is apparent from Table 1, periandrins have substantially the same sweetness as glycyrrhizin. With respect to the comparison of sweetness, periandrins possess very weak or no bitter taste, whereas glycyrrhizin has a bitter taste. It was also found that the sweetness of periandrins was sensed more quickly. Thus, periandrins are quite useful as natural sweetening agents of good quality. In the above examples, the thin-layer chromatography was carried out on silica gel ("Kiesel gel 60 F254" supplied by Merck & Co., Inc., U.S.A.).
The sweet-tasting substances contained in the roots of plants of the genus Periandra were isolated and found to consist essentially of four species of novel glycosides, which were respectively named Periandrins I, II, III and IV. The Periandrins are defined by chemical formulas as well as their physical and chemical properties and are useful, for example, as natural sweetening agents.
Summarize the key points of the given document.
[ "CROSS REFERENCE TO RELATED APPLICATIONS This is a continuation-in-part of application Ser.", "No. 090,308, filed Nov. 1, 1979 now abandoned, which in turn is a continuation-in-part of application Ser.", "No. 28,800, filed Apr. 10, 1979 now abandoned.", "FIELD OF THE INVENTION This invention relates to periandrins which are novel natural sweet-tasting substances.", "The plants of the genus Periandra are the leguminous shrubs which grow wild in the northern and middle parts of Brazil.", "In these native localities, the roots of these plants are called "Alcacus de terra,"", "which means "native licorice"", "in English, and have been used from ancient times for medical use and the like for purposes such as expectoration.", "The roots of these plants possess sweetness as well as a considerable degree of bitterness.", "Thus, the extracts obtained by extracting the above-mentioned roots with water, an alcohol, etc.", "could not be used, as they are, for sweeteners or sweetener aids such as licorice extracts.", "Incidentally, it has been reported that the sweet-taste component present in the roots of the Periandra plants is glycyrrhizin (Chemical Abstracts Vol. 36, p. 3319, 1942).", "SUMMARY OF THE INVENTION The present inventors have undertaken intensive research on the sweet-tasting substances contained in the roots of Periandra plants and have succeeded in isolating the sweet substances of the following four species, which have been named Periandrins I, II, III and IV, repectively.", "The periandrins provided by the present invention are represented by the following formula (A), wherein the substituent R is given in the following description and each M which is in the sugar moiety and which is also found in the moiety R is hydrogen or a cation substantially non-toxic to humans.", "##STR1## The Periandrin I is a substance in which the substituent R in the formula (A) is represented by the following formula.", "##STR2## The Periandrin II is a substance in which the R in the formula (A) is represented by the following formula.", "##STR3## The Periandrin III is a substance in which the R in the formula (A) is represented by the following formula.", "##STR4## The Periandrin IV is a substance in which the R in the formula (A) is represented by the following formula ##STR5## BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: FIGS. 1 through 4 are spectral diagrams respectively indicating the infrared absorption spectra of Periandrins I through IV.", "The samples of Periandrins I and II are in the free-acid form, and the samples of Periandrins III and IV are in the mono-ammonium salt form.", "DETAILED DESCRIPTION OF THE INVENTION Chemical structures and physical and chemical properties of Periandrins I, II, III and IV The periandrins provided in accordance with the present invention are glycosides represented by the following formula, wherein there are four Periandrins I through IV with respect to the substituent R. ##STR6## In the formula (A), each M which is in the sugar moiety and which is also found in the moiety R as shown hereinbelow is hydrogen or a cation substantially non-toxic to humans such as a monovalent cation such as an alkali metal, e.g., Na and K, or ammonium or calcium.", "##STR7## Periandrin I in its free-acid form (M═H) has the following physical and chemical properties.", "(a) Melting point: >300° C. (turning black in the vicinity of 190° C.) (b) Specific rotation: [α] D 20 -23.0° (C=1.0, water) (c) Molecular weight: 822 (FD mass spectrometric analysis, M + .", "Na=846) (d) Elemental analysis: C 42 H 62 O 16 [.", "].4H 2 O Found: C 56.52%, H 7.61%.", "Calculated: C 56.36%, H 7.88%.", "(e) Compositional formula: C 42 H 62 O 16 (f) Infrared absorption spectrum: ν max KBr 3400, 3200, 1700, 1600, 1400, 1100, 625 cm -1 (cf.", "FIG. 1) (g) Solubilities: very soluble in water;", "soluble in pyridine;", "slightly soluble in methanol and ethanol (h) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonia water=4-3-2-3 Rf value 0.18 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.44 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.17 (i) Ultraviolet absorption spectrum: endabsorption (j) Appearance: colorless rectangular plate crystals (water-methanol mixed solvent) Periandrin II Periandrin II is a substance represented by the following formula, in which M has been defined hereinbefore.", "##STR8## Periandrin II in its free-acid form (M═H) has the following physical and chemical properties.", "(a) Melting point: 216° to 220° C. (decomposed) (b) Specific rotation: [α] D 28 +37.0° C. (C=0.27, water) (c) Elemental analysis: C 42 H 62 O 16 [.", "].3H 2 O Found: C, 57.93% H, 7.80%.", "Calculated: C, 57.52% H, 7.82%.", "(d) Compositional formula: C 42 H 62 O 16 (e) Infrared absorption spectrum: ν max KBr 3400, 3200, 2950, 1710, 1600, 1400, 1060 cm -1 (cf.", "FIG. 2) (f) Solubilities: very soluble in water;", "soluble in pyridine;", "slightly soluble in methanol and ethanol.", "(g) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonia water=4-3-2-3 Rf value 0.18 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.44 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.21 (h) Ultraviolet absorption spectrum: endabsorption (i) Appearance: colorless rectangular plate crystals (water-methanol mixed solvent) Periandrin III Periandrin III is a substance represented by the following formula, in which M has been defined hereinbefore.", "##STR9## Periandrin III in its free-acid form (M═H) has the following physical and chemical properties.", "(a) Melting point: >300° C. (b) Specific rotation: [α] D 18 -24.5° (C=1.1, water) (c) Elemental analysis: C 42 H 64 O 16 [.", "].2H 2 O Found: C 58.07%, H 8.17%.", "Calculated: C 58.59%, H 7.96%.", "(d) Compositional formula: C 42 H 64 O 16 (e) Infrared absorption spectrum: ν max KBr (the mono-ammonium salt) 3400, 2930, 1700, 1600 1408, 1040 cm -1 (cf.", "FIG. 3) (f) Solubilities: very soluble in water;", "soluble in pyridine;", "slightly soluble in methanol and ethanol (g) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonia water=4-3-2-3 Rf value 0.15 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.40 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.14 (h) Ultraviolet absorption spectrum: endabsorption (i) Appearance: colorless crystalline powder Periandrin IV Periandrin IV is a substance represented by the following formula, in which M has been defined hereinbefore.", "##STR10## Periandrin IV in its free-acid form (M═H) has the following physical and chemical properties.", "(a) Melting point: >300° C. (b) Specific rotation: [α] D 22 +96° (C=2.5, water) (c) Elemental analysis: C 42 H 64 O 16 [.", "].3H 2 O Found: C 57.01%, H 7.70%.", "Calculated: C 57.39%, H 8.03%.", "(d) Compositional formula: C 42 H 64 O 16 (e) Infrared absorption spectrum: ν max KBr (the mono-ammonium salt) 3400, 2920, 1700, 1600 1407, 1045 cm -1 (cf.", "FIG. 4) (f) Solubilities: very soluble in water;", "soluble in pyridine;", "slightly soluble in methanol and ethanol (g) Thin-layer chromatography (1) n-butanol-benzene-methanol-28% ammonium water=4-3-2-3 Rf value 0.15 (2) methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2 Rf value 0.40 (3) ethyl acetate-n-propanol-water=7-5-4 Rf value 0.19 (h) Ultraviolet absorption spectrum: endabsorption (i) Appearance: colorless crystalline powder Extraction and purification of periandrins Periandrins are present in the roots of the plants of the genus Periandra, which are typically represented by Periandra mediteranea, Periandra dulcis, etc.", "The roots of these plants or these roots in dried state are subjected to extraction of the periandrins, if desired, after they have been chipped or ground.", "The extraction is generally carried out by employing, as an extracting reagent, (i) water or a water-hydrophilic or water-miscible organic solvent containing not more than about 80% of a hydrophilic or water miscible organic solvent (such as methanol, ethanol, propanol, butanol, acetone, and methyl ethyl ketone) under the condition of a pH not lower than 3, or (ii) a water-containing or aqueous hydrophilic organic solvent (such as ethanol containing not more than 15% of water) under an acidic condition of a pH lower than 3.", "The temperature for the extraction is not especially restricted, and can be in the range of higher than the freezing point of the extracting reagent and lower than its boiling point.", "Under the condition of a low temperature, there is an advantage in that the resulting extract is accompanied by a smaller amount of impurities although a longer time is required for leaching.", "Under the condition of a high temperature, the period of time for the extraction is advantageously shortened.", "The period of time for extraction can be optionally selected in accordance with the type of extracting reagent, temperature for extraction and other conditions.", "The efficiency of extraction can be increased by incorporating alkalis, polyphosphates and/or surface active agents into the extracting reagent.", "The isolation and purification of periandrins from the resulting extract can be carried out by combining suitably conventional purification methods such as (a) an acid precipitation method, (b) a method of extraction with water-containing or aqueous acidic hydrophilic or water-miscible organic solvents of a pH lower than 3, (c) a precipitation method using hydrophilic or water-miscible organic solvents of a pH not lower than 3, (d) a method of fractionation by ion-exchange or adsorption chromatography, (e) a method of treatment with molecular sieve membrane or dialysis membrane, and (f) a recrystallization method.", "The outlines of the typical purification methods are given below.", "Periandrins are precipitated from their aqueous solution systems under acidic conditions of a pH lower than 3.", "In this case, the major parts of the bitter substance contaminating the extract remain in the solution as they are.", "When mineral acids such as hydrochloric acid and sulfuric acid are added to the aqueous solution which has been directly prepared from the extract to carry out acid-precipitation treatment, periandrins are precipitated together with proteins and various acid-insoluble substances.", "In order to reduce the coprecipitation of proteins and the like, it is also possible to resort, depending on the necessity, to pretreatment steps such as (i) a method of decomposing the acid-insoluble substances such as proteins into acid-soluble peptides or amino acids according to a treatment with enzymes such as protease, (ii) a method of heating the proteins at a temperature of 70° C. or higher to coagulate and remove them, and (iii) a method of adding to the solution metal hydroxides such as calcium hydroxide, magnesium hydroxide and aluminium hydroxide or first adding to the solution inorganic salts of these metals and then adjusting the solution to an alkaline pH to form a metal hydroxide in the solution whereby proteins are precipitated and removed.", "In the case of the acid precipitation treatment, the yield of precipitate may be increased by the salt-out effect in the presence of neutral salts such as sodium chloride, sodium sulfate, sodium nitrate, sodium formate and sodium acetate.", "Under the pH conditions in the range of weak acidity of a pH of 3 or higher to alkalinity, the solubility of periandrins with respect to a solution containing about 85% or more hydrophilic or water miscible organic solvents is low, but the bitter substances are soluble therein, whereby the periandrins and bitter-taste substances can be separated.", "Thus, a periandrin can be separated and collected as a precipitate by adding a hydrophilic or water-miscible organic solvent in an amount such as 85% or more, preferably 95% or more, to the aqueous extract, the concentrated solution or solid of the separated and purified extract solution, or the solution prepared by neutralizing and dissolving the precipitate of the above-mentioned acid precipitation step.", "A periandrin can also be obtained as a precipitate from the extract obtained according to the extracting method with water-containing hydrophilic organic solvents of a pH lower than 3, by simply adjusting the pH of the extract to 3 or higher with alkalis.", "Since a periandrin is soluble at a pH lower than 3 in water-containing (or aqueous) hydrophilic (or water-miscible) organic solvents such as an aqueous ethanol, the aqueous extract is concentrated and adjusted to an acidic pH or the precipitate formed by the above-mentioned acid precipitation treatment is collected and, if necessary, adjusted to an acidic pH, and then hydrophilic organic solvent is added thereto in such an amount as to cause the concentration to be 85% or higher, preferably 95% or higher.", "Periandrins can be thus extracted.", "As a method of preparing an aqueous solution of a periandrin from the resulting extract, insoluble residues are removed from the extract and (1) the extract, as it is or after the concentration, is suspended in water and then dissolved through neutralization thereof or (2) to the extract are added non-hydrophilic (or water-immiscible) organic solvents which are miscible with hydrophilic or water-miscible organic solvents to produce a periandrin as a precipitate which is then dissolved in water.", "Periandrins can be isolated from other contaminants, or periandrins themselves can also be separated from one another, by subjecting a solution containing periandrins to fractional adsorption treatment or fractional elution treatment with the carriers of ion-exchangers such as weakly basic anion-exchange resins and DEAE-crosslinked dextran, or adsorbents such as synthetic adsorbents, silica gel, granular polyamides, activated carbon, activated alumina, activated clay, and diatomaceous earth.", "These treatments can be generally carried out with column-chromatography methods, and their operations and conditions can be selected and established suitably in accordance with the types of the carriers used and other factors.", "Specific examples of purification are described below.", "EXAMPLE OF PURIFICATION 1 Twenty (20) kgs.", "of the root of Periandra dulcis was chipped into small pieces and subjected to extraction for one day with 100 liters of water at a temperature of 70° to 80° C. The extraction was repeated twice and the extract was filtered.", "The filtrates were combined and concentrated under reduced pressure to 8 liters.", "To the concentrated liquid was added an 11-fold volume of ethanol (88 liters) with stirring, and the mixture was left to cool overnight at 5° C. The separated precipitate (1.06 kg) was collected by filtration and again dissolved in 4 liters of water.", "To this solution was further added an 11-fold volume of ethanol (44 l.) with stirring, and the mixture was left to cool at 5° C. overnight.", "The same operation was repeated again and 870 g of a crude sweet-tasting fraction was obtained.", "The crude sweet-tasting fraction was purified by silica gel column chromatography.", "More particularly, 150 g of the crude sweet-tasting fraction was adsorbed onto an equivalent amount of silica gel ("Kieselgel 60"", "supplied by Merck &", "Co. Inc.), which was then charged onto a column (6 cm in diameter, 70 cm in length) that had been prepared beforehand with 1 kg of silica gel.", "The sweet-tasting fraction was eluted with a mixed solvent comprising n-butanol, benzene, methanol and 28% ammonia water (mixing ratio 4-3-2-2).", "Thus were obtained a fraction containing Periandrins I and II and a fraction containing Periandrins III and IV.", "The fraction containing Periandrins I and II was subjected to silica gel chromatography treatment repeatedly (2 to 3 times) with the above-mentioned mixed solvent, until the Periandrins I and II exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4).", "After the resulting substances were confirmed to be a single substance respectively on the thin-layer chromatography, 860 mg of Periandrin I and 240 mg of Periandrin II were obtained as crystals from hot acetic acid or a water-alcohol mixed solvent, respectively.", "The fraction (1.1 g) containing Periandrins III and IV was adsorbed on an equivalent amount of silica gel, which was then charged onto a column (6 cm in diameter, 70 cm in length) that had been previously prepared with 1 kg of silica gel.", "The column was subjected to elution with a mixed solvent consisting of chloroform, methanol and water (mixing ratio=25-17-3).", "The eluent was subjected to silica gel chromatography treatment repeatedly (2 to 3 times), until Periandrins III and IV exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4).", "After the resulting substances were confirmed to be a single substance respectively on the thin-layer chromatography, 40 mg of Periandrin III and 19 mg of Periandrin IV were obtained as crystalline powder from water, respectively.", "EXAMPLE OF PURIFICATION 2 Thirty (30) kgs.", "of the root of Periandra dulcis was chipped into small pieces and subjected to extraction for one day at room temperature with 150 liters of ca.", "94% ethanol which had been adjusted to a pH of 2.0 to 2.5 with hydrochloric acid.", "The extraction was repeated twice and the extract was filtered.", "The filtrates were combined, neutralized with an alkali, and concentrated to 6 liters under reduced pressure.", "To the concentrated liquid was added an 11-fold volume of ethanol (66 lit.) with stirring, and the mixture was left to cool at 5° C. overnight.", "The separated precipitate was collected by filtration and again dissolved in 3 liters of water.", "To the solution was further added an 11-fold volume of ethanol (33 lit.) with stirring, and the mixture was left to cool at 5° C. overnight.", "The resulting precipitate (430 g) was collected by filtration.", "The crude sweet-tasting fraction thus obtained was purified by silica gel-column chromatography.", "More particularly, 100 g of the crude sweet-tasting fraction was adsorbed onto an equivalent amount of silica gel ("Kieselgel 60"", "supplied by Merck &", "Co., Inc.), which was then charged onto a column (4.5 cm in diameter, 80 cm in length) that had been prepared beforehand with 500 g of silica gel.", "The sweet-tasting fraction was eluted with a mixed solvent comprising n-butanol, benzene, methanol and 28% ammonia water (mixing ratio 4-3-2-2).", "Thus, a fraction containing Periandrins I and II and a fraction containing Periandrins III and IV were obtained.", "The fraction containing Periandrins I and II was repeatedly subjected to silica gel chromatography treatment (1 to 2 repetitions) with the above-mentioned mixed solvent, until the Periandrins I and II exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4).", "After the resulting substances were confirmed to be a single substance respectively on the thin-layer chromatography, 700 mg of Periandrin I and 170 mg of Periandrin II were obtained as crystals from hot acetic acid or a water-alcohol mixed solvent, respectively.", "The fraction (1.5 g) containing Periandrins III and IV was adsorbed on an equivalent amount of silica gel, which was then charged onto a column (4.5 cm in diameter, 90 cm in length) that had been previously prepared with 600 g of silica gel.", "The column was subjected to elution with a mixed solvent comprising chloroform, methanol and water (mixing ratio=25-17-3).", "The eluent was subjected to repetitions (1 to 2 times) of silica gel chromatography treatment until Periandrins III and IV exhibited a single spot respectively on a thin-layer chromatography (developing solvent: methylene chloride-methanol-ethanol-40% acetic acid=8-4-1-2, and ethyl acetate-n-propanol-water=7-5-4).", "After the resulting substances were confirmed to be a single substance on the thin-layer chromatography, 23 mg of Periandrin III and 9 mg of Periandrin IV were respectively obtained as crystalline powder from water.", "Periandrins possess a sweet taste which is refreshing and delicate.", "The results of tests on the degree of sweetness are shown in the following test example.", "TEST EXAMPLE As series of standard sweet liquids, five classes of the aqueous solutions containing 0.3 g/100 ml, 0.5 g/100 ml, 1 g/100 ml, 2 g/100 ml and 3 g/100 ml of sucrose were prepared.", "Separately, aqueous solutions containing 10 mg/100 ml and 20 mg/100 ml of Periandrins I through IV were respectively prepared.", "As controls, the aqueous solutions containing 10 mg/100 ml and 20 mg/100 ml of glycyrrhizin (supplied by Tokyo Kasei, Japan) were employed.", "The degrees of sweetness of these aqueous solutions containing sweet-tasting components were evaluated in comparison with the sucrose solution series by a panel of fifteen judges.", "The degree of sweetness as a multiple of that of sucrose was calculated as the average of values judged by the panel.", "The results are shown in Table 1.", "TABLE 1______________________________________ Degree of Sucrose equi- sweetness (mul-Solutions containing valent concen- tiple of sucrosesweet components tration sweetness)______________________________________Periandrin I 10mg/100ml 0.90 90 20mg/100ml 1.57 78.3Periandrin II 10mg/100ml 0.95 95 20mg/100ml 1.53 76.5Periandrin III 10mg/100ml 0.92 92 20mg/100ml 1.64 82Periandrin IV 10mg/100ml 0.85 85 20mg/100ml 1.60 80Glycyrrhizin 10mg/100ml 0.93 93 20mg/100ml 1.40 70______________________________________ As is apparent from Table 1, periandrins have substantially the same sweetness as glycyrrhizin.", "With respect to the comparison of sweetness, periandrins possess very weak or no bitter taste, whereas glycyrrhizin has a bitter taste.", "It was also found that the sweetness of periandrins was sensed more quickly.", "Thus, periandrins are quite useful as natural sweetening agents of good quality.", "In the above examples, the thin-layer chromatography was carried out on silica gel ("Kiesel gel 60 F254"", "supplied by Merck &", "Co., Inc., U.S.A.)." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is based on, claims priority to, and incorporates herein by reference in its entirety, U.S. Provisional Application Ser. No. 62/314,563, filed Mar. 29, 2016, and entitled “SYSTEMS AND METHODS FOR ASSESSING PROPERTIES OF BIOLOGICAL TUBES.” STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH [0002] This invention was made with government support under HL105355 awarded by the National Institutes of Health. The government has certain rights in the invention. BACKGROUND [0003] The body and its processes rely on anatomical compartmentalization to provide homeostasis and to function properly. A particular compartment type that is ubiquitous throughout the human body and other mammals is the biological tube. For example, biological tubes are part of the vascular system, the gastrointestinal system, and many other systems. In a variety of pathological states the mechanical properties of these tubes may be affected. For example in the vascular system, atherosclerotic disease may cause a thickening or stiffening of the blood vessel as well as local fibrotic or other structural changes. In the gastrointestinal system (GI), dysmotility disorders of the gastrointestinal tract may result in the tubular structure becoming hypo- or hyper-kinetic, and malignant or benign disorders may include a pathological thickening of the structure. [0004] Pathological states of hollow organs commonly affect the organs' mechanical properties. Malignancy may stiffen a tubular structure both at the site of malignancy itself and at areas in proximity to the site through local inflammation and proliferation of tissue growth, for example. Additionally, dysmotility syndromes may affect portions of the gastrointestinal tract and thereby disturb both the functioning and mechanical properties. These pathologies are difficult to diagnose through available methods because the current known techniques do not provide specificity regarding, for example, location or distribution. [0005] More particularly as an example, the purpose of the esophagus is to provide a conduit that regulates the movement of a food bolus (i.e., a chewed mass of food ready for swallowing) into the upper gastrointestinal tract. This is accomplished by the esophagus moving the bolus toward the stomach using peristalsis, which is the coordinated action of nerve and muscle tissue propelling the bolus through the esophagus to the stomach. These processes may be disrupted leading to esophageal motility disorders. Current diagnoses of these disorders are accomplished through manometry. Manometers are organized on a single straight tube using either balloons connected to sensors or sensors directly on the tube which monitor pressure which is then inserted down the esophagus to monitor changes in esophageal pressure during peristalsis. Using this type of monitoring for dysfunctional portions of the esophagus is subpar, as dysfunction segments are mapped to a single point (length down catheter) and the pressure generated at this point is a composite measure of the three dimensional structure and may either miss, or incorrectly map pathology to a location. [0006] Therefore, it would be desirable to have a system and method allowing for the enhanced measurement of the mechanical properties of a biological tube within a subject which may provide improved diagnoses for tubular disorders. SUMMARY [0007] The present disclosure provides a system and method for enhancing the measurement of the mechanical characteristics of a biological tube within a subject. The systems and methods provided herein utilize, for example, displacement of sonometric crystals to determine displacement in three dimensions to determine where in three dimensional space longitudinally (proximal to distal) and radially a given biological tube pathology lies. As a non-limiting example, disorders of the vascular and gastrointestinal systems within the body may cause mechanical aberrations within the tubular structures of those systems. The mechanical characteristics of a tubular structure may be measured to determine whether any of these aberrations exist and the extent to which they may be affecting the tubular structure and surrounding systems. Piezoelectric sensors may be embedded in an array and placed internally or externally at a measurement site of the tubular structure of interest. A known force or stress may be applied or delivered to the site by a pressure vessel, such as a balloon. The force or stress that is applied may also be endogenous, swallowing or peristalsis, or exogenous as in the aforementioned balloon. Also, the force or stress may be known or transduced in some manner. The combined system of the applied force and pressure sensor measurements may be quantified and analyzed. The mechanical characteristics analyses that this system enables may lead to improved diagnoses of pathological states for tubular structures in the body. [0008] In one configuration, a system is provided for measuring mechanical properties of a biological tube extending along an axis. The system includes a tubular substrate dimensioned to extend along the axis of the biological tube and engage the biological tube and an array of piezoelectric elements engaging the tubular substrate. The system also includes a pressure device configured to apply a fixed or variable but transduced predetermined force or stress to the biological tube and be sensed by the array when the array is engaged with the biological tube, wherein each piezoelectric element is configured to generate a signal in response to sensing application of the predetermined force. The force could also be transduced, caused by an endogenous or exogenous force, stress, or an induced pressure or motion. The system further includes a processor configured to receive the signal from at least two piezoelectric elements of the array and calculate a mechanical property of the biological tube based on signals received from the at least two piezoelectric elements in the array. [0009] In another configuration, a method is provided for measuring a mechanical property of a biological tube. The method includes arranging a plurality of piezoelectric elements about the biological tube and applying a fixed or variable but transduced predetermined force or stress to the biological tube. The force or stress could also be transduced from an endogenously or exogenously applied force. The method also includes receiving a respective signal from each piezoelectric element in the plurality of piezoelectric elements responsive to the application of the stress and calculating the mechanical property of the biological tube based on the signals received from the plurality of piezoelectric elements. [0010] The foregoing and other advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0011] FIG. 1 is a schematic diagram illustrating some example locations of piezoelectric sensors within an array in accordance with the present disclosure. [0012] FIG. 2 is a block diagram of an example signal transmission chain including a signal generator, amplifier, matching network, and transmit piezocrystal in accordance with the present disclosure. [0013] FIG. 3 is a block diagram of an example signal receiving chain including a receiver element, matching network, amplifier, filter, and digitizer in accordance with the present disclosure. [0014] FIG. 4 is a block diagram of example signal transmission and receiving chains connected to a piezoelectric element with a T/R switch in accordance with the present disclosure. [0015] FIG. 5A is an illustration of an experimental setup for sonometric esophageal testing in accordance with the present disclosure. [0016] FIG. 5B is a block diagram of the electronics for the experimental setup of FIG. 5A . [0017] FIG. 6A is a graph showing circumferential displacement measured using an example of a composite sample in accordance with the present disclosure. [0018] FIG. 6B is a graph showing longitudinal displacement measured using an example of a composite sample in accordance with the present disclosure. [0019] FIG. 6C is a graph showing pressure measured using an example of a composite sample in accordance with the present disclosure. [0020] FIG. 6D is a graph showing stress/strain measured using an example of a composite sample in accordance with the present disclosure. [0021] FIG. 6E is a graph showing E c measured using an example of a composite sample in accordance with the present disclosure. [0022] FIG. 6F is a graph showing E L measured using an example of a composite sample in accordance with the present disclosure. [0023] FIG. 7A is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E C [0024] FIG. 7B is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E L . [0025] FIG. 7C is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E I,1 . [0026] FIG. 7D is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E I,2 . [0027] FIG. 8A provides a graph showing a moduli variation versus pressure for the composite esophageal samples using the transverse isotropic model in accordance with the present disclosure. [0028] FIG. 8B provides a graph showing a moduli variation versus pressure for the composite esophageal samples using the isotropic model in accordance with the present disclosure. [0029] FIG. 9A provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E C . [0030] FIG. 9B provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E L . [0031] FIG. 9C provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E I,1 . [0032] FIG. 9D provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E I,2 . [0033] FIG. 10A provides a graph showing the variation of the moduli with pressure using the transverse isotropic model in accordance with the present disclosure. [0034] FIG. 10B provides a graph showing the variation of the moduli with pressure using the isotropic model in accordance with the present disclosure. [0035] FIG. 11A provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E C . [0036] FIG. 11B provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E L . [0037] FIG. 11C provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E I,1 . [0038] FIG. 11D provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E I,2 . [0039] FIG. 12A a graph showing the summary of moduli variation versus pressure for the muscular layer samples using the transverse isotropic model in accordance with the present disclosure. [0040] FIG. 12B a graph showing the summary of moduli variation versus pressure for the muscular layer samples using the isotropic model in accordance with the present disclosure. [0041] FIG. 13A is a graph showing circumferential displacement measurements from one composite esophageal sample. [0042] FIG. 13B is a graph showing longitudinal displacement measurements from one composite esophageal sample. [0043] FIG. 13C is a graph showing pressure measurements from one composite esophageal sample. [0044] FIG. 13D is a graph showing circumferential stress and strain curves from one composite esophageal sample. [0045] FIG. 13E is a graph showing longitudinal stress and strain curves from one composite esophageal sample. [0046] FIG. 13F is a graph showing circumferential Kirchoff stress and Green's strain from one composite esophageal sample. [0047] FIG. 14A is a graph showing circumferential displacement measurements from five repeated measurements from one mucosa-submucosa sample. [0048] FIG. 14B is a graph showing longitudinal displacement measurements from five repeated measurements from one mucosa-submucosa sample. [0049] FIG. 14C is a graph showing pressure measurements from five repeated measurements from one mucosa-submucosa sample. [0050] FIG. 14D is a graph showing circumferential stress and strain curves from five repeated measurements from one mucosa-submucosa sample. [0051] FIG. 14E is a graph showing longitudinal stress and strain curves from five repeated measurements from one mucosa-submucosa sample. [0052] FIG. 14F is a graph showing circumferential Kirchoff stress and Green's strain from five repeated measurements from one mucosa-submucosa sample. [0053] FIG. 15A is a graph showing circumferential displacement measurements from one esophageal muscle sample. [0054] FIG. 15B is a graph showing longitudinal displacement measurements from one esophageal muscle sample. [0055] FIG. 15C is a graph showing pressure measurements from one esophageal muscle sample. [0056] FIG. 15D is a graph showing circumferential stress and strain curves from one esophageal muscle sample. [0057] FIG. 15E is a graph showing longitudinal stress and strain curves from one esophageal muscle sample. [0058] FIG. 15F is a graph showing circumferential Kirchoff stress and Green's strain from one esophageal muscle sample. [0059] FIG. 16A is a graph showing Kirchoff stress versus Green's strain for composite samples. [0060] FIG. 16B is a graph showing Kirchoff stress versus Green's strain for mucosa-submucosa samples. [0061] FIG. 16C is a graph showing Kirchoff stress versus Green's strain for mucosa-submucosa samples. [0062] FIG. 17A is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the composite, S θθ . [0063] FIG. 17B is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the composite, S zz . [0064] FIG. 17C is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the mucosa-submucosa, S θθ . [0065] FIG. 17D is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show themucosa-submucosa, S zz . [0066] FIG. 17E is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the muscle, S θθ . [0067] FIG. 17F is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the muscle, S zz . DETAILED DESCRIPTION [0068] The present disclosure provides systems and method that can apply a force or stress to deform a hollow, tubular organ, and track or measure the displacement induced by that stress to evaluate the mechanical properties of the tubular organ. The force or stress may be endogenous or exogenous. In one non-limiting example, piezoelectric sensors may be used to measure pressure or force. More particularly, to perform those manipulations and measurements on a biological tube or organ, the present disclosure may use an array of piezoelectric crystals. The array may be incorporated in or attached to a sleeve, membrane, or distensible structure that may be positioned around, on the surface of, or within the tubular organ. The piezocrystals may be attached within a mesh or on the surface of the mesh, by sutures or other fixation method, or embedded in the sleeve. [0069] External pressure may be applied within a closed compliant tube where piezocrystals are mounted on the interior or exterior of that tube. Non-limiting clinical applications may include the esophagus or any other segment of the gastrointestinal (GI) tract or vasculature. [0070] In another aspect of the disclosure, the tube with the piezocrystals may be hollow for some applications, such as applications involving the arteries or veins. In this case, for example, spherical piezocrystals may be encased in the compliant hollow tube. A pressure sensor may be incorporated to monitor the pressure in real-time applications. The applied pressure may be static or dynamic. Alternatively as another non-limiting example, a static baseline may be established, and then a dynamic pressure variation may be applied. [0071] Turning to FIG. 1 , an array of piezocrystals 103 may be arranged about a tubular substrate 105 to measure displacements in multiple directions, such as the longitudinal and circumferential directions. The tubular substrate 105 may be hollow and may include a lumen 107 configured to receive a biological tube. Multiple unique transmitters 111 , 121 may be placed at different levels along the longitudinal direction of the tubular substrate 105 . For each of the transmitters 111 , 121 , there may be multiple unique receivers 113 , 115 , 123 , 125 that, as will be described, may be used to measure the diameter and length and changes thereto of a tubular organ engaged with the tubular substrate 105 . [0072] Each transmitter 111 , 121 of FIG. 1 may be driven, as a non-limiting example, using drive circuit 200 , as illustrated in FIG. 2 . The drive circuit 200 may include, as a non-limiting example, a signal generator 205 , an amplifier 207 , a matching network 209 , and, ultimately, a transmit element 211 , which may be a transmit piezocrystal. Each transmitter 111 , 121 may be controlled by a processor 213 and excited with an unencoded signal, such as a harmonic signal, with a sinusoidal signal, or with a coded signal. The transmitted signals may be emitted at a rate known as the pulse repetition frequency (PRF). The system of FIG. 2 may also include, as a non-limiting example, a pressure device 215 configured to apply a predetermined force or transduce an applied endogenous or exogenous force to a biological tube that will then be sensed by an array when the array is engaged with the biological tube. The biological tube may be one of a section of a gastrointestinal tract, an artery, a vein, or any other relevant biological tube. [0073] More particularly, referring to FIG. 3 , a receiver circuit 300 may include a receiver element 315 configured to monitor and receive signals and a matching network 317 . The received signal may be conditioned with a preamplifier 319 and filtered with an active or passive bandpass or low-pass filter 321 . The conditioned signal may then be digitized by a digitizer 323 for further analysis. If the transmitter 111 , 121 was driven by a coded signal, the digitized signals may be processed with a matched or mismatched filter. The received and processed signals may then be provided to a processor 325 to perform desired analysis and calculate one of more mechanical properties of a biological tube coupled to the transmitter 111 , 121 . Thus, as will be described, the mechanical properties may include a variety of different properties and may be formed into a report that is generated by the processor 325 . In some configurations, the processor 213 of FIG. 2 and the processor 325 of FIG. 3 may be the same processor. [0074] In particular, the signals acquired by the above-described systems may be processed by the processor 325 using upsampling and a normalized cross-correlation to find relative time differences, Δt. The relative time difference may be found by finding the peak of the normalized cross-correlation function. The processors 213 , 325 , described above, may use these time differences to calculate the change in distance, Δd, between the transmitters 111 , 121 and the receiving piezocrystal 113 , 115 , 123 , 125 using the relationship Δd=cΔt, where c is the speed of sound in the fluid and is assumed to be a constant. To extract the motion of the biological tube from the signals, a cross-correlation algorithm may be used to determine the time delays between consecutive signals. Before the cross-correlation is performed, the samples may be up-sampled by a factor of 5 to 500 MHz (or suitable sampling frequency). The normalized cross-correlation of consecutively acquired signals may be performed and the time delay associated with the peak of the normalized cross-correlation may be used to estimate the motion. These time delays may be converted to displacement by using: [0000] Δ   d n = c   Δ   t n ; ( 1 ) d n = d 0 + ∑ i = 1 n   Δ   d n ; ( 2 ) [0075] where Δd n is the incremental displacement estimated between signal acquisitions, c is the speed of sound in the fluid, Δt n is the time delay estimated between signal acquisitions, and d 0 is the initial length. With the 500 MHz sampling frequency, for example, the displacement resolution may be 3.08 μm assuming that c=1540 m/s. For each sample the initial distance between a given transmitter 111 and receiver 113 may be measured with a calipers to obtain initial distances, d 0 , for strain calculations or measured using a calibrated time-of-flight method. Over the course of several seconds while the data may be acquired, pressure may be applied or normal peristalsis or pulse wave motion will move the piezocrystals. Alternatively, instead of an applied pressure, a pulse wave motion or normal peristalsis in the esophagus, for example, may be used to move the piezoelectric elements. The motion may be extracted using the procedure described above. [0076] The arrangement of the piezoelectric elements in the array 103 as shown in FIG. 1 may allow for redundant measurements of the diameter and longitudinal motion. These redundant measurements may be averaged in a weighted or non-weighted sense depending on the received signal amplitude. [0077] To control signal interference and control against confusion between multiple transmitters 111 , 121 , the processor 213 , 325 may coordinate the acquisitions using an offset in time, such as offsetting by T prf /2 where T prf =1/PRF and transmitters 111 and 121 may alternate transmitting signals. The PRF may be chosen in order to make measurements with sufficient time resolution to capture peristaltic motion, swallowing, or pulsatile motion. Additionally, if limited receiver channels are available, time offsets may be established for the recording of signals from different receiver piezocrystals. [0078] The distances determined by the processor 213 , 325 may then be converted into strain measurements using the following process for analyzing the radial and longitudinal strain. That is, a report may be generated by the processor that includes such information. For example, the processor 325 of FIG. 3 may use a model to compute the circumferential and longitudinal moduli and display this information via a display 327 or other feedback system, which may include physical printing systems or networked communications devices, including phones or tablets. One non-limiting example of a model includes M. Bernal, M. W. Urban, D. Rosario, W. Aquino, and J. F. Greenleaf, “Measurement of biaxial mechanical properties of soft tubes and arteries using piezoelectric elements and sonometry,” Phys. Med. Biol., vol. 56, p. 3371, 2011., which is incorporated herein by reference in its entirety. [0079] Such models may use various approaches to calculate the moduli based on assumptions of isotropy of the cylinder, transverse isotropy of the cylinder, or transverse isotropy of the cylinder. These models may include a plurality of different constitutive models, a fitted model, curve fitting modeling, of a combination thereof. The stresses and strains in the circumferential directions may be calculated using the expressions for a thin walled cylinder. The stress may be calculated from the measured or applied pressure. The ultrasound and pressure measurements may be synchronized during the acquisition so that the stress-strain curves may be calculated. [0080] In one non-limiting example, a ratio of a mean composite esophageal thickness (2.5 mm) to the radius (7.3 mm) was 0.34, and in the isolated layers was 0.13, as measured in the initial pre-stress state with a pressure of approximately 5 mmHg. Strain and stress measurements may be calculated using different models. The results of the calculations from the various models may be compared in order to evaluate whether an isotropic or anisotropic model may be more appropriate. The stress may be calculated from the pressure. The ultrasound and pressure measurements may be synchronized during the acquisition so that the stress-strain curves may be calculated. [0081] The stresses and strains may be given as: [0000] σ L = Pr 2  h ; ( 3 ) σ C = Pr h ; ( 4 ) r = r out - h  /  2 ; ( 5 ) ɛ L = L - L 0 L 0 ; ( 6 ) ɛ C = r - r 0 r 0 ; ( 7 ) [0082] where σ is the stress, r is the radius, r out is the outer radius, h is the wall thickness, subscripts L and C represent the longitudinal and circumferential directions and the subscript 0 indicates the initial dimension. [0083] In the case where it is assumed that the biological tube is transversely isotropic then: [0000] E C = 3 4  σ C ɛ C ; ( 8 ) E L = σ C 2  ɛ L + 4 3  ɛ C . ( 9 ) [0084] Alternatively, if the biological tube is assumed isotropic, then: [0000] E I , 1 = 3 2  σ c ( ɛ l + 2  ɛ c ) ; ( 10 ) E I , 2 = 3 2  σ l ( 2  ɛ l + ɛ c ) ; ( 11 ) [0085] where E I,1 and E I,2 are the two equivalent relationships of the circumferential and longitudinal characterization of the biological tube tissue isotropically. If the two are not equivalent orthogonally, the equivalency may no longer hold and the tissue may be considered anisotropic. Using the measured stresses and strains, any constitutive model may be used, such as linear or nonlinear models, for example. [0086] In addition to examining thin-walled tubes, the above-described application can also be adapted for thick-walled tubes. To do so, the stress was calculated from the pressure of the esophagus and the different layers were considered as thick-walled tubes. All of the ultrasound and pressure measurements were synchronized during the acquisition so that the stress-strain curves could be calculated as follows: [0000] σ L = P i  r i , l 2 - P o , l  r o , l 2 r o , l 2 - r i , l 2 ; ( 12 ) σ C = P i  r i , l 2 - P o  r o , l 2 r o , l 2 - r i , l 2 - r o , l 2  r i , l 2  ( P o - P i ) r l  ( r o , l 2 - r i , l 2 )  l ( 13 ) h = r o - r i ; ( 14 ) ɛ L = L - L 0 L 0 ; ( 15 ) ɛ C = r o , i - r o , n r o , n ; ( 16 ) [0087] where σ is the stress, r is the radius, r o,l is the outer radius during loading, r i,l is the inner radius during loading, r o,n is the outer radius at rest, P i is the pressure in the esophagus, P o is the pressure outside the esophagus (which can be assumed to be 0, but would need to be determined in different experimental settings), h is the wall thickness, subscripts L and C represent the longitudinal and circumferential directions. [0088] In addition, a strain energy function (SEF) can be used to characterize the mechanical response to applied stress. To use the SEF in this application, its formulation is presented where in the unloaded state the radius is derived from the diameter (D o,n ): [0000] r o,n =D o,n /2  (17). [0089] The annular area of the esophagus can be assumed to be constant and incompressible so the inner radius can be calculated from measurements of the outer radius is: [0000] A n =πr o,n 2 −πr i,n 2   (18); [0000] h l =r o,l −√{square root over ( r o,l 2 −A n /π)}  (19). [0090] Using these geometric relationships, the longitudinal stretch ratio, λ zz , is given by: [0000] r i , l = r o , l 2 - A n πλ zz ; ( 20 ) λ zz = A n π  ( r o , l 2 - r i , l 2 ) . ( 21 ) [0091] The longitudinal Green's strain is [0000] E zz = λ zz 2 - 1 2 . ( 22 ) [0092] The circumferential stretch ratio, λ θθ , and the circumferential Green's strain, E θθ , are: [0000] λ θθ = r i , l + r o , l r i , n + r o , n ; ( 23 ) E θθ = λ θθ 2 - 1 2 . ( 24 ) [0093] The circumferential Kirchoff's stress is: [0000] S θθ = Δ   Pr i , l h l  λ θθ 2 ; ( 25 ) [0094] where ΔP is the change in pressure between a loaded and unloaded state. [0095] The longitudinal Kirchoff's stress is: [0000] S zz = π   Pr i , l 2 λ zz 2  π  ( r o , l 2 - r i , l 2 ) ; ( 26 ) [0096] where P=P i . [0097] Assuming that there is no shear strain, the strain-energy function is given as: [0000] ρ 0  W = C 2  exp  ( Q ) ; ( 27 ) Q = a 11  ( E θθ 2 - E θθ * 2 ) + a 22  ( E zz 2 - E zz * 2 ) + 2  a 12  ( E θθ  E zz - E θθ *  E zz * ) ; ( 28 ) [0098] where ρ 0 is the density of the wall, W is the strain energy per unit mass, C, a 11 , a 22 , and a 12 are material constants and E* θθ and E* zz are strains associated with arbitrarily selected stresses S* θθ and S* zz , which in this work is associated with the start of the data acquisition. The stresses are given as: [0000] S θθ = ∂ ( ρ 0  W ) ∂ E θθ  C   exp  ( Q )  ( a 11  E θθ + a 12  E zz ) ; ( 29 ) S zz = ∂ ( ρ 0  W ) ∂ E zz  C   exp  ( Q )  ( a 22  E zz + a 12  E θθ ) . ( 30 ) [0099] Using the chain rule for the exponential function, the stress equations can be explicitly simplified as: [0000] ∂ ( ρ 0  W ) ∂ E θθ = C 2  exp  ( Q )  ∂ Q ∂ E θθ ; ( 31 ) ∂ ( ρ 0  W ) ∂ E zz = C 2  exp  ( Q )  ∂ Q ∂ E zz ; ( 32 ) S θθ = C 2 2  exp 2  ( Q )  ( a 11  E θθ + a 12  E zz )  ( 2  a 11  E θθ + 2  a 12  E zz ) ; ( 33 ) S zz = C 2 2  exp 2  ( Q )  ( a 22  E zz + a 12  E θθ )  ( 2  a 22  E zz + 2  a 12  E θθ ) ;   where  : ( 34 ) ∂ Q ∂ E θθ = 2  a 11  E θθ + 2  a 12  E zz ; ( 35 ) ∂ Q ∂ E zz = 2  a 22  E zz + 2  a 12  E θθ . ( 36 ) [0100] Fitting of the strain energy functions was performed in MATLAB (MathWorks, Natick, Mass.) with the lsqcurvefit function with specified lower and upper bounds for the parameters C, a 11 , a 22 , and a 12 . The root-mean-square (rms) error was computed between the data and fits for S θθ and S zz . [0101] Fitting of the measured strains and pressures could be performed through different modeling approaches with theory for thin wall and thick wall tubes, with different constitutive equations, strain energy functions, curve fitting, or other modeling approaches as appropriate for the application at hand. The processors 213 , 325 , described above, may also be configured to select at least one of a model for a thick walled tubular structure and a model for a thin walled tubular structure, as appropriate for the application at hand. [0102] The coordinates for the piezoelectric elements in FIG. 1 are given in Table 1. [0000] TABLE 1 Coordinates for crystals in FIG. 1. Piezoelectric Element Coordinates T 1 (111) (0, 0, 0) T 2 (121) (D 2 /2, D 2 /2, L) R 1,1 (113) (D 1 , 0, 0) R 2,2 (115) (D 1 /2, D 1 /2, 0) R 1,2 (123) (0, 0, L) R 2,1 (125) (D 2 /2, −D 2 /2, L) [0103] The distances between the piezoelectric elements placed at (x 1 , y 1 , z 1 ) and (x 2 , y 2 , z 2 ) may be computed using: [0000] d 1,2 =√{square root over (( x 1 −x 2 ) 2 +( y 1 −y 2 ) 2 +( z 1 −z 2 ) 2 )}  (37). [0104] Based on the example configuration provided in FIG. 1 , the distances between different transmitting and receiving piezoelectric elements may be defined and computed in Table 2 where D 1 and D 2 are the diameters at levels 1 and 2 and L is the length between the two levels. [0000] TABLE 2 Distances between transmitting and receiving crystals in FIG. 1. Identifier Transmitter Receiver Distance d a,1 T 1 (111) R 1,1 (113) D 1 d b,1 T 1 (111) R 2,2 (115) {square root over (2)}D 1 d c,1 T 1 (111) R 1,2 (123) L d d,1 T 1 (111) R 2,1 (125) {square root over (D 2 2 /2 + L 2 )} d a,2 T 2 (121) R 1,1 (113) {square root over (D 2 2 /4 + (D 1 − D 2 /2) 2 + L 2 )} d b,2 T 2 (121) R 2,2 (115) {square root over (2(D 1 /2 − D 2 /2) 2 + L 2 )} d c,2 T 2 (121) R 1,2 (123) {square root over (2)}D 2 d d,2 T 2 (121) R 2,1 (125) D 2 [0105] The example unit array 103 provided in FIG. 1 , as illustrated with six piezoelectric elements (two transmitting piezoelectric elements 111 121 and four receiving piezoelectric elements 113 , 115 , 123 , 125 ) may be repeated in a number of arrays to measure peristalsis or other motions along the length of a section of the esophagus or GI tract, for example, or any biological tube. [0106] Additionally, as illustrated in FIG. 4 , the transmitting and receiving circuits may be coupled to a switchable circuit 400 that controls operation of a piezoelectric element 413 that can then switch between transmit and receive functions. For example, a signal generator 431 is coupled to an amplifier 433 and matching network 435 to form a transmission circuit. The transmission circuit is coupled through a transmit/receive switch 437 to a receive circuit that may include a matching network 439 , amplifier 441 , filter 443 , and digitizer 445 . In operation, a processor 449 may control operation of the transmit/receive switch 437 to couple the piezoelectric element 413 to the transmit circuit 431 , 433 , 435 or the receive circuit 439 , 441 , 443 , 445 and receive feedback to provide analysis and reports. Thus, FIG. 4 illustrates how the transmit and receive signal chains from FIGS. 1 and 2 , respectively, can be coupled to a common piezoelectric element 413 to create a switchable network. [0107] The above-described systems and methods can be used in a variety of applications, including GI, vascular, and other clinical analysis processes. The following provides non-limiting examples of but a few applications of the above-described systems and methods. EXAMPLES [0108] The aim of these experiments was to investigate biomechanical properties of esophageal tissues through nondestructive testing utilizing sonometry in ex vivo esophageal tissues. The esophagus represents a useful target for tissue engineering strategies based on relative simplicity in comparison to other organs. Malignant esophageal pathologies typically require resection of the esophagus and reconstruction to restore foregut continuity. Reconstruction options are limited and morbid. Current methods for mechanical testing of esophageal tissues both in vivo and ex vivo are either destructive or ignore anisotropy. [0109] The structure of the esophagus underlies its function of propulsion of food into the stomach. It performs this function through organized peristalsis as a result of synchronization of the neuromuscular components. Importantly, this function necessitates mechanical tolerances of the esophagus that are able to withstand repetitive mechanical stress and strains of passage of oral bolus down the gastro intestinal tract; the esophagus must expand from the resting collapsed state to a dilated state to accommodate oral bolus repetitively without rupture or leak. Understanding the biomechanical relationship and varied contributions of the mucosal-submucosal component and the muscular component to composite biomechanical effects is required to elucidate dysmotility syndromes as well for future work to generate suitable constructs for tissue engineered approaches to the esophagus which require resection and replacement of esophageal pathologies such as malignancy, [0110] The impact of esophageal cancer is severe, with dismal outcomes. Esophageal cancer affects approximately a half million new people worldwide annually, and is increasing in the United States. Surgical management requires esophageal resection and subsequent reconstruction. Currently reconstruction of the native esophagus is impossible given the limited redundancy of tissue and poor vascularization. Therefore, reconstruction typically utilizes autologous tissue, either gastric, small bowel, or colon as a conduit with removal of the esophagus distal to the diseased segment. These treatment modalities have been associated with high morbidity and mortality. Given these limitations in treatment, there is a critical need for a tissue engineered substitute. An esophageal substitute would ideally recapitulate the mechanical properties of the native esophagus. Generated esophageal constructs would ideally be mechanically assessed in a non-destructive method to determine suitability and fitness for implantation. [0111] The composite structure of the esophagus represents a unique opportunity for both mechanical testing and tissue engineering as compared to other tubular structures of the body. There is an easily detached interface between the esophageal mucosa-submucosa and the muscular layers. These separate layers reflect different nonlinear material properties, but the degree of anisotropy remains unclear. [0112] In this experiment a previous theory was applied for the characterization of arteries and their nonlinear mechanical response and approximate degree of anisotropy to the composite, mucosal-submucosal and muscular layers independently to determine biaxial stress strain and approximate anisotropy within the composite and separate layers of the esophagus. [0113] The methods and systems used in this experiment allow for biomechanical determination of tissue properties, particularly longitudinal and circumferential moduli. The relative contribution of mucosal-submucosal layers and muscular layers were compared to composite esophagi. Swine thoracic esophageal tissues (n=5) were tested. For example, as will be described with respect to FIG. 5A , stress was generated using pressure loading created by a continuous pressure pump system 563 , which operated as the pressure device. Preconditioning of tissue was performed by pressure loading with the pump system 563 before data was recorded. Sonometry using piezocrystals, such as using the above-described systems and methods, was utilized to determine longitudinal and circumferential strain on composite esophagi. Similarly, five mucosa-submucosal and five muscular layers from thoracic esophagi were tested independently. [0114] The experimental results for esophageal tissues using this measurement method were consistent with reported uniaxial and biaxial mechanical testing. However, this measurement method provides a non-destructive means to assess biomechanical properties. This method may be of use to characterize mechanical properties of tissue engineered esophageal constructs. [0115] Thus, a nondestructive method for mechanical assessment was applied using piezoelectric elements and sonometry, such as described above, to determine biaxial mechanical properties in ex vivo esophagi. To characterize the isotropic and anisotropic properties of esophageal tissue, multiple esophageal muscle and mucosal-submucosal layer samples, and composite esophagi were tested. Biomechanical characterizations were performed with pressure loading and measurements of the radial and longitudinal strain made using piezocrystal sonometry. From the applied pressure and measured strain values, the circumferential and longitudinal moduli were computed under assumptions of anisotropic and isotropic structure. [0116] Fifteen esophagi were harvested from 60-70 kg domestic swine euthanized according to Institutional Animal Care Use Committee guidelines. The entire esophagus: cervical, thoracic and abdominal portions were mobilized and excised through either a median sternotomy, or right thoracotomy. The fresh tissue was stored in phosphate buffered saline (NaCl 137 mmol/L KCL 2.7 mmol/L Na 2 HPO 4 10 mmol/L KH 2 PO 4 1.8 mmol/L) until transfer to −80° C. freezer. Esophageal specimens were gently mechanically separated to generate samples (composite n=5, mucosa-submucosa n=5, and muscular n=5 layers) used for testing. Small piezoelectric elements (Sonometrics, London, Ontario, Canada) were then affixed to the outer wall of the specimen using 8-0 suture, as fully described below and shown in FIG. 5 . The specimen was then trimmed so 12 cm of mid-thoracic esophagus was isolated, which was then mounted on cannulae and fixed with plastic securement ties so that 10 cm of esophageal tissue was exposed. After cannulation, each segment was filled with degassed normal saline until free of air at a baseline pressure of ˜5 mmHg and immersed vertically in a bath of normal saline 565 and mounted on a holding frame 561 . One end of the esophagus was tied off and a weight 551 was attached to give a small pre-stress to an in vivo length. The experimental setup is shown in FIG. 5 . [0117] As seen in FIG. 5A , the esophagus 503 was submerged in degassed saline and pre-strained to an in vivo length. The sonometric and pressure transducer signal processing chain is also shown alongside the experimental setup in FIG. 5B to create a fuller overview of the systems and methods employed. [0118] A proximal esophageal cannula was attached to a calibrated pressure transducer 567 that was downstream along the saline 565 from the continuous pressure pump system 563 . Deformation of the esophagus 503 under a time-varying pressure load (KDS210, Kd Scientific, Holliston, Mass.) and measured (PX319-015G5V, Omegadyne Inc., Sunbury, Ohio) and unloading sequence generated biaxial strain with observed hysteresis, allowing the circumferential and longitudinal moduli E C and E L , respectively, to be determined. This method was applied to ex vivo native esophagi with (n=5) loading and unloading cycles for preconditioning. Infusion and withdrawal of 15 mL was performed at a volume at 60 mL/min. The speed of sound in the saline 565 was assumed to be 1480 m/s and the time of flight was calculated from distances which were measured between the elements with calipers. [0119] In this non-limiting example, a piezoelectric element 511 was designated for transmission only and two other piezoelectric elements 513 , 523 were used as receivers. One of the receiving piezoelectric elements 513 was placed at the same level as the transmitting piezoelectric element 511 but across the diameter of the esophagus 503 , and the other piezoelectric element 523 was placed along the length of the esophagus 503 on the same side as the transmitting piezoelectric element 511 about 2 cm away. [0120] As illustrated in the block diagram of FIG. 5B , a signal generator 531 (33120, Agilent, Palo Alto, Calif.) was used to create a ten-cycle burst at 2 MHz (5 μs) with a pulse repetition frequency of 20 Hz. The signal was amplified by a custom-made 40 dB power amplifier 533 . The received signals on each of the receiving piezoelectric elements 513 , 523 , 515 were amplified with custom-made amplifiers and filtered with 2 MHz bandpass filters 543 . These signals were digitized at 100 MHz by a digitizer 545 (ATS460, Alazartech, Montreal, QC, Canada). The total length of time for the measurements was 60 seconds. [0121] Referring again to FIG. 5B , in this example, the piezoelectric elements 511 , 513 , 523 were coupled directly to the esophagus 503 . However, as described above, the piezoelectric elements 511 , 513 , 523 can be mounted on a substrate that is configured to engage the esophagus 503 or other tubular biological structure. That is the piezoelectric elements 511 , 513 , 523 may be mounted on a tubular substrate that is designed to wrap around or fit as a sleeve around the esophagus 503 . However, in this example, the piezoelectric elements 511 , 513 , 523 were mounted to the esophagus so that multiple measurements cycles could be performed while monitoring the relative placement of the piezoelectric elements 511 , 513 , 523 about particular positions of the esophagus 503 . Five preconditioning cycles were performed for each sample in order to obtain consistent results, but the degree of preconditioning which occurred may vary based on the sample. [0122] FIG. 6 shows a series of correlated graphs of the measured displacements and pressures, as well as the calculated stress, strains, and moduli for the anisotropic characterization of a composite sample assuming a thin walled tube geometry. The five curves are from consecutive measurements. As can be seen from the graphs, the agreement in the data is very good between acquisitions. [0123] As seen in FIGS. 6A-6F , a typical example from five repeated measurements from one composite esophageal sample. In particular, FIG. 6A shows the circumferential displacement, FIG. 6B shows the longitudinal displacement, FIG. 6C shows the pressure, FIG. 6D show the stress and strain curves, FIG. 6E show E C , and FIG. 6F shows E L . [0124] The correlated graphs in FIGS. 7A-7D show the results for the anisotropic and isotropic calculations for the five composite samples. Each curve is the mean of five repeated acquisitions. In particular, FIGS. 7A-7D show the characterization of the composite esophageal samples. The large asymptotes in the moduli at low pressures are artifacts related to low and noisy strain values that are manifested as large moduli. FIG. 7A shows E C , FIG. 7B shows E L , FIG. 7C shows E I,1 , and FIG. 7D shows E I,2 , as labeled. [0125] Using the data in FIGS. 7A-D , the medians and interquartile ranges (IQRs) at each pressure during loading and unloading were computed to evaluate the natural variation between samples for the anisotropic and isotropic characterizations. The results for these calculations are shown in the correlated graphs of FIGS. 8A and 8B . Not all samples were tested at pressures higher than 50 mmHg, therefore data from these pressures were not included in the calculated and plotted of median and IQRs for each elastic modulus. The similarity between E C and E L as well as the isotropic characterizations indicated that the composite configuration may be adequately approximated as an isotropic tube. [0126] FIGS. 8A and 8B show the variation of the moduli with pressure. The muscle layer results showed good agreement between the anisotropic and isotropic cases, so an isotropic characterization may be most appropriate. As seen in FIGS. 8A and 8B , the graphs show the summary of moduli variation versus pressure for the composite esophageal samples. Moduli at pressures greater than 50 mmHg are not presented as there were limited samples reaching those pressure values. Specifically, the graphs show the transverse isotropic model ( FIG. 8A ) and the isotropic model ( FIG. 8B ). The open symbols are the median and the error bars represent the IQR. [0127] FIGS. 9A-9D provide a series of correlated graphs illustrating the results of the anisotropic and isotropic calculations for the five mucosal layer samples. As in FIGS. 7A-7D , each curve is the mean of five repeated acquisitions. As seen in FIGS. 9A-9D , the characterization of the mucosal layer samples can be seen. FIG. 9A shows E C , FIG. 9B shows E L , FIG. 9C shows E I,1 , and FIG. 9D shows E I,2 . [0128] FIGS. 10A and 10B show the variation of the moduli with pressure. In the mucosal layer samples it was found that E L was always greater than E C and the isotropic cases did not show good agreement. In this case, an anisotropic characterization of the mucosal layer may be more appropriate. The large asymptotes in the moduli at low pressures are artifacts related to low and noisy strain values that are manifested as large moduli. Moduli at pressures greater than 24 mmHg are not presented as there were limited samples reaching those pressure values. As seen in FIGS. 10A and 10B , the graphs show the summary of moduli variation versus pressure for the mucosal layer samples. The graphs show the transverse isotropic model ( FIG. 10A ) and the isotropic model ( FIG. 10B ). The open symbols are the median and the error bars represent the IQR. [0129] FIGS. 11A-11D show results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions. The large asymptotes in the moduli at low pressures are artifacts related to low and noisy strain values that are manifested as large moduli. The graphs show the characterization of the muscle layer samples. FIG. 11A shows E C , FIG. 11B shows E L , FIG. 11C shows E I,1 , and FIG. 11D shows E I,2 . [0130] As seen in FIGS. 12A and 12B , correlated graphs are provided that show the summary of moduli variation versus pressure for the muscular layer samples. Moduli at pressures greater than 15 mmHg are not presented as there were limited samples reaching those pressure values. The graphs show the transverse isotropic model ( FIG. 12A ), and the isotropic model ( FIG. 12B ). The open symbols are the median and the error bars represent the IQR. [0131] Using this system, the displacements, longitudinal (E L ) and circumferential moduli (E C ), and pressure loading in both composite and isolated or separated specimens were able to be reproducibly demonstrated. The mucosa-submucosa E C ranged from 175-225 kPa, and E L ranged from 250-550 kPa under pressure range of 6-27 mmHg. The muscular layer E C ranged from 100-250 kPa, and E L ranged from 120-245 kPa tested over a pressure range of 6-21 mmHg. The composite esophagi E C ranged from 15-60 kPa, and E L ranged from 16-60 kPa over a pressure load of 10-70 mmHg. The data ranges are summarize in Table 3. [0000] TABLE 3 Summary of esophageal testing results. Maximal Maximal Pressure Circumferential Longitudinal Config- Range, Strain. Median Strain. uration mmHg (IQR) Median (IQR) E C , kPa E L , kPa Composite 10-70  0.44 (0.38) −0.029 (0.02)  15-60 16-60 Mucosal 6-27 0.179 (0.075) −0.031 (0.031) 175-225 250-550 Layer Muscle 6-21 0.167 (0.201) −0.008 (0.013) 100-250 120-245 Layer [0132] It was observed that the moduli of the composite samples were much lower than for the individual layers, particularly the mucosal-submucosal layer, which has been previously demonstrated and is reproduced in testing. One could make an analogy that the two layers act as springs in series, and the effective stiffness or modulus is lower than the two individual layers. [0133] Further, from these experiments it was determined that the mucosa and submucosal layers demonstrate anisotropic properties compared to the muscular and composite esophagus which appear to behave isotropically. The only pronounced change between isotropic and anisotropic models in our findings existed in the mucosa-submucosa, which has been shown to exhibit a highly oriented collagen content. [0134] The resulting data supports the use, and reproducibility of piezoelectric elements and sonometry to assess the ex vivo biaxial mechanical properties of the esophagus as a composite structure and mucosa-submucosa and muscular isolated layers. It was observed in this experiment that the composite esophagus and the muscle layer behaved as an isotropic tube, but the mucosa-submucosal layer acted as an anisotropic tube. The application of this technique may be of utility in nondestructive biomechanical assessment of tissue engineered esophagi. [0135] For the thick walled tube assumption the thick wall stress calculations or SEF equations can be used for the mechanical property characterization. In particular, as will be described, FIGS. 13A-17F show examples of the measured displacements and pressures and the calculated stress, strains for a composite, mucosa-submucosa, and muscle sample, respectively. The curves are from consecutive measurements. The agreement is generally very good between acquisitions. [0136] Specifically, FIGS. 13A-13F provide graphs showing typical example data from five repeated measurements from one composite esophageal sample. FIG. 13A shows circumferential displacement. FIG. 13B shows longitudinal displacement. FIG. 13C shows pressure. FIG. 13D shows circumferential stress and strain curves. FIG. 13E shows longitudinal stress and strain curves. FIG. 13F shows circumferential Kirchoff stress and Green's strain. [0137] FIGS. 14A-14F provide graphs showing typical example data from five repeated measurements from one mucosa-submucosa sample. FIG. 14A shows circumferential displacement. FIG. 14B shows longitudinal displacement. FIG. 14C shows pressure. FIG. 14D shows circumferential stress and strain curves. FIG. 14E shows longitudinal stress and strain curves. FIG. 14F shows circumferential Kirchoff stress and Green's strain. [0138] FIGS. 15A-15F provide graphs showing a typical example data from five repeated measurements from one esophageal muscle sample. FIG. 15A shows circumferential displacement. FIG. 15B shows longitudinal displacement. FIG. 15C shows pressure. FIG. 15D shows circumferential stress and strain curves. FIG. 15E shows longitudinal stress and strain curves. FIG. 15F shows circumferential Kirchoff stress and Green's strain. [0139] FIGS. 16A-16C provide graphs showing the circumferential Kirchoff stress versus Green's strain from one acquisition for the five samples for each configuration. In particular, FIG. 16A is a graph that shows Kirchoff stress for composite samples. FIG. 16B shows Kirchoff stress for mucosa-submucosa samples. FIG. 16C shows Kirchoff stress for muscle samples. [0140] FIGS. 17A-17F provide graphs showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions. All solid lines are the measured data and the dashed lines are the SEF fits. FIG. 17A shows data for composite, S θθ . FIG. 17B shows data for composite, S zz . FIG. 17C shows data for mucosa-submucosa, S θθ . FIG. 17D shows data for mucosa-submucosa, S zz . FIG. 17E shows data for muscle, S θθ . FIG. 17F shows data for muscle, S zz . [0141] Tables 4-6 summarize the parameter values found using the SEF fits along with the rms values to evaluate the goodness of the fits for five different esophagi samples for the composite, mucosa-submucosa, and muscle configurations, respectively. All reported values are mean±standard deviation for the repeated acquisitions for each sample. [0000] TABLE 4 Summary of SEF fit parameters and rms values for composite esophagus samples. Sample C, kPa a 11 a 22 a 12 rms S θθ , kPa rms S zz , kPa 1 16.72 ± 1.62 3.46 ± 0.12 56.59 ± 35.08 3.71 ± 0.16 1.99 ± 0.12 2.02 ± 0.09 2 22.83 ± 3.76 2.88 ± 0.32 9.05 ± 0.96 2.99 ± 0.31 1.61 ± 0.39 1.49 ± 0.36 3 18.34 ± 3.73 1.31 ± 0.07 0.10 ± 0.00 1.67 ± 0.09 1.89 ± 0.39 2.65 ± 0.54 4 56.06 ± 3.76 0.48 ± 0.03 0.10 ± 0.00 0.66 ± 0.04 0.63 ± 0.07 0.88 ± 0.10 5 72.80 ± 18.03 0.67 ± 0.08 0.10 ± 0.00 0.85 ± 0.11 1.39 ± 0.74 1.79 ± 0.91 [0000] TABLE 5 Summary of SEF fit parameters and rms values for mucosa-submucosa esophagus samples. Sample C, kPa a 11 a 22 a 12 rms S θθ , kPa rms S zz , kPa 1 0.59 ± 0.32 0.48 ± 0.33 0.10 ± 0.00 0.41 ± 0.29 0.75 ± 0.02 0.44 ± 0.01 2 0.11 ± 0.01 3.28 ± 0.36 0.10 ± 0.00 2.73 ± 0.31 1.25 ± 0.04 0.74 ± 0.02 3 0.11 ± 0.01 5.97 ± 0.84 0.10 ± 0.00 4.73 ± 0.66 1.56 ± 0.11 0.88 ± 0.06 4 0.49 ± 0.23 3.03 ± 1.34 0.10 ± 0.00 2.28 ± 1.01 1.75 ± 0.07 0.91 ± 0.04 5 0.16 ± 0.01 2.97 ± 0.28 0.10 ± 0.00 2.42 ± 0.22 1.33 ± 0.06 0.77 ± 0.03 [0000] TABLE 6 Summary of SEF fit parameters and rms values for muscle esophagus samples. Sample C, kPa a 11 a 22 a 12 rms S θθ , kPa rms S zz , kPa 1 0.21 ± 0.07 1.55 ± 0.47 0.10 ± 0.00 1.26 ± 0.39 1.60 ± 0.08 0.94 ± 0.04 2 0.10 ± 0.02 3.18 ± 0.96 0.10 ± 0.00 2.65 ± 0.79 1.19 ± 0.03 0.71 ± 0.01 3 0.99 ± 0.58 0.47 ± 0.58 0.10 ± 0.00 0.41 ± 0.49 1.22 ± 0.03 0.70 ± 0.01 4 0.71 ± 0.41 2.13 ± 1.71 0.10 ± 0.00 1.64 ± 1.32 1.92 ± 0.08 1.02 ± 0.05 5 0.05 ± 0.02 30.03 ± 2.05 0.86 ± 1.69 24.44 ± 1.66  1.56 ± 0.06 0.91 ± 0.04 [0142] The C values were much higher in the composite samples compared to the mucosal and muscular samples. We also observed variation among the different samples for a given configuration. One aspect of the fitting that was found is that the a 22 value was set to a minimum value of 0.1 and often returned that limiting value, which indicated an insensitivity to the E zz values that it modifies. The rms values for the SEF fits were on the same order for the samples with mean values ranging from 0.44-2.66 kPa. [0143] Using strain energy functions would have significant utility in determination of behavior under stress for structures which the thin walled assumption of structure is not valid and must be instead modeled as a thick walled tube. This has implications for testing GI system organs (thick walled) compared to selected vascular structures (variably thin walled tubes). While approaches such as optical tracking may be useful for ex vivo structures, in vivo approaches to monitor strain can be difficult and not feasible to be performed in vivo using optical tracking methods. [0144] In summary, the above-described, non-destructive biaxial measurements compare favorably with other investigations of esophageal mechanics despite differences in species, testing methodology and modeling approach. The results from testing demonstrate that biaxial mechanical properties of excised esophagus may be reproducibly determined using piezoelectric elements and sonometry. Determination of biaxial mechanical properties in a non-destructive manner may allow for in vivo approaches for assessment and diagnosis of esophageal motility disorders as well as biomechanical quantification of tissue engineered constructs for esophageal replacement. [0145] A strong advantage of the methods employed in this example is the nondestructive nature of evaluating the intact esophagus or individual layers. Other mechanical testing approaches currently used are destructive and only use a small portion of the sample. The results of a non-destructive approach may be used for future modeling of the biomechanics of the esophagus under varied conditions. [0146] The present invention has been described in terms of one or more preferred embodiments, and it should be appreciated that many equivalents, alternatives, variations, and modifications, aside from those expressly stated, are possible and within the scope of the invention.
A system and method is provided for measuring a mechanical property of a biological tube. The system and method operate to arrange a plurality of piezoelectric elements about the biological tube and apply a predetermined force or transduce an endogeneous or exogeneous force to the biological tube. The system and method also operate to receive a respective signal from each piezoelectric element in the plurality of piezoelectric elements responsive to the application of the predetermined force or a transduced endogenous or exogeneous force and calculate the mechanical property of the biological tube based on the signals received from the plurality of piezoelectric elements.
Identify the most important claim in the given context and summarize it
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is based on, claims priority to, and incorporates herein by reference in its entirety, U.S. Provisional Application Ser.", "No. 62/314,563, filed Mar. 29, 2016, and entitled “SYSTEMS AND METHODS FOR ASSESSING PROPERTIES OF BIOLOGICAL TUBES.”", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH [0002] This invention was made with government support under HL105355 awarded by the National Institutes of Health.", "The government has certain rights in the invention.", "BACKGROUND [0003] The body and its processes rely on anatomical compartmentalization to provide homeostasis and to function properly.", "A particular compartment type that is ubiquitous throughout the human body and other mammals is the biological tube.", "For example, biological tubes are part of the vascular system, the gastrointestinal system, and many other systems.", "In a variety of pathological states the mechanical properties of these tubes may be affected.", "For example in the vascular system, atherosclerotic disease may cause a thickening or stiffening of the blood vessel as well as local fibrotic or other structural changes.", "In the gastrointestinal system (GI), dysmotility disorders of the gastrointestinal tract may result in the tubular structure becoming hypo- or hyper-kinetic, and malignant or benign disorders may include a pathological thickening of the structure.", "[0004] Pathological states of hollow organs commonly affect the organs'", "mechanical properties.", "Malignancy may stiffen a tubular structure both at the site of malignancy itself and at areas in proximity to the site through local inflammation and proliferation of tissue growth, for example.", "Additionally, dysmotility syndromes may affect portions of the gastrointestinal tract and thereby disturb both the functioning and mechanical properties.", "These pathologies are difficult to diagnose through available methods because the current known techniques do not provide specificity regarding, for example, location or distribution.", "[0005] More particularly as an example, the purpose of the esophagus is to provide a conduit that regulates the movement of a food bolus (i.e., a chewed mass of food ready for swallowing) into the upper gastrointestinal tract.", "This is accomplished by the esophagus moving the bolus toward the stomach using peristalsis, which is the coordinated action of nerve and muscle tissue propelling the bolus through the esophagus to the stomach.", "These processes may be disrupted leading to esophageal motility disorders.", "Current diagnoses of these disorders are accomplished through manometry.", "Manometers are organized on a single straight tube using either balloons connected to sensors or sensors directly on the tube which monitor pressure which is then inserted down the esophagus to monitor changes in esophageal pressure during peristalsis.", "Using this type of monitoring for dysfunctional portions of the esophagus is subpar, as dysfunction segments are mapped to a single point (length down catheter) and the pressure generated at this point is a composite measure of the three dimensional structure and may either miss, or incorrectly map pathology to a location.", "[0006] Therefore, it would be desirable to have a system and method allowing for the enhanced measurement of the mechanical properties of a biological tube within a subject which may provide improved diagnoses for tubular disorders.", "SUMMARY [0007] The present disclosure provides a system and method for enhancing the measurement of the mechanical characteristics of a biological tube within a subject.", "The systems and methods provided herein utilize, for example, displacement of sonometric crystals to determine displacement in three dimensions to determine where in three dimensional space longitudinally (proximal to distal) and radially a given biological tube pathology lies.", "As a non-limiting example, disorders of the vascular and gastrointestinal systems within the body may cause mechanical aberrations within the tubular structures of those systems.", "The mechanical characteristics of a tubular structure may be measured to determine whether any of these aberrations exist and the extent to which they may be affecting the tubular structure and surrounding systems.", "Piezoelectric sensors may be embedded in an array and placed internally or externally at a measurement site of the tubular structure of interest.", "A known force or stress may be applied or delivered to the site by a pressure vessel, such as a balloon.", "The force or stress that is applied may also be endogenous, swallowing or peristalsis, or exogenous as in the aforementioned balloon.", "Also, the force or stress may be known or transduced in some manner.", "The combined system of the applied force and pressure sensor measurements may be quantified and analyzed.", "The mechanical characteristics analyses that this system enables may lead to improved diagnoses of pathological states for tubular structures in the body.", "[0008] In one configuration, a system is provided for measuring mechanical properties of a biological tube extending along an axis.", "The system includes a tubular substrate dimensioned to extend along the axis of the biological tube and engage the biological tube and an array of piezoelectric elements engaging the tubular substrate.", "The system also includes a pressure device configured to apply a fixed or variable but transduced predetermined force or stress to the biological tube and be sensed by the array when the array is engaged with the biological tube, wherein each piezoelectric element is configured to generate a signal in response to sensing application of the predetermined force.", "The force could also be transduced, caused by an endogenous or exogenous force, stress, or an induced pressure or motion.", "The system further includes a processor configured to receive the signal from at least two piezoelectric elements of the array and calculate a mechanical property of the biological tube based on signals received from the at least two piezoelectric elements in the array.", "[0009] In another configuration, a method is provided for measuring a mechanical property of a biological tube.", "The method includes arranging a plurality of piezoelectric elements about the biological tube and applying a fixed or variable but transduced predetermined force or stress to the biological tube.", "The force or stress could also be transduced from an endogenously or exogenously applied force.", "The method also includes receiving a respective signal from each piezoelectric element in the plurality of piezoelectric elements responsive to the application of the stress and calculating the mechanical property of the biological tube based on the signals received from the plurality of piezoelectric elements.", "[0010] The foregoing and other advantages of the invention will appear from the following description.", "In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention.", "Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention.", "BRIEF DESCRIPTION OF THE DRAWINGS [0011] FIG. 1 is a schematic diagram illustrating some example locations of piezoelectric sensors within an array in accordance with the present disclosure.", "[0012] FIG. 2 is a block diagram of an example signal transmission chain including a signal generator, amplifier, matching network, and transmit piezocrystal in accordance with the present disclosure.", "[0013] FIG. 3 is a block diagram of an example signal receiving chain including a receiver element, matching network, amplifier, filter, and digitizer in accordance with the present disclosure.", "[0014] FIG. 4 is a block diagram of example signal transmission and receiving chains connected to a piezoelectric element with a T/R switch in accordance with the present disclosure.", "[0015] FIG. 5A is an illustration of an experimental setup for sonometric esophageal testing in accordance with the present disclosure.", "[0016] FIG. 5B is a block diagram of the electronics for the experimental setup of FIG. 5A .", "[0017] FIG. 6A is a graph showing circumferential displacement measured using an example of a composite sample in accordance with the present disclosure.", "[0018] FIG. 6B is a graph showing longitudinal displacement measured using an example of a composite sample in accordance with the present disclosure.", "[0019] FIG. 6C is a graph showing pressure measured using an example of a composite sample in accordance with the present disclosure.", "[0020] FIG. 6D is a graph showing stress/strain measured using an example of a composite sample in accordance with the present disclosure.", "[0021] FIG. 6E is a graph showing E c measured using an example of a composite sample in accordance with the present disclosure.", "[0022] FIG. 6F is a graph showing E L measured using an example of a composite sample in accordance with the present disclosure.", "[0023] FIG. 7A is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E C [0024] FIG. 7B is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E L .", "[0025] FIG. 7C is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E I,1 .", "[0026] FIG. 7D is a graph showing the results for the anisotropic and isotropic calculations for the five composite samples in accordance with the present disclosure, illustrating E I,2 .", "[0027] FIG. 8A provides a graph showing a moduli variation versus pressure for the composite esophageal samples using the transverse isotropic model in accordance with the present disclosure.", "[0028] FIG. 8B provides a graph showing a moduli variation versus pressure for the composite esophageal samples using the isotropic model in accordance with the present disclosure.", "[0029] FIG. 9A provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E C .", "[0030] FIG. 9B provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E L .", "[0031] FIG. 9C provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E I,1 .", "[0032] FIG. 9D provides a graph showing the results of the anisotropic and isotropic calculations for the five mucosal layer samples in accordance with the present disclosure, illustrating E I,2 .", "[0033] FIG. 10A provides a graph showing the variation of the moduli with pressure using the transverse isotropic model in accordance with the present disclosure.", "[0034] FIG. 10B provides a graph showing the variation of the moduli with pressure using the isotropic model in accordance with the present disclosure.", "[0035] FIG. 11A provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E C .", "[0036] FIG. 11B provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E L .", "[0037] FIG. 11C provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E I,1 .", "[0038] FIG. 11D provides a graph showing the results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions in accordance with the present disclosure, illustrating E I,2 .", "[0039] FIG. 12A a graph showing the summary of moduli variation versus pressure for the muscular layer samples using the transverse isotropic model in accordance with the present disclosure.", "[0040] FIG. 12B a graph showing the summary of moduli variation versus pressure for the muscular layer samples using the isotropic model in accordance with the present disclosure.", "[0041] FIG. 13A is a graph showing circumferential displacement measurements from one composite esophageal sample.", "[0042] FIG. 13B is a graph showing longitudinal displacement measurements from one composite esophageal sample.", "[0043] FIG. 13C is a graph showing pressure measurements from one composite esophageal sample.", "[0044] FIG. 13D is a graph showing circumferential stress and strain curves from one composite esophageal sample.", "[0045] FIG. 13E is a graph showing longitudinal stress and strain curves from one composite esophageal sample.", "[0046] FIG. 13F is a graph showing circumferential Kirchoff stress and Green's strain from one composite esophageal sample.", "[0047] FIG. 14A is a graph showing circumferential displacement measurements from five repeated measurements from one mucosa-submucosa sample.", "[0048] FIG. 14B is a graph showing longitudinal displacement measurements from five repeated measurements from one mucosa-submucosa sample.", "[0049] FIG. 14C is a graph showing pressure measurements from five repeated measurements from one mucosa-submucosa sample.", "[0050] FIG. 14D is a graph showing circumferential stress and strain curves from five repeated measurements from one mucosa-submucosa sample.", "[0051] FIG. 14E is a graph showing longitudinal stress and strain curves from five repeated measurements from one mucosa-submucosa sample.", "[0052] FIG. 14F is a graph showing circumferential Kirchoff stress and Green's strain from five repeated measurements from one mucosa-submucosa sample.", "[0053] FIG. 15A is a graph showing circumferential displacement measurements from one esophageal muscle sample.", "[0054] FIG. 15B is a graph showing longitudinal displacement measurements from one esophageal muscle sample.", "[0055] FIG. 15C is a graph showing pressure measurements from one esophageal muscle sample.", "[0056] FIG. 15D is a graph showing circumferential stress and strain curves from one esophageal muscle sample.", "[0057] FIG. 15E is a graph showing longitudinal stress and strain curves from one esophageal muscle sample.", "[0058] FIG. 15F is a graph showing circumferential Kirchoff stress and Green's strain from one esophageal muscle sample.", "[0059] FIG. 16A is a graph showing Kirchoff stress versus Green's strain for composite samples.", "[0060] FIG. 16B is a graph showing Kirchoff stress versus Green's strain for mucosa-submucosa samples.", "[0061] FIG. 16C is a graph showing Kirchoff stress versus Green's strain for mucosa-submucosa samples.", "[0062] FIG. 17A is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the composite, S θθ .", "[0063] FIG. 17B is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the composite, S zz .", "[0064] FIG. 17C is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the mucosa-submucosa, S θθ .", "[0065] FIG. 17D is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show themucosa-submucosa, S zz .", "[0066] FIG. 17E is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the muscle, S θθ .", "[0067] FIG. 17F is a graph showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions to show the muscle, S zz .", "DETAILED DESCRIPTION [0068] The present disclosure provides systems and method that can apply a force or stress to deform a hollow, tubular organ, and track or measure the displacement induced by that stress to evaluate the mechanical properties of the tubular organ.", "The force or stress may be endogenous or exogenous.", "In one non-limiting example, piezoelectric sensors may be used to measure pressure or force.", "More particularly, to perform those manipulations and measurements on a biological tube or organ, the present disclosure may use an array of piezoelectric crystals.", "The array may be incorporated in or attached to a sleeve, membrane, or distensible structure that may be positioned around, on the surface of, or within the tubular organ.", "The piezocrystals may be attached within a mesh or on the surface of the mesh, by sutures or other fixation method, or embedded in the sleeve.", "[0069] External pressure may be applied within a closed compliant tube where piezocrystals are mounted on the interior or exterior of that tube.", "Non-limiting clinical applications may include the esophagus or any other segment of the gastrointestinal (GI) tract or vasculature.", "[0070] In another aspect of the disclosure, the tube with the piezocrystals may be hollow for some applications, such as applications involving the arteries or veins.", "In this case, for example, spherical piezocrystals may be encased in the compliant hollow tube.", "A pressure sensor may be incorporated to monitor the pressure in real-time applications.", "The applied pressure may be static or dynamic.", "Alternatively as another non-limiting example, a static baseline may be established, and then a dynamic pressure variation may be applied.", "[0071] Turning to FIG. 1 , an array of piezocrystals 103 may be arranged about a tubular substrate 105 to measure displacements in multiple directions, such as the longitudinal and circumferential directions.", "The tubular substrate 105 may be hollow and may include a lumen 107 configured to receive a biological tube.", "Multiple unique transmitters 111 , 121 may be placed at different levels along the longitudinal direction of the tubular substrate 105 .", "For each of the transmitters 111 , 121 , there may be multiple unique receivers 113 , 115 , 123 , 125 that, as will be described, may be used to measure the diameter and length and changes thereto of a tubular organ engaged with the tubular substrate 105 .", "[0072] Each transmitter 111 , 121 of FIG. 1 may be driven, as a non-limiting example, using drive circuit 200 , as illustrated in FIG. 2 .", "The drive circuit 200 may include, as a non-limiting example, a signal generator 205 , an amplifier 207 , a matching network 209 , and, ultimately, a transmit element 211 , which may be a transmit piezocrystal.", "Each transmitter 111 , 121 may be controlled by a processor 213 and excited with an unencoded signal, such as a harmonic signal, with a sinusoidal signal, or with a coded signal.", "The transmitted signals may be emitted at a rate known as the pulse repetition frequency (PRF).", "The system of FIG. 2 may also include, as a non-limiting example, a pressure device 215 configured to apply a predetermined force or transduce an applied endogenous or exogenous force to a biological tube that will then be sensed by an array when the array is engaged with the biological tube.", "The biological tube may be one of a section of a gastrointestinal tract, an artery, a vein, or any other relevant biological tube.", "[0073] More particularly, referring to FIG. 3 , a receiver circuit 300 may include a receiver element 315 configured to monitor and receive signals and a matching network 317 .", "The received signal may be conditioned with a preamplifier 319 and filtered with an active or passive bandpass or low-pass filter 321 .", "The conditioned signal may then be digitized by a digitizer 323 for further analysis.", "If the transmitter 111 , 121 was driven by a coded signal, the digitized signals may be processed with a matched or mismatched filter.", "The received and processed signals may then be provided to a processor 325 to perform desired analysis and calculate one of more mechanical properties of a biological tube coupled to the transmitter 111 , 121 .", "Thus, as will be described, the mechanical properties may include a variety of different properties and may be formed into a report that is generated by the processor 325 .", "In some configurations, the processor 213 of FIG. 2 and the processor 325 of FIG. 3 may be the same processor.", "[0074] In particular, the signals acquired by the above-described systems may be processed by the processor 325 using upsampling and a normalized cross-correlation to find relative time differences, Δt.", "The relative time difference may be found by finding the peak of the normalized cross-correlation function.", "The processors 213 , 325 , described above, may use these time differences to calculate the change in distance, Δd, between the transmitters 111 , 121 and the receiving piezocrystal 113 , 115 , 123 , 125 using the relationship Δd=cΔt, where c is the speed of sound in the fluid and is assumed to be a constant.", "To extract the motion of the biological tube from the signals, a cross-correlation algorithm may be used to determine the time delays between consecutive signals.", "Before the cross-correlation is performed, the samples may be up-sampled by a factor of 5 to 500 MHz (or suitable sampling frequency).", "The normalized cross-correlation of consecutively acquired signals may be performed and the time delay associated with the peak of the normalized cross-correlation may be used to estimate the motion.", "These time delays may be converted to displacement by using: [0000] Δ   d n = c   Δ   t n ;", "( 1 ) d n = d 0 + ∑ i = 1 n   Δ   d n ;", "( 2 ) [0075] where Δd n is the incremental displacement estimated between signal acquisitions, c is the speed of sound in the fluid, Δt n is the time delay estimated between signal acquisitions, and d 0 is the initial length.", "With the 500 MHz sampling frequency, for example, the displacement resolution may be 3.08 μm assuming that c=1540 m/s.", "For each sample the initial distance between a given transmitter 111 and receiver 113 may be measured with a calipers to obtain initial distances, d 0 , for strain calculations or measured using a calibrated time-of-flight method.", "Over the course of several seconds while the data may be acquired, pressure may be applied or normal peristalsis or pulse wave motion will move the piezocrystals.", "Alternatively, instead of an applied pressure, a pulse wave motion or normal peristalsis in the esophagus, for example, may be used to move the piezoelectric elements.", "The motion may be extracted using the procedure described above.", "[0076] The arrangement of the piezoelectric elements in the array 103 as shown in FIG. 1 may allow for redundant measurements of the diameter and longitudinal motion.", "These redundant measurements may be averaged in a weighted or non-weighted sense depending on the received signal amplitude.", "[0077] To control signal interference and control against confusion between multiple transmitters 111 , 121 , the processor 213 , 325 may coordinate the acquisitions using an offset in time, such as offsetting by T prf /2 where T prf =1/PRF and transmitters 111 and 121 may alternate transmitting signals.", "The PRF may be chosen in order to make measurements with sufficient time resolution to capture peristaltic motion, swallowing, or pulsatile motion.", "Additionally, if limited receiver channels are available, time offsets may be established for the recording of signals from different receiver piezocrystals.", "[0078] The distances determined by the processor 213 , 325 may then be converted into strain measurements using the following process for analyzing the radial and longitudinal strain.", "That is, a report may be generated by the processor that includes such information.", "For example, the processor 325 of FIG. 3 may use a model to compute the circumferential and longitudinal moduli and display this information via a display 327 or other feedback system, which may include physical printing systems or networked communications devices, including phones or tablets.", "One non-limiting example of a model includes M. Bernal, M. W. Urban, D. Rosario, W. Aquino, and J. F. Greenleaf, “Measurement of biaxial mechanical properties of soft tubes and arteries using piezoelectric elements and sonometry,” Phys.", "Med.", "Biol.", ", vol.", "56, p. 3371, 2011.", ", which is incorporated herein by reference in its entirety.", "[0079] Such models may use various approaches to calculate the moduli based on assumptions of isotropy of the cylinder, transverse isotropy of the cylinder, or transverse isotropy of the cylinder.", "These models may include a plurality of different constitutive models, a fitted model, curve fitting modeling, of a combination thereof.", "The stresses and strains in the circumferential directions may be calculated using the expressions for a thin walled cylinder.", "The stress may be calculated from the measured or applied pressure.", "The ultrasound and pressure measurements may be synchronized during the acquisition so that the stress-strain curves may be calculated.", "[0080] In one non-limiting example, a ratio of a mean composite esophageal thickness (2.5 mm) to the radius (7.3 mm) was 0.34, and in the isolated layers was 0.13, as measured in the initial pre-stress state with a pressure of approximately 5 mmHg.", "Strain and stress measurements may be calculated using different models.", "The results of the calculations from the various models may be compared in order to evaluate whether an isotropic or anisotropic model may be more appropriate.", "The stress may be calculated from the pressure.", "The ultrasound and pressure measurements may be synchronized during the acquisition so that the stress-strain curves may be calculated.", "[0081] The stresses and strains may be given as: [0000] σ L = Pr 2  h ;", "( 3 ) σ C = Pr h ;", "( 4 ) r = r out - h  /  2 ;", "( 5 ) ɛ L = L - L 0 L 0 ;", "( 6 ) ɛ C = r - r 0 r 0 ;", "( 7 ) [0082] where σ is the stress, r is the radius, r out is the outer radius, h is the wall thickness, subscripts L and C represent the longitudinal and circumferential directions and the subscript 0 indicates the initial dimension.", "[0083] In the case where it is assumed that the biological tube is transversely isotropic then: [0000] E C = 3 4  σ C ɛ C ;", "( 8 ) E L = σ C 2  ɛ L + 4 3  ɛ C .", "( 9 ) [0084] Alternatively, if the biological tube is assumed isotropic, then: [0000] E I , 1 = 3 2  σ c ( ɛ l + 2  ɛ c ) ;", "( 10 ) E I , 2 = 3 2  σ l ( 2  ɛ l + ɛ c ) ;", "( 11 ) [0085] where E I,1 and E I,2 are the two equivalent relationships of the circumferential and longitudinal characterization of the biological tube tissue isotropically.", "If the two are not equivalent orthogonally, the equivalency may no longer hold and the tissue may be considered anisotropic.", "Using the measured stresses and strains, any constitutive model may be used, such as linear or nonlinear models, for example.", "[0086] In addition to examining thin-walled tubes, the above-described application can also be adapted for thick-walled tubes.", "To do so, the stress was calculated from the pressure of the esophagus and the different layers were considered as thick-walled tubes.", "All of the ultrasound and pressure measurements were synchronized during the acquisition so that the stress-strain curves could be calculated as follows: [0000] σ L = P i  r i , l 2 - P o , l  r o , l 2 r o , l 2 - r i , l 2 ;", "( 12 ) σ C = P i  r i , l 2 - P o  r o , l 2 r o , l 2 - r i , l 2 - r o , l 2  r i , l 2  ( P o - P i ) r l  ( r o , l 2 - r i , l 2 )  l ( 13 ) h = r o - r i ;", "( 14 ) ɛ L = L - L 0 L 0 ;", "( 15 ) ɛ C = r o , i - r o , n r o , n ;", "( 16 ) [0087] where σ is the stress, r is the radius, r o,l is the outer radius during loading, r i,l is the inner radius during loading, r o,n is the outer radius at rest, P i is the pressure in the esophagus, P o is the pressure outside the esophagus (which can be assumed to be 0, but would need to be determined in different experimental settings), h is the wall thickness, subscripts L and C represent the longitudinal and circumferential directions.", "[0088] In addition, a strain energy function (SEF) can be used to characterize the mechanical response to applied stress.", "To use the SEF in this application, its formulation is presented where in the unloaded state the radius is derived from the diameter (D o,n ): [0000] r o,n =D o,n /2 (17).", "[0089] The annular area of the esophagus can be assumed to be constant and incompressible so the inner radius can be calculated from measurements of the outer radius is: [0000] A n =πr o,n 2 −πr i,n 2 (18);", "[0000] h l =r o,l −√{square root over ( r o,l 2 −A n /π)} (19).", "[0090] Using these geometric relationships, the longitudinal stretch ratio, λ zz , is given by: [0000] r i , l = r o , l 2 - A n πλ zz ;", "( 20 ) λ zz = A n π  ( r o , l 2 - r i , l 2 ) .", "( 21 ) [0091] The longitudinal Green's strain is [0000] E zz = λ zz 2 - 1 2 .", "( 22 ) [0092] The circumferential stretch ratio, λ θθ , and the circumferential Green's strain, E θθ , are: [0000] λ θθ = r i , l + r o , l r i , n + r o , n ;", "( 23 ) E θθ = λ θθ 2 - 1 2 .", "( 24 ) [0093] The circumferential Kirchoff's stress is: [0000] S θθ = Δ   Pr i , l h l  λ θθ 2 ;", "( 25 ) [0094] where ΔP is the change in pressure between a loaded and unloaded state.", "[0095] The longitudinal Kirchoff's stress is: [0000] S zz = π   Pr i , l 2 λ zz 2  π  ( r o , l 2 - r i , l 2 ) ;", "( 26 ) [0096] where P=P i .", "[0097] Assuming that there is no shear strain, the strain-energy function is given as: [0000] ρ 0  W = C 2  exp  ( Q ) ;", "( 27 ) Q = a 11  ( E θθ 2 - E θθ * 2 ) + a 22  ( E zz 2 - E zz * 2 ) + 2  a 12  ( E θθ  E zz - E θθ *  E zz * ) ;", "( 28 ) [0098] where ρ 0 is the density of the wall, W is the strain energy per unit mass, C, a 11 , a 22 , and a 12 are material constants and E* θθ and E* zz are strains associated with arbitrarily selected stresses S* θθ and S* zz , which in this work is associated with the start of the data acquisition.", "The stresses are given as: [0000] S θθ = ∂ ( ρ 0  W ) ∂ E θθ  C   exp  ( Q )  ( a 11  E θθ + a 12  E zz ) ;", "( 29 ) S zz = ∂ ( ρ 0  W ) ∂ E zz  C   exp  ( Q )  ( a 22  E zz + a 12  E θθ ) .", "( 30 ) [0099] Using the chain rule for the exponential function, the stress equations can be explicitly simplified as: [0000] ∂ ( ρ 0  W ) ∂ E θθ = C 2  exp  ( Q )  ∂ Q ∂ E θθ ;", "( 31 ) ∂ ( ρ 0  W ) ∂ E zz = C 2  exp  ( Q )  ∂ Q ∂ E zz ;", "( 32 ) S θθ = C 2 2  exp 2  ( Q )  ( a 11  E θθ + a 12  E zz )  ( 2  a 11  E θθ + 2  a 12  E zz ) ;", "( 33 ) S zz = C 2 2  exp 2  ( Q )  ( a 22  E zz + a 12  E θθ )  ( 2  a 22  E zz + 2  a 12  E θθ ) ;", "  where  : ( 34 ) ∂ Q ∂ E θθ = 2  a 11  E θθ + 2  a 12  E zz ;", "( 35 ) ∂ Q ∂ E zz = 2  a 22  E zz + 2  a 12  E θθ .", "( 36 ) [0100] Fitting of the strain energy functions was performed in MATLAB (MathWorks, Natick, Mass.) with the lsqcurvefit function with specified lower and upper bounds for the parameters C, a 11 , a 22 , and a 12 .", "The root-mean-square (rms) error was computed between the data and fits for S θθ and S zz .", "[0101] Fitting of the measured strains and pressures could be performed through different modeling approaches with theory for thin wall and thick wall tubes, with different constitutive equations, strain energy functions, curve fitting, or other modeling approaches as appropriate for the application at hand.", "The processors 213 , 325 , described above, may also be configured to select at least one of a model for a thick walled tubular structure and a model for a thin walled tubular structure, as appropriate for the application at hand.", "[0102] The coordinates for the piezoelectric elements in FIG. 1 are given in Table 1.", "[0000] TABLE 1 Coordinates for crystals in FIG. 1. Piezoelectric Element Coordinates T 1 (111) (0, 0, 0) T 2 (121) (D 2 /2, D 2 /2, L) R 1,1 (113) (D 1 , 0, 0) R 2,2 (115) (D 1 /2, D 1 /2, 0) R 1,2 (123) (0, 0, L) R 2,1 (125) (D 2 /2, −D 2 /2, L) [0103] The distances between the piezoelectric elements placed at (x 1 , y 1 , z 1 ) and (x 2 , y 2 , z 2 ) may be computed using: [0000] d 1,2 =√{square root over (( x 1 −x 2 ) 2 +( y 1 −y 2 ) 2 +( z 1 −z 2 ) 2 )} (37).", "[0104] Based on the example configuration provided in FIG. 1 , the distances between different transmitting and receiving piezoelectric elements may be defined and computed in Table 2 where D 1 and D 2 are the diameters at levels 1 and 2 and L is the length between the two levels.", "[0000] TABLE 2 Distances between transmitting and receiving crystals in FIG. 1. Identifier Transmitter Receiver Distance d a,1 T 1 (111) R 1,1 (113) D 1 d b,1 T 1 (111) R 2,2 (115) {square root over (2)}D 1 d c,1 T 1 (111) R 1,2 (123) L d d,1 T 1 (111) R 2,1 (125) {square root over (D 2 2 /2 + L 2 )} d a,2 T 2 (121) R 1,1 (113) {square root over (D 2 2 /4 + (D 1 − D 2 /2) 2 + L 2 )} d b,2 T 2 (121) R 2,2 (115) {square root over (2(D 1 /2 − D 2 /2) 2 + L 2 )} d c,2 T 2 (121) R 1,2 (123) {square root over (2)}D 2 d d,2 T 2 (121) R 2,1 (125) D 2 [0105] The example unit array 103 provided in FIG. 1 , as illustrated with six piezoelectric elements (two transmitting piezoelectric elements 111 121 and four receiving piezoelectric elements 113 , 115 , 123 , 125 ) may be repeated in a number of arrays to measure peristalsis or other motions along the length of a section of the esophagus or GI tract, for example, or any biological tube.", "[0106] Additionally, as illustrated in FIG. 4 , the transmitting and receiving circuits may be coupled to a switchable circuit 400 that controls operation of a piezoelectric element 413 that can then switch between transmit and receive functions.", "For example, a signal generator 431 is coupled to an amplifier 433 and matching network 435 to form a transmission circuit.", "The transmission circuit is coupled through a transmit/receive switch 437 to a receive circuit that may include a matching network 439 , amplifier 441 , filter 443 , and digitizer 445 .", "In operation, a processor 449 may control operation of the transmit/receive switch 437 to couple the piezoelectric element 413 to the transmit circuit 431 , 433 , 435 or the receive circuit 439 , 441 , 443 , 445 and receive feedback to provide analysis and reports.", "Thus, FIG. 4 illustrates how the transmit and receive signal chains from FIGS. 1 and 2 , respectively, can be coupled to a common piezoelectric element 413 to create a switchable network.", "[0107] The above-described systems and methods can be used in a variety of applications, including GI, vascular, and other clinical analysis processes.", "The following provides non-limiting examples of but a few applications of the above-described systems and methods.", "EXAMPLES [0108] The aim of these experiments was to investigate biomechanical properties of esophageal tissues through nondestructive testing utilizing sonometry in ex vivo esophageal tissues.", "The esophagus represents a useful target for tissue engineering strategies based on relative simplicity in comparison to other organs.", "Malignant esophageal pathologies typically require resection of the esophagus and reconstruction to restore foregut continuity.", "Reconstruction options are limited and morbid.", "Current methods for mechanical testing of esophageal tissues both in vivo and ex vivo are either destructive or ignore anisotropy.", "[0109] The structure of the esophagus underlies its function of propulsion of food into the stomach.", "It performs this function through organized peristalsis as a result of synchronization of the neuromuscular components.", "Importantly, this function necessitates mechanical tolerances of the esophagus that are able to withstand repetitive mechanical stress and strains of passage of oral bolus down the gastro intestinal tract;", "the esophagus must expand from the resting collapsed state to a dilated state to accommodate oral bolus repetitively without rupture or leak.", "Understanding the biomechanical relationship and varied contributions of the mucosal-submucosal component and the muscular component to composite biomechanical effects is required to elucidate dysmotility syndromes as well for future work to generate suitable constructs for tissue engineered approaches to the esophagus which require resection and replacement of esophageal pathologies such as malignancy, [0110] The impact of esophageal cancer is severe, with dismal outcomes.", "Esophageal cancer affects approximately a half million new people worldwide annually, and is increasing in the United States.", "Surgical management requires esophageal resection and subsequent reconstruction.", "Currently reconstruction of the native esophagus is impossible given the limited redundancy of tissue and poor vascularization.", "Therefore, reconstruction typically utilizes autologous tissue, either gastric, small bowel, or colon as a conduit with removal of the esophagus distal to the diseased segment.", "These treatment modalities have been associated with high morbidity and mortality.", "Given these limitations in treatment, there is a critical need for a tissue engineered substitute.", "An esophageal substitute would ideally recapitulate the mechanical properties of the native esophagus.", "Generated esophageal constructs would ideally be mechanically assessed in a non-destructive method to determine suitability and fitness for implantation.", "[0111] The composite structure of the esophagus represents a unique opportunity for both mechanical testing and tissue engineering as compared to other tubular structures of the body.", "There is an easily detached interface between the esophageal mucosa-submucosa and the muscular layers.", "These separate layers reflect different nonlinear material properties, but the degree of anisotropy remains unclear.", "[0112] In this experiment a previous theory was applied for the characterization of arteries and their nonlinear mechanical response and approximate degree of anisotropy to the composite, mucosal-submucosal and muscular layers independently to determine biaxial stress strain and approximate anisotropy within the composite and separate layers of the esophagus.", "[0113] The methods and systems used in this experiment allow for biomechanical determination of tissue properties, particularly longitudinal and circumferential moduli.", "The relative contribution of mucosal-submucosal layers and muscular layers were compared to composite esophagi.", "Swine thoracic esophageal tissues (n=5) were tested.", "For example, as will be described with respect to FIG. 5A , stress was generated using pressure loading created by a continuous pressure pump system 563 , which operated as the pressure device.", "Preconditioning of tissue was performed by pressure loading with the pump system 563 before data was recorded.", "Sonometry using piezocrystals, such as using the above-described systems and methods, was utilized to determine longitudinal and circumferential strain on composite esophagi.", "Similarly, five mucosa-submucosal and five muscular layers from thoracic esophagi were tested independently.", "[0114] The experimental results for esophageal tissues using this measurement method were consistent with reported uniaxial and biaxial mechanical testing.", "However, this measurement method provides a non-destructive means to assess biomechanical properties.", "This method may be of use to characterize mechanical properties of tissue engineered esophageal constructs.", "[0115] Thus, a nondestructive method for mechanical assessment was applied using piezoelectric elements and sonometry, such as described above, to determine biaxial mechanical properties in ex vivo esophagi.", "To characterize the isotropic and anisotropic properties of esophageal tissue, multiple esophageal muscle and mucosal-submucosal layer samples, and composite esophagi were tested.", "Biomechanical characterizations were performed with pressure loading and measurements of the radial and longitudinal strain made using piezocrystal sonometry.", "From the applied pressure and measured strain values, the circumferential and longitudinal moduli were computed under assumptions of anisotropic and isotropic structure.", "[0116] Fifteen esophagi were harvested from 60-70 kg domestic swine euthanized according to Institutional Animal Care Use Committee guidelines.", "The entire esophagus: cervical, thoracic and abdominal portions were mobilized and excised through either a median sternotomy, or right thoracotomy.", "The fresh tissue was stored in phosphate buffered saline (NaCl 137 mmol/L KCL 2.7 mmol/L Na 2 HPO 4 10 mmol/L KH 2 PO 4 1.8 mmol/L) until transfer to −80° C. freezer.", "Esophageal specimens were gently mechanically separated to generate samples (composite n=5, mucosa-submucosa n=5, and muscular n=5 layers) used for testing.", "Small piezoelectric elements (Sonometrics, London, Ontario, Canada) were then affixed to the outer wall of the specimen using 8-0 suture, as fully described below and shown in FIG. 5 .", "The specimen was then trimmed so 12 cm of mid-thoracic esophagus was isolated, which was then mounted on cannulae and fixed with plastic securement ties so that 10 cm of esophageal tissue was exposed.", "After cannulation, each segment was filled with degassed normal saline until free of air at a baseline pressure of ˜5 mmHg and immersed vertically in a bath of normal saline 565 and mounted on a holding frame 561 .", "One end of the esophagus was tied off and a weight 551 was attached to give a small pre-stress to an in vivo length.", "The experimental setup is shown in FIG. 5 .", "[0117] As seen in FIG. 5A , the esophagus 503 was submerged in degassed saline and pre-strained to an in vivo length.", "The sonometric and pressure transducer signal processing chain is also shown alongside the experimental setup in FIG. 5B to create a fuller overview of the systems and methods employed.", "[0118] A proximal esophageal cannula was attached to a calibrated pressure transducer 567 that was downstream along the saline 565 from the continuous pressure pump system 563 .", "Deformation of the esophagus 503 under a time-varying pressure load (KDS210, Kd Scientific, Holliston, Mass.) and measured (PX319-015G5V, Omegadyne Inc., Sunbury, Ohio) and unloading sequence generated biaxial strain with observed hysteresis, allowing the circumferential and longitudinal moduli E C and E L , respectively, to be determined.", "This method was applied to ex vivo native esophagi with (n=5) loading and unloading cycles for preconditioning.", "Infusion and withdrawal of 15 mL was performed at a volume at 60 mL/min.", "The speed of sound in the saline 565 was assumed to be 1480 m/s and the time of flight was calculated from distances which were measured between the elements with calipers.", "[0119] In this non-limiting example, a piezoelectric element 511 was designated for transmission only and two other piezoelectric elements 513 , 523 were used as receivers.", "One of the receiving piezoelectric elements 513 was placed at the same level as the transmitting piezoelectric element 511 but across the diameter of the esophagus 503 , and the other piezoelectric element 523 was placed along the length of the esophagus 503 on the same side as the transmitting piezoelectric element 511 about 2 cm away.", "[0120] As illustrated in the block diagram of FIG. 5B , a signal generator 531 (33120, Agilent, Palo Alto, Calif.) was used to create a ten-cycle burst at 2 MHz (5 μs) with a pulse repetition frequency of 20 Hz.", "The signal was amplified by a custom-made 40 dB power amplifier 533 .", "The received signals on each of the receiving piezoelectric elements 513 , 523 , 515 were amplified with custom-made amplifiers and filtered with 2 MHz bandpass filters 543 .", "These signals were digitized at 100 MHz by a digitizer 545 (ATS460, Alazartech, Montreal, QC, Canada).", "The total length of time for the measurements was 60 seconds.", "[0121] Referring again to FIG. 5B , in this example, the piezoelectric elements 511 , 513 , 523 were coupled directly to the esophagus 503 .", "However, as described above, the piezoelectric elements 511 , 513 , 523 can be mounted on a substrate that is configured to engage the esophagus 503 or other tubular biological structure.", "That is the piezoelectric elements 511 , 513 , 523 may be mounted on a tubular substrate that is designed to wrap around or fit as a sleeve around the esophagus 503 .", "However, in this example, the piezoelectric elements 511 , 513 , 523 were mounted to the esophagus so that multiple measurements cycles could be performed while monitoring the relative placement of the piezoelectric elements 511 , 513 , 523 about particular positions of the esophagus 503 .", "Five preconditioning cycles were performed for each sample in order to obtain consistent results, but the degree of preconditioning which occurred may vary based on the sample.", "[0122] FIG. 6 shows a series of correlated graphs of the measured displacements and pressures, as well as the calculated stress, strains, and moduli for the anisotropic characterization of a composite sample assuming a thin walled tube geometry.", "The five curves are from consecutive measurements.", "As can be seen from the graphs, the agreement in the data is very good between acquisitions.", "[0123] As seen in FIGS. 6A-6F , a typical example from five repeated measurements from one composite esophageal sample.", "In particular, FIG. 6A shows the circumferential displacement, FIG. 6B shows the longitudinal displacement, FIG. 6C shows the pressure, FIG. 6D show the stress and strain curves, FIG. 6E show E C , and FIG. 6F shows E L .", "[0124] The correlated graphs in FIGS. 7A-7D show the results for the anisotropic and isotropic calculations for the five composite samples.", "Each curve is the mean of five repeated acquisitions.", "In particular, FIGS. 7A-7D show the characterization of the composite esophageal samples.", "The large asymptotes in the moduli at low pressures are artifacts related to low and noisy strain values that are manifested as large moduli.", "FIG. 7A shows E C , FIG. 7B shows E L , FIG. 7C shows E I,1 , and FIG. 7D shows E I,2 , as labeled.", "[0125] Using the data in FIGS. 7A-D , the medians and interquartile ranges (IQRs) at each pressure during loading and unloading were computed to evaluate the natural variation between samples for the anisotropic and isotropic characterizations.", "The results for these calculations are shown in the correlated graphs of FIGS. 8A and 8B .", "Not all samples were tested at pressures higher than 50 mmHg, therefore data from these pressures were not included in the calculated and plotted of median and IQRs for each elastic modulus.", "The similarity between E C and E L as well as the isotropic characterizations indicated that the composite configuration may be adequately approximated as an isotropic tube.", "[0126] FIGS. 8A and 8B show the variation of the moduli with pressure.", "The muscle layer results showed good agreement between the anisotropic and isotropic cases, so an isotropic characterization may be most appropriate.", "As seen in FIGS. 8A and 8B , the graphs show the summary of moduli variation versus pressure for the composite esophageal samples.", "Moduli at pressures greater than 50 mmHg are not presented as there were limited samples reaching those pressure values.", "Specifically, the graphs show the transverse isotropic model ( FIG. 8A ) and the isotropic model ( FIG. 8B ).", "The open symbols are the median and the error bars represent the IQR.", "[0127] FIGS. 9A-9D provide a series of correlated graphs illustrating the results of the anisotropic and isotropic calculations for the five mucosal layer samples.", "As in FIGS. 7A-7D , each curve is the mean of five repeated acquisitions.", "As seen in FIGS. 9A-9D , the characterization of the mucosal layer samples can be seen.", "FIG. 9A shows E C , FIG. 9B shows E L , FIG. 9C shows E I,1 , and FIG. 9D shows E I,2 .", "[0128] FIGS. 10A and 10B show the variation of the moduli with pressure.", "In the mucosal layer samples it was found that E L was always greater than E C and the isotropic cases did not show good agreement.", "In this case, an anisotropic characterization of the mucosal layer may be more appropriate.", "The large asymptotes in the moduli at low pressures are artifacts related to low and noisy strain values that are manifested as large moduli.", "Moduli at pressures greater than 24 mmHg are not presented as there were limited samples reaching those pressure values.", "As seen in FIGS. 10A and 10B , the graphs show the summary of moduli variation versus pressure for the mucosal layer samples.", "The graphs show the transverse isotropic model ( FIG. 10A ) and the isotropic model ( FIG. 10B ).", "The open symbols are the median and the error bars represent the IQR.", "[0129] FIGS. 11A-11D show results of the anisotropic and isotropic calculations for the five muscle layer samples and five repeated acquisitions.", "The large asymptotes in the moduli at low pressures are artifacts related to low and noisy strain values that are manifested as large moduli.", "The graphs show the characterization of the muscle layer samples.", "FIG. 11A shows E C , FIG. 11B shows E L , FIG. 11C shows E I,1 , and FIG. 11D shows E I,2 .", "[0130] As seen in FIGS. 12A and 12B , correlated graphs are provided that show the summary of moduli variation versus pressure for the muscular layer samples.", "Moduli at pressures greater than 15 mmHg are not presented as there were limited samples reaching those pressure values.", "The graphs show the transverse isotropic model ( FIG. 12A ), and the isotropic model ( FIG. 12B ).", "The open symbols are the median and the error bars represent the IQR.", "[0131] Using this system, the displacements, longitudinal (E L ) and circumferential moduli (E C ), and pressure loading in both composite and isolated or separated specimens were able to be reproducibly demonstrated.", "The mucosa-submucosa E C ranged from 175-225 kPa, and E L ranged from 250-550 kPa under pressure range of 6-27 mmHg.", "The muscular layer E C ranged from 100-250 kPa, and E L ranged from 120-245 kPa tested over a pressure range of 6-21 mmHg.", "The composite esophagi E C ranged from 15-60 kPa, and E L ranged from 16-60 kPa over a pressure load of 10-70 mmHg.", "The data ranges are summarize in Table 3.", "[0000] TABLE 3 Summary of esophageal testing results.", "Maximal Maximal Pressure Circumferential Longitudinal Config- Range, Strain.", "Median Strain.", "uration mmHg (IQR) Median (IQR) E C , kPa E L , kPa Composite 10-70 0.44 (0.38) −0.029 (0.02) 15-60 16-60 Mucosal 6-27 0.179 (0.075) −0.031 (0.031) 175-225 250-550 Layer Muscle 6-21 0.167 (0.201) −0.008 (0.013) 100-250 120-245 Layer [0132] It was observed that the moduli of the composite samples were much lower than for the individual layers, particularly the mucosal-submucosal layer, which has been previously demonstrated and is reproduced in testing.", "One could make an analogy that the two layers act as springs in series, and the effective stiffness or modulus is lower than the two individual layers.", "[0133] Further, from these experiments it was determined that the mucosa and submucosal layers demonstrate anisotropic properties compared to the muscular and composite esophagus which appear to behave isotropically.", "The only pronounced change between isotropic and anisotropic models in our findings existed in the mucosa-submucosa, which has been shown to exhibit a highly oriented collagen content.", "[0134] The resulting data supports the use, and reproducibility of piezoelectric elements and sonometry to assess the ex vivo biaxial mechanical properties of the esophagus as a composite structure and mucosa-submucosa and muscular isolated layers.", "It was observed in this experiment that the composite esophagus and the muscle layer behaved as an isotropic tube, but the mucosa-submucosal layer acted as an anisotropic tube.", "The application of this technique may be of utility in nondestructive biomechanical assessment of tissue engineered esophagi.", "[0135] For the thick walled tube assumption the thick wall stress calculations or SEF equations can be used for the mechanical property characterization.", "In particular, as will be described, FIGS. 13A-17F show examples of the measured displacements and pressures and the calculated stress, strains for a composite, mucosa-submucosa, and muscle sample, respectively.", "The curves are from consecutive measurements.", "The agreement is generally very good between acquisitions.", "[0136] Specifically, FIGS. 13A-13F provide graphs showing typical example data from five repeated measurements from one composite esophageal sample.", "FIG. 13A shows circumferential displacement.", "FIG. 13B shows longitudinal displacement.", "FIG. 13C shows pressure.", "FIG. 13D shows circumferential stress and strain curves.", "FIG. 13E shows longitudinal stress and strain curves.", "FIG. 13F shows circumferential Kirchoff stress and Green's strain.", "[0137] FIGS. 14A-14F provide graphs showing typical example data from five repeated measurements from one mucosa-submucosa sample.", "FIG. 14A shows circumferential displacement.", "FIG. 14B shows longitudinal displacement.", "FIG. 14C shows pressure.", "FIG. 14D shows circumferential stress and strain curves.", "FIG. 14E shows longitudinal stress and strain curves.", "FIG. 14F shows circumferential Kirchoff stress and Green's strain.", "[0138] FIGS. 15A-15F provide graphs showing a typical example data from five repeated measurements from one esophageal muscle sample.", "FIG. 15A shows circumferential displacement.", "FIG. 15B shows longitudinal displacement.", "FIG. 15C shows pressure.", "FIG. 15D shows circumferential stress and strain curves.", "FIG. 15E shows longitudinal stress and strain curves.", "FIG. 15F shows circumferential Kirchoff stress and Green's strain.", "[0139] FIGS. 16A-16C provide graphs showing the circumferential Kirchoff stress versus Green's strain from one acquisition for the five samples for each configuration.", "In particular, FIG. 16A is a graph that shows Kirchoff stress for composite samples.", "FIG. 16B shows Kirchoff stress for mucosa-submucosa samples.", "FIG. 16C shows Kirchoff stress for muscle samples.", "[0140] FIGS. 17A-17F provide graphs showing examples of the SEF fits and the Kirchoff stresses through time for the results shown in FIGS. 13A-16C for two consecutive acquisitions.", "All solid lines are the measured data and the dashed lines are the SEF fits.", "FIG. 17A shows data for composite, S θθ .", "FIG. 17B shows data for composite, S zz .", "FIG. 17C shows data for mucosa-submucosa, S θθ .", "FIG. 17D shows data for mucosa-submucosa, S zz .", "FIG. 17E shows data for muscle, S θθ .", "FIG. 17F shows data for muscle, S zz .", "[0141] Tables 4-6 summarize the parameter values found using the SEF fits along with the rms values to evaluate the goodness of the fits for five different esophagi samples for the composite, mucosa-submucosa, and muscle configurations, respectively.", "All reported values are mean±standard deviation for the repeated acquisitions for each sample.", "[0000] TABLE 4 Summary of SEF fit parameters and rms values for composite esophagus samples.", "Sample C, kPa a 11 a 22 a 12 rms S θθ , kPa rms S zz , kPa 1 16.72 ± 1.62 3.46 ± 0.12 56.59 ± 35.08 3.71 ± 0.16 1.99 ± 0.12 2.02 ± 0.09 2 22.83 ± 3.76 2.88 ± 0.32 9.05 ± 0.96 2.99 ± 0.31 1.61 ± 0.39 1.49 ± 0.36 3 18.34 ± 3.73 1.31 ± 0.07 0.10 ± 0.00 1.67 ± 0.09 1.89 ± 0.39 2.65 ± 0.54 4 56.06 ± 3.76 0.48 ± 0.03 0.10 ± 0.00 0.66 ± 0.04 0.63 ± 0.07 0.88 ± 0.10 5 72.80 ± 18.03 0.67 ± 0.08 0.10 ± 0.00 0.85 ± 0.11 1.39 ± 0.74 1.79 ± 0.91 [0000] TABLE 5 Summary of SEF fit parameters and rms values for mucosa-submucosa esophagus samples.", "Sample C, kPa a 11 a 22 a 12 rms S θθ , kPa rms S zz , kPa 1 0.59 ± 0.32 0.48 ± 0.33 0.10 ± 0.00 0.41 ± 0.29 0.75 ± 0.02 0.44 ± 0.01 2 0.11 ± 0.01 3.28 ± 0.36 0.10 ± 0.00 2.73 ± 0.31 1.25 ± 0.04 0.74 ± 0.02 3 0.11 ± 0.01 5.97 ± 0.84 0.10 ± 0.00 4.73 ± 0.66 1.56 ± 0.11 0.88 ± 0.06 4 0.49 ± 0.23 3.03 ± 1.34 0.10 ± 0.00 2.28 ± 1.01 1.75 ± 0.07 0.91 ± 0.04 5 0.16 ± 0.01 2.97 ± 0.28 0.10 ± 0.00 2.42 ± 0.22 1.33 ± 0.06 0.77 ± 0.03 [0000] TABLE 6 Summary of SEF fit parameters and rms values for muscle esophagus samples.", "Sample C, kPa a 11 a 22 a 12 rms S θθ , kPa rms S zz , kPa 1 0.21 ± 0.07 1.55 ± 0.47 0.10 ± 0.00 1.26 ± 0.39 1.60 ± 0.08 0.94 ± 0.04 2 0.10 ± 0.02 3.18 ± 0.96 0.10 ± 0.00 2.65 ± 0.79 1.19 ± 0.03 0.71 ± 0.01 3 0.99 ± 0.58 0.47 ± 0.58 0.10 ± 0.00 0.41 ± 0.49 1.22 ± 0.03 0.70 ± 0.01 4 0.71 ± 0.41 2.13 ± 1.71 0.10 ± 0.00 1.64 ± 1.32 1.92 ± 0.08 1.02 ± 0.05 5 0.05 ± 0.02 30.03 ± 2.05 0.86 ± 1.69 24.44 ± 1.66 1.56 ± 0.06 0.91 ± 0.04 [0142] The C values were much higher in the composite samples compared to the mucosal and muscular samples.", "We also observed variation among the different samples for a given configuration.", "One aspect of the fitting that was found is that the a 22 value was set to a minimum value of 0.1 and often returned that limiting value, which indicated an insensitivity to the E zz values that it modifies.", "The rms values for the SEF fits were on the same order for the samples with mean values ranging from 0.44-2.66 kPa.", "[0143] Using strain energy functions would have significant utility in determination of behavior under stress for structures which the thin walled assumption of structure is not valid and must be instead modeled as a thick walled tube.", "This has implications for testing GI system organs (thick walled) compared to selected vascular structures (variably thin walled tubes).", "While approaches such as optical tracking may be useful for ex vivo structures, in vivo approaches to monitor strain can be difficult and not feasible to be performed in vivo using optical tracking methods.", "[0144] In summary, the above-described, non-destructive biaxial measurements compare favorably with other investigations of esophageal mechanics despite differences in species, testing methodology and modeling approach.", "The results from testing demonstrate that biaxial mechanical properties of excised esophagus may be reproducibly determined using piezoelectric elements and sonometry.", "Determination of biaxial mechanical properties in a non-destructive manner may allow for in vivo approaches for assessment and diagnosis of esophageal motility disorders as well as biomechanical quantification of tissue engineered constructs for esophageal replacement.", "[0145] A strong advantage of the methods employed in this example is the nondestructive nature of evaluating the intact esophagus or individual layers.", "Other mechanical testing approaches currently used are destructive and only use a small portion of the sample.", "The results of a non-destructive approach may be used for future modeling of the biomechanics of the esophagus under varied conditions.", "[0146] The present invention has been described in terms of one or more preferred embodiments, and it should be appreciated that many equivalents, alternatives, variations, and modifications, aside from those expressly stated, are possible and within the scope of the invention." ]
BACKGROUND/SUMMARY [0001] Vacuum may be used to operate or to assist in the operation of various devices of a vehicle. For example, vacuum may be used to assist a driver applying vehicle brakes. In some vehicle systems vacuum is provided via a vacuum pump. Some vacuum pumps are electrically driven by motors while others are mechanically driven by the vehicle's engine. Engine driven vacuum pumps can operate at higher efficiencies than electrically driven vacuum pumps; however, operation of mechanically driven vacuum pumps is constrained by engine operation. For example, mechanically driven vacuum pumps do not pump air while the engine is not rotating. On the other hand, electrically driven vacuum pumps may be activated and deactivated without regard to engine operation so that engine fuel economy can be increased; however, electrically driven vacuum pumps can be less efficient than mechanically driven vacuum pumps. Thus, opportunities exist to improve on the operation of both electrically and mechanically driven vacuum pumps. [0002] The inventor herein has recognized the above-mentioned disadvantages and has developed an engine vacuum system, comprising: an engine; an electrically driven vacuum pump in fluid communication with the engine and a vacuum reservoir, a vacuum pump exhaust port of the electrically driven vacuum pump in fluid communication with an interior region of a crankcase or cylinder head valve cover of the engine. [0003] By directing the outlet of an electrically driven vacuum pump to an area interior to an engine, it is possible to use engine oil lubricate the mechanism and to wet the pumping chamber seals of an electrically driven pump so that the pump has higher pumping efficiency without increasing vehicle emissions. For example, air can be pumped on demand from a vacuum reservoir by an electrically driven vacuum pump to an engine crankcase. Oil used to wet seals of the vacuum pump can be deposited into the engine crankcase, and air from the vacuum reservoir can be routed to engine cylinders via a positive crankcase ventilation (PCV) system for participation in combustion of an air-fuel mixture. In this way, the pumping efficiency of the electrically driven vacuum pump can be increased without increasing engine emissions. In other examples, air exhausted from an engine driven vacuum pump with an oil wetted pumping chamber can be routed to a region of the engine enclosed by a cylinder head valve cover to reduce vehicle emissions. The valve covers enclose the valve train and limit the flow of oil and other substances to atmosphere. [0004] The present description may provide several advantages. In particular, the approach can improve the operation of electrically and engine (mechanically) driven vacuum pumps that have oil wetted seals. Further, the approach can reduce vehicle emissions for vehicles that have vacuum pumps. Further still, the approach may provide improved vacuum pump control during some conditions. [0005] The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings. [0006] It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE FIGURES [0007] FIG. 1 shows a schematic depiction of an engine; [0008] FIG. 2 shows simulated signals of interest during engine operation; [0009] FIG. 3 shows a high level flowchart of a method for operating of a vacuum pump; and [0010] FIG. 4 shows a flowchart of a method for operating a vacuum pump during selected engine operating conditions. DETAILED DESCRIPTION [0011] The present description is related to producing vacuum for use as a medium to assist in actuator operation. FIG. 1 shows one example system for producing vacuum used to assist actuator operation. FIG. 2 shows simulated signals of interest when controlling vacuum within a reservoir that supplies power to assist in actuator operation according to the methods of FIGS. 3 and 4 . [0012] Referring to FIG. 1 , internal combustion engine 10 , comprising a plurality of cylinders, one cylinder of which is shown in FIG. 1 , is controlled by electronic engine controller 12 . Engine 10 includes combustion chamber 30 and cylinder walls 32 with piston 36 positioned therein and connected to crankshaft 40 . Combustion chamber 30 is shown communicating with intake manifold 44 and exhaust manifold 48 via respective intake valve 52 and exhaust valve 54 . Each intake and exhaust valve may be operated by an intake cam 51 and an exhaust cam 53 . Alternatively, one or more of the intake and exhaust valves may be operated by an electromechanically controlled valve coil and armature assembly. The position of intake cam 51 may be determined by intake cam sensor 55 . The position of exhaust cam 53 may be determined by exhaust cam sensor 57 . Intake valve 52 and exhaust valve 54 are enclosed within cylinder head valve cover 38 which may be sealed from atmosphere. Crankshaft 40 is located within crankcase 34 as is engine oil pump 146 . Engine oil pump supplies engine oil for lubricating intake valve 52 , exhaust valve 54 , intake cam 51 , exhaust cam 53 , and vacuum pump 141 . Valve 144 is electrically activated and deactivated by controller 12 and selectively allows oil to flow from engine 10 to vacuum pump 141 . In other examples, engine oil may be supplied to vacuum pump 141 via gravity feed. For example, oil pump 146 can supply oil to intake cam 51 and exhaust cam 53 . Oil may be returned from intake cam 51 and exhaust cam 53 to crankcase 34 through vacuum pump 141 via a conduit (not shown). In still other examples, vacuum pumps are capable of drawing their own lubricating and sealing oil from the engine oil sump. [0013] Fuel injector 66 is shown positioned to inject fuel directly into cylinder 30 , which is known to those skilled in the art as direct injection. Alternatively, fuel may be injected to an intake port, which is known to those skilled in the art as port injection. Fuel injector 66 delivers liquid fuel in proportion to the pulse width of signal FPW from controller 12 . Fuel is delivered to fuel injector 66 by a fuel system (not shown) including a fuel tank, fuel pump, and fuel rail (not shown). Fuel injector 66 is supplied operating current from driver 68 which responds to controller 12 . In addition, intake manifold 44 is shown communicating with optional electronic throttle 62 which adjusts a position of throttle plate 64 to control air flow from intake boost chamber 46 to intake manifold 44 . [0014] Compressor 162 draws air from air intake 42 to supply boost chamber 46 . Exhaust gases spin turbine 164 which is coupled to compressor 162 via shaft 160 . Vacuum operated waste gate actuator 72 allows exhaust gases to bypass turbine 164 so that boost pressure can be controlled under varying operating conditions. Vacuum is supplied to waste gate actuator 72 via vacuum reservoir 139 by way of a conduit (not shown). Vacuum may also be supplied to a vacuum actuated compressor bypass valve. Vacuum pump 141 provides vacuum to brake booster 140 via conduit 147 . Check valve 149 limits air flow from vacuum pump 141 to brake booster 140 and allows air flow from brake booster 140 to vacuum pump 141 . Additional vacuum capacity is provided by vacuum reservoir 139 . Brake booster 140 includes an internal vacuum reservoir and it amplifies force provided by foot 152 via brake pedal 150 to master cylinder 148 for applying vehicle brakes (not shown). [0015] Distributorless ignition system 88 provides an ignition spark to combustion chamber 30 via spark plug 92 in response to controller 12 . Universal Exhaust Gas Oxygen (UEGO) sensor 126 is shown coupled to exhaust manifold 48 upstream of catalytic converter 70 . Alternatively, a two-state exhaust gas oxygen sensor may be substituted for UEGO sensor 126 . [0016] Converter 70 can include multiple catalyst bricks, in one example. In another example, multiple emission control devices, each with multiple bricks, can be used. Converter 70 can be a three-way type catalyst in one example. [0017] Controller 12 is shown in FIG. 1 as a conventional microcomputer including: microprocessor unit 102 , input/output ports 104 , read-only memory 106 , random access memory 108 , keep alive memory 110 , and a conventional data bus. Controller 12 is shown receiving various signals from sensors coupled to engine 10 , in addition to those signals previously discussed, including: engine coolant temperature (ECT) from temperature sensor 112 coupled to cooling sleeve 114 ; a position sensor 134 coupled to an accelerator pedal 130 for sensing accelerator position adjusted by foot 132 ; a position sensor 154 coupled to brake pedal 150 for sensing brake pedal position, a pressure sensor 142 for sensing brake booster vacuum; a knock sensor for determining ignition of end gases (not shown); a measurement of engine manifold pressure (MAP) from pressure sensor 122 coupled to intake manifold 44 ; an engine position sensor from a Hall effect sensor 118 sensing crankshaft 40 position; a measurement of air mass entering the engine from sensor 120 (e.g., a hot wire air flow meter); and a measurement of throttle position from sensor 58 . Barometric pressure may also be sensed (sensor not shown) for processing by controller 12 . In a preferred aspect of the present description, engine position sensor 118 produces a predetermined number of equally spaced pulses every revolution of the crankshaft from which engine speed (RPM) can be determined. [0018] In some embodiments, the engine may be coupled to an electric motor/battery system in a hybrid vehicle. The hybrid vehicle may have a parallel configuration, series configuration, or variation or combinations thereof. Further, in some embodiments, other engine configurations may be employed, for example a diesel engine. [0019] During operation, each cylinder within engine 10 typically undergoes a four stroke cycle: the cycle includes the intake stroke, compression stroke, expansion stroke, and exhaust stroke. During the intake stroke, generally, the exhaust valve 54 closes and intake valve 52 opens. Air is introduced into combustion chamber 30 via intake manifold 44 , and piston 36 moves to the bottom of the cylinder so as to increase the volume within combustion chamber 30 . The position at which piston 36 is near the bottom of the cylinder and at the end of its stroke (e.g. when combustion chamber 30 is at its largest volume) is typically referred to by those of skill in the art as bottom dead center (BDC). During the compression stroke, intake valve 52 and exhaust valve 54 are closed. Piston 36 moves toward the cylinder head so as to compress the air within combustion chamber 30 . The point at which piston 36 is at the end of its stroke and closest to the cylinder head (e.g. when combustion chamber 30 is at its smallest volume) is typically referred to by those of skill in the art as top dead center (TDC). In a process hereinafter referred to as injection, fuel is introduced into the combustion chamber. In a process hereinafter referred to as ignition, the injected fuel is ignited by known ignition means such as spark plug 92 , resulting in combustion. During the expansion stroke, the expanding gases push piston 36 back to BDC. Crankshaft 40 converts piston movement into a rotational torque of the rotary shaft. Finally, during the exhaust stroke, the exhaust valve 54 opens to release the combusted air-fuel mixture to exhaust manifold 48 and the piston returns to TDC. Note that the above is described merely as an example, and that intake and exhaust valve opening and/or closing timings may vary, such as to provide positive or negative valve overlap, late intake valve closing, or various other examples. [0020] Thus, the system of FIG. 1 provides for an engine vacuum system, comprising: an engine; an electrically driven vacuum pump in fluid communication (e.g., air and oil) with the engine and a vacuum reservoir, a vacuum pump exhaust port of the electrically driven vacuum pump in fluid communication with an interior region of a crankcase or cylinder head valve cover of the engine. The engine vacuum system includes where the electrically driven vacuum pump is located inside the engine. The engine vacuum system includes where the vacuum pump is located external of the engine. The engine vacuum system further comprises a conduit configured to carry engine oil from the engine to the electrically driven vacuum pump. The engine vacuum system further comprises a control valve located along the length of the conduit. The engine vacuum system further comprises a conduit, the conduit coupling the electrically driven vacuum pump to a vacuum reservoir and a check valve. The engine vacuum system further comprises a controller, the controller including instructions to activate and deactivate the electrically driven vacuum pump in response to an air pressure within the vacuum reservoir. The engine vacuum system further comprises additional instructions for judging whether or not to start the vacuum pump during a start of the engine. [0021] The system of FIG. 1 also provides for an engine vacuum system, comprising: an engine; a vacuum pump configured to exhaust pumped air to an interior region of a crankcase or cylinder valve cover of the engine. The engine vacuum system includes where the vacuum pump is an electrically driven vacuum pump lubricated with engine oil. The engine vacuum system further comprises a conduit, the conduit coupling the vacuum pump to an engine oil pump. The engine vacuum system further comprises a controller, the controller including instructions to selectively activate the vacuum pump. The engine vacuum system further comprises a conduit coupling an air output port of the vacuum pump to the crankcase or cylinder valve cover. The engine vacuum system further comprises a conduit coupling an air inlet port of the vacuum pump to a vacuum reservoir or a vacuum consumer (e.g., brake booster or waste gate actuator). [0022] Referring now to FIG. 2 , simulated signals of interest during engine operation are shown. Vertical markers T 0 -T 5 identify particular times of interest during the operating sequence. Similar signals may be observed when the methods of FIGS. 3-4 are executed by controller 12 of FIG. 1 . [0023] The first plot from the top of FIG. 2 shows vacuum reservoir pressure versus time. Time starts at the left side of the plot and increases to the right. Horizontal marker 204 represents a second threshold level of vacuum reservoir pressure. Horizontal marker 206 represents a first threshold level of vacuum reservoir pressure. Vacuum reservoir vacuum is at a higher level of vacuum at the bottom of the plot. The presence of low pressure translates to a high vacuum. [0024] The second plot from the top of FIG. 2 shows engine speed versus time. Time starts at the left side of the plot and increases to the right. Engine speed is at its lowest value at the bottom of the plot and increases toward the top of the plot. Horizontal marker 208 represents a desired engine idle speed. Desired engine idle speed can vary with engine operating conditions such as engine coolant temperature and time since engine start. [0025] The third plot from the top of FIG. 2 shows a vacuum pump control command (e.g. vacuum pump 141 of FIG. 1 ). Time starts at the left side of the plot and increases to the right. The vacuum pump control is on when the signal is near the top of the plot, and the vacuum pump control is off when the signal is near the bottom of the plot. [0026] At time T 0 , vacuum reservoir pressure is at a higher level and is increasing. Vacuum reservoir pressure may increase in response to use of a vacuum operated actuator. For example, vacuum reservoir pressure can increase when vehicle brakes are applied and released. Vacuum reservoir pressure can also increase when vacuum is used to operate a turbocharger waste gate or other vacuum operated actuator. Further, vacuum pressure can also increase when air seeps by check valves or other components that are used to maintain vacuum level. Engine speed is zero at time T 0 and indicates that the engine is not operating. The vacuum pump control command is also at a low level indicating that the vacuum pump is initially turned off. [0027] At time T 1 , vacuum reservoir pressure exceeds the second threshold pressure level 204 of vacuum reservoir pressure. When vacuum reservoir pressure exceeds the second threshold pressure level, the vacuum pump is commanded on. By commanding the vacuum pump on, air is evacuated from the vacuum reservoir so that pressure in the vacuum reservoir can be decreased. Air evacuated from the vacuum reservoir via the vacuum pump is exhausted by the vacuum pump to an interior region of the engine. In one example, air is exhausted from the vacuum pump to the engine crankcase. In another example, air is exhausted from the vacuum pump to the engine under a cylinder head valve cover. The air is exhausted so that it has to first proceed through the engine before reentering the atmosphere. The entrained oil mist is separated from the air via known crankcase ventilation mechanisms. In one example, the air may exit the crankcase and enter the intake air stream via the engine PCV system. In another example, air may exit the crankcase or enclosed area under a valve cover. [0028] Between time T 1 and T 2 , the vacuum pump draws air from the vacuum reservoir. As a result, the pressure in the vacuum reservoir decreases, thereby increasing the vacuum level within the vacuum reservoir. [0029] At time T 2 , pressure in the vacuum reservoir decreases to a level less than first threshold pressure level 206 . When the pressure level of the vacuum reservoir reaches the first threshold pressure level 206 it may be judged that there is a desired level of vacuum so that the vacuum pump can be turned off. Therefore, the vacuum pump is commanded off at time T 2 . Between time T 2 and T 3 , pressure in the vacuum reservoir remains at or below first pressure level 206 . [0030] At time T 3 , the engine begins to rotate and engine speed increases to a low level (e.g., 200 RPM) as the engine is cranked by a starter motor. Cranking the engine does not increase the vacuum reservoir pressure since check valves act to limit flow from the vacuum reservoir. Thus, the vacuum pump does not have to be operated during a particular engine starting sequence. However, as time approaches T 4 , vacuum reservoir pressure begins to increase. The pressure increase may be related to one or more brake application and release events or to operation of another vacuum operated device. [0031] At time T 4 , pressure in the vacuum reservoir reaches the second pressure level 204 while the starter motor continues to crank the engine. Vacuum reservoir pressure reaching second pressure level 204 initiates a request for vacuum and the vacuum pump is turned on. Air is drawn from the vacuum reservoir when the vacuum pump is turned on. The vacuum pump stays on until pressure in the vacuum reservoir reaches the first pressure level 206 at time T 5 . In this particular example, the vacuum pump remains on during cranking and during engine speed run-up (e.g., where engine speed increases from a crank speed to a desired idle speed during engine starting). However, in other examples the vacuum pump may be commanded off while the engine is rotating and below idle speed. The engine may be commanded on when engine speed reaches idle speed. Thus, in some examples, the vacuum pump can be deactivated during an engine start so that the vacuum pump does not affect the alternator load if the vacuum pump is electrically driven. In other examples, the vacuum pump can be activated during or before an engine start so that at least some engine vacuum is available at engine start. [0032] At time T 5 , engine speed has reached and exceeded desired engine idle speed 208 . Pressure in the vacuum reservoir has also been reduced to the first pressure level 206 by the activated vacuum pump. As a result, the vacuum pump is deactivated. [0033] Thus, FIG. 2 shows signals of interest during one example engine starting sequence. The vacuum pump control of FIG. 2 describes one vacuum pump operating sequence before and during an engine start for an electrically actuated vacuum pump. It can be seen that the vacuum pump may provide vacuum to a vacuum reservoir before engine operation. Further, the vacuum pump may be commanded on or off during engine run-up depending on the particular starting strategy. Since the air from the outlet of the vacuum pump is directed to the engine crankcase or into an interior region of the engine bounded by the cylinder head valve covers, engine oil used to wet vacuum pump seals can be directed to areas of the engine where oil can precipitate into the engine oil sump. Consequently, hydrocarbon emissions to the atmosphere can be reduced even when the engine is not operating. [0034] Referring now to FIG. 3 , a high level flowchart for adjusting operation of a vacuum control valve is shown. The method of FIG. 3 is executable by instructions of controller 12 of FIG. 1 . [0035] At 302 , method 300 determines engine operating conditions. Engine operating conditions include but are not limited to engine speed, engine load, vacuum reservoir pressure, engine intake manifold pressure, intake throttle position, brake actuator position, and desired engine torque. Method 300 proceeds to 304 after engine operating conditions are determined. [0036] At 304 , method 300 judges whether or not vacuum is requested. In one example, vacuum may be requested when pressure in a vacuum reservoir is greater than first and second pressure level thresholds. For example, the first pressure level threshold may be a lower pressure threshold where vacuum level pressure is low enough where no additional reduction in vacuum pressure is desired. The second pressure level threshold may be a pressure threshold where when pressure in the vacuum reservoir exceeds the second pressure level threshold additional vacuum is requested. When pressure in the vacuum reservoir is between the first pressure level threshold and the second pressure level threshold, the vacuum pump may remain on or off. If the vacuum pump was shut off due to pressure in the vacuum reservoir being at or below the first pressure level threshold, the vacuum pump remains off until pressure in the vacuum reservoir reaches the second pressure level threshold. If the vacuum pump was turned on due to pressure in the vacuum reservoir being at or above the second pressure level threshold, the vacuum pump remains on until pressure in the vacuum reservoir reaches the first pressure level threshold. If method 300 judges a request for vacuum, method 300 proceeds to 306 . Otherwise, method 300 proceeds to exit. [0037] At 306 , method 300 supplies engine oil to the vacuum pump. In one example, engine oil is supplied from the engine to the vacuum pump via the engine oil pump. In another example, engine oil is supplied to the vacuum pump via gravity feed. A valve may selectively allow engine oil to flow from the engine to the vacuum pump. The engine oil may be supplied to the vacuum pump to lubricate pump bearings and pump seals. A vacuum pump with oil wetted seals may improve vacuum pump efficiency as compared to vacuum pumps with dry seals. The oil may fill gaps in pump seals and may decrease vacuum pump friction. [0038] At 308 , method 300 draws air from a vacuum reservoir. The vacuum reservoir may be a stand-alone reservoir or it may be included with other components such as a vacuum reservoir in a brake booster. The vacuum pump draws air from the vacuum reservoir and thereby increases vacuum within the vacuum system. Method 300 proceeds to 310 as air is drawn from the vacuum reservoir. [0039] At 310 , method 300 exhausts air drawn from the vacuum reservoir via the vacuum pump to interior regions of the engine. In one example, the vacuum pump exhausts air from the vacuum reservoir to the engine crankcase. In another example, the vacuum pump exhausts air from the vacuum reservoir to the interior region of cylinder head valve covers. In other examples, air drawn from the vacuum reservoir may be directed to the engine intake manifold or intake air system. In this way, air drawn from the vacuum reservoir can be pumped into an interior region of the engine so that air does not directly flow to atmosphere. When air is evacuated from a vacuum reservoir and directed to an interior region of the engine, such at the crankcase or cylinder head valve covers, oil entrained in the air may be separated from the air. The air exhausted from the vacuum pump can be subsequently used in combustion of an air-fuel mixture. In this way, hydrocarbons may be processed through the engine and exhaust system to that fewer hydrocarbons may be put into the atmosphere. Method 300 exits after air from the vacuum pump is exhausted to an interior region of the engine. [0040] Referring now to FIG. 4 , a flowchart of a method for operating a vacuum pump during selected engine operating conditions is shown. The method of FIG. 4 is executable by instructions of controller 12 of FIG. 1 . [0041] At 402 , method 400 determines engine operating conditions. Engine operating conditions include but are not limited to engine speed, engine load, vacuum reservoir pressure, engine intake manifold pressure, intake throttle position, brake actuator position, and desired engine torque. Method 400 proceeds to 404 after engine operating conditions are determined. [0042] At 404 , method 400 judges whether or not ignition key-on is present. A key-on condition may be indicated by an assertion of a switch such as an ignition switch or a start engine button. The key-on condition does not have to include engine cranking. However, the key-on condition may be indicative of a future intent to start the vehicle's engine. If method 400 judges no key-on is indicated, method 400 returns to 402 . Otherwise, method 400 proceeds to 406 . [0043] At 406 , method 400 judges whether or not there is a request to crank the engine. An engine crank request may be initiated by a key or other input to a controller, and the engine may be cranked via a starter motor or via an auxiliary motive device. If method 400 judges that there is an engine cranking request, method 400 proceeds to 408 . Otherwise, method 400 proceeds to 422 . [0044] At 422 , method 400 judges whether or not there is sufficient battery power to operate the vacuum pump. In one example, method 400 judges whether or not there is sufficient battery power to operate the vacuum pump based on battery voltage. In other examples, method 400 judges whether or not there is sufficient battery power to operate the vacuum pump based on an estimated battery state of charge. If method 400 judges that there is sufficient battery power to operate the vacuum pump, method 400 proceeds to 424 . Otherwise, method 400 returns to 406 . In this way, method 400 may conserve battery power for starting the engine rather than operating the vacuum pump. [0045] At 424 , method 400 judges whether or not a request for vacuum has been initiated. A vacuum request may be initiated in response to a pressure of a vacuum reservoir greater than a predetermined threshold pressure. In another example, a vacuum request may be initiated by activation or deactivation of a device of a vehicle. For example, a vacuum request may be initiated in response to activation or deactivation of a brake pedal. If vacuum is requested, method 400 proceeds to 426 . Otherwise, method 400 proceeds to 428 . [0046] At 426 , method 400 starts a vacuum pump and opens an engine oil supply to the vacuum pump. In one example, the vacuum pump may be activated via an electrical command such as activating a transistor or relay. The engine oil may be supplied to the vacuum pump by opening an electrically controlled valve. Air begins to be evacuated from a vacuum reservoir and the vacuum system when the vacuum pump is started. The vacuum pump also exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover. Air exhausted by the vacuum pump to an interior region of the engine can be directed to engine cylinders via the PCV system. Removing the hydrocarbons from the air reduces the possibility of transferring hydrocarbons to atmosphere. Method 400 proceeds to 406 after the vacuum pump is started and after opening the engine oil supply to the vacuum pump. [0047] At 428 , the vacuum pump may be shut off or deactivated by opening a switch or a relay. The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve. Deactivating the vacuum pump stops air from being drawn from the vacuum reservoir by the vacuum pump. Method 400 returns to 406 after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed. [0048] At 408 , method 400 judges whether or not there is sufficient battery power to crank the engine and operate the vacuum pump. In one example, method may allow the vacuum pump to operate as long as the battery voltage is greater than a predetermined threshold voltage. If the battery voltage is less than the predetermined threshold voltage before or during engine cranking, the vacuum pump may be commanded off. In other examples, method 400 may judge whether or not there is sufficient battery power to crank the engine and operate the vacuum pump in response to an estimated battery state of charge. If it is judged that there is sufficient battery power to crank the engine and operate the vacuum pump, method 400 proceeds to 410 . Otherwise, method 400 proceeds to 430 . [0049] At 410 , method 400 starts a vacuum pump, opens an engine oil supply to the vacuum pump, and cranks the engine. As described at 426 , the vacuum pump exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover. Further, air begins to be evacuated from a vacuum reservoir and the vacuum system when the vacuum pump is started. The vacuum pump also exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover. Air exhausted by the vacuum pump to an interior region of the engine can be directed to engine cylinders via the PCV system. Method 400 proceeds to 412 after the vacuum pump is started and after opening the engine oil supply to the vacuum pump. [0050] At 430 , the vacuum pump may be shut off or deactivated by opening a switch or a relay. The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve. Deactivating the vacuum pump stops air from being drawn from the vacuum reservoir by the vacuum pump. Method 400 proceeds to 412 after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed. [0051] At 412 , method 400 judges whether or not the engine is started. The engine may be judged to be started after the engine reaches a predetermined engine starting speed. For example, the engine may be determined to be started after a desired engine idle speed is exceeded. If method 400 judges that the engine is started, method 400 proceeds to 414 . Otherwise, method 400 returns to 404 . [0052] At 414 , method 400 judges whether or not vacuum is requested. As discussed at 408 , a vacuum request may be initiated in response to a pressure of a vacuum reservoir greater than a predetermined threshold pressure. If vacuum is requested, method 400 proceeds to 416 . Otherwise, method 400 proceeds to 432 . [0053] At 432 , the vacuum pump may be shut off or deactivated by opening a switch or a relay. The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve. Deactivating the vacuum pump stops air from being drawn from the vacuum reservoir by the vacuum pump. Method 400 proceeds to 418 after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed. [0054] At 416 , method 400 starts a vacuum pump and opens an engine oil supply to the vacuum pump. As described at 426 and 410 , the vacuum pump exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover. Further, air begins to be evacuated from a vacuum reservoir and the vacuum system when the vacuum pump is started. The vacuum pump also exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover. Air exhausted by the vacuum pump to an interior region of the engine can be directed to engine cylinders via the PCV system. Method 400 proceeds to 418 after the vacuum pump is started and after opening the engine oil supply to the vacuum pump. [0055] At 418 , method 400 judges whether or not there is a request to stop the engine. The request may be initiated by an operator or by a system of the vehicle (e.g., a hybrid vehicle controller). If an engine stop request is not present, method 400 proceeds to 414 . Otherwise, method 400 proceeds to 420 . [0056] At 420 , method 400 stops the vacuum pump and closes the engine oil supply to the vacuum pump. The vacuum pump may be shut off or deactivated by opening a switch or a relay. The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve. Method 400 proceeds to exit after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed. [0057] Thus, the method of FIGS. 3-4 provide for a method for providing vacuum, comprising: pumping air from a vacuum reservoir to an interior region of an engine crankcase or an engine valve cover, the vacuum reservoir storing a medium for assisting an operator to apply brakes of a vehicle. The method further comprises routing air from the engine crankcase or engine valve cover to an engine cylinder and combusting a mixture of the air and fuel. The method includes where the air is pumped from the vacuum reservoir via an electrically driven pump. The method includes where the electrically driven pump is activated during a first engine start and deactivated during a second engine start. The method further comprises lubricating a pump with engine oil, the pump including an air inlet port coupled to the vacuum reservoir. The method includes where the electrically driven pump is activated in response to a pressure of the vacuum reservoir greater than a threshold pressure. [0058] As will be appreciated by one of ordinary skill in the art, the methods described in FIGS. 3-4 may represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like. As such, various steps or functions illustrated may be performed in the sequence illustrated, in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily required to achieve the objects, features, and advantages described herein, but is provided for ease of illustration and description. Although not explicitly illustrated, one of ordinary skill in the art will recognize that one or more of the illustrated steps or functions may be repeatedly performed depending on the particular strategy being used. [0059] This concludes the description. The reading of it by those skilled in the art would bring to mind many alterations and modifications without departing from the spirit and the scope of the description. For example, single cylinder, I2, I3, I4, I5, V6, V8, V10, V12 and V16 engines operating in natural gas, gasoline, diesel, or alternative fuel configurations could use the present description to advantage.
An engine with an efficient selectively operable vacuum source is disclosed. In one example, an electric vacuum pump with oil wetted seals provides vacuum to a vehicle. The approach may provide for improved efficiency when generating vacuum.
Identify the most important claim in the given context and summarize it
[ "BACKGROUND/SUMMARY [0001] Vacuum may be used to operate or to assist in the operation of various devices of a vehicle.", "For example, vacuum may be used to assist a driver applying vehicle brakes.", "In some vehicle systems vacuum is provided via a vacuum pump.", "Some vacuum pumps are electrically driven by motors while others are mechanically driven by the vehicle's engine.", "Engine driven vacuum pumps can operate at higher efficiencies than electrically driven vacuum pumps;", "however, operation of mechanically driven vacuum pumps is constrained by engine operation.", "For example, mechanically driven vacuum pumps do not pump air while the engine is not rotating.", "On the other hand, electrically driven vacuum pumps may be activated and deactivated without regard to engine operation so that engine fuel economy can be increased;", "however, electrically driven vacuum pumps can be less efficient than mechanically driven vacuum pumps.", "Thus, opportunities exist to improve on the operation of both electrically and mechanically driven vacuum pumps.", "[0002] The inventor herein has recognized the above-mentioned disadvantages and has developed an engine vacuum system, comprising: an engine;", "an electrically driven vacuum pump in fluid communication with the engine and a vacuum reservoir, a vacuum pump exhaust port of the electrically driven vacuum pump in fluid communication with an interior region of a crankcase or cylinder head valve cover of the engine.", "[0003] By directing the outlet of an electrically driven vacuum pump to an area interior to an engine, it is possible to use engine oil lubricate the mechanism and to wet the pumping chamber seals of an electrically driven pump so that the pump has higher pumping efficiency without increasing vehicle emissions.", "For example, air can be pumped on demand from a vacuum reservoir by an electrically driven vacuum pump to an engine crankcase.", "Oil used to wet seals of the vacuum pump can be deposited into the engine crankcase, and air from the vacuum reservoir can be routed to engine cylinders via a positive crankcase ventilation (PCV) system for participation in combustion of an air-fuel mixture.", "In this way, the pumping efficiency of the electrically driven vacuum pump can be increased without increasing engine emissions.", "In other examples, air exhausted from an engine driven vacuum pump with an oil wetted pumping chamber can be routed to a region of the engine enclosed by a cylinder head valve cover to reduce vehicle emissions.", "The valve covers enclose the valve train and limit the flow of oil and other substances to atmosphere.", "[0004] The present description may provide several advantages.", "In particular, the approach can improve the operation of electrically and engine (mechanically) driven vacuum pumps that have oil wetted seals.", "Further, the approach can reduce vehicle emissions for vehicles that have vacuum pumps.", "Further still, the approach may provide improved vacuum pump control during some conditions.", "[0005] The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.", "[0006] It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description.", "It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description.", "Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.", "BRIEF DESCRIPTION OF THE FIGURES [0007] FIG. 1 shows a schematic depiction of an engine;", "[0008] FIG. 2 shows simulated signals of interest during engine operation;", "[0009] FIG. 3 shows a high level flowchart of a method for operating of a vacuum pump;", "and [0010] FIG. 4 shows a flowchart of a method for operating a vacuum pump during selected engine operating conditions.", "DETAILED DESCRIPTION [0011] The present description is related to producing vacuum for use as a medium to assist in actuator operation.", "FIG. 1 shows one example system for producing vacuum used to assist actuator operation.", "FIG. 2 shows simulated signals of interest when controlling vacuum within a reservoir that supplies power to assist in actuator operation according to the methods of FIGS. 3 and 4 .", "[0012] Referring to FIG. 1 , internal combustion engine 10 , comprising a plurality of cylinders, one cylinder of which is shown in FIG. 1 , is controlled by electronic engine controller 12 .", "Engine 10 includes combustion chamber 30 and cylinder walls 32 with piston 36 positioned therein and connected to crankshaft 40 .", "Combustion chamber 30 is shown communicating with intake manifold 44 and exhaust manifold 48 via respective intake valve 52 and exhaust valve 54 .", "Each intake and exhaust valve may be operated by an intake cam 51 and an exhaust cam 53 .", "Alternatively, one or more of the intake and exhaust valves may be operated by an electromechanically controlled valve coil and armature assembly.", "The position of intake cam 51 may be determined by intake cam sensor 55 .", "The position of exhaust cam 53 may be determined by exhaust cam sensor 57 .", "Intake valve 52 and exhaust valve 54 are enclosed within cylinder head valve cover 38 which may be sealed from atmosphere.", "Crankshaft 40 is located within crankcase 34 as is engine oil pump 146 .", "Engine oil pump supplies engine oil for lubricating intake valve 52 , exhaust valve 54 , intake cam 51 , exhaust cam 53 , and vacuum pump 141 .", "Valve 144 is electrically activated and deactivated by controller 12 and selectively allows oil to flow from engine 10 to vacuum pump 141 .", "In other examples, engine oil may be supplied to vacuum pump 141 via gravity feed.", "For example, oil pump 146 can supply oil to intake cam 51 and exhaust cam 53 .", "Oil may be returned from intake cam 51 and exhaust cam 53 to crankcase 34 through vacuum pump 141 via a conduit (not shown).", "In still other examples, vacuum pumps are capable of drawing their own lubricating and sealing oil from the engine oil sump.", "[0013] Fuel injector 66 is shown positioned to inject fuel directly into cylinder 30 , which is known to those skilled in the art as direct injection.", "Alternatively, fuel may be injected to an intake port, which is known to those skilled in the art as port injection.", "Fuel injector 66 delivers liquid fuel in proportion to the pulse width of signal FPW from controller 12 .", "Fuel is delivered to fuel injector 66 by a fuel system (not shown) including a fuel tank, fuel pump, and fuel rail (not shown).", "Fuel injector 66 is supplied operating current from driver 68 which responds to controller 12 .", "In addition, intake manifold 44 is shown communicating with optional electronic throttle 62 which adjusts a position of throttle plate 64 to control air flow from intake boost chamber 46 to intake manifold 44 .", "[0014] Compressor 162 draws air from air intake 42 to supply boost chamber 46 .", "Exhaust gases spin turbine 164 which is coupled to compressor 162 via shaft 160 .", "Vacuum operated waste gate actuator 72 allows exhaust gases to bypass turbine 164 so that boost pressure can be controlled under varying operating conditions.", "Vacuum is supplied to waste gate actuator 72 via vacuum reservoir 139 by way of a conduit (not shown).", "Vacuum may also be supplied to a vacuum actuated compressor bypass valve.", "Vacuum pump 141 provides vacuum to brake booster 140 via conduit 147 .", "Check valve 149 limits air flow from vacuum pump 141 to brake booster 140 and allows air flow from brake booster 140 to vacuum pump 141 .", "Additional vacuum capacity is provided by vacuum reservoir 139 .", "Brake booster 140 includes an internal vacuum reservoir and it amplifies force provided by foot 152 via brake pedal 150 to master cylinder 148 for applying vehicle brakes (not shown).", "[0015] Distributorless ignition system 88 provides an ignition spark to combustion chamber 30 via spark plug 92 in response to controller 12 .", "Universal Exhaust Gas Oxygen (UEGO) sensor 126 is shown coupled to exhaust manifold 48 upstream of catalytic converter 70 .", "Alternatively, a two-state exhaust gas oxygen sensor may be substituted for UEGO sensor 126 .", "[0016] Converter 70 can include multiple catalyst bricks, in one example.", "In another example, multiple emission control devices, each with multiple bricks, can be used.", "Converter 70 can be a three-way type catalyst in one example.", "[0017] Controller 12 is shown in FIG. 1 as a conventional microcomputer including: microprocessor unit 102 , input/output ports 104 , read-only memory 106 , random access memory 108 , keep alive memory 110 , and a conventional data bus.", "Controller 12 is shown receiving various signals from sensors coupled to engine 10 , in addition to those signals previously discussed, including: engine coolant temperature (ECT) from temperature sensor 112 coupled to cooling sleeve 114 ;", "a position sensor 134 coupled to an accelerator pedal 130 for sensing accelerator position adjusted by foot 132 ;", "a position sensor 154 coupled to brake pedal 150 for sensing brake pedal position, a pressure sensor 142 for sensing brake booster vacuum;", "a knock sensor for determining ignition of end gases (not shown);", "a measurement of engine manifold pressure (MAP) from pressure sensor 122 coupled to intake manifold 44 ;", "an engine position sensor from a Hall effect sensor 118 sensing crankshaft 40 position;", "a measurement of air mass entering the engine from sensor 120 (e.g., a hot wire air flow meter);", "and a measurement of throttle position from sensor 58 .", "Barometric pressure may also be sensed (sensor not shown) for processing by controller 12 .", "In a preferred aspect of the present description, engine position sensor 118 produces a predetermined number of equally spaced pulses every revolution of the crankshaft from which engine speed (RPM) can be determined.", "[0018] In some embodiments, the engine may be coupled to an electric motor/battery system in a hybrid vehicle.", "The hybrid vehicle may have a parallel configuration, series configuration, or variation or combinations thereof.", "Further, in some embodiments, other engine configurations may be employed, for example a diesel engine.", "[0019] During operation, each cylinder within engine 10 typically undergoes a four stroke cycle: the cycle includes the intake stroke, compression stroke, expansion stroke, and exhaust stroke.", "During the intake stroke, generally, the exhaust valve 54 closes and intake valve 52 opens.", "Air is introduced into combustion chamber 30 via intake manifold 44 , and piston 36 moves to the bottom of the cylinder so as to increase the volume within combustion chamber 30 .", "The position at which piston 36 is near the bottom of the cylinder and at the end of its stroke (e.g. when combustion chamber 30 is at its largest volume) is typically referred to by those of skill in the art as bottom dead center (BDC).", "During the compression stroke, intake valve 52 and exhaust valve 54 are closed.", "Piston 36 moves toward the cylinder head so as to compress the air within combustion chamber 30 .", "The point at which piston 36 is at the end of its stroke and closest to the cylinder head (e.g. when combustion chamber 30 is at its smallest volume) is typically referred to by those of skill in the art as top dead center (TDC).", "In a process hereinafter referred to as injection, fuel is introduced into the combustion chamber.", "In a process hereinafter referred to as ignition, the injected fuel is ignited by known ignition means such as spark plug 92 , resulting in combustion.", "During the expansion stroke, the expanding gases push piston 36 back to BDC.", "Crankshaft 40 converts piston movement into a rotational torque of the rotary shaft.", "Finally, during the exhaust stroke, the exhaust valve 54 opens to release the combusted air-fuel mixture to exhaust manifold 48 and the piston returns to TDC.", "Note that the above is described merely as an example, and that intake and exhaust valve opening and/or closing timings may vary, such as to provide positive or negative valve overlap, late intake valve closing, or various other examples.", "[0020] Thus, the system of FIG. 1 provides for an engine vacuum system, comprising: an engine;", "an electrically driven vacuum pump in fluid communication (e.g., air and oil) with the engine and a vacuum reservoir, a vacuum pump exhaust port of the electrically driven vacuum pump in fluid communication with an interior region of a crankcase or cylinder head valve cover of the engine.", "The engine vacuum system includes where the electrically driven vacuum pump is located inside the engine.", "The engine vacuum system includes where the vacuum pump is located external of the engine.", "The engine vacuum system further comprises a conduit configured to carry engine oil from the engine to the electrically driven vacuum pump.", "The engine vacuum system further comprises a control valve located along the length of the conduit.", "The engine vacuum system further comprises a conduit, the conduit coupling the electrically driven vacuum pump to a vacuum reservoir and a check valve.", "The engine vacuum system further comprises a controller, the controller including instructions to activate and deactivate the electrically driven vacuum pump in response to an air pressure within the vacuum reservoir.", "The engine vacuum system further comprises additional instructions for judging whether or not to start the vacuum pump during a start of the engine.", "[0021] The system of FIG. 1 also provides for an engine vacuum system, comprising: an engine;", "a vacuum pump configured to exhaust pumped air to an interior region of a crankcase or cylinder valve cover of the engine.", "The engine vacuum system includes where the vacuum pump is an electrically driven vacuum pump lubricated with engine oil.", "The engine vacuum system further comprises a conduit, the conduit coupling the vacuum pump to an engine oil pump.", "The engine vacuum system further comprises a controller, the controller including instructions to selectively activate the vacuum pump.", "The engine vacuum system further comprises a conduit coupling an air output port of the vacuum pump to the crankcase or cylinder valve cover.", "The engine vacuum system further comprises a conduit coupling an air inlet port of the vacuum pump to a vacuum reservoir or a vacuum consumer (e.g., brake booster or waste gate actuator).", "[0022] Referring now to FIG. 2 , simulated signals of interest during engine operation are shown.", "Vertical markers T 0 -T 5 identify particular times of interest during the operating sequence.", "Similar signals may be observed when the methods of FIGS. 3-4 are executed by controller 12 of FIG. 1 .", "[0023] The first plot from the top of FIG. 2 shows vacuum reservoir pressure versus time.", "Time starts at the left side of the plot and increases to the right.", "Horizontal marker 204 represents a second threshold level of vacuum reservoir pressure.", "Horizontal marker 206 represents a first threshold level of vacuum reservoir pressure.", "Vacuum reservoir vacuum is at a higher level of vacuum at the bottom of the plot.", "The presence of low pressure translates to a high vacuum.", "[0024] The second plot from the top of FIG. 2 shows engine speed versus time.", "Time starts at the left side of the plot and increases to the right.", "Engine speed is at its lowest value at the bottom of the plot and increases toward the top of the plot.", "Horizontal marker 208 represents a desired engine idle speed.", "Desired engine idle speed can vary with engine operating conditions such as engine coolant temperature and time since engine start.", "[0025] The third plot from the top of FIG. 2 shows a vacuum pump control command (e.g. vacuum pump 141 of FIG. 1 ).", "Time starts at the left side of the plot and increases to the right.", "The vacuum pump control is on when the signal is near the top of the plot, and the vacuum pump control is off when the signal is near the bottom of the plot.", "[0026] At time T 0 , vacuum reservoir pressure is at a higher level and is increasing.", "Vacuum reservoir pressure may increase in response to use of a vacuum operated actuator.", "For example, vacuum reservoir pressure can increase when vehicle brakes are applied and released.", "Vacuum reservoir pressure can also increase when vacuum is used to operate a turbocharger waste gate or other vacuum operated actuator.", "Further, vacuum pressure can also increase when air seeps by check valves or other components that are used to maintain vacuum level.", "Engine speed is zero at time T 0 and indicates that the engine is not operating.", "The vacuum pump control command is also at a low level indicating that the vacuum pump is initially turned off.", "[0027] At time T 1 , vacuum reservoir pressure exceeds the second threshold pressure level 204 of vacuum reservoir pressure.", "When vacuum reservoir pressure exceeds the second threshold pressure level, the vacuum pump is commanded on.", "By commanding the vacuum pump on, air is evacuated from the vacuum reservoir so that pressure in the vacuum reservoir can be decreased.", "Air evacuated from the vacuum reservoir via the vacuum pump is exhausted by the vacuum pump to an interior region of the engine.", "In one example, air is exhausted from the vacuum pump to the engine crankcase.", "In another example, air is exhausted from the vacuum pump to the engine under a cylinder head valve cover.", "The air is exhausted so that it has to first proceed through the engine before reentering the atmosphere.", "The entrained oil mist is separated from the air via known crankcase ventilation mechanisms.", "In one example, the air may exit the crankcase and enter the intake air stream via the engine PCV system.", "In another example, air may exit the crankcase or enclosed area under a valve cover.", "[0028] Between time T 1 and T 2 , the vacuum pump draws air from the vacuum reservoir.", "As a result, the pressure in the vacuum reservoir decreases, thereby increasing the vacuum level within the vacuum reservoir.", "[0029] At time T 2 , pressure in the vacuum reservoir decreases to a level less than first threshold pressure level 206 .", "When the pressure level of the vacuum reservoir reaches the first threshold pressure level 206 it may be judged that there is a desired level of vacuum so that the vacuum pump can be turned off.", "Therefore, the vacuum pump is commanded off at time T 2 .", "Between time T 2 and T 3 , pressure in the vacuum reservoir remains at or below first pressure level 206 .", "[0030] At time T 3 , the engine begins to rotate and engine speed increases to a low level (e.g., 200 RPM) as the engine is cranked by a starter motor.", "Cranking the engine does not increase the vacuum reservoir pressure since check valves act to limit flow from the vacuum reservoir.", "Thus, the vacuum pump does not have to be operated during a particular engine starting sequence.", "However, as time approaches T 4 , vacuum reservoir pressure begins to increase.", "The pressure increase may be related to one or more brake application and release events or to operation of another vacuum operated device.", "[0031] At time T 4 , pressure in the vacuum reservoir reaches the second pressure level 204 while the starter motor continues to crank the engine.", "Vacuum reservoir pressure reaching second pressure level 204 initiates a request for vacuum and the vacuum pump is turned on.", "Air is drawn from the vacuum reservoir when the vacuum pump is turned on.", "The vacuum pump stays on until pressure in the vacuum reservoir reaches the first pressure level 206 at time T 5 .", "In this particular example, the vacuum pump remains on during cranking and during engine speed run-up (e.g., where engine speed increases from a crank speed to a desired idle speed during engine starting).", "However, in other examples the vacuum pump may be commanded off while the engine is rotating and below idle speed.", "The engine may be commanded on when engine speed reaches idle speed.", "Thus, in some examples, the vacuum pump can be deactivated during an engine start so that the vacuum pump does not affect the alternator load if the vacuum pump is electrically driven.", "In other examples, the vacuum pump can be activated during or before an engine start so that at least some engine vacuum is available at engine start.", "[0032] At time T 5 , engine speed has reached and exceeded desired engine idle speed 208 .", "Pressure in the vacuum reservoir has also been reduced to the first pressure level 206 by the activated vacuum pump.", "As a result, the vacuum pump is deactivated.", "[0033] Thus, FIG. 2 shows signals of interest during one example engine starting sequence.", "The vacuum pump control of FIG. 2 describes one vacuum pump operating sequence before and during an engine start for an electrically actuated vacuum pump.", "It can be seen that the vacuum pump may provide vacuum to a vacuum reservoir before engine operation.", "Further, the vacuum pump may be commanded on or off during engine run-up depending on the particular starting strategy.", "Since the air from the outlet of the vacuum pump is directed to the engine crankcase or into an interior region of the engine bounded by the cylinder head valve covers, engine oil used to wet vacuum pump seals can be directed to areas of the engine where oil can precipitate into the engine oil sump.", "Consequently, hydrocarbon emissions to the atmosphere can be reduced even when the engine is not operating.", "[0034] Referring now to FIG. 3 , a high level flowchart for adjusting operation of a vacuum control valve is shown.", "The method of FIG. 3 is executable by instructions of controller 12 of FIG. 1 .", "[0035] At 302 , method 300 determines engine operating conditions.", "Engine operating conditions include but are not limited to engine speed, engine load, vacuum reservoir pressure, engine intake manifold pressure, intake throttle position, brake actuator position, and desired engine torque.", "Method 300 proceeds to 304 after engine operating conditions are determined.", "[0036] At 304 , method 300 judges whether or not vacuum is requested.", "In one example, vacuum may be requested when pressure in a vacuum reservoir is greater than first and second pressure level thresholds.", "For example, the first pressure level threshold may be a lower pressure threshold where vacuum level pressure is low enough where no additional reduction in vacuum pressure is desired.", "The second pressure level threshold may be a pressure threshold where when pressure in the vacuum reservoir exceeds the second pressure level threshold additional vacuum is requested.", "When pressure in the vacuum reservoir is between the first pressure level threshold and the second pressure level threshold, the vacuum pump may remain on or off.", "If the vacuum pump was shut off due to pressure in the vacuum reservoir being at or below the first pressure level threshold, the vacuum pump remains off until pressure in the vacuum reservoir reaches the second pressure level threshold.", "If the vacuum pump was turned on due to pressure in the vacuum reservoir being at or above the second pressure level threshold, the vacuum pump remains on until pressure in the vacuum reservoir reaches the first pressure level threshold.", "If method 300 judges a request for vacuum, method 300 proceeds to 306 .", "Otherwise, method 300 proceeds to exit.", "[0037] At 306 , method 300 supplies engine oil to the vacuum pump.", "In one example, engine oil is supplied from the engine to the vacuum pump via the engine oil pump.", "In another example, engine oil is supplied to the vacuum pump via gravity feed.", "A valve may selectively allow engine oil to flow from the engine to the vacuum pump.", "The engine oil may be supplied to the vacuum pump to lubricate pump bearings and pump seals.", "A vacuum pump with oil wetted seals may improve vacuum pump efficiency as compared to vacuum pumps with dry seals.", "The oil may fill gaps in pump seals and may decrease vacuum pump friction.", "[0038] At 308 , method 300 draws air from a vacuum reservoir.", "The vacuum reservoir may be a stand-alone reservoir or it may be included with other components such as a vacuum reservoir in a brake booster.", "The vacuum pump draws air from the vacuum reservoir and thereby increases vacuum within the vacuum system.", "Method 300 proceeds to 310 as air is drawn from the vacuum reservoir.", "[0039] At 310 , method 300 exhausts air drawn from the vacuum reservoir via the vacuum pump to interior regions of the engine.", "In one example, the vacuum pump exhausts air from the vacuum reservoir to the engine crankcase.", "In another example, the vacuum pump exhausts air from the vacuum reservoir to the interior region of cylinder head valve covers.", "In other examples, air drawn from the vacuum reservoir may be directed to the engine intake manifold or intake air system.", "In this way, air drawn from the vacuum reservoir can be pumped into an interior region of the engine so that air does not directly flow to atmosphere.", "When air is evacuated from a vacuum reservoir and directed to an interior region of the engine, such at the crankcase or cylinder head valve covers, oil entrained in the air may be separated from the air.", "The air exhausted from the vacuum pump can be subsequently used in combustion of an air-fuel mixture.", "In this way, hydrocarbons may be processed through the engine and exhaust system to that fewer hydrocarbons may be put into the atmosphere.", "Method 300 exits after air from the vacuum pump is exhausted to an interior region of the engine.", "[0040] Referring now to FIG. 4 , a flowchart of a method for operating a vacuum pump during selected engine operating conditions is shown.", "The method of FIG. 4 is executable by instructions of controller 12 of FIG. 1 .", "[0041] At 402 , method 400 determines engine operating conditions.", "Engine operating conditions include but are not limited to engine speed, engine load, vacuum reservoir pressure, engine intake manifold pressure, intake throttle position, brake actuator position, and desired engine torque.", "Method 400 proceeds to 404 after engine operating conditions are determined.", "[0042] At 404 , method 400 judges whether or not ignition key-on is present.", "A key-on condition may be indicated by an assertion of a switch such as an ignition switch or a start engine button.", "The key-on condition does not have to include engine cranking.", "However, the key-on condition may be indicative of a future intent to start the vehicle's engine.", "If method 400 judges no key-on is indicated, method 400 returns to 402 .", "Otherwise, method 400 proceeds to 406 .", "[0043] At 406 , method 400 judges whether or not there is a request to crank the engine.", "An engine crank request may be initiated by a key or other input to a controller, and the engine may be cranked via a starter motor or via an auxiliary motive device.", "If method 400 judges that there is an engine cranking request, method 400 proceeds to 408 .", "Otherwise, method 400 proceeds to 422 .", "[0044] At 422 , method 400 judges whether or not there is sufficient battery power to operate the vacuum pump.", "In one example, method 400 judges whether or not there is sufficient battery power to operate the vacuum pump based on battery voltage.", "In other examples, method 400 judges whether or not there is sufficient battery power to operate the vacuum pump based on an estimated battery state of charge.", "If method 400 judges that there is sufficient battery power to operate the vacuum pump, method 400 proceeds to 424 .", "Otherwise, method 400 returns to 406 .", "In this way, method 400 may conserve battery power for starting the engine rather than operating the vacuum pump.", "[0045] At 424 , method 400 judges whether or not a request for vacuum has been initiated.", "A vacuum request may be initiated in response to a pressure of a vacuum reservoir greater than a predetermined threshold pressure.", "In another example, a vacuum request may be initiated by activation or deactivation of a device of a vehicle.", "For example, a vacuum request may be initiated in response to activation or deactivation of a brake pedal.", "If vacuum is requested, method 400 proceeds to 426 .", "Otherwise, method 400 proceeds to 428 .", "[0046] At 426 , method 400 starts a vacuum pump and opens an engine oil supply to the vacuum pump.", "In one example, the vacuum pump may be activated via an electrical command such as activating a transistor or relay.", "The engine oil may be supplied to the vacuum pump by opening an electrically controlled valve.", "Air begins to be evacuated from a vacuum reservoir and the vacuum system when the vacuum pump is started.", "The vacuum pump also exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover.", "Air exhausted by the vacuum pump to an interior region of the engine can be directed to engine cylinders via the PCV system.", "Removing the hydrocarbons from the air reduces the possibility of transferring hydrocarbons to atmosphere.", "Method 400 proceeds to 406 after the vacuum pump is started and after opening the engine oil supply to the vacuum pump.", "[0047] At 428 , the vacuum pump may be shut off or deactivated by opening a switch or a relay.", "The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve.", "Deactivating the vacuum pump stops air from being drawn from the vacuum reservoir by the vacuum pump.", "Method 400 returns to 406 after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed.", "[0048] At 408 , method 400 judges whether or not there is sufficient battery power to crank the engine and operate the vacuum pump.", "In one example, method may allow the vacuum pump to operate as long as the battery voltage is greater than a predetermined threshold voltage.", "If the battery voltage is less than the predetermined threshold voltage before or during engine cranking, the vacuum pump may be commanded off.", "In other examples, method 400 may judge whether or not there is sufficient battery power to crank the engine and operate the vacuum pump in response to an estimated battery state of charge.", "If it is judged that there is sufficient battery power to crank the engine and operate the vacuum pump, method 400 proceeds to 410 .", "Otherwise, method 400 proceeds to 430 .", "[0049] At 410 , method 400 starts a vacuum pump, opens an engine oil supply to the vacuum pump, and cranks the engine.", "As described at 426 , the vacuum pump exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover.", "Further, air begins to be evacuated from a vacuum reservoir and the vacuum system when the vacuum pump is started.", "The vacuum pump also exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover.", "Air exhausted by the vacuum pump to an interior region of the engine can be directed to engine cylinders via the PCV system.", "Method 400 proceeds to 412 after the vacuum pump is started and after opening the engine oil supply to the vacuum pump.", "[0050] At 430 , the vacuum pump may be shut off or deactivated by opening a switch or a relay.", "The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve.", "Deactivating the vacuum pump stops air from being drawn from the vacuum reservoir by the vacuum pump.", "Method 400 proceeds to 412 after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed.", "[0051] At 412 , method 400 judges whether or not the engine is started.", "The engine may be judged to be started after the engine reaches a predetermined engine starting speed.", "For example, the engine may be determined to be started after a desired engine idle speed is exceeded.", "If method 400 judges that the engine is started, method 400 proceeds to 414 .", "Otherwise, method 400 returns to 404 .", "[0052] At 414 , method 400 judges whether or not vacuum is requested.", "As discussed at 408 , a vacuum request may be initiated in response to a pressure of a vacuum reservoir greater than a predetermined threshold pressure.", "If vacuum is requested, method 400 proceeds to 416 .", "Otherwise, method 400 proceeds to 432 .", "[0053] At 432 , the vacuum pump may be shut off or deactivated by opening a switch or a relay.", "The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve.", "Deactivating the vacuum pump stops air from being drawn from the vacuum reservoir by the vacuum pump.", "Method 400 proceeds to 418 after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed.", "[0054] At 416 , method 400 starts a vacuum pump and opens an engine oil supply to the vacuum pump.", "As described at 426 and 410 , the vacuum pump exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover.", "Further, air begins to be evacuated from a vacuum reservoir and the vacuum system when the vacuum pump is started.", "The vacuum pump also exhausts the air to an interior region of the engine such as the crankcase or interior of the cylinder head valve cover.", "Air exhausted by the vacuum pump to an interior region of the engine can be directed to engine cylinders via the PCV system.", "Method 400 proceeds to 418 after the vacuum pump is started and after opening the engine oil supply to the vacuum pump.", "[0055] At 418 , method 400 judges whether or not there is a request to stop the engine.", "The request may be initiated by an operator or by a system of the vehicle (e.g., a hybrid vehicle controller).", "If an engine stop request is not present, method 400 proceeds to 414 .", "Otherwise, method 400 proceeds to 420 .", "[0056] At 420 , method 400 stops the vacuum pump and closes the engine oil supply to the vacuum pump.", "The vacuum pump may be shut off or deactivated by opening a switch or a relay.", "The engine oil supply may be closed to the vacuum pump by closing an electrically controlled valve.", "Method 400 proceeds to exit after the vacuum pump is deactivated and the engine oil supply to the vacuum pump is closed.", "[0057] Thus, the method of FIGS. 3-4 provide for a method for providing vacuum, comprising: pumping air from a vacuum reservoir to an interior region of an engine crankcase or an engine valve cover, the vacuum reservoir storing a medium for assisting an operator to apply brakes of a vehicle.", "The method further comprises routing air from the engine crankcase or engine valve cover to an engine cylinder and combusting a mixture of the air and fuel.", "The method includes where the air is pumped from the vacuum reservoir via an electrically driven pump.", "The method includes where the electrically driven pump is activated during a first engine start and deactivated during a second engine start.", "The method further comprises lubricating a pump with engine oil, the pump including an air inlet port coupled to the vacuum reservoir.", "The method includes where the electrically driven pump is activated in response to a pressure of the vacuum reservoir greater than a threshold pressure.", "[0058] As will be appreciated by one of ordinary skill in the art, the methods described in FIGS. 3-4 may represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like.", "As such, various steps or functions illustrated may be performed in the sequence illustrated, in parallel, or in some cases omitted.", "Likewise, the order of processing is not necessarily required to achieve the objects, features, and advantages described herein, but is provided for ease of illustration and description.", "Although not explicitly illustrated, one of ordinary skill in the art will recognize that one or more of the illustrated steps or functions may be repeatedly performed depending on the particular strategy being used.", "[0059] This concludes the description.", "The reading of it by those skilled in the art would bring to mind many alterations and modifications without departing from the spirit and the scope of the description.", "For example, single cylinder, I2, I3, I4, I5, V6, V8, V10, V12 and V16 engines operating in natural gas, gasoline, diesel, or alternative fuel configurations could use the present description to advantage." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. application Ser. No. 09/764,441, filed Jan. 19, 2001, which claims priority to Canadian Application No. 2296579, filed Jan. 20, 2000. FIELD OF THE INVENTION The present invention relates to apparatuses and processes for cooling beverages and more particularly to a portable coolers having provision for reducing or eliminating the formation of foam in carbonated beverages. BACKGROUND OF THE INVENTION There are numerous events and activities where one desires to enjoy cool beverages. However, many such events and activities are located in places where there is no access to cool beverages chilled by traditionally means such as refrigerators. In particular, remote locations such as on the golf courses, sporting events, outdoor concerts and other outdoor activities, do not facilitate the easy distribution of cool beverages. Easy distribution of cool beverages is also desirable at resorts, bars and restaurants. Most consumers at these activities desire cool beverages. Numerous means have been developed to provide such beverages. There exists in the prior art inventions which have a similar purpose as the subject invention. In particular U.S. Pat. No. 4,225,059 describes a portable beverage cooler and dispenser. The apparatus includes an air cylinder for pressurizing beer kegs. The beer kegs are located in a housing. The beer kegs are connected to a coiled dispensing hose also located in the housing. The hose passes through ice located in ice chambers. This serves to cool the beer before it is dispensed through spigots at the top of the apparatus. In addition, U.S. Pat. No. 2,223,152 describes a stationary beer cooling device. The device is not pressurized. The device cools the beer by circulating it through a cooling coil which is immersed in an ice water bath. The cooling coil is protected by a perforated metal sleeve so as to permit an operator to agitate the ice bath with a stick or a rod. The drawback to both of these inventions is that they do not adequately cool and de-foam beer. The most typical manner to provide cool beverages at remote locations is to transport canned beverages in coolers containing ice and distribute the canned beverages at the remote location. However, the use of canned beverages is more costly to the consumer and creates significant waste in the form of emptied cans. Further, the use of individual cans reduces the volume of beverage one is able to transport to such remote locations since the can packaging occupies the limited cooler space. To address the problems associated with canned beverages there have been attempts to use kegs or other such large vessels to distribute cool beverages at remote locations. However, this method also has drawbacks. It is difficult to cool large vessels so that the beverages are of an acceptable temperature. Further, portable containers are often subject to severe agitation when they are traveling over hilly or rough terrain such as golf courses. A combination of elevated temperature and agitation causes the beverages to form foam. If the beverage is beer, the beer which discharges from the container will be in the form of foam. This ruins the taste of the beverage and makes it impossible to pour the beer properly due to excess foaming. Since most beverages enjoyed by consumers are carbonated, minimizing foaming is of critical importance. When gas that is dissolved in a carbonated beverage leaves the liquid, it creates foam. The foam is often waste and is poured off before the beverage is served. If a carbonated beverage is not handled properly, 50% can be lost to foam waste. Further, even that portion of the carbonated beverage that does not foam will likely be of poor quality since the loss of carbonation will make the beverage less acidic or “flat”. Because the solubility of a gas in a liquid is higher at lower temperatures, the carbon dioxide gas is less likely to come out of solution and form foam at cooler temperatures. Accordingly, it is desirable to dispense carbonated beverages at cool temperatures. Another means to minimize foaming is to maintain the carbonated beverage under a certain amount of pressure. This is true because the solubility of a gas in a liquid is higher at elevated pressures. When the pressure on a carbonated beverage is released or reduced the gas dissolved therein leaves solution more readily and creates foam. Pressure can be maintained on carbonated beverages up to the point of dispensing it by forcing the beverage through a length of conduit of a lesser diameter than the conduit from which it was dispensed from the holding vessel. A significant portion of foam which is present at the time the carbonated beverage is dispensed from the vessel will be reabsorbed by the carbonated beverage by the time it is dispensed for the consumer. However, neither the cooling or pressurization of the carbonated beverage alone is sufficient to satisfactorily reduce foam. The prior art does not describe an apparatus or process, of a portable nature, which provides for the dispensing of cooled, non-foamed carbonated beverages in an economical manner. Therefore there is a need for such apparatuses and processes. SUMMARY OF THE INVENTION The present invention relates to an apparatus for cooling a carbonated beverage from a keg and for continuously delivering non-foamed carbonated beverage. The apparatus includes a conduit that is attachable to the keg and which has a varying diameter. The conduit is submerged in a cooling fluid that is agitated by agitators to flow over the conduit for heat exchange. The agitators are positioned to provide an advantageous flow pattern over the conduit. According to one aspect of the present invention there is provided an apparatus for cooling a carbonated beverage stored in a container and dispensing non-foamed carbonated beverage, the apparatus comprising: a housing defining a chamber having first and second openings; means attached to the container for maintaining the beverage under pressure in said container; a conduit located in the chamber, the conduit communicating with the container through said first opening, the conduit further communicating with the second opening for delivering said beverage from the chamber; cooling fluid located in said chamber for cooling the conduit; and at least two agitators for circulating the cooling fluid over the conduit, the at least two agitators being mounted in the chamber at opposing ends of the chamber and being laterally spaced. According to another aspect of the present invention there is provided an apparatus for cooling a carbonated beverage stored in a container and dispensing non-foamed carbonated beverage, the apparatus comprising: a housing defining a chamber having first and second openings; pressurizing means attached to the container for maintaining the beverage under pressure in said container; a conduit located in the chamber, the conduit communicating with the container through said first opening, the conduit further communicating with the second opening for delivering said beverage from the chamber; a perforated vessel mounted in the chamber, said perforated vessel surrounding the conduit; cooling fluid located in said chamber for cooling the conduit, the cooling fluid including solid fragments, said fragments being substantially larger than the perforations in said vessel; an agitator for circulating the cooling fluid over the conduit; and a pressure valve located between the conduit and the container for detecting a predetermined pressure rating in said container. According to another aspect of the present invention there is provided an apparatus for cooling a carbonated beverage stored in a container and dispensing non-foamed carbonated beverage, the apparatus comprising: a housing defining a chamber having first and second openings; means attached to the container for maintaining the beverage under pressure in said container; a conduit located in the chamber, the conduit communicating with the container through said first opening, the conduit further communicating with the second opening for delivering said beverage from the chamber, the conduit having a length of substantially at least 70 feet and having regions of decreased inner diameter at regions at substantially 5 feet and at substantially 65 feet along said length; cooling fluid located in said chamber for cooling the conduit; and an agitator for circulating the cooling fluid over the conduit. According to yet another aspect of the present invention there is provided a method of cooling a carbonated beverage and continuously delivering non-foamed a carbonated beverage, the method comprising the following steps: providing a conduit having regions of decreased inner diameter for delivering the beverage from the container; pressurizing the beverage in the container to induce flow of the beverage into the conduit; providing a cooling fluid; agitating the cooling fluid to continuously flow over the conduit; and delivering the beverage through the regions of decreased inner diameter to entrain carbon dioxide gas into the beverage. DESCRIPTION OF THE DRAWINGS The invention is described with reference to the accompanying drawings in which: FIG. 1 is a perspective view of a first embodiment of the present invention mounted on a trailer; FIG. 2 is a perspective view, partly cut away, of a cooling coil of the first embodiment; FIG. 3 is a side view, cut away and enlarged scale, of a portion of the cooling coil of the first embodiment; FIG. 4 is a cross-section of the coil of the first embodiment. FIG. 5 is an exploded view of the housing of the second embodiment; FIG. 6 is a perspective view of the coil of the second embodiment; FIG. 7 is a perspective view with portions cut away of the agitators of the second embodiment; FIG. 8 is a perspective view with portions cut away of the perforated vessel surrounding the cooling coil of the second embodiment; FIG. 9 is a perspective view of the housing of the second embodiment; FIG. 10 is a perspective view of the housing of the second embodiment; FIG. 11 is a plan view of the housing of the second embodiment; FIG. 12 is a perspective view with portions cut away of the coil and an agitator of the second embodiment; FIG. 13 is a cross section of the coil and the perforated vessel of the second embodiment; FIG. 14 is a detailed view of the coil assembly of the second embodiment; and FIG. 15 is an exploded view of the coil assembly of the second embodiment. Like reference characters refer to like parts throughout the description of the drawings. DESCRIPTION OF PREFERRED EMBODIMENTS The description which follows is of an apparatus for cooling and dispensing beer but it is to be understood that the apparatus of the invention is not limited to one for cooling and dispensing beer. The apparatus can be used to cool and dispense other carbonated beverages such as non-alcoholic and alcoholic drinks. The apparatus can for example be used to dispense carbonated soft drinks and spritzers. FIGS. 1-4 show a first embodiment of the present invention. With reference to FIG. 1, a trailer 10 holds a keg 14 , a cooler 16 and a tap 18 from which beverage within the keg and cooler discharge. The keg 14 contains beer which flows through a hose 20 to the cooler where it is chilled. From the cooler, the beer flows through a second hose 22 to the tap 18 from which it discharges. Preferably hoses 20 and 22 are composed of braided polyvinyl chloride. The trailer 10 is mounted on wheels 24 so that it can be towed by a motorized golf cart 26 . The keg 14 can be removed from the trailer when it is empty and replaced by another full keg. Beer within the keg 14 is maintained under pressure by means of so called “beer gas” stored in a conventional pneumatic or gas cylinder 30 . Beer gas is usually composed of from about 65 to 75 percent nitrogen and the remainder carbon dioxide. The gas is introduced into the interior of the keg 14 through a hose 32 which extends from the cylinder to the keg. A nozzle and pressure gauge (not illustrated) both of conventional construction are provided in the gas line so that the pressure within the keg can be monitored and controlled. A compressor can also be used. With reference to FIG. 2, a conduit or coil 40 extends through the cooler 16 . The coil has a point of entry 40 a at which beer enters the coil. From the point of entry, the beer enters an upstream segment 40 b and from the upstream segment, the beer flows to a downstream segment 40 c. The inner diameter of the coil decreases downstream of the flow of beer. In FIG. 3 the inner wall of the coil diminishes gradually but the decrease may be abrupt. In the latter event, the inner diameter of the upstream segment is greater than that of the downstream segment. The two segments may be interconnected by a joint of conventional construction. Preferably, the two segments of the coil are composed of stainless steel and each has a constant inner diameter. The inner diameter of the coil at the point of entry 40 a is about ⅜ inch as is that of hose 20 through which the beer flows to the cooler from the keg. The upstream segment 40 b has an inner diameter of about ¼ inch while the downstream segment has an inner diameter of {fraction (3/16)} inch. The upstream segment should be about 60 to about 70 feet in length measured along the longitudinal axis of the coil. Any shorter than 60 feet and the volume of beer at the desired temperature will diminish while any longer than 70 feet, while permissible, will necessitate a higher pressure of beer gas to cause the beer to flow at a satisfactory rate. The preferred pressure of beer gas is about 45 to 55 p.s.i. The pressure of beer gas is most preferably 47 p.s.i. The downstream segment should be about 3 feet in length measured along the longitudinal axis of the coil. Significantly longer and the flow of beer will diminish to a trickle and significantly shorter and foaming becomes a problem. The downstream segment terminates at the tap and accordingly it will straighten at 40 d at its downstream end. While it is desirable that the downstream segment be substantially entirely within the cooler, the apparatus will still work if the downstream segment is partly within and partly outside the cooler. With reference to FIGS. 2 and 4, the coil is mounted within a perforated vessel or cylinder 50 which is closed at both ends 52 , 54 . The cylinder is mounted within cooler 16 which has solid sides and end walls. The cooler contains water and particles of ice 56 which serve to cool the beer within the coil. A drain (not illustrated) is provided at the bottom of the cooler through which the water can be drawn off. A faucet (not illustrated) is provided in the discharge line for controlling the flow from the drain. An opening (not illustrated) is formed on the top of cooler for admission of fresh water and ice particles. The opening is closed by a lid (not illustrated) for preventing the contents of the vessel from spilling out when the trailer is moving. Two submersible pumps 60 , 62 are mounted within the vessel to cause the water to circulate. The water circulates freely around the pumps but the ice particles are prevented from contacting and damaging the pump because they are too large to penetrate through the perforations 64 in cylinder 50 . A pump suitable for causing the water and ice particles to circulate is submersible pump model V500 no. 4204 sold by Attwood Company. The pump is powered by a 12 volt battery. The battery is mounted on the trailer so that the trailer is completely portable and self-contained. With reference to FIG. 1, cooled beer flows from the coil to tap 18 . The tap is of conventional construction and is spring-loaded closed. Such a tap ensures that pressure within the line through which beer flows is maintained at the desired value at all times except when the tap is opened to dispense beer. The beer cooler described above is capable of cooling beer from ambient temperature to a temperature in the range of about 32 to 34 degrees F. This is the range generally favoured by most consumers of beer brewed in North America. Thus the temperature of the beer in the keg will be ambient while the temperature at tap 18 will be about 32 to about 34 degrees. The conditions which have an effect on the amount of foam which discharges from the tap are as follows: 1. The pressure of gas within the keg. The pressure should be maintained at about 45 to 55 p.s.i, preferably 47 p.s.i. The gauge which measures the pressure within the keg should be monitored to ensure that the pressure remains within this range. It is believed that if the pressure is below this range, carbon dioxide in the beer comes out of solution and combines with beer as foam. If the pressure is above this range, the keg must be constructed of heavier and stronger material at added cost and with no significant benefit. 2. The inner diameter of the coil. The diameter must decrease as the beer flows downstream. As indicated above the inner diameter of the coil at the point of entry into the perforated cylinder 50 should preferably be about ¼ inch and at the point of exit from the cylinder about {fraction (3/16)} inch. 3. The length of the coil. The upstream segment should be over about 60 feet long and less than about 70 feet. The downstream segment should be about 3 feet long. A second embodiment of the apparatus is shown in FIGS. 5 to 15 . This embodiment is preferably for use with beer, although it can be for use with other carbonated and non-carbonated beverages. With reference to FIGS. 5, 9 , 10 and 11 , a housing 110 is preferably composed of fiberglass, but may be of any appropriate material known to those skilled in the art. The housing 110 is mounted on a frame 160 which is preferably composed of steel or aluminum to provide structural support for the housing. The frame 160 is preferably equipped with wheels and a hitch to enable it to be towed behind a golf cart, all terrain vehicle, truck or any other such vehicle with suitable towing capabilities. The preferred embodiment of the housing 110 preferably defines 4 chambers, 120 , 140 , 150 and 180 but in another embodiment the housing may define as few as one chamber. Chamber 120 is watertight. The housing 110 defines an opening 121 which permits a mixture of preferably water and ice to be poured into the chamber 120 . A lid 122 seals chamber 120 . Other appropriate cooling liquids or fluids are also acceptable. A coil 170 , described in more detail below, is mounted to the bottom of the chamber 120 and is surrounded by the liquid and ice mixture. Agitators 171 and 172 are located in chamber 120 for agitating the water and ice. Preferably the agitators are submersible pumps. In alternate embodiments it is possible to locate the keg outside of the housing in a manner similar to that described with the first embodiment. The housing 110 defines openings 130 which run from the chamber 120 to the outer wall of the housing 110 . These openings 130 permit lengths of hoses 131 to run from the coil 170 to taps 132 . Hose 131 is preferably {fraction (3/16)}th inch in diameter and four to five feet in length. Hose 133 is preferably ⅜th inch in diameter and five to ten feet in length. The hoses 131 and 133 are preferably composed of braided polyvinyl chloride. The chamber 140 provides a hinged access door 143 which permits one or more beer kegs 141 to be placed inside. Hose 133 connects the coil 170 to the keg 141 . Mounting brackets plus adjustable straps (not illustrated) are provided to secure keg 141 in place. A keg coupler 142 is threadably received into a port on the top of the keg 141 . The keg coupler 142 provides a blow out valve with a preset pressure limit of 60 p.s.i., significantly higher than the pressure limit of standard North American keg couplers. Hose 182 attaches to the keg coupler and is preferably composed of braided polyvinyl chloride. Chamber 180 provides a housing for the gas cylinder 181 or compressor in a secure manner. A hinged door is provided to enable easy access to remove and replace cylinder 181 . Hose 182 is also attached to a pressurizing means 181 housed in chamber 180 . The pressurizing means is preferably so called “beer gas” stored in a conventional pneumatic or gas cylinder 181 . Beer gas is usually composed of from about 65 to 75 percent nitrogen and the remainder carbon dioxide. Any gas can be used which does not affect the flavour of the beverage stored in the keg 141 , for example pure carbon dioxide or even compressed air. The gas is introduced into the interior of the keg 141 through hose 182 which extends from the cylinder 181 to the keg 141 . A nozzle and pressure gauge (not illustrated) both of conventional construction are provided in the gas line so that the pressure within the keg can be monitored and controlled. An alternate means to pressurize the interior of the keg 141 is through the use of a compressor instead of a pre-pressurized gas cylinder. Chamber 150 provides a housing for a portable power source 151 capable of operating the agitators 171 and 172 . The power source 151 is preferably a 12 volt battery but may be any form of portable power, such as a generator. The power source 151 is connected to the agitators 171 and 172 by way of wiring 152 . The wiring passes into chamber 120 and is waterproof. The opening through which the wire passes is sealed around the wire such that the liquid and ice mixture in chamber 120 does not seep out. Conduit 400 comprises hoses 131 and 133 and coil 170 and is shown in FIG. 6 . Other conduits that permit the flow of a fluid or liquid and which permit satisfactory heat exchange to cool the beverage flowing through the conduit are also acceptable. For example any form of metal or steel tubing that permits heat exchange is acceptable. Notable exceptions are copper and lead which can poison the beverage. Conduit 400 is preferably substantially 70 feet long. Slight variations of the length of the conduit are possible. Preferably the conduit is ⅜ inch for the first 5 feet. Preferably the inner diameter of the conduit is decreased to ¼ inch at the 5 foot point along the length of the conduit. The inner diameter is preferably ¼ inch from the 5 foot point to the 65 foot point along the length of the conduit and is described herein as coil 170 . Preferably the inner diameter of the conduit is decreased to {fraction (3/16)} inch at the 65 foot point along the length of the conduit. The inner diameter is preferably {fraction (3/16)} inch from the 65 foot point to the 70 foot point along the length of the conduit. The first 5 feet and the last 5 feet of the conduit are preferably composed of braided polyvinyl chloride and have been described herein as hoses 131 and 133 . In alternate embodiments the total length of the conduit can be in the range of 60 to 70 feet. If the conduit is shorter than 60 feet then the volume of beer at the desired temperature will diminish. If the conduit is longer than 70 feet, a higher pressure of beer gas is required to cause the beer to flow at a satisfactory rate. As shown in FIG. 6, two or more conduits 170 can be wound into a coil thereby permitting more than one beer line to be cooled simultaneously. Preferably, conduit 400 is composed of stainless steel, although any appropriate material or combinations of materials may be used the selection of which will be apparent to one skilled in the art. Coil 170 is mounted inside a perforated vessel 300 with solid anterior and posterior side plates 190 . Perforated vessel 300 is shown in FIGS. 8, 14 and 15 and is described in greater detail below. The inner circumference of coil 170 wound as a coil is of sufficient size to permit the placement of agitators 171 and 172 therein. Agitators 171 and 172 are shown in FIGS. 7 and 12 - 15 and are described in greater detail below. The preferred pressure of beer gas in the container 141 is about 45 to 55 p.s.i. Most preferably, the pressure is 47 p.s.i. Hose 133 is preferably ⅜th inch in diameter and decreases to ¼ inch inner diameter at the point of connection 210 to the coil 170 , however the decrease may also be abrupt. The two segments may be interconnected by a joint of conventional constructions. Hose 133 is preferably of a length in the range of five to ten feet. The hose 133 is of a significantly lesser diameter than the container 141 . As such any beer which is forced into hose 133 is subject to greater pressures which begins to entrain gas which has separated from the beer. The hose 131 is connected to coil 170 at a connection 200 . The two segments may be interconnected by a joint of conventional constructions. The downstream end of hose 131 connects to a dispensing means 132 . Hose 131 is preferably ¼ inch in diameter and tapers to {fraction (3/16)}th inch diameter at dispensing means 132 , however the decrease may also be abrupt. Hose 131 is preferably of a length in the range of four to five feet. Significantly longer and the flow of beer will diminish to a trickle and significantly shorter and foaming becomes a problem. The hose 131 is of a lesser diameter than the coil 170 . As such any beer which is forced into hose 131 is subject to greater pressures than the beer was subject to in coil 170 . As such any remaining separated gas is reintroduced into the beer. While it is desirable that hose 131 be substantially entirely within the chamber 120 , the apparatus will still work if hose 131 is partly within and partly outside chamber 120 . It is preferable that only three sections of a reduced diameter hosing is required to fully defoam the beer, however, additional sections of hose of a reducing diameter can be added until the beer is defoamed to a desired extent. Alternatively, if the beer in the container 141 is not subject to significant agitation or foam inducing conditions, fewer sections of hose with a reducing diameter will be necessary to defoam the beer. The coil 170 is surrounded by a perforated vessel or cylinder 220 shown in FIGS. 8, 14 and 15 which is closed on the anterior and posterior sides with solid metal plates 190 . The cylinder 220 and the sides are preferably made of a resilient non-corrosive substance such as stainless steel or plastic, however, any appropriate substance can be used and will be known to a person skilled in the art. The vessel 300 has openings sufficient to permit the connecting ends of the coil 210 and 200 to protrude there from. The vessel 300 is preferably mounted on the bottom and in the center of chamber 120 , but may be mounted anywhere within said chamber. The perforations 230 are preferably ⅛th inch in diameter and evenly spaced ⅛th inch apart across the entire surface of the perforated vessel 220 . The perforations filter ice particles from the liquid and ice mixture in order that the agitators 171 and 172 are not damaged from drawing large ice particles into the their intake ports 175 . The preferred sizing and spacing of the perforations permits a sufficient volume of liquid to be drawn through the perforated vessel 220 by way of the agitators. However, any configuration of perforation size and spacing may be used so long as the agitators are not being damaged and can draw sufficient liquid to provide adequate cooling of the beer in the coil 170 . If the agitators have adequate filters on their intake ports 175 , the perforated vessel 220 may not be necessary at all. Agitators 171 and 172 are shown in FIG. 7 and 12 - 15 . Preferably, the agitators are submersible pumps. Most preferably, the pumps are capable of processing 500 gallons of water per hour. However, submersible pumps that process more or less water per minute, or even only one submersible pump may be used provided they or it are capable of sufficiently agitating the liquid and ice mixture to cool the beer in the coil 170 and there is a sufficient power supply to operate them or it. Alternatively, the agitators may not need to be submersible pumps (not illustrated) and may be pumps located externally to chamber 120 . Such externally located pumps would be connected to chamber 120 by way of hoses which port into chamber 120 . Such externally located pumps could agitate the water and ice mixture by way of drawing in said mixture through an intake port hose and expelling it through an outtake port hose. Preferably, agitators 171 and 172 are mounted on the anterior and posterior side plates 190 of the perforated vessel 300 . The mounting of the pumps in such a manner places them inside the inner circumference of coil 170 . Preferably, agitators 171 and 172 are oriented in such a manner that their respective discharge nozzles 173 and 174 are horizontally and laterally diagonally spaced along the longitudinal axis of the coil 170 and directed toward the centre thereof Agitator 171 is located on the same side of the coil 170 as the connection point 210 . Agitator 172 is located on the same side of the coil 170 as the connection point 200 . The preferred position of the agitators imparts a vorticular flow to the liquid and ice mixture which provides for maximum cooling of the beer in the coil 170 , while also minimizing the draw on the portable power supply 151 to operate the agitators. Alternatively, the agitators may be only laterally or horizontally spaced along the longitudinal axis of the coil 170 with their respective discharge nozzles 173 and 174 pointing toward the centre thereof. In addition, the discharge nozzles 173 and 174 may be directed in any direction suitable for sufficiently agitating the liquid and ice mixture to adequately cool the beer. The intake ports 175 on the agitators are positioned to abut the walls of the coil 170 . The intake ports 175 draw liquid through the perforated vessel 300 and over the exterior of coil 170 . The perforated vessel 300 prevents large ice particles from the liquid and ice mixture from being drawn into the agitators 171 and 172 . An agitator suitable for causing the liquid and ice mixture to agitate is submersible pump model V500 no. 4204 sold by Attwood Company. The agitators 171 and 172 are powered by a 12 volt battery and draws 1.5 amperes current. The portable power supply 151 may be a battery of sufficient voltage or any other appropriate power source known to those skilled in the art. The portable power supply 151 is located in chamber 150 . Wiring 151 is connected to the power supply 151 , is routed through chamber 120 and is connected to agitators 171 and 172 . Wiring 151 is shielded against contact with the liquid and ice mixture. The keg 141 contains beer at an ambient temperature. The keg 141 is pressurized by way of a gas cylinder 181 or compressor which forces compressed gas through hose 182 , into the keg coupler 142 which is threadably received into keg 141 . The pressure must be sufficient to force the beverage into and through the entire length of coil 170 and hoses 133 and 131 . It is preferable to use pressure in the range of 45 to 55 p.s.i., in particular 47 p.s.i. is ideal. The beer flows from keg 141 , through the keg coupler 142 to a hose 133 . The beer flows from the hose 133 to the coil 170 . From the coil 170 , the beer flows through a second hose 131 to the tap 132 from which the beer may be selectively discharged. Any gases which have escaped from the beer while it is stored in the keg 141 are entrained into the beer by way of forcing the beer under pressure through hose 133 , coil 170 and hose 131 . At each step the diameter of hose or conduit through which the beer is forced is reduced. The coil 170 is cooled by the liquid and ice mixture as it is agitated around the coil. Rapid and thorough heat exchange along the entire length of the coil 170 is achieved by the continuous and uninterrupted flow of the chilled liquid portion of said mixture over the coil. The positioning of the agitators is such the agitators discharges the chilled liquid of said mixture onto the side plates 190 . The liquid impacts the side plates 190 with sufficient power to be deflected over the exterior of coil 170 and out through the perforations 230 . The liquid exits the perforations and with sufficient power to impart a vorticular flow pattern with its nexus located at the centre of the longitudinal axis of the coil 170 . The vorticular flow pattern circulates the chilled liquid of said mixture such that there is maximum uniform surface exposure to the coil 170 thereby ensuring that the entire coil is evenly cooled. As well, the vorticular flow pattern ensures the entire liquid of said mixture is utilized to cool the coil 170 , not just that portion of chilled liquid in direct proximity with the coil. The beer is preferably cooled to a temperature in the range of 32 to 34 degrees Fahrenheit. As it passes through the coil the cooling of the beer further reduces any foaming and permits more of the separated gases to be reintroduced into the beer. Non-foamed beverage is continuously delivered from the conduit to the exterior of the housing by way of a dispensing tap. The combined effect of cooling the conduit by the circulation over the coil of the cooling fluid and the delivery of the beverage through diminishing diameters of the conduit to augment the pressure allowed for the continuous delivery of non-foamed beverage even under hot conditions and where the beverage has been agitated. Most preferably, the taps are spring loaded to prevent them from jarring open over rough terrain. It should be noted that the cooler of the subject invention may be used to cool any carbonated beverage and may be stationary as well as mobile. The drawings and description are intended to be illustrative of one way in which the subject invention may be put into practice. They are not intended however to limit the scope of the invention.
An apparatus is provided for cooling a carbonated beverage stored in a container and dispensing non-foamed carbonated beverage. A method of cooling and delivering non-foamed beverage with the apparatus is also provided. The beverage is preferably beer. The apparatus comprises a housing that has a number of chambers. A chamber can optionally be provided for receiving a number of beer kegs. A pressurizing device is attached to a beer keg for maintaining the beer under pressure in the keg. A conduit is received in one of the chambers and communicates between the beer keg and a tap located on the exterior of the apparatus. A water and ice cooling mixture is circulated over the conduit in the same chamber for cooling the conduit. A perforated vessel surrounds the conduit to protect the conduit and the agitators from being damaged by ice particles. At least two agitators for circulating the cooling fluid over the conduit are located in chamber where the conduit is received. The agitators are positioned to continuously circulate cold water over the conduit for maximum heat exchange.
Briefly describe the main idea outlined in the provided context.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. application Ser.", "No. 09/764,441, filed Jan. 19, 2001, which claims priority to Canadian Application No. 2296579, filed Jan. 20, 2000.", "FIELD OF THE INVENTION The present invention relates to apparatuses and processes for cooling beverages and more particularly to a portable coolers having provision for reducing or eliminating the formation of foam in carbonated beverages.", "BACKGROUND OF THE INVENTION There are numerous events and activities where one desires to enjoy cool beverages.", "However, many such events and activities are located in places where there is no access to cool beverages chilled by traditionally means such as refrigerators.", "In particular, remote locations such as on the golf courses, sporting events, outdoor concerts and other outdoor activities, do not facilitate the easy distribution of cool beverages.", "Easy distribution of cool beverages is also desirable at resorts, bars and restaurants.", "Most consumers at these activities desire cool beverages.", "Numerous means have been developed to provide such beverages.", "There exists in the prior art inventions which have a similar purpose as the subject invention.", "In particular U.S. Pat. No. 4,225,059 describes a portable beverage cooler and dispenser.", "The apparatus includes an air cylinder for pressurizing beer kegs.", "The beer kegs are located in a housing.", "The beer kegs are connected to a coiled dispensing hose also located in the housing.", "The hose passes through ice located in ice chambers.", "This serves to cool the beer before it is dispensed through spigots at the top of the apparatus.", "In addition, U.S. Pat. No. 2,223,152 describes a stationary beer cooling device.", "The device is not pressurized.", "The device cools the beer by circulating it through a cooling coil which is immersed in an ice water bath.", "The cooling coil is protected by a perforated metal sleeve so as to permit an operator to agitate the ice bath with a stick or a rod.", "The drawback to both of these inventions is that they do not adequately cool and de-foam beer.", "The most typical manner to provide cool beverages at remote locations is to transport canned beverages in coolers containing ice and distribute the canned beverages at the remote location.", "However, the use of canned beverages is more costly to the consumer and creates significant waste in the form of emptied cans.", "Further, the use of individual cans reduces the volume of beverage one is able to transport to such remote locations since the can packaging occupies the limited cooler space.", "To address the problems associated with canned beverages there have been attempts to use kegs or other such large vessels to distribute cool beverages at remote locations.", "However, this method also has drawbacks.", "It is difficult to cool large vessels so that the beverages are of an acceptable temperature.", "Further, portable containers are often subject to severe agitation when they are traveling over hilly or rough terrain such as golf courses.", "A combination of elevated temperature and agitation causes the beverages to form foam.", "If the beverage is beer, the beer which discharges from the container will be in the form of foam.", "This ruins the taste of the beverage and makes it impossible to pour the beer properly due to excess foaming.", "Since most beverages enjoyed by consumers are carbonated, minimizing foaming is of critical importance.", "When gas that is dissolved in a carbonated beverage leaves the liquid, it creates foam.", "The foam is often waste and is poured off before the beverage is served.", "If a carbonated beverage is not handled properly, 50% can be lost to foam waste.", "Further, even that portion of the carbonated beverage that does not foam will likely be of poor quality since the loss of carbonation will make the beverage less acidic or “flat.”", "Because the solubility of a gas in a liquid is higher at lower temperatures, the carbon dioxide gas is less likely to come out of solution and form foam at cooler temperatures.", "Accordingly, it is desirable to dispense carbonated beverages at cool temperatures.", "Another means to minimize foaming is to maintain the carbonated beverage under a certain amount of pressure.", "This is true because the solubility of a gas in a liquid is higher at elevated pressures.", "When the pressure on a carbonated beverage is released or reduced the gas dissolved therein leaves solution more readily and creates foam.", "Pressure can be maintained on carbonated beverages up to the point of dispensing it by forcing the beverage through a length of conduit of a lesser diameter than the conduit from which it was dispensed from the holding vessel.", "A significant portion of foam which is present at the time the carbonated beverage is dispensed from the vessel will be reabsorbed by the carbonated beverage by the time it is dispensed for the consumer.", "However, neither the cooling or pressurization of the carbonated beverage alone is sufficient to satisfactorily reduce foam.", "The prior art does not describe an apparatus or process, of a portable nature, which provides for the dispensing of cooled, non-foamed carbonated beverages in an economical manner.", "Therefore there is a need for such apparatuses and processes.", "SUMMARY OF THE INVENTION The present invention relates to an apparatus for cooling a carbonated beverage from a keg and for continuously delivering non-foamed carbonated beverage.", "The apparatus includes a conduit that is attachable to the keg and which has a varying diameter.", "The conduit is submerged in a cooling fluid that is agitated by agitators to flow over the conduit for heat exchange.", "The agitators are positioned to provide an advantageous flow pattern over the conduit.", "According to one aspect of the present invention there is provided an apparatus for cooling a carbonated beverage stored in a container and dispensing non-foamed carbonated beverage, the apparatus comprising: a housing defining a chamber having first and second openings;", "means attached to the container for maintaining the beverage under pressure in said container;", "a conduit located in the chamber, the conduit communicating with the container through said first opening, the conduit further communicating with the second opening for delivering said beverage from the chamber;", "cooling fluid located in said chamber for cooling the conduit;", "and at least two agitators for circulating the cooling fluid over the conduit, the at least two agitators being mounted in the chamber at opposing ends of the chamber and being laterally spaced.", "According to another aspect of the present invention there is provided an apparatus for cooling a carbonated beverage stored in a container and dispensing non-foamed carbonated beverage, the apparatus comprising: a housing defining a chamber having first and second openings;", "pressurizing means attached to the container for maintaining the beverage under pressure in said container;", "a conduit located in the chamber, the conduit communicating with the container through said first opening, the conduit further communicating with the second opening for delivering said beverage from the chamber;", "a perforated vessel mounted in the chamber, said perforated vessel surrounding the conduit;", "cooling fluid located in said chamber for cooling the conduit, the cooling fluid including solid fragments, said fragments being substantially larger than the perforations in said vessel;", "an agitator for circulating the cooling fluid over the conduit;", "and a pressure valve located between the conduit and the container for detecting a predetermined pressure rating in said container.", "According to another aspect of the present invention there is provided an apparatus for cooling a carbonated beverage stored in a container and dispensing non-foamed carbonated beverage, the apparatus comprising: a housing defining a chamber having first and second openings;", "means attached to the container for maintaining the beverage under pressure in said container;", "a conduit located in the chamber, the conduit communicating with the container through said first opening, the conduit further communicating with the second opening for delivering said beverage from the chamber, the conduit having a length of substantially at least 70 feet and having regions of decreased inner diameter at regions at substantially 5 feet and at substantially 65 feet along said length;", "cooling fluid located in said chamber for cooling the conduit;", "and an agitator for circulating the cooling fluid over the conduit.", "According to yet another aspect of the present invention there is provided a method of cooling a carbonated beverage and continuously delivering non-foamed a carbonated beverage, the method comprising the following steps: providing a conduit having regions of decreased inner diameter for delivering the beverage from the container;", "pressurizing the beverage in the container to induce flow of the beverage into the conduit;", "providing a cooling fluid;", "agitating the cooling fluid to continuously flow over the conduit;", "and delivering the beverage through the regions of decreased inner diameter to entrain carbon dioxide gas into the beverage.", "DESCRIPTION OF THE DRAWINGS The invention is described with reference to the accompanying drawings in which: FIG. 1 is a perspective view of a first embodiment of the present invention mounted on a trailer;", "FIG. 2 is a perspective view, partly cut away, of a cooling coil of the first embodiment;", "FIG. 3 is a side view, cut away and enlarged scale, of a portion of the cooling coil of the first embodiment;", "FIG. 4 is a cross-section of the coil of the first embodiment.", "FIG. 5 is an exploded view of the housing of the second embodiment;", "FIG. 6 is a perspective view of the coil of the second embodiment;", "FIG. 7 is a perspective view with portions cut away of the agitators of the second embodiment;", "FIG. 8 is a perspective view with portions cut away of the perforated vessel surrounding the cooling coil of the second embodiment;", "FIG. 9 is a perspective view of the housing of the second embodiment;", "FIG. 10 is a perspective view of the housing of the second embodiment;", "FIG. 11 is a plan view of the housing of the second embodiment;", "FIG. 12 is a perspective view with portions cut away of the coil and an agitator of the second embodiment;", "FIG. 13 is a cross section of the coil and the perforated vessel of the second embodiment;", "FIG. 14 is a detailed view of the coil assembly of the second embodiment;", "and FIG. 15 is an exploded view of the coil assembly of the second embodiment.", "Like reference characters refer to like parts throughout the description of the drawings.", "DESCRIPTION OF PREFERRED EMBODIMENTS The description which follows is of an apparatus for cooling and dispensing beer but it is to be understood that the apparatus of the invention is not limited to one for cooling and dispensing beer.", "The apparatus can be used to cool and dispense other carbonated beverages such as non-alcoholic and alcoholic drinks.", "The apparatus can for example be used to dispense carbonated soft drinks and spritzers.", "FIGS. 1-4 show a first embodiment of the present invention.", "With reference to FIG. 1, a trailer 10 holds a keg 14 , a cooler 16 and a tap 18 from which beverage within the keg and cooler discharge.", "The keg 14 contains beer which flows through a hose 20 to the cooler where it is chilled.", "From the cooler, the beer flows through a second hose 22 to the tap 18 from which it discharges.", "Preferably hoses 20 and 22 are composed of braided polyvinyl chloride.", "The trailer 10 is mounted on wheels 24 so that it can be towed by a motorized golf cart 26 .", "The keg 14 can be removed from the trailer when it is empty and replaced by another full keg.", "Beer within the keg 14 is maintained under pressure by means of so called “beer gas”", "stored in a conventional pneumatic or gas cylinder 30 .", "Beer gas is usually composed of from about 65 to 75 percent nitrogen and the remainder carbon dioxide.", "The gas is introduced into the interior of the keg 14 through a hose 32 which extends from the cylinder to the keg.", "A nozzle and pressure gauge (not illustrated) both of conventional construction are provided in the gas line so that the pressure within the keg can be monitored and controlled.", "A compressor can also be used.", "With reference to FIG. 2, a conduit or coil 40 extends through the cooler 16 .", "The coil has a point of entry 40 a at which beer enters the coil.", "From the point of entry, the beer enters an upstream segment 40 b and from the upstream segment, the beer flows to a downstream segment 40 c. The inner diameter of the coil decreases downstream of the flow of beer.", "In FIG. 3 the inner wall of the coil diminishes gradually but the decrease may be abrupt.", "In the latter event, the inner diameter of the upstream segment is greater than that of the downstream segment.", "The two segments may be interconnected by a joint of conventional construction.", "Preferably, the two segments of the coil are composed of stainless steel and each has a constant inner diameter.", "The inner diameter of the coil at the point of entry 40 a is about ⅜ inch as is that of hose 20 through which the beer flows to the cooler from the keg.", "The upstream segment 40 b has an inner diameter of about ¼ inch while the downstream segment has an inner diameter of {fraction (3/16)} inch.", "The upstream segment should be about 60 to about 70 feet in length measured along the longitudinal axis of the coil.", "Any shorter than 60 feet and the volume of beer at the desired temperature will diminish while any longer than 70 feet, while permissible, will necessitate a higher pressure of beer gas to cause the beer to flow at a satisfactory rate.", "The preferred pressure of beer gas is about 45 to 55 p.s.i. The pressure of beer gas is most preferably 47 p.s.i. The downstream segment should be about 3 feet in length measured along the longitudinal axis of the coil.", "Significantly longer and the flow of beer will diminish to a trickle and significantly shorter and foaming becomes a problem.", "The downstream segment terminates at the tap and accordingly it will straighten at 40 d at its downstream end.", "While it is desirable that the downstream segment be substantially entirely within the cooler, the apparatus will still work if the downstream segment is partly within and partly outside the cooler.", "With reference to FIGS. 2 and 4, the coil is mounted within a perforated vessel or cylinder 50 which is closed at both ends 52 , 54 .", "The cylinder is mounted within cooler 16 which has solid sides and end walls.", "The cooler contains water and particles of ice 56 which serve to cool the beer within the coil.", "A drain (not illustrated) is provided at the bottom of the cooler through which the water can be drawn off.", "A faucet (not illustrated) is provided in the discharge line for controlling the flow from the drain.", "An opening (not illustrated) is formed on the top of cooler for admission of fresh water and ice particles.", "The opening is closed by a lid (not illustrated) for preventing the contents of the vessel from spilling out when the trailer is moving.", "Two submersible pumps 60 , 62 are mounted within the vessel to cause the water to circulate.", "The water circulates freely around the pumps but the ice particles are prevented from contacting and damaging the pump because they are too large to penetrate through the perforations 64 in cylinder 50 .", "A pump suitable for causing the water and ice particles to circulate is submersible pump model V500 no. 4204 sold by Attwood Company.", "The pump is powered by a 12 volt battery.", "The battery is mounted on the trailer so that the trailer is completely portable and self-contained.", "With reference to FIG. 1, cooled beer flows from the coil to tap 18 .", "The tap is of conventional construction and is spring-loaded closed.", "Such a tap ensures that pressure within the line through which beer flows is maintained at the desired value at all times except when the tap is opened to dispense beer.", "The beer cooler described above is capable of cooling beer from ambient temperature to a temperature in the range of about 32 to 34 degrees F. This is the range generally favoured by most consumers of beer brewed in North America.", "Thus the temperature of the beer in the keg will be ambient while the temperature at tap 18 will be about 32 to about 34 degrees.", "The conditions which have an effect on the amount of foam which discharges from the tap are as follows: 1.", "The pressure of gas within the keg.", "The pressure should be maintained at about 45 to 55 p.s.i, preferably 47 p.s.i. The gauge which measures the pressure within the keg should be monitored to ensure that the pressure remains within this range.", "It is believed that if the pressure is below this range, carbon dioxide in the beer comes out of solution and combines with beer as foam.", "If the pressure is above this range, the keg must be constructed of heavier and stronger material at added cost and with no significant benefit.", "The inner diameter of the coil.", "The diameter must decrease as the beer flows downstream.", "As indicated above the inner diameter of the coil at the point of entry into the perforated cylinder 50 should preferably be about ¼ inch and at the point of exit from the cylinder about {fraction (3/16)} inch.", "The length of the coil.", "The upstream segment should be over about 60 feet long and less than about 70 feet.", "The downstream segment should be about 3 feet long.", "A second embodiment of the apparatus is shown in FIGS. 5 to 15 .", "This embodiment is preferably for use with beer, although it can be for use with other carbonated and non-carbonated beverages.", "With reference to FIGS. 5, 9 , 10 and 11 , a housing 110 is preferably composed of fiberglass, but may be of any appropriate material known to those skilled in the art.", "The housing 110 is mounted on a frame 160 which is preferably composed of steel or aluminum to provide structural support for the housing.", "The frame 160 is preferably equipped with wheels and a hitch to enable it to be towed behind a golf cart, all terrain vehicle, truck or any other such vehicle with suitable towing capabilities.", "The preferred embodiment of the housing 110 preferably defines 4 chambers, 120 , 140 , 150 and 180 but in another embodiment the housing may define as few as one chamber.", "Chamber 120 is watertight.", "The housing 110 defines an opening 121 which permits a mixture of preferably water and ice to be poured into the chamber 120 .", "A lid 122 seals chamber 120 .", "Other appropriate cooling liquids or fluids are also acceptable.", "A coil 170 , described in more detail below, is mounted to the bottom of the chamber 120 and is surrounded by the liquid and ice mixture.", "Agitators 171 and 172 are located in chamber 120 for agitating the water and ice.", "Preferably the agitators are submersible pumps.", "In alternate embodiments it is possible to locate the keg outside of the housing in a manner similar to that described with the first embodiment.", "The housing 110 defines openings 130 which run from the chamber 120 to the outer wall of the housing 110 .", "These openings 130 permit lengths of hoses 131 to run from the coil 170 to taps 132 .", "Hose 131 is preferably {fraction (3/16)}th inch in diameter and four to five feet in length.", "Hose 133 is preferably ⅜th inch in diameter and five to ten feet in length.", "The hoses 131 and 133 are preferably composed of braided polyvinyl chloride.", "The chamber 140 provides a hinged access door 143 which permits one or more beer kegs 141 to be placed inside.", "Hose 133 connects the coil 170 to the keg 141 .", "Mounting brackets plus adjustable straps (not illustrated) are provided to secure keg 141 in place.", "A keg coupler 142 is threadably received into a port on the top of the keg 141 .", "The keg coupler 142 provides a blow out valve with a preset pressure limit of 60 p.s.i., significantly higher than the pressure limit of standard North American keg couplers.", "Hose 182 attaches to the keg coupler and is preferably composed of braided polyvinyl chloride.", "Chamber 180 provides a housing for the gas cylinder 181 or compressor in a secure manner.", "A hinged door is provided to enable easy access to remove and replace cylinder 181 .", "Hose 182 is also attached to a pressurizing means 181 housed in chamber 180 .", "The pressurizing means is preferably so called “beer gas”", "stored in a conventional pneumatic or gas cylinder 181 .", "Beer gas is usually composed of from about 65 to 75 percent nitrogen and the remainder carbon dioxide.", "Any gas can be used which does not affect the flavour of the beverage stored in the keg 141 , for example pure carbon dioxide or even compressed air.", "The gas is introduced into the interior of the keg 141 through hose 182 which extends from the cylinder 181 to the keg 141 .", "A nozzle and pressure gauge (not illustrated) both of conventional construction are provided in the gas line so that the pressure within the keg can be monitored and controlled.", "An alternate means to pressurize the interior of the keg 141 is through the use of a compressor instead of a pre-pressurized gas cylinder.", "Chamber 150 provides a housing for a portable power source 151 capable of operating the agitators 171 and 172 .", "The power source 151 is preferably a 12 volt battery but may be any form of portable power, such as a generator.", "The power source 151 is connected to the agitators 171 and 172 by way of wiring 152 .", "The wiring passes into chamber 120 and is waterproof.", "The opening through which the wire passes is sealed around the wire such that the liquid and ice mixture in chamber 120 does not seep out.", "Conduit 400 comprises hoses 131 and 133 and coil 170 and is shown in FIG. 6 .", "Other conduits that permit the flow of a fluid or liquid and which permit satisfactory heat exchange to cool the beverage flowing through the conduit are also acceptable.", "For example any form of metal or steel tubing that permits heat exchange is acceptable.", "Notable exceptions are copper and lead which can poison the beverage.", "Conduit 400 is preferably substantially 70 feet long.", "Slight variations of the length of the conduit are possible.", "Preferably the conduit is ⅜ inch for the first 5 feet.", "Preferably the inner diameter of the conduit is decreased to ¼ inch at the 5 foot point along the length of the conduit.", "The inner diameter is preferably ¼ inch from the 5 foot point to the 65 foot point along the length of the conduit and is described herein as coil 170 .", "Preferably the inner diameter of the conduit is decreased to {fraction (3/16)} inch at the 65 foot point along the length of the conduit.", "The inner diameter is preferably {fraction (3/16)} inch from the 65 foot point to the 70 foot point along the length of the conduit.", "The first 5 feet and the last 5 feet of the conduit are preferably composed of braided polyvinyl chloride and have been described herein as hoses 131 and 133 .", "In alternate embodiments the total length of the conduit can be in the range of 60 to 70 feet.", "If the conduit is shorter than 60 feet then the volume of beer at the desired temperature will diminish.", "If the conduit is longer than 70 feet, a higher pressure of beer gas is required to cause the beer to flow at a satisfactory rate.", "As shown in FIG. 6, two or more conduits 170 can be wound into a coil thereby permitting more than one beer line to be cooled simultaneously.", "Preferably, conduit 400 is composed of stainless steel, although any appropriate material or combinations of materials may be used the selection of which will be apparent to one skilled in the art.", "Coil 170 is mounted inside a perforated vessel 300 with solid anterior and posterior side plates 190 .", "Perforated vessel 300 is shown in FIGS. 8, 14 and 15 and is described in greater detail below.", "The inner circumference of coil 170 wound as a coil is of sufficient size to permit the placement of agitators 171 and 172 therein.", "Agitators 171 and 172 are shown in FIGS. 7 and 12 - 15 and are described in greater detail below.", "The preferred pressure of beer gas in the container 141 is about 45 to 55 p.s.i. Most preferably, the pressure is 47 p.s.i. Hose 133 is preferably ⅜th inch in diameter and decreases to ¼ inch inner diameter at the point of connection 210 to the coil 170 , however the decrease may also be abrupt.", "The two segments may be interconnected by a joint of conventional constructions.", "Hose 133 is preferably of a length in the range of five to ten feet.", "The hose 133 is of a significantly lesser diameter than the container 141 .", "As such any beer which is forced into hose 133 is subject to greater pressures which begins to entrain gas which has separated from the beer.", "The hose 131 is connected to coil 170 at a connection 200 .", "The two segments may be interconnected by a joint of conventional constructions.", "The downstream end of hose 131 connects to a dispensing means 132 .", "Hose 131 is preferably ¼ inch in diameter and tapers to {fraction (3/16)}th inch diameter at dispensing means 132 , however the decrease may also be abrupt.", "Hose 131 is preferably of a length in the range of four to five feet.", "Significantly longer and the flow of beer will diminish to a trickle and significantly shorter and foaming becomes a problem.", "The hose 131 is of a lesser diameter than the coil 170 .", "As such any beer which is forced into hose 131 is subject to greater pressures than the beer was subject to in coil 170 .", "As such any remaining separated gas is reintroduced into the beer.", "While it is desirable that hose 131 be substantially entirely within the chamber 120 , the apparatus will still work if hose 131 is partly within and partly outside chamber 120 .", "It is preferable that only three sections of a reduced diameter hosing is required to fully defoam the beer, however, additional sections of hose of a reducing diameter can be added until the beer is defoamed to a desired extent.", "Alternatively, if the beer in the container 141 is not subject to significant agitation or foam inducing conditions, fewer sections of hose with a reducing diameter will be necessary to defoam the beer.", "The coil 170 is surrounded by a perforated vessel or cylinder 220 shown in FIGS. 8, 14 and 15 which is closed on the anterior and posterior sides with solid metal plates 190 .", "The cylinder 220 and the sides are preferably made of a resilient non-corrosive substance such as stainless steel or plastic, however, any appropriate substance can be used and will be known to a person skilled in the art.", "The vessel 300 has openings sufficient to permit the connecting ends of the coil 210 and 200 to protrude there from.", "The vessel 300 is preferably mounted on the bottom and in the center of chamber 120 , but may be mounted anywhere within said chamber.", "The perforations 230 are preferably ⅛th inch in diameter and evenly spaced ⅛th inch apart across the entire surface of the perforated vessel 220 .", "The perforations filter ice particles from the liquid and ice mixture in order that the agitators 171 and 172 are not damaged from drawing large ice particles into the their intake ports 175 .", "The preferred sizing and spacing of the perforations permits a sufficient volume of liquid to be drawn through the perforated vessel 220 by way of the agitators.", "However, any configuration of perforation size and spacing may be used so long as the agitators are not being damaged and can draw sufficient liquid to provide adequate cooling of the beer in the coil 170 .", "If the agitators have adequate filters on their intake ports 175 , the perforated vessel 220 may not be necessary at all.", "Agitators 171 and 172 are shown in FIG. 7 and 12 - 15 .", "Preferably, the agitators are submersible pumps.", "Most preferably, the pumps are capable of processing 500 gallons of water per hour.", "However, submersible pumps that process more or less water per minute, or even only one submersible pump may be used provided they or it are capable of sufficiently agitating the liquid and ice mixture to cool the beer in the coil 170 and there is a sufficient power supply to operate them or it.", "Alternatively, the agitators may not need to be submersible pumps (not illustrated) and may be pumps located externally to chamber 120 .", "Such externally located pumps would be connected to chamber 120 by way of hoses which port into chamber 120 .", "Such externally located pumps could agitate the water and ice mixture by way of drawing in said mixture through an intake port hose and expelling it through an outtake port hose.", "Preferably, agitators 171 and 172 are mounted on the anterior and posterior side plates 190 of the perforated vessel 300 .", "The mounting of the pumps in such a manner places them inside the inner circumference of coil 170 .", "Preferably, agitators 171 and 172 are oriented in such a manner that their respective discharge nozzles 173 and 174 are horizontally and laterally diagonally spaced along the longitudinal axis of the coil 170 and directed toward the centre thereof Agitator 171 is located on the same side of the coil 170 as the connection point 210 .", "Agitator 172 is located on the same side of the coil 170 as the connection point 200 .", "The preferred position of the agitators imparts a vorticular flow to the liquid and ice mixture which provides for maximum cooling of the beer in the coil 170 , while also minimizing the draw on the portable power supply 151 to operate the agitators.", "Alternatively, the agitators may be only laterally or horizontally spaced along the longitudinal axis of the coil 170 with their respective discharge nozzles 173 and 174 pointing toward the centre thereof.", "In addition, the discharge nozzles 173 and 174 may be directed in any direction suitable for sufficiently agitating the liquid and ice mixture to adequately cool the beer.", "The intake ports 175 on the agitators are positioned to abut the walls of the coil 170 .", "The intake ports 175 draw liquid through the perforated vessel 300 and over the exterior of coil 170 .", "The perforated vessel 300 prevents large ice particles from the liquid and ice mixture from being drawn into the agitators 171 and 172 .", "An agitator suitable for causing the liquid and ice mixture to agitate is submersible pump model V500 no. 4204 sold by Attwood Company.", "The agitators 171 and 172 are powered by a 12 volt battery and draws 1.5 amperes current.", "The portable power supply 151 may be a battery of sufficient voltage or any other appropriate power source known to those skilled in the art.", "The portable power supply 151 is located in chamber 150 .", "Wiring 151 is connected to the power supply 151 , is routed through chamber 120 and is connected to agitators 171 and 172 .", "Wiring 151 is shielded against contact with the liquid and ice mixture.", "The keg 141 contains beer at an ambient temperature.", "The keg 141 is pressurized by way of a gas cylinder 181 or compressor which forces compressed gas through hose 182 , into the keg coupler 142 which is threadably received into keg 141 .", "The pressure must be sufficient to force the beverage into and through the entire length of coil 170 and hoses 133 and 131 .", "It is preferable to use pressure in the range of 45 to 55 p.s.i., in particular 47 p.s.i. is ideal.", "The beer flows from keg 141 , through the keg coupler 142 to a hose 133 .", "The beer flows from the hose 133 to the coil 170 .", "From the coil 170 , the beer flows through a second hose 131 to the tap 132 from which the beer may be selectively discharged.", "Any gases which have escaped from the beer while it is stored in the keg 141 are entrained into the beer by way of forcing the beer under pressure through hose 133 , coil 170 and hose 131 .", "At each step the diameter of hose or conduit through which the beer is forced is reduced.", "The coil 170 is cooled by the liquid and ice mixture as it is agitated around the coil.", "Rapid and thorough heat exchange along the entire length of the coil 170 is achieved by the continuous and uninterrupted flow of the chilled liquid portion of said mixture over the coil.", "The positioning of the agitators is such the agitators discharges the chilled liquid of said mixture onto the side plates 190 .", "The liquid impacts the side plates 190 with sufficient power to be deflected over the exterior of coil 170 and out through the perforations 230 .", "The liquid exits the perforations and with sufficient power to impart a vorticular flow pattern with its nexus located at the centre of the longitudinal axis of the coil 170 .", "The vorticular flow pattern circulates the chilled liquid of said mixture such that there is maximum uniform surface exposure to the coil 170 thereby ensuring that the entire coil is evenly cooled.", "As well, the vorticular flow pattern ensures the entire liquid of said mixture is utilized to cool the coil 170 , not just that portion of chilled liquid in direct proximity with the coil.", "The beer is preferably cooled to a temperature in the range of 32 to 34 degrees Fahrenheit.", "As it passes through the coil the cooling of the beer further reduces any foaming and permits more of the separated gases to be reintroduced into the beer.", "Non-foamed beverage is continuously delivered from the conduit to the exterior of the housing by way of a dispensing tap.", "The combined effect of cooling the conduit by the circulation over the coil of the cooling fluid and the delivery of the beverage through diminishing diameters of the conduit to augment the pressure allowed for the continuous delivery of non-foamed beverage even under hot conditions and where the beverage has been agitated.", "Most preferably, the taps are spring loaded to prevent them from jarring open over rough terrain.", "It should be noted that the cooler of the subject invention may be used to cool any carbonated beverage and may be stationary as well as mobile.", "The drawings and description are intended to be illustrative of one way in which the subject invention may be put into practice.", "They are not intended however to limit the scope of the invention." ]
REFERENCE TO A RELATED APPLICATION This application claims the benefit of our provisional patent application 60/376,845 filed May 2, 2002, which is relied on and incorporated herein by reference. The present invention relates to a process for the epoxidation of olefins, in particular to the working up of the product stream from the epoxidation reaction. PRIOR ART From EP-A 100 118 it is known that propene can be converted with hydrogen peroxide into propene oxide if titanium silicalite is used as catalyst. The reaction is preferably carried out in the presence of a water-miscible solvent in order to improve the solubility of propene in the reaction mixture. Preferably solvents are used that have a boiling point between the boiling points of propene oxide and water in order to be able to separate the solvent from the reaction mixture by a distillation stage and recycle it to the reaction. Methanol is preferably used as solvent. WO-A 99/07690 describes a process for the purification of a methanol-containing product stream from the epoxidation of propene that also contains acetaldehyde as an impurity. In this case the crude product stream from the epoxidation is subjected to a fractional distillation, in which connection it is particularly important that methanol is present in sufficient amount in the overhead product in order to achieve a substantially complete transfer of acetaldehyde to the bottom product. To this end the concentration of methanol in the overhead product is 2–6 wt. %. A distillation column with 20–60 separation stages and a reflux ratio of between 10:1 and 30:1 is furthermore necessary in order to achieve the best possible quantitative separation of the acetaldehyde. This arrangement accordingly involves high investment and operating costs for the distillation column. From U.S. Pat. No. 5,849,938 it is known that in the distillative working up of the methanol-containing reaction mixture from the propene epoxidation, the difference in volatilities of propene oxide and methanol can be increased by carrying out the distillation as an extractive distillation using water or propylene glycol as extraction agent. The purpose of this extractive distillation is to separate methanol as well as further high boiling point impurities like acetaldehyde as quantitatively as possible from the desired product, namely propene oxide, in one distillation step. The bottom stream from the distillation containing methanol, the polar extraction agent and impurities is preferably further worked-up by distillation to remove the polar extraction agent and the methanol fraction is preferably recycled to the epoxidation stage. EP-A 1 122 248 discloses a process for the working up of a product stream from the epoxidation of propene that contains propene, propene oxide, methanol and water, by separating this product stream into an overhead product containing propene, propene oxide and methanol, and into a bottom product containing methanol and water, wherein the separation takes place in a pre-evaporator with a maximum of 5 theoretical separation stages and 20 to 60% of the total amount of methanol entrained in the product stream is removed with the overhead product, the residue remaining in the bottom product. From the overhead product propene oxide is separated by extractive distillation using preferably water as extraction agent. The bottom stream from the extractive distillation comprising methanol and water can be directly recycled to the epoxidation stage. From the bottom stream of the pre-evaporation step methanol can be recovered by means of a fractionated distillation and recycled to the epoxidation stage. Although this process has considerable advantages in that the loss of propene oxide by secondary reactions in the working up is significantly reduced, it has now been discovered that in an continuous process whereby methanol recovered from the work-up of the reaction product is recycled to the epoxidation stage in a long term view the activity and selectivity of the catalyst in the epoxidation stage is reduced and a build up of impurities in the propene oxide product is observed. Therefore it is desired to have a process for the epoxidation of olefins wherein the above discussed disadvantages can be avoided. In WO 02/02545 the problem of build up of methyl formate in the product propene oxide is addressed. This build up can be reduced if methyl formate is removed from the methanol fraction by fractionated distillation prior to recycling the methanol fraction to the epoxidation stage. This reference is totally silent with respect to the problem of catalyst deactivation and it has been discovered that removing of methyl formate alone in a single distillation step as taught in WO 02/02545 would not solve the problem of long term deactivation of the catalyst system. Especially 1,1-Dimethoxyethan one of the impurities identified to cause catalyst deactivation has a boiling point almost identical with methanol and can therefore practically not be separated from methanol by means of distillation. Furthermore according to the teaching in WO 02/02545 an additional distillation step is necessary and a distillation column having 10 theoretical plates has to be used to achieve desired results contributing to increased investment and process costs. Therefore it is an object of the present invention to provide a process for the epoxidation of olefins resulting in a recovered solvent stream of increased purity. SUMMARY OF THE INVENTION This object has been attained by a process for the epoxidation of olefins by i) reacting an olefin with hydrogen peroxide in presence of an epoxidation catalyst and an alcoholic solvent; ii) separating product olefin oxide and unreacted olefin from the reaction product of step i); iii) recovering a stream comprising the alcoholic solvent, characterized by iv) subjecting the recovered stream of step iii) to hydrogenation. Preferably the recovered solvent stream comprises less than 2 wt. % olefin oxide and less than 1 wt. % unreacted olefin, more preferred less than 0.5 wt. % olefin oxide and less than 0.1 wt. % unreacted olefin and is most preferably substantially free of olefin oxide and unreacted olefin to minimize product losses in the hydrogenation step. According to a preferred embodiment of the present invention the process further comprises the steps of v) optionally purifying the solvent stream resulting from the hydrogenation step iv) and vi) reusing the solvent. Another preferred embodiment of the present invention refers to a process as defined above, wherein the product stream after separation of olefin oxide and unreacted olefin is subjected to hydrogenation and the alcoholic solvent is separated from the hydrogenated stream. During the investigations leading to the present invention the inventors discovered that not only methyl formate present in the solvent stream recycled to the epoxidation stage may have a detrimental effect on the reactivity of the catalyst system. Also other impurities like carbonyls, acetals and ketals, such as formaldehyde, acetaldehyde, dimethoxymethan and 1,1-dimethoxyethan lead to the deactivation of the catalyst. The inventors have surprisingly discovered that the level of impurities comprised in the solvent stream recovered from the epoxidation reaction can be substantially lowered by hydrogenation of the recovered solvent stream after the majority of the product olefin oxide and non-converted olefin has been removed from the solvent stream. When recycling the solvent after subjecting to hydrogenation to the epoxidation stage deactivation of the catalyst system can be considerably reduced. Furthermore it has been discovered, that compounds found as by-products and impurities and that are difficult to separate from the valuable products and additionally lead if the solvent is recycled to a deactivation of the catalyst system, are not only formed in the reaction step, but also in subsequent working-up stages. The formation of undesired by-products and impurities will especially occur in high temperature working-up stages like distillations when peroxide compounds are still present. Peroxides that may occur for example in the product of the epoxidation of propene are hydrogen peroxide and organic peroxides, like 1-hydroperoxy-2-propanol and 2-hydroperoxy-1-propanol that are formed in the reaction stage by the reaction of propene oxide with hydrogen peroxide. Thus an important advantage of the present invention is, that by hydrogenation not only impurities that are difficult to separate are converted into compounds that can be more easily separated but that also reactive intermediates that can result in subsequent reactions to impurities that are difficult to separate are removed. Thus the present invention is particularly advantageous if the solvent is at least partially recycled to the epoxidation step i), but is not restricted to such an embodiment. Alternatively the solvent recovered from the process of the present invention can also be reused in different manners well known by a person skilled in the art. DETAILED DESCRIPTION OF THE INVENTION The process according to the present invention is particularly suitable for the epoxidation of olefins having two to six carbon atoms, propene being particularly preferred. The epoxidation reaction of olefins according to the invention is described hereinafter with the example of propene as preferred olefin. The epoxidation reaction with hydrogen peroxide is carried out in the presence of a titanium silicalite catalyst in an alcoholic solvent. For the epoxidation of propene a solvent is preferably chosen whose boiling point is between the boiling points of propene oxide and water. Suitable solvents include, lower aliphatic alcohols, for example methanol, ethanol or tert.-butanol. Methanol is preferably used as solvent. Due to recycling of substances in the process, the solvent used may contain 0 to 20 wt. % of water. Hydrogen peroxide is used as an aqueous solution containing 10 to 70 wt. % of hydrogen peroxide. A hydrogen peroxide crude product obtained from the extraction step of the anthraquinone process and containing 30 to 45 wt. % of hydrogen peroxide is preferably used. Alternatively, hydrogen peroxide solutions in alcohols, preferably in methanol can be used. These alcoholic solutions can be prepared by reaction of hydrogen and oxygen in presence of a noble metal catalyst and the alcohol. Propene may be used mixed with propane in an amount of between 0 and 10 vol. % of propane. Crystalline, titanium-containing zeolites especially those of the composition (TiO 2 ) x (SiO 2 ) 1−x where x is from 0.001 to 0.05 and having a MFI or MEL crystalline structure, known as titanium silicalite-1 and titanium silicalite-2, are suitable as catalysts for the epoxidation process according to the invention. Such catalysts may be produced for example according to the process described in U.S. Pat. No. 4,410,501. The titanium silicalite catalyst may be employed as a shaped catalyst in the form of granules, extrudates or shaped bodies. For the forming process the catalyst may contain 1 to 99% of a binder or carrier material, all binders and carrier materials being suitable that do not react with hydrogen peroxide or with the epoxide under the reaction conditions employed for the epoxidation. Extrudates with a diameter of 1 to 5 mm are preferably used as fixed bed catalysts. In one embodiment of the invention the titanium silicalite catalyst is suspended in the reaction mixture during the reaction. The catalyst is then used in the form of a powder or in the form of a suspendable granular material that has been produced by forming in a manner known per se, for example by spray drying or fluidised bed granulation. When using a suspended catalyst, flow mixing reactors, for example stirred tank reactors or recycle reactors, as well as non-flow mixing reactors, for example tubular flow reactors, may be used for the reaction. A cascade consisting of one to three flow mixing reactors and a non-flow mixing reactor connected downstream is preferably used. In another embodiment of the invention the titanium silicalite catalyst is used as a fixed bed over which a mixture of the feedstock materials is passed. The catalyst is then used in the form of formed bodies that have been produced in a manner known per se, for example by extrusion with the addition of binders. When using a fixed bed catalyst, reactors with bubble column characteristics can be used, i.e. a continuous liquid phase and a dispersed gaseous phase simultaneously flow through the reactor. Alternatively the reaction can be run in a trickle bed modus. The epoxidation reaction is carried out at temperatures between 0 and 80° C., preferably between 40 and 65° C., and at elevated pressures of atmospheric pressure to 50 bar preferably 10 to 20 bar under an atmosphere substantially consisting of propene. The propene is used in excess and the residence time in the reactor is chosen so that a hydrogen peroxide conversion of more than 90%, preferably more than 95%, is achieved. The amount of solvent used is preferably chosen so as to achieve a ratio of 1 to 5 parts by weight of solvent to one part by weight of aqueous hydrogen peroxide solution. Before the working up stage the pressure of the reaction mixture is preferably released in a pressure release stage to the pressure employed in the working up of the propene oxide. Part of the propene dissolved in the reaction mixture and possibly propane is gassed out. The resultant gas is recompressed via a compressor to the pressure prevailing in the reactor and is returned to the reaction. The propene oxide still contained in the gas is preferably recovered by cooling and partial condensation after the compression. The work-up of the reaction product can be conducted in conventional way such as multiple distillation steps as well know in the art as long as at some stage of the entire working-up procedure at least one solvent stream is recovered. The at least one solvent stream or a combined stream resulting from different stages of the working-up procedure is subjected to a hydrogenation step according to the present invention. According to a preferred embodiment of the present process in step iv) the recovered solvent stream is subjected to a heterogeneous catalytic hydrogenation at a hydrogen partial pressure of 0.5 to 30 MPa. It is particularly preferred to conduct the hydrogenation step at a temperature in the range of 80° C. and 150° C., preferably 100° C. to 180° C. and at a hydrogen partial pressure of 1 to 25 MPa. Suitable catalysts are selected from supported catalysts comprising one or more of metals selected from the group consisting of Ru, Rh, Pd, Pt, Ag, Ir, Fe, Cu, Ni and Co. Alternatively Raney Nickel and Raney Cobalt both optionally being doped with one or more of the above mentioned can be used. The catalyst support is preferably selected from activated carbon and metal oxides selected from SiO 2 , TiO 2 , ZrO 2 and Al 2 O 3 , mixed oxides comprising at least two of Si, Al, Ti and Zr and mixtures thereof. In the epoxidation process of the present invention, carbonyl compounds are formed in the epoxidation reactor or during subsequent working-up stages, especially distillation stages. After separating the product propylene oxide, propene and other light boilers like methylformate from the reaction mixture, a stream comprising most of the solvent methanol, water, residual hydrogen peroxide and carbonyl compounds is obtained. In addition to the carbonyl compounds and the alcoholic solvent the corresponding acetals and ketals are also present. Therefore, according to a preferred embodiment of the present invention, a hydrogenation system including reactor, catalyst and reaction conditions is chosen to hydrogenate the carbonyl compounds as well as the corresponding acetals, like formals, hemiformals, ketals and hemiketals. These carbonyl compounds can be hydrogenated by using metal catalysts. These metals are preferably Nickel or precious metals. In case of precious metals, the metals are supported. The catalyst support can be any solid which is inert and does not deteriorate under the reaction conditions. Examples are silica, alumina, titania, zirconia, clays, calcium carbonate or mixed oxides like silica-alumina. Especially suitable catalysts for hydrogenating the carbonyl compounds, acetals and ketals are carbon with precipitated platinum, palladium, iridium or ruthenium. Preferred is ruthenium. The catalyst support can be in the form of spheres, pellets, tablets, granules, extrudates, balls etc. The precious metal loaded onto the support can be in the range of 0.01 to 50 wt. %. Preferred is the range of 0.1 to 5% based on the weight of the support. The precious metal catalyst can be prepared by any state of the art method. The metal can be distributed over the support surface by reducing the corresponding metal salts. These metal salts can be oxides, chlorides, nitrates, hydroxides, carbonates etc. These catalysts can be acquired commercially from producers like Degussa or Johnson Matthey (see Johnson Matthey The Catalyst Technical Handbook 2001, page 22 and 23). Furthermore, to ensure hydrogenation of carbonyl compounds and corresponding acetals and ketals, it is preferred to adjust the temperature in the hydrogenation step to be at least 80° C., more preferably in the range of from 100 to 150° C. and the hydrogen partial pressure to be at least 2 MPa, more preferably in the range of from 3 to 5 MPa. The hydrogenation reactor is preferably operated without additional cooling (adiabatic reactor). The hydrogenation can be carried out continuously or batch-wise e.g., in a suspension method or a fixed-bed method. It is especially preferred to use a trickle-bed reactor. Such reactors are well known. The fixed-bed catalysts to be used therein are preferably pellets with a diameter of 0.5 to 5 mm, especially 1 to 3 mm and with a length of 1 to 10 mm. The noble-metal content is in the customary range, preferably 0.5 to 5% by weight. By hydrogenation of a solvent stream resulting for example from the epoxidation of propene with hydrogen peroxide in a methanol solvent, wherein propene oxide and propene have been substantially removed, hydrogen peroxide is converted to water, 1-hydroperoxy-2-propanol, 2-hydroperoxy-1-propanol and hydroxyacetone are converted to 1,2-propanediol, formaldehyde is converted to methanol, acetaldehyde is converted to ethanol and 1,1-dimethoxyethane is converted to methanol and ethanol. Methylformate and dimethoxymethane will under the above specified conditions not be converted or only to a lesser extent. The alcoholic solvent stream resulting from the hydrogenation step can by either directly reused or if necessary for specific applications additionally purified for example by distillation prior to reusing the alcoholic solvent. After hydrogenation and prior to distillation it is preferred to adjust the pH of the alcoholic solvent stream to be below 7. This can be done by any acid that does not interfere with subsequent process steps like sulfuric acid. According to the most preferred embodiment the solvent stream purified according to the teaching of the present invention is recycled to the epoxidation stage i) of the present process. Most importantly, in a continuous process deactivation of the epoxidation catalyst can be at least considerably reduced by treating the solvent stream to be recycled in a hydrogenation step. Additionally the build up of low boiling impurities in the propene oxide product that are difficult to remove is substantially reduced resulting in an improved product quality. Additionally it has been surprisingly found that in a process wherein the solvent for example methanol is recycled to the reaction stage i) a build-up of methylformate and dimethoxymethane is not observed, although these compounds are not or only to a lesser extent converted in the hydrogenation reaction under the above specified conditions. Without wishing to be bound by theory it is believed that hydrogenation removes peroxides which otherwise would react in subsequent working-up stages forming methylformate, dimethoxymethane and precursors to these compounds. At the same time, hydrogenation also removes said and/or other precursors to methylformate and dimethoxymethane, like formaldehyde, and prevents them from being recycled to the reaction stage with the solvent. Consequently the present invention leads to a more effective and cost-efficient epoxidation process, since the operation cycle between regeneration cycles of the epoxidation catalyst can be considerably prolonged and to an improved product quality. These advantages can be achieved by a relatively simple measure of a hydrogenation step. Moreover the hydrogenation step can be easily integrated into the work-up procedure of the epoxidation product. According to one embodiment of the present invention the reaction mixture is separated in a pre-evaporator into an overhead product containing propene, possibly propane, propene oxide and solvent, and into a bottom product containing solvent, water, non-converted hydrogen peroxide higher boiling point by-products, such as for example propylene glycol, and if a suspension method is used for the epoxidation step suspended titanium silicalite catalyst. The pre-evaporator preferably has at most only 5 theoretical separation steps and is designed so that the stripping section corresponds to a simple evaporation and the remaining separation effect is achieved in the rectification section. The pre-evaporator is operated at a reflux ratio of at most 1.5 and if desired may also be operated totally without reflux. The pressure in the pre-evaporator is preferably chosen in the range from 1.5 to 8 bar in order to be able to condense the propene oxide with cooling water from the overhead product without having to use a cooling unit. The pre-evaporator is operated so that between 10 and 60% of the amount of solvent fed in with the reaction mixture is removed with the overhead product and the residue remains in the bottom product. In the operational procedure according to the invention more than 95%, typically more than 98% and preferably more than 99% of the propene oxide fed in is contained in the overhead product, and more than 90%, typically more than 97% and preferably more than 99% of the water fed in is contained in the bottom product. In this embodiment the bottom product from the pre-evaporator is subjected to the hydrogenation step of the present invention. The product stream fed to the pre-evaporator normally contains 0.5–20 wt. % of propene, 0–4 wt. % of propane, 5–35 wt. % of propene oxide, 35–80 wt. % of methanol, 5–40 wt. % of water, 0.1–8 wt. % of higher boiling point by-products, 0.1 to 5 wt. % hydrogen peroxide and 0–5 wt. % of titanium silicalite catalyst. This product stream is separated in the process according to the invention into an overhead product containing 1–40 wt. % of propene, 0–10 wt. % of propane, 15–75 wt. % of propene oxide, 20–85 wt. % of methanol and 0–5 wt. % of water, and into a bottom product containing 0–2 wt. % of propene oxide, 0–1 wt. % of propene, 30–80 wt. % of methanol, 15–65 wt. % of water, 0.1–10 wt. % of higher boiling point byproducts, 0.1–5 wt. % of hydrogen peroxide and 0–10 wt. % of titanium silicalite catalyst. The overhead product is preferably only partially condensed and the uncondensed propene, possibly mixed with propane, is recompressed via a compressor to the pressure prevailing in the reaction part and is recycled to the reaction, the propene oxide still contained in the gas preferably being removed by partial condensation after compression. The propene still dissolved in the condensate and possibly propane are stripped out from the condensate in a C3 stripper and the stripped-out gas is recycled to the partial condenser. The mixture of propene oxide and solvent contained in the C3 stripper is separated by distillation into a propene oxide crude product, which can be purified further in a manner known per se, and the solvent, which is recycled to the epoxidation reaction directly or can be combined with other solvent streams from different working-up stages and subjected to hydrogenation prior to recycling the solvent to the reaction stage. In a particularly preferred embodiment the mixture of propene oxide and solvent, preferably methanol, obtained from the C3 stripper is worked up further by extractive distillation to achieve as quantitative a separation as possible of the solvent. In this connection the mixture of propene oxide and methanol is added to the middle section of an extractive distillation column, preferably at a point corresponding to ⅓ of the total number of theoretical trays counting from the bottom, and a polar solvent with hydroxyl functionality and having a boiling point higher than that of methanol is added to the extractive distillation column at a point above the point at which the condensate enters, preferably at a point corresponding to ⅔ of the total number of theoretical trays counting from the bottom. The propene oxide crude product is distilled off at the head of the column and a mixture of methanol and the polar solvent is extracted as bottom product. The polar solvent is selected from water, glycols, glycol ethers and mixtures thereof. The preferred polar solvent is water since in this case the mixture of water and methanol can be either recycled directly to the reaction step without further purification or preferably is combined with other solvent streams and is hydrogenated prior to recycling. In order to achieve as complete a separation of the methanol as possible, a column with 25–100 theoretical separation steps and with a reflux ratio of 1–4 is already sufficient on account of the concentration of the propene oxide in the overhead product, the mathematical product of the number of separation steps and the reflux ratio typically being 75 to 125. On account of the pre-evaporation only a very small reflux ratio for the extractive distillation step is still necessary in order to achieve the desired separation effect. Despite the two-stage procedure the operating costs for separating the water and solvent are thereby reduced compared to the prior art. A particularly preferred embodiment of the present invention accordingly relates to a process for the catalytic epoxidation of propene in which a) in a reaction step the propene is reacted with aqueous hydrogen peroxide in methanol in the presence of a titanium silicalite catalyst, b) the product stream from the reaction step is optionally passed to a pressure release step, and c) the product stream is then separated, without prior distillative separation, in a pre-evaporator having at most 5 theoretical separation steps into an overhead product containing propene, propene oxide and methanol, and into a bottom product containing methanol and water, 20 to 60% of the total amount of methanol introduced into the product stream being removed with the overhead product and the residue remaining in the bottom product, d) the overhead product from step c) is at least partially condensed, the condensate containing, optionally after stripping out propene and any propane present  0–12 wt. % propene,  0–5 wt. % propane, 15–75 wt. % propene oxide, 25–85 wt. % methanol and  0–3 wt. % water, and e) the condensate from step d) is subjected to an extractive distillation, wherein e1) the condensate is added to a middle section of an extractive distillation column, e2) water is added to the extractive distillation column at a point above the point at which the condensate enters, e3) propene oxide is distilled off at the head of the column, and e4) a bottom product containing methanol and water is removed. The bottom product from the pre-evaporator is optionally combined with other solvent streams recovered in working-up stages as described above and is subjected to the hydrogenation step of the present invention. The pH of the product resulting from the hydrogenation is adjusted to be below 7 and is then separated in a further distillation step into the solvent, which is returned to the epoxidation reaction, and into a mixture of water and high boiling point byproducts, which is either worked up further or is discharged. When using a suspended titanium silicalite catalyst the catalyst is recovered from the bottom product of the pre-evaporator by solid/liquid separation, for example by filtration or centrifugation, whereby the solid/liquid separation is carried out prior to the hydrogenation of the solvent stream. A separation of the catalyst at this point of the process is particularly advantageous since the propene oxide, which represents a health hazard, has at this point already been separated and less stringent requirements are therefore placed on industrial safety, which considerably simplifies the overall process and makes it much more cost-effective. The advantages of the present invention will be apparent in view of the following examples. COMPARATIVE EXAMPLE A titanium-silicate catalyst was employed in all examples. The titanium-silicate powder was shaped into 2 mm extrudates using a silica sol as binder in accordance with example 5 in EP-A 1 138 387. The H 2 O 2 employed was prepared according to the anthraquinone process as a 40 wt-% aqueous solution. Epoxidation is carried out continuously in a reaction tube of 300 ml volume, a diameter of 10 mm and a length of 4 m. The equipment is furthermore comprised of three containers for liquids and relevant pumps and a liquid separating vessel. The three containers for liquids comprised methanol, the 40% H 2 O 2 and propene. The 40% H 2 O 2 was adjusted with ammonia to a pH of 4.5. The reaction temperature is controlled via an aqueous cooling liquid circulating in a cooling jacket whereby the cooling liquid temperature is controlled by a thermostat. The reactor pressure was 25 bar absolute. Mass flow of the feeding pumps was adjusted to result in a propene feed concentration of 21.5 wt-%, a methanol feed concentration of 57 wt-% and an H 2 O 2 feed concentration of 9.4 wt-%. The reactor was operated in down-flow operation mode. The cooling jacket temperature was 41° C., the total mass flow was 0.35 kg/h and the maximum temperature was 59° C. Product output was determined by gas chromatography and the H 2 O 2 conversion by titration. The catalyst selectivity was calculated on the basis of gas chromatographical analysis of the propene oxygenates as the ratio of the amount of propene oxide formed relative to the amount of all propene oxygenates formed. Initial H 2 O 2 conversion was 96% at a catalyst selectivity of 96%. The reaction mixture obtained from the reaction after release of pressure was separated in the pre-evaporation stage into an overhead product containing propene, propane, propene oxide and methanol, and a bottom product containing methanol, propylene glycol monomethyl ethers, propylene glycol, water and high boiling point compounds and non-converted hydrogen peroxide. A liquid condensate that contains propene oxide and methanol as well as propene and propane dissolved therein was obtained from the vapour state overhead product. The uncondensed stream, which substantially consisted of propene and propane, was returned to the epoxidation reaction. The propene and propane dissolved in the condensate were stripped from the latter in the C3 stripper and returned in the vapour state together with the stream to the partial condensation stage. The stream, which consisted substantially of propene oxide and methanol and had been freed from propene and propane, was separated in an extractive distillation in which water was fed in as extraction agent immediately underneath the head of the column, into a propene oxide crude product that consisted initially of more than 99.5%, of propene oxide, and into a bottom product that consisted substantially of methanol and water, the water content being less than 20%. The bottom product was returned as solvent to the epoxidation reaction. The bottom product obtained in the pre-evaporator was separated in a distillation stage at a pressure of 2 bars abs. using a continuously running column having 35 stages at a reflux ratio of 2 for recovering methanol, into an overhead product that consisted of more than 95% of methanol, and into a bottom product consisting of propylene glycol monomethyl ethers, propylene glycol, water, high boiling point compounds and only traces of hydrogen peroxide. The overhead product was continuously returned as solvent to the epoxidation reaction. After 500 h running the epoxidation process the cooling temperature in the reaction step had to be increased to 50° C. to maintain the conversion constant at 95% and the catalyst selectivity dropped to 90%. The propene oxide stream contained 2% acetaldehyde, 0.5% methylformate and 0.2% dimethoxymethane. EXAMPLE 1 The Comparative Example was repeated with the exception that the bottom product obtained in the pre-evaporator stage was directed to a trickle-bed reactor for continuous hydrogenation. The hydrogenation reactor had an interior volume of 150 ml and was filled with a hydrogenation catalyst in form of extrudates with 2.3 mm diameter comprising 2% Ru on activated carbon (The catalyst was prepared according to the incipient wetness method using RuCl 3 , “Preparation of Catalyst”, Demon, B. et al., Elsevier, Amsterdam, 1976, page 13). The hydrogenation was performed at 140° C. and 40 bar abs at a hydrogen flow rate of 10 ml/h. The hydrogenated product was continuously removed and had a pH of 9. The pH was reduced to be below 7 by adding sulfuric acid prior to entering the final distillation step according to the comparative example. After 500 h running the epoxidation process the cooling temperature in the reaction step was 42° C. and the H 2 O 2 conversion was still 96% at a catalyst selectivity of 96%. The propene oxide stream contained 0.07% acetaldehyde, 20 ppm methylformate and 10 ppm dimethoxymethane. As can be seen from the comparison of both examples the activity of the epoxidation catalyst even after 500 h running the process was only very marginally reduced if the solvent stream was hydrogenated prior to recycling the solvent to the reaction stage. In contrast thereto without hydrogenating the solvent stream a considerable reduction in catalyst performance is observed, which requires a gradual increase in the reaction temperature in order to maintain a constant hydrgen peroxide conversion. The effect on product quality is even more dramatic. Thus it is shown that hydrogenation of the solvent stream to be recycled to the epoxidation process leads to considerably reduced catalyst deactivation and improved product quality. EXAMPLE 2 The epoxidation reaction was performed as described for the Comparative Example. The bottom product obtained in the pre-evaporation was analyzed and subjected to the hydrogenation as described for Example 1. The composition of the hydrogenation feed and product are given in Table 1. Apart from hydrogen peroxide, the feed stream was free of other peroxy compounds. TABLE 1 Hydrogenation, Feed & Product Composition Hydrogenation Hydrogenation Feed [%] Product [%] Formaldehyde 0.06 0.00 Acetaldehyde 0.09 0.01 Methanol 72.17 71.92 Ethanol 0.37 0.49 1,2-Dimethoxyethane 0.54 0.59 1-Methoxypropanol-2 0.26 0.26 2-Methoxypropanol-1 0.19 0.19 1,2-Propandiol 0.21 0.23 Others 0.18 0.23 Water 26.19 26.60 Hydrogen Peroxide 0.28 0.00 pH 4.04 9.36 As is evident from Table 1, by means of hydrogenating the solvent stream, carbonyl compounds like acetaldehyde and formaldehyde are substantially and selectively removed. There is no substantial hydrogenolysis of alcohols like methanol or propandiol. In addition, hydrogen peroxide is completely removed.
A process for the epoxidation of olefins which includes i) reacting an olefin with hydrogen peroxide in presence of an epoxidation catalyst and an alcoholic solvent; ii) separating product olefin oxide and unreacted olefin from the reaction product of step i); iii) recovering a stream comprising the alcoholic solvent; and iv) subjecting the recovered stream of step iii) to hydrogenation.
Briefly outline the background technology and the problem the invention aims to solve.
[ "REFERENCE TO A RELATED APPLICATION This application claims the benefit of our provisional patent application 60/376,845 filed May 2, 2002, which is relied on and incorporated herein by reference.", "The present invention relates to a process for the epoxidation of olefins, in particular to the working up of the product stream from the epoxidation reaction.", "PRIOR ART From EP-A 100 118 it is known that propene can be converted with hydrogen peroxide into propene oxide if titanium silicalite is used as catalyst.", "The reaction is preferably carried out in the presence of a water-miscible solvent in order to improve the solubility of propene in the reaction mixture.", "Preferably solvents are used that have a boiling point between the boiling points of propene oxide and water in order to be able to separate the solvent from the reaction mixture by a distillation stage and recycle it to the reaction.", "Methanol is preferably used as solvent.", "WO-A 99/07690 describes a process for the purification of a methanol-containing product stream from the epoxidation of propene that also contains acetaldehyde as an impurity.", "In this case the crude product stream from the epoxidation is subjected to a fractional distillation, in which connection it is particularly important that methanol is present in sufficient amount in the overhead product in order to achieve a substantially complete transfer of acetaldehyde to the bottom product.", "To this end the concentration of methanol in the overhead product is 2–6 wt.", "A distillation column with 20–60 separation stages and a reflux ratio of between 10:1 and 30:1 is furthermore necessary in order to achieve the best possible quantitative separation of the acetaldehyde.", "This arrangement accordingly involves high investment and operating costs for the distillation column.", "From U.S. Pat. No. 5,849,938 it is known that in the distillative working up of the methanol-containing reaction mixture from the propene epoxidation, the difference in volatilities of propene oxide and methanol can be increased by carrying out the distillation as an extractive distillation using water or propylene glycol as extraction agent.", "The purpose of this extractive distillation is to separate methanol as well as further high boiling point impurities like acetaldehyde as quantitatively as possible from the desired product, namely propene oxide, in one distillation step.", "The bottom stream from the distillation containing methanol, the polar extraction agent and impurities is preferably further worked-up by distillation to remove the polar extraction agent and the methanol fraction is preferably recycled to the epoxidation stage.", "EP-A 1 122 248 discloses a process for the working up of a product stream from the epoxidation of propene that contains propene, propene oxide, methanol and water, by separating this product stream into an overhead product containing propene, propene oxide and methanol, and into a bottom product containing methanol and water, wherein the separation takes place in a pre-evaporator with a maximum of 5 theoretical separation stages and 20 to 60% of the total amount of methanol entrained in the product stream is removed with the overhead product, the residue remaining in the bottom product.", "From the overhead product propene oxide is separated by extractive distillation using preferably water as extraction agent.", "The bottom stream from the extractive distillation comprising methanol and water can be directly recycled to the epoxidation stage.", "From the bottom stream of the pre-evaporation step methanol can be recovered by means of a fractionated distillation and recycled to the epoxidation stage.", "Although this process has considerable advantages in that the loss of propene oxide by secondary reactions in the working up is significantly reduced, it has now been discovered that in an continuous process whereby methanol recovered from the work-up of the reaction product is recycled to the epoxidation stage in a long term view the activity and selectivity of the catalyst in the epoxidation stage is reduced and a build up of impurities in the propene oxide product is observed.", "Therefore it is desired to have a process for the epoxidation of olefins wherein the above discussed disadvantages can be avoided.", "In WO 02/02545 the problem of build up of methyl formate in the product propene oxide is addressed.", "This build up can be reduced if methyl formate is removed from the methanol fraction by fractionated distillation prior to recycling the methanol fraction to the epoxidation stage.", "This reference is totally silent with respect to the problem of catalyst deactivation and it has been discovered that removing of methyl formate alone in a single distillation step as taught in WO 02/02545 would not solve the problem of long term deactivation of the catalyst system.", "Especially 1,1-Dimethoxyethan one of the impurities identified to cause catalyst deactivation has a boiling point almost identical with methanol and can therefore practically not be separated from methanol by means of distillation.", "Furthermore according to the teaching in WO 02/02545 an additional distillation step is necessary and a distillation column having 10 theoretical plates has to be used to achieve desired results contributing to increased investment and process costs.", "Therefore it is an object of the present invention to provide a process for the epoxidation of olefins resulting in a recovered solvent stream of increased purity.", "SUMMARY OF THE INVENTION This object has been attained by a process for the epoxidation of olefins by i) reacting an olefin with hydrogen peroxide in presence of an epoxidation catalyst and an alcoholic solvent;", "ii) separating product olefin oxide and unreacted olefin from the reaction product of step i);", "iii) recovering a stream comprising the alcoholic solvent, characterized by iv) subjecting the recovered stream of step iii) to hydrogenation.", "Preferably the recovered solvent stream comprises less than 2 wt.", "% olefin oxide and less than 1 wt.", "% unreacted olefin, more preferred less than 0.5 wt.", "% olefin oxide and less than 0.1 wt.", "% unreacted olefin and is most preferably substantially free of olefin oxide and unreacted olefin to minimize product losses in the hydrogenation step.", "According to a preferred embodiment of the present invention the process further comprises the steps of v) optionally purifying the solvent stream resulting from the hydrogenation step iv) and vi) reusing the solvent.", "Another preferred embodiment of the present invention refers to a process as defined above, wherein the product stream after separation of olefin oxide and unreacted olefin is subjected to hydrogenation and the alcoholic solvent is separated from the hydrogenated stream.", "During the investigations leading to the present invention the inventors discovered that not only methyl formate present in the solvent stream recycled to the epoxidation stage may have a detrimental effect on the reactivity of the catalyst system.", "Also other impurities like carbonyls, acetals and ketals, such as formaldehyde, acetaldehyde, dimethoxymethan and 1,1-dimethoxyethan lead to the deactivation of the catalyst.", "The inventors have surprisingly discovered that the level of impurities comprised in the solvent stream recovered from the epoxidation reaction can be substantially lowered by hydrogenation of the recovered solvent stream after the majority of the product olefin oxide and non-converted olefin has been removed from the solvent stream.", "When recycling the solvent after subjecting to hydrogenation to the epoxidation stage deactivation of the catalyst system can be considerably reduced.", "Furthermore it has been discovered, that compounds found as by-products and impurities and that are difficult to separate from the valuable products and additionally lead if the solvent is recycled to a deactivation of the catalyst system, are not only formed in the reaction step, but also in subsequent working-up stages.", "The formation of undesired by-products and impurities will especially occur in high temperature working-up stages like distillations when peroxide compounds are still present.", "Peroxides that may occur for example in the product of the epoxidation of propene are hydrogen peroxide and organic peroxides, like 1-hydroperoxy-2-propanol and 2-hydroperoxy-1-propanol that are formed in the reaction stage by the reaction of propene oxide with hydrogen peroxide.", "Thus an important advantage of the present invention is, that by hydrogenation not only impurities that are difficult to separate are converted into compounds that can be more easily separated but that also reactive intermediates that can result in subsequent reactions to impurities that are difficult to separate are removed.", "Thus the present invention is particularly advantageous if the solvent is at least partially recycled to the epoxidation step i), but is not restricted to such an embodiment.", "Alternatively the solvent recovered from the process of the present invention can also be reused in different manners well known by a person skilled in the art.", "DETAILED DESCRIPTION OF THE INVENTION The process according to the present invention is particularly suitable for the epoxidation of olefins having two to six carbon atoms, propene being particularly preferred.", "The epoxidation reaction of olefins according to the invention is described hereinafter with the example of propene as preferred olefin.", "The epoxidation reaction with hydrogen peroxide is carried out in the presence of a titanium silicalite catalyst in an alcoholic solvent.", "For the epoxidation of propene a solvent is preferably chosen whose boiling point is between the boiling points of propene oxide and water.", "Suitable solvents include, lower aliphatic alcohols, for example methanol, ethanol or tert.", "-butanol.", "Methanol is preferably used as solvent.", "Due to recycling of substances in the process, the solvent used may contain 0 to 20 wt.", "% of water.", "Hydrogen peroxide is used as an aqueous solution containing 10 to 70 wt.", "% of hydrogen peroxide.", "A hydrogen peroxide crude product obtained from the extraction step of the anthraquinone process and containing 30 to 45 wt.", "% of hydrogen peroxide is preferably used.", "Alternatively, hydrogen peroxide solutions in alcohols, preferably in methanol can be used.", "These alcoholic solutions can be prepared by reaction of hydrogen and oxygen in presence of a noble metal catalyst and the alcohol.", "Propene may be used mixed with propane in an amount of between 0 and 10 vol.", "% of propane.", "Crystalline, titanium-containing zeolites especially those of the composition (TiO 2 ) x (SiO 2 ) 1−x where x is from 0.001 to 0.05 and having a MFI or MEL crystalline structure, known as titanium silicalite-1 and titanium silicalite-2, are suitable as catalysts for the epoxidation process according to the invention.", "Such catalysts may be produced for example according to the process described in U.S. Pat. No. 4,410,501.", "The titanium silicalite catalyst may be employed as a shaped catalyst in the form of granules, extrudates or shaped bodies.", "For the forming process the catalyst may contain 1 to 99% of a binder or carrier material, all binders and carrier materials being suitable that do not react with hydrogen peroxide or with the epoxide under the reaction conditions employed for the epoxidation.", "Extrudates with a diameter of 1 to 5 mm are preferably used as fixed bed catalysts.", "In one embodiment of the invention the titanium silicalite catalyst is suspended in the reaction mixture during the reaction.", "The catalyst is then used in the form of a powder or in the form of a suspendable granular material that has been produced by forming in a manner known per se, for example by spray drying or fluidised bed granulation.", "When using a suspended catalyst, flow mixing reactors, for example stirred tank reactors or recycle reactors, as well as non-flow mixing reactors, for example tubular flow reactors, may be used for the reaction.", "A cascade consisting of one to three flow mixing reactors and a non-flow mixing reactor connected downstream is preferably used.", "In another embodiment of the invention the titanium silicalite catalyst is used as a fixed bed over which a mixture of the feedstock materials is passed.", "The catalyst is then used in the form of formed bodies that have been produced in a manner known per se, for example by extrusion with the addition of binders.", "When using a fixed bed catalyst, reactors with bubble column characteristics can be used, i.e. a continuous liquid phase and a dispersed gaseous phase simultaneously flow through the reactor.", "Alternatively the reaction can be run in a trickle bed modus.", "The epoxidation reaction is carried out at temperatures between 0 and 80° C., preferably between 40 and 65° C., and at elevated pressures of atmospheric pressure to 50 bar preferably 10 to 20 bar under an atmosphere substantially consisting of propene.", "The propene is used in excess and the residence time in the reactor is chosen so that a hydrogen peroxide conversion of more than 90%, preferably more than 95%, is achieved.", "The amount of solvent used is preferably chosen so as to achieve a ratio of 1 to 5 parts by weight of solvent to one part by weight of aqueous hydrogen peroxide solution.", "Before the working up stage the pressure of the reaction mixture is preferably released in a pressure release stage to the pressure employed in the working up of the propene oxide.", "Part of the propene dissolved in the reaction mixture and possibly propane is gassed out.", "The resultant gas is recompressed via a compressor to the pressure prevailing in the reactor and is returned to the reaction.", "The propene oxide still contained in the gas is preferably recovered by cooling and partial condensation after the compression.", "The work-up of the reaction product can be conducted in conventional way such as multiple distillation steps as well know in the art as long as at some stage of the entire working-up procedure at least one solvent stream is recovered.", "The at least one solvent stream or a combined stream resulting from different stages of the working-up procedure is subjected to a hydrogenation step according to the present invention.", "According to a preferred embodiment of the present process in step iv) the recovered solvent stream is subjected to a heterogeneous catalytic hydrogenation at a hydrogen partial pressure of 0.5 to 30 MPa.", "It is particularly preferred to conduct the hydrogenation step at a temperature in the range of 80° C. and 150° C., preferably 100° C. to 180° C. and at a hydrogen partial pressure of 1 to 25 MPa.", "Suitable catalysts are selected from supported catalysts comprising one or more of metals selected from the group consisting of Ru, Rh, Pd, Pt, Ag, Ir, Fe, Cu, Ni and Co. Alternatively Raney Nickel and Raney Cobalt both optionally being doped with one or more of the above mentioned can be used.", "The catalyst support is preferably selected from activated carbon and metal oxides selected from SiO 2 , TiO 2 , ZrO 2 and Al 2 O 3 , mixed oxides comprising at least two of Si, Al, Ti and Zr and mixtures thereof.", "In the epoxidation process of the present invention, carbonyl compounds are formed in the epoxidation reactor or during subsequent working-up stages, especially distillation stages.", "After separating the product propylene oxide, propene and other light boilers like methylformate from the reaction mixture, a stream comprising most of the solvent methanol, water, residual hydrogen peroxide and carbonyl compounds is obtained.", "In addition to the carbonyl compounds and the alcoholic solvent the corresponding acetals and ketals are also present.", "Therefore, according to a preferred embodiment of the present invention, a hydrogenation system including reactor, catalyst and reaction conditions is chosen to hydrogenate the carbonyl compounds as well as the corresponding acetals, like formals, hemiformals, ketals and hemiketals.", "These carbonyl compounds can be hydrogenated by using metal catalysts.", "These metals are preferably Nickel or precious metals.", "In case of precious metals, the metals are supported.", "The catalyst support can be any solid which is inert and does not deteriorate under the reaction conditions.", "Examples are silica, alumina, titania, zirconia, clays, calcium carbonate or mixed oxides like silica-alumina.", "Especially suitable catalysts for hydrogenating the carbonyl compounds, acetals and ketals are carbon with precipitated platinum, palladium, iridium or ruthenium.", "Preferred is ruthenium.", "The catalyst support can be in the form of spheres, pellets, tablets, granules, extrudates, balls etc.", "The precious metal loaded onto the support can be in the range of 0.01 to 50 wt.", "Preferred is the range of 0.1 to 5% based on the weight of the support.", "The precious metal catalyst can be prepared by any state of the art method.", "The metal can be distributed over the support surface by reducing the corresponding metal salts.", "These metal salts can be oxides, chlorides, nitrates, hydroxides, carbonates etc.", "These catalysts can be acquired commercially from producers like Degussa or Johnson Matthey (see Johnson Matthey The Catalyst Technical Handbook 2001, page 22 and 23).", "Furthermore, to ensure hydrogenation of carbonyl compounds and corresponding acetals and ketals, it is preferred to adjust the temperature in the hydrogenation step to be at least 80° C., more preferably in the range of from 100 to 150° C. and the hydrogen partial pressure to be at least 2 MPa, more preferably in the range of from 3 to 5 MPa.", "The hydrogenation reactor is preferably operated without additional cooling (adiabatic reactor).", "The hydrogenation can be carried out continuously or batch-wise e.g., in a suspension method or a fixed-bed method.", "It is especially preferred to use a trickle-bed reactor.", "Such reactors are well known.", "The fixed-bed catalysts to be used therein are preferably pellets with a diameter of 0.5 to 5 mm, especially 1 to 3 mm and with a length of 1 to 10 mm.", "The noble-metal content is in the customary range, preferably 0.5 to 5% by weight.", "By hydrogenation of a solvent stream resulting for example from the epoxidation of propene with hydrogen peroxide in a methanol solvent, wherein propene oxide and propene have been substantially removed, hydrogen peroxide is converted to water, 1-hydroperoxy-2-propanol, 2-hydroperoxy-1-propanol and hydroxyacetone are converted to 1,2-propanediol, formaldehyde is converted to methanol, acetaldehyde is converted to ethanol and 1,1-dimethoxyethane is converted to methanol and ethanol.", "Methylformate and dimethoxymethane will under the above specified conditions not be converted or only to a lesser extent.", "The alcoholic solvent stream resulting from the hydrogenation step can by either directly reused or if necessary for specific applications additionally purified for example by distillation prior to reusing the alcoholic solvent.", "After hydrogenation and prior to distillation it is preferred to adjust the pH of the alcoholic solvent stream to be below 7.", "This can be done by any acid that does not interfere with subsequent process steps like sulfuric acid.", "According to the most preferred embodiment the solvent stream purified according to the teaching of the present invention is recycled to the epoxidation stage i) of the present process.", "Most importantly, in a continuous process deactivation of the epoxidation catalyst can be at least considerably reduced by treating the solvent stream to be recycled in a hydrogenation step.", "Additionally the build up of low boiling impurities in the propene oxide product that are difficult to remove is substantially reduced resulting in an improved product quality.", "Additionally it has been surprisingly found that in a process wherein the solvent for example methanol is recycled to the reaction stage i) a build-up of methylformate and dimethoxymethane is not observed, although these compounds are not or only to a lesser extent converted in the hydrogenation reaction under the above specified conditions.", "Without wishing to be bound by theory it is believed that hydrogenation removes peroxides which otherwise would react in subsequent working-up stages forming methylformate, dimethoxymethane and precursors to these compounds.", "At the same time, hydrogenation also removes said and/or other precursors to methylformate and dimethoxymethane, like formaldehyde, and prevents them from being recycled to the reaction stage with the solvent.", "Consequently the present invention leads to a more effective and cost-efficient epoxidation process, since the operation cycle between regeneration cycles of the epoxidation catalyst can be considerably prolonged and to an improved product quality.", "These advantages can be achieved by a relatively simple measure of a hydrogenation step.", "Moreover the hydrogenation step can be easily integrated into the work-up procedure of the epoxidation product.", "According to one embodiment of the present invention the reaction mixture is separated in a pre-evaporator into an overhead product containing propene, possibly propane, propene oxide and solvent, and into a bottom product containing solvent, water, non-converted hydrogen peroxide higher boiling point by-products, such as for example propylene glycol, and if a suspension method is used for the epoxidation step suspended titanium silicalite catalyst.", "The pre-evaporator preferably has at most only 5 theoretical separation steps and is designed so that the stripping section corresponds to a simple evaporation and the remaining separation effect is achieved in the rectification section.", "The pre-evaporator is operated at a reflux ratio of at most 1.5 and if desired may also be operated totally without reflux.", "The pressure in the pre-evaporator is preferably chosen in the range from 1.5 to 8 bar in order to be able to condense the propene oxide with cooling water from the overhead product without having to use a cooling unit.", "The pre-evaporator is operated so that between 10 and 60% of the amount of solvent fed in with the reaction mixture is removed with the overhead product and the residue remains in the bottom product.", "In the operational procedure according to the invention more than 95%, typically more than 98% and preferably more than 99% of the propene oxide fed in is contained in the overhead product, and more than 90%, typically more than 97% and preferably more than 99% of the water fed in is contained in the bottom product.", "In this embodiment the bottom product from the pre-evaporator is subjected to the hydrogenation step of the present invention.", "The product stream fed to the pre-evaporator normally contains 0.5–20 wt.", "% of propene, 0–4 wt.", "% of propane, 5–35 wt.", "% of propene oxide, 35–80 wt.", "% of methanol, 5–40 wt.", "% of water, 0.1–8 wt.", "% of higher boiling point by-products, 0.1 to 5 wt.", "% hydrogen peroxide and 0–5 wt.", "% of titanium silicalite catalyst.", "This product stream is separated in the process according to the invention into an overhead product containing 1–40 wt.", "% of propene, 0–10 wt.", "% of propane, 15–75 wt.", "% of propene oxide, 20–85 wt.", "% of methanol and 0–5 wt.", "% of water, and into a bottom product containing 0–2 wt.", "% of propene oxide, 0–1 wt.", "% of propene, 30–80 wt.", "% of methanol, 15–65 wt.", "% of water, 0.1–10 wt.", "% of higher boiling point byproducts, 0.1–5 wt.", "% of hydrogen peroxide and 0–10 wt.", "% of titanium silicalite catalyst.", "The overhead product is preferably only partially condensed and the uncondensed propene, possibly mixed with propane, is recompressed via a compressor to the pressure prevailing in the reaction part and is recycled to the reaction, the propene oxide still contained in the gas preferably being removed by partial condensation after compression.", "The propene still dissolved in the condensate and possibly propane are stripped out from the condensate in a C3 stripper and the stripped-out gas is recycled to the partial condenser.", "The mixture of propene oxide and solvent contained in the C3 stripper is separated by distillation into a propene oxide crude product, which can be purified further in a manner known per se, and the solvent, which is recycled to the epoxidation reaction directly or can be combined with other solvent streams from different working-up stages and subjected to hydrogenation prior to recycling the solvent to the reaction stage.", "In a particularly preferred embodiment the mixture of propene oxide and solvent, preferably methanol, obtained from the C3 stripper is worked up further by extractive distillation to achieve as quantitative a separation as possible of the solvent.", "In this connection the mixture of propene oxide and methanol is added to the middle section of an extractive distillation column, preferably at a point corresponding to ⅓ of the total number of theoretical trays counting from the bottom, and a polar solvent with hydroxyl functionality and having a boiling point higher than that of methanol is added to the extractive distillation column at a point above the point at which the condensate enters, preferably at a point corresponding to ⅔ of the total number of theoretical trays counting from the bottom.", "The propene oxide crude product is distilled off at the head of the column and a mixture of methanol and the polar solvent is extracted as bottom product.", "The polar solvent is selected from water, glycols, glycol ethers and mixtures thereof.", "The preferred polar solvent is water since in this case the mixture of water and methanol can be either recycled directly to the reaction step without further purification or preferably is combined with other solvent streams and is hydrogenated prior to recycling.", "In order to achieve as complete a separation of the methanol as possible, a column with 25–100 theoretical separation steps and with a reflux ratio of 1–4 is already sufficient on account of the concentration of the propene oxide in the overhead product, the mathematical product of the number of separation steps and the reflux ratio typically being 75 to 125.", "On account of the pre-evaporation only a very small reflux ratio for the extractive distillation step is still necessary in order to achieve the desired separation effect.", "Despite the two-stage procedure the operating costs for separating the water and solvent are thereby reduced compared to the prior art.", "A particularly preferred embodiment of the present invention accordingly relates to a process for the catalytic epoxidation of propene in which a) in a reaction step the propene is reacted with aqueous hydrogen peroxide in methanol in the presence of a titanium silicalite catalyst, b) the product stream from the reaction step is optionally passed to a pressure release step, and c) the product stream is then separated, without prior distillative separation, in a pre-evaporator having at most 5 theoretical separation steps into an overhead product containing propene, propene oxide and methanol, and into a bottom product containing methanol and water, 20 to 60% of the total amount of methanol introduced into the product stream being removed with the overhead product and the residue remaining in the bottom product, d) the overhead product from step c) is at least partially condensed, the condensate containing, optionally after stripping out propene and any propane present 0–12 wt.", "% propene, 0–5 wt.", "% propane, 15–75 wt.", "% propene oxide, 25–85 wt.", "% methanol and 0–3 wt.", "% water, and e) the condensate from step d) is subjected to an extractive distillation, wherein e1) the condensate is added to a middle section of an extractive distillation column, e2) water is added to the extractive distillation column at a point above the point at which the condensate enters, e3) propene oxide is distilled off at the head of the column, and e4) a bottom product containing methanol and water is removed.", "The bottom product from the pre-evaporator is optionally combined with other solvent streams recovered in working-up stages as described above and is subjected to the hydrogenation step of the present invention.", "The pH of the product resulting from the hydrogenation is adjusted to be below 7 and is then separated in a further distillation step into the solvent, which is returned to the epoxidation reaction, and into a mixture of water and high boiling point byproducts, which is either worked up further or is discharged.", "When using a suspended titanium silicalite catalyst the catalyst is recovered from the bottom product of the pre-evaporator by solid/liquid separation, for example by filtration or centrifugation, whereby the solid/liquid separation is carried out prior to the hydrogenation of the solvent stream.", "A separation of the catalyst at this point of the process is particularly advantageous since the propene oxide, which represents a health hazard, has at this point already been separated and less stringent requirements are therefore placed on industrial safety, which considerably simplifies the overall process and makes it much more cost-effective.", "The advantages of the present invention will be apparent in view of the following examples.", "COMPARATIVE EXAMPLE A titanium-silicate catalyst was employed in all examples.", "The titanium-silicate powder was shaped into 2 mm extrudates using a silica sol as binder in accordance with example 5 in EP-A 1 138 387.", "The H 2 O 2 employed was prepared according to the anthraquinone process as a 40 wt-% aqueous solution.", "Epoxidation is carried out continuously in a reaction tube of 300 ml volume, a diameter of 10 mm and a length of 4 m. The equipment is furthermore comprised of three containers for liquids and relevant pumps and a liquid separating vessel.", "The three containers for liquids comprised methanol, the 40% H 2 O 2 and propene.", "The 40% H 2 O 2 was adjusted with ammonia to a pH of 4.5.", "The reaction temperature is controlled via an aqueous cooling liquid circulating in a cooling jacket whereby the cooling liquid temperature is controlled by a thermostat.", "The reactor pressure was 25 bar absolute.", "Mass flow of the feeding pumps was adjusted to result in a propene feed concentration of 21.5 wt-%, a methanol feed concentration of 57 wt-% and an H 2 O 2 feed concentration of 9.4 wt-%.", "The reactor was operated in down-flow operation mode.", "The cooling jacket temperature was 41° C., the total mass flow was 0.35 kg/h and the maximum temperature was 59° C. Product output was determined by gas chromatography and the H 2 O 2 conversion by titration.", "The catalyst selectivity was calculated on the basis of gas chromatographical analysis of the propene oxygenates as the ratio of the amount of propene oxide formed relative to the amount of all propene oxygenates formed.", "Initial H 2 O 2 conversion was 96% at a catalyst selectivity of 96%.", "The reaction mixture obtained from the reaction after release of pressure was separated in the pre-evaporation stage into an overhead product containing propene, propane, propene oxide and methanol, and a bottom product containing methanol, propylene glycol monomethyl ethers, propylene glycol, water and high boiling point compounds and non-converted hydrogen peroxide.", "A liquid condensate that contains propene oxide and methanol as well as propene and propane dissolved therein was obtained from the vapour state overhead product.", "The uncondensed stream, which substantially consisted of propene and propane, was returned to the epoxidation reaction.", "The propene and propane dissolved in the condensate were stripped from the latter in the C3 stripper and returned in the vapour state together with the stream to the partial condensation stage.", "The stream, which consisted substantially of propene oxide and methanol and had been freed from propene and propane, was separated in an extractive distillation in which water was fed in as extraction agent immediately underneath the head of the column, into a propene oxide crude product that consisted initially of more than 99.5%, of propene oxide, and into a bottom product that consisted substantially of methanol and water, the water content being less than 20%.", "The bottom product was returned as solvent to the epoxidation reaction.", "The bottom product obtained in the pre-evaporator was separated in a distillation stage at a pressure of 2 bars abs.", "using a continuously running column having 35 stages at a reflux ratio of 2 for recovering methanol, into an overhead product that consisted of more than 95% of methanol, and into a bottom product consisting of propylene glycol monomethyl ethers, propylene glycol, water, high boiling point compounds and only traces of hydrogen peroxide.", "The overhead product was continuously returned as solvent to the epoxidation reaction.", "After 500 h running the epoxidation process the cooling temperature in the reaction step had to be increased to 50° C. to maintain the conversion constant at 95% and the catalyst selectivity dropped to 90%.", "The propene oxide stream contained 2% acetaldehyde, 0.5% methylformate and 0.2% dimethoxymethane.", "EXAMPLE 1 The Comparative Example was repeated with the exception that the bottom product obtained in the pre-evaporator stage was directed to a trickle-bed reactor for continuous hydrogenation.", "The hydrogenation reactor had an interior volume of 150 ml and was filled with a hydrogenation catalyst in form of extrudates with 2.3 mm diameter comprising 2% Ru on activated carbon (The catalyst was prepared according to the incipient wetness method using RuCl 3 , “Preparation of Catalyst”, Demon, B. et al.", ", Elsevier, Amsterdam, 1976, page 13).", "The hydrogenation was performed at 140° C. and 40 bar abs at a hydrogen flow rate of 10 ml/h.", "The hydrogenated product was continuously removed and had a pH of 9.", "The pH was reduced to be below 7 by adding sulfuric acid prior to entering the final distillation step according to the comparative example.", "After 500 h running the epoxidation process the cooling temperature in the reaction step was 42° C. and the H 2 O 2 conversion was still 96% at a catalyst selectivity of 96%.", "The propene oxide stream contained 0.07% acetaldehyde, 20 ppm methylformate and 10 ppm dimethoxymethane.", "As can be seen from the comparison of both examples the activity of the epoxidation catalyst even after 500 h running the process was only very marginally reduced if the solvent stream was hydrogenated prior to recycling the solvent to the reaction stage.", "In contrast thereto without hydrogenating the solvent stream a considerable reduction in catalyst performance is observed, which requires a gradual increase in the reaction temperature in order to maintain a constant hydrgen peroxide conversion.", "The effect on product quality is even more dramatic.", "Thus it is shown that hydrogenation of the solvent stream to be recycled to the epoxidation process leads to considerably reduced catalyst deactivation and improved product quality.", "EXAMPLE 2 The epoxidation reaction was performed as described for the Comparative Example.", "The bottom product obtained in the pre-evaporation was analyzed and subjected to the hydrogenation as described for Example 1.", "The composition of the hydrogenation feed and product are given in Table 1.", "Apart from hydrogen peroxide, the feed stream was free of other peroxy compounds.", "TABLE 1 Hydrogenation, Feed &", "Product Composition Hydrogenation Hydrogenation Feed [%] Product [%] Formaldehyde 0.06 0.00 Acetaldehyde 0.09 0.01 Methanol 72.17 71.92 Ethanol 0.37 0.49 1,2-Dimethoxyethane 0.54 0.59 1-Methoxypropanol-2 0.26 0.26 2-Methoxypropanol-1 0.19 0.19 1,2-Propandiol 0.21 0.23 Others 0.18 0.23 Water 26.19 26.60 Hydrogen Peroxide 0.28 0.00 pH 4.04 9.36 As is evident from Table 1, by means of hydrogenating the solvent stream, carbonyl compounds like acetaldehyde and formaldehyde are substantially and selectively removed.", "There is no substantial hydrogenolysis of alcohols like methanol or propandiol.", "In addition, hydrogen peroxide is completely removed." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] The present application claims the benefit of priority to the U.S. provisional application of the same title having application Ser. No. 61/287,635, which was filed on Dec. 17, 2009, which is incorporated herein by reference. BACKGROUND OF INVENTION [0002] The present invention relates to the provision of energy to wireless telecommunications systems, and in particular to such provision by wind powered generators, as well as to the generation of electrical power from wind energy. [0003] Wireless telecommunications technology is especially attractive to remote communities lacking an existing signal wire system, and in particular to developing countries that have no or minimal telecommunications outside of major cities. [0004] However, while cellular wireless telecommunication is well advanced, the locations most lacking in these services also frequently lack connection to a reliable electrical power distribution infrastructure to provide power to the electronic systems, such as the radio frequency and microwave transceivers, deployed on cellular telecommunication transmission towers. [0005] It is therefore a first object of the present invention to provide a means for powering the electronics systems deployed on remote cellular telecommunication transmission towers as well as provide a reliable power source for remote cell communication towers [0006] It is a further object of the invention to reduce the installed cost of generating electrical power by taking advantage of telecommunication infrastructure. SUMMARY OF INVENTION [0007] In the present invention, the first object is achieved by providing a tower structure comprising, a substantially vertical support tower having a top portion and a lower mounting base and at least a portion with a central vertical lumen or opening therein between the top portion and the lower mounting base thereof, a vertically arrayed wind turbine (VAWT), having a central mounting hub and a plurality of turbine blades coupled thereto to provide free rotation about the central opening of said substantially vertical support tower, an electrical generator rotationally coupled to said central mounting hub, at least one of a receiver, transmitter or transceiver of electromagnetic radiation supported by said a substantially vertical support tower and disposed above said VAWT, at least one cable for power transmission extending downward from the generator, being electrically coupled thereto to the lower mounting base, and at least one cable extending upward from the lower mounting base through the central mounting hub of the VAWT to connect in signal communication with said at least one of an receiver, transmitter or transceiver. [0008] The above and other objects, effects, features, and advantages of the present invention will become more apparent from the following description of the embodiments thereof taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIG. 1 is a perspective view of a first embodiment of the invention. [0010] FIG. 2 is a perspective view of a second embodiment of the invention. [0011] FIG. 3 is a perspective view of a second embodiment of the invention. [0012] FIGS. 4A and B is a plan view of section A-A of FIG. 1 illustrating alternative positions of the antenna blades [0013] FIG. 5 is cross-section elevation of a portion of the embodiment shown in FIG. 1-3 . [0014] FIG. 6 is cross-section elevation of a third embodiment of the invention. [0015] FIG. 7 is cross-section elevation of a fourth embodiment of the invention. [0016] FIG. 8 is a plan section view of a portion of the tower and generator/alternator showing a preferred method of assembly, whereas FIG. 8B is a cross-sectional elevation thereof. DETAILED DESCRIPTION [0017] Referring to FIGS. 1 through 8 , wherein like reference numerals refer to like components in the various views, there is illustrated therein a new and improved antenna mounted wind power generator, generally denominated 100 herein. [0018] In accordance with the present invention, FIG. 1 illustrates a first embodiment of the antenna mounted wind power generator 100 that comprises an antenna assembly 105 , consisting of generally conventional antenna devices, in this case panel type transceivers 140 of electromagnetic radiation that transmit and receive encoded RF or microwave signal information. This antenna assembly 105 is mounted at the top of the antenna support tower 110 and disposed above the vertically arrayed wind turbine (VAWT) 120 . In this embodiment the antenna support tower 110 is a tubular tower, having a generally circular cross-section. At least a portion of the antenna support tower 110 below the antenna assembly 105 has a lumen or central vertical opening 111 , although it appears solid on the outside. The VAWT 120 is mounted on the antenna support tower 110 below the antenna assembly 105 , being disposed for free rotation about the central opening 111 via at least one pairs of two hubs 121 and 121 ′ that are coupled to the antenna support tower 110 . Since this particular VAWT 120 has a pair of coupled blade assemblies 125 and 126 stacked on each other there are 2 hubs, 121 being disposed at the top of the upper blade assembly 125 and 121 ′ being disposed at the bottom of the lower blade assembly 126 . Radial struts 124 extend outward from each hub 121 and connect to horizontally disposed blade support rings 122 , 122 ′ and 122 ″′. The blades 123 are vertically disposed and connect to each blade assembly 125 and 126 by the blade support rings 122 and 122 ′ or 122 ′ and 122 ″, at their top and bottom Thus, each of the blade assemblies 125 and 126 has in common the centrally disposed of the three blade support rings 122 ′, which is not connected to the antenna support tower 105 directly. The generator 130 is preferably disposed below hub 121 so that its rotor 132 can be connected to the rotating outer portion of the lower hub 121 that is driven by wind induced rotation of the rings supports 122 by the force acting on the turbine blades 123 . A preferred VWAT architecture is described in US Pat. Appl. no. US 2008/0253889 A1, of Krivcov et al. that published on Oct. 16, 2008 for a VERTICAL AXIS WIND TURBINES, which is incorporated herein by reference. [0019] Alternative designs for VWAT are also disclosed in U.S. Pat. No. 7,329,965 B2 issued to Roberts et al. on Feb. 12, 2008 for an AERODYNAMIC-HYBRID VERTICAL-AXIS WIND TURBINE, which is also incorporated herein by reference. It is not intended that the invention be limited to any particular form of a VAWT. [0020] As the portion of the tower 110 that support the VAWT 120 cannot interfere with the hub rotation, the signal cables 160 that connects a base station 520 to the RF or microwave transceiver 140 runs through the lumen or central vertical opening 111 , as shown in FIG. 5 . The power cable(s) 150 emanate from the generator 130 can run down either the outside of the tower 110 or through the portion of the central opening 111 that extends below the vertical expanse of the VAWT 120 . [0021] Generally speaking VAWT's have particular advantages as compared to deploying horizontal axis wind turbines. This is particularly true for the inventive combination with the antenna system 105 at the top of the tower. The VWAT blades 123 , being oriented in the same direction of the tower 110 are below the antenna 140 and will not shadow or block them in a manner that would attenuate signals. [0022] Further, because the centers of gravity of the VWAT 120 and generator 130 align are both disposed on the central or primary vertical axis of the on the antenna tower 110 , the structural demands of the antenna tower 110 are not expected to be significantly greater than they would be for just the antenna assembly 105 . As a mounting tower is a significant part of the cost of any wind turbine system, using cellular telephone transmission towers reduces the cost to supply electrical power with a wind turbine, which can power the antenna or serve other users in the area. [0023] Further as the preferred embodiment of the VWAT is efficient at generating power in light winds from any direction, the antenna mounted wind generator system is practical and useful to deploy in most locations where the antennas would be sited for communication purposes only. The ability to generate power in light winds from any direction favors using the VWAT generated power to energize the antenna system itself as described further below, as it is more likely that power will be available when needed. However, to the extent there is not always the minimum wind necessary to generate power, back up batteries, or any other energy storage medium for such occasions could at least be of are reduced size to accommodate the rare occasions where there would not be sufficient wind to turn the VWAT. [0024] Further, as VWAT's 120 have lower tip speed of the turbine blades that rotate in a vertical plane about a horizontal shaft they tend to minimize the potential for bird kill. [0025] In the embodiment shown in FIG. 1 , the antenna support tower 110 is an elongated tube of generally circular cross-structure. [0026] In the embodiment shown in FIG. 2 the antenna support tower 110 has an open truss framed tower from the ground until the antenna portion 105 . [0027] In the embodiment shown in FIG. 3 the antenna support tower 110 is an elongated tube of generally circular cross-structure in the lower portion 110 a between the ground and the generator 130 , which is situated just below hub 121 to couple to the rotor 132 ( FIG. 5 ). However, the central portion 110 b of the tower 110 that runs through the VWAT 120 is of a truss type framed construction. One non-limiting example of such a frame construction is illustrated as composed of vertically spaced apart rings held at their outer periphery by a plurality of vertical posts. [0028] FIGS. 4A and 4B illustrate why the embodiment of FIG. 2 is more preferred over that in FIG. 1 . In these figures the wind is coming from the left as indicated by the array of arrows 200 . Each turbine blade 123 creates a lower pressure “shadow” 210 in the region behind it with respect to the wind direction and blade shape. In FIG. 4A , the shadows 210 do not cross the cross-section of the antenna tower inside hub 121 , hence the antenna is subjected to the force of the wind 200 . However, in FIG. 4B , as the blades 123 have rotated with support ring 122 , a blade now casts a lower pressure “shadow” that includes the tower 110 . Thus, with a solid tower, due to its wider cross-section, will be subject to a periodic variation in stress as the VWAT rotates, coming in and out of the shadow 210 . However, if the section of the tower 110 b within the central axis of the VWAT's rotation is generally open constructed from struts, rings or trusses, the pressure variation will be lower although the same “shading” will still occur, as the such constructions present a much small cross-section when not “shaded” in FIG. 4A . [0029] Thus, FIG. 2 and FIG. 3 are more preferred embodiments because they minimize such periodic stress and potential for movement to the antenna 105 . Where a solid tower cross-section is preferred at a least the ground level, the embodiment of FIG. 3 is more preferred as the strut or frame is only visible far from the ground away for the height of the VWAT 120 . [0030] FIG. 5 illustrates in more detail an embodiment for coupling the rotating portion of the hub 121 , to the rotor 131 of generator 130 . The hub 121 that supports the VWAT blades 123 is connected in rotary engagement with the tower 110 by the bearing plate 501 . FIG. 5 also illustrates an additional embodiment in which the power generated by the VWAT, via generator 130 , is transmitted via cable 150 to a battery 510 . The battery 510 optionally powers the base electronic system or unit 520 that is connected to the signal cable 160 . The signal cables 160 convey signal and routing information to the base electronic system for routing to different antennas or land based telecommunication cables. The base electronic signal system need not be located at ground level, and it components can be disturbed in different location with respect to the antenna assembly 105 . Thus, antennas or transceivers 140 are optionally self-powered by the VWAT 120 , or powered by the VWAT 120 via a battery 510 , when either normal (land base power) or wind power is not available due to insufficient breezes. [0031] It should be appreciated that the various embodiment described above have the benefits of reducing the installed cost of generating electrical power by taking advantage of telecommunication infrastructure, that is the necessity of having erected plural remote towers for cellular phone communications. Thus the power generated by VWAT 120 can be used by local users or feed back into the power grid. [0032] VWAT's of the preferred design has several advantages for recharging the batteries of a cell phone base station, or generating electricity in general. As the cell phone towers are likely to be situated by reception criteria, and not specifically to take advantage of locations with steady high wind conditions, the VWAT design is particularly advantageous because it is self starting in low wind conditions. Further, the performance of the VWAT does not depend on the wind direction, in that is omni-directional. Not only does the generator's 130 electrical output not depend on the compass heading of the wind, it also doesn't matter how rapidly it changes direction. Thus, the preferred VWAT turbine still captures wind energy as the wind changes direction, which that is continuously converted to electrical power. Further, the VAWT mass acts as a flywheel, picking up some speed in wind gusts and continuing to rotate in the short periods of low wind. Accordingly, a VWAT of the preferred design can be constantly charging the back-up battery or generating power in a wider range of cell tower location. Unlike Horizontal Axis Wind Turbine (HAWT), there is no requirement for the windmill to “seek” the wind direction. Accordingly another advantage of the invention is the elimination of the expensive and unreliable mechanics related to pointing an HWAT toward the wind. Thus, a VWAT will have a smooth, steady, quiet motion eliminating noise, and reducing energy losses of starting and stopping. Vibrations in the mounting structure are also reduced, while the flywheel effect gives a more constant voltage output to the electronics. Accordingly, the various embodiment of the invention will provide a reliable power source for remote cell communication towers and other users or consumers of power. [0033] It is also expected that the preferred embodiments will not cause interference with RF transmission, as well as provide for easier maintenance to the generator, such as replacing bearings, without the need to depower or terminate RF transmission. [0034] In furtherance of another objective of facilitating maintenance of the RF transmission system 105 , FIG. 6 illustrates a more preferred embodiment in which a tower 110 is hollow and can be entered at or near the ground 1 via a lower access door 601 via portal 611 that allows maintenance personnel 10 to enter and climb up the internal ladder 602 , exiting an upper access door 603 at portal 613 , thus leading them to the panel type transceivers 140 and connecting signal cables 160 that also runs through tower 110 . The ladder 602 can be a series of spaced apart vertical rungs, without the connecting extending horizontal side bars, or any other structure or apparatus that permits self propelled or automated transportation of the maintenance personnel 10 above the VWAT 120 to access the antenna supporting portion of the tower. As shown in this figure, it may be preferable that the tower 120 is a hollow tube below upper access door 603 , but of strut or truss construction above it. [0035] FIG. 7 illustrates an alternative and more preferred embodiment in which the tower 110 is solid but internally hollow to provide access via the internal ladder 602 as in FIG. 6 , however, the exit portal 613 and upper access door 603 are now located below the VWAT 120 , in the lower portion 110 a , such that the upper portion 110 c of the tower 110 below the antenna system 105 , including the panel type transceivers 140 , is of a hollow strut or truss construction structure through which the ladder 602 optionally extends providing access to transceivers 140 while the VWAT 120 rotates. Depending on the strut or truss spacing the ladder need not be a continuous unitary structure, but can be additional foot and handhold members spaced apart the conventional distance of about a foot (about 30 cm), which may include some strut or truss members themselves. [0036] FIG. 8A schematically illustrates in a plan view of a preferred embodiment in which portions of the generator are assembled from arc shaped segments that surround the hollow tower 110 . FIG. 8B is a cross-sectional elevation of the same region. The stator 131 is formed from a plurality of arc shaped stator segments 8131 that are attached to a flange or hub 121 ′ that is coupled to the tower 110 to provide the stationary portion of the generator 130 . The rotor 132 is formed from a plurality of arc shaped rotor segments 8132 that are attached to a flange or hub 121 that is coupled to tower 110 by rotary bearings to form one or more rotor assemblies 131 . One or within each rotor segment 8132 are a plurality of wedge shaped magnets 8032 that alternatively in polarity to provide along with the stator 131 , an axial gap electric dynamo type generator/alternator. In the more preferred embodiment of FIG. 8B , each arc shaped segment 8131 that will form the stator disc 131 has connected serpentine wiring 8031 loops on both sides and is inserted sideways over the rotor disc 132 . The serpentine winding in such a disc is disclosed in U.S. Pat. No. 7,646,132 B2, issued to R. Halstead on Jan. 12, 2010, which is incorporated herein by reference. It should also be appreciated that such arc shaped rotor and stator segment can be pre-assembled into arc shaped units which are then mounted on the appropriate hub structure on the periphery of the tower 110 . Further, one the arc shaped segment of the rotor and stator are coupled to the tower via a hub they can be mechanically coupled to each other for greater stability. [0037] It is also preferred that a magnetic bearing be deployed at the outer extremity or perimeter of the rotor disk 132 , such as that disclosed in the US Pat. Application No. used at the perimeter of the rotor disk 132 , as disclosed in US Patent Publication No. 2009-200883A1, published on Aug. 13, 2009, which is incorporated herein by reference. Such a magnetic bearing assembly can also be assembled in arc shaped segment as described above. [0038] While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be within the spirit and scope of the invention as defined by the appended claims. [0039] For example, the VAWT 120 of antenna assembly 100 may deploy additional pairs of stacked coupled blade assemblies than the two ( 125 and 126 ) shown in FIG. 1-3 , as for example 3 to 4 blade assemblies. In addition, more than 3 individual blades or air foils 123 can be deployed in the 2 or more blades assemblies, as for example 3-5 blades per stacked blade assembly. This would provide more power pulses per revolution at the same periodicity provided there is a symmetrical offsetting or staggering of the blades 123 on each tier or blade assembly. In the example in which the VWAT deployed 3 tiers or stacked coupled blade assemblies and 3 blades 123 are deployed on each tier, the first blade 123 would have an absolute angular references about the tower axis of zero degrees, with the other 2 blades on the same tier would be set at 120 and 240 degrees (for a spacing of 360/number of blades). Whereas on the upper or second tier the blades would at an angular reference position or offset of 40, 160 and 280 degrees, as well as an angular offset on 80, 200 and 220 degrees on the third tier of blades. Note that the annular offset between each tier is the spacing within the tier (120 degrees), divided by the number of tiers. It should now be appreciated that other variations of spacing and different numbers of tiers are both possible and practical.
A cellular communication tower is adapted to support a vertical axis wind turbine (VAWT) that includes a generator mechanism. The signal and power cable for the communication antennas run through the central axis or bore of the generator. The blades of the VAWT are disposed so as to avoid interferences with communication signals. The tower preferably deploys an open truss construction to avoid the impact of periodic pressure pulse as the turning blades shift out of alignment from shading the tower. Thus, with an open truss tower the turbine blades can be a larger size and still not cause such pressure pulses.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] The present application claims the benefit of priority to the U.S. provisional application of the same title having application Ser.", "No. 61/287,635, which was filed on Dec. 17, 2009, which is incorporated herein by reference.", "BACKGROUND OF INVENTION [0002] The present invention relates to the provision of energy to wireless telecommunications systems, and in particular to such provision by wind powered generators, as well as to the generation of electrical power from wind energy.", "[0003] Wireless telecommunications technology is especially attractive to remote communities lacking an existing signal wire system, and in particular to developing countries that have no or minimal telecommunications outside of major cities.", "[0004] However, while cellular wireless telecommunication is well advanced, the locations most lacking in these services also frequently lack connection to a reliable electrical power distribution infrastructure to provide power to the electronic systems, such as the radio frequency and microwave transceivers, deployed on cellular telecommunication transmission towers.", "[0005] It is therefore a first object of the present invention to provide a means for powering the electronics systems deployed on remote cellular telecommunication transmission towers as well as provide a reliable power source for remote cell communication towers [0006] It is a further object of the invention to reduce the installed cost of generating electrical power by taking advantage of telecommunication infrastructure.", "SUMMARY OF INVENTION [0007] In the present invention, the first object is achieved by providing a tower structure comprising, a substantially vertical support tower having a top portion and a lower mounting base and at least a portion with a central vertical lumen or opening therein between the top portion and the lower mounting base thereof, a vertically arrayed wind turbine (VAWT), having a central mounting hub and a plurality of turbine blades coupled thereto to provide free rotation about the central opening of said substantially vertical support tower, an electrical generator rotationally coupled to said central mounting hub, at least one of a receiver, transmitter or transceiver of electromagnetic radiation supported by said a substantially vertical support tower and disposed above said VAWT, at least one cable for power transmission extending downward from the generator, being electrically coupled thereto to the lower mounting base, and at least one cable extending upward from the lower mounting base through the central mounting hub of the VAWT to connect in signal communication with said at least one of an receiver, transmitter or transceiver.", "[0008] The above and other objects, effects, features, and advantages of the present invention will become more apparent from the following description of the embodiments thereof taken in conjunction with the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIG. 1 is a perspective view of a first embodiment of the invention.", "[0010] FIG. 2 is a perspective view of a second embodiment of the invention.", "[0011] FIG. 3 is a perspective view of a second embodiment of the invention.", "[0012] FIGS. 4A and B is a plan view of section A-A of FIG. 1 illustrating alternative positions of the antenna blades [0013] FIG. 5 is cross-section elevation of a portion of the embodiment shown in FIG. 1-3 .", "[0014] FIG. 6 is cross-section elevation of a third embodiment of the invention.", "[0015] FIG. 7 is cross-section elevation of a fourth embodiment of the invention.", "[0016] FIG. 8 is a plan section view of a portion of the tower and generator/alternator showing a preferred method of assembly, whereas FIG. 8B is a cross-sectional elevation thereof.", "DETAILED DESCRIPTION [0017] Referring to FIGS. 1 through 8 , wherein like reference numerals refer to like components in the various views, there is illustrated therein a new and improved antenna mounted wind power generator, generally denominated 100 herein.", "[0018] In accordance with the present invention, FIG. 1 illustrates a first embodiment of the antenna mounted wind power generator 100 that comprises an antenna assembly 105 , consisting of generally conventional antenna devices, in this case panel type transceivers 140 of electromagnetic radiation that transmit and receive encoded RF or microwave signal information.", "This antenna assembly 105 is mounted at the top of the antenna support tower 110 and disposed above the vertically arrayed wind turbine (VAWT) 120 .", "In this embodiment the antenna support tower 110 is a tubular tower, having a generally circular cross-section.", "At least a portion of the antenna support tower 110 below the antenna assembly 105 has a lumen or central vertical opening 111 , although it appears solid on the outside.", "The VAWT 120 is mounted on the antenna support tower 110 below the antenna assembly 105 , being disposed for free rotation about the central opening 111 via at least one pairs of two hubs 121 and 121 ′ that are coupled to the antenna support tower 110 .", "Since this particular VAWT 120 has a pair of coupled blade assemblies 125 and 126 stacked on each other there are 2 hubs, 121 being disposed at the top of the upper blade assembly 125 and 121 ′ being disposed at the bottom of the lower blade assembly 126 .", "Radial struts 124 extend outward from each hub 121 and connect to horizontally disposed blade support rings 122 , 122 ′ and 122 ″′.", "The blades 123 are vertically disposed and connect to each blade assembly 125 and 126 by the blade support rings 122 and 122 ′ or 122 ′ and 122 ″, at their top and bottom Thus, each of the blade assemblies 125 and 126 has in common the centrally disposed of the three blade support rings 122 ′, which is not connected to the antenna support tower 105 directly.", "The generator 130 is preferably disposed below hub 121 so that its rotor 132 can be connected to the rotating outer portion of the lower hub 121 that is driven by wind induced rotation of the rings supports 122 by the force acting on the turbine blades 123 .", "A preferred VWAT architecture is described in US Pat. Appl.", "no. US 2008/0253889 A1, of Krivcov et al.", "that published on Oct. 16, 2008 for a VERTICAL AXIS WIND TURBINES, which is incorporated herein by reference.", "[0019] Alternative designs for VWAT are also disclosed in U.S. Pat. No. 7,329,965 B2 issued to Roberts et al.", "on Feb. 12, 2008 for an AERODYNAMIC-HYBRID VERTICAL-AXIS WIND TURBINE, which is also incorporated herein by reference.", "It is not intended that the invention be limited to any particular form of a VAWT.", "[0020] As the portion of the tower 110 that support the VAWT 120 cannot interfere with the hub rotation, the signal cables 160 that connects a base station 520 to the RF or microwave transceiver 140 runs through the lumen or central vertical opening 111 , as shown in FIG. 5 .", "The power cable(s) 150 emanate from the generator 130 can run down either the outside of the tower 110 or through the portion of the central opening 111 that extends below the vertical expanse of the VAWT 120 .", "[0021] Generally speaking VAWT's have particular advantages as compared to deploying horizontal axis wind turbines.", "This is particularly true for the inventive combination with the antenna system 105 at the top of the tower.", "The VWAT blades 123 , being oriented in the same direction of the tower 110 are below the antenna 140 and will not shadow or block them in a manner that would attenuate signals.", "[0022] Further, because the centers of gravity of the VWAT 120 and generator 130 align are both disposed on the central or primary vertical axis of the on the antenna tower 110 , the structural demands of the antenna tower 110 are not expected to be significantly greater than they would be for just the antenna assembly 105 .", "As a mounting tower is a significant part of the cost of any wind turbine system, using cellular telephone transmission towers reduces the cost to supply electrical power with a wind turbine, which can power the antenna or serve other users in the area.", "[0023] Further as the preferred embodiment of the VWAT is efficient at generating power in light winds from any direction, the antenna mounted wind generator system is practical and useful to deploy in most locations where the antennas would be sited for communication purposes only.", "The ability to generate power in light winds from any direction favors using the VWAT generated power to energize the antenna system itself as described further below, as it is more likely that power will be available when needed.", "However, to the extent there is not always the minimum wind necessary to generate power, back up batteries, or any other energy storage medium for such occasions could at least be of are reduced size to accommodate the rare occasions where there would not be sufficient wind to turn the VWAT.", "[0024] Further, as VWAT's 120 have lower tip speed of the turbine blades that rotate in a vertical plane about a horizontal shaft they tend to minimize the potential for bird kill.", "[0025] In the embodiment shown in FIG. 1 , the antenna support tower 110 is an elongated tube of generally circular cross-structure.", "[0026] In the embodiment shown in FIG. 2 the antenna support tower 110 has an open truss framed tower from the ground until the antenna portion 105 .", "[0027] In the embodiment shown in FIG. 3 the antenna support tower 110 is an elongated tube of generally circular cross-structure in the lower portion 110 a between the ground and the generator 130 , which is situated just below hub 121 to couple to the rotor 132 ( FIG. 5 ).", "However, the central portion 110 b of the tower 110 that runs through the VWAT 120 is of a truss type framed construction.", "One non-limiting example of such a frame construction is illustrated as composed of vertically spaced apart rings held at their outer periphery by a plurality of vertical posts.", "[0028] FIGS. 4A and 4B illustrate why the embodiment of FIG. 2 is more preferred over that in FIG. 1 .", "In these figures the wind is coming from the left as indicated by the array of arrows 200 .", "Each turbine blade 123 creates a lower pressure “shadow”", "210 in the region behind it with respect to the wind direction and blade shape.", "In FIG. 4A , the shadows 210 do not cross the cross-section of the antenna tower inside hub 121 , hence the antenna is subjected to the force of the wind 200 .", "However, in FIG. 4B , as the blades 123 have rotated with support ring 122 , a blade now casts a lower pressure “shadow”", "that includes the tower 110 .", "Thus, with a solid tower, due to its wider cross-section, will be subject to a periodic variation in stress as the VWAT rotates, coming in and out of the shadow 210 .", "However, if the section of the tower 110 b within the central axis of the VWAT's rotation is generally open constructed from struts, rings or trusses, the pressure variation will be lower although the same “shading”", "will still occur, as the such constructions present a much small cross-section when not “shaded”", "in FIG. 4A .", "[0029] Thus, FIG. 2 and FIG. 3 are more preferred embodiments because they minimize such periodic stress and potential for movement to the antenna 105 .", "Where a solid tower cross-section is preferred at a least the ground level, the embodiment of FIG. 3 is more preferred as the strut or frame is only visible far from the ground away for the height of the VWAT 120 .", "[0030] FIG. 5 illustrates in more detail an embodiment for coupling the rotating portion of the hub 121 , to the rotor 131 of generator 130 .", "The hub 121 that supports the VWAT blades 123 is connected in rotary engagement with the tower 110 by the bearing plate 501 .", "FIG. 5 also illustrates an additional embodiment in which the power generated by the VWAT, via generator 130 , is transmitted via cable 150 to a battery 510 .", "The battery 510 optionally powers the base electronic system or unit 520 that is connected to the signal cable 160 .", "The signal cables 160 convey signal and routing information to the base electronic system for routing to different antennas or land based telecommunication cables.", "The base electronic signal system need not be located at ground level, and it components can be disturbed in different location with respect to the antenna assembly 105 .", "Thus, antennas or transceivers 140 are optionally self-powered by the VWAT 120 , or powered by the VWAT 120 via a battery 510 , when either normal (land base power) or wind power is not available due to insufficient breezes.", "[0031] It should be appreciated that the various embodiment described above have the benefits of reducing the installed cost of generating electrical power by taking advantage of telecommunication infrastructure, that is the necessity of having erected plural remote towers for cellular phone communications.", "Thus the power generated by VWAT 120 can be used by local users or feed back into the power grid.", "[0032] VWAT's of the preferred design has several advantages for recharging the batteries of a cell phone base station, or generating electricity in general.", "As the cell phone towers are likely to be situated by reception criteria, and not specifically to take advantage of locations with steady high wind conditions, the VWAT design is particularly advantageous because it is self starting in low wind conditions.", "Further, the performance of the VWAT does not depend on the wind direction, in that is omni-directional.", "Not only does the generator's 130 electrical output not depend on the compass heading of the wind, it also doesn't matter how rapidly it changes direction.", "Thus, the preferred VWAT turbine still captures wind energy as the wind changes direction, which that is continuously converted to electrical power.", "Further, the VAWT mass acts as a flywheel, picking up some speed in wind gusts and continuing to rotate in the short periods of low wind.", "Accordingly, a VWAT of the preferred design can be constantly charging the back-up battery or generating power in a wider range of cell tower location.", "Unlike Horizontal Axis Wind Turbine (HAWT), there is no requirement for the windmill to “seek”", "the wind direction.", "Accordingly another advantage of the invention is the elimination of the expensive and unreliable mechanics related to pointing an HWAT toward the wind.", "Thus, a VWAT will have a smooth, steady, quiet motion eliminating noise, and reducing energy losses of starting and stopping.", "Vibrations in the mounting structure are also reduced, while the flywheel effect gives a more constant voltage output to the electronics.", "Accordingly, the various embodiment of the invention will provide a reliable power source for remote cell communication towers and other users or consumers of power.", "[0033] It is also expected that the preferred embodiments will not cause interference with RF transmission, as well as provide for easier maintenance to the generator, such as replacing bearings, without the need to depower or terminate RF transmission.", "[0034] In furtherance of another objective of facilitating maintenance of the RF transmission system 105 , FIG. 6 illustrates a more preferred embodiment in which a tower 110 is hollow and can be entered at or near the ground 1 via a lower access door 601 via portal 611 that allows maintenance personnel 10 to enter and climb up the internal ladder 602 , exiting an upper access door 603 at portal 613 , thus leading them to the panel type transceivers 140 and connecting signal cables 160 that also runs through tower 110 .", "The ladder 602 can be a series of spaced apart vertical rungs, without the connecting extending horizontal side bars, or any other structure or apparatus that permits self propelled or automated transportation of the maintenance personnel 10 above the VWAT 120 to access the antenna supporting portion of the tower.", "As shown in this figure, it may be preferable that the tower 120 is a hollow tube below upper access door 603 , but of strut or truss construction above it.", "[0035] FIG. 7 illustrates an alternative and more preferred embodiment in which the tower 110 is solid but internally hollow to provide access via the internal ladder 602 as in FIG. 6 , however, the exit portal 613 and upper access door 603 are now located below the VWAT 120 , in the lower portion 110 a , such that the upper portion 110 c of the tower 110 below the antenna system 105 , including the panel type transceivers 140 , is of a hollow strut or truss construction structure through which the ladder 602 optionally extends providing access to transceivers 140 while the VWAT 120 rotates.", "Depending on the strut or truss spacing the ladder need not be a continuous unitary structure, but can be additional foot and handhold members spaced apart the conventional distance of about a foot (about 30 cm), which may include some strut or truss members themselves.", "[0036] FIG. 8A schematically illustrates in a plan view of a preferred embodiment in which portions of the generator are assembled from arc shaped segments that surround the hollow tower 110 .", "FIG. 8B is a cross-sectional elevation of the same region.", "The stator 131 is formed from a plurality of arc shaped stator segments 8131 that are attached to a flange or hub 121 ′ that is coupled to the tower 110 to provide the stationary portion of the generator 130 .", "The rotor 132 is formed from a plurality of arc shaped rotor segments 8132 that are attached to a flange or hub 121 that is coupled to tower 110 by rotary bearings to form one or more rotor assemblies 131 .", "One or within each rotor segment 8132 are a plurality of wedge shaped magnets 8032 that alternatively in polarity to provide along with the stator 131 , an axial gap electric dynamo type generator/alternator.", "In the more preferred embodiment of FIG. 8B , each arc shaped segment 8131 that will form the stator disc 131 has connected serpentine wiring 8031 loops on both sides and is inserted sideways over the rotor disc 132 .", "The serpentine winding in such a disc is disclosed in U.S. Pat. No. 7,646,132 B2, issued to R. Halstead on Jan. 12, 2010, which is incorporated herein by reference.", "It should also be appreciated that such arc shaped rotor and stator segment can be pre-assembled into arc shaped units which are then mounted on the appropriate hub structure on the periphery of the tower 110 .", "Further, one the arc shaped segment of the rotor and stator are coupled to the tower via a hub they can be mechanically coupled to each other for greater stability.", "[0037] It is also preferred that a magnetic bearing be deployed at the outer extremity or perimeter of the rotor disk 132 , such as that disclosed in the US Pat. Application No. used at the perimeter of the rotor disk 132 , as disclosed in US Patent Publication No. 2009-200883A1, published on Aug. 13, 2009, which is incorporated herein by reference.", "Such a magnetic bearing assembly can also be assembled in arc shaped segment as described above.", "[0038] While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be within the spirit and scope of the invention as defined by the appended claims.", "[0039] For example, the VAWT 120 of antenna assembly 100 may deploy additional pairs of stacked coupled blade assemblies than the two ( 125 and 126 ) shown in FIG. 1-3 , as for example 3 to 4 blade assemblies.", "In addition, more than 3 individual blades or air foils 123 can be deployed in the 2 or more blades assemblies, as for example 3-5 blades per stacked blade assembly.", "This would provide more power pulses per revolution at the same periodicity provided there is a symmetrical offsetting or staggering of the blades 123 on each tier or blade assembly.", "In the example in which the VWAT deployed 3 tiers or stacked coupled blade assemblies and 3 blades 123 are deployed on each tier, the first blade 123 would have an absolute angular references about the tower axis of zero degrees, with the other 2 blades on the same tier would be set at 120 and 240 degrees (for a spacing of 360/number of blades).", "Whereas on the upper or second tier the blades would at an angular reference position or offset of 40, 160 and 280 degrees, as well as an angular offset on 80, 200 and 220 degrees on the third tier of blades.", "Note that the annular offset between each tier is the spacing within the tier (120 degrees), divided by the number of tiers.", "It should now be appreciated that other variations of spacing and different numbers of tiers are both possible and practical." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of co-pending application Ser. No. 09/917,857, filed on Jul. 31, 2001, which is a continuation-in-part of application Ser. No. 09/761,108, filed on Jan. 17, 2001, the entire contents of which are hereby incorporated by reference. BACKGROUND [0002] 1. Filed of the Invention [0003] The present invention is generally directed to a multi-angle hook and an L-shaped hinge and more particularly, to a multi-angle hook and an L-shaped hinge for use with a furniture extension. [0004] 2. Description of the Related Art [0005] Futon frames come in one of at least two different configurations, bi-fold, and tri-fold. In a bi-fold configuration illustrated in FIG. 1, a convertible futon sofa-bed frame allows the futon mattress to fold once along its length. Typically, bi-fold configurations are utilized for larger width furniture, such as sofas, so that one or more persons may lie on the futon sofa-bed frame, with the orientation illustrated in FIG. 2. [0006] The tri-fold configuration, illustrated in FIG. 3, is more commonly utilized for narrower futon frames (for example a 28″ wide chair or 54″ wide loveseat). In a tri-fold, the futon mattress is folded twice along its usually shorter width. A futon mattress may hang over the back of the frame or be folded under the seat itself, or lay flat as a chaise lounge style seat. A person lies on the tri-fold in the orientation illustrated in FIG. 4. [0007] An extension 10 may be added to the seat platform 12 of a futon frame to form a leg-rest (as an ottoman) as well as giving extra length to smaller size futon frames to allow the user to form the full length bed illustrated in FIG. 4. [0008] The extension 10 may be a framed platform including outer frame members and inside slat components. The slats of the extension 10 commonly “nest” into the slats of the seat platform 12 ; in other words, the extension slats slide in between the slats of the seat platform 12 , sliding in and out in relation to them. [0009] The extension 10 may be fastened to the seat in various ways but most commonly there is a bar of wood or metal on the underside of (and at the rear of) the extension slats which holds the extension slats together as fixed group. This bar also serves to stop the extension 10 from being pulled completely out of the seat platform 12 . The bar is below the slats and stops firmly against the frame of the seat platform 12 keeping the extension 10 from pulling out completely. This bar is permanently fixed to the extension 10 and makes removal of the extension 10 from the rest of the frame impossible. SUMMARY OF THE INVENTION [0010] The present invention changes the nature of the attachment of the extension to the seat platform by allowing easy and complete removal of the extension from the seat platform. [0011] The present invention utilizes a multi-angle hook that allows the extension platform to be freely lifted off the seat platform and alternately lowered and set into place. [0012] This flexibility is advantageous in the following ways: [0013] 1) conversion of the futon frame into its various positions (bed, recliner, and upright-sofa) is easier to do as the frame is easier to manipulate with the extension removed; [0014] 2) defective parts are easily replaced; and/or [0015] 3) parts management in manufacturing is simpler thereby saving production cost. [0016] Additionally, the multi-angle hook is stepped at its holding points to allow for at least two positions most extensions require: [0017] 1) Horizontal: flat for straight-legged position, such as a bed position; and [0018] 2) angled to the floor: a “steamer” position. [0019] Further, the present invention allows the seat platform to not include side rails. The present invention utilizes an L-shaped hinge, attachable to the seat platform, for securing the side rail-less seat platform to a back platform. BRIEF DESCRIPTION OF THE DRAWINGS [0020] [0020]FIG. 1 illustrates a conventional bi-fold configuration. [0021] [0021]FIG. 2 illustrates the typical orientation of person(s) lying on a bi-fold futon bed-frame. [0022] [0022]FIG. 3 illustrates a conventional tri-fold configuration. [0023] [0023]FIG. 4 illustrates the typical orientation of a person lying on a tri-fold futon bed-frame. [0024] [0024]FIGS. 5 a - 5 d illustrate the multi-angle hook in one exemplary embodiment of the present invention. [0025] [0025]FIGS. 6 a - 6 d illustrate the relationship between the extension, the seat platform, and the multi-angle hook of the present invention in several exemplary positions. [0026] [0026]FIGS. 7 a - 7 c illustrate the lounger position, the steamer position, and the bed position, respectively, from additional angles. [0027] [0027]FIG. 8 illustrates a seat platform and an L-shaped hinge in one exemplary embodiment of the present invention. [0028] [0028]FIGS. 9 a - 9 d illustrate the L-shaped hinge in an assembled futon frame, from various angles, in one exemplary embodiment of the present invention. [0029] [0029]FIGS. 10 a - 10 d illustrate the L-shaped hinge from various perspectives and FIGS. 10 e - 10 f illustrates a securing device for securing the L-shaped hinge to a frame component in one exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0030] [0030]FIGS. 5 a - 5 d illustrate the multi-angle hook 20 in one exemplary embodiment of the present invention. FIG. 5 a illustrates a side view, FIG. 5 b a front view, FIG. 5 c a foldout view, and FIG. 5 d an additional view. As illustrated in FIG. 5 a , the multi-angle hook 20 includes a member 22 and a member 24 , which, as shown, are at a right angle or substantially a right angle to each other, although this is not essential. In fact, the angle between members 22 and 24 can be any angle as long as the angle is capable of a portion of the seat platform 12 , which will be discussed in more detail below with respect to FIGS. 6 a - 6 d . The multi-angle hook 20 also includes a member 26 and a member 28 . In a preferred embodiment, the multi-angle hook 20 is formed as a single piece, preferably of metal, but also possibly of any type of rigid, sturdy, plastic, wood or any other suitable material. As illustrated in FIGS. 5 a and 5 d , the angle between members 22 and 24 is obtuse, in particular, approximately 135° and the angle between members 26 and 28 is a right angle or substantially a right angle to each other, although these values are also not essential. In fact, similar to the angle between members 22 and 24 , the angles between members 24 and 26 and members 26 and 28 can be any angle as long as the angles are capable of catching a portion of the seat platform 12 , which will be discussed in more detail below with respect to FIGS. 6 a - 6 d. [0031] As illustrated in FIGS. 5 a - 5 d , the multi-angle hook 20 includes at least one hole 30 for securing the multi-angle hook to the extension 10 . In a preferred embodiment, the at least one hole 30 is counter-sunk. In another preferred embodiment, the number of holes 30 is three, although any number of holes may be used. Further, the manner in which the multi-angle hook 20 is secured to the extension 10 , such as, screws, bolts, nails, rivets, pins, staples, snaps, (or any other suitable fastener), glue (which might obviate the need for holes altogether), etc., is not significant, as long as the multi-angle hook 20 and the extension 10 are secured together. [0032] [0032]FIGS. 6 a - 6 d illustrate the relationship between the extension 10 , the seat platform 12 , and the multi-angle hook 20 in several positions. FIG. 6 a illustrates the bed position, where the extension 10 and the seat platform 12 are both substantially parallel to the floor. As illustrated in FIG. 6 a , the multi-angle hook 20 is secured to the extension 10 and the multi-angle hook 20 is arranged such that it catches the seat platform 12 . As illustrated, member 22 of the multi-angle hook 20 contacts and is substantially parallel to a top side of the seat platform 12 and member 24 of the multi-angle hook 20 contacts and is substantially parallel to a front side of the seat platform 12 . In this manner, the extension 10 is supported by the seat platform 12 at one end and via legs 11 at the other end. Further, the multi-angle hook 20 enables the extension to temporarily engage the seat platform 12 , when in the bed position. [0033] [0033]FIG. 6 b illustrates the steamer position, where the extension 10 and the seat platform 12 are both substantially tilted with respect to the floor. As illustrated in FIG. 6 b , the multi-angle hook 20 is secured to the extension 10 and the multi-angle hook 20 is arranged such that it again catches the seat platform 12 . As illustrated, member 26 of the multi-angle hook 20 contacts and is substantially parallel to a top side of the seat platform 12 and member 28 of the multi-angle hook 20 contacts and is substantially parallel to a front side of the seat platform 12 . In this manner, the extension 10 is supported by the seat platform 12 at one end and via the floor on the other end. Further, the multi-angle hook 20 enables the extension to temporarily engage the seat platform 12 , when in the steamer position. It may also be advantageous for member 22 to have a notch or indent 21 , at one end to further secure the seat platform 12 . It is further noted that member 28 is optional [0034] [0034]FIG. 6 c illustrates the lounger position, which is somewhat of a hybrid between the bed position and the steamer position in that the extension 10 may be parallel or substantially parallel to the floor as in the bed position (although the seat platform 12 is not) or the extension 10 may be tilted with respect to the floor, but less tilted than the seat platform 12 in the steamer position. As illustrated in FIG. 6 c , the multi-angle hook 20 is secured to the extension 10 and the multi-angle hook 20 is arranged such that it again catches the seat platform 12 . As illustrated, member 24 of the multi-angle hook 20 contacts the side of the seat platform 12 and member 22 and/or the extension 10 itself contact the top side of the seat platform 12 . In this manner, the extension 10 is supported by the seat platform 12 at one end and via the legs 11 on the other end. Further, the multi-angle hook 20 enables the extension to temporarily engage the seat platform 12 , when in the lounger position. It may also be advantageous for member 24 and/or member 22 (or the extension 10 itself) to have a notch or indent 21 , to further secure the seat platform 12 . [0035] [0035]FIG. 6 d illustrates the closed or unextended position, where the slats of the extension 10 are nested within the slats of the seat platform 12 . The extension slats slide in between the slats of the seat platform 12 , sliding in and out in relation to them. As illustrated in FIG. 6 d , the extension 10 and the seat platform 12 are both substantially tilted with respect to the floor. As illustrated in FIG. 6 d , the multi-angle hook 20 is arranged in front of a rear rail of the seat platform 12 . As illustrated in FIG. 6 d , there is little or no interaction between the multi-angle hook and the seat platform 12 in the closed or unextended position. [0036] [0036]FIGS. 7 a - 7 c illustrate the lounger position, the steamer position, and the bed position, respectively, from additional angles. [0037] In order to facilitate the attachment of the legs 11 of the extension 10 to the extension 10 itself, it may be advantageous to eliminate side rails from the seat platform 12 . As illustrated in FIG. 6 a , the extension 10 includes side rails (as does the back platform 13 ), but the seat platform 12 does not. This arrangement allows easy and secure attachment of the legs 11 to the extension 10 . [0038] Further, hinging of the seat platform 12 and the back platform 13 may be better achieved by not utilizing the conventional futon frame pivot connection. The conventional connection for futon frames is a clevis pin passing through a hole on the back platform side rail 13 ′ and again through a hole in the seat platform side rail thereby coupling the two platforms together. Without a seat platform side rail to connect to, the clevis pin passing through the back platform side rail 13 ′ has only the end of the seat long rail to be inserted into. The stress on a wood rail, created in this manner, may be excessive and could subject the seat long rail to cracking along the wood grain. [0039] [0039]FIG. 8 illustrates a solution to this problem, namely an L-shaped hinge attachable to the seat platform 12 for the purpose of coupling the seat platform 12 and the back platform 13 together, allowing the seat platform 12 and the back platform 13 to pivot freely and securely in relation to each other. As illustrated in FIG. 8, the seat platform 12 includes a rear long rail 80 , a front long rail 81 , slats 82 , and no side rails. The L-shaped hinge 90 gives the required support to the end of the rear long rail 80 , when secured to the back platform side rail 13 ′ of FIG. 6 a. [0040] The seat platform 12 is coupled to the back platform 13 by inserting a clevis pin 100 through a hole in the back platform side rail 13 ′ and into the seat rear long rail 80 , first passing through the L-shaped hinge 90 , which is securely attached to the seat rear long rail 80 . [0041] With the clevis pin 100 fully inserted as described, the clevis pin 100 is then locked into place with a conventional locking pin. The locking pin is fit through one of one or more holes ( 102 shown in FIGS. 10 e - 10 f ) in and through (substantially perpendicular to) the far tip (away from the head) of the clevis pin 100 . [0042] To allow access by the locking pin to the hole at the far tip of the clevis pin 100 while the clevis pin 100 is fully inserted into the seat rear long rail 80 , an access hole 101 is provided in and through (substantially perpendicular to) the surface of the seat rear long rail 80 . The relationship between the seat rear long rail 80 , the L-shaped hinge 90 , and the access hole 101 is further illustrated in FIGS. 9 a - 9 d. [0043] [0043]FIGS. 10 a - 10 f illustrate an exemplary L-shaped hinge 90 and associated clevis pin 100 , in more detail. FIGS. 10 a , 10 b , 10 c , and 10 d illustrate top, isometric, front, and outside views, respectively, of the L-shaped hinge 90 . The L-shaped hinge 90 includes at least two flanges 92 , 94 , which form around the end of the seat rear long rail 80 . The flanges 92 , 94 include one more holes 91 to secure the L-shaped hinge 90 to the seat rear long rail 80 . The holes 91 may be countersunk. The flange 94 also includes a hole 93 for the clevis pin 100 . As most clearly illustrated in FIG. 10 b , the hole 93 is not countersunk, and in fact, may extend outwardly. FIGS. 10 e - 10 f illustrate top and isometric views, respectively of the holes 102 of the clevis pin 100 , in more detail. [0044] As illustrated in FIG. 10 e - 10 f , to allow easy insertion of the locking pin into the clevis pin 100 , the clevis pin 100 includes holes 102 , in substantially the same transverse plane, but approximately 90° apart. The holes 102 allows easy access for the locking pin to a hole in the clevis pin 100 , regardless of the clevis pin's random rotation in the seat rear long rail 80 . [0045] Although each of FIGS. 6 a - 6 d and 7 a - 7 c illustrate two multi-angle hooks, any number of hooks 20 may be utilized. Further, although the multi-angle hook 20 of FIGS. 6 a - 6 d and 7 a - 7 c contacts top and front sides of the front rail of the seat platform 12 , the multi-angle hook 20 may contact any surface of the seat platform 12 or the extension 10 to accomplish the desired goal. Still further, although the multi-angle hook 20 of FIGS. 6 a - 6 d and 7 a - 7 c is shown as being attached to the extension 10 , the multi-angle hook could also be attached to the seat platform 12 . Still further, the multi-angle hook 20 may be configured so that in the lounger position, the extension 10 is inclined with respect to the floor (FIG. 6 c ) or parallel to the floor (FIG. 7 a ). [0046] It is obvious from FIGS. 6 a and 6 c that member 28 is unnecessary in both the bed and lounger positions. It is less obvious that member 28 is also not necessary (although helpful) in the steamer position of FIG. 6 b . The weight of the futon mattress can keep the multi-angle hook 20 in place in the steamer position. Accordingly, the inclusion of member 28 is considered desirable, but not necessary. [0047] As described the present invention is directed to a multi-angle hook and a method of temporarily securing two frame components of a futon bed together. The multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention changes the nature of the attachment two frame components of a futon bed by allowing easy and complete removal of one frame component from another. The multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention allow one frame component to be freely lifted off another frame component and alternately lowered and set into place. [0048] The multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention facilitates conversion of the futon frame into its various positions (bed, steamer, lounger) because the futon frame is easier to manipulate with one of the frame components removed. Further, defective parts are easily replaced using the multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention. Still further, parts management in manufacturing is simpler using the multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention, thereby saving production cost. [0049] In a preferred embodiment, the L-shaped hinge 90 is formed as a single piece, preferably of metal, but also possibly of any type of rigid, sturdy, plastic, wood or any other suitable material. [0050] In a preferred embodiment, the at least one hole 91 is counter-sunk. In another preferred embodiment, the number of holes 91 is four, although any number of holes may be used. Further, the manner in which the L-shaped hinge 90 is secured to the back platform 12 , such as, screws, bolts, nails, rivets, pins other than clevis pins, staples, snaps, (or any other suitable fastener), glue (which might obviate the need for holes altogether), etc., is not significant, as long as the L-shaped hinge 90 and the back platform 12 are secured together. [0051] It is further noted that, although in the embodiments described above, the seat platform 12 does not include side rails, it may be the back platform 13 or extension 10 (or any combination thereof) which does include side rails. [0052] It is further noted that the hinge need not be L-shaped or even substantially L-shaped, but merely of a shape to substantially conform to the end of the seat platform 12 , back platform 13 or extension 10 . [0053] As described the present invention is directed an L-shaped hinge and a method of temporarily securing two frame components of a futon bed together. [0054] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
A multi-angle hook fastened to an extension member, that is used to stop the extension from completely pulling out of the frame it sits in. When fully extended, the multi-angle hook allows at least three different holding positions, seen as three different angles that the extension sits at while using the multi-angle hook as its fixed point of pivot. The multi-angle hook is a metal, plastic, or wood plate bent along several parallel lines, across its width, at varying angles. An L-shaped hinge which is used to secure a side rail-less frame member to another frame member, to avoid undue stress on the side rail-less frame member. The L-shaped hinge is a metal, plastic, or wood plate which substantially conforms to a portion of a side rail-less frame member.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of co-pending application Ser.", "No. 09/917,857, filed on Jul. 31, 2001, which is a continuation-in-part of application Ser.", "No. 09/761,108, filed on Jan. 17, 2001, the entire contents of which are hereby incorporated by reference.", "BACKGROUND [0002] 1.", "Filed of the Invention [0003] The present invention is generally directed to a multi-angle hook and an L-shaped hinge and more particularly, to a multi-angle hook and an L-shaped hinge for use with a furniture extension.", "[0004] 2.", "Description of the Related Art [0005] Futon frames come in one of at least two different configurations, bi-fold, and tri-fold.", "In a bi-fold configuration illustrated in FIG. 1, a convertible futon sofa-bed frame allows the futon mattress to fold once along its length.", "Typically, bi-fold configurations are utilized for larger width furniture, such as sofas, so that one or more persons may lie on the futon sofa-bed frame, with the orientation illustrated in FIG. 2. [0006] The tri-fold configuration, illustrated in FIG. 3, is more commonly utilized for narrower futon frames (for example a 28″ wide chair or 54″ wide loveseat).", "In a tri-fold, the futon mattress is folded twice along its usually shorter width.", "A futon mattress may hang over the back of the frame or be folded under the seat itself, or lay flat as a chaise lounge style seat.", "A person lies on the tri-fold in the orientation illustrated in FIG. 4. [0007] An extension 10 may be added to the seat platform 12 of a futon frame to form a leg-rest (as an ottoman) as well as giving extra length to smaller size futon frames to allow the user to form the full length bed illustrated in FIG. 4. [0008] The extension 10 may be a framed platform including outer frame members and inside slat components.", "The slats of the extension 10 commonly “nest”", "into the slats of the seat platform 12 ;", "in other words, the extension slats slide in between the slats of the seat platform 12 , sliding in and out in relation to them.", "[0009] The extension 10 may be fastened to the seat in various ways but most commonly there is a bar of wood or metal on the underside of (and at the rear of) the extension slats which holds the extension slats together as fixed group.", "This bar also serves to stop the extension 10 from being pulled completely out of the seat platform 12 .", "The bar is below the slats and stops firmly against the frame of the seat platform 12 keeping the extension 10 from pulling out completely.", "This bar is permanently fixed to the extension 10 and makes removal of the extension 10 from the rest of the frame impossible.", "SUMMARY OF THE INVENTION [0010] The present invention changes the nature of the attachment of the extension to the seat platform by allowing easy and complete removal of the extension from the seat platform.", "[0011] The present invention utilizes a multi-angle hook that allows the extension platform to be freely lifted off the seat platform and alternately lowered and set into place.", "[0012] This flexibility is advantageous in the following ways: [0013] 1) conversion of the futon frame into its various positions (bed, recliner, and upright-sofa) is easier to do as the frame is easier to manipulate with the extension removed;", "[0014] 2) defective parts are easily replaced;", "and/or [0015] 3) parts management in manufacturing is simpler thereby saving production cost.", "[0016] Additionally, the multi-angle hook is stepped at its holding points to allow for at least two positions most extensions require: [0017] 1) Horizontal: flat for straight-legged position, such as a bed position;", "and [0018] 2) angled to the floor: a “steamer”", "position.", "[0019] Further, the present invention allows the seat platform to not include side rails.", "The present invention utilizes an L-shaped hinge, attachable to the seat platform, for securing the side rail-less seat platform to a back platform.", "BRIEF DESCRIPTION OF THE DRAWINGS [0020] [0020 ]FIG. 1 illustrates a conventional bi-fold configuration.", "[0021] [0021 ]FIG. 2 illustrates the typical orientation of person(s) lying on a bi-fold futon bed-frame.", "[0022] [0022 ]FIG. 3 illustrates a conventional tri-fold configuration.", "[0023] [0023 ]FIG. 4 illustrates the typical orientation of a person lying on a tri-fold futon bed-frame.", "[0024] [0024 ]FIGS. 5 a - 5 d illustrate the multi-angle hook in one exemplary embodiment of the present invention.", "[0025] [0025 ]FIGS. 6 a - 6 d illustrate the relationship between the extension, the seat platform, and the multi-angle hook of the present invention in several exemplary positions.", "[0026] [0026 ]FIGS. 7 a - 7 c illustrate the lounger position, the steamer position, and the bed position, respectively, from additional angles.", "[0027] [0027 ]FIG. 8 illustrates a seat platform and an L-shaped hinge in one exemplary embodiment of the present invention.", "[0028] [0028 ]FIGS. 9 a - 9 d illustrate the L-shaped hinge in an assembled futon frame, from various angles, in one exemplary embodiment of the present invention.", "[0029] [0029 ]FIGS. 10 a - 10 d illustrate the L-shaped hinge from various perspectives and FIGS. 10 e - 10 f illustrates a securing device for securing the L-shaped hinge to a frame component in one exemplary embodiment of the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0030] [0030 ]FIGS. 5 a - 5 d illustrate the multi-angle hook 20 in one exemplary embodiment of the present invention.", "FIG. 5 a illustrates a side view, FIG. 5 b a front view, FIG. 5 c a foldout view, and FIG. 5 d an additional view.", "As illustrated in FIG. 5 a , the multi-angle hook 20 includes a member 22 and a member 24 , which, as shown, are at a right angle or substantially a right angle to each other, although this is not essential.", "In fact, the angle between members 22 and 24 can be any angle as long as the angle is capable of a portion of the seat platform 12 , which will be discussed in more detail below with respect to FIGS. 6 a - 6 d .", "The multi-angle hook 20 also includes a member 26 and a member 28 .", "In a preferred embodiment, the multi-angle hook 20 is formed as a single piece, preferably of metal, but also possibly of any type of rigid, sturdy, plastic, wood or any other suitable material.", "As illustrated in FIGS. 5 a and 5 d , the angle between members 22 and 24 is obtuse, in particular, approximately 135° and the angle between members 26 and 28 is a right angle or substantially a right angle to each other, although these values are also not essential.", "In fact, similar to the angle between members 22 and 24 , the angles between members 24 and 26 and members 26 and 28 can be any angle as long as the angles are capable of catching a portion of the seat platform 12 , which will be discussed in more detail below with respect to FIGS. 6 a - 6 d. [0031] As illustrated in FIGS. 5 a - 5 d , the multi-angle hook 20 includes at least one hole 30 for securing the multi-angle hook to the extension 10 .", "In a preferred embodiment, the at least one hole 30 is counter-sunk.", "In another preferred embodiment, the number of holes 30 is three, although any number of holes may be used.", "Further, the manner in which the multi-angle hook 20 is secured to the extension 10 , such as, screws, bolts, nails, rivets, pins, staples, snaps, (or any other suitable fastener), glue (which might obviate the need for holes altogether), etc.", ", is not significant, as long as the multi-angle hook 20 and the extension 10 are secured together.", "[0032] [0032 ]FIGS. 6 a - 6 d illustrate the relationship between the extension 10 , the seat platform 12 , and the multi-angle hook 20 in several positions.", "FIG. 6 a illustrates the bed position, where the extension 10 and the seat platform 12 are both substantially parallel to the floor.", "As illustrated in FIG. 6 a , the multi-angle hook 20 is secured to the extension 10 and the multi-angle hook 20 is arranged such that it catches the seat platform 12 .", "As illustrated, member 22 of the multi-angle hook 20 contacts and is substantially parallel to a top side of the seat platform 12 and member 24 of the multi-angle hook 20 contacts and is substantially parallel to a front side of the seat platform 12 .", "In this manner, the extension 10 is supported by the seat platform 12 at one end and via legs 11 at the other end.", "Further, the multi-angle hook 20 enables the extension to temporarily engage the seat platform 12 , when in the bed position.", "[0033] [0033 ]FIG. 6 b illustrates the steamer position, where the extension 10 and the seat platform 12 are both substantially tilted with respect to the floor.", "As illustrated in FIG. 6 b , the multi-angle hook 20 is secured to the extension 10 and the multi-angle hook 20 is arranged such that it again catches the seat platform 12 .", "As illustrated, member 26 of the multi-angle hook 20 contacts and is substantially parallel to a top side of the seat platform 12 and member 28 of the multi-angle hook 20 contacts and is substantially parallel to a front side of the seat platform 12 .", "In this manner, the extension 10 is supported by the seat platform 12 at one end and via the floor on the other end.", "Further, the multi-angle hook 20 enables the extension to temporarily engage the seat platform 12 , when in the steamer position.", "It may also be advantageous for member 22 to have a notch or indent 21 , at one end to further secure the seat platform 12 .", "It is further noted that member 28 is optional [0034] [0034 ]FIG. 6 c illustrates the lounger position, which is somewhat of a hybrid between the bed position and the steamer position in that the extension 10 may be parallel or substantially parallel to the floor as in the bed position (although the seat platform 12 is not) or the extension 10 may be tilted with respect to the floor, but less tilted than the seat platform 12 in the steamer position.", "As illustrated in FIG. 6 c , the multi-angle hook 20 is secured to the extension 10 and the multi-angle hook 20 is arranged such that it again catches the seat platform 12 .", "As illustrated, member 24 of the multi-angle hook 20 contacts the side of the seat platform 12 and member 22 and/or the extension 10 itself contact the top side of the seat platform 12 .", "In this manner, the extension 10 is supported by the seat platform 12 at one end and via the legs 11 on the other end.", "Further, the multi-angle hook 20 enables the extension to temporarily engage the seat platform 12 , when in the lounger position.", "It may also be advantageous for member 24 and/or member 22 (or the extension 10 itself) to have a notch or indent 21 , to further secure the seat platform 12 .", "[0035] [0035 ]FIG. 6 d illustrates the closed or unextended position, where the slats of the extension 10 are nested within the slats of the seat platform 12 .", "The extension slats slide in between the slats of the seat platform 12 , sliding in and out in relation to them.", "As illustrated in FIG. 6 d , the extension 10 and the seat platform 12 are both substantially tilted with respect to the floor.", "As illustrated in FIG. 6 d , the multi-angle hook 20 is arranged in front of a rear rail of the seat platform 12 .", "As illustrated in FIG. 6 d , there is little or no interaction between the multi-angle hook and the seat platform 12 in the closed or unextended position.", "[0036] [0036 ]FIGS. 7 a - 7 c illustrate the lounger position, the steamer position, and the bed position, respectively, from additional angles.", "[0037] In order to facilitate the attachment of the legs 11 of the extension 10 to the extension 10 itself, it may be advantageous to eliminate side rails from the seat platform 12 .", "As illustrated in FIG. 6 a , the extension 10 includes side rails (as does the back platform 13 ), but the seat platform 12 does not.", "This arrangement allows easy and secure attachment of the legs 11 to the extension 10 .", "[0038] Further, hinging of the seat platform 12 and the back platform 13 may be better achieved by not utilizing the conventional futon frame pivot connection.", "The conventional connection for futon frames is a clevis pin passing through a hole on the back platform side rail 13 ′ and again through a hole in the seat platform side rail thereby coupling the two platforms together.", "Without a seat platform side rail to connect to, the clevis pin passing through the back platform side rail 13 ′ has only the end of the seat long rail to be inserted into.", "The stress on a wood rail, created in this manner, may be excessive and could subject the seat long rail to cracking along the wood grain.", "[0039] [0039 ]FIG. 8 illustrates a solution to this problem, namely an L-shaped hinge attachable to the seat platform 12 for the purpose of coupling the seat platform 12 and the back platform 13 together, allowing the seat platform 12 and the back platform 13 to pivot freely and securely in relation to each other.", "As illustrated in FIG. 8, the seat platform 12 includes a rear long rail 80 , a front long rail 81 , slats 82 , and no side rails.", "The L-shaped hinge 90 gives the required support to the end of the rear long rail 80 , when secured to the back platform side rail 13 ′ of FIG. 6 a. [0040] The seat platform 12 is coupled to the back platform 13 by inserting a clevis pin 100 through a hole in the back platform side rail 13 ′ and into the seat rear long rail 80 , first passing through the L-shaped hinge 90 , which is securely attached to the seat rear long rail 80 .", "[0041] With the clevis pin 100 fully inserted as described, the clevis pin 100 is then locked into place with a conventional locking pin.", "The locking pin is fit through one of one or more holes ( 102 shown in FIGS. 10 e - 10 f ) in and through (substantially perpendicular to) the far tip (away from the head) of the clevis pin 100 .", "[0042] To allow access by the locking pin to the hole at the far tip of the clevis pin 100 while the clevis pin 100 is fully inserted into the seat rear long rail 80 , an access hole 101 is provided in and through (substantially perpendicular to) the surface of the seat rear long rail 80 .", "The relationship between the seat rear long rail 80 , the L-shaped hinge 90 , and the access hole 101 is further illustrated in FIGS. 9 a - 9 d. [0043] [0043 ]FIGS. 10 a - 10 f illustrate an exemplary L-shaped hinge 90 and associated clevis pin 100 , in more detail.", "FIGS. 10 a , 10 b , 10 c , and 10 d illustrate top, isometric, front, and outside views, respectively, of the L-shaped hinge 90 .", "The L-shaped hinge 90 includes at least two flanges 92 , 94 , which form around the end of the seat rear long rail 80 .", "The flanges 92 , 94 include one more holes 91 to secure the L-shaped hinge 90 to the seat rear long rail 80 .", "The holes 91 may be countersunk.", "The flange 94 also includes a hole 93 for the clevis pin 100 .", "As most clearly illustrated in FIG. 10 b , the hole 93 is not countersunk, and in fact, may extend outwardly.", "FIGS. 10 e - 10 f illustrate top and isometric views, respectively of the holes 102 of the clevis pin 100 , in more detail.", "[0044] As illustrated in FIG. 10 e - 10 f , to allow easy insertion of the locking pin into the clevis pin 100 , the clevis pin 100 includes holes 102 , in substantially the same transverse plane, but approximately 90° apart.", "The holes 102 allows easy access for the locking pin to a hole in the clevis pin 100 , regardless of the clevis pin's random rotation in the seat rear long rail 80 .", "[0045] Although each of FIGS. 6 a - 6 d and 7 a - 7 c illustrate two multi-angle hooks, any number of hooks 20 may be utilized.", "Further, although the multi-angle hook 20 of FIGS. 6 a - 6 d and 7 a - 7 c contacts top and front sides of the front rail of the seat platform 12 , the multi-angle hook 20 may contact any surface of the seat platform 12 or the extension 10 to accomplish the desired goal.", "Still further, although the multi-angle hook 20 of FIGS. 6 a - 6 d and 7 a - 7 c is shown as being attached to the extension 10 , the multi-angle hook could also be attached to the seat platform 12 .", "Still further, the multi-angle hook 20 may be configured so that in the lounger position, the extension 10 is inclined with respect to the floor (FIG.", "6 c ) or parallel to the floor (FIG.", "7 a ).", "[0046] It is obvious from FIGS. 6 a and 6 c that member 28 is unnecessary in both the bed and lounger positions.", "It is less obvious that member 28 is also not necessary (although helpful) in the steamer position of FIG. 6 b .", "The weight of the futon mattress can keep the multi-angle hook 20 in place in the steamer position.", "Accordingly, the inclusion of member 28 is considered desirable, but not necessary.", "[0047] As described the present invention is directed to a multi-angle hook and a method of temporarily securing two frame components of a futon bed together.", "The multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention changes the nature of the attachment two frame components of a futon bed by allowing easy and complete removal of one frame component from another.", "The multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention allow one frame component to be freely lifted off another frame component and alternately lowered and set into place.", "[0048] The multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention facilitates conversion of the futon frame into its various positions (bed, steamer, lounger) because the futon frame is easier to manipulate with one of the frame components removed.", "Further, defective parts are easily replaced using the multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention.", "Still further, parts management in manufacturing is simpler using the multi-angle hook and method of temporarily securing two frame components of a futon bed together of the present invention, thereby saving production cost.", "[0049] In a preferred embodiment, the L-shaped hinge 90 is formed as a single piece, preferably of metal, but also possibly of any type of rigid, sturdy, plastic, wood or any other suitable material.", "[0050] In a preferred embodiment, the at least one hole 91 is counter-sunk.", "In another preferred embodiment, the number of holes 91 is four, although any number of holes may be used.", "Further, the manner in which the L-shaped hinge 90 is secured to the back platform 12 , such as, screws, bolts, nails, rivets, pins other than clevis pins, staples, snaps, (or any other suitable fastener), glue (which might obviate the need for holes altogether), etc.", ", is not significant, as long as the L-shaped hinge 90 and the back platform 12 are secured together.", "[0051] It is further noted that, although in the embodiments described above, the seat platform 12 does not include side rails, it may be the back platform 13 or extension 10 (or any combination thereof) which does include side rails.", "[0052] It is further noted that the hinge need not be L-shaped or even substantially L-shaped, but merely of a shape to substantially conform to the end of the seat platform 12 , back platform 13 or extension 10 .", "[0053] As described the present invention is directed an L-shaped hinge and a method of temporarily securing two frame components of a futon bed together.", "[0054] The invention being thus described, it will be obvious that the same may be varied in many ways.", "Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims." ]
FIELD OF THE INVENTION This invention relates generally to wireless communication systems and in particular to time synchronization correction of an in-band translator deployed in peripheral cells to extend the range of a Base Transceiver System (BTS). BACKGROUND OF THE INVENTION The need for wireless communication services, such as Cellular Mobile Telephone (CMT), Personal Communication Services (PCS) and the like, typically requires the operators of such systems to serve an ever increasing number of users. As a result, certain types of multichannel broadband Base Transceiver Systems (BTSs) have been developed which are intended to service a relatively large number of active mobile stations in each cell. Such broadband BTS equipment can typically service ninety-six simultaneously active mobile stations, at a cost of less than $2000 to $4000 per channel. While this equipment is cost effective to deploy when a relatively large number of active mobile stations is expected in each cell, it is not particularly cost effective in most other situations. For example, during an initial system build out phase, a service provider does not actually need to use large numbers of radio channels. As a result, the investment in broadband multichannel radio equipment may not be justified until such time as the number of subscribers increases to a point where the channels are busy most of the time. Some have proposed various techniques for expanding the service area of a master cell site. For example, the HPT Cell Site Expander product manufactured by 3 dbm, Inc., of Camarillo, Calif., consists of a base station translator which samples downlink signal traffic and translates it to a selected offset frequency. The offset carrier is transmitted to an expansion cell site via directional antennas. At the expansion cell site, the carrier is translated back to the original cellular channel and transmitted throughout the expansion cell site coverage area such as via an omnidirectional antenna. In the uplink direction, a cellular signal received by the expansion cell site from a mobile unit is translated and then transmitted back to the base station translator, which in turn translates the signal back to its original carrier frequency. However, such a device is designed only for use with analog-type cellular systems. A specific problem is encountered when attempting to extend the service area of a base station that uses Time Division Multiple Access (TDMA) signaling. Such a system makes use of a technique in which multiple voice or data channels are provided by dividing the access to each radio carrier frequency into carefully synchronized time slots. In order to properly demodulate a TDMA signal at the base station, a timing advance must be taken into consideration for each radio pulse received from the mobile stations. The timing advance serves to compensate for the differences in signal propagation time since the distance to the base station is different for each mobile station. A TDMA signal transmitted in the uplink direction must therefore arrive at the Base Transceiver System with proper time alignment. If this is not the case, the signal pulses from the various mobile stations will collide, and it will not be possible for the Base Transceiver System to properly demodulate the signals. As such, it has in most instances been necessary to limit the nominal radius of a TDMA cell so that proper time alignment may be maintained. An approach to extending the radius of a TDMA cell was disclosed in U.S. Pat. No. 5,544,171, issued to Goedecker and assigned to Alcatel N.V. This technique uses a fixed Base Transceiver System (BTS) that includes both a standard TDMA radio receiver and an additional auxiliary TDMA receiver. The auxiliary TDMA receiver receives and compensates the TDMA radio pulses from mobile stations located outside of the nominal cell radius. In this manner, interference between the TDMA signals received from a mobile station located outside of the nominal cell radius and a mobile station located within the nominal radius is avoided. Unfortunately, the Goedecker technique is intended for use where both radio transceivers can be located entirely within the base station site. This permits the timing signals for the auxiliary TDMA receiver to be directly connected to the timing signals for the standard TDMA receiver. Thus, it would not be possible to directly apply the Goedecker technique to a remote repeater or translator arrangement, where the auxiliary TDMA receiver would have to be located many miles away from the base station site and such timing signal connection would not be possible. Furthermore, while the HPT and Goedecker designs can be used to extend the radius of a single cell, they do not appear to suggest how to synchronize TDMA signals received from multiple mobile stations located in multiple cells simultaneously. DESCRIPTION OF THE INVENTION Objects of the Invention It is an object of this invention to extend the available range in a cellular communication system beyond that which is normally available with Time Division Multiple Access (TDMA) air interfaces. Another object is to provide for time delay compensation in TDMA systems without using multiple auxiliary receivers. A further object is to compensate for the delay associated between a translating receiver deployed in a remote outlying cell and a host base station. Yet another object is to provide for remote receiver time delay compensation in an uplink direction by measuring a delay observed in a downlink direction. SUMMARY OF THE INVENTION Briefly, the invention is an architecture for a wireless communication system in which the cells are grouped into clusters. A host cell location is identified within each cluster and a multichannel Base Transceiver System (BTS) is located at or near the host cell site. Rather than deploy a complete suite of base station equipment at each remaining cell in the cluster, translating radio transceivers are located in the remote cells. These translating radio transceivers operate in-band, that is, within the frequencies assigned to the service provider. The in-band translators operate in both an uplink and downlink direction. That is, signals transmitted by a mobile station located in a remote cell are received at the in-band translator, translated to a different carrier frequency, and then transmitted to the host BTS. Likewise, signals transmitted by the host BTS are first received by the in-band translator, translated to a different carrier frequency, and then repeated out to the mobile stations. In accordance with the invention, the host BTS measures a time delay for each in-band translator channel during a calibration mode. This is accomplished by setting the in-band translator to a loop back mode whereby the downlink signal received from the host BTS is looped an intermediate frequency (IF) signal chain back to the uplink transmit path. A timing test signal in the form of, for example, an access burst is then transmitted by the host BTS such as would normally be sent by a mobile station. The access burst is received by the in-band translator and looped back to the host BTS. The host BTS then demodulates the looped back signal. A resulting time of arrival delay estimate as measured in the downlink path is then used by the host BTS to compensate for time alignments to be made in the time slots in the uplink signal during normal operation. As a result, the limitation on the range of the cell site normally associated with Time Division Multiple Access protocols is avoided. Indeed the range of such a system is limited only by the expected attenuation in the radio link. BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the invention and its novel advantages and features, reference should be made to the accompanying drawings in which: FIG. 1 is a view of a cell site cluster showing how a host Base Transceiver System (BTS), in-band translators, and mobile stations are deployed according to the invention; FIG. 2 is a block diagram of the components of the system; FIG. 3 is a detailed block diagram of a preferred embodiment of the multichannel host Base Transceiver System (BTS); FIG. 4 is a block diagram of the in-band translator (or range extender); FIG. 5 is a flow chart of the sequence of steps performed by a transmit control processor in the host BTS during a time of arrival measurement procedure; and FIG. 6 is a flow chart of the sequence of steps performed by a receive digital signal processor in the host BTS while processing TDMA signal samples to compensate for the measured time of arrival. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates a wireless communication system 10 such as a Cellular Mobile Telephone, Personal Communication System (PCS), or similar system in which a timing adjustment scheme according to the invention enables proper demodulation signals received from in-band frequency translator base stations deployed in peripheral cells. The system 10 provides voice and or data communication between mobile stations 20 and a Public Switched Telephone Network (PSTN) via radio signals. In the particular embodiment of the invention being described, the radio signaling protocol, or "air interface", uses a Time Division Multiple Access (TDMA) technique such as the PCS-1900 standard promulgated by the Telecommunications Industry Association (TIA) in the United States which is identical in relevant aspects to the Global System for Mobile Communication (GSM) standard promulgated in Europe and elsewhere by the European Telecommunication Standards Institute (ETSI)!. The in-band translators 12-1, 12-2, . . . , 12-n (also referred to herein as the "range extenders") are each located in what is normally to be approximately the center of a cell site 22 among a group or cluster 24 of cells. The in-band translators 12 receive radio signals from the mobile stations 20 located in their respective cells 22 and forward these signals to the associated host Base Transceiver System (BTS) 15. Likewise, radio signals originating at the host BTS 15 are forwarded by the translators 12 to the mobile stations 20. As a result, the signals associated with all of the mobile stations 20 located within the cluster 24 of cells 22-1, . . . , 22-n are thereby processed at the host BTS 15. The in-band translators 12 are "base stations" in the sense that they are each associated with a particular cell 22 and in that they each receive and transmit multiple signals from and to the mobile stations 20. However, the in-band translators 12 do not perform demodulation and modulation functions as does a conventional base station radio. Rather, they serve only to perform an in-band frequency-translation on signals received from the mobile stations 20 and then direct such signals on a different frequency to the host BTS 15. The in-band translators 12 also perform the inverse function, to frequency translate signals received from the host BTS 15-1 and then direct them to the mobile stations 20. The specific manner of translation will be discussed below in connection with FIG. 4. Turning attention now to FIG. 2, the system 10 more particularly includes translator omni-directional antennas 11-1, . . . , 11-n-2, 11-n-1, 11-n (collectively, the omni-directional antennas 11), in-band translator base stations (range extenders) 12-1-1, . . . , 12-n-1, . . . , 12-n-12, translator directional antennas 13-1, . . . , 13-n, host base station antennas 14-1, . . . , 14-n, multichannel host Base Transceiver Systems (BTSs) 15-1, . . . 15-n, one or more base station controllers 16, a mobile switching center 18, and mobile stations 20-1, 20-2. The host BTSs 15-1, . . . , 15-n are responsible for demodulating radio signals as well as for connecting such signals to the Public Switched Telephone Network (PSTN) through the mobile exchange 17. The host BTSs 15-1, 15-n also modulate signals received from the PSTN through the mobile switching center 18 to format them for transmission over the air through the in-band translators 12. A particular host BTS 15-1 serves the multiple in-band translators 12-1-1, 12-1-2, . . . , 12-1-n associated with a given cluster 24 of cells 22. The Base Station Controller (BSC) 16, of which there may be more than one, has a number of functions. The primary function is to manage the logical connections made between mobile stations 20 and the PSTN. In order to do so, the Base Station Controller 16 assigns transmit and receive radio carrier frequencies to each individual mobile station 20, in-band translator 12, and host BTS 15. Typically, there may be five to twenty BTSs 15-1, . . . , 15-n serviced by a single Base Station Controller 16. Turning attention now to FIG. 3, an exemplary host Base Transceiver System (BTS) 15 consists of a broadband transceiver portion 40 and transceiver control processor 50. The transceiver portion 40 acts as the interface for the radio channels Um, and preferably includes broadband radio receiver and transmitter equipment to provide access to a number of contiguous receive and transmit channels simultaneously. The transceiver control processor 50 coordinates the operation of the transceiver portion 40 according to commands received from the Base Station Controller (BSC) 16 over an interface known as the Abis interface. The broadband multichannel receiver 45 and transmitter 49 are broadband in the sense that they cover a substantial portion of the radio frequency bandwidth available to the service provider operating the system 10. For example, the broadband receiver 43 may downconvert a 5 MegaHertz (MHz) bandwidth in the 1900-2000 MHz range which contains as many as 25 radio carrier signals, each having an approximately 200 kiloHertz (kHz) bandwidth. Each such carrier signal may typically contain up to eight (8) PCS-1900 channel signals. The transceiver portion 40 consists of a broadband multichannel receiver 43 and a broadband multichannel transmitter 49. The broadband multichannel receiver 43 in turn typically consists of a downconverter analog-to-digital (A/D) and one or more digital filter bank analyzers (not shown) which operate in a known manner to provide a plurality, N, of digital channel signals. A plurality of digital signal processors (DSPs) receive the digital channel signals and are programmed to operate as demodulators 44-1, 44-2, . . . , 44-p (collectively demodulator DSPs 44). The demodulator DSPs 44 are connected to the broadband multichannel receiver 43 via a Time Division Multiplex (TDM) bus, which permits any of the N receiver outputs to be connected to any demodulator DSP 44. The demodulator DSPs 44 each provide a demodulated radio signal at its output. An encoder 45 may be used to encode these outputs of the demodulator DSPs 44 into a suitable signaling format for transport over the Abis interface to the Base Station Controller (BSC) 16. The transceiver 40 performs the reciprocal functions in the transmit direction. In particular, a decoder 46 and a plurality of modulator DSPs 48-1, 48-2, . . . , 48-p, each of which receive one of the channel signals at an input, provide a plurality, N, of modulated signals to the broadband multichannel transmitter 49. The broadband multichannel transmitter 49, which is also connected to the TDM bus, consists of a digital filter bank synthesizer and a digital-to-analog converter. The broadband multichannel transmitter combines the N modulated signals to produce a broadband composite signal for transmission. The transceiver control processor 50 is a computer, such as a microcomputer, and includes a central processing unit (CPU) 52, a memory 53, an input/output (I/O) interface 54, and bus controller interface 55. The I/O interface 54 is used to receive control signaling from the BSC 16 over the Abis interface. To facilitate communication with the broadband transceiver 40, the transceiver control processor 50 makes use of the Time Division Multiplex (TDM) bus controller 55. The bus controller 55 ensures that output from the broadband multichannel receiver 43 are inserted in a defined order to particular ones of the demodulator DSPs 44. Likewise, the bus controller 55 ensures that outputs of the modulator DSPs 48 are asserted in the defined order to the N inputs of the broadband multichannel transmitter 49. The bus controller 55 accomplishes this in a known fashion by using a bus time slot counter and time slot memory circuits to determine the order of connections. A co-pending United States patent application entitled "Transceiver Apparatus Employing Wideband FFT Channelizer with Output Sample Timing Adjustment and Inverse FFT Combiner for a Multichannel Communication Network" filed Apr. 8, 1994 and which is assigned to AirNet Communications Corporation, the assignee of this application, describes the details of several embodiments of the multichannel BTS 15. FIG. 4 is a block diagram of the details of one of the in-band translators 12 according to the invention. The in-band translator 12 consists of an omni-directional antenna 11, a directional antenna 13, a backhaul-to-ground frequency translator 100, a directional coupler 102, a loop-back switch 104, a ground-to-backhaul frequency translator 106, a ping signal detector 110, a frequency shifter 109, and a diversity detector 108. The backhaul-to-ground translator 100 receives signals from the directional antenna from the host BTS 15. The backhaul-to-ground translator 100 shifts the carrier frequency of such signals to a different frequency which is within the bandwidth of the frequency allocated to the operator of the system 10. In a PCS-1900 system, for example, signals may be received from the host BTS 15 in a range of, say, 1975-1990 MHz. As previously described, each signal is, a 200 kHz bandwidth signal. The signal is then frequency translated to a different carrier frequency in the 1975-1990 MHz bandwidth. The translated signal is then sent through the directional coupler 102 out to the omni-directional antenna 11, and from there, on to the mobile stations 20. In the receive direction, radio carrier frequency signals received on the omni-directional antenna 11 from the mobile stations 20 are first passed to the loop back switch 104. In this normal mode of operation of the in-band translator 12, the loop back switch 104 is set to couple signals received at the omni-directional antenna 11 to the ground-to-backhaul frequency translator 106. The ground-to-backhaul translator 106 then performs a carrier frequency translation. For example, in the PCS 1900 band, signals may be received in a range from 1895-1910 MHz and shifted to a different carrier frequency in this bandwidth. The output from the ground-to-backhaul translator 106 is then connected to the directional antenna 13 for transmission back to the host BTS 15. The ping signal detector 110 is arranged to detect an initiate loop back or "ping"signal as sent by the BTS 15. Upon first detecting the initiate loop back signal, the ping signal detector 110 causes the loop back switch 104 to be operated to connect signals received on the omnidirectional antenna through the backhaul to ground translator 100, the coupler 102, the loop back switch 104, and ground-to-backhaul translator 106. While the translator 12 is in this loop back mode, a frequency offset circuit 109 adjusts for the difference in the downlink and uplink carrier frequency. This offset is (1975 minus 1895) or 80 MHz in the PCS-1900 example being described herein. When a subsequent terminate loop back signal is received by the ping signal detector 110, the loop-back switch 104 is operated to return the translator 12 to the normal mode. In order to perform a time of arrival adjustment according to the invention, the in-band translator 12 having a loop-back mode is used in conjunction with the host BTS 15. In particular, the BTS control processor 52 (FIG. 3), includes a process that tracks of the activity for each in-band translator 12 which it controls. The process proceeds generally as follows. When there has been no radio frequency signal transmitted to or by a mobile station 20 on the carrier frequency associated with a particular in-band translator 12 for a period of time, such as, for example, five (5) minutes, the control processor 52 sends a command to the transmit digital signal processor (DSP) 48 associated with that particular radio channel. That DSP 48 in turn causes the initiate loop back ping signal to be sent to the in-band translator 12. The ping signal may, for example, take the form of a constant baseband tone transmitted for a predetermined number of successive time slots. After waiting for a period of time sufficient to ensure that the in-band translator 12 has been placed into loop back mode, the DSP 48 then causes a timing test signal, such as a Random Access Control Channel (RACCH) burst to be sent to the translator 12. The corresponding receive DSP 44 is then initiated to detect the RACCH burst and to measure the time required for the RACCH burst to be looped back to the host BTS 15. In this manner, the host BTS 15 can determine an actual propagation time between the in-band translator 12 and the base station 15, by dividing the observed loop back time by two. After determining the propagation time, the loop back termination signal (which may be in the form of a tone that is different from the initiate loop back tone) causes the ping return detector 110 to return the loop back switch 104 to the normal mode. The process may be repeated and measurements averaged if desired. FIG. 5 contains a flow chart of the steps performed by the BTS control processor 50 during the time of arrival measurement process for a particular translator 12. In a first step 200, a particular one of the in-band translators 12 has been detected as being inactive for the pre-determined period of time. In a next step 202, the associated transmit DSP 48 is requested to send initiate loop back ping signal. The following step 204 causes the processor 50 to enter a wait state for a pre-determined time frame, after which in step 206 DSP 44 is asked to send the RACCH burst signals. In the next step 208, a timer is started with step 208 preferably occurring concurrently with step 206. In step 210, the return RACCH bursts are reported as being detected by the associated receiving DSP 44. In step 212, the timer data is read. In step 214, the terminate loop back ping signal is transmitted back to the in-band translator 12. In the final step 218 the offset time "t" is calculated by averaging the results of the repeated timing interval measurements and dividing by two. The process is repeated for each of the translators in the cluster 24 to determine a time interval measurement for each. FIG. 6 illustrates a sequence of steps performed by a receive DSP 44 during normal operation in connection with the invention. In a first step 220, the channel samples are read as in the normal demodulation processes as previously described. In a next step 222, the channel sample timing references are offset by the time "t" as determined from the process for the associated translator 12, as previously described in FIG. 5. In the next step 224, the channel samples are then further processed as for normal Time Division Multiple Access (TDMA) demodulation. It is now understood how the invention is able to compensate for the propagation delay between the in-band translator 12 and the host BTS 15. Computer simulations of an implementation of the invention has been shown that with a single host BTS 15 and twelve cells 22, coverage can be provided of approximately 1000 square kilometers by a single BTS 15 which would previously have been limited to a radius of 35 kilometers. This is accomplished by determining a fixed timing offset parameter for each in-band translator, by setting the in-band translator into a loop back mode via a transmission of a special loop back signal, transmitting an access burst as would normally be sent by a mobile unit, measuring the time of arrival delay at the BTS, and then using this measured time of arrival delay to determine an offset to be used to adjust the normal mode TDMA-demodulation processing.
In a conventional Time Division Multiple Access (TDMA) wireless system, the specified distance between a mobile unit and the base transceiver system (BTS) cannot exceed predetermined distances because of time slot synchronization constraints. In this approach to extending TDMA system coverage, in-band translator components are located in the center of remote cells which would normally contain a base transceiver system (BTS). The in-band translators include a loop back circuit that permits a host BTS to measure the propagation time delay by sending test access signals between the host BTS and each in-band translator. The measurements are then used to adjust a time delay in an uplink signal as received from each in-band translator by the BTS in normal operation.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "FIELD OF THE INVENTION This invention relates generally to wireless communication systems and in particular to time synchronization correction of an in-band translator deployed in peripheral cells to extend the range of a Base Transceiver System (BTS).", "BACKGROUND OF THE INVENTION The need for wireless communication services, such as Cellular Mobile Telephone (CMT), Personal Communication Services (PCS) and the like, typically requires the operators of such systems to serve an ever increasing number of users.", "As a result, certain types of multichannel broadband Base Transceiver Systems (BTSs) have been developed which are intended to service a relatively large number of active mobile stations in each cell.", "Such broadband BTS equipment can typically service ninety-six simultaneously active mobile stations, at a cost of less than $2000 to $4000 per channel.", "While this equipment is cost effective to deploy when a relatively large number of active mobile stations is expected in each cell, it is not particularly cost effective in most other situations.", "For example, during an initial system build out phase, a service provider does not actually need to use large numbers of radio channels.", "As a result, the investment in broadband multichannel radio equipment may not be justified until such time as the number of subscribers increases to a point where the channels are busy most of the time.", "Some have proposed various techniques for expanding the service area of a master cell site.", "For example, the HPT Cell Site Expander product manufactured by 3 dbm, Inc., of Camarillo, Calif.", ", consists of a base station translator which samples downlink signal traffic and translates it to a selected offset frequency.", "The offset carrier is transmitted to an expansion cell site via directional antennas.", "At the expansion cell site, the carrier is translated back to the original cellular channel and transmitted throughout the expansion cell site coverage area such as via an omnidirectional antenna.", "In the uplink direction, a cellular signal received by the expansion cell site from a mobile unit is translated and then transmitted back to the base station translator, which in turn translates the signal back to its original carrier frequency.", "However, such a device is designed only for use with analog-type cellular systems.", "A specific problem is encountered when attempting to extend the service area of a base station that uses Time Division Multiple Access (TDMA) signaling.", "Such a system makes use of a technique in which multiple voice or data channels are provided by dividing the access to each radio carrier frequency into carefully synchronized time slots.", "In order to properly demodulate a TDMA signal at the base station, a timing advance must be taken into consideration for each radio pulse received from the mobile stations.", "The timing advance serves to compensate for the differences in signal propagation time since the distance to the base station is different for each mobile station.", "A TDMA signal transmitted in the uplink direction must therefore arrive at the Base Transceiver System with proper time alignment.", "If this is not the case, the signal pulses from the various mobile stations will collide, and it will not be possible for the Base Transceiver System to properly demodulate the signals.", "As such, it has in most instances been necessary to limit the nominal radius of a TDMA cell so that proper time alignment may be maintained.", "An approach to extending the radius of a TDMA cell was disclosed in U.S. Pat. No. 5,544,171, issued to Goedecker and assigned to Alcatel N.V.", "This technique uses a fixed Base Transceiver System (BTS) that includes both a standard TDMA radio receiver and an additional auxiliary TDMA receiver.", "The auxiliary TDMA receiver receives and compensates the TDMA radio pulses from mobile stations located outside of the nominal cell radius.", "In this manner, interference between the TDMA signals received from a mobile station located outside of the nominal cell radius and a mobile station located within the nominal radius is avoided.", "Unfortunately, the Goedecker technique is intended for use where both radio transceivers can be located entirely within the base station site.", "This permits the timing signals for the auxiliary TDMA receiver to be directly connected to the timing signals for the standard TDMA receiver.", "Thus, it would not be possible to directly apply the Goedecker technique to a remote repeater or translator arrangement, where the auxiliary TDMA receiver would have to be located many miles away from the base station site and such timing signal connection would not be possible.", "Furthermore, while the HPT and Goedecker designs can be used to extend the radius of a single cell, they do not appear to suggest how to synchronize TDMA signals received from multiple mobile stations located in multiple cells simultaneously.", "DESCRIPTION OF THE INVENTION Objects of the Invention It is an object of this invention to extend the available range in a cellular communication system beyond that which is normally available with Time Division Multiple Access (TDMA) air interfaces.", "Another object is to provide for time delay compensation in TDMA systems without using multiple auxiliary receivers.", "A further object is to compensate for the delay associated between a translating receiver deployed in a remote outlying cell and a host base station.", "Yet another object is to provide for remote receiver time delay compensation in an uplink direction by measuring a delay observed in a downlink direction.", "SUMMARY OF THE INVENTION Briefly, the invention is an architecture for a wireless communication system in which the cells are grouped into clusters.", "A host cell location is identified within each cluster and a multichannel Base Transceiver System (BTS) is located at or near the host cell site.", "Rather than deploy a complete suite of base station equipment at each remaining cell in the cluster, translating radio transceivers are located in the remote cells.", "These translating radio transceivers operate in-band, that is, within the frequencies assigned to the service provider.", "The in-band translators operate in both an uplink and downlink direction.", "That is, signals transmitted by a mobile station located in a remote cell are received at the in-band translator, translated to a different carrier frequency, and then transmitted to the host BTS.", "Likewise, signals transmitted by the host BTS are first received by the in-band translator, translated to a different carrier frequency, and then repeated out to the mobile stations.", "In accordance with the invention, the host BTS measures a time delay for each in-band translator channel during a calibration mode.", "This is accomplished by setting the in-band translator to a loop back mode whereby the downlink signal received from the host BTS is looped an intermediate frequency (IF) signal chain back to the uplink transmit path.", "A timing test signal in the form of, for example, an access burst is then transmitted by the host BTS such as would normally be sent by a mobile station.", "The access burst is received by the in-band translator and looped back to the host BTS.", "The host BTS then demodulates the looped back signal.", "A resulting time of arrival delay estimate as measured in the downlink path is then used by the host BTS to compensate for time alignments to be made in the time slots in the uplink signal during normal operation.", "As a result, the limitation on the range of the cell site normally associated with Time Division Multiple Access protocols is avoided.", "Indeed the range of such a system is limited only by the expected attenuation in the radio link.", "BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the invention and its novel advantages and features, reference should be made to the accompanying drawings in which: FIG. 1 is a view of a cell site cluster showing how a host Base Transceiver System (BTS), in-band translators, and mobile stations are deployed according to the invention;", "FIG. 2 is a block diagram of the components of the system;", "FIG. 3 is a detailed block diagram of a preferred embodiment of the multichannel host Base Transceiver System (BTS);", "FIG. 4 is a block diagram of the in-band translator (or range extender);", "FIG. 5 is a flow chart of the sequence of steps performed by a transmit control processor in the host BTS during a time of arrival measurement procedure;", "and FIG. 6 is a flow chart of the sequence of steps performed by a receive digital signal processor in the host BTS while processing TDMA signal samples to compensate for the measured time of arrival.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates a wireless communication system 10 such as a Cellular Mobile Telephone, Personal Communication System (PCS), or similar system in which a timing adjustment scheme according to the invention enables proper demodulation signals received from in-band frequency translator base stations deployed in peripheral cells.", "The system 10 provides voice and or data communication between mobile stations 20 and a Public Switched Telephone Network (PSTN) via radio signals.", "In the particular embodiment of the invention being described, the radio signaling protocol, or "air interface", uses a Time Division Multiple Access (TDMA) technique such as the PCS-1900 standard promulgated by the Telecommunications Industry Association (TIA) in the United States which is identical in relevant aspects to the Global System for Mobile Communication (GSM) standard promulgated in Europe and elsewhere by the European Telecommunication Standards Institute (ETSI)!", "The in-band translators 12-1, 12-2, .", ", 12-n (also referred to herein as the "range extenders") are each located in what is normally to be approximately the center of a cell site 22 among a group or cluster 24 of cells.", "The in-band translators 12 receive radio signals from the mobile stations 20 located in their respective cells 22 and forward these signals to the associated host Base Transceiver System (BTS) 15.", "Likewise, radio signals originating at the host BTS 15 are forwarded by the translators 12 to the mobile stations 20.", "As a result, the signals associated with all of the mobile stations 20 located within the cluster 24 of cells 22-1, .", ", 22-n are thereby processed at the host BTS 15.", "The in-band translators 12 are "base stations"", "in the sense that they are each associated with a particular cell 22 and in that they each receive and transmit multiple signals from and to the mobile stations 20.", "However, the in-band translators 12 do not perform demodulation and modulation functions as does a conventional base station radio.", "Rather, they serve only to perform an in-band frequency-translation on signals received from the mobile stations 20 and then direct such signals on a different frequency to the host BTS 15.", "The in-band translators 12 also perform the inverse function, to frequency translate signals received from the host BTS 15-1 and then direct them to the mobile stations 20.", "The specific manner of translation will be discussed below in connection with FIG. 4. Turning attention now to FIG. 2, the system 10 more particularly includes translator omni-directional antennas 11-1, .", ", 11-n-2, 11-n-1, 11-n (collectively, the omni-directional antennas 11), in-band translator base stations (range extenders) 12-1-1, .", ", 12-n-1, .", ", 12-n-12, translator directional antennas 13-1, .", ", 13-n, host base station antennas 14-1, .", ", 14-n, multichannel host Base Transceiver Systems (BTSs) 15-1, .", "15-n, one or more base station controllers 16, a mobile switching center 18, and mobile stations 20-1, 20-2.", "The host BTSs 15-1, .", ", 15-n are responsible for demodulating radio signals as well as for connecting such signals to the Public Switched Telephone Network (PSTN) through the mobile exchange 17.", "The host BTSs 15-1, 15-n also modulate signals received from the PSTN through the mobile switching center 18 to format them for transmission over the air through the in-band translators 12.", "A particular host BTS 15-1 serves the multiple in-band translators 12-1-1, 12-1-2, .", ", 12-1-n associated with a given cluster 24 of cells 22.", "The Base Station Controller (BSC) 16, of which there may be more than one, has a number of functions.", "The primary function is to manage the logical connections made between mobile stations 20 and the PSTN.", "In order to do so, the Base Station Controller 16 assigns transmit and receive radio carrier frequencies to each individual mobile station 20, in-band translator 12, and host BTS 15.", "Typically, there may be five to twenty BTSs 15-1, .", ", 15-n serviced by a single Base Station Controller 16.", "Turning attention now to FIG. 3, an exemplary host Base Transceiver System (BTS) 15 consists of a broadband transceiver portion 40 and transceiver control processor 50.", "The transceiver portion 40 acts as the interface for the radio channels Um, and preferably includes broadband radio receiver and transmitter equipment to provide access to a number of contiguous receive and transmit channels simultaneously.", "The transceiver control processor 50 coordinates the operation of the transceiver portion 40 according to commands received from the Base Station Controller (BSC) 16 over an interface known as the Abis interface.", "The broadband multichannel receiver 45 and transmitter 49 are broadband in the sense that they cover a substantial portion of the radio frequency bandwidth available to the service provider operating the system 10.", "For example, the broadband receiver 43 may downconvert a 5 MegaHertz (MHz) bandwidth in the 1900-2000 MHz range which contains as many as 25 radio carrier signals, each having an approximately 200 kiloHertz (kHz) bandwidth.", "Each such carrier signal may typically contain up to eight (8) PCS-1900 channel signals.", "The transceiver portion 40 consists of a broadband multichannel receiver 43 and a broadband multichannel transmitter 49.", "The broadband multichannel receiver 43 in turn typically consists of a downconverter analog-to-digital (A/D) and one or more digital filter bank analyzers (not shown) which operate in a known manner to provide a plurality, N, of digital channel signals.", "A plurality of digital signal processors (DSPs) receive the digital channel signals and are programmed to operate as demodulators 44-1, 44-2, .", ", 44-p (collectively demodulator DSPs 44).", "The demodulator DSPs 44 are connected to the broadband multichannel receiver 43 via a Time Division Multiplex (TDM) bus, which permits any of the N receiver outputs to be connected to any demodulator DSP 44.", "The demodulator DSPs 44 each provide a demodulated radio signal at its output.", "An encoder 45 may be used to encode these outputs of the demodulator DSPs 44 into a suitable signaling format for transport over the Abis interface to the Base Station Controller (BSC) 16.", "The transceiver 40 performs the reciprocal functions in the transmit direction.", "In particular, a decoder 46 and a plurality of modulator DSPs 48-1, 48-2, .", ", 48-p, each of which receive one of the channel signals at an input, provide a plurality, N, of modulated signals to the broadband multichannel transmitter 49.", "The broadband multichannel transmitter 49, which is also connected to the TDM bus, consists of a digital filter bank synthesizer and a digital-to-analog converter.", "The broadband multichannel transmitter combines the N modulated signals to produce a broadband composite signal for transmission.", "The transceiver control processor 50 is a computer, such as a microcomputer, and includes a central processing unit (CPU) 52, a memory 53, an input/output (I/O) interface 54, and bus controller interface 55.", "The I/O interface 54 is used to receive control signaling from the BSC 16 over the Abis interface.", "To facilitate communication with the broadband transceiver 40, the transceiver control processor 50 makes use of the Time Division Multiplex (TDM) bus controller 55.", "The bus controller 55 ensures that output from the broadband multichannel receiver 43 are inserted in a defined order to particular ones of the demodulator DSPs 44.", "Likewise, the bus controller 55 ensures that outputs of the modulator DSPs 48 are asserted in the defined order to the N inputs of the broadband multichannel transmitter 49.", "The bus controller 55 accomplishes this in a known fashion by using a bus time slot counter and time slot memory circuits to determine the order of connections.", "A co-pending United States patent application entitled "Transceiver Apparatus Employing Wideband FFT Channelizer with Output Sample Timing Adjustment and Inverse FFT Combiner for a Multichannel Communication Network"", "filed Apr. 8, 1994 and which is assigned to AirNet Communications Corporation, the assignee of this application, describes the details of several embodiments of the multichannel BTS 15.", "FIG. 4 is a block diagram of the details of one of the in-band translators 12 according to the invention.", "The in-band translator 12 consists of an omni-directional antenna 11, a directional antenna 13, a backhaul-to-ground frequency translator 100, a directional coupler 102, a loop-back switch 104, a ground-to-backhaul frequency translator 106, a ping signal detector 110, a frequency shifter 109, and a diversity detector 108.", "The backhaul-to-ground translator 100 receives signals from the directional antenna from the host BTS 15.", "The backhaul-to-ground translator 100 shifts the carrier frequency of such signals to a different frequency which is within the bandwidth of the frequency allocated to the operator of the system 10.", "In a PCS-1900 system, for example, signals may be received from the host BTS 15 in a range of, say, 1975-1990 MHz.", "As previously described, each signal is, a 200 kHz bandwidth signal.", "The signal is then frequency translated to a different carrier frequency in the 1975-1990 MHz bandwidth.", "The translated signal is then sent through the directional coupler 102 out to the omni-directional antenna 11, and from there, on to the mobile stations 20.", "In the receive direction, radio carrier frequency signals received on the omni-directional antenna 11 from the mobile stations 20 are first passed to the loop back switch 104.", "In this normal mode of operation of the in-band translator 12, the loop back switch 104 is set to couple signals received at the omni-directional antenna 11 to the ground-to-backhaul frequency translator 106.", "The ground-to-backhaul translator 106 then performs a carrier frequency translation.", "For example, in the PCS 1900 band, signals may be received in a range from 1895-1910 MHz and shifted to a different carrier frequency in this bandwidth.", "The output from the ground-to-backhaul translator 106 is then connected to the directional antenna 13 for transmission back to the host BTS 15.", "The ping signal detector 110 is arranged to detect an initiate loop back or "ping"signal as sent by the BTS 15.", "Upon first detecting the initiate loop back signal, the ping signal detector 110 causes the loop back switch 104 to be operated to connect signals received on the omnidirectional antenna through the backhaul to ground translator 100, the coupler 102, the loop back switch 104, and ground-to-backhaul translator 106.", "While the translator 12 is in this loop back mode, a frequency offset circuit 109 adjusts for the difference in the downlink and uplink carrier frequency.", "This offset is (1975 minus 1895) or 80 MHz in the PCS-1900 example being described herein.", "When a subsequent terminate loop back signal is received by the ping signal detector 110, the loop-back switch 104 is operated to return the translator 12 to the normal mode.", "In order to perform a time of arrival adjustment according to the invention, the in-band translator 12 having a loop-back mode is used in conjunction with the host BTS 15.", "In particular, the BTS control processor 52 (FIG.", "3), includes a process that tracks of the activity for each in-band translator 12 which it controls.", "The process proceeds generally as follows.", "When there has been no radio frequency signal transmitted to or by a mobile station 20 on the carrier frequency associated with a particular in-band translator 12 for a period of time, such as, for example, five (5) minutes, the control processor 52 sends a command to the transmit digital signal processor (DSP) 48 associated with that particular radio channel.", "That DSP 48 in turn causes the initiate loop back ping signal to be sent to the in-band translator 12.", "The ping signal may, for example, take the form of a constant baseband tone transmitted for a predetermined number of successive time slots.", "After waiting for a period of time sufficient to ensure that the in-band translator 12 has been placed into loop back mode, the DSP 48 then causes a timing test signal, such as a Random Access Control Channel (RACCH) burst to be sent to the translator 12.", "The corresponding receive DSP 44 is then initiated to detect the RACCH burst and to measure the time required for the RACCH burst to be looped back to the host BTS 15.", "In this manner, the host BTS 15 can determine an actual propagation time between the in-band translator 12 and the base station 15, by dividing the observed loop back time by two.", "After determining the propagation time, the loop back termination signal (which may be in the form of a tone that is different from the initiate loop back tone) causes the ping return detector 110 to return the loop back switch 104 to the normal mode.", "The process may be repeated and measurements averaged if desired.", "FIG. 5 contains a flow chart of the steps performed by the BTS control processor 50 during the time of arrival measurement process for a particular translator 12.", "In a first step 200, a particular one of the in-band translators 12 has been detected as being inactive for the pre-determined period of time.", "In a next step 202, the associated transmit DSP 48 is requested to send initiate loop back ping signal.", "The following step 204 causes the processor 50 to enter a wait state for a pre-determined time frame, after which in step 206 DSP 44 is asked to send the RACCH burst signals.", "In the next step 208, a timer is started with step 208 preferably occurring concurrently with step 206.", "In step 210, the return RACCH bursts are reported as being detected by the associated receiving DSP 44.", "In step 212, the timer data is read.", "In step 214, the terminate loop back ping signal is transmitted back to the in-band translator 12.", "In the final step 218 the offset time "t"", "is calculated by averaging the results of the repeated timing interval measurements and dividing by two.", "The process is repeated for each of the translators in the cluster 24 to determine a time interval measurement for each.", "FIG. 6 illustrates a sequence of steps performed by a receive DSP 44 during normal operation in connection with the invention.", "In a first step 220, the channel samples are read as in the normal demodulation processes as previously described.", "In a next step 222, the channel sample timing references are offset by the time "t"", "as determined from the process for the associated translator 12, as previously described in FIG. 5. In the next step 224, the channel samples are then further processed as for normal Time Division Multiple Access (TDMA) demodulation.", "It is now understood how the invention is able to compensate for the propagation delay between the in-band translator 12 and the host BTS 15.", "Computer simulations of an implementation of the invention has been shown that with a single host BTS 15 and twelve cells 22, coverage can be provided of approximately 1000 square kilometers by a single BTS 15 which would previously have been limited to a radius of 35 kilometers.", "This is accomplished by determining a fixed timing offset parameter for each in-band translator, by setting the in-band translator into a loop back mode via a transmission of a special loop back signal, transmitting an access burst as would normally be sent by a mobile unit, measuring the time of arrival delay at the BTS, and then using this measured time of arrival delay to determine an offset to be used to adjust the normal mode TDMA-demodulation processing." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin sealing method and apparatus of effecting resin sealing after the pad of a semiconductor chip mounted on a substrate is joined to the electrode of the substrate through a bump. Particularly, the present invention relates to a resin sealing method and apparatus filling the gap between a semiconductor chip and a substrate with resin. 2. Description of the Background Art In a semiconductor device having the pad of the semiconductor chip and the electrode of the substrate electrically connected via a bump, resin is inserted or filled into the gap between the semiconductor chip and the substrate and is then cured. This resin sealing is carried out in order to prevent generation of cracks at the junction due to thermal stress, and intrusion of a substance that adversely affects the semiconductor chip such as intrusion of impurities and moisture. Conventionally, the method shown in FIGS. 5A-5D is employed in order to insert and cure resin in the gap between a semiconductor chip and a substrate. FIGS. 5A-5D are plan views of a semiconductor device corresponding to respective steps of a conventional resin sealing method. Referring to FIG. 5A, liquid resin 102 is applied around a semiconductor chip 101 mounted on a substrate 100 so as to substantially surround the circumference thereof. A portion of the circumference of semiconductor chip 101 that is to serve as an outlet 103 is left absent of liquid resin 102 . Referring to FIG. 5B, the atmosphere around substrate 100 is reduced in pressure. Accordingly, the air present between substrate 100 and semiconductor chip 101 is output from outlet 103 as exhaust 104 . Referring to FIG. 5C, the viscosity of the applied liquid resin 102 is reduced by applying heat under the state where the atmosphere around substrate 100 is reduced in pressure. As a result, liquid resin 102 reduced in viscosity flows into the gap between substrate 100 and semiconductor chip 100 by the capillary action to be connected at the portion absent of the resin to become annular. Thus, the gap between substrate 100 and semiconductor chip 101 is filled with liquid resin 102 leaving a closed cavity 105 that is reduced in pressure. Referring to FIG. 5D, the atmosphere around substrate. 100 is pressurized up to the atmospheric pressure. Under atmospheric pressure, closed cavity 105 in the gap between substrate 100 and semiconductor chip 101 is compressed by the pressure difference from the surrounding space to be eliminated. In other words, the entire region of the gap between substrate 100 and semiconductor chip 100 is filled with liquid resin 102 . Then, heating is applied to cure liquid resin 102 . By the foregoing steps, cured seal resin is formed at the gap between substrate 100 and semiconductor chip 100 , and also at the circumference of semiconductor chip 101 . The conventional resin sealing method poses the following problems shown in FIGS. 6A-6D. FIGS. 6A-6D are plan views of a semiconductor device corresponding to respective steps of a conventional resin sealing method representing the problems. Referring to FIG. 6A, liquid resin 102 is applied on substrate 100 , likewise FIG. 5 A. In reducing the pressure of the atmosphere around substrate 100 , there is the case where abnormal exhaust 106 penetrates through liquid resin 102 to be output from a region other than outlet 103 due to uneven application of liquid resin 102 , as shown in FIG. 6 B. Also, in pressurizing the atmosphere around substrate 100 , there is the case where liquid resin 102 compressed towards closed cavity 105 by the pressure difference from the surrounding space is partially concentrated at the corner of semiconductor chip 101 to rise over the top surface of semiconductor chip 101 . There is also the case where abnormal exhaust 106 is output from substantially the entire circumference of semiconductor chip 101 when the area of the cross section of outlet 103 is not large enough. In the foregoing cases, a portion of liquid resin 102 will be blown off by the abnormal exhaust 106 to adhere on the top surface of semiconductor chip 101 as shown in FIG. 6 C. The adhered liquid resin 102 will remain on the top surface of semiconductor substrate 101 as resin covering 107 . This resin covering 107 is cured by the heating process as shown in FIG. 6D to cause appearance defect in the completed semiconductor device to degrade the yield. SUMMARY OF THE INVENTION In view of the foregoing, an object of the present invention is to provide a resin sealing method and apparatus to improve the yield by preventing generation of a resin covering in filling the gap between a substrate and a semiconductor chip with resin. According to an aspect of the present invention, a resin sealing method achieving the above object has resin inserted and cured in the gap formed between a substrate and a semiconductor chip mounted on the substrate. The resin sealing method includes the steps of applying resin of a predetermined amount, which is set corresponding to the circumferential configuration of the semiconductor chip, at or along the circumference of the semiconductor chip under a state retaining a predetermined void or space between the resin and a side face of the semiconductor chip, reducing the pressure of the atmosphere around the substrate to exhaust air from the gap, reducing the viscosity of the applied resin to partially fill the gap with resin and thereby leaving a closed cavity reduced in pressure, and pressurizing the atmosphere around the substrate to compress the closed cavity from the surrounding atmosphere due to the pressure difference therebetween to entirely fill the gap with resin. According to this resin sealing method, resin of a predetermined amount is applied at or along the circumference of the semiconductor chip in such a manner so as to retain a void or space between the resin and the side face of the semiconductor chip. Accordingly, a region absent of resin is formed surrounding the semiconductor chip at the substrate plane. By reducing the pressure of the atmosphere around the substrate, the air present between the substrate and the semiconductor chip is exhausted through the region where resin is not applied, i.e. through the gap or space formed between the resin applied at the circumferential position of the semiconductor chip and the side face of the semiconductor chip. Since this resin-free space forms a region where air can be exhausted having a large area of cross, section at the circumference of the semiconductor chip, exhaust can be effected stably. At the corner of the semiconductor chip, the amount of resin to be applied is reduced or a region absent of applying resin is provided. As a result, exhaust can be effected in stability at the corner region where exhaust is concentrated so that the exhaust pressure is increased. Thus, there is the advantage superior in practical usage of providing a resin sealing method and apparatus that can prevent generation of a resin covering caused by abnormal exhaust and resin concentration. In the above resin sealing method, the step of applying resin preferably has the amount of resin applied at the circumferential position of the site where the circumferential configuration of the semiconductor chip corresponds to a corner set lower than the amount of resin applied at the circumferential position of other sites of the semiconductor chip. In a preferable embodiment of the resin sealing method of the present invention, the step of applying resin includes the step of applying resin of a predetermined amount at the circumferential position of the semiconductor chip excluding the site where the circumferential configuration of the semiconductor chip corresponds to a corner. According to another aspect of the present invention, a resin sealing method of inserting and curing resin in a gap formed between a substrate and a semiconductor chip mounted on the substrate includes the steps of applying resin of a predetermined amount, which is set corresponding to the circumferential configuration of the semiconductor chip, at or along the circumference of the semiconductor chip in contact with a portion of the side face of the semiconductor chip at one region and retaining a predetermined void or space between the resin and another region of the side face, reducing the pressure of the atmosphere around the substrate to exhaust air from the gap, reducing the viscosity of the applied resin to partially fill the gap with resin and thereby leaving a closed cavity reduced in pressure, and pressurizing the atmosphere around the substrate to compress the closed cavity from the surrounding atmosphere due to the pressure difference therebetween to entirely fill the gap with resin. In a preferable embodiment of the resin sealing method of the present invention, the step of exhausting includes the step of reducing the pressure of the atmosphere around the substrate from the atmospheric pressure down to a predetermined pressure over a predetermined period of time. The resin sealing apparatus of the present invention fills a gap formed between a substrate and a semiconductor chip mounted on the substrate with resin. The resin sealing apparatus includes an application unit applying resin of a predetermined amount, which is set corresponding to the circumferential configuration of the semiconductor chip, at the circumference of the semiconductor chip in a manner retaining a predetermined void or space between the resin and the side face of the semiconductor chip, a pressure reduction unit to reduce the pressure of the atmosphere around the substrate to exhaust air from the gap, a viscosity reduction unit reducing the viscosity of the applied resin to partially fill the gap with resin leaving a closed cavity reduced in pressure, and a pressurization unit pressurizing the atmosphere around the substrate to compress the closed cavity from the surrounding atmosphere due to the pressure difference therebetween to entirely fill the gap with resin. According to this resin sealing apparatus, resin of a predetermined amount is applied at the circumferential position of the semiconductor chip under a state retaining a void or space relative to the side face of the semiconductor chip. Accordingly, a region absent of resin is formed at the substrate plane, surrounding the circumference of the semiconductor chip. When the atmosphere around the substrate is reduced in pressure, the air present in the gap between the substrate and the semiconductor chip is exhausted through the region where resin is not applied, i.e. through the space formed between the resin applied at the circumferential position of the semiconductor chip and the side face of the semiconductor chip. Since the region from which air is exhausted is formed to have a large area of cross section at the circumference of the semiconductor chip, exhaust can be effected stably. In a preferable embodiment of the resin sealing apparatus of the present invention, the atmosphere around the substrate is reduced in pressure from the atmospheric pressure down to a predetermined pressure over a predetermined period of time by the pressure reduction unit of the resin sealing apparatus. The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a semiconductor device fabricated according to a resin sealing method and resin sealing apparatus of the present invention. FIG. 2A is a plan view of a semiconductor device during a fabrication step employing the resin sealing method of the present invention; FIG. 2B is a sectional view taken along line II B -II B of FIG. 2A; and FIGS. 2C and 2D are sectional views of the semiconductor device at respective fabrication steps. FIGS. 3A and 3B are plan views of a semiconductor device during a fabrication step employing a modification of the resin sealing method of the present invention. FIG. 4 is a diagram to describe the relationship between exhaust time t and air pressure P as to exhaust in the resin sealing method of the present invention. FIGS. 5A-5D are plan views of a semiconductor device at respective steps corresponding to a conventional resin sealing method. FIGS. 6A-6D are plan views of a semiconductor device at respective steps indicating problems encountered in the conventional resin sealing method. FIG. 7 schematically shows a structure of a resin sealing apparatus of the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described hereinafter with reference to the drawings. The semiconductor device of FIG. 1 includes a semiconductor chip 1 where semiconductor elements are formed, a pad 2 which is an electrode of semiconductor chip 1 , a substrate 3 formed of, for example ceramic or organic material, an electrode 4 A for connection with substrate 3 , an external electrode 4 B of substrate 3 , a bump 5 formed of solder, for example, and resin 6 covering at least a portion of the side face of semiconductor chip 1 and filled in the gap between semiconductor chip 1 and substrate 3 . As shown in FIG. 1, pad 2 of semiconductor chip 1 and electrode 4 A of substrate 3 are electrically connected by bump 5 . A gap of 20-200 μm, for example, is formed between semiconductor chip 1 and substrate 3 . This gap is filled with resin 6 such as epoxy resin which is then cured. This resin 6 covers pad 2 , connection electrode 4 A and bump 5 to prevent exposure thereof, and allows semiconductor chip 1 and substrate 3 to be fixed so as to absorb any difference in thermal stress therebetween. An embodiment of the resin sealing method of the present invention will be described with reference to FIGS. 2A-2D. Respective steps carried out in fabricating the semiconductor device of FIG. 1 before the resin sealing method of the present invention is employed will be first described. Bump 5 formed of solder, for example, is provided on pad 2 of semiconductor chip 1 . Semiconductor chip 1 is turned over, and positioning of pad 2 and connection electrode 4 A of substrate 3 is effected. Then, substrate 3 is mounted with semiconductor chip 1 . Bump 5 is heated to melt, whereby pad 2 of semiconductor chip 1 is electrically connected to connection electrode 4 A of substrate 3 . According to the resin sealing method of the present invention, resin 6 is to be inserted or filled into the gap between semiconductor chip 1 and substrate 3 and is thereafter to be cured. As shown in FIGS. 2A and 2B, liquid resin 6 such as epoxy resin is applied to completely surround the circumference of semiconductor chip 1 with an exposed portion or predetermined space 7 above substrate 3 , between the resin 6 and the side face 1 A of the chip 1 . In other words, resin 6 is applied at the circumferential position of semiconductor chip 1 with a predetermined void or space 7 relative to the side face of semiconductor chip 1 . Then, the atmosphere around substrate 3 is reduced in pressure. Accordingly, the air present in gap 8 between the semiconductor chip 1 and substrate 3 is discharged as exhaust 9 passing above exposed portion 7 , i.e. out through the predetermined space surrounding semiconductor chip 1 . As shown in FIG. 2C, viscosity of the applied liquid resin 6 is reduced by applying heat, for example, under the state where the atmosphere around substrate 3 is reduced in pressure. Accordingly, resin 6 reduced in viscosity comes into contact with the side face and bottom face of semiconductor chip 1 , and further intrudes into gap 8 between substrate 3 and semiconductor chip 1 by the capillary action. Thus, gap 18 is filled with liquid resin 6 leaving a closed cavity 10 reduced in pressure. As shown in FIG. 2D, the atmosphere around substrate 3 is pressurized to a predetermined pressure, for example, to the atmospheric pressure. Accordingly, closed cavity 10 reduced in pressure in gap 8 between substrate 3 and semiconductor chip 1 is compressed by the pressure difference from the ambient air to be eliminated under atmospheric pressure. As a result, gap 8 is completely filled with resin 6 . Then, a heating step is applied to cure liquid resin 6 . By the foregoing steps, cured seal resin is formed at gap 8 between substrate 3 and semiconductor chip; and also at the circumference of semiconductor chip 1 . Pressurization of the atmosphere around substrate 3 can be effected by using, for example, a valve provided in the exhaust path and releasing the atmosphere to the open air. According to the resin sealing method of the present embodiment, liquid resin is applied with an exposed portion 7 provided above substrate 3 completely surrounding semiconductor chip 1 . When the atmosphere around substrate 3 is to be reduced in pressure, the air present in gap 8 between semiconductor chip 1 and substrate 3 is discharged as exhaust 9 passing above exposed portion 7 completely surrounding semiconductor chip 1 . By providing an exhaust path of exhaust 9 surrounding semiconductor chip 1 and having a large area of cross section of the exhaust path, exhaust 9 can be discharged in stability. Thus, generation of a resin covering can be prevented. The modifications shown in FIGS. 3A and 3B aim for stabilizing exhaust at the lower area of each corner of semiconductor chip 1 , i.e. below the four corners when viewed in plane, in discharging the air present at the gap between semiconductor chip 1 and substrate 3 . According to the modification of the resin sealing method of the present invention shown in FIG. 3A, liquid resin 6 is applied completely surrounding semiconductor chip 1 with exposed portion 7 provided above substrate 3 , as in the above-described embodiment. A particular region 11 is provided in the proximity of each corner of semiconductor chip 1 where the amount of resin applied is less than that of other regions. According to another modification of the resin sealing method of the present invention shown in FIG. 3B, resin 6 is applied to surround semiconductor chip 1 with exposed portion 7 above substrate 3 . Furthermore, a particular region 12 absent of resin 6 is provided in the proximity of each corner of semiconductor chip 1 . According to the above two modifications, resin 6 compressed towards the closed cavity due to pressure difference from the ambient space during pressurization of the atmosphere around substrate 3 will not be concentrated at the corner of semiconductor chip 1 , i.e. not blocked in flow. As a result, rise of resin 6 over the top surface of semiconductor chip 1 at the corner of semiconductor chip 1 is suppressed. The air present in the gap between semiconductor chip 1 and substrate 3 can be exhausted in stability from the entire circumference of semiconductor chip 1 , as in the above embodiment. Also, the rise of resin 6 at the corner of semiconductor chip 1 can be suppressed when the atmosphere around substrate 3 is pressurized. Thus, generation of a resin covering can be reliably prevented. Referring to FIG. 4, Patm is the atmospheric pressure and takes the value of 900-1060 hPa whereas the achievable pressure PL is the pressure around the substrate after the pressure-reduction step. As shown in FIG. 4, the atmosphere around the substrate is gradually reduced to achievable pressure PL over a period of time in order to prevent generation of a resin covering. With achievable pressure PL set to 20 Pa, for example, the pressure is reduced from atmospheric pressure Patm down to achievable pressure PL (=20 Pa) over a period of 5 seconds starting from pressure-reduction start time T 1 to pressure-reduction end time T 3 . In order to reliably prevent generation of a resin covering, the pressure is reduced from atmospheric pressure Patm down to achievable pressure PL (=20 Pa) over a period of 7-10 seconds, for example. The resin is then heated to have the viscosity reduced under the pressure-reduced state. Then, pressure is applied up to a predetermined pressure, for example, up to atmospheric pressure Patm. The pressure can be reduced gradually from pressure-reduction start time T 1 to a predetermined time T 2 , and then the pressure can be reduced rapidly from time T 2 to pressure-reduction end time T 3 , as shown in FIG. 4 . Furthermore, the pressure can be reduced continuously as shown by the broken line in FIG. 4 . Since exhaust is gradually effected from the high pressure state to lower the pressure, followed by rapid exhaust, the discharge operation can be effected more stably to reliably prevent generation of a resin covering. Resin covering can be reliably prevented by the combination of the exhaust of FIG. 4 with the application of resin shown in FIGS. 2A-3B. The resin sealing apparatus of the present invention will be described with reference to FIG. 7 . The resin sealing apparatus includes a stage on which is arranged a carrying body such as a tray 21 which carries thereon the substrate 3 with the semiconductor chip 1 attached thereon, a syringe (not shown) storing liquid resin, a dispenser nozzle 23 to emit resin by air pressure or the like, a heating stage 24 for heating the substrate 3 , a mechanism (not shown) for moving the tray 21 for supplying the substrate 3 having the resin applied thereon, to the heating stage 24 and taking out the substrate 3 from the heating stage 24 , a hermetic vessel 25 to seal up the substrate 3 supplied to the heating stage 24 , tubes 26 a, 26 b adapted for pressuring or reducing pressure from the interior of hermetic vessel 25 , flow rate adjust valves 28 a, 28 b provided respectively in the passage of tubes 26 a, 26 b, and a vacuum pump 29 functioning through tube 26 a. One end of tube 26 b is opened to the atmosphere and the inner pressure of hermetic vessel 25 is returned to the atmospheric pressure by opening flow rate adjust valve 28 b. Dispenser nozzle 23 is mounted to a XYZ robot 27 together with a camera 31 for image recognition used for adjusting the positional relation between the tip of the dispenser nozzle 23 and the substrate 3 . Vacuum pump 29 reduces the pressure of the interior of the hermetic vessel 25 . Compressor 30 is optionally connected to the tube 26 b for pressurizing the interior of hermetic vessel 25 . Using this resin sealing apparatus, resin is emitted from the dispenser nozzle 23 at an appropriate timing while moving the dispenser nozzle 23 by means of the XYZ robot 27 . Accordingly, liquid resin is applied on the substrate 3 as shown in FIGS. 2A-3B. After a shutter 32 attached to hermetic vessel 25 is opened, the carrying body 21 with the substrate 3 having the resin applied thereto being carried thereon, is introduced into hermetic vessel 25 along guide rails 30 a, 30 b through the mechanism for supplying substrate 3 . Then, shutter 32 is closed and exhaust shown in FIG. 4 is effected by means of the flow rate adjust valve 28 a and the vacuum pump 29 . The resin is heated by the heating stage 24 through the substrate 3 , whereby the viscosity of the resin is reduced. The interior of hermetic vessel 25 is pressurized to a predetermined pressure, for example the atmospheric pressure, by means of flow rate adjust valve 28 b. Then, resin is further heated by heating stage 24 to be cured. By the foregoing operation, the semiconductor device shown in FIG. 1 can be fabricated using the resin sealing apparatus of the present invention. The resin sealing apparatus of the present invention is not limited to the above-described structure. The usage of flow rate adjust valve 28 a, 28 b and vacuum pump 29 in reducing or applying pressure is only a way of example. Also, other heating means such as an infrared lamp can be used instead of heating stage 24 . The embodiments are described in which epoxy resin is used as resin. However, thermosetting resin such as silicone resin, vinyl polymerization resin, phenol resin, unsaturated polyester resin, diallyl phthalate resin, or super engineering plastic such as PPS and aromatic polyamide, general-purpose engineering plastic such as nylon resin and ultrahigh molecular weight polyethylene, or thermal plastic resin such as thermoplastic elastomer using olefin or amide can be also used. The bump is not limited to that formed of solder, and may be formed of Au, Ag/Sn and the like, or another conductive material such as conductive resin. Although exposed portion 7 is provided completely surrounding the circumference of semiconductor chip 1 in the above embodiments, resin can be applied to come into contact with a portion of the side face of semiconductor chip 1 as long as a resin covering is not generated. Accordingly, resin can flow smoothly downwards of semiconductor chip 1 from the region in contact with the side face of semiconductor chip 1 under the state where the viscosity of resin is reduced. As to the predetermined pressure, pressure is reduced down to 20 Pa and pressurized up to the atmospheric pressure in the above embodiments. However, the pressure can be reduced to less than 20 Pa or higher than 20 Pa. Also, the pressure can be increased up to below the atmospheric pressure or higher than the atmospheric pressure. Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims.
A resin sealing method for sealing a gap between a substrate and a semiconductor chip mounted thereon includes the following steps: applying a predetermined amount of resin at and along the circumference of the semiconductor chip in such a manner so as to maintain a space between the resin and a side face of the semiconductor chip; reducing the pressure of the atmosphere around the substrate to exhaust air from the gap; reducing the viscosity of the applied resin to partially fill the gap with resin, thereby leaving a closed cavity reduced in pressure; pressurizing the atmosphere around the substrate to compress the closed cavity due to the pressure difference from the surrounding atmosphere to entirely fill the gap with resin. The exhausting of the air is very stable, and a concentration of resin at the corner of the semiconductor chip can be suppressed, thereby avoiding the spattering of resin onto the top of the chip.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to a resin sealing method and apparatus of effecting resin sealing after the pad of a semiconductor chip mounted on a substrate is joined to the electrode of the substrate through a bump.", "Particularly, the present invention relates to a resin sealing method and apparatus filling the gap between a semiconductor chip and a substrate with resin.", "Description of the Background Art In a semiconductor device having the pad of the semiconductor chip and the electrode of the substrate electrically connected via a bump, resin is inserted or filled into the gap between the semiconductor chip and the substrate and is then cured.", "This resin sealing is carried out in order to prevent generation of cracks at the junction due to thermal stress, and intrusion of a substance that adversely affects the semiconductor chip such as intrusion of impurities and moisture.", "Conventionally, the method shown in FIGS. 5A-5D is employed in order to insert and cure resin in the gap between a semiconductor chip and a substrate.", "FIGS. 5A-5D are plan views of a semiconductor device corresponding to respective steps of a conventional resin sealing method.", "Referring to FIG. 5A, liquid resin 102 is applied around a semiconductor chip 101 mounted on a substrate 100 so as to substantially surround the circumference thereof.", "A portion of the circumference of semiconductor chip 101 that is to serve as an outlet 103 is left absent of liquid resin 102 .", "Referring to FIG. 5B, the atmosphere around substrate 100 is reduced in pressure.", "Accordingly, the air present between substrate 100 and semiconductor chip 101 is output from outlet 103 as exhaust 104 .", "Referring to FIG. 5C, the viscosity of the applied liquid resin 102 is reduced by applying heat under the state where the atmosphere around substrate 100 is reduced in pressure.", "As a result, liquid resin 102 reduced in viscosity flows into the gap between substrate 100 and semiconductor chip 100 by the capillary action to be connected at the portion absent of the resin to become annular.", "Thus, the gap between substrate 100 and semiconductor chip 101 is filled with liquid resin 102 leaving a closed cavity 105 that is reduced in pressure.", "Referring to FIG. 5D, the atmosphere around substrate.", "100 is pressurized up to the atmospheric pressure.", "Under atmospheric pressure, closed cavity 105 in the gap between substrate 100 and semiconductor chip 101 is compressed by the pressure difference from the surrounding space to be eliminated.", "In other words, the entire region of the gap between substrate 100 and semiconductor chip 100 is filled with liquid resin 102 .", "Then, heating is applied to cure liquid resin 102 .", "By the foregoing steps, cured seal resin is formed at the gap between substrate 100 and semiconductor chip 100 , and also at the circumference of semiconductor chip 101 .", "The conventional resin sealing method poses the following problems shown in FIGS. 6A-6D.", "FIGS. 6A-6D are plan views of a semiconductor device corresponding to respective steps of a conventional resin sealing method representing the problems.", "Referring to FIG. 6A, liquid resin 102 is applied on substrate 100 , likewise FIG. 5 A. In reducing the pressure of the atmosphere around substrate 100 , there is the case where abnormal exhaust 106 penetrates through liquid resin 102 to be output from a region other than outlet 103 due to uneven application of liquid resin 102 , as shown in FIG. 6 B. Also, in pressurizing the atmosphere around substrate 100 , there is the case where liquid resin 102 compressed towards closed cavity 105 by the pressure difference from the surrounding space is partially concentrated at the corner of semiconductor chip 101 to rise over the top surface of semiconductor chip 101 .", "There is also the case where abnormal exhaust 106 is output from substantially the entire circumference of semiconductor chip 101 when the area of the cross section of outlet 103 is not large enough.", "In the foregoing cases, a portion of liquid resin 102 will be blown off by the abnormal exhaust 106 to adhere on the top surface of semiconductor chip 101 as shown in FIG. 6 C. The adhered liquid resin 102 will remain on the top surface of semiconductor substrate 101 as resin covering 107 .", "This resin covering 107 is cured by the heating process as shown in FIG. 6D to cause appearance defect in the completed semiconductor device to degrade the yield.", "SUMMARY OF THE INVENTION In view of the foregoing, an object of the present invention is to provide a resin sealing method and apparatus to improve the yield by preventing generation of a resin covering in filling the gap between a substrate and a semiconductor chip with resin.", "According to an aspect of the present invention, a resin sealing method achieving the above object has resin inserted and cured in the gap formed between a substrate and a semiconductor chip mounted on the substrate.", "The resin sealing method includes the steps of applying resin of a predetermined amount, which is set corresponding to the circumferential configuration of the semiconductor chip, at or along the circumference of the semiconductor chip under a state retaining a predetermined void or space between the resin and a side face of the semiconductor chip, reducing the pressure of the atmosphere around the substrate to exhaust air from the gap, reducing the viscosity of the applied resin to partially fill the gap with resin and thereby leaving a closed cavity reduced in pressure, and pressurizing the atmosphere around the substrate to compress the closed cavity from the surrounding atmosphere due to the pressure difference therebetween to entirely fill the gap with resin.", "According to this resin sealing method, resin of a predetermined amount is applied at or along the circumference of the semiconductor chip in such a manner so as to retain a void or space between the resin and the side face of the semiconductor chip.", "Accordingly, a region absent of resin is formed surrounding the semiconductor chip at the substrate plane.", "By reducing the pressure of the atmosphere around the substrate, the air present between the substrate and the semiconductor chip is exhausted through the region where resin is not applied, i.e. through the gap or space formed between the resin applied at the circumferential position of the semiconductor chip and the side face of the semiconductor chip.", "Since this resin-free space forms a region where air can be exhausted having a large area of cross, section at the circumference of the semiconductor chip, exhaust can be effected stably.", "At the corner of the semiconductor chip, the amount of resin to be applied is reduced or a region absent of applying resin is provided.", "As a result, exhaust can be effected in stability at the corner region where exhaust is concentrated so that the exhaust pressure is increased.", "Thus, there is the advantage superior in practical usage of providing a resin sealing method and apparatus that can prevent generation of a resin covering caused by abnormal exhaust and resin concentration.", "In the above resin sealing method, the step of applying resin preferably has the amount of resin applied at the circumferential position of the site where the circumferential configuration of the semiconductor chip corresponds to a corner set lower than the amount of resin applied at the circumferential position of other sites of the semiconductor chip.", "In a preferable embodiment of the resin sealing method of the present invention, the step of applying resin includes the step of applying resin of a predetermined amount at the circumferential position of the semiconductor chip excluding the site where the circumferential configuration of the semiconductor chip corresponds to a corner.", "According to another aspect of the present invention, a resin sealing method of inserting and curing resin in a gap formed between a substrate and a semiconductor chip mounted on the substrate includes the steps of applying resin of a predetermined amount, which is set corresponding to the circumferential configuration of the semiconductor chip, at or along the circumference of the semiconductor chip in contact with a portion of the side face of the semiconductor chip at one region and retaining a predetermined void or space between the resin and another region of the side face, reducing the pressure of the atmosphere around the substrate to exhaust air from the gap, reducing the viscosity of the applied resin to partially fill the gap with resin and thereby leaving a closed cavity reduced in pressure, and pressurizing the atmosphere around the substrate to compress the closed cavity from the surrounding atmosphere due to the pressure difference therebetween to entirely fill the gap with resin.", "In a preferable embodiment of the resin sealing method of the present invention, the step of exhausting includes the step of reducing the pressure of the atmosphere around the substrate from the atmospheric pressure down to a predetermined pressure over a predetermined period of time.", "The resin sealing apparatus of the present invention fills a gap formed between a substrate and a semiconductor chip mounted on the substrate with resin.", "The resin sealing apparatus includes an application unit applying resin of a predetermined amount, which is set corresponding to the circumferential configuration of the semiconductor chip, at the circumference of the semiconductor chip in a manner retaining a predetermined void or space between the resin and the side face of the semiconductor chip, a pressure reduction unit to reduce the pressure of the atmosphere around the substrate to exhaust air from the gap, a viscosity reduction unit reducing the viscosity of the applied resin to partially fill the gap with resin leaving a closed cavity reduced in pressure, and a pressurization unit pressurizing the atmosphere around the substrate to compress the closed cavity from the surrounding atmosphere due to the pressure difference therebetween to entirely fill the gap with resin.", "According to this resin sealing apparatus, resin of a predetermined amount is applied at the circumferential position of the semiconductor chip under a state retaining a void or space relative to the side face of the semiconductor chip.", "Accordingly, a region absent of resin is formed at the substrate plane, surrounding the circumference of the semiconductor chip.", "When the atmosphere around the substrate is reduced in pressure, the air present in the gap between the substrate and the semiconductor chip is exhausted through the region where resin is not applied, i.e. through the space formed between the resin applied at the circumferential position of the semiconductor chip and the side face of the semiconductor chip.", "Since the region from which air is exhausted is formed to have a large area of cross section at the circumference of the semiconductor chip, exhaust can be effected stably.", "In a preferable embodiment of the resin sealing apparatus of the present invention, the atmosphere around the substrate is reduced in pressure from the atmospheric pressure down to a predetermined pressure over a predetermined period of time by the pressure reduction unit of the resin sealing apparatus.", "The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a semiconductor device fabricated according to a resin sealing method and resin sealing apparatus of the present invention.", "FIG. 2A is a plan view of a semiconductor device during a fabrication step employing the resin sealing method of the present invention;", "FIG. 2B is a sectional view taken along line II B -II B of FIG. 2A;", "and FIGS. 2C and 2D are sectional views of the semiconductor device at respective fabrication steps.", "FIGS. 3A and 3B are plan views of a semiconductor device during a fabrication step employing a modification of the resin sealing method of the present invention.", "FIG. 4 is a diagram to describe the relationship between exhaust time t and air pressure P as to exhaust in the resin sealing method of the present invention.", "FIGS. 5A-5D are plan views of a semiconductor device at respective steps corresponding to a conventional resin sealing method.", "FIGS. 6A-6D are plan views of a semiconductor device at respective steps indicating problems encountered in the conventional resin sealing method.", "FIG. 7 schematically shows a structure of a resin sealing apparatus of the present invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described hereinafter with reference to the drawings.", "The semiconductor device of FIG. 1 includes a semiconductor chip 1 where semiconductor elements are formed, a pad 2 which is an electrode of semiconductor chip 1 , a substrate 3 formed of, for example ceramic or organic material, an electrode 4 A for connection with substrate 3 , an external electrode 4 B of substrate 3 , a bump 5 formed of solder, for example, and resin 6 covering at least a portion of the side face of semiconductor chip 1 and filled in the gap between semiconductor chip 1 and substrate 3 .", "As shown in FIG. 1, pad 2 of semiconductor chip 1 and electrode 4 A of substrate 3 are electrically connected by bump 5 .", "A gap of 20-200 μm, for example, is formed between semiconductor chip 1 and substrate 3 .", "This gap is filled with resin 6 such as epoxy resin which is then cured.", "This resin 6 covers pad 2 , connection electrode 4 A and bump 5 to prevent exposure thereof, and allows semiconductor chip 1 and substrate 3 to be fixed so as to absorb any difference in thermal stress therebetween.", "An embodiment of the resin sealing method of the present invention will be described with reference to FIGS. 2A-2D.", "Respective steps carried out in fabricating the semiconductor device of FIG. 1 before the resin sealing method of the present invention is employed will be first described.", "Bump 5 formed of solder, for example, is provided on pad 2 of semiconductor chip 1 .", "Semiconductor chip 1 is turned over, and positioning of pad 2 and connection electrode 4 A of substrate 3 is effected.", "Then, substrate 3 is mounted with semiconductor chip 1 .", "Bump 5 is heated to melt, whereby pad 2 of semiconductor chip 1 is electrically connected to connection electrode 4 A of substrate 3 .", "According to the resin sealing method of the present invention, resin 6 is to be inserted or filled into the gap between semiconductor chip 1 and substrate 3 and is thereafter to be cured.", "As shown in FIGS. 2A and 2B, liquid resin 6 such as epoxy resin is applied to completely surround the circumference of semiconductor chip 1 with an exposed portion or predetermined space 7 above substrate 3 , between the resin 6 and the side face 1 A of the chip 1 .", "In other words, resin 6 is applied at the circumferential position of semiconductor chip 1 with a predetermined void or space 7 relative to the side face of semiconductor chip 1 .", "Then, the atmosphere around substrate 3 is reduced in pressure.", "Accordingly, the air present in gap 8 between the semiconductor chip 1 and substrate 3 is discharged as exhaust 9 passing above exposed portion 7 , i.e. out through the predetermined space surrounding semiconductor chip 1 .", "As shown in FIG. 2C, viscosity of the applied liquid resin 6 is reduced by applying heat, for example, under the state where the atmosphere around substrate 3 is reduced in pressure.", "Accordingly, resin 6 reduced in viscosity comes into contact with the side face and bottom face of semiconductor chip 1 , and further intrudes into gap 8 between substrate 3 and semiconductor chip 1 by the capillary action.", "Thus, gap 18 is filled with liquid resin 6 leaving a closed cavity 10 reduced in pressure.", "As shown in FIG. 2D, the atmosphere around substrate 3 is pressurized to a predetermined pressure, for example, to the atmospheric pressure.", "Accordingly, closed cavity 10 reduced in pressure in gap 8 between substrate 3 and semiconductor chip 1 is compressed by the pressure difference from the ambient air to be eliminated under atmospheric pressure.", "As a result, gap 8 is completely filled with resin 6 .", "Then, a heating step is applied to cure liquid resin 6 .", "By the foregoing steps, cured seal resin is formed at gap 8 between substrate 3 and semiconductor chip;", "and also at the circumference of semiconductor chip 1 .", "Pressurization of the atmosphere around substrate 3 can be effected by using, for example, a valve provided in the exhaust path and releasing the atmosphere to the open air.", "According to the resin sealing method of the present embodiment, liquid resin is applied with an exposed portion 7 provided above substrate 3 completely surrounding semiconductor chip 1 .", "When the atmosphere around substrate 3 is to be reduced in pressure, the air present in gap 8 between semiconductor chip 1 and substrate 3 is discharged as exhaust 9 passing above exposed portion 7 completely surrounding semiconductor chip 1 .", "By providing an exhaust path of exhaust 9 surrounding semiconductor chip 1 and having a large area of cross section of the exhaust path, exhaust 9 can be discharged in stability.", "Thus, generation of a resin covering can be prevented.", "The modifications shown in FIGS. 3A and 3B aim for stabilizing exhaust at the lower area of each corner of semiconductor chip 1 , i.e. below the four corners when viewed in plane, in discharging the air present at the gap between semiconductor chip 1 and substrate 3 .", "According to the modification of the resin sealing method of the present invention shown in FIG. 3A, liquid resin 6 is applied completely surrounding semiconductor chip 1 with exposed portion 7 provided above substrate 3 , as in the above-described embodiment.", "A particular region 11 is provided in the proximity of each corner of semiconductor chip 1 where the amount of resin applied is less than that of other regions.", "According to another modification of the resin sealing method of the present invention shown in FIG. 3B, resin 6 is applied to surround semiconductor chip 1 with exposed portion 7 above substrate 3 .", "Furthermore, a particular region 12 absent of resin 6 is provided in the proximity of each corner of semiconductor chip 1 .", "According to the above two modifications, resin 6 compressed towards the closed cavity due to pressure difference from the ambient space during pressurization of the atmosphere around substrate 3 will not be concentrated at the corner of semiconductor chip 1 , i.e. not blocked in flow.", "As a result, rise of resin 6 over the top surface of semiconductor chip 1 at the corner of semiconductor chip 1 is suppressed.", "The air present in the gap between semiconductor chip 1 and substrate 3 can be exhausted in stability from the entire circumference of semiconductor chip 1 , as in the above embodiment.", "Also, the rise of resin 6 at the corner of semiconductor chip 1 can be suppressed when the atmosphere around substrate 3 is pressurized.", "Thus, generation of a resin covering can be reliably prevented.", "Referring to FIG. 4, Patm is the atmospheric pressure and takes the value of 900-1060 hPa whereas the achievable pressure PL is the pressure around the substrate after the pressure-reduction step.", "As shown in FIG. 4, the atmosphere around the substrate is gradually reduced to achievable pressure PL over a period of time in order to prevent generation of a resin covering.", "With achievable pressure PL set to 20 Pa, for example, the pressure is reduced from atmospheric pressure Patm down to achievable pressure PL (=20 Pa) over a period of 5 seconds starting from pressure-reduction start time T 1 to pressure-reduction end time T 3 .", "In order to reliably prevent generation of a resin covering, the pressure is reduced from atmospheric pressure Patm down to achievable pressure PL (=20 Pa) over a period of 7-10 seconds, for example.", "The resin is then heated to have the viscosity reduced under the pressure-reduced state.", "Then, pressure is applied up to a predetermined pressure, for example, up to atmospheric pressure Patm.", "The pressure can be reduced gradually from pressure-reduction start time T 1 to a predetermined time T 2 , and then the pressure can be reduced rapidly from time T 2 to pressure-reduction end time T 3 , as shown in FIG. 4 .", "Furthermore, the pressure can be reduced continuously as shown by the broken line in FIG. 4 .", "Since exhaust is gradually effected from the high pressure state to lower the pressure, followed by rapid exhaust, the discharge operation can be effected more stably to reliably prevent generation of a resin covering.", "Resin covering can be reliably prevented by the combination of the exhaust of FIG. 4 with the application of resin shown in FIGS. 2A-3B.", "The resin sealing apparatus of the present invention will be described with reference to FIG. 7 .", "The resin sealing apparatus includes a stage on which is arranged a carrying body such as a tray 21 which carries thereon the substrate 3 with the semiconductor chip 1 attached thereon, a syringe (not shown) storing liquid resin, a dispenser nozzle 23 to emit resin by air pressure or the like, a heating stage 24 for heating the substrate 3 , a mechanism (not shown) for moving the tray 21 for supplying the substrate 3 having the resin applied thereon, to the heating stage 24 and taking out the substrate 3 from the heating stage 24 , a hermetic vessel 25 to seal up the substrate 3 supplied to the heating stage 24 , tubes 26 a, 26 b adapted for pressuring or reducing pressure from the interior of hermetic vessel 25 , flow rate adjust valves 28 a, 28 b provided respectively in the passage of tubes 26 a, 26 b, and a vacuum pump 29 functioning through tube 26 a. One end of tube 26 b is opened to the atmosphere and the inner pressure of hermetic vessel 25 is returned to the atmospheric pressure by opening flow rate adjust valve 28 b. Dispenser nozzle 23 is mounted to a XYZ robot 27 together with a camera 31 for image recognition used for adjusting the positional relation between the tip of the dispenser nozzle 23 and the substrate 3 .", "Vacuum pump 29 reduces the pressure of the interior of the hermetic vessel 25 .", "Compressor 30 is optionally connected to the tube 26 b for pressurizing the interior of hermetic vessel 25 .", "Using this resin sealing apparatus, resin is emitted from the dispenser nozzle 23 at an appropriate timing while moving the dispenser nozzle 23 by means of the XYZ robot 27 .", "Accordingly, liquid resin is applied on the substrate 3 as shown in FIGS. 2A-3B.", "After a shutter 32 attached to hermetic vessel 25 is opened, the carrying body 21 with the substrate 3 having the resin applied thereto being carried thereon, is introduced into hermetic vessel 25 along guide rails 30 a, 30 b through the mechanism for supplying substrate 3 .", "Then, shutter 32 is closed and exhaust shown in FIG. 4 is effected by means of the flow rate adjust valve 28 a and the vacuum pump 29 .", "The resin is heated by the heating stage 24 through the substrate 3 , whereby the viscosity of the resin is reduced.", "The interior of hermetic vessel 25 is pressurized to a predetermined pressure, for example the atmospheric pressure, by means of flow rate adjust valve 28 b. Then, resin is further heated by heating stage 24 to be cured.", "By the foregoing operation, the semiconductor device shown in FIG. 1 can be fabricated using the resin sealing apparatus of the present invention.", "The resin sealing apparatus of the present invention is not limited to the above-described structure.", "The usage of flow rate adjust valve 28 a, 28 b and vacuum pump 29 in reducing or applying pressure is only a way of example.", "Also, other heating means such as an infrared lamp can be used instead of heating stage 24 .", "The embodiments are described in which epoxy resin is used as resin.", "However, thermosetting resin such as silicone resin, vinyl polymerization resin, phenol resin, unsaturated polyester resin, diallyl phthalate resin, or super engineering plastic such as PPS and aromatic polyamide, general-purpose engineering plastic such as nylon resin and ultrahigh molecular weight polyethylene, or thermal plastic resin such as thermoplastic elastomer using olefin or amide can be also used.", "The bump is not limited to that formed of solder, and may be formed of Au, Ag/Sn and the like, or another conductive material such as conductive resin.", "Although exposed portion 7 is provided completely surrounding the circumference of semiconductor chip 1 in the above embodiments, resin can be applied to come into contact with a portion of the side face of semiconductor chip 1 as long as a resin covering is not generated.", "Accordingly, resin can flow smoothly downwards of semiconductor chip 1 from the region in contact with the side face of semiconductor chip 1 under the state where the viscosity of resin is reduced.", "As to the predetermined pressure, pressure is reduced down to 20 Pa and pressurized up to the atmospheric pressure in the above embodiments.", "However, the pressure can be reduced to less than 20 Pa or higher than 20 Pa.", "Also, the pressure can be increased up to below the atmospheric pressure or higher than the atmospheric pressure.", "Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims." ]
This is a continuation application under 37 CFR 1.62 of prior application Ser. No. 07/452,065, filed Dec. 15, 1989, now abandoned. BACKGROUND OF THE INVENTION This invention relates to a method and apparatus for use with software programs and, in particular, to a method and apparatus for controlling operation and control block management of these programs. In computer operating systems in use today, the programs of the systems are often segmented into layers each of which contains a group of self-contained functions or procedures. Each such layer shall be referred to herein as a Layered Procedure Set or LPS. A basic model governing the communication of messages between and the invoking of LPSs in computer programs is the so-called queued "Scheduler-Dispatcher" model. This model is widely used in the data processing industry, especially in data communications. A particular data communications version of a Scheduler-Dispatcher model is described in Appendix C of IBM's SNA Format & Protocol Reference: Architectual Logic. In the queued Scheduler-Dispatcher functionality, message event blocks (MEBs) are used in conjunction with the Scheduler, Dispatcher and LPSs. MEBs provide an internal storage medium consistent enough in form to be able to pass messages identified as events and their associated control information from place to place within a program, and especially through the Scheduler and Dispatcher and between LPSs. In one version of the Scheduler-Dispatcher model, the Scheduler functions as a loop within a procedure. The Scheduler loop first waits on interrupts within the system and when an input/output ("I/O") procedure completes, identifies an associated MEB on its ready queue ("READY Q"), dequeues the MEB and enqueues it to the queue of the Dispatcher ("DISPATCH Q") and calls the Dispatcher. The Scheduler also acts on receiving control back from the Dispatcher to check its Ready Q and, if the READY Q contains an MEB, the Scheduler dequeues the MEB from the READY Q and enqueues it to the DISPATCH Q and calls the Dispatcher. If the READY Q is empty, however, the Scheduler checks the queue of the I/O ("I/O Q"). If there is an MEB on the I/O Q, the Scheduler dequeues the MEB and passes it as a parameter for execution of the I/O procedure. When the Dispatcher is called by the Scheduler, the Dispatcher dequeues an MEB from its DISPATCH Q and calls the LPS associated with the destination contained in the MEB, passing the MEB as a parameter. When control is returned to the dispatcher from the LPS, the Dispatcher checks the DISPATCH Q to determine whether any MEBs are present. If the DISPATCH Q is empty, it returns control to the Scheduler. If the DISPATCH Q is not empty, the Dispatcher repeats its procedure until the DISPATCH Q is empty at which time It then returns control to the Scheduler for repeat of the Scheduler procedure. In the above operation of the Scheduler-Dispatcher model, the Scheduler, if there are no MEBs in the READY Q, checks the I/O Q to determine whether there are any MEBs present in this queue. If so, the Scheduler dequeues the MEB from the I/O Q to initiate execution of an I/O procedure. This is accomplished by an I/O handler ("I/O Handler") which begins execution upon a call from the Scheduler. This call is accompanied by passing of the MEB. Once the I/O handler has initiated the I/O operation, it returns control immediately to the Scheduler. To complete an I/O, the Scheduler invokes the I/O Handler by a call to the procedure wait on interrupt. The I/O Handler then checks for completion interrupts for the I/O operation (e.g., hitting of a key by a user). If a completion interrupt has occurred, the I/O Handler locates the MEB associated with that I/O, updates the MEB and enqueues it to the READY Q. If a completion interrupt has not occurred, the I/O Handler suspends processing and the process is idle until a completion interrupt actually OCCURS. The call by the Scheduler to the wait on interrupt procedure is completed when the I/O Handler returns control to the Scheduler. At this point, the Scheduler falls through, i.e., returns to, its READY Q loop procedure. In particular, the Scheduler initiates the LPS portion of its processing cycle by dequeuing the completed and updated MEB from the I/O operation in its READY Q, enqueuing the EMB to the Dispatch Q and then calling the Dispatcher. The LPS structure and the Scheduler-Dispatcher model with I/O Handler and MEBs is of considerable use in controlling execution and operation and control block management and storage in programs. It is particularly advantageous where the level of complexity of a program is such as to require the utilization of multiple LPSs for the purpose of modularity. It is also advantageous where multiple sessions are to be executed concurrently within the same program. As used herein, a session within a program may be thought of as one or more multi-threaded tasks intended to be completed as a unit. This unit, however, will not be executed continuously from start to finish and the execution of units of several sessions may be occurring concurrently. As an example, the tasks associated with the operation of a single terminal may be considered as a session, while the tasks associated with the operation of multiple terminals may be considered as multiple sessions. A typical example of a program requiring the LPS and Scheduler-Dispatcher structure might be a data communications program (e.g., SNA or OSI) where there are formally architectured functional divisions of labor and where there are many devices (terminals, remote computer systems, disk resources) which are being serviced simultaneously. While the LPS structure is highly advantageous, the manner of storage and management of the control blocks, both MEBs and layer control blocks ("CBs") which store control and other information associated with the LPSs, permits programming which can have undesired results. A typical data structure for such storage and management of MEBs and CBs is described and shown on page 8 of Appendix A of the aforementioned IBM reference. As shown by the illustrated Node Control Block (equivalent to an MEB), all the CBs are attached directly to the Node Control Block, are rigidly set forth or typed, and all CBs of all the layers (the equivalent of LPSs) are freely available to any other layer. With this type of storage and management for the CBs, it becomes possible for one LPS to access and alter the content of the CB of another LPS. Such alteration, if it occurs, can have a detrimental effect on program operation, since the second LPS may need its unaltered CB in continuing a procedure. It also inhibits so-called "information hiding", which has been found to be beneficial to program operation and management. It is, therefore, an object of the present invention to provide a method and apparatus for program control and operation which tends to mitigate the aforesaid disadvantages. It is a further object of the present invention to provide a method and apparatus for program control in an LPS architectured system which is structured to establish privacy of each CB with respect to its LPS. It is a further object of the present invention to provide a method and apparatus for program control in an LPS architectured system wherein access of an LPS to a CB of another LPS is inhibited. It is yet a further object of the present invention to provide a method and apparatus for program control in an LPS architectured system wherein information hiding is promoted. SUMMARY OF THE INVENTION In accordance with the principles of the present invention, the above and other objectives are realized by configuring the program and program control of an LPS based system such that the MEBs established in the program for a particular session are associated only with that particular session. The program and control are further configured such that each LPS is allocated only a single CB for a particular session, which CB is only accessible by that LPS and not other LPSs during the session. In the embodiment of the invention to be disclosed hereinafter, an MEB established for a session carries an identifier (referred to as a SESSION KEY) which uniquely allocates the MEB to the session for which it was established. Similarly the CB of an LPS for a particular session, is associated with the SESSION KEY for that session, as well as with the identifier of the LPS (referred to as "LPSID") for which the CB was established. In this way, each established MEB is allocated to a particular session and each established CB is allocated to a particular LPS in a particular session. Furthermore, each LPS is constrained to invoke only a SESSION KEY and its LPSID when developing a pointer for a CB. As a result, an LPS is compelled to retrieve only its own CB and access to the CBs of other LPSs is inhibited. In further aspects of the invention, access to a particular LPS is confined to a single entry point (referred to as the Entry Router) and exit from the LPS to a particular exit point (referred to as the Exit Router) so as to prevent calling of procedures within an LPS directly from outside the LPS. Also the programming and CB storage control and management is such that the storage scheme for the CB of an LPS is unknown to the LPS. In addition, the programming inhibits the LPS from accessing sessions other than that of a current MEB. These requirements along with permitting an LPS to access only its own allocated CB in a session, facilitate the information hiding aspects of the system. BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and aspects of the present invention will become more apparent upon reading the following detailed description conjunction with the accompanying drawings, in which FIG. 1 illustrates a computing apparatus and associated terminals in accordance with the principles of the present invention; FIG. 2 shows the details of a portion of the program execution and control system of the apparatus of FIG. 1; FIG. 3 shows the structure of an MEB used in the program execution and control system of FIG. 2; FIG. 4 shows in greater detail an LPS used in the system of FIG. 1; FIGS. 5-7 show diagrammatically an example of the sequence of operation of the program of the apparatus of FIG. 1; and FIGS. 7-21 the program flow corresponding to the operating sequence of FIGS. 5-6. DETAILED DESCRIPTION FIG. 1 shows a computing apparatus or system 1 including a program execution and control operating system 2 for executing a program 3 comprised of a plurality of LPSs 3A, 3B . . . 3N and a program control means 3' which is described in greater detail hereinabelow. The apparatus 1 is addressed by a plurality of terminals 4A, 4B and communicates with a plurality of storage units or disks 5A, 5B. The computing apparatus 1 can be any type of computing apparatus with a processing environment similar to that of UNIX and a programming environment like that of C. Such computing apparatus can support the program 3 with LPSs 3A to 3N. For example, the computing apparatus might be an IBM PC with an MS-DOS operating system or a DEC VAX with a VMS operating system, or the environment on which the LPS program originated, Tandem NonStop with Guardian. The program 3 is a single program instantiated as a single running process. The terms process and program are intended to convey the equivalent of a UNIX program and process. In the present illustrative case, the program 3 is complex enough to be divided into functionally discrete groupings of functions or procedures which are multi-threaded in nature (i.e., several actions can be taken place concurrently). As above-indicated, each LPS 3A to 3N is an entirely self contained group of functions or procedures. Furthermore, in accordance with the invention, entry into and exit from each LPS 3A to 3N is through a single procedure. These attributes for each of the LPSs 3A to 3N are illustrated for the LPS 3A in FIG. 4. As shown, the LPS 3A contains procedures Proc 1 to Proc 3 and entry into the LPS 3A is through a single procedure, called only by the Dispatcher (described below), identified as Entrance Router; and exit is also through a single procedure, and identified as the Exit Router. By exit is meant the issuance of MEBs to other LPSs or the I/O Handler (described below). More particularly, a procedure in LPS 3A is indirectly invoked as a function of the input handling performed by the Entrance Router for that LPS. A procedure within an LPS 3A, on the other hand, cannot generate output, except by invoking the Exit Router for that LPS. FIG. 2 shows the program control means 3' which supports control of inputs and outputs in and to the program 3 and, in particular, in, to and between the LPSs 3A to 3N. This program control means 3' of the program 3 is in the form of the Scheduler-Dispatcher model and I/O Handler discussed above. Thus, as shown, in FIG. 2, the execution section 2A comprises a Scheduler 21, Dispatcher 22, I/O Handler 23, I/O Q 24, READY Q 25 and DISPATCH Q. These elements function as previously described above for the Scheduler-Dispatcher model in interacting with the LPSs 3A to 3N within the program 3. The program control means 3' also includes a Control Manager 27 which acts also as a secondary scheduler for the output MEBS from the LPSs 3A to 3N routing them to the I/O Q and the DISPATCH Q as determined by the outputs. FIG. 3 shows the structure of an MEB utilized in the program 3 and program control means 3' for conveying messages. As shown, the MEB includes usual fields marked ELEMENT, ORIGIN, DESTINATION, EVENT, DATA COUNT, DATA, and USER DATA. Of these, the fields DESTINATION and ORIGIN provide information as to the next element to be receiving the MEB (DESTINATION) and the element which last received the MEB and its associated message (ORIGIN). In the case of messages to and from an LPS, these fields would contain the identifier LPSID of the particular LPS. ELEMENT refers to any LPS or the I/O Handler. The fields DATA and DATA COUNT are pointers to a message buffer and the size of the buffer respectively. The field EVENT designates the event to be invoked by the MEB. In accordance with the principles of the present invention, the MEB is adapted to include a further field which specifically identifies the MEB with a particular session of the program 3. In the case shown, this field is identified as Session Key. The Session Key ties the MEB to a particular session. Recognizing the need for passing information between LPSs (normally accomplished by direct access of CBs by LPSs), a USER DATA pointer field is provided for the MEB and is constrained to contain only data specifically required for inter LPS communication. More general data concerning each LPS is thus not available from this field, thereby promoting hiding of the LPS data. An MEB is generated by the program 3 upon the establishment of each new session. The MEB is created by a procedure or function within the program 3 by calling the procedure CREATE MEB. The called procedure responds by creating an MEB having a SESSION KEY or pointer which identifies the session uniquely and the place in memory allocated to the session. The allocated memory location can then be accessed for later use by LPSs invoking specific procedures detailed hereinbelow passing the Session Key as a parameter. The creation of an MEB may likely be performed upon initialization of the program 3, as by one of the terminals 4A, 4B being brought into operation. Each initialization of a different terminal amounts to a new session and each new session establishes another MEB with a Session Key allocated to that session. Once an MEB with a Session Key has been established for a session, the LPSs 3A to 3N can duplicate the created MEB by calling the procedure CLONE MEB. This procedure creates a new MEB based on the original MEB passed with the call and the new MEB has the same SESSION KEY and identifier as the original MEB. Also, each LPS can destroy an existing MEB allocated to a session by calling the procedure PUT MEB. If the MEB is the only one allocated to the session, the session as well as the MEB will be terminated. As above-indicated, each of the LPSs is identified with an identifier LPSID which identifies it uniquely among the LPSs within a single program. In further accordance with the invention, the program 3 and control means 3' are such that each LPS is further allocated only a single CB and corresponding memory storage area for each program session. The CB is established by the LPS calling the procedure ALLOCATE CB which then allocates a CB using the LPSID of the LPS and the MEB SESSION KEY as unique identifiers. In allocating a CB, the length of the CB is determined by the LPS in the ALLOCATE CB instruction to insure complete flexibility in the CB format. The program 3 and control means 3' are also such that storage of an allocated CB of an LPS is unknown to the LPS until retrieval of a CB which can only be achieved by the LPS calling FIND CB with the LPSID and SESSION KEY. Likewise, a CB of an LPS can be removed from a session by calling DEALLOCATE CB again using only the combination of LPSID and SESSION KEY. Illustrative Examples, of procedures for CREATE MEB, CLONE MB, PUT MEB, ALLOCATE CB, FIND CB and DEALLOCATE CB are set forth in the attached Appendix I, pages A14-20, which is made a part hereof. By requiring that a LPS only have access to a CB in a session by calling its LPSID and the SESSION KEY, an LPS is given access only to its own CB. Thus, access to and altering of another LPS's CB is prevented. Furthermore, the programming 3 and control means 3' are such that each LPS can only access the session of the current MEB. These atributes of the LPSs foster information hiding in the program 3. FIGS. 5-7 show diagrammatically an example of the sequence of operation of the system 1 during initialization of the terminals 4A, 4B and during subsequent entry of inputs at the terminals, respectively. FIGS. 7-21 illustrate the program flow corresponding to the operating sequences of FIGS. 5-7. An example of a short program for performing the sequence of operation in FIGS. 5-7 is set forth in the aforementioned Appendix I, at pages A1-A13, with the steps in FIGS. 5-7 being indicated on the corresponding program parts. In the operating sequence of the above figures, it is assumed that both terminals 4A and 4B turn on requiring two sessions designated A and B which will operate concurrently. It is further assumed that during these sessions both terminals will specify events requiring procedures of LPSs 3A and 3B. Prior to initialization, the READY Q, DISPATCH Q and I/O Q are empty and there are no MEBs present. Upon initialization of the terminals 4A and 4B, program 3 invokes sequence steps 1 and 2 in which the program creates a first MEB(A) associated with the session A of the terminal 4A and a second MEB(B) associated with the session B of the terminal 4B. These MEBs are placed on the READY Q for processing by the Scheduler at step 3. The Scheduler dequeues the MEB(A) from the READY Q to the DISPATCH Q and calls the Dispatcher. At step 4, the Dispatcher dequeues the MEB(A) to the LPS 3A identified by the LPSID in the DESTINATION block of the MEB. In step 5, the LPS 3A processes the MEB(A) in accordance with the EVENT block which indicates initialization. LPS 3A thereupon allocates a CB to itself and identifies the CB with the MEB(A) SESSION KEY and with the LPSID of LPS 3A. The MEB(A) through the program manager is then placed on the I/O Q. That completes the Dispatch cycle for the MEB(A) and control returns to the Scheduler. In steps 6, 7, 8 and the steps 3, 4 and 5 are repeated for the MEB (B), resulting in a second CB for the LPS 3A being established for the session B, which CB is uniquely identified by the MEB<B) session Key and the LPSID of LPS 3A. Step 8 completes the second Dispatch cycle and both MEB(A) and MEB(B) are on the I/O Q. In step 9, the Scheduler finds no MEBs in its READY Q and thus falls through to the I/O Q which now contains MEB(A) and MEB(B). The Scheduler dequeues MEB(A) and calls for an I/O. The Scheduler then in step 10 again continues its loop on the I/0 Q, dequeues MEB(B) and calls for an I/O. In step 11, the Scheduler then waits for a completion interrupt for an I/O procedure. In the present case, it is assumed that the I/O for terminal 4B associated with the session B and MEB(B) completes first (e.g. user on terminal 4B hits enter key) causing a completion interrupt. The I/O Handler then places the MEB(B) on the READY Q with its DESTINATION set at its previous ORIGIN, i.e., LPS 3A and returns control to Scheduler. The MEB(A) is still in the I/O, since no completion interrupt for this MEB has occurred. In step 12 the Scheduler loops back to check the READY Q dequeues MEB(B) from the READY Q, enqueues it on the DISPATCH Q and calls the Dispatcher. In step 13, the DISPATCHER dequeues the DISPATCH Q, passing the MEB(B) to the LPS 3A, its DESTINATION. At this point, the MEB(A) still remains in the I/O. At step 14, the LPS 3A, recognizes from the EVENT of MEB(B) that the I/O for MEB(B) has been completed. It then calls its CB for the Session B, using the MEB(B) SESSION KEY and LPSID. After updating, the LPS 3A procedure continues, whereupon it is assumed that a query regarding the session B has been made to LPS 3A by the user. The LPS 3A thus changes the DESTINATION for the MEB(B) to LPS 3B and its event to data in to satisfy the query. The MEB(B) is then placed on the DISPATCH Q, while the MEB(A) still remains in the I/O. In step 15, the Dispatcher dequeues the DISPATCH Q passing the MEB(B) to the LPS 3B by calling this LPS. At step 16, the LPS 3B, recognizing this as a new session, establishes a CB for the new session B by calling the procedure ALLOCATE CB. The CB is then allocated using the MEB(B) SESSION KEY and the LPSID as identifiers. The LPS 3B then updates and its procedure continues, whereupon it calls for a disk I/O. The MEB(B) is then placed on the I/O Q with its EVENT changed to do disk The MEB(A) still remains in the I/O. Since there are no MEBs on the DISPATCH Q, this ends the dispatcher cycle. Return of control is thus made to the Scheduler in step 17. The Scheduler, finding nothing in its READY Q, then falls through to the I/O Q. The Scheduler finds MEB(B) in the I/O Q and dequeues MEB(B) calling for an I/O at step 17. At this point, internal processing is carried out, the I/O Handler returns control to the Scheduler, and the Scheduler waits for a completion interrupt for an I/O by calling the procedure wait on interrupt, since both MEB(A) and MEB(B) are in I/O. In step 18, the I/O for MEB(A) completes. The MEB(A) is placed by the I/O Handler on the READY Q with its DESTINATION LPS 3A and its EVENT changed to io done. Control is returned to the Scheduler. The Scheduler then calls the Dispatcher after the MEB(A) is dequeued from the READY Q and enqueued to the DISPATCH Q, while the MEB(B) remains in the I/O. In step 19, the Dispatcher dequeues the DISPATCH Q passing the MEB(A) to LPS 3A, the MEB(B) still remaining in the I/O. In step 20,the LPS 3A recognizes that the I/O has been completed and calls its CB for the session A with the MEB(A) SESSION KEY and LPSID. The Session A CB is updated and the procedure continues, whereupon the MEB(A) is also set for a data query by LPS 3B. Thus, the MEB(A) DESTINATION is set to LPS 3B and the EVENT to data in. The MEB(A) placed on the DISPATCH Q with MEB(B) remaining in the I/O and LPS 3A returns control to the DISPATCHER. In step 21, the Dispatcher dequeues the MEB(A)A and calls the LPS 3B. In step 22, the LPS 3B recognizing this is another session, i.e., Session A, allocates a CB to this session using the procedure ALLOCATE CB. A CB for the LPS 3B is thus allocated to the Session A by identifying the CB with with the MEB(A) Session Key and the LPSID. The LPS 3B then updates the allocated CB and continues to a disk I/O procedure. At this point, the MEB(A) is enqueued to the I/O Q with its event changed to do disk io. LPS 3B returns control to the DISPATCHER. This completes the Dispatch cycle which returns control to the Scheduler. At step 23, the scheduler checks the READY Q, finding it empty drops through to the I/O Q and calls for an I/O for the MEB(A) in the Q. At step 24, the procedure then returns after internal processing, and the Scheduler waits for a completion interrupt for the I/O of either the MEB(A) and MEB(B). In step 25, the Scheduler waits for a completion interrupt by calling the procedure wait on io. In this case, the disk I/O for the query for terminal 4b associated with the session B and MEB(B) completes, causing a completion interrupt. The I/O Handler then places the MEB(B) on the READY Q with its destination set at its previous ORIGIN, i.e., LPS 3A and returns control to the Scheduler. The MEB(A) is still in the I/O, since no completion interupt for this MEB for disk I/O has occurred. In step 26, the Scheduler loops back to check the READY Q, dequeues MEB(B) from the READY Q, enqueues it on the DISPATCH Q and calls the Dispatcher. In step 27, the DISPATCHER dequeues the DISPATCH Q, passing the MEB(B) to the LPS 3B, its DESTINATION. At this point, the MEB(A) remains in the I/O. At step 28, the LPS 3B recognizes from the EVENT disk io done of MEB(B) that the I/O for MEB(B) has been completed. It then calls its CB for the Session B, using the MEB(B) SESSION KEY and LPSID. After updating, the LPS 3B procedure continues, whereupon it is assumed that the data from the completed I/O on Session B has to be forwarded to LPS 3A. The LPS 3B thus changes the DESTINATION for the MEB(B) to LPS 3A, the ORIGIN for the MEB(B) to LPS 3B, and its EVENT to data out. The MEB(B) is then placed on the DISPATCH Q, while the MEB(A) still remains in the I/O. Control is returned to the Dispatcher. In step 29, the DISPATCHER dequeues the DISPATCH Q, passing the MEB(B) to the LPS 3A, its DESTINATION. MEB(A) remains in the I/O. At step 30, the LPS 3A recognizes from the EVENT data out of MEB(B) that the data carried on this MEB must be formatted for terminal I/O to terminal 4B associated with session B and MEB(B). After updating, the LPS 3A procedure continues, whereupon it prepares the MEB(B) for terminal I/O. The LPS 3A thus changes the DESTINATION to an insignificant value, the ORIGIN for the MEB(B) to LPS 3B, and its EVENT to do terminal io. The MEB(B) is then placed on the DISPATCH Q, while the MEB(A) still remains in the I/O. Control is returned to the Dispatcher. The Dispatcher, finding no MEBs on the DISPATCH Q, returns control to the Scheduler. In step 31, the Scheduler, finding no MEB on its READY Q, then falls through to the loop on the I/O Q. The Scheduler finds the MEB(B) in the I/O Q, dequeues the MEB(B) from the I/O Q, and invokes the I/O Handler by passing the MEB(B) as a parameter to the procedure do io. At this point, internal processing is carried out, and the I/O Handler returns control to the Scheduler. The Scheduler, finding no MEBs on the I/O Q, waits for an interrupt completion by calling wait on interrupt. Both MEB(A) and MEB(B) are in I/O. MEB(A) is still held by the I/O Handler for disk I/O, and MEB(B) is held by the I/O Handler for terminal I/O. In foregoing the illustrative example, it is apparent that the program 3 and control 3' allocate the MEB's on a session basis, two sessions being illustrated in the example. It is also apparent that the program 3 and control 3' cause the LPSs to allocate and have access to one CB per session and that access to the respective CB is through the SESSION KEY and the LPSID. These attributes of the system 1, as above-discussed, promote information hiding and enhanced performance. It should be noted that in the system 1, the CBs of the LPSs are not intended to be used to transfer information from one LPS to another, but rather to establish an environment for an LPS within a session. The CBs can be thought of as answering for their respective LPSs the questions "Where Was I When I issued the I/O or other request". In all cases, it is understood that the above-identified arrangements are merely illustrative of the many possible specific embodiments which represent applications of the present invention. Numerous and varied other arrangements can readily be devised in accordance with the principles of the present invention without departing from the spirit and scope of the invention. ##SPC1##
Apparatus including a program formed from Layered Procedure Sets and providing control for the program such that the message event blocks established for a session of the program are uniquely identifiable to the session and such that a single control block is established for a Layered Procedure Set during a session, the control block being uniquely identifiable to the Layered Procedure Set based on the particular session and the identification of the Layered Procedure set.
Briefly describe the main idea outlined in the provided context.
[ "This is a continuation application under 37 CFR 1.62 of prior application Ser.", "No. 07/452,065, filed Dec. 15, 1989, now abandoned.", "BACKGROUND OF THE INVENTION This invention relates to a method and apparatus for use with software programs and, in particular, to a method and apparatus for controlling operation and control block management of these programs.", "In computer operating systems in use today, the programs of the systems are often segmented into layers each of which contains a group of self-contained functions or procedures.", "Each such layer shall be referred to herein as a Layered Procedure Set or LPS.", "A basic model governing the communication of messages between and the invoking of LPSs in computer programs is the so-called queued "Scheduler-Dispatcher"", "model.", "This model is widely used in the data processing industry, especially in data communications.", "A particular data communications version of a Scheduler-Dispatcher model is described in Appendix C of IBM's SNA Format &", "Protocol Reference: Architectual Logic.", "In the queued Scheduler-Dispatcher functionality, message event blocks (MEBs) are used in conjunction with the Scheduler, Dispatcher and LPSs.", "MEBs provide an internal storage medium consistent enough in form to be able to pass messages identified as events and their associated control information from place to place within a program, and especially through the Scheduler and Dispatcher and between LPSs.", "In one version of the Scheduler-Dispatcher model, the Scheduler functions as a loop within a procedure.", "The Scheduler loop first waits on interrupts within the system and when an input/output ("I/O") procedure completes, identifies an associated MEB on its ready queue ("READY Q"), dequeues the MEB and enqueues it to the queue of the Dispatcher ("DISPATCH Q") and calls the Dispatcher.", "The Scheduler also acts on receiving control back from the Dispatcher to check its Ready Q and, if the READY Q contains an MEB, the Scheduler dequeues the MEB from the READY Q and enqueues it to the DISPATCH Q and calls the Dispatcher.", "If the READY Q is empty, however, the Scheduler checks the queue of the I/O ("I/O Q").", "If there is an MEB on the I/O Q, the Scheduler dequeues the MEB and passes it as a parameter for execution of the I/O procedure.", "When the Dispatcher is called by the Scheduler, the Dispatcher dequeues an MEB from its DISPATCH Q and calls the LPS associated with the destination contained in the MEB, passing the MEB as a parameter.", "When control is returned to the dispatcher from the LPS, the Dispatcher checks the DISPATCH Q to determine whether any MEBs are present.", "If the DISPATCH Q is empty, it returns control to the Scheduler.", "If the DISPATCH Q is not empty, the Dispatcher repeats its procedure until the DISPATCH Q is empty at which time It then returns control to the Scheduler for repeat of the Scheduler procedure.", "In the above operation of the Scheduler-Dispatcher model, the Scheduler, if there are no MEBs in the READY Q, checks the I/O Q to determine whether there are any MEBs present in this queue.", "If so, the Scheduler dequeues the MEB from the I/O Q to initiate execution of an I/O procedure.", "This is accomplished by an I/O handler ("I/O Handler") which begins execution upon a call from the Scheduler.", "This call is accompanied by passing of the MEB.", "Once the I/O handler has initiated the I/O operation, it returns control immediately to the Scheduler.", "To complete an I/O, the Scheduler invokes the I/O Handler by a call to the procedure wait on interrupt.", "The I/O Handler then checks for completion interrupts for the I/O operation (e.g., hitting of a key by a user).", "If a completion interrupt has occurred, the I/O Handler locates the MEB associated with that I/O, updates the MEB and enqueues it to the READY Q. If a completion interrupt has not occurred, the I/O Handler suspends processing and the process is idle until a completion interrupt actually OCCURS.", "The call by the Scheduler to the wait on interrupt procedure is completed when the I/O Handler returns control to the Scheduler.", "At this point, the Scheduler falls through, i.e., returns to, its READY Q loop procedure.", "In particular, the Scheduler initiates the LPS portion of its processing cycle by dequeuing the completed and updated MEB from the I/O operation in its READY Q, enqueuing the EMB to the Dispatch Q and then calling the Dispatcher.", "The LPS structure and the Scheduler-Dispatcher model with I/O Handler and MEBs is of considerable use in controlling execution and operation and control block management and storage in programs.", "It is particularly advantageous where the level of complexity of a program is such as to require the utilization of multiple LPSs for the purpose of modularity.", "It is also advantageous where multiple sessions are to be executed concurrently within the same program.", "As used herein, a session within a program may be thought of as one or more multi-threaded tasks intended to be completed as a unit.", "This unit, however, will not be executed continuously from start to finish and the execution of units of several sessions may be occurring concurrently.", "As an example, the tasks associated with the operation of a single terminal may be considered as a session, while the tasks associated with the operation of multiple terminals may be considered as multiple sessions.", "A typical example of a program requiring the LPS and Scheduler-Dispatcher structure might be a data communications program (e.g., SNA or OSI) where there are formally architectured functional divisions of labor and where there are many devices (terminals, remote computer systems, disk resources) which are being serviced simultaneously.", "While the LPS structure is highly advantageous, the manner of storage and management of the control blocks, both MEBs and layer control blocks ("CBs") which store control and other information associated with the LPSs, permits programming which can have undesired results.", "A typical data structure for such storage and management of MEBs and CBs is described and shown on page 8 of Appendix A of the aforementioned IBM reference.", "As shown by the illustrated Node Control Block (equivalent to an MEB), all the CBs are attached directly to the Node Control Block, are rigidly set forth or typed, and all CBs of all the layers (the equivalent of LPSs) are freely available to any other layer.", "With this type of storage and management for the CBs, it becomes possible for one LPS to access and alter the content of the CB of another LPS.", "Such alteration, if it occurs, can have a detrimental effect on program operation, since the second LPS may need its unaltered CB in continuing a procedure.", "It also inhibits so-called "information hiding", which has been found to be beneficial to program operation and management.", "It is, therefore, an object of the present invention to provide a method and apparatus for program control and operation which tends to mitigate the aforesaid disadvantages.", "It is a further object of the present invention to provide a method and apparatus for program control in an LPS architectured system which is structured to establish privacy of each CB with respect to its LPS.", "It is a further object of the present invention to provide a method and apparatus for program control in an LPS architectured system wherein access of an LPS to a CB of another LPS is inhibited.", "It is yet a further object of the present invention to provide a method and apparatus for program control in an LPS architectured system wherein information hiding is promoted.", "SUMMARY OF THE INVENTION In accordance with the principles of the present invention, the above and other objectives are realized by configuring the program and program control of an LPS based system such that the MEBs established in the program for a particular session are associated only with that particular session.", "The program and control are further configured such that each LPS is allocated only a single CB for a particular session, which CB is only accessible by that LPS and not other LPSs during the session.", "In the embodiment of the invention to be disclosed hereinafter, an MEB established for a session carries an identifier (referred to as a SESSION KEY) which uniquely allocates the MEB to the session for which it was established.", "Similarly the CB of an LPS for a particular session, is associated with the SESSION KEY for that session, as well as with the identifier of the LPS (referred to as "LPSID") for which the CB was established.", "In this way, each established MEB is allocated to a particular session and each established CB is allocated to a particular LPS in a particular session.", "Furthermore, each LPS is constrained to invoke only a SESSION KEY and its LPSID when developing a pointer for a CB.", "As a result, an LPS is compelled to retrieve only its own CB and access to the CBs of other LPSs is inhibited.", "In further aspects of the invention, access to a particular LPS is confined to a single entry point (referred to as the Entry Router) and exit from the LPS to a particular exit point (referred to as the Exit Router) so as to prevent calling of procedures within an LPS directly from outside the LPS.", "Also the programming and CB storage control and management is such that the storage scheme for the CB of an LPS is unknown to the LPS.", "In addition, the programming inhibits the LPS from accessing sessions other than that of a current MEB.", "These requirements along with permitting an LPS to access only its own allocated CB in a session, facilitate the information hiding aspects of the system.", "BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and aspects of the present invention will become more apparent upon reading the following detailed description conjunction with the accompanying drawings, in which FIG. 1 illustrates a computing apparatus and associated terminals in accordance with the principles of the present invention;", "FIG. 2 shows the details of a portion of the program execution and control system of the apparatus of FIG. 1;", "FIG. 3 shows the structure of an MEB used in the program execution and control system of FIG. 2;", "FIG. 4 shows in greater detail an LPS used in the system of FIG. 1;", "FIGS. 5-7 show diagrammatically an example of the sequence of operation of the program of the apparatus of FIG. 1;", "and FIGS. 7-21 the program flow corresponding to the operating sequence of FIGS. 5-6.", "DETAILED DESCRIPTION FIG. 1 shows a computing apparatus or system 1 including a program execution and control operating system 2 for executing a program 3 comprised of a plurality of LPSs 3A, 3B .", "3N and a program control means 3'", "which is described in greater detail hereinabelow.", "The apparatus 1 is addressed by a plurality of terminals 4A, 4B and communicates with a plurality of storage units or disks 5A, 5B.", "The computing apparatus 1 can be any type of computing apparatus with a processing environment similar to that of UNIX and a programming environment like that of C. Such computing apparatus can support the program 3 with LPSs 3A to 3N.", "For example, the computing apparatus might be an IBM PC with an MS-DOS operating system or a DEC VAX with a VMS operating system, or the environment on which the LPS program originated, Tandem NonStop with Guardian.", "The program 3 is a single program instantiated as a single running process.", "The terms process and program are intended to convey the equivalent of a UNIX program and process.", "In the present illustrative case, the program 3 is complex enough to be divided into functionally discrete groupings of functions or procedures which are multi-threaded in nature (i.e., several actions can be taken place concurrently).", "As above-indicated, each LPS 3A to 3N is an entirely self contained group of functions or procedures.", "Furthermore, in accordance with the invention, entry into and exit from each LPS 3A to 3N is through a single procedure.", "These attributes for each of the LPSs 3A to 3N are illustrated for the LPS 3A in FIG. 4. As shown, the LPS 3A contains procedures Proc 1 to Proc 3 and entry into the LPS 3A is through a single procedure, called only by the Dispatcher (described below), identified as Entrance Router;", "and exit is also through a single procedure, and identified as the Exit Router.", "By exit is meant the issuance of MEBs to other LPSs or the I/O Handler (described below).", "More particularly, a procedure in LPS 3A is indirectly invoked as a function of the input handling performed by the Entrance Router for that LPS.", "A procedure within an LPS 3A, on the other hand, cannot generate output, except by invoking the Exit Router for that LPS.", "FIG. 2 shows the program control means 3'", "which supports control of inputs and outputs in and to the program 3 and, in particular, in, to and between the LPSs 3A to 3N.", "This program control means 3'", "of the program 3 is in the form of the Scheduler-Dispatcher model and I/O Handler discussed above.", "Thus, as shown, in FIG. 2, the execution section 2A comprises a Scheduler 21, Dispatcher 22, I/O Handler 23, I/O Q 24, READY Q 25 and DISPATCH Q. These elements function as previously described above for the Scheduler-Dispatcher model in interacting with the LPSs 3A to 3N within the program 3.", "The program control means 3'", "also includes a Control Manager 27 which acts also as a secondary scheduler for the output MEBS from the LPSs 3A to 3N routing them to the I/O Q and the DISPATCH Q as determined by the outputs.", "FIG. 3 shows the structure of an MEB utilized in the program 3 and program control means 3'", "for conveying messages.", "As shown, the MEB includes usual fields marked ELEMENT, ORIGIN, DESTINATION, EVENT, DATA COUNT, DATA, and USER DATA.", "Of these, the fields DESTINATION and ORIGIN provide information as to the next element to be receiving the MEB (DESTINATION) and the element which last received the MEB and its associated message (ORIGIN).", "In the case of messages to and from an LPS, these fields would contain the identifier LPSID of the particular LPS.", "ELEMENT refers to any LPS or the I/O Handler.", "The fields DATA and DATA COUNT are pointers to a message buffer and the size of the buffer respectively.", "The field EVENT designates the event to be invoked by the MEB.", "In accordance with the principles of the present invention, the MEB is adapted to include a further field which specifically identifies the MEB with a particular session of the program 3.", "In the case shown, this field is identified as Session Key.", "The Session Key ties the MEB to a particular session.", "Recognizing the need for passing information between LPSs (normally accomplished by direct access of CBs by LPSs), a USER DATA pointer field is provided for the MEB and is constrained to contain only data specifically required for inter LPS communication.", "More general data concerning each LPS is thus not available from this field, thereby promoting hiding of the LPS data.", "An MEB is generated by the program 3 upon the establishment of each new session.", "The MEB is created by a procedure or function within the program 3 by calling the procedure CREATE MEB.", "The called procedure responds by creating an MEB having a SESSION KEY or pointer which identifies the session uniquely and the place in memory allocated to the session.", "The allocated memory location can then be accessed for later use by LPSs invoking specific procedures detailed hereinbelow passing the Session Key as a parameter.", "The creation of an MEB may likely be performed upon initialization of the program 3, as by one of the terminals 4A, 4B being brought into operation.", "Each initialization of a different terminal amounts to a new session and each new session establishes another MEB with a Session Key allocated to that session.", "Once an MEB with a Session Key has been established for a session, the LPSs 3A to 3N can duplicate the created MEB by calling the procedure CLONE MEB.", "This procedure creates a new MEB based on the original MEB passed with the call and the new MEB has the same SESSION KEY and identifier as the original MEB.", "Also, each LPS can destroy an existing MEB allocated to a session by calling the procedure PUT MEB.", "If the MEB is the only one allocated to the session, the session as well as the MEB will be terminated.", "As above-indicated, each of the LPSs is identified with an identifier LPSID which identifies it uniquely among the LPSs within a single program.", "In further accordance with the invention, the program 3 and control means 3'", "are such that each LPS is further allocated only a single CB and corresponding memory storage area for each program session.", "The CB is established by the LPS calling the procedure ALLOCATE CB which then allocates a CB using the LPSID of the LPS and the MEB SESSION KEY as unique identifiers.", "In allocating a CB, the length of the CB is determined by the LPS in the ALLOCATE CB instruction to insure complete flexibility in the CB format.", "The program 3 and control means 3'", "are also such that storage of an allocated CB of an LPS is unknown to the LPS until retrieval of a CB which can only be achieved by the LPS calling FIND CB with the LPSID and SESSION KEY.", "Likewise, a CB of an LPS can be removed from a session by calling DEALLOCATE CB again using only the combination of LPSID and SESSION KEY.", "Illustrative Examples, of procedures for CREATE MEB, CLONE MB, PUT MEB, ALLOCATE CB, FIND CB and DEALLOCATE CB are set forth in the attached Appendix I, pages A14-20, which is made a part hereof.", "By requiring that a LPS only have access to a CB in a session by calling its LPSID and the SESSION KEY, an LPS is given access only to its own CB.", "Thus, access to and altering of another LPS's CB is prevented.", "Furthermore, the programming 3 and control means 3'", "are such that each LPS can only access the session of the current MEB.", "These atributes of the LPSs foster information hiding in the program 3.", "FIGS. 5-7 show diagrammatically an example of the sequence of operation of the system 1 during initialization of the terminals 4A, 4B and during subsequent entry of inputs at the terminals, respectively.", "FIGS. 7-21 illustrate the program flow corresponding to the operating sequences of FIGS. 5-7.", "An example of a short program for performing the sequence of operation in FIGS. 5-7 is set forth in the aforementioned Appendix I, at pages A1-A13, with the steps in FIGS. 5-7 being indicated on the corresponding program parts.", "In the operating sequence of the above figures, it is assumed that both terminals 4A and 4B turn on requiring two sessions designated A and B which will operate concurrently.", "It is further assumed that during these sessions both terminals will specify events requiring procedures of LPSs 3A and 3B.", "Prior to initialization, the READY Q, DISPATCH Q and I/O Q are empty and there are no MEBs present.", "Upon initialization of the terminals 4A and 4B, program 3 invokes sequence steps 1 and 2 in which the program creates a first MEB(A) associated with the session A of the terminal 4A and a second MEB(B) associated with the session B of the terminal 4B.", "These MEBs are placed on the READY Q for processing by the Scheduler at step 3.", "The Scheduler dequeues the MEB(A) from the READY Q to the DISPATCH Q and calls the Dispatcher.", "At step 4, the Dispatcher dequeues the MEB(A) to the LPS 3A identified by the LPSID in the DESTINATION block of the MEB.", "In step 5, the LPS 3A processes the MEB(A) in accordance with the EVENT block which indicates initialization.", "LPS 3A thereupon allocates a CB to itself and identifies the CB with the MEB(A) SESSION KEY and with the LPSID of LPS 3A.", "The MEB(A) through the program manager is then placed on the I/O Q. That completes the Dispatch cycle for the MEB(A) and control returns to the Scheduler.", "In steps 6, 7, 8 and the steps 3, 4 and 5 are repeated for the MEB (B), resulting in a second CB for the LPS 3A being established for the session B, which CB is uniquely identified by the MEB<B) session Key and the LPSID of LPS 3A.", "Step 8 completes the second Dispatch cycle and both MEB(A) and MEB(B) are on the I/O Q. In step 9, the Scheduler finds no MEBs in its READY Q and thus falls through to the I/O Q which now contains MEB(A) and MEB(B).", "The Scheduler dequeues MEB(A) and calls for an I/O.", "The Scheduler then in step 10 again continues its loop on the I/0 Q, dequeues MEB(B) and calls for an I/O.", "In step 11, the Scheduler then waits for a completion interrupt for an I/O procedure.", "In the present case, it is assumed that the I/O for terminal 4B associated with the session B and MEB(B) completes first (e.g. user on terminal 4B hits enter key) causing a completion interrupt.", "The I/O Handler then places the MEB(B) on the READY Q with its DESTINATION set at its previous ORIGIN, i.e., LPS 3A and returns control to Scheduler.", "The MEB(A) is still in the I/O, since no completion interrupt for this MEB has occurred.", "In step 12 the Scheduler loops back to check the READY Q dequeues MEB(B) from the READY Q, enqueues it on the DISPATCH Q and calls the Dispatcher.", "In step 13, the DISPATCHER dequeues the DISPATCH Q, passing the MEB(B) to the LPS 3A, its DESTINATION.", "At this point, the MEB(A) still remains in the I/O.", "At step 14, the LPS 3A, recognizes from the EVENT of MEB(B) that the I/O for MEB(B) has been completed.", "It then calls its CB for the Session B, using the MEB(B) SESSION KEY and LPSID.", "After updating, the LPS 3A procedure continues, whereupon it is assumed that a query regarding the session B has been made to LPS 3A by the user.", "The LPS 3A thus changes the DESTINATION for the MEB(B) to LPS 3B and its event to data in to satisfy the query.", "The MEB(B) is then placed on the DISPATCH Q, while the MEB(A) still remains in the I/O.", "In step 15, the Dispatcher dequeues the DISPATCH Q passing the MEB(B) to the LPS 3B by calling this LPS.", "At step 16, the LPS 3B, recognizing this as a new session, establishes a CB for the new session B by calling the procedure ALLOCATE CB.", "The CB is then allocated using the MEB(B) SESSION KEY and the LPSID as identifiers.", "The LPS 3B then updates and its procedure continues, whereupon it calls for a disk I/O.", "The MEB(B) is then placed on the I/O Q with its EVENT changed to do disk The MEB(A) still remains in the I/O.", "Since there are no MEBs on the DISPATCH Q, this ends the dispatcher cycle.", "Return of control is thus made to the Scheduler in step 17.", "The Scheduler, finding nothing in its READY Q, then falls through to the I/O Q. The Scheduler finds MEB(B) in the I/O Q and dequeues MEB(B) calling for an I/O at step 17.", "At this point, internal processing is carried out, the I/O Handler returns control to the Scheduler, and the Scheduler waits for a completion interrupt for an I/O by calling the procedure wait on interrupt, since both MEB(A) and MEB(B) are in I/O.", "In step 18, the I/O for MEB(A) completes.", "The MEB(A) is placed by the I/O Handler on the READY Q with its DESTINATION LPS 3A and its EVENT changed to io done.", "Control is returned to the Scheduler.", "The Scheduler then calls the Dispatcher after the MEB(A) is dequeued from the READY Q and enqueued to the DISPATCH Q, while the MEB(B) remains in the I/O.", "In step 19, the Dispatcher dequeues the DISPATCH Q passing the MEB(A) to LPS 3A, the MEB(B) still remaining in the I/O.", "In step 20,the LPS 3A recognizes that the I/O has been completed and calls its CB for the session A with the MEB(A) SESSION KEY and LPSID.", "The Session A CB is updated and the procedure continues, whereupon the MEB(A) is also set for a data query by LPS 3B.", "Thus, the MEB(A) DESTINATION is set to LPS 3B and the EVENT to data in.", "The MEB(A) placed on the DISPATCH Q with MEB(B) remaining in the I/O and LPS 3A returns control to the DISPATCHER.", "In step 21, the Dispatcher dequeues the MEB(A)A and calls the LPS 3B.", "In step 22, the LPS 3B recognizing this is another session, i.e., Session A, allocates a CB to this session using the procedure ALLOCATE CB.", "A CB for the LPS 3B is thus allocated to the Session A by identifying the CB with with the MEB(A) Session Key and the LPSID.", "The LPS 3B then updates the allocated CB and continues to a disk I/O procedure.", "At this point, the MEB(A) is enqueued to the I/O Q with its event changed to do disk io.", "LPS 3B returns control to the DISPATCHER.", "This completes the Dispatch cycle which returns control to the Scheduler.", "At step 23, the scheduler checks the READY Q, finding it empty drops through to the I/O Q and calls for an I/O for the MEB(A) in the Q. At step 24, the procedure then returns after internal processing, and the Scheduler waits for a completion interrupt for the I/O of either the MEB(A) and MEB(B).", "In step 25, the Scheduler waits for a completion interrupt by calling the procedure wait on io.", "In this case, the disk I/O for the query for terminal 4b associated with the session B and MEB(B) completes, causing a completion interrupt.", "The I/O Handler then places the MEB(B) on the READY Q with its destination set at its previous ORIGIN, i.e., LPS 3A and returns control to the Scheduler.", "The MEB(A) is still in the I/O, since no completion interupt for this MEB for disk I/O has occurred.", "In step 26, the Scheduler loops back to check the READY Q, dequeues MEB(B) from the READY Q, enqueues it on the DISPATCH Q and calls the Dispatcher.", "In step 27, the DISPATCHER dequeues the DISPATCH Q, passing the MEB(B) to the LPS 3B, its DESTINATION.", "At this point, the MEB(A) remains in the I/O.", "At step 28, the LPS 3B recognizes from the EVENT disk io done of MEB(B) that the I/O for MEB(B) has been completed.", "It then calls its CB for the Session B, using the MEB(B) SESSION KEY and LPSID.", "After updating, the LPS 3B procedure continues, whereupon it is assumed that the data from the completed I/O on Session B has to be forwarded to LPS 3A.", "The LPS 3B thus changes the DESTINATION for the MEB(B) to LPS 3A, the ORIGIN for the MEB(B) to LPS 3B, and its EVENT to data out.", "The MEB(B) is then placed on the DISPATCH Q, while the MEB(A) still remains in the I/O.", "Control is returned to the Dispatcher.", "In step 29, the DISPATCHER dequeues the DISPATCH Q, passing the MEB(B) to the LPS 3A, its DESTINATION.", "MEB(A) remains in the I/O.", "At step 30, the LPS 3A recognizes from the EVENT data out of MEB(B) that the data carried on this MEB must be formatted for terminal I/O to terminal 4B associated with session B and MEB(B).", "After updating, the LPS 3A procedure continues, whereupon it prepares the MEB(B) for terminal I/O.", "The LPS 3A thus changes the DESTINATION to an insignificant value, the ORIGIN for the MEB(B) to LPS 3B, and its EVENT to do terminal io.", "The MEB(B) is then placed on the DISPATCH Q, while the MEB(A) still remains in the I/O.", "Control is returned to the Dispatcher.", "The Dispatcher, finding no MEBs on the DISPATCH Q, returns control to the Scheduler.", "In step 31, the Scheduler, finding no MEB on its READY Q, then falls through to the loop on the I/O Q. The Scheduler finds the MEB(B) in the I/O Q, dequeues the MEB(B) from the I/O Q, and invokes the I/O Handler by passing the MEB(B) as a parameter to the procedure do io.", "At this point, internal processing is carried out, and the I/O Handler returns control to the Scheduler.", "The Scheduler, finding no MEBs on the I/O Q, waits for an interrupt completion by calling wait on interrupt.", "Both MEB(A) and MEB(B) are in I/O.", "MEB(A) is still held by the I/O Handler for disk I/O, and MEB(B) is held by the I/O Handler for terminal I/O.", "In foregoing the illustrative example, it is apparent that the program 3 and control 3'", "allocate the MEB's on a session basis, two sessions being illustrated in the example.", "It is also apparent that the program 3 and control 3'", "cause the LPSs to allocate and have access to one CB per session and that access to the respective CB is through the SESSION KEY and the LPSID.", "These attributes of the system 1, as above-discussed, promote information hiding and enhanced performance.", "It should be noted that in the system 1, the CBs of the LPSs are not intended to be used to transfer information from one LPS to another, but rather to establish an environment for an LPS within a session.", "The CBs can be thought of as answering for their respective LPSs the questions "Where Was I When I issued the I/O or other request".", "In all cases, it is understood that the above-identified arrangements are merely illustrative of the many possible specific embodiments which represent applications of the present invention.", "Numerous and varied other arrangements can readily be devised in accordance with the principles of the present invention without departing from the spirit and scope of the invention.", "##SPC1##" ]
BACKGROUND 1. Field of Invention Packaging and containers are among the wide variety of applications where RFID (radio frequencies identification) transponders or tags are currently being used by the many hundreds of millions. The highest volumes of tags generally comprise a passive antenna and unique signature identifier chip integrated within a product or packaging which in operation, can be detected at points within the product distribution cycle. When data associated with the product is to be accessed, the product tag is caused to resonate a signature that is distinguishable from others when compared to a database of resonation signatures. The matching signature within the database then is used to call up details from the database about the product associated with the sensed tag signature. Active RFID tags are also known which operate similarly to passive RFID tags except that they are integrated with a power source to enhance transmission of information. 2. Description of Prior Invention The vast majority of prior art relates to passive RFID tag systems where an individual item has an individual tag with and individual unique signature associated with it. The individual tag will stay with the item through a portion of the distribution cycle and generally not be altered during the distribution cycle except possibly when the product moves out of the distribution system (is purchased by a customer) at which time the RFID tag may be deactivated in some instances. Some prior art describes RFID tags that can be altered by a worker in the product distribution cycle to customize information about the product. For example, U.S. Pat. No. 4,889,961 (Carlson) describes a process whereby a worker draws a line with a conductive material which completes a circuit as a mechanism to customize and alter the information communicated by an RFID tag. Similarly, U.S. Pat. No. 6,805,291 (Chhatpar et al) describes a process whereby a worker can utilize a writing instrument such as a pencil, printer, and/or eraser to connect and disconnect circuits associated with an RFID tag to modify the RFID signature of the tag. The process of modifying an RFID circuit using a writing instrument such as a pencil, eraser, and/or printer being further described in U.S. Pat. No. 6,840,444 (Pierce et al), U.S. Pat. No. 6,869,020 (Foth et al), and U.S. Pat. No. 6,869,021 (Foth et al). The prior art described in this paragraph generally representing examples of configurable or reconfigurable RFID tags using connectable and disconnectable contacts and associated circuits whereby the individual signatures of individual tags are configured or reconfigured to represent information. BRIEF SUMMARY The invention described herein represents a significant advancement in use configurable and reconfigurable RFID readable data by the introduction of RFID readable free form sheets of a plurality of RFID signatures that are alterable by a user. Freeform sheets are a novel basis for enabling hand written or printed text to be read using RFID techniques according to a process such as the following preferred embodiment. A plurality of individual RFID transponder signatures is arrayed on a substrate sheet. Each transponder in the plurality has a unique signature and a known physical position on the substrate which is stored as a map in a memory. Each unique signature is user alterable with regard to changing detectibility, frequency, intensity, and/or modulation. Using a writing instrument such as either a pen, an eraser, or a printer, the user interacts with the sheet to alter some of the unique tags for example by writing a word on the sheet. The sheet is then read using RFID techniques such that each individual tag that produces an altered or unaltered readable signal is sensed, registered, and plotted against the map of the sheet in memory using the predetermined positional relationships of the individual signatures in the array. This sensed map is then interpolated using automatic charter recognition software to convert the map into alpha numeric data which is stored in a database or used in determining the routing or processing of the sheet and/or the article or product associated with the sheet. Thus user alteration of individual unique signatures on the freeform sheet forms the basis of communicating data in the form of a map of altered and unaltered individual unique tags that are interpolated using character recognition software into meaningful hand written words, printed words, alphanumeric characters, diagrams, or indicia that can be stored in a database, and or used for processing the sheet and/or an item associated with the sheet. Thus the present invention offers a significant advancement in the ability to communicate an unlimited range of information on a single freeform RFID readable sheet. Objects and Advantages Accordingly, several objects and advantages of the present invention are apparent. It is an object of the present invention to provide a means to reliably and inexpensively communicate a very wide range information using an RFID technique. It is an object of the present invention to provide an RFID freeform field where data can be written in by hand and automatically be stored in a database as alphanumeric data associated with an object, a product, or a person. It is an object of the present invention to provide an RFID freeform field where data can be printed in and automatically stored in a database as alphanumeric data associated with an object, a product, or a person. It is an object of the present invention to provide an RFID freeform field where data can be erased by hand and automatically be altered in a database as alphanumeric data associated with an object, a product, or a person. It is an advantage that a user can communicate information without the need of special equipment. It is an advantage of the present invention that a user can write words on a medium that are RFID readable. It is an advantage of the present invention that hand written words can be converted to data autonomously and without the need for special equipment. It is an advantage of the present invention that it can utilize nearly any transponder chip, circuit, and antenna that is known in the RFID industry. For example where multiple chips are utilized with individual antennae, and where multiple chips are utilized with a common antennae, the so called “mu-chip” from Hitachi, Ltd. can be utilized with the present invention. It is an advantage of the present invention that it can utilize nearly any reader that is known in the RFID industry. It is an advantage of the present invention that it can utilize many reading approaches such as ALOHA, tree walking or binary tree, FDMA, and CDMA. It is an advantage of the present invention that each RFID signature in the plurality of signatures arrayed on a substrate sheet can be truly unique. Alternately, the substrate sheet may have a single unique identifier signature with all of the other signatures being standard for the class of substrate sheets. Further objects and advantages will become apparent from the enclosed figures and specifications. DRAWING FIGURES FIG. 1 a illustrates a sheet of a plurality of exposed arrayed individual unique signature RFID transponders. FIG. 1 b illustrates the sheet of FIG. 1 a with a word printed thereon. FIG. 2 a illustrates a letter hand printed on the sheet of FIG. 1 a. FIG. 2 b illustrates an RIFD sensed map of the letter of FIG. 2 a and the RFID sensing process. FIG. 3 a illustrates a sheet of a plurality of covered arrayed individual unique signature RFID transponders. FIG. 3 b illustrates the sheet of FIG. 3 a with a word printed thereon. FIG. 4 a illustrates a letter hand printed on the sheet of FIG. 3 a. FIG. 4 b illustrates an RIFD sensed map of the letter of FIG. 4 a and the RFID sensing process. FIG. 5 a illustrate a sheet of a plurality of arrayed RFID tags each having a unique signature with printed indicia and a selection made. FIG. 5 b illustrates a side view of a small section of FIG. 1 a. FIG. 5 c illustrates a side view of a small section of FIG. 1 b. FIG. 5 d illustrates a side view of a small section of FIG. 3 a. FIG. 5 e illustrates a side view of a small section of FIG. 3 b. FIG. 5 f illustrates a side view of a small section of FIG. 3 a in an alternate embodiment. FIG. 5 g illustrates a side view of a small section of FIG. 1 b in an alternate embodiment. FIG. 6 a illustrates a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a detectible format. FIG. 6 b illustrates the elements of FIG. 6 a with indicia printed thereon. FIG. 6 c illustrates the signature map of the elements of FIG. 6 b when being sensed using RFID and plotted against a map in memory. FIG. 7 a illustrates a side view a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a non-detectible format. FIG. 7 b illustrates the elements of FIG. 7 a with indicia printed thereon. FIG. 7 c illustrates the signature map of the elements of FIG. 7 b when being sensed using RFID and plotted against a map in memory. FIG. 8 a illustrates a side view of a RFID free form label with indicia printed thereon and stuck to the side of a box. FIG. 8 b illustrates a top view of a RFID free form label with indicia printed thereon and stuck on an envelope. FIG. 9 illustrates a process flow chart of sensing altered RFID signatures and for converting sensed signatures of written indicia into data. FIG. 10 illustrates a simple circuit that can serve as a writable and erasable physical indicia based memory and sensor. FIG. 11 illustrates a process for communicating indicia stored in written form according to FIG. 10 and for sensing indicia and translating the indicia to data to be utilized in additional processes. FIG. 12 a illustrates an RFID transponder or tag formed by a simple circuit integrated with the indicia memory circuit according to FIG. 10 . FIG. 12 b illustrates an RFID transponder or tag formed by a circuit architecture common to Texas Instruments RFID devices integrated with the indicia memory circuit according to FIG. 10 . DETAILED DESCRIPTION OF THE INVENTION First Embodiment Multiple RFID Devices Comprise One Tag or Transponder FIG. 1 a illustrates a sheet of exposed arrayed individual RFID devices each having a unique signature. A first substrate 127 comprises a sheet such as paper upon which is affixed or otherwise deposited an array of RFID antennae such as a first antenna 121 which is connected to a first chip (not visible) and in operation produces a first RFID signature, a second antenna 123 which is connected to a second chip (not visible) and in operation produces a second RFID signature, and a third antenna 125 which is connected to a third chip (not visible) and in operation produces a third RFID signature. All of the dozens of individual RFID antenna of FIG. 1 a in combination with respective chips are capable of producing a respective individual RFID signature that differentiates it from others on the sheet. As described in FIG. 2 b , the positions of each respective transmitting antenna is known and its location on the sheet substrate together with its signature is stored in a database which is used in reading and interpreting changes made on the sheet. The 121 , 123 , and 125 comprising a plurality of devices on a substrate including a first device capable of producing a first signature, a second device capable of producing a second signature, and a third device capable of producing a third signature. FIG. 1 a depicting a plurality of transponders in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip. FIG. 1 b illustrates the sheet of FIG. 1 a with a word printed thereon. In a printing process, an RF interfering or otherwise electrically conducting ink is printed upon the surface of the first substrate sheet 127 including a first letter “D” 129 . In a first alternative approach, the ink is deposited directly upon and has electrical communication with antennae and/or associated circuitry upon which it is printed so as to effectively short circuit or modify their respective RF signatures while not having electrical communication with antennae and/or associated circuitry upon which it is not printed and not altering their signatures. In a second alternative approach, the ink has an RF signal interfering or blocking effect on antennae and/or antennae circuitry upon which it is printed while not having an RF signal interfering or blocking effect on antennae and/or antennae circuitry upon which it is not printed. In ether case, the RFID signature of each antenna covered by ink in FIG. 1 b is altered from its original respective signature when it was not covered by ink as in 1 a . Thus a first altered antenna 121 a produces either no signature or an altered signature as compared to the first antenna 121 of FIG. 1 a and a second altered antenna 123 a produces either no signature or an altered signature as compared to the second antenna 123 of FIG. 1 a . Note that the third RFID signature produced by the third antenna 125 is not altered by the printing process since it is neither in electrical contact with the ink nor covered by RF interfering ink. The process described in FIG. 2 b will map the altered antennae compared to the unaltered antennae as a step to reading the words that have been printed upon the substrate sheet. It should be noted that the size of the antennae compared to the size of the sheet and the size of the print can be altered in scale such that a single letter may cover dozens of antennae to increase the resolution when read in the process of FIG. 2 b . Suitable inks and printing processes are know in the prior art some of which are reference in the above Prior Invention section. FIG. 1 b depicting a single transponder or tag which comprises a plurality of transponders or tags in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, and/or modulation. FIG. 2 a illustrates a letter hand printed on the sheet of FIG. 1 a . A writing instrument such as a pencil contains an electrically conductive or RF interfering composite including for example graphite which may also be erasable. Suitable hand writing instruments such as pencils, erasers, pens, and styluses are described in the prior art some of which is referenced in the above Prior Invention section. For antennae upon which the pencil writes, the RFID signatures are altered as described in FIG. 1 b . For antennae upon which the pencil does not write, the antennae RFID signatures are unaltered from those described in FIG. 1 a and in a database describing signatures and signature according to FIG. 2 b . Alternately, to alter the signature of select antennae, the writing instrument can be a stylus used to break the antennae or associated circuitry according to FIGS. 5 c and 5 g . Thus a first hand written letter “D” 129 b is written upon the substrate sheet 127 whereby the RF signatures of covered (or partially covered) antennae are altered such as first hand instrument altered antenna 121 b , and second hand instrument altered antenna 123 b . Those antennae with altered signatures no longer match the signatures of the original sheet of FIG. 1 a and as further described in the reading described in FIG. 2 b reading and interpolating processes. Signatures of antennae that were not written on such as the third antenna 125 are not altered and are still capable of producing their original RFID signatures. FIG. 2 a depicting a plurality of transponders or tags in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures have been altered by a user writing indicia whereby RFID detectibility, intensity, frequency, and/or modulation has been altered in the writing of the indicia. FIG. 2 b illustrates an RIFD sensed map of the letter “D” of FIG. 2 a and the RFID sensing and interpreting processes. After being written on with a writing instrument or with a printer, the signatures of altered antennae and/or associated circuitry will not match those original signatures in a database 141 . Each antenna that can be read according to its original signature has a known signature and a known positional relationship such as the individual respective double-digit numbers in FIG. 2 b . In operation, an RF transmitter 133 emits energy that causes the unaltered antennae on the substrate sheet 127 to emit their specific signatures which are received by an RFID receiver 135 , the signatures are compared to a map in the database to form an altered signature map which can be displayed 137 . The map comprising spots (or pixels) on the sheet where received antennae signatures match those in the database such as the double-digit numbers including third antenna 125 . The map also comprising spots (or pixels) where the signatures of antennae at specific frequencies have not been received such as the first altered antenna 121 b and the second altered antenna 123 b . Such altered antennae being mapped as the printed or written indicia that was placed upon the sheet substrate in FIGS. 1 b , and/or 2 a . In order to convert the altered sheet map to data, an interpolator 139 compares the map to a database of known alphanumeric characters or other indicia to discern what the map says. Once the alphanumeric characters are interpolated, they can be stored in the database or displayed as text 143 on a screen. A vast number of processes 145 such as shipping, or distribution instructions can be executed by comparing a keyword list in the database to words that are interpolated from the sheet and stored in the database. For example, if the words written contain a zip code, keyword processes can automatically route a package associated with the sheet to the appropriate zip code written thereon. Thus a very wide range of hand written or printed information can be converted to executable data using the RFID technique described herein. The transmitter, receiver, database, and keyword processes being well known in the prior art. The interpolator 139 being virtually identical to those employed for optical character recognition (OCR) processes except with the advantage that whereas optical scanning of the sheet requires that an optical scanner be in a certain close tolerance proximity to the sheet, the RFID scanning technique can be employed from a far greater distance and tolerance than can optical scanning. The character recognition process herein utilizing a directory of indicia, alphanumeric characters, words, symbols, patterns, or physical relationships that can be used to compare against the sensed map for the purpose of identifying recognizable characters or content. Thus steps of the present invention may include; depositing a plurality of antennae upon a substrate sheet wherein each respective antenna (and associated chip) is capable of producing a respective RFID signature, storing in a database (or memory) the data describing the respective RFID signatures and a map of physical positions on the sheet of each associated respective antenna, the writing of indicia on the sheet of antennae that alters the properties of RFID signatures of some antennae (and associated chips) on the sheet, using RFID to sense antennae on the sheet, comparing sensed signatures information to possible signatures information in the database to produce an altered antennae map of the sheet, displaying of the altered antennae map, storing of the altered antennae map in the database, a character recognition step where the altered antennae map is compared with a database of characters to convert the map into alphanumeric or other indicia data, displaying of the alphanumeric or other indicia data, storing of the alphanumeric or other indicia data in the database, comparing the data to a database of possible data for the purpose of controlling processing of the sheet and/or a physical object associated with the sheet; and/or whereby a writing on the sheet is used to control processing of the sheet. FIG. 2 b depicting a plurality of transponders or tags in array whereby some are RFID readable and having a signature corresponding to one stored in memory. FIG. 2 b further depicting a plurality of transponders or tags in array whereby RFID signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, and/or modulation. FIG. 2 b also depicting an RFID process whereby a plurality of RFID signatures are sensed by an RFID reader, the signatures that are sensed are compared to those in memory and are mapped to specific relative predefined positions in memory to establish which areas of the substrate sheet have been altered and which remain unaltered. A map of altered or unaltered signatures is then compared to indicia stored in memory such as is common with OCR (optical character recognition) software and processes. The sensed RFID signatures thereby being used to convert hand written or typed indicia to recognized data for storage in memory and use is processes. FIG. 3 a illustrates a sheet of covered arrayed individual unique RFID devices each having a unique signature. A blocked antennae array sheet 157 is identical to the substrate sheet 127 of FIG. 1 a except that all of the antennae are blocked from producing their respective RF signatures stored in the database as further described in FIGS. 5 d , 5 e , and 5 f . A first blocked antenna 151 , a second blocked RF antenna 155 , and a third blocked antenna 153 are covered by a material such as a thin aluminum foil deposition so that their unique signatures can not be detected by the RFID process. FIG. 3 a depicting a plurality of transponders in array each being shielded from being RFID readable and having a unique signature and comprising a respective antenna and a respective chip. FIG. 3 b illustrates the sheet of FIG. 3 a with a word printed thereon. Indicia can be printed on the altered covered sheet 157 a such as a printed “R” 159 . When the indicia is printed upon the 157 a , it destroys the blocking layer thereby exposing underlying antennae including a first exposed antenna 151 a , and a second exposed antenna 155 a . The exposure can be facilitated by a chemical process that destroys the ability of the blocking deposition from effectively blocking the RFID antennae signatures. Alternately, a mechanical process may be utilized such as is described in FIG. 4 a . In either case, the blocking property of material covering antennae which are not printed on, is not changed by the printing process including third blocked antenna 153 which can not produce the RFID signature stored in memory. FIG. 3 b depicting a plurality of transponders in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, and/or modulation. FIG. 4 a illustrates a letter hand printed on the sheet of FIG. 3 a . A hand held writing instrument such as an alternate pencil 161 can be used to write on the sheet in a process that mechanically removes the RF interfering layer as illustrated in FIG. 5 e to create altered blocked sheet 157 b having the hand written letter “R” 159 written thereon. Thus alternate exposed first antenna 151 b is cleared to be able to produce its unique RF signature and alternate exposed second antenna 155 b is cleared to be able to produce its unique RF signature. Similarly, all antennae that wee written upon are cleared to produce their respective RFID signatures which are stored in a database together with their respective positions on the substrate sheet. Note that blocked third antenna 153 can not produce its unique RFID signature. Similarly, all antennae that were not written upon, are still not able to produce their respective RFID signature. FIG. 4 a depicting a plurality of transponders or tags in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures has been altered by a user writing indicia whereby RFID detectibility, intensity, frequency, and/or modulation has been altered in the writing of the indicia. FIG. 4 b illustrates an RIFD sensed map of the letter of FIG. 4 a and the sensing process. Exposed antennae are able to produce their individual respective RF signatures including the first unblocked antenna 151 b , and the second unblocked antenna 155 b . Unexposed antennae still remain blocked from producing their RFID signatures including the third blocked antenna 153 . The processes of converting the altered antennae into meaningful data o control processes is the same as that described in FIG. 2 b . FIG. 4 b depicting a plurality of transponders or tags in array whereby some are RFID readable and have a signature corresponding to one stored in memory. FIG. 4 b further depicting a plurality of transponders or tags in array whereby RFID signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, modulation pattern. FIG. 4 b also depicting an RFID process whereby a plurality of RFID signatures are sensed by an RFID reader, the signatures that are sensed are compared to those in memory and are mapped to specific relative predefined positions in memory to establish which areas of the substrate sheet have been altered and which have not been altered. A map of altered or unaltered signatures is then compared to indicia stored in memory such as is common with OCR software and processes. The read RFID altered signatures thereby being converted to hand written or typed data read using RFID processes and converted to data for storage in memory and use is processes. FIG. 5 a illustrate a sheet of arrayed RFID tags each having a unique signature with printed indicia and a selection made. An example of an application of the present invention is a routing ticket for a passenger or merchandise. The ticket can have words printed upon it such as a first destination and selection boxes such as non-selected box 167 and selected box 163 . The status of the ticket can be remotely sensed using RFID techniques known in the prior art. During the processing of the sensing and processing steps according to FIG. 2 a , the area on the ticket which is perforated will be sensed as an altered part of the map since the antennae in that area have been physically removed or destroyed. FIG. 5 b illustrates a side view of a small section of FIG. 1 a . The second antenna 123 may protrude above the surface of the substrate so as to be easily written upon such that indicia electrically communicates with it or it can easily be destroyed in the writing process as in FIG. 5 c. FIG. 5 c illustrates a side view of a small section of FIG. 1 b . The alternate first antenna 123 b has been physically broken by the writing process (as compared to FIG. 5 b ) which alters or destroys its RF signature from that possible in FIG. 5 b. FIG. 5 d illustrates a side view of a small section of FIG. 3 a . The RF signature blocking layer 181 covers the blocked antennae including second blocked antenna 155 . Between antennae may be a inert substrate 171 . FIG. 5 e illustrates a side view of a small section of FIG. 3 b . The second exposed antenna 155 a can produce an RFI signal that can be read after the extracted blocking layer 181 a has been removed in the writing step. FIG. 5 f illustrates a side view of a small section of FIG. 3 a in an alternate embodiment. In some applications, blocking the RFID signal may require use of an additional bottom RF blocking layer 173 to insulate the antennae from producing signatures. FIG. 5 g illustrates a side view of a small section of FIG. 1 b in an alternate embodiment. The compressed first antenna 123 c has been physically broken by the writing process (as compared to FIG. 5 b ) which alters or destroys its RF signature from that possible in FIG. 5 b . The physical shape was facilitated by an altered substrate 127 a which comprises a material that compresses when written upon such that antennae thereon are altered in the writing or printing processes. Second Embodiment Multiple RFID Signatures with Common Antenna Comprise One Tag or Transponder FIG. 6 a illustrates a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a detectible format. A first RFID chip 321 is one of a plurality of chips arrayed upon a first multi-chip substrate 329 . A second RFID chip 323 is one of the plurality of chips arrayed on the first multi-antennae substrate. When subjected to a predetermined electromagnetic field, the first RFID chip is engineered to emit a first signature characterized by a first combination of frequency, intensity, and modulation pattern. When subjected to a predetermined electromagnetic field, the second RFID chip is engineered to emit a second electromagnetic signature characterized by a second combination of frequency, intensity, and modulation pattern. The first signature and the second differ from one another. Both the first RFID chip and the second RFID chip are electronically in communication with a common antenna 325 according to processes well know and widely practiced in the art. The first RFID chip and the second RFID chip being engineered to correspond with a transceiver using a predetermined protocol and an example of a chip that could be used is the so called “mu-chip” from Hitachi, Ltd. The chips are affixed to the substrate in a manner such that when written or printed upon, their ability to emit their predetermined signature is altered. For example, a user may use a pencil to write on the substrate according to FIG. 6 b such that the signatures of chips being physically written upon are altered by the writing process. The first multi-chip substrate comprising a material that can accept written indicia from a printer, pencil, pen or other indicia producing mechanism. Both the first RFID chip and the second RFID chip are electrically in communication with a second half of a common antenna 325 according to processes well know and widely practiced in the art. While the embodiment of FIG. 6 a comprises chips which are connected to two sides of an antenna it should be understood that many other antenna configurations are possible. A plurality of antennae and associated RFID chips are also present on the first multi-chip substrate. As discussed in previous figures, the physical position of a plurality of signatures is known and stored in a memory for later plotting of an altered signature map according to the process of FIG. 2 b . Whereas in previous figures, the each RFID chip had its own antennae, in FIG. 6 a , each antenna has a plurality of chips in respective communication therewith FIG. 6 b illustrates the elements of FIG. 6 a with indicia printed thereon. A user has used a pencil to physically write a first multi-chip altering “R” character 331 . The physical writing process has caused a number of RFID chips to be removed from the first altered multi-chip substrate 329 a and thereby altering the removed chips' respective ability to produce their respective predefined signature. FIG. 6 c illustrates the signature map of the elements of FIG. 6 b when being sensed using RFID and plotted against a map in memory. Using the processes according to FIG. 2 b and FIG. 9 , a transceiver will sense all of the unaltered signatures on the FIG. 6 b substrate. These unaltered signatures will be mapped against a map of the original unaltered signatures of each RFID chip in array in FIG. 6 a . A computer processor will generate a map similar to that is 6 c comprising areas where no unaltered signatures were detected including the first signature from the first RFID chip 321 a of FIG. 6 a . The generated map will also comprise areas where altered signatures were detected or where no signatures were detected such as first RFID chip array area of altered signatures 335 . Note that the signature from the second RFID chip was not detected and is absent from the map since the chip's ability to emit its signature was altered in the writing process described in FIG. 7 b . The shape of 335 will be one determining factor that the character recognition processes according to FIG. 2 b and FIG. 9 utilize in changing the map into usable and search data to support subsequent processes. FIG. 7 a illustrates a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a non-detectible format. A first isolated RFID chip 341 is one of a plurality of chips arrayed upon a second multi-chip substrate 349 . A second isolated RFID chip 343 is one of the plurality of chips arrayed on the second multi-antennae substrate. When subjected to a predetermined electromagnetic field, the first isolated RFID chip is engineered to emit a first signature characterized by a first combination of frequency, intensity, and modulation pattern. When subjected to a predetermined electromagnetic field, the second isolated RFID chip is engineered to emit a second electromagnetic signature characterized by a second combination of frequency, intensity, and modulation pattern. The first signature and the second differ from one another. Neither the first isolated RFID chip nor the second isolated RFID chip are not electrically in communication with an isolated common antenna 345 thus they are not able to produce their respective detectible signatures until the are connected in an indicia production step according to FIG. 7 b . The first isolated RFID chip and the second isolated RFID chip being pre-engineered to correspond with a transceiver using a predetermined protocol and an example of a chip that could be used is the so called “mu-chip” from Hitachi, Ltd. The chips are affixed to the substrate in a manner such that when written or printed upon, the are connected to the isolated antenna thus their ability to emit their predetermined signature is altered (in this case altered from undetectable to detectible). For example, a user may use a pencil pen printer or other device to write on the substrate according to FIG. 7 b such that the altered chips that are written upon are electrically connected to the isolated antenna. The second multi-chip substrate comprising a material that can accept written indicia from a printer, pencil, pen or other indicia producing mechanism, the prior art including some references herein describing such. Returning to FIG. 7 a , both the first isolated RFID chip and the second isolated RFID chip are electronically isolated from a second half of a common isolated antenna 347 (until one is written upon as in FIG. 7 b ). While the embodiment of FIG. 7 a comprises chips which are connected to two sides of an antenna it should be understood that many other antenna configurations are possible. A plurality of antennae and associated RFID chips are also present on the second multi-chip substrate. Each of the chips on the second multi-chip substrate are electronically isolated from contact with any antennae in FIG. 7 a until some are selectively electrically connected as a result of the writing of indicia according to FIG. 7 b . As discussed in previous figures, the physical position of the entire plurality of RFID chip signatures is known and stored in a memory for later plotting of an altered signature map according to the processes of FIG. 4 b and FIG. 9 . Whereas in FIG. 6 a , each (and all) of the RFID chips were placed upon the first substrate in electrical communication with at least one respective antennae, in FIG. 7 a , each (and all) of the RFID chips are placed upon the second substrate in electrical isolation from any of the antennae. FIG. 7 b illustrates the elements of FIG. 7 a with indicia printed thereon. A user has used a printer to physically write a first multi-chip altering “D” character 331 . The physical writing process has caused a number of RFID chips to be electrically connected to an antenna on the second altered multi-chip substrate 349 a and thereby altering the electrically connected chips' respective ability to produce its predefined signature, such that those chips that have been printed upon can emit their signatures through printed antenna connections while those chips that have not been printed upon still are not able to transmit their signatures due to having no antenna connection. FIG. 7 c illustrates the signature map of the elements of FIG. 7 b when being sensed using RFID and plotted against a map in memory. Using the processes according to FIG. 4 b and FIG. 9 , a transceiver will sense all of the altered signatures on the FIG. 7 b substrate. These altered signatures will be mapped against a map of each RFID chip in array in FIG. 6 a . A computer processor will generate a map similar to that in 7 c comprising areas where no signatures were detected such as no mapped signatures area 353 which includes a blank section corresponding to the position of the first isolated RFID chip 341 of FIG. 7 a since this chip was not written upon, it remains electrically isolated from an antenna and its signature intensity is essentially zero. The generated map will also comprise areas where altered signatures were detected (that is to say the intensity of their respective signals have been altered from a zero state to a detectible non-zero state). Map representation of altered signatures include second isolated RFID chip signature 343 a which is among the signatures which have been altered to be detectible as a result of the indicia writing process in FIG. 7 b and its position in the map corresponds to the position of the second isolated RFID chip on the second substrate of FIG. 7 a . The shape of the detected chip area will be one determining factor that the character recognition processes according to FIG. 2 b and FIG. 9 utilize in translating the map into usable and searchable data to support subsequent processes. FIG. 8 a illustrates a side view of a RFID free form label with indicia printed thereon and stuck to the side of a parcel. A parcel 301 has been diverted from its distribution route by a worker in the distribution system due to water damage. The parcel has a unique identifier EPC tag 303 which identifies it as distinct. The worker has completed a supplemental RFID writable label 305 according to the art described in this invention. The worker hand writes the EPC code from the EPC label onto the supplemental RFID writable label in an EPC writable section 307 of the supplemental tag. Thus when the supplemental label is read subsequently, a character recognition program will identify the EPC code written thereon as part of the record associated with the original EPC tag and parcel. The worker also hand wrote the reason for diversion in the free form field section 301 of the supplemental tag as “Water Damaged”. A checked box 309 on the supplemental label represents a predefined area on the label where if any detectible alteration occurs, a predefined process step will be executed. In this illustration, the parcel will be shipped back to the manufacturer for refurbishing. All of the written characters in FIG. 8 a will be sensed and processed according to FIG. 9 to convert hand written indicia into usable data that is used in processes. The predefined area, namely the checked box doesn't require any character recognition step. Any signature alteration in the predefined area section of the writable tag (or memory alteration according to FIG. 11 ) will result in a predefined process step such as is detailed in an initiate altered signature process 243 of FIG. 9 . This is because the signature map that is stored in memory includes specific instructions that are invoked when specific altered signatures are sensed in the RFID sensing process. FIG. 8 b illustrates a top view of a RFID free form label with indicia printed thereon and stuck on an envelope. A paper envelope 313 has been labeled using an RFID readable free form field hand writable label 315 according to the present invention. The RFID readable free form field hand writable label includes a predefined zip code box 319 that is a special area defined in memory where a number sensed in the RFID altered signature sensing process is known to be part of a zip code. In the freeform field section, the address 317 is hand written. After the label is hand written or typed upon, it is completely covered by a thin plastic film (not shown) which is adhered to its surface to protect the label from further alteration. When this envelope is mailed, the processes of FIG. 9 will be used to turn the hand written indicia into meaningful alpha numeric character data for properly routing the envelope autonomously. The address label may have a unique identifier RIFD signature associated with it to distinguish it from other envelopes. FIG. 9 illustrates a process flow chart of sensing altered RFID signatures and for converting sensed signatures of written indicia into data. The flow chart of FIG. 9 and the discussion of it is applicable to many steps and processes described in the preceding diagrams and is also applicable to the processes of hand writable or printable memory and ensuing character recognition according to FIGS. 10 , 11 , and 12 and the discussion of them. FIG. 9 depicts processes and steps including the following discussion, some of which are required and others of which are optional. A produce RFID tag comprising a plurality of RFID signatures in array process 201 is first undertaken according to the preceding FIGS. 1 through 8 b . A comparable process relating to FIGS. 10 , 11 , and 12 would be the production of a physical memory substrate and then the integration of it with an RFID device such as a tag or transponder. In the manufacturing process a create predefined field in proximity to manufacture printed indicia step 203 may be undertaken. If undertaken, this step entails a printing of indicia on the tag during the manufacturing process and defining these areas in memory during a memory storage process 207 discussed later. Examples of predefined fields in proximity to manufacture printed indicia includes the predefined check box and hand writable EPC fields of FIG. 8 a and the predefined zip code fields of FIG. 8 b . The manufacture printed indicia is a visible queue to assist a worker in a subsequent step or process to place information on the tag in a predefined position (predefined in memory and a physical position on the substrate) as described such that information placed on the tag in relation to the manufacture printed indicia can be efficiently interpreted and be used in a process. The manufacturer printed indicia step can be applicable to all three embodiments herein. Whether the tag has manufacture printed indicia or not, it may come from the manufacture with detectible RFID signatures after a signatures enabled step 205 or it may come from the manufacturer with un-detectible signatures after a signatures not enabled manufacturing process 205 a . (In either case it may also have a readable unique identification signature that is distinct.) The former is described in FIGS. 1 a - 2 b , and 6 a - 6 c , and the later is described in FIGS. 3 a - 4 b and 7 a - 7 c . It should be noted that these figures and associated descriptions can be utilized with the third embodiment described herein which as described as coming from the manufacturer with memory connections not made but might also be manufactured with memory connections made and whereby during the user writing indicia process, memory connections are severed as the alteration step that will form the basis of comparison when performing the character recognition or predefined processes steps of FIG. 9 . An initial storage in memory process 207 prepares the memory for subsequent processes of FIG. 9 and throughout all three embodiments. The initial storage in memory process may contain multiple storage steps and storage of multiple types of information. A list of unique identifiers associated with each individual free form field writable tag may be stored in memory. A list of defined signatures may be stored in memory according to the first and second embodiment. A map of defined signature positions on the substrate may be stored in memory according to the first and second embodiment. A library of prospective indicia including characters and words may be stored in memory to support character recognition processes in the first, second and third embodiments for the purpose of converting RFID sensed patterns into meaningful data that can be used in subsequent processes via the converting of sensed patterns involving their comparison to the library of prospective indicia initially stored in memory. A list or map of predefined signatures for the first and second embodiments and of positions on respective substrates in all the three embodiments may be stored in memory where they represent fields associated with manufacture printed indicia. Predefined processes associated with the manufacture printed indicia may be stored in memory whereby alterations to predefined areas will invoke the predefined processes from memory. Examples of processes which are stored in memory in connection with a manufacture printed indicia are the predefined check box and hand writable EPC fields of FIG. 8 a and the predefined zip code fields of FIG. 8 b . Stored in memory in connection with the checked box is a process including instructions to return the parcel to the manufacturer if the box is checked. Whether the box is checked can be determined by RFID sensed data patterns including predefined signature alterations in the first two embodiments and a predefined memory readout pattern according to the third embodiment. Stored in memory in connection with the manufacturer printed hand writable EPC input fields is a process to consider alphanumeric characters hand written into this field to be part of a unique EPC code. In the first second and third embodiments Processes stored in memory may be in connection with characters that are recognized during a character recognition step or processes may be stored in memory in connection with their physical locations on the respective substrates. The zip code fields of FIG. 8 b being an example of the former and the checked box of FIG. 8 a being an example of the later. The process invoked by the former being routing of an envelope and the later being an example of a parcel routing process. It is note worthy that the memory contemplated in this initial storage in memory process is a remote memory connected to a network that contains data about the tagged item and typically tracks items through business processes but the memory that is loaded in this initial storage in memory process may also comprise memory storage on the tag itself which is accessible through RFID. Each of the three embodiments described herein comprise a step of alteration as the means to convey meaningful information. The first two embodiments involve the alteration of predefined RFID signatures with respect to any of detectibility, intensity, frequency, or modulation pattern. The third embodiment involving the alteration of memory locations (connections) from an “off” state to an “on” state or from an “on” state to an “off” state. Several means exist in the prior art for altering including hand processes 211 such as writing with a pencil or pen, machine processes 213 such as using a printer to print electrically conductive ink, and other processes 215 such as a paper punch severing a portion of the tag. In any case, alteration of the tag's composite RFID signature results from the alteration step. Additionally, the alteration step may involve user creation of alphanumeric text 217 , indicia 219 , a filter 221 , or detachment of a portion 223 of the tag. As discussed, the alteration process in the first two embodiments involve the alteration of predefined RFID signatures step 225 with respect to any of detectibility alteration step 229 , intensity alteration step 233 , frequency alteration step 227 , or modulation pattern alteration step 231 . The third embodiment involving the alteration of memory from an “off” state to an “on” state or from an “on” state to an “off” state the alteration being communicated via the modulation pattern alteration step 231 . Each of the three embodiments involve an RFID sensing process 235 . Using well known active or passive emitting processes, sensing processes, protocols, and querying and responding strategies altered information is transferred from the tag to a transceiver. In the first two embodiments, part of the RFID sensing process will involve sensing a first signature, sensing a second signature, and sensing all signatures until the final or Nth signature from a tag is sensed. In the third embodiment, part of the RFID sensing process may involve sensing a binary modulation pattern that is indicative of alterations to the writable and erasable physical indicia memory of FIGS. 10-12 b whereby bits that are written upon are 0's and areas that are not written upon are 1's. In the first two embodiments, a comparator process 237 is performed whereby the 1 st sensed signature is compared to signatures defined in memory to determine if sensed signatures match signatures in memory. In an iterative process the first sensed signature is compared to those in memory, the second sensed signature is compared to those in memory, and all sensed signatures are similarly compared to memory including the last or Nth sensed signature. A notation is made in memory of those signatures that are sensed and matched to ones in memory in a store sensed signatures in memory step 239 . In the third embodiment, the modulation of 1's and 0's from the tag representative of whether and where user alteration of the tag has occurred is stored in memory in the store sensed signatures in memory step 239 . The short path to transforming sensed information into business process invocation comprises two steps including a specific missing or altered signature step 241 where a specific area on a respective substrate has been altered and that altered area is associated with a specific predefined process in memory in which case an initiate altered signature process 243 is initiated. A special case of these two steps is the case including a detectible altered signature step 241 a where signatures in the original substrate were not detectible before being user altered such as is the case with FIGS. 3 a through 4 b and 7 a through 7 c . In this case an initiate detectible signatures process 243 a is commenced where a specific area on a respective substrate has been altered and that altered area is associated with a specific predefined process in memory. The longer path to invoking processes comprises the recognition of characters using altered signature as a proxy in the first two embodiments and using alter modulation patterns from memory connections as a proxy in the third embodiment. A plot sensed defined signatures against a map in memory process 245 is performed when user printed indicia is to be converted into readable data In the first and second embodiments, this involves plotting sensed signatures into a map of where their associated emitters are respectively positioned upon their respective substrate. The sensed signature map will comprise areas where signatures have been altered and areas where signatures have not been altered. Shapes of the altered areas can then be compared to the indicia or character library in memory in a subsequent character recognition step. In the third embodiment the plot sensed defined signatures against a map in memory process 245 is performed when user printed indicia is to be converted into readable data and it involves plotting sensed 1's and 0's into a map of where their associated memory contacts are respectively physically positioned upon their respective substrate. The resulting map of sensed memory contacts will comprise areas where memory contacts have been altered (where electrical contacts have been connected or disconnected) and areas where memory contacts have not been altered. Shapes of the altered areas can then be compared to the indicia, word, or character library in memory in a subsequent character recognition step. In any case, the resulting plotted map may be stored in a store sensed map in memory step 247 . In all three embodiments, where user alterations are to be converted to recognized characters or indicia, a compare plotted sensed signatures to recognized indicia, character, or word library in memory step 249 is under taken. This process is identical to well known optical character recognition (OCR) processes except that whereas OCR utilizes optical scanning to acquire an image map and the image map represents visual indicia on a substrate, the present invention uses a mechanism such as alteration of signatures or memory connections on a substrate as a proxy for an image and they are communicated through RFID to acquire an image map. The comparator process herein is otherwise the same as OCR. Thus in the present invention, a step where indicia is recognized 251 occurs. In a store sensed and recognized indicia in memory step 253 , indicia that was placed on the substrate by a user, transmitted through a proxy indicator using RFID, mapped, and compared to recognized indicia, has been recognized, and is then stored in memory as useable and searchable data. The data can then be the basis for business processes including key word searching of memory processes 259 , and an accessing recognized sensed indicia processes from memory step 255 . The recognized data can be used to initiate recognized sensed indicia processes 257 . Third Embodiment Physical Indicia Based Memory and RFID Facilitated Character Recognition FIG. 10 illustrates a simple circuit that can serve as a writable and erasable physical indicia based memory and sensor. A user writeable and erasable physical memory 401 comprises a number of open circuit connections comprising two sides of a circuit including a raised contact point 405 that is on a first side of the circuit including a column 403 . The raised contact point being one of a plurality of similar raised contact points which are arrayed to be electronically isolated from one another and from the second side of the circuit except when addressed by a flip-flop array including a first flip-flop 404 through an iterative process controlled by a pulse timer 402 . On the second side of the circuit is a raised contact line 407 which is one of a plurality of similar raised contact lines in array. The raised contact lines are electrically isolated from the raised contact points exception when connected by the writing of indicia according to FIG. 11 . The raised contact lines are in electrical communication with a serial shift register 411 which in operation in FIG. 11 produces a serial data stream 409 that describes which contacts (or memory locations) are connected by the writing of indicia and which are not connected. The shift register can also be seen in FIG. 12 b . In practice, the user writeable and erasable physical memory 401 is integrated with a substrate (not shown) such as a paper product that has an upper surface essentially equal to the height of the raised contact points and raised contact lines. The user writeable and erasable physical memory is integrated with a tag or transponder according to FIG. 12 a or 12 b to enable a tag that can receive written indicia comprising electrically conductive material that concurrently connects the raised contact points to raised contact lines. Prior to receiving written indicia, the user writeable and erasable physical memory is read as all 1's since no contacts between raised contact points and raised contact lines have been made. After a user writes indicia upon the substrate and thereby connects selected raised contact points to raised contact lines, the user writeable and erasable physical memory is read as a serial combination of 1's where no connection has been made and 0's where connections have been made and these 1's and 0's are a proxy indicator describing where indicia is written upon the substrate and they are transmitted through the FIG. 12 a or 12 b RFID architecture according to FIG. 9 and FIG. 11 and selectively subjected to processes described therein. The processes to alter select RFID signatures 209 of FIG. 9 and related discussion herein is applicable to the user writeable and erasable physical memory. The 1's and 0's transmitted being transmitted in sequence and the 0's representing altered memory connections. If the user writeable and erasable physical memory is written upon with a pencil or erasable ink, indicia written thereon can be erased as can the electrical connections the indicia made. The user writeable and erasable physical memory can be scaled to be nearly any size and resolution using well known principles and available electronic circuitry, the version described in FIG. 11 being significantly larger and having a higher resolution (number of raised contact points per inch). Also, while the user writeable and erasable physical memory version depicted in FIG. 10 begins with all contacts open, it could just as well begin with all contacts closed similarly to the discussion of FIGS. 7 a - 7 c whereby during the writing process, memory contacts are severed and that comprises the alteration step that will form the bases of comparison when performing the character recognition or predefined processes steps of FIG. 9 . FIG. 11 illustrates a process for communicating indicia stored in written form according to FIG. 10 and for sensing indicia and translating the indicia to data to be utilized in additional processes. A high resolution user writeable and erasable physical memory substrate 401 a has “DoD” indicia written thereon and is integrated with an indicia memory enhanced RFID transponder tag 413 according to FIG. 12 a or 12 b . When caused to do so by a transceiver, the indicia memory enhanced RFID transponder tag 413 produces a transmission 415 which comprises the 1's and 0's corresponding to contacts made by the “DoD” indicia written thereon and which is received by the high resolution user writeable and erasable physical memory substrate transceiver 417 . A map of received memory contacts 423 can be saved in a transceiver connected memory 427 . A processor 421 will perform a character recognition process 421 where the map of received memory contacts 423 is compared to a character library 429 . A contact connections mapped 435 is indicative of one connection on the high resolution user writeable and erasable physical memory substrate 401 a that has been made, transmitted, received, and mapped according to the order received through an altered modulation pattern comprising 1's and 0's presented in the order they are iteratively addressed by the integrated circuit according to FIG. 10 . Recognized characters 425 are stored in memory as data which can be subjected to a data search or business process step 431 . Integrated character recognition 433 can alternately be integrated directly with the high resolution user writeable and erasable physical memory substrate if desired. Also, An intermediary tag 430 comprising an intermediary memory 434 may also be utilized if desired. An intermediary tag might be useful where supplemental data is to be added to a primary tag such as was described in FIG. 8 a . In which case intermediary primary and secondary transmission 432 and intermediary primary and transceiver transmission 436 are utilized. FIG. 12 a illustrates an RFID transponder or tag formed by a simple circuit integrated with the indicia memory circuit according to FIG. 10 . An integrated writable and erasable physical indicia memory 401 b according to FIGS. 10 , and 11 , is integrated with a simple transponder circuit 413 a comprising a modulator 435 which is utilized to modulate the status of each respective raised contact point of FIG. 10 in a predetermined order so as to me mapped according to FIG. 11 as a proxy for indicia written upon a substrate which makes electrical contacts to physical memory positions according to FIGS. 10 and 11 . An EEPROM 437 may be in the circuit to communicate unique identifier information but this need not be the case. A separate power supply 439 may be provided depending upon the size, energy requirements, and other characteristics of the integrated writable and erasable physical indicia memory 401 b . In an alternate approach, an intermediary integrated transponder 401 b may transmit an intermediary integrated transponder signal 443 in lieu of a direct connection the simple integrated transponder circuit 413 a. FIG. 12 b illustrates an RFID transponder or tag formed by a circuit architecture common to Texas Instruments RFID devices integrated with the indicia memory circuit according to FIG. 10 . A Texas Instruments writable erasable physical indicia enhanced memory transponder 467 comprises the circuitry and processes to enable the art of FIGS. 10 , and 11 to work effectively as a transponder with writable erasable physical indicia enhanced memory. An end of burst 451 is sensed which causes an oscillator 453 to initiate a clock driver 455 to begin a modulation 463 according to a shift register 465 which facilitates the readout of data from a WEPIM 401 c (writable erasable physical indicia memory). A tuner 461 facilitates the oscillation with the transceiver (not shown). A discharge step 457 is provided to ensure the transponder is properly prepared for the next communication session with the transceiver. A voltage regulator 459 is in connection with a coil 467 which modulated to report the digital data from the WEPIM. An augmented power supply 439 may be provided if needed. Operation of the Invention Operation of the invention has been discussed under the above heading and is not repeated here to avoid redundancy. Conclusion, Ramifications, and Scope Thus the reader will see that the Configurable RFID Apparatus and Process of this invention provides a novel unanticipated, highly functional and reliable means for employing RFID techniques in a freeform RFID tag that comprises a plurality of smaller tags that can be used to capture as data a wide range of printed or written indicia which in turn can be used to drive an unlimited variety of processes. While the above description describes many specifications, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of a preferred embodiment thereof Many other variations are possible for example: The description herein illustrates the invention in a passive RFID tag, but it is understood to also be useful in active RFID tag systems. A few applications are described herein but it should be understood that the applications of the present invention are virtually limitless. Each RFID signature in the plurality of signatures arrayed on a substrate sheet can be truly unique. Alternately, the substrate sheet may have a single unique identifier signature with all of the other signatures being standard for the class of substrate sheets. The memory may store two signatures for each detectible devices whereby a user is able to alter a select combination of devices between their respective two sets of signatures such that each devices remains detectible in a predictable manner even after its signature has been altered. Audible or inaudible sound waves can be substituted for electromagnetic radiation energy as the medium to both excite a remote tag and to be sensed by the transponder and transceiver. Means of altering the readability of individual antenna signatures to achieve the ends of rendering an antenna to be either readable, unreadable, or readable with an altered signature have all been described herein using methods of communicating electrically with an antenna or circuits associated with an antenna, blocking or unblocking the ability of an antenna or circuits associated with an to produce an RF signal, or destrying the ability of an antenna or circuits associated with an to produce an RF signal. It is anticipated that other means are possible for achieving similar ends. Also, while the description herein focuses on interacting with the antenna as a means to produce an RF altered map, it is understood that any element such as a circuit which is in communication with an antenna can also be similarly altered to achieve identical ends.
The invention described herein represents a significant advancement in user configurable and reconfigurable RFID readable data input. A writing substrate includes a wireless energy transmission circuit and a plurality of switchable contacts. When or after a user writes on the substrate, it can be sense remotely to produce a map of the writing which provides input a character recognition process. Thus a user can write anything they wish to create data and control processes on a cheap, disposable user interface.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "BACKGROUND 1.", "Field of Invention Packaging and containers are among the wide variety of applications where RFID (radio frequencies identification) transponders or tags are currently being used by the many hundreds of millions.", "The highest volumes of tags generally comprise a passive antenna and unique signature identifier chip integrated within a product or packaging which in operation, can be detected at points within the product distribution cycle.", "When data associated with the product is to be accessed, the product tag is caused to resonate a signature that is distinguishable from others when compared to a database of resonation signatures.", "The matching signature within the database then is used to call up details from the database about the product associated with the sensed tag signature.", "Active RFID tags are also known which operate similarly to passive RFID tags except that they are integrated with a power source to enhance transmission of information.", "Description of Prior Invention The vast majority of prior art relates to passive RFID tag systems where an individual item has an individual tag with and individual unique signature associated with it.", "The individual tag will stay with the item through a portion of the distribution cycle and generally not be altered during the distribution cycle except possibly when the product moves out of the distribution system (is purchased by a customer) at which time the RFID tag may be deactivated in some instances.", "Some prior art describes RFID tags that can be altered by a worker in the product distribution cycle to customize information about the product.", "For example, U.S. Pat. No. 4,889,961 (Carlson) describes a process whereby a worker draws a line with a conductive material which completes a circuit as a mechanism to customize and alter the information communicated by an RFID tag.", "Similarly, U.S. Pat. No. 6,805,291 (Chhatpar et al) describes a process whereby a worker can utilize a writing instrument such as a pencil, printer, and/or eraser to connect and disconnect circuits associated with an RFID tag to modify the RFID signature of the tag.", "The process of modifying an RFID circuit using a writing instrument such as a pencil, eraser, and/or printer being further described in U.S. Pat. No. 6,840,444 (Pierce et al), U.S. Pat. No. 6,869,020 (Foth et al), and U.S. Pat. No. 6,869,021 (Foth et al).", "The prior art described in this paragraph generally representing examples of configurable or reconfigurable RFID tags using connectable and disconnectable contacts and associated circuits whereby the individual signatures of individual tags are configured or reconfigured to represent information.", "BRIEF SUMMARY The invention described herein represents a significant advancement in use configurable and reconfigurable RFID readable data by the introduction of RFID readable free form sheets of a plurality of RFID signatures that are alterable by a user.", "Freeform sheets are a novel basis for enabling hand written or printed text to be read using RFID techniques according to a process such as the following preferred embodiment.", "A plurality of individual RFID transponder signatures is arrayed on a substrate sheet.", "Each transponder in the plurality has a unique signature and a known physical position on the substrate which is stored as a map in a memory.", "Each unique signature is user alterable with regard to changing detectibility, frequency, intensity, and/or modulation.", "Using a writing instrument such as either a pen, an eraser, or a printer, the user interacts with the sheet to alter some of the unique tags for example by writing a word on the sheet.", "The sheet is then read using RFID techniques such that each individual tag that produces an altered or unaltered readable signal is sensed, registered, and plotted against the map of the sheet in memory using the predetermined positional relationships of the individual signatures in the array.", "This sensed map is then interpolated using automatic charter recognition software to convert the map into alpha numeric data which is stored in a database or used in determining the routing or processing of the sheet and/or the article or product associated with the sheet.", "Thus user alteration of individual unique signatures on the freeform sheet forms the basis of communicating data in the form of a map of altered and unaltered individual unique tags that are interpolated using character recognition software into meaningful hand written words, printed words, alphanumeric characters, diagrams, or indicia that can be stored in a database, and or used for processing the sheet and/or an item associated with the sheet.", "Thus the present invention offers a significant advancement in the ability to communicate an unlimited range of information on a single freeform RFID readable sheet.", "Objects and Advantages Accordingly, several objects and advantages of the present invention are apparent.", "It is an object of the present invention to provide a means to reliably and inexpensively communicate a very wide range information using an RFID technique.", "It is an object of the present invention to provide an RFID freeform field where data can be written in by hand and automatically be stored in a database as alphanumeric data associated with an object, a product, or a person.", "It is an object of the present invention to provide an RFID freeform field where data can be printed in and automatically stored in a database as alphanumeric data associated with an object, a product, or a person.", "It is an object of the present invention to provide an RFID freeform field where data can be erased by hand and automatically be altered in a database as alphanumeric data associated with an object, a product, or a person.", "It is an advantage that a user can communicate information without the need of special equipment.", "It is an advantage of the present invention that a user can write words on a medium that are RFID readable.", "It is an advantage of the present invention that hand written words can be converted to data autonomously and without the need for special equipment.", "It is an advantage of the present invention that it can utilize nearly any transponder chip, circuit, and antenna that is known in the RFID industry.", "For example where multiple chips are utilized with individual antennae, and where multiple chips are utilized with a common antennae, the so called “mu-chip”", "from Hitachi, Ltd. can be utilized with the present invention.", "It is an advantage of the present invention that it can utilize nearly any reader that is known in the RFID industry.", "It is an advantage of the present invention that it can utilize many reading approaches such as ALOHA, tree walking or binary tree, FDMA, and CDMA.", "It is an advantage of the present invention that each RFID signature in the plurality of signatures arrayed on a substrate sheet can be truly unique.", "Alternately, the substrate sheet may have a single unique identifier signature with all of the other signatures being standard for the class of substrate sheets.", "Further objects and advantages will become apparent from the enclosed figures and specifications.", "DRAWING FIGURES FIG. 1 a illustrates a sheet of a plurality of exposed arrayed individual unique signature RFID transponders.", "FIG. 1 b illustrates the sheet of FIG. 1 a with a word printed thereon.", "FIG. 2 a illustrates a letter hand printed on the sheet of FIG. 1 a. FIG. 2 b illustrates an RIFD sensed map of the letter of FIG. 2 a and the RFID sensing process.", "FIG. 3 a illustrates a sheet of a plurality of covered arrayed individual unique signature RFID transponders.", "FIG. 3 b illustrates the sheet of FIG. 3 a with a word printed thereon.", "FIG. 4 a illustrates a letter hand printed on the sheet of FIG. 3 a. FIG. 4 b illustrates an RIFD sensed map of the letter of FIG. 4 a and the RFID sensing process.", "FIG. 5 a illustrate a sheet of a plurality of arrayed RFID tags each having a unique signature with printed indicia and a selection made.", "FIG. 5 b illustrates a side view of a small section of FIG. 1 a. FIG. 5 c illustrates a side view of a small section of FIG. 1 b. FIG. 5 d illustrates a side view of a small section of FIG. 3 a. FIG. 5 e illustrates a side view of a small section of FIG. 3 b. FIG. 5 f illustrates a side view of a small section of FIG. 3 a in an alternate embodiment.", "FIG. 5 g illustrates a side view of a small section of FIG. 1 b in an alternate embodiment.", "FIG. 6 a illustrates a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a detectible format.", "FIG. 6 b illustrates the elements of FIG. 6 a with indicia printed thereon.", "FIG. 6 c illustrates the signature map of the elements of FIG. 6 b when being sensed using RFID and plotted against a map in memory.", "FIG. 7 a illustrates a side view a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a non-detectible format.", "FIG. 7 b illustrates the elements of FIG. 7 a with indicia printed thereon.", "FIG. 7 c illustrates the signature map of the elements of FIG. 7 b when being sensed using RFID and plotted against a map in memory.", "FIG. 8 a illustrates a side view of a RFID free form label with indicia printed thereon and stuck to the side of a box.", "FIG. 8 b illustrates a top view of a RFID free form label with indicia printed thereon and stuck on an envelope.", "FIG. 9 illustrates a process flow chart of sensing altered RFID signatures and for converting sensed signatures of written indicia into data.", "FIG. 10 illustrates a simple circuit that can serve as a writable and erasable physical indicia based memory and sensor.", "FIG. 11 illustrates a process for communicating indicia stored in written form according to FIG. 10 and for sensing indicia and translating the indicia to data to be utilized in additional processes.", "FIG. 12 a illustrates an RFID transponder or tag formed by a simple circuit integrated with the indicia memory circuit according to FIG. 10 .", "FIG. 12 b illustrates an RFID transponder or tag formed by a circuit architecture common to Texas Instruments RFID devices integrated with the indicia memory circuit according to FIG. 10 .", "DETAILED DESCRIPTION OF THE INVENTION First Embodiment Multiple RFID Devices Comprise One Tag or Transponder FIG. 1 a illustrates a sheet of exposed arrayed individual RFID devices each having a unique signature.", "A first substrate 127 comprises a sheet such as paper upon which is affixed or otherwise deposited an array of RFID antennae such as a first antenna 121 which is connected to a first chip (not visible) and in operation produces a first RFID signature, a second antenna 123 which is connected to a second chip (not visible) and in operation produces a second RFID signature, and a third antenna 125 which is connected to a third chip (not visible) and in operation produces a third RFID signature.", "All of the dozens of individual RFID antenna of FIG. 1 a in combination with respective chips are capable of producing a respective individual RFID signature that differentiates it from others on the sheet.", "As described in FIG. 2 b , the positions of each respective transmitting antenna is known and its location on the sheet substrate together with its signature is stored in a database which is used in reading and interpreting changes made on the sheet.", "The 121 , 123 , and 125 comprising a plurality of devices on a substrate including a first device capable of producing a first signature, a second device capable of producing a second signature, and a third device capable of producing a third signature.", "FIG. 1 a depicting a plurality of transponders in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip.", "FIG. 1 b illustrates the sheet of FIG. 1 a with a word printed thereon.", "In a printing process, an RF interfering or otherwise electrically conducting ink is printed upon the surface of the first substrate sheet 127 including a first letter “D”", "129 .", "In a first alternative approach, the ink is deposited directly upon and has electrical communication with antennae and/or associated circuitry upon which it is printed so as to effectively short circuit or modify their respective RF signatures while not having electrical communication with antennae and/or associated circuitry upon which it is not printed and not altering their signatures.", "In a second alternative approach, the ink has an RF signal interfering or blocking effect on antennae and/or antennae circuitry upon which it is printed while not having an RF signal interfering or blocking effect on antennae and/or antennae circuitry upon which it is not printed.", "In ether case, the RFID signature of each antenna covered by ink in FIG. 1 b is altered from its original respective signature when it was not covered by ink as in 1 a .", "Thus a first altered antenna 121 a produces either no signature or an altered signature as compared to the first antenna 121 of FIG. 1 a and a second altered antenna 123 a produces either no signature or an altered signature as compared to the second antenna 123 of FIG. 1 a .", "Note that the third RFID signature produced by the third antenna 125 is not altered by the printing process since it is neither in electrical contact with the ink nor covered by RF interfering ink.", "The process described in FIG. 2 b will map the altered antennae compared to the unaltered antennae as a step to reading the words that have been printed upon the substrate sheet.", "It should be noted that the size of the antennae compared to the size of the sheet and the size of the print can be altered in scale such that a single letter may cover dozens of antennae to increase the resolution when read in the process of FIG. 2 b .", "Suitable inks and printing processes are know in the prior art some of which are reference in the above Prior Invention section.", "FIG. 1 b depicting a single transponder or tag which comprises a plurality of transponders or tags in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, and/or modulation.", "FIG. 2 a illustrates a letter hand printed on the sheet of FIG. 1 a .", "A writing instrument such as a pencil contains an electrically conductive or RF interfering composite including for example graphite which may also be erasable.", "Suitable hand writing instruments such as pencils, erasers, pens, and styluses are described in the prior art some of which is referenced in the above Prior Invention section.", "For antennae upon which the pencil writes, the RFID signatures are altered as described in FIG. 1 b .", "For antennae upon which the pencil does not write, the antennae RFID signatures are unaltered from those described in FIG. 1 a and in a database describing signatures and signature according to FIG. 2 b .", "Alternately, to alter the signature of select antennae, the writing instrument can be a stylus used to break the antennae or associated circuitry according to FIGS. 5 c and 5 g .", "Thus a first hand written letter “D”", "129 b is written upon the substrate sheet 127 whereby the RF signatures of covered (or partially covered) antennae are altered such as first hand instrument altered antenna 121 b , and second hand instrument altered antenna 123 b .", "Those antennae with altered signatures no longer match the signatures of the original sheet of FIG. 1 a and as further described in the reading described in FIG. 2 b reading and interpolating processes.", "Signatures of antennae that were not written on such as the third antenna 125 are not altered and are still capable of producing their original RFID signatures.", "FIG. 2 a depicting a plurality of transponders or tags in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures have been altered by a user writing indicia whereby RFID detectibility, intensity, frequency, and/or modulation has been altered in the writing of the indicia.", "FIG. 2 b illustrates an RIFD sensed map of the letter “D”", "of FIG. 2 a and the RFID sensing and interpreting processes.", "After being written on with a writing instrument or with a printer, the signatures of altered antennae and/or associated circuitry will not match those original signatures in a database 141 .", "Each antenna that can be read according to its original signature has a known signature and a known positional relationship such as the individual respective double-digit numbers in FIG. 2 b .", "In operation, an RF transmitter 133 emits energy that causes the unaltered antennae on the substrate sheet 127 to emit their specific signatures which are received by an RFID receiver 135 , the signatures are compared to a map in the database to form an altered signature map which can be displayed 137 .", "The map comprising spots (or pixels) on the sheet where received antennae signatures match those in the database such as the double-digit numbers including third antenna 125 .", "The map also comprising spots (or pixels) where the signatures of antennae at specific frequencies have not been received such as the first altered antenna 121 b and the second altered antenna 123 b .", "Such altered antennae being mapped as the printed or written indicia that was placed upon the sheet substrate in FIGS. 1 b , and/or 2 a .", "In order to convert the altered sheet map to data, an interpolator 139 compares the map to a database of known alphanumeric characters or other indicia to discern what the map says.", "Once the alphanumeric characters are interpolated, they can be stored in the database or displayed as text 143 on a screen.", "A vast number of processes 145 such as shipping, or distribution instructions can be executed by comparing a keyword list in the database to words that are interpolated from the sheet and stored in the database.", "For example, if the words written contain a zip code, keyword processes can automatically route a package associated with the sheet to the appropriate zip code written thereon.", "Thus a very wide range of hand written or printed information can be converted to executable data using the RFID technique described herein.", "The transmitter, receiver, database, and keyword processes being well known in the prior art.", "The interpolator 139 being virtually identical to those employed for optical character recognition (OCR) processes except with the advantage that whereas optical scanning of the sheet requires that an optical scanner be in a certain close tolerance proximity to the sheet, the RFID scanning technique can be employed from a far greater distance and tolerance than can optical scanning.", "The character recognition process herein utilizing a directory of indicia, alphanumeric characters, words, symbols, patterns, or physical relationships that can be used to compare against the sensed map for the purpose of identifying recognizable characters or content.", "Thus steps of the present invention may include;", "depositing a plurality of antennae upon a substrate sheet wherein each respective antenna (and associated chip) is capable of producing a respective RFID signature, storing in a database (or memory) the data describing the respective RFID signatures and a map of physical positions on the sheet of each associated respective antenna, the writing of indicia on the sheet of antennae that alters the properties of RFID signatures of some antennae (and associated chips) on the sheet, using RFID to sense antennae on the sheet, comparing sensed signatures information to possible signatures information in the database to produce an altered antennae map of the sheet, displaying of the altered antennae map, storing of the altered antennae map in the database, a character recognition step where the altered antennae map is compared with a database of characters to convert the map into alphanumeric or other indicia data, displaying of the alphanumeric or other indicia data, storing of the alphanumeric or other indicia data in the database, comparing the data to a database of possible data for the purpose of controlling processing of the sheet and/or a physical object associated with the sheet;", "and/or whereby a writing on the sheet is used to control processing of the sheet.", "FIG. 2 b depicting a plurality of transponders or tags in array whereby some are RFID readable and having a signature corresponding to one stored in memory.", "FIG. 2 b further depicting a plurality of transponders or tags in array whereby RFID signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, and/or modulation.", "FIG. 2 b also depicting an RFID process whereby a plurality of RFID signatures are sensed by an RFID reader, the signatures that are sensed are compared to those in memory and are mapped to specific relative predefined positions in memory to establish which areas of the substrate sheet have been altered and which remain unaltered.", "A map of altered or unaltered signatures is then compared to indicia stored in memory such as is common with OCR (optical character recognition) software and processes.", "The sensed RFID signatures thereby being used to convert hand written or typed indicia to recognized data for storage in memory and use is processes.", "FIG. 3 a illustrates a sheet of covered arrayed individual unique RFID devices each having a unique signature.", "A blocked antennae array sheet 157 is identical to the substrate sheet 127 of FIG. 1 a except that all of the antennae are blocked from producing their respective RF signatures stored in the database as further described in FIGS. 5 d , 5 e , and 5 f .", "A first blocked antenna 151 , a second blocked RF antenna 155 , and a third blocked antenna 153 are covered by a material such as a thin aluminum foil deposition so that their unique signatures can not be detected by the RFID process.", "FIG. 3 a depicting a plurality of transponders in array each being shielded from being RFID readable and having a unique signature and comprising a respective antenna and a respective chip.", "FIG. 3 b illustrates the sheet of FIG. 3 a with a word printed thereon.", "Indicia can be printed on the altered covered sheet 157 a such as a printed “R”", "159 .", "When the indicia is printed upon the 157 a , it destroys the blocking layer thereby exposing underlying antennae including a first exposed antenna 151 a , and a second exposed antenna 155 a .", "The exposure can be facilitated by a chemical process that destroys the ability of the blocking deposition from effectively blocking the RFID antennae signatures.", "Alternately, a mechanical process may be utilized such as is described in FIG. 4 a .", "In either case, the blocking property of material covering antennae which are not printed on, is not changed by the printing process including third blocked antenna 153 which can not produce the RFID signature stored in memory.", "FIG. 3 b depicting a plurality of transponders in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, and/or modulation.", "FIG. 4 a illustrates a letter hand printed on the sheet of FIG. 3 a .", "A hand held writing instrument such as an alternate pencil 161 can be used to write on the sheet in a process that mechanically removes the RF interfering layer as illustrated in FIG. 5 e to create altered blocked sheet 157 b having the hand written letter “R”", "159 written thereon.", "Thus alternate exposed first antenna 151 b is cleared to be able to produce its unique RF signature and alternate exposed second antenna 155 b is cleared to be able to produce its unique RF signature.", "Similarly, all antennae that wee written upon are cleared to produce their respective RFID signatures which are stored in a database together with their respective positions on the substrate sheet.", "Note that blocked third antenna 153 can not produce its unique RFID signature.", "Similarly, all antennae that were not written upon, are still not able to produce their respective RFID signature.", "FIG. 4 a depicting a plurality of transponders or tags in array each being RFID readable with a unique signature and comprising a respective antenna and a respective chip whereby a select subset of signatures has been altered by a user writing indicia whereby RFID detectibility, intensity, frequency, and/or modulation has been altered in the writing of the indicia.", "FIG. 4 b illustrates an RIFD sensed map of the letter of FIG. 4 a and the sensing process.", "Exposed antennae are able to produce their individual respective RF signatures including the first unblocked antenna 151 b , and the second unblocked antenna 155 b .", "Unexposed antennae still remain blocked from producing their RFID signatures including the third blocked antenna 153 .", "The processes of converting the altered antennae into meaningful data o control processes is the same as that described in FIG. 2 b .", "FIG. 4 b depicting a plurality of transponders or tags in array whereby some are RFID readable and have a signature corresponding to one stored in memory.", "FIG. 4 b further depicting a plurality of transponders or tags in array whereby RFID signatures have been altered by a user with respect to RFID detectibility, intensity, frequency, modulation pattern.", "FIG. 4 b also depicting an RFID process whereby a plurality of RFID signatures are sensed by an RFID reader, the signatures that are sensed are compared to those in memory and are mapped to specific relative predefined positions in memory to establish which areas of the substrate sheet have been altered and which have not been altered.", "A map of altered or unaltered signatures is then compared to indicia stored in memory such as is common with OCR software and processes.", "The read RFID altered signatures thereby being converted to hand written or typed data read using RFID processes and converted to data for storage in memory and use is processes.", "FIG. 5 a illustrate a sheet of arrayed RFID tags each having a unique signature with printed indicia and a selection made.", "An example of an application of the present invention is a routing ticket for a passenger or merchandise.", "The ticket can have words printed upon it such as a first destination and selection boxes such as non-selected box 167 and selected box 163 .", "The status of the ticket can be remotely sensed using RFID techniques known in the prior art.", "During the processing of the sensing and processing steps according to FIG. 2 a , the area on the ticket which is perforated will be sensed as an altered part of the map since the antennae in that area have been physically removed or destroyed.", "FIG. 5 b illustrates a side view of a small section of FIG. 1 a .", "The second antenna 123 may protrude above the surface of the substrate so as to be easily written upon such that indicia electrically communicates with it or it can easily be destroyed in the writing process as in FIG. 5 c. FIG. 5 c illustrates a side view of a small section of FIG. 1 b .", "The alternate first antenna 123 b has been physically broken by the writing process (as compared to FIG. 5 b ) which alters or destroys its RF signature from that possible in FIG. 5 b. FIG. 5 d illustrates a side view of a small section of FIG. 3 a .", "The RF signature blocking layer 181 covers the blocked antennae including second blocked antenna 155 .", "Between antennae may be a inert substrate 171 .", "FIG. 5 e illustrates a side view of a small section of FIG. 3 b .", "The second exposed antenna 155 a can produce an RFI signal that can be read after the extracted blocking layer 181 a has been removed in the writing step.", "FIG. 5 f illustrates a side view of a small section of FIG. 3 a in an alternate embodiment.", "In some applications, blocking the RFID signal may require use of an additional bottom RF blocking layer 173 to insulate the antennae from producing signatures.", "FIG. 5 g illustrates a side view of a small section of FIG. 1 b in an alternate embodiment.", "The compressed first antenna 123 c has been physically broken by the writing process (as compared to FIG. 5 b ) which alters or destroys its RF signature from that possible in FIG. 5 b .", "The physical shape was facilitated by an altered substrate 127 a which comprises a material that compresses when written upon such that antennae thereon are altered in the writing or printing processes.", "Second Embodiment Multiple RFID Signatures with Common Antenna Comprise One Tag or Transponder FIG. 6 a illustrates a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a detectible format.", "A first RFID chip 321 is one of a plurality of chips arrayed upon a first multi-chip substrate 329 .", "A second RFID chip 323 is one of the plurality of chips arrayed on the first multi-antennae substrate.", "When subjected to a predetermined electromagnetic field, the first RFID chip is engineered to emit a first signature characterized by a first combination of frequency, intensity, and modulation pattern.", "When subjected to a predetermined electromagnetic field, the second RFID chip is engineered to emit a second electromagnetic signature characterized by a second combination of frequency, intensity, and modulation pattern.", "The first signature and the second differ from one another.", "Both the first RFID chip and the second RFID chip are electronically in communication with a common antenna 325 according to processes well know and widely practiced in the art.", "The first RFID chip and the second RFID chip being engineered to correspond with a transceiver using a predetermined protocol and an example of a chip that could be used is the so called “mu-chip”", "from Hitachi, Ltd. The chips are affixed to the substrate in a manner such that when written or printed upon, their ability to emit their predetermined signature is altered.", "For example, a user may use a pencil to write on the substrate according to FIG. 6 b such that the signatures of chips being physically written upon are altered by the writing process.", "The first multi-chip substrate comprising a material that can accept written indicia from a printer, pencil, pen or other indicia producing mechanism.", "Both the first RFID chip and the second RFID chip are electrically in communication with a second half of a common antenna 325 according to processes well know and widely practiced in the art.", "While the embodiment of FIG. 6 a comprises chips which are connected to two sides of an antenna it should be understood that many other antenna configurations are possible.", "A plurality of antennae and associated RFID chips are also present on the first multi-chip substrate.", "As discussed in previous figures, the physical position of a plurality of signatures is known and stored in a memory for later plotting of an altered signature map according to the process of FIG. 2 b .", "Whereas in previous figures, the each RFID chip had its own antennae, in FIG. 6 a , each antenna has a plurality of chips in respective communication therewith FIG. 6 b illustrates the elements of FIG. 6 a with indicia printed thereon.", "A user has used a pencil to physically write a first multi-chip altering “R”", "character 331 .", "The physical writing process has caused a number of RFID chips to be removed from the first altered multi-chip substrate 329 a and thereby altering the removed chips'", "respective ability to produce their respective predefined signature.", "FIG. 6 c illustrates the signature map of the elements of FIG. 6 b when being sensed using RFID and plotted against a map in memory.", "Using the processes according to FIG. 2 b and FIG. 9 , a transceiver will sense all of the unaltered signatures on the FIG. 6 b substrate.", "These unaltered signatures will be mapped against a map of the original unaltered signatures of each RFID chip in array in FIG. 6 a .", "A computer processor will generate a map similar to that is 6 c comprising areas where no unaltered signatures were detected including the first signature from the first RFID chip 321 a of FIG. 6 a .", "The generated map will also comprise areas where altered signatures were detected or where no signatures were detected such as first RFID chip array area of altered signatures 335 .", "Note that the signature from the second RFID chip was not detected and is absent from the map since the chip's ability to emit its signature was altered in the writing process described in FIG. 7 b .", "The shape of 335 will be one determining factor that the character recognition processes according to FIG. 2 b and FIG. 9 utilize in changing the map into usable and search data to support subsequent processes.", "FIG. 7 a illustrates a top view of a plurality of RFID devices comprising unique signatures arrayed on a substrate in a non-detectible format.", "A first isolated RFID chip 341 is one of a plurality of chips arrayed upon a second multi-chip substrate 349 .", "A second isolated RFID chip 343 is one of the plurality of chips arrayed on the second multi-antennae substrate.", "When subjected to a predetermined electromagnetic field, the first isolated RFID chip is engineered to emit a first signature characterized by a first combination of frequency, intensity, and modulation pattern.", "When subjected to a predetermined electromagnetic field, the second isolated RFID chip is engineered to emit a second electromagnetic signature characterized by a second combination of frequency, intensity, and modulation pattern.", "The first signature and the second differ from one another.", "Neither the first isolated RFID chip nor the second isolated RFID chip are not electrically in communication with an isolated common antenna 345 thus they are not able to produce their respective detectible signatures until the are connected in an indicia production step according to FIG. 7 b .", "The first isolated RFID chip and the second isolated RFID chip being pre-engineered to correspond with a transceiver using a predetermined protocol and an example of a chip that could be used is the so called “mu-chip”", "from Hitachi, Ltd. The chips are affixed to the substrate in a manner such that when written or printed upon, the are connected to the isolated antenna thus their ability to emit their predetermined signature is altered (in this case altered from undetectable to detectible).", "For example, a user may use a pencil pen printer or other device to write on the substrate according to FIG. 7 b such that the altered chips that are written upon are electrically connected to the isolated antenna.", "The second multi-chip substrate comprising a material that can accept written indicia from a printer, pencil, pen or other indicia producing mechanism, the prior art including some references herein describing such.", "Returning to FIG. 7 a , both the first isolated RFID chip and the second isolated RFID chip are electronically isolated from a second half of a common isolated antenna 347 (until one is written upon as in FIG. 7 b ).", "While the embodiment of FIG. 7 a comprises chips which are connected to two sides of an antenna it should be understood that many other antenna configurations are possible.", "A plurality of antennae and associated RFID chips are also present on the second multi-chip substrate.", "Each of the chips on the second multi-chip substrate are electronically isolated from contact with any antennae in FIG. 7 a until some are selectively electrically connected as a result of the writing of indicia according to FIG. 7 b .", "As discussed in previous figures, the physical position of the entire plurality of RFID chip signatures is known and stored in a memory for later plotting of an altered signature map according to the processes of FIG. 4 b and FIG. 9 .", "Whereas in FIG. 6 a , each (and all) of the RFID chips were placed upon the first substrate in electrical communication with at least one respective antennae, in FIG. 7 a , each (and all) of the RFID chips are placed upon the second substrate in electrical isolation from any of the antennae.", "FIG. 7 b illustrates the elements of FIG. 7 a with indicia printed thereon.", "A user has used a printer to physically write a first multi-chip altering “D”", "character 331 .", "The physical writing process has caused a number of RFID chips to be electrically connected to an antenna on the second altered multi-chip substrate 349 a and thereby altering the electrically connected chips'", "respective ability to produce its predefined signature, such that those chips that have been printed upon can emit their signatures through printed antenna connections while those chips that have not been printed upon still are not able to transmit their signatures due to having no antenna connection.", "FIG. 7 c illustrates the signature map of the elements of FIG. 7 b when being sensed using RFID and plotted against a map in memory.", "Using the processes according to FIG. 4 b and FIG. 9 , a transceiver will sense all of the altered signatures on the FIG. 7 b substrate.", "These altered signatures will be mapped against a map of each RFID chip in array in FIG. 6 a .", "A computer processor will generate a map similar to that in 7 c comprising areas where no signatures were detected such as no mapped signatures area 353 which includes a blank section corresponding to the position of the first isolated RFID chip 341 of FIG. 7 a since this chip was not written upon, it remains electrically isolated from an antenna and its signature intensity is essentially zero.", "The generated map will also comprise areas where altered signatures were detected (that is to say the intensity of their respective signals have been altered from a zero state to a detectible non-zero state).", "Map representation of altered signatures include second isolated RFID chip signature 343 a which is among the signatures which have been altered to be detectible as a result of the indicia writing process in FIG. 7 b and its position in the map corresponds to the position of the second isolated RFID chip on the second substrate of FIG. 7 a .", "The shape of the detected chip area will be one determining factor that the character recognition processes according to FIG. 2 b and FIG. 9 utilize in translating the map into usable and searchable data to support subsequent processes.", "FIG. 8 a illustrates a side view of a RFID free form label with indicia printed thereon and stuck to the side of a parcel.", "A parcel 301 has been diverted from its distribution route by a worker in the distribution system due to water damage.", "The parcel has a unique identifier EPC tag 303 which identifies it as distinct.", "The worker has completed a supplemental RFID writable label 305 according to the art described in this invention.", "The worker hand writes the EPC code from the EPC label onto the supplemental RFID writable label in an EPC writable section 307 of the supplemental tag.", "Thus when the supplemental label is read subsequently, a character recognition program will identify the EPC code written thereon as part of the record associated with the original EPC tag and parcel.", "The worker also hand wrote the reason for diversion in the free form field section 301 of the supplemental tag as “Water Damaged.”", "A checked box 309 on the supplemental label represents a predefined area on the label where if any detectible alteration occurs, a predefined process step will be executed.", "In this illustration, the parcel will be shipped back to the manufacturer for refurbishing.", "All of the written characters in FIG. 8 a will be sensed and processed according to FIG. 9 to convert hand written indicia into usable data that is used in processes.", "The predefined area, namely the checked box doesn't require any character recognition step.", "Any signature alteration in the predefined area section of the writable tag (or memory alteration according to FIG. 11 ) will result in a predefined process step such as is detailed in an initiate altered signature process 243 of FIG. 9 .", "This is because the signature map that is stored in memory includes specific instructions that are invoked when specific altered signatures are sensed in the RFID sensing process.", "FIG. 8 b illustrates a top view of a RFID free form label with indicia printed thereon and stuck on an envelope.", "A paper envelope 313 has been labeled using an RFID readable free form field hand writable label 315 according to the present invention.", "The RFID readable free form field hand writable label includes a predefined zip code box 319 that is a special area defined in memory where a number sensed in the RFID altered signature sensing process is known to be part of a zip code.", "In the freeform field section, the address 317 is hand written.", "After the label is hand written or typed upon, it is completely covered by a thin plastic film (not shown) which is adhered to its surface to protect the label from further alteration.", "When this envelope is mailed, the processes of FIG. 9 will be used to turn the hand written indicia into meaningful alpha numeric character data for properly routing the envelope autonomously.", "The address label may have a unique identifier RIFD signature associated with it to distinguish it from other envelopes.", "FIG. 9 illustrates a process flow chart of sensing altered RFID signatures and for converting sensed signatures of written indicia into data.", "The flow chart of FIG. 9 and the discussion of it is applicable to many steps and processes described in the preceding diagrams and is also applicable to the processes of hand writable or printable memory and ensuing character recognition according to FIGS. 10 , 11 , and 12 and the discussion of them.", "FIG. 9 depicts processes and steps including the following discussion, some of which are required and others of which are optional.", "A produce RFID tag comprising a plurality of RFID signatures in array process 201 is first undertaken according to the preceding FIGS. 1 through 8 b .", "A comparable process relating to FIGS. 10 , 11 , and 12 would be the production of a physical memory substrate and then the integration of it with an RFID device such as a tag or transponder.", "In the manufacturing process a create predefined field in proximity to manufacture printed indicia step 203 may be undertaken.", "If undertaken, this step entails a printing of indicia on the tag during the manufacturing process and defining these areas in memory during a memory storage process 207 discussed later.", "Examples of predefined fields in proximity to manufacture printed indicia includes the predefined check box and hand writable EPC fields of FIG. 8 a and the predefined zip code fields of FIG. 8 b .", "The manufacture printed indicia is a visible queue to assist a worker in a subsequent step or process to place information on the tag in a predefined position (predefined in memory and a physical position on the substrate) as described such that information placed on the tag in relation to the manufacture printed indicia can be efficiently interpreted and be used in a process.", "The manufacturer printed indicia step can be applicable to all three embodiments herein.", "Whether the tag has manufacture printed indicia or not, it may come from the manufacture with detectible RFID signatures after a signatures enabled step 205 or it may come from the manufacturer with un-detectible signatures after a signatures not enabled manufacturing process 205 a .", "(In either case it may also have a readable unique identification signature that is distinct.) The former is described in FIGS. 1 a - 2 b , and 6 a - 6 c , and the later is described in FIGS. 3 a - 4 b and 7 a - 7 c .", "It should be noted that these figures and associated descriptions can be utilized with the third embodiment described herein which as described as coming from the manufacturer with memory connections not made but might also be manufactured with memory connections made and whereby during the user writing indicia process, memory connections are severed as the alteration step that will form the basis of comparison when performing the character recognition or predefined processes steps of FIG. 9 .", "An initial storage in memory process 207 prepares the memory for subsequent processes of FIG. 9 and throughout all three embodiments.", "The initial storage in memory process may contain multiple storage steps and storage of multiple types of information.", "A list of unique identifiers associated with each individual free form field writable tag may be stored in memory.", "A list of defined signatures may be stored in memory according to the first and second embodiment.", "A map of defined signature positions on the substrate may be stored in memory according to the first and second embodiment.", "A library of prospective indicia including characters and words may be stored in memory to support character recognition processes in the first, second and third embodiments for the purpose of converting RFID sensed patterns into meaningful data that can be used in subsequent processes via the converting of sensed patterns involving their comparison to the library of prospective indicia initially stored in memory.", "A list or map of predefined signatures for the first and second embodiments and of positions on respective substrates in all the three embodiments may be stored in memory where they represent fields associated with manufacture printed indicia.", "Predefined processes associated with the manufacture printed indicia may be stored in memory whereby alterations to predefined areas will invoke the predefined processes from memory.", "Examples of processes which are stored in memory in connection with a manufacture printed indicia are the predefined check box and hand writable EPC fields of FIG. 8 a and the predefined zip code fields of FIG. 8 b .", "Stored in memory in connection with the checked box is a process including instructions to return the parcel to the manufacturer if the box is checked.", "Whether the box is checked can be determined by RFID sensed data patterns including predefined signature alterations in the first two embodiments and a predefined memory readout pattern according to the third embodiment.", "Stored in memory in connection with the manufacturer printed hand writable EPC input fields is a process to consider alphanumeric characters hand written into this field to be part of a unique EPC code.", "In the first second and third embodiments Processes stored in memory may be in connection with characters that are recognized during a character recognition step or processes may be stored in memory in connection with their physical locations on the respective substrates.", "The zip code fields of FIG. 8 b being an example of the former and the checked box of FIG. 8 a being an example of the later.", "The process invoked by the former being routing of an envelope and the later being an example of a parcel routing process.", "It is note worthy that the memory contemplated in this initial storage in memory process is a remote memory connected to a network that contains data about the tagged item and typically tracks items through business processes but the memory that is loaded in this initial storage in memory process may also comprise memory storage on the tag itself which is accessible through RFID.", "Each of the three embodiments described herein comprise a step of alteration as the means to convey meaningful information.", "The first two embodiments involve the alteration of predefined RFID signatures with respect to any of detectibility, intensity, frequency, or modulation pattern.", "The third embodiment involving the alteration of memory locations (connections) from an “off”", "state to an “on”", "state or from an “on”", "state to an “off”", "state.", "Several means exist in the prior art for altering including hand processes 211 such as writing with a pencil or pen, machine processes 213 such as using a printer to print electrically conductive ink, and other processes 215 such as a paper punch severing a portion of the tag.", "In any case, alteration of the tag's composite RFID signature results from the alteration step.", "Additionally, the alteration step may involve user creation of alphanumeric text 217 , indicia 219 , a filter 221 , or detachment of a portion 223 of the tag.", "As discussed, the alteration process in the first two embodiments involve the alteration of predefined RFID signatures step 225 with respect to any of detectibility alteration step 229 , intensity alteration step 233 , frequency alteration step 227 , or modulation pattern alteration step 231 .", "The third embodiment involving the alteration of memory from an “off”", "state to an “on”", "state or from an “on”", "state to an “off”", "state the alteration being communicated via the modulation pattern alteration step 231 .", "Each of the three embodiments involve an RFID sensing process 235 .", "Using well known active or passive emitting processes, sensing processes, protocols, and querying and responding strategies altered information is transferred from the tag to a transceiver.", "In the first two embodiments, part of the RFID sensing process will involve sensing a first signature, sensing a second signature, and sensing all signatures until the final or Nth signature from a tag is sensed.", "In the third embodiment, part of the RFID sensing process may involve sensing a binary modulation pattern that is indicative of alterations to the writable and erasable physical indicia memory of FIGS. 10-12 b whereby bits that are written upon are 0's and areas that are not written upon are 1's.", "In the first two embodiments, a comparator process 237 is performed whereby the 1 st sensed signature is compared to signatures defined in memory to determine if sensed signatures match signatures in memory.", "In an iterative process the first sensed signature is compared to those in memory, the second sensed signature is compared to those in memory, and all sensed signatures are similarly compared to memory including the last or Nth sensed signature.", "A notation is made in memory of those signatures that are sensed and matched to ones in memory in a store sensed signatures in memory step 239 .", "In the third embodiment, the modulation of 1's and 0's from the tag representative of whether and where user alteration of the tag has occurred is stored in memory in the store sensed signatures in memory step 239 .", "The short path to transforming sensed information into business process invocation comprises two steps including a specific missing or altered signature step 241 where a specific area on a respective substrate has been altered and that altered area is associated with a specific predefined process in memory in which case an initiate altered signature process 243 is initiated.", "A special case of these two steps is the case including a detectible altered signature step 241 a where signatures in the original substrate were not detectible before being user altered such as is the case with FIGS. 3 a through 4 b and 7 a through 7 c .", "In this case an initiate detectible signatures process 243 a is commenced where a specific area on a respective substrate has been altered and that altered area is associated with a specific predefined process in memory.", "The longer path to invoking processes comprises the recognition of characters using altered signature as a proxy in the first two embodiments and using alter modulation patterns from memory connections as a proxy in the third embodiment.", "A plot sensed defined signatures against a map in memory process 245 is performed when user printed indicia is to be converted into readable data In the first and second embodiments, this involves plotting sensed signatures into a map of where their associated emitters are respectively positioned upon their respective substrate.", "The sensed signature map will comprise areas where signatures have been altered and areas where signatures have not been altered.", "Shapes of the altered areas can then be compared to the indicia or character library in memory in a subsequent character recognition step.", "In the third embodiment the plot sensed defined signatures against a map in memory process 245 is performed when user printed indicia is to be converted into readable data and it involves plotting sensed 1's and 0's into a map of where their associated memory contacts are respectively physically positioned upon their respective substrate.", "The resulting map of sensed memory contacts will comprise areas where memory contacts have been altered (where electrical contacts have been connected or disconnected) and areas where memory contacts have not been altered.", "Shapes of the altered areas can then be compared to the indicia, word, or character library in memory in a subsequent character recognition step.", "In any case, the resulting plotted map may be stored in a store sensed map in memory step 247 .", "In all three embodiments, where user alterations are to be converted to recognized characters or indicia, a compare plotted sensed signatures to recognized indicia, character, or word library in memory step 249 is under taken.", "This process is identical to well known optical character recognition (OCR) processes except that whereas OCR utilizes optical scanning to acquire an image map and the image map represents visual indicia on a substrate, the present invention uses a mechanism such as alteration of signatures or memory connections on a substrate as a proxy for an image and they are communicated through RFID to acquire an image map.", "The comparator process herein is otherwise the same as OCR.", "Thus in the present invention, a step where indicia is recognized 251 occurs.", "In a store sensed and recognized indicia in memory step 253 , indicia that was placed on the substrate by a user, transmitted through a proxy indicator using RFID, mapped, and compared to recognized indicia, has been recognized, and is then stored in memory as useable and searchable data.", "The data can then be the basis for business processes including key word searching of memory processes 259 , and an accessing recognized sensed indicia processes from memory step 255 .", "The recognized data can be used to initiate recognized sensed indicia processes 257 .", "Third Embodiment Physical Indicia Based Memory and RFID Facilitated Character Recognition FIG. 10 illustrates a simple circuit that can serve as a writable and erasable physical indicia based memory and sensor.", "A user writeable and erasable physical memory 401 comprises a number of open circuit connections comprising two sides of a circuit including a raised contact point 405 that is on a first side of the circuit including a column 403 .", "The raised contact point being one of a plurality of similar raised contact points which are arrayed to be electronically isolated from one another and from the second side of the circuit except when addressed by a flip-flop array including a first flip-flop 404 through an iterative process controlled by a pulse timer 402 .", "On the second side of the circuit is a raised contact line 407 which is one of a plurality of similar raised contact lines in array.", "The raised contact lines are electrically isolated from the raised contact points exception when connected by the writing of indicia according to FIG. 11 .", "The raised contact lines are in electrical communication with a serial shift register 411 which in operation in FIG. 11 produces a serial data stream 409 that describes which contacts (or memory locations) are connected by the writing of indicia and which are not connected.", "The shift register can also be seen in FIG. 12 b .", "In practice, the user writeable and erasable physical memory 401 is integrated with a substrate (not shown) such as a paper product that has an upper surface essentially equal to the height of the raised contact points and raised contact lines.", "The user writeable and erasable physical memory is integrated with a tag or transponder according to FIG. 12 a or 12 b to enable a tag that can receive written indicia comprising electrically conductive material that concurrently connects the raised contact points to raised contact lines.", "Prior to receiving written indicia, the user writeable and erasable physical memory is read as all 1's since no contacts between raised contact points and raised contact lines have been made.", "After a user writes indicia upon the substrate and thereby connects selected raised contact points to raised contact lines, the user writeable and erasable physical memory is read as a serial combination of 1's where no connection has been made and 0's where connections have been made and these 1's and 0's are a proxy indicator describing where indicia is written upon the substrate and they are transmitted through the FIG. 12 a or 12 b RFID architecture according to FIG. 9 and FIG. 11 and selectively subjected to processes described therein.", "The processes to alter select RFID signatures 209 of FIG. 9 and related discussion herein is applicable to the user writeable and erasable physical memory.", "The 1's and 0's transmitted being transmitted in sequence and the 0's representing altered memory connections.", "If the user writeable and erasable physical memory is written upon with a pencil or erasable ink, indicia written thereon can be erased as can the electrical connections the indicia made.", "The user writeable and erasable physical memory can be scaled to be nearly any size and resolution using well known principles and available electronic circuitry, the version described in FIG. 11 being significantly larger and having a higher resolution (number of raised contact points per inch).", "Also, while the user writeable and erasable physical memory version depicted in FIG. 10 begins with all contacts open, it could just as well begin with all contacts closed similarly to the discussion of FIGS. 7 a - 7 c whereby during the writing process, memory contacts are severed and that comprises the alteration step that will form the bases of comparison when performing the character recognition or predefined processes steps of FIG. 9 .", "FIG. 11 illustrates a process for communicating indicia stored in written form according to FIG. 10 and for sensing indicia and translating the indicia to data to be utilized in additional processes.", "A high resolution user writeable and erasable physical memory substrate 401 a has “DoD”", "indicia written thereon and is integrated with an indicia memory enhanced RFID transponder tag 413 according to FIG. 12 a or 12 b .", "When caused to do so by a transceiver, the indicia memory enhanced RFID transponder tag 413 produces a transmission 415 which comprises the 1's and 0's corresponding to contacts made by the “DoD”", "indicia written thereon and which is received by the high resolution user writeable and erasable physical memory substrate transceiver 417 .", "A map of received memory contacts 423 can be saved in a transceiver connected memory 427 .", "A processor 421 will perform a character recognition process 421 where the map of received memory contacts 423 is compared to a character library 429 .", "A contact connections mapped 435 is indicative of one connection on the high resolution user writeable and erasable physical memory substrate 401 a that has been made, transmitted, received, and mapped according to the order received through an altered modulation pattern comprising 1's and 0's presented in the order they are iteratively addressed by the integrated circuit according to FIG. 10 .", "Recognized characters 425 are stored in memory as data which can be subjected to a data search or business process step 431 .", "Integrated character recognition 433 can alternately be integrated directly with the high resolution user writeable and erasable physical memory substrate if desired.", "Also, An intermediary tag 430 comprising an intermediary memory 434 may also be utilized if desired.", "An intermediary tag might be useful where supplemental data is to be added to a primary tag such as was described in FIG. 8 a .", "In which case intermediary primary and secondary transmission 432 and intermediary primary and transceiver transmission 436 are utilized.", "FIG. 12 a illustrates an RFID transponder or tag formed by a simple circuit integrated with the indicia memory circuit according to FIG. 10 .", "An integrated writable and erasable physical indicia memory 401 b according to FIGS. 10 , and 11 , is integrated with a simple transponder circuit 413 a comprising a modulator 435 which is utilized to modulate the status of each respective raised contact point of FIG. 10 in a predetermined order so as to me mapped according to FIG. 11 as a proxy for indicia written upon a substrate which makes electrical contacts to physical memory positions according to FIGS. 10 and 11 .", "An EEPROM 437 may be in the circuit to communicate unique identifier information but this need not be the case.", "A separate power supply 439 may be provided depending upon the size, energy requirements, and other characteristics of the integrated writable and erasable physical indicia memory 401 b .", "In an alternate approach, an intermediary integrated transponder 401 b may transmit an intermediary integrated transponder signal 443 in lieu of a direct connection the simple integrated transponder circuit 413 a. FIG. 12 b illustrates an RFID transponder or tag formed by a circuit architecture common to Texas Instruments RFID devices integrated with the indicia memory circuit according to FIG. 10 .", "A Texas Instruments writable erasable physical indicia enhanced memory transponder 467 comprises the circuitry and processes to enable the art of FIGS. 10 , and 11 to work effectively as a transponder with writable erasable physical indicia enhanced memory.", "An end of burst 451 is sensed which causes an oscillator 453 to initiate a clock driver 455 to begin a modulation 463 according to a shift register 465 which facilitates the readout of data from a WEPIM 401 c (writable erasable physical indicia memory).", "A tuner 461 facilitates the oscillation with the transceiver (not shown).", "A discharge step 457 is provided to ensure the transponder is properly prepared for the next communication session with the transceiver.", "A voltage regulator 459 is in connection with a coil 467 which modulated to report the digital data from the WEPIM.", "An augmented power supply 439 may be provided if needed.", "Operation of the Invention Operation of the invention has been discussed under the above heading and is not repeated here to avoid redundancy.", "Conclusion, Ramifications, and Scope Thus the reader will see that the Configurable RFID Apparatus and Process of this invention provides a novel unanticipated, highly functional and reliable means for employing RFID techniques in a freeform RFID tag that comprises a plurality of smaller tags that can be used to capture as data a wide range of printed or written indicia which in turn can be used to drive an unlimited variety of processes.", "While the above description describes many specifications, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of a preferred embodiment thereof Many other variations are possible for example: The description herein illustrates the invention in a passive RFID tag, but it is understood to also be useful in active RFID tag systems.", "A few applications are described herein but it should be understood that the applications of the present invention are virtually limitless.", "Each RFID signature in the plurality of signatures arrayed on a substrate sheet can be truly unique.", "Alternately, the substrate sheet may have a single unique identifier signature with all of the other signatures being standard for the class of substrate sheets.", "The memory may store two signatures for each detectible devices whereby a user is able to alter a select combination of devices between their respective two sets of signatures such that each devices remains detectible in a predictable manner even after its signature has been altered.", "Audible or inaudible sound waves can be substituted for electromagnetic radiation energy as the medium to both excite a remote tag and to be sensed by the transponder and transceiver.", "Means of altering the readability of individual antenna signatures to achieve the ends of rendering an antenna to be either readable, unreadable, or readable with an altered signature have all been described herein using methods of communicating electrically with an antenna or circuits associated with an antenna, blocking or unblocking the ability of an antenna or circuits associated with an to produce an RF signal, or destrying the ability of an antenna or circuits associated with an to produce an RF signal.", "It is anticipated that other means are possible for achieving similar ends.", "Also, while the description herein focuses on interacting with the antenna as a means to produce an RF altered map, it is understood that any element such as a circuit which is in communication with an antenna can also be similarly altered to achieve identical ends." ]
BACKGROUND [0001] 1. Field of the Invention [0002] This invention relates to multicast, client/service-attribute resolution. More particularly the invention relates to discovering client applications and server applications having particular attributes and being located on multiple computing systems in an IP multicast group of computing systems. [0003] 2. Background of the Invention [0004] When there are multiple computers on a network, and there is no common system administrator with access to all of those computers, the computers must find devices on the network using some discovery process. Classically, a system administrator or a system network can monitor the network and say, for example, the network includes “Bob's Printer” which can be found at “IP address” and the printer supports “name” protocols. However in a wireless network, for example, each user has his own computing system, and there is no common system administrator in the network. The computer must discover “name” devices on the network for itself. [0005] There are currently extensions to the domain name service (DNS) which extensions are multicast domain name service (mDNS). One implementation is “Bonjour” service by Apple Computer Incorporated, which is used with the iTunes application program among others. Another implementation is Avahi service that is an mDNS service for Linux operating systems. The idea of these extensions to the domain name service is to allow computers to send out information about what services they support and to ask for information about what services other computers on the network support. [0006] In using mDNS there are two sides to a conversation: a requester and a responder. A requester asks other mDNS participants whether or not they support a particular service type, encoded as for example a “proto” protocol. A responder on each participant answers queries and would say, for example, I am named “Joe's phone” and I support the “proto” protocol. If more than one participant supports the “proto” protocol, multiple answers may be received by the requester. Typically the requester then decides which of the answers it is interested in and then performs a separate step to resolve the name “Joe's phone” and the protocol “proto” into an IP address and port over which the desired service can be reached. Attributes of the service may also be found during the resolve phase of the conversation and indicate for example characteristics of specific instance of the service. [0007] In peer-to-peer communications, where multiple users wish to interact as in playing a game, for example, mDNS can be used to link all the users into the same game. However, using mDNS to do this is very cumbersome. The computers desiring to participate in the game must all export the fact that they support the protocol used to establish the game and all devices must query for all other devices on the network that support the game establishment protocol. In order to contact each other, the separate step of resolving the returned names must be performed for every participant and any attributes of the individual participants must be resolved. There is a large amount of network and internal state overhead to track and keep consistent the “name” computers, computers that have the “game” protocols, and computers currently playing the game particularly as players enter and leave the game. To use mDNS to support such a game scenario, the network must either handle a large number of queries or it must store a large amount of network state information. [0008] It is with respect to these considerations and others that the present invention has been made. SUMMARY OF THE INVENTION [0009] In accordance with the present invention, proximity-based communications is established between client and service applications mediated by bus daemons. Client applications consume services and service applications provide services. A unique discovery protocol provides a name service in the bus daemon structure to assist the bus daemons in discovering the service applications available at other bus daemons. Bus daemons periodically announce their existence and provide the address and port over which they may be contacted. They also provide attribute information consisting of a description, such as an instance attribute and a well-known name attribute, of the service applications available at the bus daemon. The name service in the bus daemon structure may also respond to queries as to the availability of requested service applications. When client applications require access to a service application, they query their associated bus daemon that, in turn, queries its name service. When other bus daemons are discovered having access to a requested service application, the requesting client application may arrange that the bus daemons exchange information in a manner that allows a location independent connection to be made between the client application and service application. [0010] In accordance with other aspects, the present invention relates to an apparatus for discovering service applications available for communication through daemons in computing systems in a multicast group of computing systems. A daemon module in a computing system in the multicast group responds to discovery requests from its client applications and its service applications by initiating multicasts of attribute information for client applications and service applications. The attribute information for each client application and service application has at least a well-known-name attribute in the attribute information description of each application. A name service module in the computing system associated with the daemon module responds to a discovery request by initiating a discovery operation request. A responder module in the computing system associated with the name service module responds to the discovery operation request by sending a discovery message to the multicast group. The discovery message has attribute information with a given well-known-name of a service application making the discovery request at the computing system. Also, responder module responds to a first type discovery message from a computing system in the multicast group, the first type discovery message asking for any instance of a named service application with a well-known-name attribute matching one specified by a client application making a discovery request. If the computing system has such an instance of the named service application, the responder module sends a second type discovery message identifying the instance of the named service application with the well-known-name attribute at the computing system. Also, the responder module responds to a second type discovery message from a computing system in the multicast group. The second type discovery message announces an instance attribute and a well-known-name attribute for a service application at the computing system in the multicast group. The responder module notifies the daemon module of the availability of an instance of the service application with the well-known-name attribute at the computing system in the multicast group. [0011] In accordance with still other aspects, the present invention relates to a method for discovering service applications available for communication through a home bus daemon in the user's computing system or through the home bus daemon and a remote bus daemon in a remote computing system of a multicast group of computing systems. In response to a request from a service application available at the home bus daemon, an initiating operation initiates an advertise operation request from the home bus daemon. In response to an advertise operation request, an advertise message is multicast to the multicast group of computing systems. The advertise message has attribute information with an instance identifier and a well-known-name attribute of the service application at the user's computing system and an address of the home bus daemon through which the service application is available. In response to an advertise message from a remote bus daemon, the home bus daemon is notified of the availability of an instance of a service application with the well-known-name attribute at the remote bus daemon. [0012] In response to a discovery request from a client application at the user's computing system, an initiating operation initiates a find-name operation request from the home bus daemon. In response to a find-name operation request, a query message is multicast to the multicast group of computing systems from the home bus daemon, the query message asks for any service application having a well-known-name attribute that matches the name prefix attribute provided in the query message. In response to a query message, a detecting operation detects whether the home bus daemon has the service application that matches the well-known-name prefix attribute in the query message. The detecting operation sends an advertise message if an instance of the service application with the matching well-known-name attribute is available through the home bus daemon at the user's computing system. [0013] The invention may be implemented as a computer process, a computing system or as an article of manufacture such as a computer program product or computer readable media. The computer program product may be a computer storage media readable by a computer system and encoding a computer program of instructions for executing a computer process. The computer program product may also be a propagated signal on a carrier readable by a computing system and encoding a computer program of instructions for executing a computer process. [0014] Some advantages of the invention are the efficiency and speed with which client applications and service applications wishing to communicate with each other may discover each other. Another advantage of the invention is the ease with which client applications and service applications may enter or leave a group of applications that are communicating with each other. BRIEF DESCRIPTION OF THE DRAWINGS [0015] FIG. 1 shows a plurality of mobile computing systems communicating over a wireless network. [0016] FIG. 2 illustrates an exemplary computing system. [0017] FIG. 3 illustrates an architecture used by two computing systems to discover and link peer-to-peer client and server applications through bus daemons in each computing system. [0018] FIG. 4 illustrates a typical conversation between bus daemons such as those in FIG. 3 during the operation flow for discovering bus daemons having access to service applications. [0019] FIG. 5 shows the operation flow of a bus daemon and its name service acting in response to an ADVERTISE request from a service application. [0020] FIG. 6 shows the operation flow of a bus daemon and its name service acting in response to an FIND-NAME request from a client application. [0021] FIG. 7 illustrates the operation flow of a responder in a name service in response to operation requests. User Datagram Protocol packets, and timer events. [0022] FIG. 8 illustrates the operation flow of a bus daemon notifying interested client applications that a service application with a well-known-name attribute has been found. DESCRIPTION OF PREFERRED EMBODIMENTS [0023] FIG. 1 shows four computing systems—a laptop computer 102 , a tablet computer 104 , a smart phone 106 , and a desktop computer 108 —communicating over a wireless network using access point 110 . Laptop computer 102 or desktop computer 108 might be running the Windows (trademark of Microsoft Corporation) operating system or a Linux operating system. Each computing system wishing to participate in service discovery uses a name service to send UDP (User Datagram Protocol) messages to a predefined multicast group IP (internet protocol) address. [0024] To advertise the availability of a service application at a computing system, its bus daemon sends an advertise request to the name service. In response, the name service sends a UDP message to the multicast IP address. This UDP message includes a GUID (globally unique identifier) for the sending computing system's bus daemon, and the bus daemon's address (IPADDRESS,PORT). The UDP message also includes a list of names of service applications available through the bus daemon at the sending computing system including the newly advertised service application. In effect the sending bus daemon announces: [0025] a. “I have <org.example.Well-Known-Name.Instance> service application.” [0026] The “Well-Known-Name” attribute is typically the name of the program implemented by the service and client applications, but it may be an abbreviation, an acronym or any identifier for the program. The “Instance” attribute identifies an instance of the service application with the well-known-name attribute that is running on its computing system. Other instances of the service application with the well-known-name attribute at the same bus daemon or another bus daemon in the multicast group may be advertised at the same time. Each instance must have a unique identifier that might be established by the service application when it becomes active. Some possible examples of unique identifiers for an instance might be a unique number, a time stamp, user ID, player name or number, computer ID, bus daemon GUID, etc. [0027] For example, the user on a smart phone or laptop computer might want to play a multiplayer game with the well-known-name, SeaAdventure. The multiplayer game may be implemented as a service application to allow other instances of the game to communicate with the local instance of the game, but may also act as a client application to allow the local instance of the game to communicate with other remote instances. The local instance will have to advertise the existence of the local service application, but also discover remote instances of game's service application. This is done via two UDP messages sent by the name service to the multicast IP address. The first UDP message, an advertise message, would tell the bus daemon at every other computing system participating in the logical bus by listening at the multicast IP address that bus daemon GUID (global unique identifier) at IPADDRESS,PORT in the multicast group has available SeaAdventure.Player001, i.e. instance Player001 of SeaAdventure, game's service application. Of course the system could send multiple UDP messages, one per instance of a game, social media application, or other type of service application. Alternatively the system could send a list of instances of games, social media, or other type of service applications that the service application's sending bus daemon wishes to advertise. [0028] This advertise UDP message is referred to as an IS-AT message. In FIG. 1 if a UDP IS-AT message for SeaAdventureplayer001 game instance originates at laptop computer 102 , it is sent to the well-known IP multicast group. In the case of infrastructure mode IEEE 802.11 the packet is first sent to access point 110 and is then retransmitted to be received by laptop computer 102 , tablet computer 104 , smart phone 106 and desktop computer 108 . Each computer in this multicast group, if listening to the multicast IP address for the multicast group of the name service would know that a bus daemon at a known address has instance player001 of SeaAdventure game's service application. If a client exists on one of those computers that is interested in playing SeaAdventure game, it could connect to laptop computer 102 . This connect operation with laptop computer 102 creates the desired symmetrical arrangement of client and service applications. [0029] In another multi-player example, a user of laptop computer 102 enters a wireless network where other users of computing systems are already playing SeaAdventure game. The user will start a client application that will ask the bus daemon in the user's computer to locate instances of SeaAdventure game service applications. The bus daemon will ask the name service to discover those instances, and the name service will send out a UDP WHO-HAS message. This UDP WHO-HAS message is a query message asking: [0030] “Who has <org.example.SeaAdventure.*> service application?” [0031] The wild card asterisk(*) for the instance attribute indicates any instance of the service application with the well-known-name attribute, SeaAdventure, is being sought. The bus daemon of any computing system in the multicast group laptop computer 102 , tablet computer 104 , smart phone 106 and desktop computer 108 —that has an instance of the service application for SeaAdventure game, i.e. a user is currently playing the SeaAdventure game, would reply with an IS-AT message. The message contains the GUID (global unique identifier), IPADDRESS,PORT of the replying bus daemon and a string indicating that SeaAdventure game is available there. [0032] For example, if a user on smart phone 106 is playing SeaAdventure game, the name service on smart phone 106 replies with a UDP IS-AT message containing GUID and address of bus daemon of smart phone 106 and the message in effect saying, “I have Instance, Player001 of service application with well-known-name attribute SeaAdventure.” When the name service of laptop computer 102 receives the UDP IS-AT message, it indicates to its bus daemon that it has discovered a remote bus daemon that is advertising the fact that it has an active SeaAdventure game service application. The bus daemon, in turn, notifies its local client application. The client application can then decide to use the remote, advertised service application and ask the local bus daemon to connect to the remote bus daemon. This logical connection of bus daemons causes information to be exchanged between the bus daemons and that information enables remote procedure calls between the client and service applications. In the case where the SeaAdventure game application consists of both client and a service application part, the symmetric case allows bi-directional communication between the game instances. [0033] FIG. 2 is an exemplary computing system 200 representative of any type of computer, laptop computer, tablet computer, smart phone, desk top computer, or intelligent computing device that might be used to participate in a logical bus. Central processing unit (CPU) 202 is the main processing unit executing computer processes. CPU works with cache memory 204 in memory system 206 as well as program storage, file storage and working storage also contained in memory system 206 . Cache memory is usually directly linked to CPU 202 , while remaining storage in the memory system may be accessed through bus 208 . [0034] Keyboard module 210 is one input device available to CPU 202 through bus 208 . Another input device is a touch screen in display 211 . Display 212 with its touch screen serves as both an output device displaying information to a user and an input device receiving input from the user via the touch screen. Display 212 is connected to CPU 202 over bus 208 . [0035] Network control module 214 connects to CPU 202 to perform network control operations to connect the system to a wireless network via WIFI transceiver 216 or to a hardwired network through Ethernet adapter 218 . Network control module may be an intelligent module with its own computing system and memory including cache. Alternatively, it may be implemented as firmware or software running on CPU 202 . Likewise the keyboard 210 , display 212 memory system 206 may all be intelligent subsystems communicating over bus 208 . One skilled in the art is well aware of the many variations possible in the design of a computing system performing the logical operations of the various embodiments of the present invention. [0036] Computing system 200 , typically includes at least some form of computer-readable media. Computer readable media can be any available media that can be accessed by the computing system 200 . By way of example, and not limitation, computer-readable media might comprise computer storage media and communication media. [0037] Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD), magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or other optical storage devices, or any other medium that can be used to store the desired information and that can be accessed by the computing system 200 . [0038] Communication media typically embodies computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as an optical fiber network, a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared, and other wireless media. Combinations of any of the above should also be included within the scope of computer-readable media. Computer-readable media may also be referred to as computer program product. [0039] FIG. 3 illustrates two computing systems 302 and 304 in a logical bus consisting of two bus daemons with their associated client and service applications. The computing systems are in a multicast group such as the group shown in FIG. 1 . Client applications in the computing systems discover service applications during a discovery phase. After client applications have discovered service applications and asked the bus daemons to connect, they may pass remote procedure calls and replies between their clients and servers using TCP messages orchestrated by the bus daemons. Name service module 307 works with bus daemon 306 to send UDP advertisement messages from name service 307 in response to discovery requests by bus daemon 306 during the discovery phase. Likewise name service module 309 works with bus daemon 308 to send the UDP advertisement messages from name service 309 , in response to discovery requests by bus daemon 308 during the discovery phase. If, as a result of discovery messages, a client application on either computing system decides it wants to use a service application on the other computing system, it will ask the bus daemons to connect and exchange information. After the bus daemons have exchanged information and established peer-to-peer communications, the bus daemons are said to be joined. Now client applications in one computing system 302 or 304 may pass remote procedure calls to server applications in the other computing system, or vice versa. [0040] Each application program using a logical bus has a client application, a server application or a combination thereof to communicate with its local bus daemon and thereby communicate with other service applications in other computing systems. For example, a SeaAdventure game, application program in computing system 302 has a client application part 314 and service application part 312 , while another instance of the SeaAdventure game, application program in computing system 304 has client application part 322 and service application part 324 . Once the bus daemons 306 and 308 are joined, the sense of client or service application is unimportant. The client and service distinction is important only in the service discovery phase to indicate what system is requesting and what system is responding. Once the busses are joined, the client and service applications at computing system 302 or 304 can be viewed as a merged client/service application, or in this case a SeaAdventure game, application. Now if either client application 314 or service application 312 wishes to execute a remote procedure call at service application 324 or client application 322 , and if bus daemon 306 is joined with bus daemon 308 , bus daemon 306 will build a TCP message to pass the remote procedure call to bus daemon 308 . Bus daemon 308 in turn passes the procedure call to the desired client or service application 322 or 324 . Any return information is processed in an inverse fashion. Likewise if client application 322 or service application 324 in computing system 304 wishes to execute a remote procedure call at client application 314 or service application 312 in computing system 302 , bus daemon 308 will build a TCP message to pass the remote procedure call to bus daemon 306 . Bus daemon 306 in turn passes the procedure call to service application 312 or client application 314 . Return information is processed in an inverse fashion. [0041] If bus daemons 306 and 308 have not joined when the mobile computing systems come with wireless range of each other, and an instance of the SeaAdventure game, service application 312 is running at computing system 302 with the bus daemon 306 , the name service 307 periodically advertises the availability of the instance of SeaAdventure game, service application by multicasting a UDP Advertise message effectively announcing, “I have an instance of a service application with well-known-name attribute, SeaAdventure.” The UDP message with the GUID, IP ADDRESS, PORT for bus daemon 306 along with the well-known-name attribute and instance attribute of the service application 312 is multicast to all bus daemons of the computing systems within range of access point 310 at a local wireless network in a coffee shop, for example. The UDP message from name service 307 is received by all name services within range of the access point 310 that are monitoring the multicast address. Particularly, name service module 309 now knows that service application 312 for SeaAdventure game is available through bus daemon 306 in computing system 302 . [0042] Likewise, if a an instance of SeaAdventure game, service application 324 is running at computing system 304 with the bus daemon 308 , the name service 309 periodically advertises the availability of SeaAdventure game, service application by multicasting a UDP message effectively saying, “I have an instance of a service application with well-known-name attribute, SeaAdventure.” The UDP message with the GUID, IP ADDRESS, PORT for bus daemon 308 along with the well-known-name attribute and instance attribute of the service application 324 is multicast to all bus daemons of the mobile computing systems within range of access point 310 . The UDP message from name service 309 is received by all name services within range of the access point 310 that are monitoring the multicast IP address. Name service module 307 now knows that service application 324 for SeaAdventure game is available through bus daemon 308 in computing system 304 . Either client application ( 314 or 322 ) may ask their respective bus daemons to connect to the other in which case the bus daemons are joined into a logical bus. [0043] The client and server application nomenclature is symmetrical. Both client and server application parts of an application such as SeaAdventure game in this example are part of the same program running on different computing systems. Once the discovery phase is complete, and the bus daemons are joined, the client and server applications in a steady-state phase of operation are linked to each other and their remote procedure calls and replies flow through the bus daemons between the separate computing systems. [0044] FIG. 4 illustrates a typical conversation between bus daemons such as those in FIG. 3 during the operation flow for discovering bus daemons having access to service applications with a well-known-name attribute. This discovery conversation is initiated by a service application 402 sending an ADVERTISE request 404 to bus daemon 406 requesting the bus daemon to advertise the availability of a Well-Known-Name service application. This happens when an instance of the Well-Known-Name service application has just attached itself to the bus daemon. Bus daemon 406 with its name service module builds the UDP IS-AT message and multicasts message instance 408 of the IS-AT message to the multicast group. The UDP message includes a KEEP ALIVE timer count. Bus daemon 406 also decrements the timer count to establish KEEP ALIVE interval. Whenever the KEEP ALIVE interval is decremented to a configurable value, the name service at bus daemon 406 will re-advertise the service application by generating new IS-AT messages, for example message instances 414 , 426 and 427 . This periodic re-advertisement happens as long as service application 402 is attached to the bus daemon 406 and allows bus daemons that have missed prior advertisements to receive them, or bus daemons newly arrived on a network segment to likewise receive them. If the service application 402 closes, the KEEP ALIVE timer count is set to zero, and bus daemon 406 no longer multicasts IS-AT message for service application 402 . Accordingly, service application 402 can enter or leave participation in the Well-Known-Name application. [0045] In FIG. 4 , bus daemon 416 arrives in the local proximity and has a client application 418 that is interested in connecting to an instance of a service application with a well-known-name attribute. Client application 418 asks its bus daemon 416 to discover any instances of service applications having the Well-Known-Name. Name service module of the bus daemon 416 sends instance 420 of a WHO-HAS message. If service application 402 is active and has the Well-Known-Name attribute, name service module of bus daemon 406 constructs an IS-AT message indicating that an instance of a service application with the Well-Known-Name attribute is at bus daemon 406 . The name service of bus daemon 406 sends a packet of instance 422 of the IS-AT message to the multicast group IP address. [0046] Bus daemon 416 receives the IS-AT message from the name service component of bus daemon 406 . The Well-Known-Name is entered in the cache of names and bus daemon addresses at bus daemon 416 . The availability of service application 402 is communicated to client application 418 via FOUND-NAME message instance 424 . The discovery phase is completed. If client application 418 chooses to ask the daemons to connect, service application 402 and client application 418 will be able to send remote procedure calls and procedure results using TCP messages. Bus daemon 406 will continue to periodically multicast IS-AT messages according to the KEEP ALIVE interval with renewed timer counts to advise other bus daemons of the instance of the Well-Known-Name service application 402 . The TCP communication between bus daemons may be ended by one of the bus daemons sending a FIN message under control of either the client or service application. If service application 402 should close, this fact is advertised by sending an IS-AT message with a zero timer count. In this way, client applications and service applications may enter or leave participation in a well-known-name program at will without disrupting the operation of the program. [0047] The exemplary conversation between computing systems in a multicast group, as depicted in FIG. 4 and described immediately above, is performed by bus daemons and their name service modules working together to execute the operation flows shown in FIGS. 5-8 . A bus daemon in its computing system, when prompted by a request from a service application in FIG. 5 or client application in FIG. 6 , acts to initiate a multicast operation from a responder in the daemon's name service module. FIG. 7 illustrates the operation flow of the responder. FIG. 8 illustrates the operation flow of a daemon in the computing system notifying its client application that a service application has been found. [0048] The logical operations in the operation flow diagrams of the various embodiments of the present invention are implemented (1) as a sequence of computer implemented acts or program modules running on a computing system and/or (2) as interconnected machine logic circuits or circuit modules within the computing system. The implementation is a matter of choice dependent on the performance requirements of the computing system implementing the invention. Accordingly, the logical operations making up the embodiments of the present invention described herein are referred to variously as operations, structural devices, acts or modules. It will be recognized by one skilled in the art that these operations, structural devices, acts and modules may be implemented in software, in firmware, in special purpose digital logic, and any combination thereof without deviating from the spirit and scope of the present invention as recited within the claims attached hereto. [0049] In FIG. 5 , advertise operation 502 at the bus daemon receives from a service application a request to advertise attribute information about the service application. The advertise request corresponds to discovery request 404 ( FIG. 4 ). Advertise operation 502 saves the service application well-known-name, being advertised, in the application name cache 504 and calls the name service module 506 of the bus daemon. Name service module 506 saves the advertised well-known-name in the name service cache 508 and initiates a discovery operation request, which in this case is an ADVERTISE operation request, at multicast request operation 510 . Multicast request operation 510 sends the ADVERTISE operation request to a responder module in the name service module. The responder will multicast a discovery message containing the well-known-name attribute of the service application being advertised. [0050] In FIG. 6 , FIND-NAME operation 602 at the bus daemon receives from a client application a FIND-NAME message 419 ( FIG. 4 ) requesting the bus daemon to find a service application with a given well-known-name attribute. In one embodiment the given well-known-name attribute is the well-known-name prefix of the peer application making the discovery request. FIND-NAME operation 602 saves the client application well-known-name in the daemon's interested-client-applications name list 604 and calls the name service module 606 of the bus daemon. Name service module 606 initiates a discovery operation request, which in this case is a FIND-NAME operation request, at multicast request operation 608 . Multicast request operation 608 sends a FIND-NAME operation request to a responder module in the name service. The responder will multicast a discovery message containing the well-known-name prefix attribute of the service application being sought by the client application. [0051] FIG. 7 shows the operational flow of the responder module in the name service. The responder, like the bus daemon and name service, may come up when the computing system powers on and may stay up until the computing system powers off. Multiple responders are allowed on any given computing system. The operational flow begins at wait operation 702 . Wait operation 702 is waiting for receipt of a timer event, an operation request event or a UDP packet event. Event-type test operation 704 detects the type of event received by the wait operation 702 . If the event is an operation request event, the operation flow branches from event-type test operation 704 to operation-type detect module 706 . If the event is a UDP packet event, the operation flow branches to message-type detect module 708 . If the event is a timer event, the operation flow branches to the timer-expired detect module 710 . [0052] When the event is an operation request event, operation-type detect module 706 tests whether the operation request is a FIND-NAME operation request or an ADVERTISE operation request. If it is an ADVERTISE operation request, the operation flow branches from the operation-type detect module 706 to the IS-AT operation 712 . IS-AT operation 712 formats and sends a discovery message, in this case an IS-AT message, e.g. message 408 ( FIG. 4 ), effectively saying for its associated bus daemon, “I have <org.example.Well-Known-Name.Instance> service application.” From IS-AT operation 712 , the operation flow returns to wait operation 702 . [0053] If the operation request is a FIND-NAME operation request, the operation flow branches from the operation-type detect module 706 to the WHO-HAS operation 714 . WHO-HAS operation 714 formats and sends a discovery message, in this case a WHO-HAS message, e.g. message instance 420 ( FIG. 4 ), effectively asking for a bus daemon, “Who has <org.example.Well-Known-Name.*> service application? Then the operation flow returns to wait operation 702 . [0054] When the event is receipt of a UDP Packet from a remote bus daemon, message-type detect module 708 tests whether the UDP packet is an IS-AT message or a WHO-HAS message. If the UDP packet is an IS-AT message, the operation flow branches from the message-type detect module 708 to notify-daemon operation 716 . Notify operation 716 notifies the bus daemon associated. with responder that an IS-AT message for <org.example.Well-Known-Name.Instance> service application has been received, and the service application is available through a bus daemon at IPADDRESS,PORT in a remote computing system. [0055] The IS-AT UDP packet is generated at a remote computing system as a result of either an ADVERTISE operation request at a remote bus daemon or as a result of WHO-HAS UDP packet being received at the name service of the remote bus daemon. In either case the receipt of an IS-AT message by a name service at a home bus daemon in the user's computing system is handled by the responder's notify-daemon operation 716 . Notify operation 716 notifies the home bus daemon an instance of a service application with a well-known-name attribute is available for interested client applications (if any) attached to the home bus daemon. The operational flow of the bus daemon in response to the notification is shown in FIG. 8 described hereinafter. After the notify-daemon operation 716 in FIG. 7 , the operational flow returns to wait operation 702 . [0056] If the UDP packet from a remote bus daemon is a WHO-HAS message the operational flow branches from message-type detect module 708 to “have-name” test operation 718 . If the bus daemon does not have an instance of a service application with a well-known-name attribute as asked for in the WHO-HAS message, the operation flow branches NO from the have-name test operation 718 and returns to wait operation 702 to wait for the next event. If the bus daemon has an instance of a service application with the well-known-name attribute sought by the WHO-HAS message, the operation flow branches YES to IS-AT operation 712 . IS-AT operation 712 formats and sends an IS-AT message saying the home bus daemon has an instance of the well-known-named service application. IS-AT message instance 422 ( FIG. 4 ) is an example of an IS-AT message being returned in response to a WHO-HAS message. Note that IS-AT operation 712 will send an IS-AT message in response to an ADVERTISE operation request or an appropriate WHO-HAS packet event where the have-name test 718 is satisfied. After the IS-AT message is sent, the operation flow returns to wait operation 702 . [0057] When the event is a timer event, timer-expired detect module 710 detects whether the expired timer event was a retry timer or a keep-alive timer. If the timer event is a keep-alive timer event, the operation flow branches from timer-expired detect module 710 to keep-alive operation 720 . Keep-alive operation formats and sends an IS-AT message, e.g. message instances 414 , 426 and 427 , for all advertised names of service applications currently being advertised by a name service for a bus daemon. Even if a bus daemon sending the IS-AT message has joined with another bus daemon as a result of an earlier discovery process, the keep-alive operation will continue to provide an opportunity for other bus daemons in the IP multicast group to join with the bus daemon. From keep-alive operation 720 the operation flow returns to wait operation 702 . [0058] If the timer event is a retry timer event, the operation flow branches from timer-expired detect module 710 to retry operation 722 . Retry operation 722 resends a WHO-HAS message, e.g. messages instances 428 and 429 , seeking an instance of a well-known-named service applications currently being sought by a name service for a bus daemon with a client application seeking the named service applications. Even if the bus daemon retrying the WHO-HAS message has joined, with another bus daemon as a result of an earlier discovery process, the retry operation will continue to provide an opportunity for other bus daemons in the multicast group to join with the bus daemon by retrying the WHO-HAS message. From retry operation 722 . the operation flow returns to wait operation 702 . [0059] FIG. 8 illustrates the operation flow of a bus daemon in the computing system notifying its client application that an instance of a service application with a requested well-known-name attribute has been found. Notification operation 802 at the daemon receives notification from notify-daemon operation 716 in the responder of daemon's name service that the service application with the well-known-name attribute the same as the well-known-name prefix in a FIND-NAME request is available. The same-name operation 802 saves the service application's well-known-name in a found-name list in the daemon's found-name cache 804 . Notification operation 802 also saves the IPADDRESS,PORT of the bus daemon where the desired service application is located. Found-name operation 806 sends a FOUND-NAME message, e.g. message instance 424 ( FIG. 4 ), from the daemon to signal interested client applications of a found-name. The FOUND-NAME message includes the name of same named service application that has been found and the IPADDRESS,PORT of its bus daemon. This completes the discovery phase for the client application that initiated the FIND-NAME request. [0060] Although the invention has been described in language specific to computer structural features, methodological acts and computer processes on computer readable media, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific structures, acts or media described. As an example, other logical operations may be included in the bus daemon discovery process. Also to the extent FIGS. 3 and 4 have been described as conversations between two computing systems, such conversations will typically be occurring in parallel amongst multiple computing systems in an IP multicast group. Therefore, the specific structural features, acts and media are disclosed as exemplary embodiments implementing the claimed invention. [0061] The various embodiments described above are provided by way of illustration only and should not be construed to limit the invention. Those skilled in the art will readily recognize various modifications and changes that may be made to the present invention without following the example embodiments and applications illustrated and described herein, and without departing from the spirit and scope of the present invention, which is set forth in the following claims.
Proximity-based communications is established between client and service applications mediated by bus daemons. Client applications consume services and service applications provide services. A unique discovery protocol provides a name service in the bus daemon structure to assist the bus daemons in discovering the service applications available at other bus daemons. Bus daemons periodically announce their existence and provide the address and port over which they may be contacted. They also provide attribute information consisting of a description, such as an instance attribute and a well-known name attribute, of the service applications available at the bus daemon. The name service in the bus daemon structure may also respond to queries as to the availability of requested service applications. When client applications require access to a service application, they query their associated bus daemon that, in turn, queries its name service.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "BACKGROUND [0001] 1.", "Field of the Invention [0002] This invention relates to multicast, client/service-attribute resolution.", "More particularly the invention relates to discovering client applications and server applications having particular attributes and being located on multiple computing systems in an IP multicast group of computing systems.", "[0003] 2.", "Background of the Invention [0004] When there are multiple computers on a network, and there is no common system administrator with access to all of those computers, the computers must find devices on the network using some discovery process.", "Classically, a system administrator or a system network can monitor the network and say, for example, the network includes “Bob's Printer”", "which can be found at “IP address”", "and the printer supports “name”", "protocols.", "However in a wireless network, for example, each user has his own computing system, and there is no common system administrator in the network.", "The computer must discover “name”", "devices on the network for itself.", "[0005] There are currently extensions to the domain name service (DNS) which extensions are multicast domain name service (mDNS).", "One implementation is “Bonjour”", "service by Apple Computer Incorporated, which is used with the iTunes application program among others.", "Another implementation is Avahi service that is an mDNS service for Linux operating systems.", "The idea of these extensions to the domain name service is to allow computers to send out information about what services they support and to ask for information about what services other computers on the network support.", "[0006] In using mDNS there are two sides to a conversation: a requester and a responder.", "A requester asks other mDNS participants whether or not they support a particular service type, encoded as for example a “proto”", "protocol.", "A responder on each participant answers queries and would say, for example, I am named “Joe's phone”", "and I support the “proto”", "protocol.", "If more than one participant supports the “proto”", "protocol, multiple answers may be received by the requester.", "Typically the requester then decides which of the answers it is interested in and then performs a separate step to resolve the name “Joe's phone”", "and the protocol “proto”", "into an IP address and port over which the desired service can be reached.", "Attributes of the service may also be found during the resolve phase of the conversation and indicate for example characteristics of specific instance of the service.", "[0007] In peer-to-peer communications, where multiple users wish to interact as in playing a game, for example, mDNS can be used to link all the users into the same game.", "However, using mDNS to do this is very cumbersome.", "The computers desiring to participate in the game must all export the fact that they support the protocol used to establish the game and all devices must query for all other devices on the network that support the game establishment protocol.", "In order to contact each other, the separate step of resolving the returned names must be performed for every participant and any attributes of the individual participants must be resolved.", "There is a large amount of network and internal state overhead to track and keep consistent the “name”", "computers, computers that have the “game”", "protocols, and computers currently playing the game particularly as players enter and leave the game.", "To use mDNS to support such a game scenario, the network must either handle a large number of queries or it must store a large amount of network state information.", "[0008] It is with respect to these considerations and others that the present invention has been made.", "SUMMARY OF THE INVENTION [0009] In accordance with the present invention, proximity-based communications is established between client and service applications mediated by bus daemons.", "Client applications consume services and service applications provide services.", "A unique discovery protocol provides a name service in the bus daemon structure to assist the bus daemons in discovering the service applications available at other bus daemons.", "Bus daemons periodically announce their existence and provide the address and port over which they may be contacted.", "They also provide attribute information consisting of a description, such as an instance attribute and a well-known name attribute, of the service applications available at the bus daemon.", "The name service in the bus daemon structure may also respond to queries as to the availability of requested service applications.", "When client applications require access to a service application, they query their associated bus daemon that, in turn, queries its name service.", "When other bus daemons are discovered having access to a requested service application, the requesting client application may arrange that the bus daemons exchange information in a manner that allows a location independent connection to be made between the client application and service application.", "[0010] In accordance with other aspects, the present invention relates to an apparatus for discovering service applications available for communication through daemons in computing systems in a multicast group of computing systems.", "A daemon module in a computing system in the multicast group responds to discovery requests from its client applications and its service applications by initiating multicasts of attribute information for client applications and service applications.", "The attribute information for each client application and service application has at least a well-known-name attribute in the attribute information description of each application.", "A name service module in the computing system associated with the daemon module responds to a discovery request by initiating a discovery operation request.", "A responder module in the computing system associated with the name service module responds to the discovery operation request by sending a discovery message to the multicast group.", "The discovery message has attribute information with a given well-known-name of a service application making the discovery request at the computing system.", "Also, responder module responds to a first type discovery message from a computing system in the multicast group, the first type discovery message asking for any instance of a named service application with a well-known-name attribute matching one specified by a client application making a discovery request.", "If the computing system has such an instance of the named service application, the responder module sends a second type discovery message identifying the instance of the named service application with the well-known-name attribute at the computing system.", "Also, the responder module responds to a second type discovery message from a computing system in the multicast group.", "The second type discovery message announces an instance attribute and a well-known-name attribute for a service application at the computing system in the multicast group.", "The responder module notifies the daemon module of the availability of an instance of the service application with the well-known-name attribute at the computing system in the multicast group.", "[0011] In accordance with still other aspects, the present invention relates to a method for discovering service applications available for communication through a home bus daemon in the user's computing system or through the home bus daemon and a remote bus daemon in a remote computing system of a multicast group of computing systems.", "In response to a request from a service application available at the home bus daemon, an initiating operation initiates an advertise operation request from the home bus daemon.", "In response to an advertise operation request, an advertise message is multicast to the multicast group of computing systems.", "The advertise message has attribute information with an instance identifier and a well-known-name attribute of the service application at the user's computing system and an address of the home bus daemon through which the service application is available.", "In response to an advertise message from a remote bus daemon, the home bus daemon is notified of the availability of an instance of a service application with the well-known-name attribute at the remote bus daemon.", "[0012] In response to a discovery request from a client application at the user's computing system, an initiating operation initiates a find-name operation request from the home bus daemon.", "In response to a find-name operation request, a query message is multicast to the multicast group of computing systems from the home bus daemon, the query message asks for any service application having a well-known-name attribute that matches the name prefix attribute provided in the query message.", "In response to a query message, a detecting operation detects whether the home bus daemon has the service application that matches the well-known-name prefix attribute in the query message.", "The detecting operation sends an advertise message if an instance of the service application with the matching well-known-name attribute is available through the home bus daemon at the user's computing system.", "[0013] The invention may be implemented as a computer process, a computing system or as an article of manufacture such as a computer program product or computer readable media.", "The computer program product may be a computer storage media readable by a computer system and encoding a computer program of instructions for executing a computer process.", "The computer program product may also be a propagated signal on a carrier readable by a computing system and encoding a computer program of instructions for executing a computer process.", "[0014] Some advantages of the invention are the efficiency and speed with which client applications and service applications wishing to communicate with each other may discover each other.", "Another advantage of the invention is the ease with which client applications and service applications may enter or leave a group of applications that are communicating with each other.", "BRIEF DESCRIPTION OF THE DRAWINGS [0015] FIG. 1 shows a plurality of mobile computing systems communicating over a wireless network.", "[0016] FIG. 2 illustrates an exemplary computing system.", "[0017] FIG. 3 illustrates an architecture used by two computing systems to discover and link peer-to-peer client and server applications through bus daemons in each computing system.", "[0018] FIG. 4 illustrates a typical conversation between bus daemons such as those in FIG. 3 during the operation flow for discovering bus daemons having access to service applications.", "[0019] FIG. 5 shows the operation flow of a bus daemon and its name service acting in response to an ADVERTISE request from a service application.", "[0020] FIG. 6 shows the operation flow of a bus daemon and its name service acting in response to an FIND-NAME request from a client application.", "[0021] FIG. 7 illustrates the operation flow of a responder in a name service in response to operation requests.", "User Datagram Protocol packets, and timer events.", "[0022] FIG. 8 illustrates the operation flow of a bus daemon notifying interested client applications that a service application with a well-known-name attribute has been found.", "DESCRIPTION OF PREFERRED EMBODIMENTS [0023] FIG. 1 shows four computing systems—a laptop computer 102 , a tablet computer 104 , a smart phone 106 , and a desktop computer 108 —communicating over a wireless network using access point 110 .", "Laptop computer 102 or desktop computer 108 might be running the Windows (trademark of Microsoft Corporation) operating system or a Linux operating system.", "Each computing system wishing to participate in service discovery uses a name service to send UDP (User Datagram Protocol) messages to a predefined multicast group IP (internet protocol) address.", "[0024] To advertise the availability of a service application at a computing system, its bus daemon sends an advertise request to the name service.", "In response, the name service sends a UDP message to the multicast IP address.", "This UDP message includes a GUID (globally unique identifier) for the sending computing system's bus daemon, and the bus daemon's address (IPADDRESS,PORT).", "The UDP message also includes a list of names of service applications available through the bus daemon at the sending computing system including the newly advertised service application.", "In effect the sending bus daemon announces: [0025] a. “I have <org.example.Well-Known-Name.Instance>", "service application.”", "[0026] The “Well-Known-Name”", "attribute is typically the name of the program implemented by the service and client applications, but it may be an abbreviation, an acronym or any identifier for the program.", "The “Instance”", "attribute identifies an instance of the service application with the well-known-name attribute that is running on its computing system.", "Other instances of the service application with the well-known-name attribute at the same bus daemon or another bus daemon in the multicast group may be advertised at the same time.", "Each instance must have a unique identifier that might be established by the service application when it becomes active.", "Some possible examples of unique identifiers for an instance might be a unique number, a time stamp, user ID, player name or number, computer ID, bus daemon GUID, etc.", "[0027] For example, the user on a smart phone or laptop computer might want to play a multiplayer game with the well-known-name, SeaAdventure.", "The multiplayer game may be implemented as a service application to allow other instances of the game to communicate with the local instance of the game, but may also act as a client application to allow the local instance of the game to communicate with other remote instances.", "The local instance will have to advertise the existence of the local service application, but also discover remote instances of game's service application.", "This is done via two UDP messages sent by the name service to the multicast IP address.", "The first UDP message, an advertise message, would tell the bus daemon at every other computing system participating in the logical bus by listening at the multicast IP address that bus daemon GUID (global unique identifier) at IPADDRESS,PORT in the multicast group has available SeaAdventure.", "Player001, i.e. instance Player001 of SeaAdventure, game's service application.", "Of course the system could send multiple UDP messages, one per instance of a game, social media application, or other type of service application.", "Alternatively the system could send a list of instances of games, social media, or other type of service applications that the service application's sending bus daemon wishes to advertise.", "[0028] This advertise UDP message is referred to as an IS-AT message.", "In FIG. 1 if a UDP IS-AT message for SeaAdventureplayer001 game instance originates at laptop computer 102 , it is sent to the well-known IP multicast group.", "In the case of infrastructure mode IEEE 802.11 the packet is first sent to access point 110 and is then retransmitted to be received by laptop computer 102 , tablet computer 104 , smart phone 106 and desktop computer 108 .", "Each computer in this multicast group, if listening to the multicast IP address for the multicast group of the name service would know that a bus daemon at a known address has instance player001 of SeaAdventure game's service application.", "If a client exists on one of those computers that is interested in playing SeaAdventure game, it could connect to laptop computer 102 .", "This connect operation with laptop computer 102 creates the desired symmetrical arrangement of client and service applications.", "[0029] In another multi-player example, a user of laptop computer 102 enters a wireless network where other users of computing systems are already playing SeaAdventure game.", "The user will start a client application that will ask the bus daemon in the user's computer to locate instances of SeaAdventure game service applications.", "The bus daemon will ask the name service to discover those instances, and the name service will send out a UDP WHO-HAS message.", "This UDP WHO-HAS message is a query message asking: [0030] “Who has <org.example.SeaAdventure.*>", "service application?”", "[0031] The wild card asterisk(*) for the instance attribute indicates any instance of the service application with the well-known-name attribute, SeaAdventure, is being sought.", "The bus daemon of any computing system in the multicast group laptop computer 102 , tablet computer 104 , smart phone 106 and desktop computer 108 —that has an instance of the service application for SeaAdventure game, i.e. a user is currently playing the SeaAdventure game, would reply with an IS-AT message.", "The message contains the GUID (global unique identifier), IPADDRESS,PORT of the replying bus daemon and a string indicating that SeaAdventure game is available there.", "[0032] For example, if a user on smart phone 106 is playing SeaAdventure game, the name service on smart phone 106 replies with a UDP IS-AT message containing GUID and address of bus daemon of smart phone 106 and the message in effect saying, “I have Instance, Player001 of service application with well-known-name attribute SeaAdventure.”", "When the name service of laptop computer 102 receives the UDP IS-AT message, it indicates to its bus daemon that it has discovered a remote bus daemon that is advertising the fact that it has an active SeaAdventure game service application.", "The bus daemon, in turn, notifies its local client application.", "The client application can then decide to use the remote, advertised service application and ask the local bus daemon to connect to the remote bus daemon.", "This logical connection of bus daemons causes information to be exchanged between the bus daemons and that information enables remote procedure calls between the client and service applications.", "In the case where the SeaAdventure game application consists of both client and a service application part, the symmetric case allows bi-directional communication between the game instances.", "[0033] FIG. 2 is an exemplary computing system 200 representative of any type of computer, laptop computer, tablet computer, smart phone, desk top computer, or intelligent computing device that might be used to participate in a logical bus.", "Central processing unit (CPU) 202 is the main processing unit executing computer processes.", "CPU works with cache memory 204 in memory system 206 as well as program storage, file storage and working storage also contained in memory system 206 .", "Cache memory is usually directly linked to CPU 202 , while remaining storage in the memory system may be accessed through bus 208 .", "[0034] Keyboard module 210 is one input device available to CPU 202 through bus 208 .", "Another input device is a touch screen in display 211 .", "Display 212 with its touch screen serves as both an output device displaying information to a user and an input device receiving input from the user via the touch screen.", "Display 212 is connected to CPU 202 over bus 208 .", "[0035] Network control module 214 connects to CPU 202 to perform network control operations to connect the system to a wireless network via WIFI transceiver 216 or to a hardwired network through Ethernet adapter 218 .", "Network control module may be an intelligent module with its own computing system and memory including cache.", "Alternatively, it may be implemented as firmware or software running on CPU 202 .", "Likewise the keyboard 210 , display 212 memory system 206 may all be intelligent subsystems communicating over bus 208 .", "One skilled in the art is well aware of the many variations possible in the design of a computing system performing the logical operations of the various embodiments of the present invention.", "[0036] Computing system 200 , typically includes at least some form of computer-readable media.", "Computer readable media can be any available media that can be accessed by the computing system 200 .", "By way of example, and not limitation, computer-readable media might comprise computer storage media and communication media.", "[0037] Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data.", "Computer storage media includes, but is not limited to, RAM, ROM, EPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD), magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or other optical storage devices, or any other medium that can be used to store the desired information and that can be accessed by the computing system 200 .", "[0038] Communication media typically embodies computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media.", "The term “modulated data signal”", "means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal.", "By way of example, and not limitation, communication media includes wired media such as an optical fiber network, a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared, and other wireless media.", "Combinations of any of the above should also be included within the scope of computer-readable media.", "Computer-readable media may also be referred to as computer program product.", "[0039] FIG. 3 illustrates two computing systems 302 and 304 in a logical bus consisting of two bus daemons with their associated client and service applications.", "The computing systems are in a multicast group such as the group shown in FIG. 1 .", "Client applications in the computing systems discover service applications during a discovery phase.", "After client applications have discovered service applications and asked the bus daemons to connect, they may pass remote procedure calls and replies between their clients and servers using TCP messages orchestrated by the bus daemons.", "Name service module 307 works with bus daemon 306 to send UDP advertisement messages from name service 307 in response to discovery requests by bus daemon 306 during the discovery phase.", "Likewise name service module 309 works with bus daemon 308 to send the UDP advertisement messages from name service 309 , in response to discovery requests by bus daemon 308 during the discovery phase.", "If, as a result of discovery messages, a client application on either computing system decides it wants to use a service application on the other computing system, it will ask the bus daemons to connect and exchange information.", "After the bus daemons have exchanged information and established peer-to-peer communications, the bus daemons are said to be joined.", "Now client applications in one computing system 302 or 304 may pass remote procedure calls to server applications in the other computing system, or vice versa.", "[0040] Each application program using a logical bus has a client application, a server application or a combination thereof to communicate with its local bus daemon and thereby communicate with other service applications in other computing systems.", "For example, a SeaAdventure game, application program in computing system 302 has a client application part 314 and service application part 312 , while another instance of the SeaAdventure game, application program in computing system 304 has client application part 322 and service application part 324 .", "Once the bus daemons 306 and 308 are joined, the sense of client or service application is unimportant.", "The client and service distinction is important only in the service discovery phase to indicate what system is requesting and what system is responding.", "Once the busses are joined, the client and service applications at computing system 302 or 304 can be viewed as a merged client/service application, or in this case a SeaAdventure game, application.", "Now if either client application 314 or service application 312 wishes to execute a remote procedure call at service application 324 or client application 322 , and if bus daemon 306 is joined with bus daemon 308 , bus daemon 306 will build a TCP message to pass the remote procedure call to bus daemon 308 .", "Bus daemon 308 in turn passes the procedure call to the desired client or service application 322 or 324 .", "Any return information is processed in an inverse fashion.", "Likewise if client application 322 or service application 324 in computing system 304 wishes to execute a remote procedure call at client application 314 or service application 312 in computing system 302 , bus daemon 308 will build a TCP message to pass the remote procedure call to bus daemon 306 .", "Bus daemon 306 in turn passes the procedure call to service application 312 or client application 314 .", "Return information is processed in an inverse fashion.", "[0041] If bus daemons 306 and 308 have not joined when the mobile computing systems come with wireless range of each other, and an instance of the SeaAdventure game, service application 312 is running at computing system 302 with the bus daemon 306 , the name service 307 periodically advertises the availability of the instance of SeaAdventure game, service application by multicasting a UDP Advertise message effectively announcing, “I have an instance of a service application with well-known-name attribute, SeaAdventure.”", "The UDP message with the GUID, IP ADDRESS, PORT for bus daemon 306 along with the well-known-name attribute and instance attribute of the service application 312 is multicast to all bus daemons of the computing systems within range of access point 310 at a local wireless network in a coffee shop, for example.", "The UDP message from name service 307 is received by all name services within range of the access point 310 that are monitoring the multicast address.", "Particularly, name service module 309 now knows that service application 312 for SeaAdventure game is available through bus daemon 306 in computing system 302 .", "[0042] Likewise, if a an instance of SeaAdventure game, service application 324 is running at computing system 304 with the bus daemon 308 , the name service 309 periodically advertises the availability of SeaAdventure game, service application by multicasting a UDP message effectively saying, “I have an instance of a service application with well-known-name attribute, SeaAdventure.”", "The UDP message with the GUID, IP ADDRESS, PORT for bus daemon 308 along with the well-known-name attribute and instance attribute of the service application 324 is multicast to all bus daemons of the mobile computing systems within range of access point 310 .", "The UDP message from name service 309 is received by all name services within range of the access point 310 that are monitoring the multicast IP address.", "Name service module 307 now knows that service application 324 for SeaAdventure game is available through bus daemon 308 in computing system 304 .", "Either client application ( 314 or 322 ) may ask their respective bus daemons to connect to the other in which case the bus daemons are joined into a logical bus.", "[0043] The client and server application nomenclature is symmetrical.", "Both client and server application parts of an application such as SeaAdventure game in this example are part of the same program running on different computing systems.", "Once the discovery phase is complete, and the bus daemons are joined, the client and server applications in a steady-state phase of operation are linked to each other and their remote procedure calls and replies flow through the bus daemons between the separate computing systems.", "[0044] FIG. 4 illustrates a typical conversation between bus daemons such as those in FIG. 3 during the operation flow for discovering bus daemons having access to service applications with a well-known-name attribute.", "This discovery conversation is initiated by a service application 402 sending an ADVERTISE request 404 to bus daemon 406 requesting the bus daemon to advertise the availability of a Well-Known-Name service application.", "This happens when an instance of the Well-Known-Name service application has just attached itself to the bus daemon.", "Bus daemon 406 with its name service module builds the UDP IS-AT message and multicasts message instance 408 of the IS-AT message to the multicast group.", "The UDP message includes a KEEP ALIVE timer count.", "Bus daemon 406 also decrements the timer count to establish KEEP ALIVE interval.", "Whenever the KEEP ALIVE interval is decremented to a configurable value, the name service at bus daemon 406 will re-advertise the service application by generating new IS-AT messages, for example message instances 414 , 426 and 427 .", "This periodic re-advertisement happens as long as service application 402 is attached to the bus daemon 406 and allows bus daemons that have missed prior advertisements to receive them, or bus daemons newly arrived on a network segment to likewise receive them.", "If the service application 402 closes, the KEEP ALIVE timer count is set to zero, and bus daemon 406 no longer multicasts IS-AT message for service application 402 .", "Accordingly, service application 402 can enter or leave participation in the Well-Known-Name application.", "[0045] In FIG. 4 , bus daemon 416 arrives in the local proximity and has a client application 418 that is interested in connecting to an instance of a service application with a well-known-name attribute.", "Client application 418 asks its bus daemon 416 to discover any instances of service applications having the Well-Known-Name.", "Name service module of the bus daemon 416 sends instance 420 of a WHO-HAS message.", "If service application 402 is active and has the Well-Known-Name attribute, name service module of bus daemon 406 constructs an IS-AT message indicating that an instance of a service application with the Well-Known-Name attribute is at bus daemon 406 .", "The name service of bus daemon 406 sends a packet of instance 422 of the IS-AT message to the multicast group IP address.", "[0046] Bus daemon 416 receives the IS-AT message from the name service component of bus daemon 406 .", "The Well-Known-Name is entered in the cache of names and bus daemon addresses at bus daemon 416 .", "The availability of service application 402 is communicated to client application 418 via FOUND-NAME message instance 424 .", "The discovery phase is completed.", "If client application 418 chooses to ask the daemons to connect, service application 402 and client application 418 will be able to send remote procedure calls and procedure results using TCP messages.", "Bus daemon 406 will continue to periodically multicast IS-AT messages according to the KEEP ALIVE interval with renewed timer counts to advise other bus daemons of the instance of the Well-Known-Name service application 402 .", "The TCP communication between bus daemons may be ended by one of the bus daemons sending a FIN message under control of either the client or service application.", "If service application 402 should close, this fact is advertised by sending an IS-AT message with a zero timer count.", "In this way, client applications and service applications may enter or leave participation in a well-known-name program at will without disrupting the operation of the program.", "[0047] The exemplary conversation between computing systems in a multicast group, as depicted in FIG. 4 and described immediately above, is performed by bus daemons and their name service modules working together to execute the operation flows shown in FIGS. 5-8 .", "A bus daemon in its computing system, when prompted by a request from a service application in FIG. 5 or client application in FIG. 6 , acts to initiate a multicast operation from a responder in the daemon's name service module.", "FIG. 7 illustrates the operation flow of the responder.", "FIG. 8 illustrates the operation flow of a daemon in the computing system notifying its client application that a service application has been found.", "[0048] The logical operations in the operation flow diagrams of the various embodiments of the present invention are implemented (1) as a sequence of computer implemented acts or program modules running on a computing system and/or (2) as interconnected machine logic circuits or circuit modules within the computing system.", "The implementation is a matter of choice dependent on the performance requirements of the computing system implementing the invention.", "Accordingly, the logical operations making up the embodiments of the present invention described herein are referred to variously as operations, structural devices, acts or modules.", "It will be recognized by one skilled in the art that these operations, structural devices, acts and modules may be implemented in software, in firmware, in special purpose digital logic, and any combination thereof without deviating from the spirit and scope of the present invention as recited within the claims attached hereto.", "[0049] In FIG. 5 , advertise operation 502 at the bus daemon receives from a service application a request to advertise attribute information about the service application.", "The advertise request corresponds to discovery request 404 ( FIG. 4 ).", "Advertise operation 502 saves the service application well-known-name, being advertised, in the application name cache 504 and calls the name service module 506 of the bus daemon.", "Name service module 506 saves the advertised well-known-name in the name service cache 508 and initiates a discovery operation request, which in this case is an ADVERTISE operation request, at multicast request operation 510 .", "Multicast request operation 510 sends the ADVERTISE operation request to a responder module in the name service module.", "The responder will multicast a discovery message containing the well-known-name attribute of the service application being advertised.", "[0050] In FIG. 6 , FIND-NAME operation 602 at the bus daemon receives from a client application a FIND-NAME message 419 ( FIG. 4 ) requesting the bus daemon to find a service application with a given well-known-name attribute.", "In one embodiment the given well-known-name attribute is the well-known-name prefix of the peer application making the discovery request.", "FIND-NAME operation 602 saves the client application well-known-name in the daemon's interested-client-applications name list 604 and calls the name service module 606 of the bus daemon.", "Name service module 606 initiates a discovery operation request, which in this case is a FIND-NAME operation request, at multicast request operation 608 .", "Multicast request operation 608 sends a FIND-NAME operation request to a responder module in the name service.", "The responder will multicast a discovery message containing the well-known-name prefix attribute of the service application being sought by the client application.", "[0051] FIG. 7 shows the operational flow of the responder module in the name service.", "The responder, like the bus daemon and name service, may come up when the computing system powers on and may stay up until the computing system powers off.", "Multiple responders are allowed on any given computing system.", "The operational flow begins at wait operation 702 .", "Wait operation 702 is waiting for receipt of a timer event, an operation request event or a UDP packet event.", "Event-type test operation 704 detects the type of event received by the wait operation 702 .", "If the event is an operation request event, the operation flow branches from event-type test operation 704 to operation-type detect module 706 .", "If the event is a UDP packet event, the operation flow branches to message-type detect module 708 .", "If the event is a timer event, the operation flow branches to the timer-expired detect module 710 .", "[0052] When the event is an operation request event, operation-type detect module 706 tests whether the operation request is a FIND-NAME operation request or an ADVERTISE operation request.", "If it is an ADVERTISE operation request, the operation flow branches from the operation-type detect module 706 to the IS-AT operation 712 .", "IS-AT operation 712 formats and sends a discovery message, in this case an IS-AT message, e.g. message 408 ( FIG. 4 ), effectively saying for its associated bus daemon, “I have <org.example.Well-Known-Name.Instance>", "service application.”", "From IS-AT operation 712 , the operation flow returns to wait operation 702 .", "[0053] If the operation request is a FIND-NAME operation request, the operation flow branches from the operation-type detect module 706 to the WHO-HAS operation 714 .", "WHO-HAS operation 714 formats and sends a discovery message, in this case a WHO-HAS message, e.g. message instance 420 ( FIG. 4 ), effectively asking for a bus daemon, “Who has <org.example.Well-Known-Name.*>", "service application? Then the operation flow returns to wait operation 702 . [0054] When the event is receipt of a UDP Packet from a remote bus daemon, message-type detect module 708 tests whether the UDP packet is an IS-AT message or a WHO-HAS message. If the UDP packet is an IS-AT message, the operation flow branches from the message-type detect module 708 to notify-daemon operation 716 . Notify operation 716 notifies the bus daemon associated. with responder that an IS-AT message for <org.example.Well-Known-Name.Instance>", "service application has been received, and the service application is available through a bus daemon at IPADDRESS,PORT in a remote computing system. [0055] The IS-AT UDP packet is generated at a remote computing system as a result of either an ADVERTISE operation request at a remote bus daemon or as a result of WHO-HAS UDP packet being received at the name service of the remote bus daemon. In either case the receipt of an IS-AT message by a name service at a home bus daemon in the user's computing system is handled by the responder's notify-daemon operation 716 . Notify operation 716 notifies the home bus daemon an instance of a service application with a well-known-name attribute is available for interested client applications (if any) attached to the home bus daemon. The operational flow of the bus daemon in response to the notification is shown in FIG. 8 described hereinafter. After the notify-daemon operation 716 in FIG. 7 , the operational flow returns to wait operation 702 . [0056] If the UDP packet from a remote bus daemon is a WHO-HAS message the operational flow branches from message-type detect module 708 to “have-name”", "test operation 718 .", "If the bus daemon does not have an instance of a service application with a well-known-name attribute as asked for in the WHO-HAS message, the operation flow branches NO from the have-name test operation 718 and returns to wait operation 702 to wait for the next event.", "If the bus daemon has an instance of a service application with the well-known-name attribute sought by the WHO-HAS message, the operation flow branches YES to IS-AT operation 712 .", "IS-AT operation 712 formats and sends an IS-AT message saying the home bus daemon has an instance of the well-known-named service application.", "IS-AT message instance 422 ( FIG. 4 ) is an example of an IS-AT message being returned in response to a WHO-HAS message.", "Note that IS-AT operation 712 will send an IS-AT message in response to an ADVERTISE operation request or an appropriate WHO-HAS packet event where the have-name test 718 is satisfied.", "After the IS-AT message is sent, the operation flow returns to wait operation 702 .", "[0057] When the event is a timer event, timer-expired detect module 710 detects whether the expired timer event was a retry timer or a keep-alive timer.", "If the timer event is a keep-alive timer event, the operation flow branches from timer-expired detect module 710 to keep-alive operation 720 .", "Keep-alive operation formats and sends an IS-AT message, e.g. message instances 414 , 426 and 427 , for all advertised names of service applications currently being advertised by a name service for a bus daemon.", "Even if a bus daemon sending the IS-AT message has joined with another bus daemon as a result of an earlier discovery process, the keep-alive operation will continue to provide an opportunity for other bus daemons in the IP multicast group to join with the bus daemon.", "From keep-alive operation 720 the operation flow returns to wait operation 702 .", "[0058] If the timer event is a retry timer event, the operation flow branches from timer-expired detect module 710 to retry operation 722 .", "Retry operation 722 resends a WHO-HAS message, e.g. messages instances 428 and 429 , seeking an instance of a well-known-named service applications currently being sought by a name service for a bus daemon with a client application seeking the named service applications.", "Even if the bus daemon retrying the WHO-HAS message has joined, with another bus daemon as a result of an earlier discovery process, the retry operation will continue to provide an opportunity for other bus daemons in the multicast group to join with the bus daemon by retrying the WHO-HAS message.", "From retry operation 722 .", "the operation flow returns to wait operation 702 .", "[0059] FIG. 8 illustrates the operation flow of a bus daemon in the computing system notifying its client application that an instance of a service application with a requested well-known-name attribute has been found.", "Notification operation 802 at the daemon receives notification from notify-daemon operation 716 in the responder of daemon's name service that the service application with the well-known-name attribute the same as the well-known-name prefix in a FIND-NAME request is available.", "The same-name operation 802 saves the service application's well-known-name in a found-name list in the daemon's found-name cache 804 .", "Notification operation 802 also saves the IPADDRESS,PORT of the bus daemon where the desired service application is located.", "Found-name operation 806 sends a FOUND-NAME message, e.g. message instance 424 ( FIG. 4 ), from the daemon to signal interested client applications of a found-name.", "The FOUND-NAME message includes the name of same named service application that has been found and the IPADDRESS,PORT of its bus daemon.", "This completes the discovery phase for the client application that initiated the FIND-NAME request.", "[0060] Although the invention has been described in language specific to computer structural features, methodological acts and computer processes on computer readable media, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific structures, acts or media described.", "As an example, other logical operations may be included in the bus daemon discovery process.", "Also to the extent FIGS. 3 and 4 have been described as conversations between two computing systems, such conversations will typically be occurring in parallel amongst multiple computing systems in an IP multicast group.", "Therefore, the specific structural features, acts and media are disclosed as exemplary embodiments implementing the claimed invention.", "[0061] The various embodiments described above are provided by way of illustration only and should not be construed to limit the invention.", "Those skilled in the art will readily recognize various modifications and changes that may be made to the present invention without following the example embodiments and applications illustrated and described herein, and without departing from the spirit and scope of the present invention, which is set forth in the following claims." ]
CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is a divisional application of and claims the priority benefit of a prior application Ser. No. 13/402,883, filed on Feb. 23, 2012, now allowed, which claims the priority benefit of Taiwan application serial no. 100142006, filed on Nov. 17, 2011. The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of specification. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The invention relates to a pixel structure and a manufacturing method thereof. [0004] 2. Description of Related Art [0005] In general, a pixel structure of a liquid crystal display (LCD) includes a thin film transistor (TFT) and a pixel electrode. The TFT serves as a switching device of an LCD unit. To control each individual pixel structure, a certain pixel is usually selected according to a corresponding scan line and a corresponding data line, and display information corresponding to the certain pixel is displayed through providing an appropriate operating voltage. The pixel structure further includes a storage capacitor, such that the pixel structure can be equipped with a voltage-retaining function. Namely, the storage capacitor can store the applied operating voltage to stabilize the display image of the pixel structure. [0006] To form the storage capacitor in the pixel structure, a capacitor electrode is often required in the pixel structure. However, in order to increase the capacitance of the storage capacitor, the area occupied by the capacitor electrode need be expanded, thus reducing the aperture ratio of the pixel structure. [0007] At present, a pixel structure in which the capacitor electrode is disposed below the data line has been proposed to increase the aperture ratio of the pixel structure. However, the capacitor electrode and the data line which are overlapped increase the loading of the pixel structure. Therefore, in the pixel structure, the required power consumption for driving the display panel is increased in the pixel structure. SUMMARY OF THE INVENTION [0008] The invention is directed to a pixel structure and a manufacturing method thereof, and the pixel structure can have a high aperture ratio without increasing the loading of the pixel structure. [0009] In the invention, a pixel structure that includes a first electrode, a first insulation layer, a gate, a second electrode, a second insulation layer, a semiconductor layer, a source and a drain, a third electrode, a third insulation layer, and a pixel electrode is provided. The first electrode is located on a substrate. The first insulation layer covers the first electrode. The gate is located on the first insulation layer. The second electrode is located on the first insulation layer above the first electrode. The second insulation layer covers the gate and the second electrode. The semiconductor layer is located on the second insulation layer above the gate. The source and the drain are located on the semiconductor layer. Here, the gate, the semiconductor layer, the source, and the drain together constitute a TFT. The third electrode is located on the second insulation layer above the second electrode and the third electrode is electrically connected to the first electrode. Here, the first electrode, the second electrode, and the third electrode together constitute a capacitor. The third insulation layer covers the source, the drain, and the third electrode. The pixel electrode is located on the third insulation layer and electrically connected to the drain. [0010] In the invention, a manufacturing method of a pixel structure is also provided. In the manufacturing method, a first conductive layer is formed on a substrate, and the first conductive layer includes a first electrode. A first insulation layer is formed on the first conductive layer. A second conductive layer is formed on the first insulation layer. The second conductive layer includes a gate and a second electrode, and the second electrode is located above the first electrode. A second insulation layer is formed on the second conductive layer. A semiconductor layer is formed on the second insulation layer above the gate. A third conductive layer is formed on the second insulation layer. The third conductive layer includes a source, a drain, and a third electrode. The source and the drain are located on the semiconductor layer, and the third electrode is located above the second electrode and electrically connected to the first electrode. Here, the gate, the semiconductor layer, the source, and the drain together constitute a TFT, and the first electrode, the second electrode, and the third electrode together constitute a capacitor. A third insulation layer is formed on the third conductive layer. A pixel electrode is formed on the third insulation layer, and the pixel electrode is electrically connected to the drain. [0011] Based on the above, the capacitor described herein is constituted by the first electrode, the second electrode, and the third electrode, and the first electrode is located below the first insulation layer that is below the second electrode. Hence, in the invention, the storage capacitance of the capacitor can be increased without negatively affecting the aperture ratio of the pixel structure; what is more, a display with high resolution can be formed. From another aspect, since the first, second, and third electrodes of the capacitor are not configured below the data line, the capacitor described herein does not lead to an increase in the loading of the pixel structure. [0012] In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanying figures are described in detail below. BRIEF DESCRIPTION OF THE DRAWINGS [0013] The accompanying drawings are included to provide further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments and, together with the description, serve to explain the principles of the invention. [0014] FIG. 1A through 1I are schematic cross-sectional views illustrating a process of fabricating a pixel structure according to an embodiment of the invention. [0015] FIG. 2 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. Here, FIG. 2 is taken along section lines I-I′ and II-II′ corresponding to the cross-sectional views in FIG. 1A to FIG. 1I . [0016] FIG. 3 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. [0017] FIG. 4 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 3 . [0018] FIG. 5 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. [0019] FIG. 6 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 5 . [0020] FIG. 7 is a schematic cross-sectional view illustrating a pixel structure according to another embodiment of the invention. [0021] FIG. 8 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. DESCRIPTION OF EMBODIMENTS [0022] FIG. 1A through 1I are schematic cross-sectional views illustrating a process of fabricating a pixel structure according to an embodiment of the invention. FIG. 2 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. Here, FIG. 2 is taken along section lines I-I′ and II-II′ corresponding to the cross-sectional views in FIG. 1A to FIG. 1I . [0023] With reference to FIG. 1A , in the present embodiment, a first conductive layer M 1 is formed on a substrate 100 , and the first conductive layer M 1 includes a first electrode E 1 . The substrate 100 can be made of glass, quartz, an organic polymer, an opaque/reflective material (such as a conductive material, wafer, ceramics, or any other appropriate material), or any other appropriate material. A material of the first conductive layer M 1 (the first electrode E 1 ) includes metal, an alloy, metal nitride, metal oxide, metal oxynitride, another appropriate material, or a layer in which a metal material and any other conductive material are stacked together. A method of forming the first conductive layer M 1 (the first electrode E 1 ) includes performing a deposition process to deposit a conductive material layer and performing a photolithography and etching process to pattern the conductive material layer, for instance. [0024] With reference to FIG. 1B , a first insulation layer 102 is formed on the first conductive layer M 1 (the first electrode E 1 ). A material of the first insulation layer 102 includes an inorganic insulation material (e.g., silicon oxide, silicon nitride, silicon oxynitride, or any other appropriate dielectric material) or an organic insulation material. The first insulation layer 102 is formed by performing a chemical vapor deposition (CVD) process, a physical vapor deposition (PVD) process, or a coating process, for instance. [0025] With reference to FIG. 1C , a second conductive layer M 2 is formed on the first insulation layer 102 , and the second conductive layer M 2 includes a gate G and a second electrode E 2 that is located above the first electrode E 1 . According to the present embodiment, the second conductive layer M 2 further includes a scan line SL and an electrode line CL (as shown in FIG. 2 ); the scan line SL is electrically connected to the gate G, and the electrode line CL is electrically connected to the second electrode E 2 . A material of the second conductive layer M 2 includes metal, an alloy, metal nitride, metal oxide, metal oxynitride, another appropriate material, or a layer in which a metal material and any other conductive material are stacked together. A method of forming the second conductive layer M 2 includes performing a deposition process to deposit a conductive material layer and performing a photolithography and etching process to pattern the conductive material layer, for instance. [0026] With reference to FIG. 1D , a second insulation layer 104 is formed on the second conductive layer M 2 (the gate G and the second electrode E 2 ). A material of the second insulation layer 104 includes an inorganic insulation material (e.g., silicon oxide, silicon nitride, silicon oxynitride, or any other appropriate dielectric material) or an organic insulation material. The second insulation layer 104 is formed by performing a CVD process, a PVD process, or a coating process, for instance. [0027] With reference to FIG. 1E , a semiconductor layer SE is formed on the second insulation layer 104 above the gate G. According to the present embodiment, the semiconductor layer SE includes a channel layer CH and an ohmic contact layer OH. A method of forming the semiconductor layer SE includes performing a deposition process to sequentially deposit a channel material layer and an ohmic contact material layer and performing a photolithography and etching process to pattern the two material layers, for instance. However, the semiconductor layer SE is not required to include both the channel layer CH and the ohmic contact layer OH in the invention; namely, according to another embodiment, the semiconductor layer SE may merely contain the channel layer CH. [0028] With reference to FIG. 1F , the second insulation layer 104 is patterned to faun a contact opening C 1 that exposes the first electrode E 1 . [0029] With reference to FIG. 1G , a third conductive layer M 3 is formed on the second insulation layer 104 , and the third conductive layer M 3 includes a source S, a drain D, and a third electrode E 3 . Here, the third conductive layer M 3 may further include a data line DL. The source S and the drain D are located on the semiconductor layer SE, the third electrode E 3 is located above the second electrode E 2 , and the data line DL is electrically connected to the source S. According to the present embodiment, the drain D is connected to the third electrode E 3 ; thus, the drain D is electrically connected to the third electrode E 3 . Here, the gate G, the semiconductor layer SE, the source S, and the drain D together constitute a TFT T, and the first, second, and third electrodes E 1 , E 2 , and E 3 together constitute a capacitor CS. Besides, the third electrode E 3 is electrically connected to the first electrode E 1 through the contact opening C 1 formed in the second insulation layer 104 . [0030] It should be mentioned that the contact opening C 1 for electrically connecting the first and third electrodes E 1 and E 3 is disposed at a region away from the TFT T according to the present embodiment. This is mainly to prevent the contact opening C 1 from causing short circuit between the electrode (the gate G) of the TFT T and the electrode (the second electrode E 2 ) of the capacitor CS. However, the location of the contact opening C 1 is not limited in the invention; as a matter of fact, the contact opening C 1 can be located at any region where the first and third electrodes E 1 and E 3 are overlapped without causing short circuit between the TFT T and the capacitor CS. [0031] With reference to FIG. 1H , a third insulation layer ( 106 , 110 ) is formed on the third conductive layer M 3 (the source S, the drain D, and the third electrode E 3 ). In the present embodiment, the third insulation layer includes a passivation layer 106 and a planarization layer 110 , which should not be construed as a limitation to the invention. In another embodiment, the third insulation layer may also contain one of the passivation layer 106 and the planarization layer 110 . The third insulation layer 110 , 106 is patterned to form a contact opening C 2 , and the contact opening C 2 exposes the third electrode E 3 . [0032] With reference to FIG. 1I , a pixel electrode PE is formed on the third insulation layer 106 , 110 , and the pixel electrode PE is electrically connected to the drain D. According to the present embodiment, the contact opening C 2 is located on and exposes the third electrode E 3 , and thus the pixel electrode PE can be electrically connected to the third electrode E 3 through the contact opening C 2 . Since the drain D is directly connected to the third electrode E 3 , the pixel electrode PE can be electrically connected to the drain D through the contact opening C 2 and the third electrode E 3 . The pixel electrode PE may be a transparent pixel electrode, a reflective pixel electrode, or a combination of the transparent pixel electrode and the reflective pixel electrode. A material of the transparent pixel electrode may include metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), aluminum tin oxide (ATO), aluminum zinc oxide (AZO), indium germanium zinc oxide, other suitable oxide, or a stacked layer having at least two of the above materials. The reflective pixel electrode is made of a metal material that is characterized by high reflectivity, for instance. [0033] The pixel structure formed by conducting the aforesaid method is shown in FIG. 1I and FIG. 2 , and the pixel structure includes the first electrode E 1 , the first insulation layer 102 , the gate G, the second electrode E 2 , the second insulation layer 104 , the semiconductor layer SE, the source S and the drain D, the third electrode E 3 , the third insulation layer 106 , 110 , and the pixel electrode PE. The first electrode E 1 is located on the substrate 100 . The first insulation layer 102 covers the first electrode E 1 . The gate G is located on the first insulation layer 102 . The second electrode E 2 is located on the first insulation layer 102 above the first electrode E 1 . The second insulation layer 104 covers the gate G and the second electrode E 2 . The semiconductor layer SE is located on the second insulation layer 104 above the gate G. The source S and the drain D are located on the semiconductor layer SE. The gate G, the semiconductor layer SE, the source S, and the drain D together constitute a TFT T. The third electrode E 3 is located on the second insulation layer 104 above the second electrode E 2 . Here, the third electrode E 3 is electrically connected to the first electrode E 1 , and the first electrode E 1 , the second electrode E 2 , and the third electrode E 3 together constitute the capacitor CS. The third insulation layer 106 , 110 covers the source S, the drain D, and the third electrode E 3 . The pixel electrode PE is located on the third insulation layer 110 and electrically connected to the drain D. [0034] It should be mentioned that the TFT T and the capacitor CS in the pixel structure shown in FIG. 2 are located at the edge portion of the pixel structure (the pixel electrode PE). However, the invention is not limited thereto, and the TFT T and the capacitor CS in another embodiment may be located at the central portion of the pixel structure (the pixel electrode PE). [0035] In view of the previous embodiments, the capacitor CS is constituted by the first electrode E 1 , the second electrode E 2 , and the third electrode E 3 , and the first electrode E 1 is located below the first insulation layer 102 that is below the second electrode E 2 . Hence, in the invention, the storage capacitance of the capacitor CS can be increased without negatively affecting the aperture ratio of the pixel structure. From another perspective, since the first, second, and third electrodes E 1 , E 2 , and E 3 of the capacitor CS are not overlapped with the data line DL, the capacitance of the capacitor CS does not interfere with the data line DL and thus does not increase the loading of the pixel structure. [0036] FIG. 3 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. FIG. 4 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 3 . With reference to FIG. 3 and FIG. 4 , the embodiment shown herein is similar to the embodiment shown in FIG. 2 , so that identical components in these figures will be denoted by the same numerals and will not be reiterated herein. In the present embodiment, the first conductive layer M 1 not only includes the first electrode E 1 but also includes a light shielding portion SH 1 . The light shielding portion SH 1 is correspondingly disposed below and at one side of the gate G but does not extend to an underside of the data line DL. Here, the light shielding portion SH 1 may be connected to the first electrode E 1 , and thus the light shielding portion SH 1 and the first electrode E 1 of the first conductive layer M 1 constitute a lump or block pattern. That is to say, the light shielding portion SH 1 extends from the first electrode E 1 to an underside of the gate G. [0037] The light shielding portion SH 1 disposed below the gate G may shield the light from the backside of the substrate 100 , so as to prevent the TFT T from generating photo-leakage current. In general, the liquid crystal is a non-self-illuminating display medium, and thus a backlight module is required to be additionally configured at the back side of the display panel for supplying the planar light source needed by the display panel. With the development of the display panel with high resolution, the light intensity of the backlight module need be improved to comply with the brightness standard required by the display panel with high resolution. Nonetheless, when the light intensity of the backlight module increases, the light is much more likely to cause photo-leakage current in the TFT in the display panel. Accordingly, the light shielding portion SH 1 is configured in the first conductive layer in the present embodiment, so as to prevent the light coming from the backside of the substrate 100 (i.e., the light of the backlight module) from generating photo-leakage current in the TFT T. In other words, the light coming from the backside of the substrate 100 (the light of the backlight module), after being blocked by the light shielding portion SH 1 and the gate G, can be precluded from entering the semiconductor layer SE, and thereby the issue of photo-leakage current does not arise in the TFT T. [0038] FIG. 5 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. FIG. 6 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 5 . With reference to FIG. 5 and FIG. 6 , the embodiment shown herein is similar to the embodiment shown in FIG. 2 , so that identical components in these figures will be denoted by the same numerals and will not be reiterated herein. In the present embodiment, the first conductive layer M 1 not only includes the first electrode E 1 but also includes a light shielding portion SH 1 and a light shielding portion SH 2 . The light shielding portions SH 1 and SH 2 are correspondingly disposed below and respectively at two sides of the gate G and extend to an underside of the data line DL. Here, the light shielding portions SH 1 and SH 2 may be connected to the first electrode E 1 , and thus the light shielding portions SH 1 and SH 2 and the first electrode E 1 of the first conductive layer M 1 constitute a lump or block pattern. [0039] Similarly, the light shielding portions SH 1 and SH 2 configured below the gate G may shield the light from the underside of the substrate 100 , so as to prevent the TFT T from generating photo-leakage current. In other words, the light coming from the underside of the substrate 100 (the light of the backlight module), after being blocked by the light shielding portions SH 1 and SH 2 and the gate G, can be precluded from entering the semiconductor layer SE, and thereby the issue of photo-leakage current does not arise in the TFT T. [0040] FIG. 7 is a schematic cross-sectional view illustrating a pixel structure according to another embodiment of the invention. FIG. 8 is a schematic top view illustrating a pixel structure according to an embodiment of the invention. Specifically, the cross-sectional view taken along the sectional lines I-I′ and II-II′ of FIG. 8 is shown in FIG. 7 . With reference to FIG. 7 and FIG. 8 , the embodiment shown herein is similar to the embodiment shown in FIG. 6 , so that identical components in these figures will be denoted by the same numerals and will not be reiterated herein. In this embodiment, the contact opening C 1 is located between the gate G and the second electrode E 2 . The gate G and the second electrode E 2 both belong to the second conductive layer M 2 ; therefore, when the contact opening C 1 is defined, the contact opening C 1 need be located at a region where the gate G and the second electrode E 2 are not located, so as to prevent the subsequent short circuit between the gate G and the second electrode E 2 . Besides, in the present embodiment, the contact opening C 2 is located above the contact opening C 1 . However, the contact opening C 2 is not necessarily located right above the contact opening C 1 in the invention. [0041] In light of the foregoing, the capacitor described herein is constituted by the first electrode, the second electrode, and the third electrode, and the first electrode is located below the first insulation layer that is below the second electrode. Hence, in the invention, the storage capacitance of the capacitor can be increased without negatively affecting the aperture ratio of the pixel structure. From another aspect, since none of the first, second, and third electrodes of the capacitor are configured below the data line, the capacitor described herein does not lead to an increase in the loading of the pixel structure. Moreover, the light shielding portion disposed below the gate may shield the light from the underside of the substrate, so as to prevent the TFT from generating photo-leakage current. [0042] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
A manufacturing method of pixel structure includes forming a first conductive layer on a substrate and forming a first insulation layer thereon; forming a second conductive layer on the first insulation layer; forming a second insulation layer on the second conductive layer; forming a semiconductor layer on the second insulation layer above the gate; forming a third conductive layer on the second insulation layer, wherein the gate, the semiconductor layer, the source, and the drain together constitute a thin film transistor, and the first electrode, the second electrode, and the third electrode together constitute a capacitor; forming a third insulation layer on the third conductive layer; and forming a pixel electrode on the third insulation layer, the pixel electrode being electrically connected to the drain.
Identify the most important claim in the given context and summarize it
[ "CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is a divisional application of and claims the priority benefit of a prior application Ser.", "No. 13/402,883, filed on Feb. 23, 2012, now allowed, which claims the priority benefit of Taiwan application serial no. 100142006, filed on Nov. 17, 2011.", "The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of specification.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] The invention relates to a pixel structure and a manufacturing method thereof.", "[0004] 2.", "Description of Related Art [0005] In general, a pixel structure of a liquid crystal display (LCD) includes a thin film transistor (TFT) and a pixel electrode.", "The TFT serves as a switching device of an LCD unit.", "To control each individual pixel structure, a certain pixel is usually selected according to a corresponding scan line and a corresponding data line, and display information corresponding to the certain pixel is displayed through providing an appropriate operating voltage.", "The pixel structure further includes a storage capacitor, such that the pixel structure can be equipped with a voltage-retaining function.", "Namely, the storage capacitor can store the applied operating voltage to stabilize the display image of the pixel structure.", "[0006] To form the storage capacitor in the pixel structure, a capacitor electrode is often required in the pixel structure.", "However, in order to increase the capacitance of the storage capacitor, the area occupied by the capacitor electrode need be expanded, thus reducing the aperture ratio of the pixel structure.", "[0007] At present, a pixel structure in which the capacitor electrode is disposed below the data line has been proposed to increase the aperture ratio of the pixel structure.", "However, the capacitor electrode and the data line which are overlapped increase the loading of the pixel structure.", "Therefore, in the pixel structure, the required power consumption for driving the display panel is increased in the pixel structure.", "SUMMARY OF THE INVENTION [0008] The invention is directed to a pixel structure and a manufacturing method thereof, and the pixel structure can have a high aperture ratio without increasing the loading of the pixel structure.", "[0009] In the invention, a pixel structure that includes a first electrode, a first insulation layer, a gate, a second electrode, a second insulation layer, a semiconductor layer, a source and a drain, a third electrode, a third insulation layer, and a pixel electrode is provided.", "The first electrode is located on a substrate.", "The first insulation layer covers the first electrode.", "The gate is located on the first insulation layer.", "The second electrode is located on the first insulation layer above the first electrode.", "The second insulation layer covers the gate and the second electrode.", "The semiconductor layer is located on the second insulation layer above the gate.", "The source and the drain are located on the semiconductor layer.", "Here, the gate, the semiconductor layer, the source, and the drain together constitute a TFT.", "The third electrode is located on the second insulation layer above the second electrode and the third electrode is electrically connected to the first electrode.", "Here, the first electrode, the second electrode, and the third electrode together constitute a capacitor.", "The third insulation layer covers the source, the drain, and the third electrode.", "The pixel electrode is located on the third insulation layer and electrically connected to the drain.", "[0010] In the invention, a manufacturing method of a pixel structure is also provided.", "In the manufacturing method, a first conductive layer is formed on a substrate, and the first conductive layer includes a first electrode.", "A first insulation layer is formed on the first conductive layer.", "A second conductive layer is formed on the first insulation layer.", "The second conductive layer includes a gate and a second electrode, and the second electrode is located above the first electrode.", "A second insulation layer is formed on the second conductive layer.", "A semiconductor layer is formed on the second insulation layer above the gate.", "A third conductive layer is formed on the second insulation layer.", "The third conductive layer includes a source, a drain, and a third electrode.", "The source and the drain are located on the semiconductor layer, and the third electrode is located above the second electrode and electrically connected to the first electrode.", "Here, the gate, the semiconductor layer, the source, and the drain together constitute a TFT, and the first electrode, the second electrode, and the third electrode together constitute a capacitor.", "A third insulation layer is formed on the third conductive layer.", "A pixel electrode is formed on the third insulation layer, and the pixel electrode is electrically connected to the drain.", "[0011] Based on the above, the capacitor described herein is constituted by the first electrode, the second electrode, and the third electrode, and the first electrode is located below the first insulation layer that is below the second electrode.", "Hence, in the invention, the storage capacitance of the capacitor can be increased without negatively affecting the aperture ratio of the pixel structure;", "what is more, a display with high resolution can be formed.", "From another aspect, since the first, second, and third electrodes of the capacitor are not configured below the data line, the capacitor described herein does not lead to an increase in the loading of the pixel structure.", "[0012] In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanying figures are described in detail below.", "BRIEF DESCRIPTION OF THE DRAWINGS [0013] The accompanying drawings are included to provide further understanding, and are incorporated in and constitute a part of this specification.", "The drawings illustrate exemplary embodiments and, together with the description, serve to explain the principles of the invention.", "[0014] FIG. 1A through 1I are schematic cross-sectional views illustrating a process of fabricating a pixel structure according to an embodiment of the invention.", "[0015] FIG. 2 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "Here, FIG. 2 is taken along section lines I-I′ and II-II′ corresponding to the cross-sectional views in FIG. 1A to FIG. 1I .", "[0016] FIG. 3 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "[0017] FIG. 4 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 3 .", "[0018] FIG. 5 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "[0019] FIG. 6 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 5 .", "[0020] FIG. 7 is a schematic cross-sectional view illustrating a pixel structure according to another embodiment of the invention.", "[0021] FIG. 8 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "DESCRIPTION OF EMBODIMENTS [0022] FIG. 1A through 1I are schematic cross-sectional views illustrating a process of fabricating a pixel structure according to an embodiment of the invention.", "FIG. 2 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "Here, FIG. 2 is taken along section lines I-I′ and II-II′ corresponding to the cross-sectional views in FIG. 1A to FIG. 1I .", "[0023] With reference to FIG. 1A , in the present embodiment, a first conductive layer M 1 is formed on a substrate 100 , and the first conductive layer M 1 includes a first electrode E 1 .", "The substrate 100 can be made of glass, quartz, an organic polymer, an opaque/reflective material (such as a conductive material, wafer, ceramics, or any other appropriate material), or any other appropriate material.", "A material of the first conductive layer M 1 (the first electrode E 1 ) includes metal, an alloy, metal nitride, metal oxide, metal oxynitride, another appropriate material, or a layer in which a metal material and any other conductive material are stacked together.", "A method of forming the first conductive layer M 1 (the first electrode E 1 ) includes performing a deposition process to deposit a conductive material layer and performing a photolithography and etching process to pattern the conductive material layer, for instance.", "[0024] With reference to FIG. 1B , a first insulation layer 102 is formed on the first conductive layer M 1 (the first electrode E 1 ).", "A material of the first insulation layer 102 includes an inorganic insulation material (e.g., silicon oxide, silicon nitride, silicon oxynitride, or any other appropriate dielectric material) or an organic insulation material.", "The first insulation layer 102 is formed by performing a chemical vapor deposition (CVD) process, a physical vapor deposition (PVD) process, or a coating process, for instance.", "[0025] With reference to FIG. 1C , a second conductive layer M 2 is formed on the first insulation layer 102 , and the second conductive layer M 2 includes a gate G and a second electrode E 2 that is located above the first electrode E 1 .", "According to the present embodiment, the second conductive layer M 2 further includes a scan line SL and an electrode line CL (as shown in FIG. 2 );", "the scan line SL is electrically connected to the gate G, and the electrode line CL is electrically connected to the second electrode E 2 .", "A material of the second conductive layer M 2 includes metal, an alloy, metal nitride, metal oxide, metal oxynitride, another appropriate material, or a layer in which a metal material and any other conductive material are stacked together.", "A method of forming the second conductive layer M 2 includes performing a deposition process to deposit a conductive material layer and performing a photolithography and etching process to pattern the conductive material layer, for instance.", "[0026] With reference to FIG. 1D , a second insulation layer 104 is formed on the second conductive layer M 2 (the gate G and the second electrode E 2 ).", "A material of the second insulation layer 104 includes an inorganic insulation material (e.g., silicon oxide, silicon nitride, silicon oxynitride, or any other appropriate dielectric material) or an organic insulation material.", "The second insulation layer 104 is formed by performing a CVD process, a PVD process, or a coating process, for instance.", "[0027] With reference to FIG. 1E , a semiconductor layer SE is formed on the second insulation layer 104 above the gate G. According to the present embodiment, the semiconductor layer SE includes a channel layer CH and an ohmic contact layer OH.", "A method of forming the semiconductor layer SE includes performing a deposition process to sequentially deposit a channel material layer and an ohmic contact material layer and performing a photolithography and etching process to pattern the two material layers, for instance.", "However, the semiconductor layer SE is not required to include both the channel layer CH and the ohmic contact layer OH in the invention;", "namely, according to another embodiment, the semiconductor layer SE may merely contain the channel layer CH.", "[0028] With reference to FIG. 1F , the second insulation layer 104 is patterned to faun a contact opening C 1 that exposes the first electrode E 1 .", "[0029] With reference to FIG. 1G , a third conductive layer M 3 is formed on the second insulation layer 104 , and the third conductive layer M 3 includes a source S, a drain D, and a third electrode E 3 .", "Here, the third conductive layer M 3 may further include a data line DL.", "The source S and the drain D are located on the semiconductor layer SE, the third electrode E 3 is located above the second electrode E 2 , and the data line DL is electrically connected to the source S. According to the present embodiment, the drain D is connected to the third electrode E 3 ;", "thus, the drain D is electrically connected to the third electrode E 3 .", "Here, the gate G, the semiconductor layer SE, the source S, and the drain D together constitute a TFT T, and the first, second, and third electrodes E 1 , E 2 , and E 3 together constitute a capacitor CS.", "Besides, the third electrode E 3 is electrically connected to the first electrode E 1 through the contact opening C 1 formed in the second insulation layer 104 .", "[0030] It should be mentioned that the contact opening C 1 for electrically connecting the first and third electrodes E 1 and E 3 is disposed at a region away from the TFT T according to the present embodiment.", "This is mainly to prevent the contact opening C 1 from causing short circuit between the electrode (the gate G) of the TFT T and the electrode (the second electrode E 2 ) of the capacitor CS.", "However, the location of the contact opening C 1 is not limited in the invention;", "as a matter of fact, the contact opening C 1 can be located at any region where the first and third electrodes E 1 and E 3 are overlapped without causing short circuit between the TFT T and the capacitor CS.", "[0031] With reference to FIG. 1H , a third insulation layer ( 106 , 110 ) is formed on the third conductive layer M 3 (the source S, the drain D, and the third electrode E 3 ).", "In the present embodiment, the third insulation layer includes a passivation layer 106 and a planarization layer 110 , which should not be construed as a limitation to the invention.", "In another embodiment, the third insulation layer may also contain one of the passivation layer 106 and the planarization layer 110 .", "The third insulation layer 110 , 106 is patterned to form a contact opening C 2 , and the contact opening C 2 exposes the third electrode E 3 .", "[0032] With reference to FIG. 1I , a pixel electrode PE is formed on the third insulation layer 106 , 110 , and the pixel electrode PE is electrically connected to the drain D. According to the present embodiment, the contact opening C 2 is located on and exposes the third electrode E 3 , and thus the pixel electrode PE can be electrically connected to the third electrode E 3 through the contact opening C 2 .", "Since the drain D is directly connected to the third electrode E 3 , the pixel electrode PE can be electrically connected to the drain D through the contact opening C 2 and the third electrode E 3 .", "The pixel electrode PE may be a transparent pixel electrode, a reflective pixel electrode, or a combination of the transparent pixel electrode and the reflective pixel electrode.", "A material of the transparent pixel electrode may include metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), aluminum tin oxide (ATO), aluminum zinc oxide (AZO), indium germanium zinc oxide, other suitable oxide, or a stacked layer having at least two of the above materials.", "The reflective pixel electrode is made of a metal material that is characterized by high reflectivity, for instance.", "[0033] The pixel structure formed by conducting the aforesaid method is shown in FIG. 1I and FIG. 2 , and the pixel structure includes the first electrode E 1 , the first insulation layer 102 , the gate G, the second electrode E 2 , the second insulation layer 104 , the semiconductor layer SE, the source S and the drain D, the third electrode E 3 , the third insulation layer 106 , 110 , and the pixel electrode PE.", "The first electrode E 1 is located on the substrate 100 .", "The first insulation layer 102 covers the first electrode E 1 .", "The gate G is located on the first insulation layer 102 .", "The second electrode E 2 is located on the first insulation layer 102 above the first electrode E 1 .", "The second insulation layer 104 covers the gate G and the second electrode E 2 .", "The semiconductor layer SE is located on the second insulation layer 104 above the gate G. The source S and the drain D are located on the semiconductor layer SE.", "The gate G, the semiconductor layer SE, the source S, and the drain D together constitute a TFT T. The third electrode E 3 is located on the second insulation layer 104 above the second electrode E 2 .", "Here, the third electrode E 3 is electrically connected to the first electrode E 1 , and the first electrode E 1 , the second electrode E 2 , and the third electrode E 3 together constitute the capacitor CS.", "The third insulation layer 106 , 110 covers the source S, the drain D, and the third electrode E 3 .", "The pixel electrode PE is located on the third insulation layer 110 and electrically connected to the drain D. [0034] It should be mentioned that the TFT T and the capacitor CS in the pixel structure shown in FIG. 2 are located at the edge portion of the pixel structure (the pixel electrode PE).", "However, the invention is not limited thereto, and the TFT T and the capacitor CS in another embodiment may be located at the central portion of the pixel structure (the pixel electrode PE).", "[0035] In view of the previous embodiments, the capacitor CS is constituted by the first electrode E 1 , the second electrode E 2 , and the third electrode E 3 , and the first electrode E 1 is located below the first insulation layer 102 that is below the second electrode E 2 .", "Hence, in the invention, the storage capacitance of the capacitor CS can be increased without negatively affecting the aperture ratio of the pixel structure.", "From another perspective, since the first, second, and third electrodes E 1 , E 2 , and E 3 of the capacitor CS are not overlapped with the data line DL, the capacitance of the capacitor CS does not interfere with the data line DL and thus does not increase the loading of the pixel structure.", "[0036] FIG. 3 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "FIG. 4 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 3 .", "With reference to FIG. 3 and FIG. 4 , the embodiment shown herein is similar to the embodiment shown in FIG. 2 , so that identical components in these figures will be denoted by the same numerals and will not be reiterated herein.", "In the present embodiment, the first conductive layer M 1 not only includes the first electrode E 1 but also includes a light shielding portion SH 1 .", "The light shielding portion SH 1 is correspondingly disposed below and at one side of the gate G but does not extend to an underside of the data line DL.", "Here, the light shielding portion SH 1 may be connected to the first electrode E 1 , and thus the light shielding portion SH 1 and the first electrode E 1 of the first conductive layer M 1 constitute a lump or block pattern.", "That is to say, the light shielding portion SH 1 extends from the first electrode E 1 to an underside of the gate G. [0037] The light shielding portion SH 1 disposed below the gate G may shield the light from the backside of the substrate 100 , so as to prevent the TFT T from generating photo-leakage current.", "In general, the liquid crystal is a non-self-illuminating display medium, and thus a backlight module is required to be additionally configured at the back side of the display panel for supplying the planar light source needed by the display panel.", "With the development of the display panel with high resolution, the light intensity of the backlight module need be improved to comply with the brightness standard required by the display panel with high resolution.", "Nonetheless, when the light intensity of the backlight module increases, the light is much more likely to cause photo-leakage current in the TFT in the display panel.", "Accordingly, the light shielding portion SH 1 is configured in the first conductive layer in the present embodiment, so as to prevent the light coming from the backside of the substrate 100 (i.e., the light of the backlight module) from generating photo-leakage current in the TFT T. In other words, the light coming from the backside of the substrate 100 (the light of the backlight module), after being blocked by the light shielding portion SH 1 and the gate G, can be precluded from entering the semiconductor layer SE, and thereby the issue of photo-leakage current does not arise in the TFT T. [0038] FIG. 5 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "FIG. 6 is a schematic cross-sectional view illustrating the pixel structure taken along section lines I-I′ and II-II′ depicted in FIG. 5 .", "With reference to FIG. 5 and FIG. 6 , the embodiment shown herein is similar to the embodiment shown in FIG. 2 , so that identical components in these figures will be denoted by the same numerals and will not be reiterated herein.", "In the present embodiment, the first conductive layer M 1 not only includes the first electrode E 1 but also includes a light shielding portion SH 1 and a light shielding portion SH 2 .", "The light shielding portions SH 1 and SH 2 are correspondingly disposed below and respectively at two sides of the gate G and extend to an underside of the data line DL.", "Here, the light shielding portions SH 1 and SH 2 may be connected to the first electrode E 1 , and thus the light shielding portions SH 1 and SH 2 and the first electrode E 1 of the first conductive layer M 1 constitute a lump or block pattern.", "[0039] Similarly, the light shielding portions SH 1 and SH 2 configured below the gate G may shield the light from the underside of the substrate 100 , so as to prevent the TFT T from generating photo-leakage current.", "In other words, the light coming from the underside of the substrate 100 (the light of the backlight module), after being blocked by the light shielding portions SH 1 and SH 2 and the gate G, can be precluded from entering the semiconductor layer SE, and thereby the issue of photo-leakage current does not arise in the TFT T. [0040] FIG. 7 is a schematic cross-sectional view illustrating a pixel structure according to another embodiment of the invention.", "FIG. 8 is a schematic top view illustrating a pixel structure according to an embodiment of the invention.", "Specifically, the cross-sectional view taken along the sectional lines I-I′ and II-II′ of FIG. 8 is shown in FIG. 7 .", "With reference to FIG. 7 and FIG. 8 , the embodiment shown herein is similar to the embodiment shown in FIG. 6 , so that identical components in these figures will be denoted by the same numerals and will not be reiterated herein.", "In this embodiment, the contact opening C 1 is located between the gate G and the second electrode E 2 .", "The gate G and the second electrode E 2 both belong to the second conductive layer M 2 ;", "therefore, when the contact opening C 1 is defined, the contact opening C 1 need be located at a region where the gate G and the second electrode E 2 are not located, so as to prevent the subsequent short circuit between the gate G and the second electrode E 2 .", "Besides, in the present embodiment, the contact opening C 2 is located above the contact opening C 1 .", "However, the contact opening C 2 is not necessarily located right above the contact opening C 1 in the invention.", "[0041] In light of the foregoing, the capacitor described herein is constituted by the first electrode, the second electrode, and the third electrode, and the first electrode is located below the first insulation layer that is below the second electrode.", "Hence, in the invention, the storage capacitance of the capacitor can be increased without negatively affecting the aperture ratio of the pixel structure.", "From another aspect, since none of the first, second, and third electrodes of the capacitor are configured below the data line, the capacitor described herein does not lead to an increase in the loading of the pixel structure.", "Moreover, the light shielding portion disposed below the gate may shield the light from the underside of the substrate, so as to prevent the TFT from generating photo-leakage current.", "[0042] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the invention without departing from the scope or spirit of the invention.", "In view of the foregoing, it is intended that the invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents." ]
FIELD OF THE INVENTION [0001] This invention relates generally to radiation therapy and radiology, and more particularly to a method for reconstructing incomplete patient data for radiation therapy set-up and treatment verification. BACKGROUND OF THE INVENTION [0002] Medical equipment for radiation therapy treats tumorous tissue with high energy radiation. The amount of radiation and its placement must be accurately controlled to ensure both that the tumor receives sufficient radiation to be destroyed, and that the damage to the surrounding and adjacent non-tumorous tissue is minimized. [0003] In external source radiation therapy, a radiation source external to the patient treats internal tumors. The external source is normally collimated to direct a beam only to the tumorous site. The source of high energy radiation may be x-rays, or electrons from linear accelerators in the range of 2-25 MeV, or gamma rays from highly focused radioisotopes such as a Co.sup.60 source having an energy of 1.25 MeV. [0004] One form of external radiation therapy uses the precision of a computed tomography (CT) scanner to irradiate cancerous tissue because it acquires CT scans (e.g. mega-voltage CT or kilo-voltage CT) immediately before, immediately after, or during radiation delivery, with the patient on a treatment apparatus and in the treatment position. This therapy technique uses intensity modulated beams that enter the patient's body at a greater number of angles and positions than conventional therapies, thereby lessening the amount of radiation that healthy tissues are subjected to and concentrating the radiation where it is needed most, at the cancer site(s). Essentially, the radiation field is “sculpted” to match the shape of the cancerous tissue to keep the dose of radiation to healthy tissue near the cancer low. [0005] A radiation treatment plan may be based on a computed tomography (“CT”) image of the patient. As is known in the art, a CT image is produced by a mathematical reconstruction of many projection images obtained at different angles about the patient. In a typical CT scan, the projections are one-dimensional line images indicating the attenuation of the beam by a “slice” of the patient. The actual CT data is held in a matrix wherein each row represents an angle and each column represents a distance. The matrix of data obtained in a CT scan can be displayed as a sinogram as shown in FIG. 1, or reconstructed into a two-dimensional image, as shown in FIG. 2. [0006] In some radiotherapy systems, the oncologist views the cancerous areas on the CT image and determines the beam angles and intensities (identified with respect to the tumor image) which will be used to treat the tumor. In an automated system, such as that disclosed in U.S. Pat. No. 5,661,773, and hereby incorporated by reference, a computer program selects the beam angles and intensities after the physician identifies the tumorous region and upper and lower dose limits for the treatment. [0007] More specifically, the planning images are used to create a 3-D treatment plan of a region of interest. This region of interest is broken down into units called voxels, which are defined as volumetric pixels. Each voxel is then assigned a particular radiation dose depending on what type of tissue or other matter it contains, e.g. cancerous tissue, air, etc. [0008] Normally, the CT image of the patient is acquired substantially before the radiation treatment to allow time for the treatment plan to be prepared. However, the position of organs or other tissue to be treated can change from day-to-day because of a variety of factors. Further, patients move during treatment because of breathing, muscle twitching or the like. Uncertainty in the positioning of the patient with respect to the original CT image can undermine the conformality of the radiation delivery. [0009] Thus, it is highly preferable to verify the treatment plan based on data obtained just prior to the time of treatment. The verification process can be done by techniques that compare the planning image to an image of the patient at the time of treatment. [0010] Unfortunately, the data sets obtained on the day of treatment to be used for preparing the patient model are often incomplete. Patients that are large in size may not fit within the field-of-view (FOV) of the CT machine attached to the therapeutic equipment applying the radiation dose, and may yield an image such as that shown in FIG. 3, which shows only a portion of the image shown in FIG. 1. Not only is there a limited field of view, the data around the edges contains significant artifacts so that the image has an irregular white border and internal values are distorted. Alternatively, only a limited sample size of slices may have been obtained. There may be other limitations that result in the collection of incomplete data sets. [0011] To resolve the problem of limited data sets in which only a portion of an image can be obtained, several scans of the patient may be made at various detector or patient positions, and then combined into a complete set. This has been done by adding together sinogram data, but requires that the imaging apparatus or patient position can be reliably modified accordingly, which is not always possible. Further, the problem of developing artifacts is still present due to the significant degree of mismatch between such data sets, and the additional handling of the patient is more costly, time intensive and can be difficult for frail patients. Moreover, the patients receive a higher dose of radiation with multiple scans than with one single scan. [0012] Reconstruction of incomplete data sets using available techniques results in images that do not show the complete extent of the patient's body, can have artifacts and incorrect voxel values, and thus, limit the extent to which the images can be used for delivery verification, dose reconstruction and patient set-up, deformable patient registration and deformable dose registration. Accordingly, a need exists for a system and method that can solve the problems caused by limited data sets. SUMMARY OF THE INVENTION [0013] The present invention relates to a method by which an incomplete CT patient data set can be combined with an existing CT patient data set to create an image of a patient that is complete and without significant artifacts. [0014] The method includes the steps of obtaining a first sinogram data set from a patient and a second sinogram data set or image from a patient. Both data sets are converted to images, and aligned together so that statistically, there is optimal registration between the two images. The aligned or “fused” image is reprojected as a sinogram. This reprojected sinogram is compared to either the first or second sinogram to determine what data exists beyond the scope of the first or second sinogram. This additional data is added to the sinogram to which the fused sinogram was compared to obtain an augmented sinogram The augmented sinogram is converted to an image, referred to as a fusion-aligned reprojection image. [0015] The method of the present invention is advantageous in that the availability of only one limited data sinogram/image will not affect the ability to perform accurate delivery verification, dose reconstruction, patient set-up or the like. The limited data image or “first image” is fused to a previously taken complete image or “second image.” The sinogram representing the fused image is compared to the limited data sinogram, and the augmented limited data sinogram is prepared therefrom. From the augmented limited data sinogram the fusion-aligned reprojected (FAR) image is obtained. The FAR image is used to accurately apply radiation to the treatment area, which may be positioned differently than as shown in the previously obtained complete image. [0016] The advantages of obtaining current data at the time of treatment or even dosage verification are many. Damage to healthy tissue will be reduced, and the cancerous or diseased tissue will be more accurately targeted. These differences are especially critical in areas that have frequent internal anatomy changes, such as the torso or prostate. [0017] While the present invention is particularly useful in the medical field, other applications are possible and references to use in cancer therapy should not be deemed to limit the application of the present invention. The present invention may be advantageously adapted for use where similar performance capabilities and characteristics are desired. These and other objects and advantages of the present invention will become apparent from the detailed description, claims, and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0018] [0018]FIG. 1 an example of a sinogram obtained from the CT scan of a patient; [0019] [0019]FIG. 2 is an example of a planning CT image obtained from a CT-scan sinogram similar to that shown in FIG. 1; [0020] [0020]FIG. 3 is an example CT image with a limited field of view; [0021] [0021]FIG. 4 is a flowchart showing the process steps of the present invention. [0022] [0022]FIG. 5 is a schematic example of a patient CT scan; [0023] [0023]FIG. 6 is a limited schematic view of FIG. 6, showing the limited scan portion in the center of the object, and the remaining nonscanned portion in phantom; [0024] [0024]FIG. 7 demonstrates how the limited image of FIG. 6 is aligned with the full image of FIG. 5 through the process of fusion; [0025] [0025]FIG. 7A show the actual alignment or “fusion” of the images from FIGS. 5 and 6; [0026] [0026]FIG. 8 is a schematic view of a fusion aligned reprojection image; [0027] [0027]FIG. 9 is a schematic view of a full image corresponding to that in FIG. 6; [0028] [0028]FIG. 10 is a reconstructed image of FIGS. 2 and 3 fused and aligned in accordance with the method of the present invention. DETAILED DESCRIPTION [0029] A preferred method in accordance with the present invention is shown in the flowchart of FIG. 4. A limited data sinogram 50 representing the treatment area is obtained from a patient. In one preferred embodiment of the present invention, the limited data sinogram 50 is prepared near the time that the patient is receiving his or her radiation treatment. However, the limited data sinogram 50 may be obtained at any time. [0030] The limited data sinogram 50 is reconstructed to a limited data image 52 , as seen in the example of FIG. 3, and represented schematically in FIG. 6 as limited object 156 . FIG. 3 contains a significant amount of artifacts such as the white irregular border 53 , and some distortion of image values. By way of example, the treatment area targeted in FIG. 3 is a prostate gland. The method can be applied to images of any part of the body, or be used in veterinary or radiological applications. [0031] A complete image 54 of the same patient and same treatment area is seen in FIG. 2, and represented schematically in FIG. 5 as object 154 . Typically, this complete image 54 will have been made prior to obtaining the limited data image 52 for the purpose of treatment planning. Even if limited image 52 were taken only minutes after the complete data image 54 , there are almost always inherent differences between the location of certain organs or tissue due to patient motion or other bodily functions. If enough time has elapsed between images, weight loss or growth of certain tissue can occur. [0032] It is noted that complete image 54 or limited image 52 need not be from CT scans, and that this technique can be generally applied to matching images from different projection imaging modalities such as magnetic resonance imaging, positron emission tomography, and single photon emission tomography. Thus, there may be misalignment or disagreement between the two images because of differing methods of data collection. [0033] The two images shown in FIGS. 2 and 3 and represented schematically by objects 154 and 156 , in FIGS. 5 and 6 have differences between them. In the actual image example of FIGS. 2 and 3, intestinal gas is shown in FIG. 3, thereby displacing the treatment target. In the schematic example, object 154 is composed of diagonals 158 a and 160 a and an inclusion 161 a , within a frame 162 a . Limited object 156 shows only corresponding diagonals 160 b and 158 b , and part of the inclusion designated as 161 b . Thus, there is a change between diagonal 158 a and 158 b and only partial data for inclusion 161 b. [0034] Referring to FIG. 7, “fusion” or image registration techniques are used to align limited data image 52 with complete image 54 . In the schematic example, limited object 156 is fused with complete object 154 so that statistically, there is optimal registration between the objects 154 and 156 . FIG. 7 shows how the orientation of object 154 is aligned to closely match that of object 156 . FIG. 7A shows diagonal 160 c as the perfect registration between diagonals 160 a and 160 b . There is less than perfect registration between diagonals 158 a and 158 b . Both lines are superimposed only by way of example to show that fusion is not perfect as evidenced by the double edge 163 . [0035] Image registration or fusion may be achieved by several techniques. One such technique is known as mutual information (MI), for which a well-known algorithm has been developed. One such example of this algorithm being used to register multi-modal images is described in the following publication, incorporated herein by reference: Frederik Maes, Andre Collignon, Dirk Vendermeulen, Guy Marchal, and Paul Suetens, Multimodality Image Registration by Maximization of Mutual Information , Vol. 16, No. 2, IEEE Transactions on Medical Imaging, 187 (April 1997). [0036] Extracted Feature Fusion (EFF) is another registration technique providing numerous advantages over prior art techniques. EFF is a voxel-based image registration method, wherein only extracted features of images are registered or fused. For example, a patient's bone structure usually stays the same even when a patient loses a substantial amount of weight. Therefore, the bones can in effect be extracted from each image subject to alignment, and then registered using statistical methods. In the simple example of FIG. 5, diagonal 160 a and frame 162 may represent bone or tissue that remains relatively unchanged over time. Therefore, only these relatively static features might be selected for fusion, while other features that are more dynamic, perhaps diagonals 158 a,b and inclusion 161 a,b, need not be included in the registration calculations. [0037] The benefits of registering only an extracted portion of an image are reduced calculation times, improved accuracy, and more clearly defined goals for alignment in cases where the patient has significantly changed in shape. The benefits arise from the registration of fewer data points, which in this case are voxels. The total processing time is generally proportional to the number of points selected, so reducing that number from the size of the entire three-dimensional image set to a subset of points meeting certain criteria (e.g. voxels that represent bone or do not represent air) will typically reduce calculation times. This reduction of voxels can provide more accurate results than other methods of reducing the number of voxels for MI techniques, such as regular down-sampling. [0038] Other image registration techniques include manual fusion, alignment using geometric features (e.g. surfaces), gradient methods, and voxel-similarity techniques. [0039] Referring back to FIG. 4, the aligned or transformed complete image 56 is reprojected as a sinogram 58 . The data for sinogram 58 is once again in a matrix wherein each row represents an angle, and each column represents distance. The data matrix of the reprojected sinogram is compared to the data matrix for limited data sinogram 50 to determine what data is missing from the limited sinogram. This is now possible because the complete sinogram is in alignment with the limited sinogram. [0040] The approximation of the missing sinogram data from the reprojected, fusion aligned version of image 154 is added to the limited sinogram 50 to create an augmented limited data sinogram, or augmented sinogram 60 . The augmented sinogram 60 is reconstructed to a fusion aligned reprojection image (FAR image) 62 that is an approximation of what the complete image would have looked like at the time the limited data image was obtained. The FAR image 62 is represented schematically in FIG. 8. Frame 162 is the same as in FIG. 5, and diagonals 158 c , 160 c and inclusion 161 c are now complete. This can compared to the object 168 in FIG. 9, which represents the image that would have been taken at the time of treatment if it were possible to obtain a complete image. The fact that the outer regions 170 of diagonal 158 d are not the same as diagonal 158 c is not critical to the invention. FIG. 10 represents a reconstructed image obtained by combining FIGS. 2 and 3 in accordance with the method of the present invention. It can be seen that slight artifacts such as the faint ring 180 can result. However, such artifacts are insignificant because they do not impair the conspicuity of the important structures in the field of view, nor do they noticeably detriment dose calculations or other processes that utilize these images. [0041] The reconstructed image obtained from method of the present invention can then be used for patient setup (positioning the patient prior to delivery), dose registration (changing delivery patterns to compensate for patient position or tumor shape changes), delivery verification (using a signal measured at an exit detector to compute energy fluence directed toward a patient), deformable patient registration and deformable dose registration (using anatomical, biomechanical and region of interest data to map changes in the patient's anatomy between each fraction, a reconstructed dose is mapped to a reference image to obtain a cumulative dose). [0042] It will be understood to those of ordinary skill in the art that other methods of comparing images may be used including, for example, those which would recognize changes beyond rigid body translation or rotation. [0043] Although the invention has been herein shown and described in what is perceived to be the most practical and preferred embodiments, it is to be understood that the invention is not intended to be limited to the specific embodiments set forth above. It is recognized that modifications may be made by one of skill in the art of the invention without departing from the spirit or intent of the invention and therefore, the invention is to be taken as including all reasonable equivalents to the subject matter of the appended claims.
The present invention provides a system and method of using current but incomplete data to prepare an approximated complete image of a patient potentially undergoing radiation therapy. A limited patient image, such as that obtained from a CT scan is fused with a complete image of the same area using image registration techniques. The fused image is converted to sinogram data. This data is compared to sinogram data corresponding to the limited patient image to determine what data exists beyond the scope of the limited sinogram. Any additional data is added to the limited data sinogram to obtain a complete sinogram. This is reconstructed into an image that approximates the complete image that would have been taken at the time the limited image was obtained.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "FIELD OF THE INVENTION [0001] This invention relates generally to radiation therapy and radiology, and more particularly to a method for reconstructing incomplete patient data for radiation therapy set-up and treatment verification.", "BACKGROUND OF THE INVENTION [0002] Medical equipment for radiation therapy treats tumorous tissue with high energy radiation.", "The amount of radiation and its placement must be accurately controlled to ensure both that the tumor receives sufficient radiation to be destroyed, and that the damage to the surrounding and adjacent non-tumorous tissue is minimized.", "[0003] In external source radiation therapy, a radiation source external to the patient treats internal tumors.", "The external source is normally collimated to direct a beam only to the tumorous site.", "The source of high energy radiation may be x-rays, or electrons from linear accelerators in the range of 2-25 MeV, or gamma rays from highly focused radioisotopes such as a Co.sup[.", "].60 source having an energy of 1.25 MeV.", "[0004] One form of external radiation therapy uses the precision of a computed tomography (CT) scanner to irradiate cancerous tissue because it acquires CT scans (e.g. mega-voltage CT or kilo-voltage CT) immediately before, immediately after, or during radiation delivery, with the patient on a treatment apparatus and in the treatment position.", "This therapy technique uses intensity modulated beams that enter the patient's body at a greater number of angles and positions than conventional therapies, thereby lessening the amount of radiation that healthy tissues are subjected to and concentrating the radiation where it is needed most, at the cancer site(s).", "Essentially, the radiation field is “sculpted”", "to match the shape of the cancerous tissue to keep the dose of radiation to healthy tissue near the cancer low.", "[0005] A radiation treatment plan may be based on a computed tomography (“CT”) image of the patient.", "As is known in the art, a CT image is produced by a mathematical reconstruction of many projection images obtained at different angles about the patient.", "In a typical CT scan, the projections are one-dimensional line images indicating the attenuation of the beam by a “slice”", "of the patient.", "The actual CT data is held in a matrix wherein each row represents an angle and each column represents a distance.", "The matrix of data obtained in a CT scan can be displayed as a sinogram as shown in FIG. 1, or reconstructed into a two-dimensional image, as shown in FIG. 2. [0006] In some radiotherapy systems, the oncologist views the cancerous areas on the CT image and determines the beam angles and intensities (identified with respect to the tumor image) which will be used to treat the tumor.", "In an automated system, such as that disclosed in U.S. Pat. No. 5,661,773, and hereby incorporated by reference, a computer program selects the beam angles and intensities after the physician identifies the tumorous region and upper and lower dose limits for the treatment.", "[0007] More specifically, the planning images are used to create a 3-D treatment plan of a region of interest.", "This region of interest is broken down into units called voxels, which are defined as volumetric pixels.", "Each voxel is then assigned a particular radiation dose depending on what type of tissue or other matter it contains, e.g. cancerous tissue, air, etc.", "[0008] Normally, the CT image of the patient is acquired substantially before the radiation treatment to allow time for the treatment plan to be prepared.", "However, the position of organs or other tissue to be treated can change from day-to-day because of a variety of factors.", "Further, patients move during treatment because of breathing, muscle twitching or the like.", "Uncertainty in the positioning of the patient with respect to the original CT image can undermine the conformality of the radiation delivery.", "[0009] Thus, it is highly preferable to verify the treatment plan based on data obtained just prior to the time of treatment.", "The verification process can be done by techniques that compare the planning image to an image of the patient at the time of treatment.", "[0010] Unfortunately, the data sets obtained on the day of treatment to be used for preparing the patient model are often incomplete.", "Patients that are large in size may not fit within the field-of-view (FOV) of the CT machine attached to the therapeutic equipment applying the radiation dose, and may yield an image such as that shown in FIG. 3, which shows only a portion of the image shown in FIG. 1. Not only is there a limited field of view, the data around the edges contains significant artifacts so that the image has an irregular white border and internal values are distorted.", "Alternatively, only a limited sample size of slices may have been obtained.", "There may be other limitations that result in the collection of incomplete data sets.", "[0011] To resolve the problem of limited data sets in which only a portion of an image can be obtained, several scans of the patient may be made at various detector or patient positions, and then combined into a complete set.", "This has been done by adding together sinogram data, but requires that the imaging apparatus or patient position can be reliably modified accordingly, which is not always possible.", "Further, the problem of developing artifacts is still present due to the significant degree of mismatch between such data sets, and the additional handling of the patient is more costly, time intensive and can be difficult for frail patients.", "Moreover, the patients receive a higher dose of radiation with multiple scans than with one single scan.", "[0012] Reconstruction of incomplete data sets using available techniques results in images that do not show the complete extent of the patient's body, can have artifacts and incorrect voxel values, and thus, limit the extent to which the images can be used for delivery verification, dose reconstruction and patient set-up, deformable patient registration and deformable dose registration.", "Accordingly, a need exists for a system and method that can solve the problems caused by limited data sets.", "SUMMARY OF THE INVENTION [0013] The present invention relates to a method by which an incomplete CT patient data set can be combined with an existing CT patient data set to create an image of a patient that is complete and without significant artifacts.", "[0014] The method includes the steps of obtaining a first sinogram data set from a patient and a second sinogram data set or image from a patient.", "Both data sets are converted to images, and aligned together so that statistically, there is optimal registration between the two images.", "The aligned or “fused”", "image is reprojected as a sinogram.", "This reprojected sinogram is compared to either the first or second sinogram to determine what data exists beyond the scope of the first or second sinogram.", "This additional data is added to the sinogram to which the fused sinogram was compared to obtain an augmented sinogram The augmented sinogram is converted to an image, referred to as a fusion-aligned reprojection image.", "[0015] The method of the present invention is advantageous in that the availability of only one limited data sinogram/image will not affect the ability to perform accurate delivery verification, dose reconstruction, patient set-up or the like.", "The limited data image or “first image”", "is fused to a previously taken complete image or “second image.”", "The sinogram representing the fused image is compared to the limited data sinogram, and the augmented limited data sinogram is prepared therefrom.", "From the augmented limited data sinogram the fusion-aligned reprojected (FAR) image is obtained.", "The FAR image is used to accurately apply radiation to the treatment area, which may be positioned differently than as shown in the previously obtained complete image.", "[0016] The advantages of obtaining current data at the time of treatment or even dosage verification are many.", "Damage to healthy tissue will be reduced, and the cancerous or diseased tissue will be more accurately targeted.", "These differences are especially critical in areas that have frequent internal anatomy changes, such as the torso or prostate.", "[0017] While the present invention is particularly useful in the medical field, other applications are possible and references to use in cancer therapy should not be deemed to limit the application of the present invention.", "The present invention may be advantageously adapted for use where similar performance capabilities and characteristics are desired.", "These and other objects and advantages of the present invention will become apparent from the detailed description, claims, and accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS [0018] [0018 ]FIG. 1 an example of a sinogram obtained from the CT scan of a patient;", "[0019] [0019 ]FIG. 2 is an example of a planning CT image obtained from a CT-scan sinogram similar to that shown in FIG. 1;", "[0020] [0020 ]FIG. 3 is an example CT image with a limited field of view;", "[0021] [0021 ]FIG. 4 is a flowchart showing the process steps of the present invention.", "[0022] [0022 ]FIG. 5 is a schematic example of a patient CT scan;", "[0023] [0023 ]FIG. 6 is a limited schematic view of FIG. 6, showing the limited scan portion in the center of the object, and the remaining nonscanned portion in phantom;", "[0024] [0024 ]FIG. 7 demonstrates how the limited image of FIG. 6 is aligned with the full image of FIG. 5 through the process of fusion;", "[0025] [0025 ]FIG. 7A show the actual alignment or “fusion”", "of the images from FIGS. 5 and 6;", "[0026] [0026 ]FIG. 8 is a schematic view of a fusion aligned reprojection image;", "[0027] [0027 ]FIG. 9 is a schematic view of a full image corresponding to that in FIG. 6;", "[0028] [0028 ]FIG. 10 is a reconstructed image of FIGS. 2 and 3 fused and aligned in accordance with the method of the present invention.", "DETAILED DESCRIPTION [0029] A preferred method in accordance with the present invention is shown in the flowchart of FIG. 4. A limited data sinogram 50 representing the treatment area is obtained from a patient.", "In one preferred embodiment of the present invention, the limited data sinogram 50 is prepared near the time that the patient is receiving his or her radiation treatment.", "However, the limited data sinogram 50 may be obtained at any time.", "[0030] The limited data sinogram 50 is reconstructed to a limited data image 52 , as seen in the example of FIG. 3, and represented schematically in FIG. 6 as limited object 156 .", "FIG. 3 contains a significant amount of artifacts such as the white irregular border 53 , and some distortion of image values.", "By way of example, the treatment area targeted in FIG. 3 is a prostate gland.", "The method can be applied to images of any part of the body, or be used in veterinary or radiological applications.", "[0031] A complete image 54 of the same patient and same treatment area is seen in FIG. 2, and represented schematically in FIG. 5 as object 154 .", "Typically, this complete image 54 will have been made prior to obtaining the limited data image 52 for the purpose of treatment planning.", "Even if limited image 52 were taken only minutes after the complete data image 54 , there are almost always inherent differences between the location of certain organs or tissue due to patient motion or other bodily functions.", "If enough time has elapsed between images, weight loss or growth of certain tissue can occur.", "[0032] It is noted that complete image 54 or limited image 52 need not be from CT scans, and that this technique can be generally applied to matching images from different projection imaging modalities such as magnetic resonance imaging, positron emission tomography, and single photon emission tomography.", "Thus, there may be misalignment or disagreement between the two images because of differing methods of data collection.", "[0033] The two images shown in FIGS. 2 and 3 and represented schematically by objects 154 and 156 , in FIGS. 5 and 6 have differences between them.", "In the actual image example of FIGS. 2 and 3, intestinal gas is shown in FIG. 3, thereby displacing the treatment target.", "In the schematic example, object 154 is composed of diagonals 158 a and 160 a and an inclusion 161 a , within a frame 162 a .", "Limited object 156 shows only corresponding diagonals 160 b and 158 b , and part of the inclusion designated as 161 b .", "Thus, there is a change between diagonal 158 a and 158 b and only partial data for inclusion 161 b. [0034] Referring to FIG. 7, “fusion”", "or image registration techniques are used to align limited data image 52 with complete image 54 .", "In the schematic example, limited object 156 is fused with complete object 154 so that statistically, there is optimal registration between the objects 154 and 156 .", "FIG. 7 shows how the orientation of object 154 is aligned to closely match that of object 156 .", "FIG. 7A shows diagonal 160 c as the perfect registration between diagonals 160 a and 160 b .", "There is less than perfect registration between diagonals 158 a and 158 b .", "Both lines are superimposed only by way of example to show that fusion is not perfect as evidenced by the double edge 163 .", "[0035] Image registration or fusion may be achieved by several techniques.", "One such technique is known as mutual information (MI), for which a well-known algorithm has been developed.", "One such example of this algorithm being used to register multi-modal images is described in the following publication, incorporated herein by reference: Frederik Maes, Andre Collignon, Dirk Vendermeulen, Guy Marchal, and Paul Suetens, Multimodality Image Registration by Maximization of Mutual Information , Vol. 16, No. 2, IEEE Transactions on Medical Imaging, 187 (April 1997).", "[0036] Extracted Feature Fusion (EFF) is another registration technique providing numerous advantages over prior art techniques.", "EFF is a voxel-based image registration method, wherein only extracted features of images are registered or fused.", "For example, a patient's bone structure usually stays the same even when a patient loses a substantial amount of weight.", "Therefore, the bones can in effect be extracted from each image subject to alignment, and then registered using statistical methods.", "In the simple example of FIG. 5, diagonal 160 a and frame 162 may represent bone or tissue that remains relatively unchanged over time.", "Therefore, only these relatively static features might be selected for fusion, while other features that are more dynamic, perhaps diagonals 158 a,b and inclusion 161 a,b, need not be included in the registration calculations.", "[0037] The benefits of registering only an extracted portion of an image are reduced calculation times, improved accuracy, and more clearly defined goals for alignment in cases where the patient has significantly changed in shape.", "The benefits arise from the registration of fewer data points, which in this case are voxels.", "The total processing time is generally proportional to the number of points selected, so reducing that number from the size of the entire three-dimensional image set to a subset of points meeting certain criteria (e.g. voxels that represent bone or do not represent air) will typically reduce calculation times.", "This reduction of voxels can provide more accurate results than other methods of reducing the number of voxels for MI techniques, such as regular down-sampling.", "[0038] Other image registration techniques include manual fusion, alignment using geometric features (e.g. surfaces), gradient methods, and voxel-similarity techniques.", "[0039] Referring back to FIG. 4, the aligned or transformed complete image 56 is reprojected as a sinogram 58 .", "The data for sinogram 58 is once again in a matrix wherein each row represents an angle, and each column represents distance.", "The data matrix of the reprojected sinogram is compared to the data matrix for limited data sinogram 50 to determine what data is missing from the limited sinogram.", "This is now possible because the complete sinogram is in alignment with the limited sinogram.", "[0040] The approximation of the missing sinogram data from the reprojected, fusion aligned version of image 154 is added to the limited sinogram 50 to create an augmented limited data sinogram, or augmented sinogram 60 .", "The augmented sinogram 60 is reconstructed to a fusion aligned reprojection image (FAR image) 62 that is an approximation of what the complete image would have looked like at the time the limited data image was obtained.", "The FAR image 62 is represented schematically in FIG. 8. Frame 162 is the same as in FIG. 5, and diagonals 158 c , 160 c and inclusion 161 c are now complete.", "This can compared to the object 168 in FIG. 9, which represents the image that would have been taken at the time of treatment if it were possible to obtain a complete image.", "The fact that the outer regions 170 of diagonal 158 d are not the same as diagonal 158 c is not critical to the invention.", "FIG. 10 represents a reconstructed image obtained by combining FIGS. 2 and 3 in accordance with the method of the present invention.", "It can be seen that slight artifacts such as the faint ring 180 can result.", "However, such artifacts are insignificant because they do not impair the conspicuity of the important structures in the field of view, nor do they noticeably detriment dose calculations or other processes that utilize these images.", "[0041] The reconstructed image obtained from method of the present invention can then be used for patient setup (positioning the patient prior to delivery), dose registration (changing delivery patterns to compensate for patient position or tumor shape changes), delivery verification (using a signal measured at an exit detector to compute energy fluence directed toward a patient), deformable patient registration and deformable dose registration (using anatomical, biomechanical and region of interest data to map changes in the patient's anatomy between each fraction, a reconstructed dose is mapped to a reference image to obtain a cumulative dose).", "[0042] It will be understood to those of ordinary skill in the art that other methods of comparing images may be used including, for example, those which would recognize changes beyond rigid body translation or rotation.", "[0043] Although the invention has been herein shown and described in what is perceived to be the most practical and preferred embodiments, it is to be understood that the invention is not intended to be limited to the specific embodiments set forth above.", "It is recognized that modifications may be made by one of skill in the art of the invention without departing from the spirit or intent of the invention and therefore, the invention is to be taken as including all reasonable equivalents to the subject matter of the appended claims." ]
TECHNICAL FIELD The present disclosure relates generally to an electrostatographic or xerographic printing machine, and more particularly concerns a development subsystem that uses semiconductive developer on a photoreceptor. BACKGROUND In the process of electrophotographic printing, a charge-retentive surface, also known as a photoreceptor, is charged to a substantially uniform potential, so as to sensitize the surface of the photoreceptor. The charged portion of the photoreceptor is exposed to a light image of an original document being reproduced, or else a scanned laser image created by the action of digital image data acting on a laser source. The scanning or exposing step records an electrostatic latent image on the photoreceptor corresponding to the informational areas in the document to be printed or copied. After the electrostatic latent image is recorded on the photoreceptor, the electrostatic latent image is developed by causing toner particles to adhere electrostatically to the charged areas forming the electrostatic latent image. This developed toner image on the photoreceptor is subsequently transferred to a sheet on which the desired image is to be printed. Finally, the toner on the sheet is heated to permanently fuse the toner image to the sheet. One familiar type of development of an electrostatic latent image is called “two-component development”. Two-component developer material largely comprises toner particles interspersed with carrier particles. The carrier particles are magnetically attractable, and the toner particles are caused to adhere triboelectrically to the carrier particles. This two-component developer can be conveyed, by means such as a “magnetic roll,” to the electrostatic latent image, where toner particles become detached from the carrier particles and adhere to the electrostatic latent image. In magnetic roll development systems, the carrier particles with the triboelectrically adhered toner particles are transported by the magnetic rolls through a development zone. The development zone is the area between the outside surface of a magnetic roll and the photoreceptor on which an electrostatic latent image has been formed. Because the carrier particles are attracted to the magnetic roll, some of the toner particles are interposed between a carrier particle and the electrostatic latent image on the photoreceptor. These toner particles are attracted to the electrostatic latent image and transfer from the carrier particles to the electrostatic latent image. The carrier particles are removed from the development zone as they continue to follow the rotating surface of the magnetic roll. The carrier particles then fall from the magnetic roll and return to the developer supply where they attract more toner particles and are reused in the development process. The carrier particles fall from the magnetic roll under the effects of gravity or are directed away from the roller surface by a magnetic field. Different types of carrier particles have been used in efforts to improve the development of toner from two-component developer with magnetic roll development systems. One type of carrier particle is a very electrically insulated carrier and development systems using developer having these carrier particles typically develop lines and fine detail with high fidelity. Development efficiency for solid areas, however, is increased through low magnetic field agitation in the development zone along with close spacing to the electrostatic latent image and elongation of the development zone. The magnetic field agitation helps prevent electric field collapse caused by toner countercharge in the development zone. The close spacing increases the effective electric field for a potential difference and the longer development zone provides more time for toner development. A disadvantage of this type of development system is the tendency for the carrier beads to retain countercharge left by toner particles that were developed from the brush. Retention of the countercharge causes carrier beads to be lost to the photoreceptor background areas. This loss is undesirable and leads to contamination problems in the xerographic system as well as depletion of the developer sump over time. Other two-component developers have used permanently magnetized carrier particles because these carrier particles dissipate toner countercharge more quickly by enabling a very dynamic mixing region to form on the magnetic roll. Another type of carrier particle used in two-component developers is an electrically conductive carrier particle. Developers using this type of carrier particle are capable of being used in magnetic roll systems that produce toner bearing substrates at speeds of up to approximately 100 pages per minute (ppm). These developers typically recruit toner for the electrostatic latent image from areas near the tip of the developer magnetic brush that are proximate the surface of the photoreceptor because the electric fields are high in this region. The electrical conductivity of the carrier particles serves to prevent development field collapse caused by the retention of toner countercharge and thereby allows high efficiency development, especially of solid area latent images. This type of developer, however, supplies an adequate amount of toner for high speed xerography with difficulty because the only toner available for development is the toner near the tip of the magnetic brush. Consequently, high development roller speeds are required. Unfortunately, high roller speeds increase the wear on the rollers and decrease the life of the rollers. Another problem that occurs with this type of developer is the tendency of the carrier particles, when the toner concentrations are low, to charge up in the image electric field. This charge causes the carrier particles to develop onto the image areas of the photoreceptor and leads to white spot deletions in the final image as well as carrier bead contamination in the system. Another type of carrier particle used in two-component developers is the semiconductive carrier particle. Developers using this type of carrier particle are also capable of being used in magnetic roll systems that produce toner bearing substrates at speeds of up to approximately 100 pages per minute (ppm). Developers having semiconductive carrier particles use a relatively thin layer of developer on the magnetic roll in the development zone. This feature allows more of the toner to be recruited during development than thick brush conductive developers allow. In these systems an AC electric waveform is applied to the magnetic roller to cause the developer to become electrically conductive during the development process. The electrically conductive developer increases the efficiency of development by preventing development field collapse due to countercharge left in the magnetic brush by the developed toner. A typical waveform applied to these systems is, for example, a square wave at a peak to peak amplitude of 1000 Volts and a frequency of 9 KHz. This waveform controls both the toner movement and the electric fields in the development zone. Typically these systems run in a “with” mode, which means the magnetic roll surface runs in the same direction as the photoreceptor. This movement in the same direction tends to keep background development low, but it has been observed to produce inadequate development unless high magnetic roll surface speeds are used to get an adequate supply of toner into the development zone. This high magnetic roll surface speed requires high strength magnets to control the developer bed. These types of magnets are expensive. Additionally, high speeds also increase the wear on bearings in the developer housing. Another limitation of known magnetic roll systems used with developers having semiconductive carrier particles is the difficulty in extending the development zone to increase the time in which toner development may occur. One method for increasing development zone length with other developers having insulated or conductive carrier particles is to use two magnetic rolls. The two rolls are placed close together with their centers aligned to form a line that is parallel to the photoreceptor. Because the developer layer for semiconductive carrier particle developer is so thin, magnetic fields sufficiently strong enough to cause semiconductive carrier particles to migrate in adequate quantities from one magnetic roll to the other magnetic roll also interfere with the transfer of toner from the carrier particles in the development zones. Consequently, construction of the magnetic rolls requires careful consideration of this interference. If two rolls are not able to be used to increase the development zone, then the radius of the magnetic roll may be increased to accommodate this goal. There is a limit, however, to the diameter of the magnetic roll. One limit is simply the area within the printing machine that is available for a development subsystem. Another limit is the size and strength of the magnets internal to the magnetic roll that are required to provide adequate magnetic field strengths and shapes at the surface of a larger magnetic roll. Another problem with semiconductive development systems is a defect in which the system has trouble developing a halftone adjacent and following a solid so a halo of the solid is left at the boundary of the halftone. This happens at high toner concentrations and limits the latitude of the system. The systems and methods discussed below address the limitations of development subsystems using developer having semiconductive carrier particles that have been noted. SUMMARY A development subsystem is used to develop toner having semiconductive carrier particles and toner particles. The development subsystem increases the time for developing the toner and provides an adequate supply of developer for good line detail, edges, and solids. The subsystem includes a developer housing, for retaining a quantity of developer having semiconductive carrier particles and toner particles, a first magnetic roll having a stationary core with at least one magnet and a sleeve that rotates about the stationary core of the first magnetic roll, a second magnetic roll having a stationary core with at least one magnet and a sleeve that rotates about the stationary core of the second magnetic roll, and a motor coupled to the first and the second magnetic rolls to drive the rotating sleeves of the first and the second magnetic rolls in a direction that is against the direction of a photoreceptor that rotates in proximity to the first and the second magnetic rolls. The first and the second magnetic rolls carry semiconductive carrier particles and toner particles through a development zone formed by the first and the second magnetic rolls. A method for developing developer having semiconductive carrier particles in an electrostatographic printing machine includes retaining a quantity of developer having semiconductive carrier particles and toner particles, transporting the developer through a development zone for development on a photoreceptor in a direction that is against the direction of the photoreceptor rotating through the development zone. The transportation of the developer in this method may be implemented by rotating a first sleeve about a first stationary core having at least one magnet, rotating a second sleeve about a second stationary core having at least one magnet, and the rotation of the first and the second sleeves occurs in a direction that is against the direction of the photoreceptor. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of an electrostatographic printing apparatus incorporating a semiconductive magnetic brush development (SCMB) system having two magnetic rolls. FIG. 2 is a sectional view of a SCMB developer unit having two magnetic rolls. FIG. 3 is a perspective view of a SCMB developer unit having two magnetic rolls. FIG. 4 is a perspective view of a SCMB developer unit showing the relationship of the two magnetic rolls to the path of the photoreceptor bearing a latent image. FIG. 5 is a perspective view of a magnetic roll used in the developer system shown in FIG. 2 . DETAILED DESCRIPTION FIG. 1 is an elevational view of an electrostatographic printing apparatus 10 , such as a printing machine, printer or copier, having a development subsystem that uses two magnetic rolls for developing toner particles that are carried on semiconductive carrier particles. The machine 10 includes a feeder unit 14 , a printing unit 18 , and an output unit 20 . The feeder unit 14 houses supplies of media sheets and substrates onto which document images are transferred by the printing unit 18 . Sheets to which images have been fixed are delivered to the output unit 20 for correlating and/or stacking in trays for pickup. The printing unit 18 includes an operator console 24 where job tickets may be reviewed and/or modified for print jobs performed by the machine 10 . The pages to be printed during a print job may be scanned by the machine 10 or received over an electrical communication link. The page images are used to generate bit data that are provided to a raster output scanner (ROS) 30 for forming a latent image on a photoreceptor 28 . Photoreceptor 28 continuously travels the circuit depicted in the figure in the direction indicated by the arrow. A development subsystem 26 develops toner on the photoreceptor 28 . At a transfer station 38 , the toner conforming to the latent image is transferred to the substrate by electric fields generated by the transfer station 38 . The substrate bearing the toner image travels to a fuser station 44 where the toner image is fixed to the substrate. The substrate is then carried to the output unit 20 . This description is provided to generally describe the environment in which a double magnetic roll development system for developer having semiconductive carrier particles may be used and is not intended to limit the use of such a development subsystem 26 to this particular printing machine environment. The overall function of a developer unit 100 , which is shown in FIG. 2 , is to apply marking material, such as toner, onto suitably-charged areas forming a latent image on an image receptor such as the photoreceptor 28 , in a manner generally known in the art. The developer unit 100 , however, provides a longer development zone while maintaining an adequate supply of developer having semiconductive carrier particles than development systems previously known. In various types of printers, there may be multiple such developer units 100 , such as one for each primary color or other purpose. Among the elements of the developer unit 100 , which is shown in FIG. 2 , are a housing 12 , which functions generally to hold a supply of developer material having semiconductive carrier particles, as well as augers, such as 30 , 32 , 34 , which variously mix and convey the developer material, and magnetic rolls 36 , 38 , which in this embodiment form magnetic brushes to apply developer material to the photoreceptor 28 . Other types of features for development of latent images, such as donor rolls, paddles, scavengeless-development electrodes, commutators, etc., are known in the art and may be used in conjunction with various embodiments pursuant to the claims. In the illustrated embodiment, there is further provided air manifolds 40 , 42 , attached to vacuum sources (not shown) for removing dirt and excess particles from the transfer zone near photoreceptor 28 . As mentioned above, a two-component developer material is comprised of toner and carrier. The carrier particles in a two-component developer are generally not applied to the photoreceptor 28 , but rather remain circulating within the housing 12 . The augers 30 , 32 , and 34 are configured and cooperate in a manner described in co-pending applications entitled “Variable Pitch Auger To Improve Pickup Latitude In Developer Housing,” U.S. Ser. No. 11/263,370, which was filed on even date herewith, and “Developer Housing Design With Improved Sump Mass Variation Latitude,” U.S. Ser. No. 11/263,371, which was also filed on even date herewith, both of which are hereby expressly incorporated herein in their entireties by reference and are commonly assigned to the assignee of this patent application. FIG. 3 is a perspective view of a portion of developer unit 100 . As can be seen in this embodiment, the upper magnetic roll 36 and the lower magnetic roll 38 form a development zone that is approximately as long as the two diameters of the magnetic rolls 36 and 38 . As further can be seen, a motor 60 is used with a mechanism, generally indicated with reference numeral 62 , to cause rotation of the various augers 30 , 32 , 34 , magnetic rolls 36 and 38 , and any other rotatable members within the developer unit 100 at various relative velocities. There may be provided any number of such motors. The magnetic rolls 36 and 38 are rotated in a direction that is opposite to the direction in which the photoreceptor 28 moves past the developer unit 100 . That is, the two magnetic rolls 36 and 38 are operated in the against mode for development of toner. In one embodiment of the developer unit 100 , the motor 60 and the mechanism 62 cause the magnetic rolls 36 and 38 to rotate at a speed in the range of about 1 to about 1.5 times the rotational speed of the photoreceptor 28 . This rotational speed is lower than the rotational speed of magnetic rolls in developer systems that rotate in the same direction as the photoreceptor 28 . That is, the magnetic rolls operated in the against mode may be rotated at lower speeds than magnetic rolls operated in the with mode. These slower speeds increase the life of the magnetic rolls over the life of magnetic rolls that are operated in the with mode to develop toner carried on semiconductive carrier particles. FIG. 4 shows the relationship of the photoreceptor 28 to the developer unit 100 within a printing machine, such as the machine 10 shown in FIG. 1 . In this arrangement, the lower magnetic roll 38 develops approximately 70% of the toner that is developed in the development zone of the developer unit 100 and the upper magnetic roll 36 develops approximately 30% of the toner. The upper magnetic roll 36 also cleans up the carrier particles from the development zone. The two magnetic roll arrangement operating in the against mode is able to develop toner carried by semiconductive carrier particles while maintaining fine line and edge development at speeds from 100 to over 200 ppm. As is well known, magnetic rolls, such as magnetic rolls 36 and 38 , are comprised of a rotating sleeve and a stationary core in which magnets are housed. In order to provide a surface that impedes the slippage of carrier particles as the outer sleeve rotates, the outer surface of the rotating sleeve may be sand-blasted or grooved. Previously known SCMB systems used sand-blasted stainless steel rollers, but these rollers have relatively short functional life of approximately 2 million prints or copies. Other known magnetic brush systems that use other types of developers used grooved stainless steel rollers having a depth of approximately 200 to 250 microns. The use of these grooved rollers in a double magnetic roller development subsystem operating in the against mode reduced the trim gap for the development subsystem from approximately 0.7 mm to approximately 0.135 mm. The trim gap is the distance between the trim blade and the upper magnetic roll 36 . The trim blade assists in the removal of excess developer from the upper magnetic roll 36 before it is carried into the development zone. A narrow trim gap presents issues with respect to the manufacturing of the developer unit. For one, the tolerances for the components that comprise the trim blade that assists in the removal of carrier particles from the upper magnetic roll are more difficult to meet. More precise manufacturing techniques and higher rejection rates increase the unit manufacturing cost for the trim blade. Additionally, a narrower trim gap requires greater torque from the motor driving the roller and it also increases the aging of the developer. In an embodiment that uses stainless rollers to provide relatively long life for the rollers, for example, 20 million prints, the rollers are made of stainless steel that has been machined with longitudinal grooves that support a trim gap of approximately 0.5 mm to approximately 0.7 mm. To increase the trim gap to this distance, the rotating sleeves were machined with grooves as shown, for example, in FIG. 5 . The grooves 200 are machined across the face of the rotating sleeve 204 . The grooves 200 are approximately 1.2 mm to approximately 1.4 mm apart. The area between the grooves 200 may be sandblasted, however, surfaces that are relatively smooth between the grooves 200 support more acceptable trim gaps. In one embodiment, the surface roughness of sleeve 204 between the grooves is less than about 2.0 Rz. The grooves 200 assist in maintaining the semiconductive carrier particles on the magnetic rolls as they move through the development zone. In one embodiment, the grooves 200 are preferably cut in either a U or a V shape, although other shapes may be used. The U or V-shaped grooves may be formed in one of two manners. In one construction, the sides of the U or the V-shaped grooves may have the same pitch, but the U-shaped grooves are deeper than the V-shaped grooves. In the other construction, the U and V-shaped grooves may have the same depth, but the U-shaped grooves have sides with a pitch that are shallower than the sides of the V-shaped grooves. As shown in the figure, the sides of a groove 200 are oriented at an angle of approximately 90°±10° and pitched to be a length of about 1.2 to about 1.4 mm. The depth of a groove 200 is approximately 90 to 100 microns. These groove parameters may be used with a trim magnet having a pole strength of approximately 400 to 600 gauss. Of course, these parameters may be altered for other roll dimensions or trim magnet pole strengths. A pair of magnetic rolls having the grooves described above was capable of being long life stainless steel sleeves that operated with a trim gap of approximately 0.5 to 0.7 mm, instead of the 0.135 mm gap experienced with the magnetic rolls having rotating sleeves that had grooves of approximately 200 microns to 250 microns. Although the various embodiments described above have been discussed with regard to an arrangement in which the developer is distributed from an upper magnetic roll to a lower magnetic roll, the reverse may also be used in another embodiment. In such an embodiment, the developer having semiconductive carrier particles is picked up by the lower magnetic roll and then transferred from the lower magnetic roll to the upper magnetic roll. At the upper magnetic roll, the semiconductive carrier particles are removed by gravity or the magnetic field generated by one or more magnets in the upper magnetic roll or a combination of gravity and magnetic fields. The removed carrier particles are returned to the developer supply. The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
A development subsystem is used to develop developer having semiconductive carrier particles and toner particles. The development subsystem includes a developer housing, for retaining a quantity of developer having semiconductive carrier particles and toner particles, a first magnetic roll having a stationary core with at least one magnet and a sleeve that rotates about the stationary core of the first magnetic roll, a second magnetic roll having a stationary core with at least one magnet and a sleeve that rotates about the stationary core of the second magnetic roll, and a motor coupled to the first and the second magnetic rolls to drive the rotating sleeves of the first and the second magnetic rolls in a direction that is against the direction of a photoreceptor that rotates in proximity to the first and the second magnetic rolls. The first and the second magnetic rolls carry semiconductive carrier particles and toner particles through a development zone formed by the first and the second magnetic rolls.
Summarize the key points of the given document.
[ "TECHNICAL FIELD The present disclosure relates generally to an electrostatographic or xerographic printing machine, and more particularly concerns a development subsystem that uses semiconductive developer on a photoreceptor.", "BACKGROUND In the process of electrophotographic printing, a charge-retentive surface, also known as a photoreceptor, is charged to a substantially uniform potential, so as to sensitize the surface of the photoreceptor.", "The charged portion of the photoreceptor is exposed to a light image of an original document being reproduced, or else a scanned laser image created by the action of digital image data acting on a laser source.", "The scanning or exposing step records an electrostatic latent image on the photoreceptor corresponding to the informational areas in the document to be printed or copied.", "After the electrostatic latent image is recorded on the photoreceptor, the electrostatic latent image is developed by causing toner particles to adhere electrostatically to the charged areas forming the electrostatic latent image.", "This developed toner image on the photoreceptor is subsequently transferred to a sheet on which the desired image is to be printed.", "Finally, the toner on the sheet is heated to permanently fuse the toner image to the sheet.", "One familiar type of development of an electrostatic latent image is called “two-component development.”", "Two-component developer material largely comprises toner particles interspersed with carrier particles.", "The carrier particles are magnetically attractable, and the toner particles are caused to adhere triboelectrically to the carrier particles.", "This two-component developer can be conveyed, by means such as a “magnetic roll,” to the electrostatic latent image, where toner particles become detached from the carrier particles and adhere to the electrostatic latent image.", "In magnetic roll development systems, the carrier particles with the triboelectrically adhered toner particles are transported by the magnetic rolls through a development zone.", "The development zone is the area between the outside surface of a magnetic roll and the photoreceptor on which an electrostatic latent image has been formed.", "Because the carrier particles are attracted to the magnetic roll, some of the toner particles are interposed between a carrier particle and the electrostatic latent image on the photoreceptor.", "These toner particles are attracted to the electrostatic latent image and transfer from the carrier particles to the electrostatic latent image.", "The carrier particles are removed from the development zone as they continue to follow the rotating surface of the magnetic roll.", "The carrier particles then fall from the magnetic roll and return to the developer supply where they attract more toner particles and are reused in the development process.", "The carrier particles fall from the magnetic roll under the effects of gravity or are directed away from the roller surface by a magnetic field.", "Different types of carrier particles have been used in efforts to improve the development of toner from two-component developer with magnetic roll development systems.", "One type of carrier particle is a very electrically insulated carrier and development systems using developer having these carrier particles typically develop lines and fine detail with high fidelity.", "Development efficiency for solid areas, however, is increased through low magnetic field agitation in the development zone along with close spacing to the electrostatic latent image and elongation of the development zone.", "The magnetic field agitation helps prevent electric field collapse caused by toner countercharge in the development zone.", "The close spacing increases the effective electric field for a potential difference and the longer development zone provides more time for toner development.", "A disadvantage of this type of development system is the tendency for the carrier beads to retain countercharge left by toner particles that were developed from the brush.", "Retention of the countercharge causes carrier beads to be lost to the photoreceptor background areas.", "This loss is undesirable and leads to contamination problems in the xerographic system as well as depletion of the developer sump over time.", "Other two-component developers have used permanently magnetized carrier particles because these carrier particles dissipate toner countercharge more quickly by enabling a very dynamic mixing region to form on the magnetic roll.", "Another type of carrier particle used in two-component developers is an electrically conductive carrier particle.", "Developers using this type of carrier particle are capable of being used in magnetic roll systems that produce toner bearing substrates at speeds of up to approximately 100 pages per minute (ppm).", "These developers typically recruit toner for the electrostatic latent image from areas near the tip of the developer magnetic brush that are proximate the surface of the photoreceptor because the electric fields are high in this region.", "The electrical conductivity of the carrier particles serves to prevent development field collapse caused by the retention of toner countercharge and thereby allows high efficiency development, especially of solid area latent images.", "This type of developer, however, supplies an adequate amount of toner for high speed xerography with difficulty because the only toner available for development is the toner near the tip of the magnetic brush.", "Consequently, high development roller speeds are required.", "Unfortunately, high roller speeds increase the wear on the rollers and decrease the life of the rollers.", "Another problem that occurs with this type of developer is the tendency of the carrier particles, when the toner concentrations are low, to charge up in the image electric field.", "This charge causes the carrier particles to develop onto the image areas of the photoreceptor and leads to white spot deletions in the final image as well as carrier bead contamination in the system.", "Another type of carrier particle used in two-component developers is the semiconductive carrier particle.", "Developers using this type of carrier particle are also capable of being used in magnetic roll systems that produce toner bearing substrates at speeds of up to approximately 100 pages per minute (ppm).", "Developers having semiconductive carrier particles use a relatively thin layer of developer on the magnetic roll in the development zone.", "This feature allows more of the toner to be recruited during development than thick brush conductive developers allow.", "In these systems an AC electric waveform is applied to the magnetic roller to cause the developer to become electrically conductive during the development process.", "The electrically conductive developer increases the efficiency of development by preventing development field collapse due to countercharge left in the magnetic brush by the developed toner.", "A typical waveform applied to these systems is, for example, a square wave at a peak to peak amplitude of 1000 Volts and a frequency of 9 KHz.", "This waveform controls both the toner movement and the electric fields in the development zone.", "Typically these systems run in a “with”", "mode, which means the magnetic roll surface runs in the same direction as the photoreceptor.", "This movement in the same direction tends to keep background development low, but it has been observed to produce inadequate development unless high magnetic roll surface speeds are used to get an adequate supply of toner into the development zone.", "This high magnetic roll surface speed requires high strength magnets to control the developer bed.", "These types of magnets are expensive.", "Additionally, high speeds also increase the wear on bearings in the developer housing.", "Another limitation of known magnetic roll systems used with developers having semiconductive carrier particles is the difficulty in extending the development zone to increase the time in which toner development may occur.", "One method for increasing development zone length with other developers having insulated or conductive carrier particles is to use two magnetic rolls.", "The two rolls are placed close together with their centers aligned to form a line that is parallel to the photoreceptor.", "Because the developer layer for semiconductive carrier particle developer is so thin, magnetic fields sufficiently strong enough to cause semiconductive carrier particles to migrate in adequate quantities from one magnetic roll to the other magnetic roll also interfere with the transfer of toner from the carrier particles in the development zones.", "Consequently, construction of the magnetic rolls requires careful consideration of this interference.", "If two rolls are not able to be used to increase the development zone, then the radius of the magnetic roll may be increased to accommodate this goal.", "There is a limit, however, to the diameter of the magnetic roll.", "One limit is simply the area within the printing machine that is available for a development subsystem.", "Another limit is the size and strength of the magnets internal to the magnetic roll that are required to provide adequate magnetic field strengths and shapes at the surface of a larger magnetic roll.", "Another problem with semiconductive development systems is a defect in which the system has trouble developing a halftone adjacent and following a solid so a halo of the solid is left at the boundary of the halftone.", "This happens at high toner concentrations and limits the latitude of the system.", "The systems and methods discussed below address the limitations of development subsystems using developer having semiconductive carrier particles that have been noted.", "SUMMARY A development subsystem is used to develop toner having semiconductive carrier particles and toner particles.", "The development subsystem increases the time for developing the toner and provides an adequate supply of developer for good line detail, edges, and solids.", "The subsystem includes a developer housing, for retaining a quantity of developer having semiconductive carrier particles and toner particles, a first magnetic roll having a stationary core with at least one magnet and a sleeve that rotates about the stationary core of the first magnetic roll, a second magnetic roll having a stationary core with at least one magnet and a sleeve that rotates about the stationary core of the second magnetic roll, and a motor coupled to the first and the second magnetic rolls to drive the rotating sleeves of the first and the second magnetic rolls in a direction that is against the direction of a photoreceptor that rotates in proximity to the first and the second magnetic rolls.", "The first and the second magnetic rolls carry semiconductive carrier particles and toner particles through a development zone formed by the first and the second magnetic rolls.", "A method for developing developer having semiconductive carrier particles in an electrostatographic printing machine includes retaining a quantity of developer having semiconductive carrier particles and toner particles, transporting the developer through a development zone for development on a photoreceptor in a direction that is against the direction of the photoreceptor rotating through the development zone.", "The transportation of the developer in this method may be implemented by rotating a first sleeve about a first stationary core having at least one magnet, rotating a second sleeve about a second stationary core having at least one magnet, and the rotation of the first and the second sleeves occurs in a direction that is against the direction of the photoreceptor.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of an electrostatographic printing apparatus incorporating a semiconductive magnetic brush development (SCMB) system having two magnetic rolls.", "FIG. 2 is a sectional view of a SCMB developer unit having two magnetic rolls.", "FIG. 3 is a perspective view of a SCMB developer unit having two magnetic rolls.", "FIG. 4 is a perspective view of a SCMB developer unit showing the relationship of the two magnetic rolls to the path of the photoreceptor bearing a latent image.", "FIG. 5 is a perspective view of a magnetic roll used in the developer system shown in FIG. 2 .", "DETAILED DESCRIPTION FIG. 1 is an elevational view of an electrostatographic printing apparatus 10 , such as a printing machine, printer or copier, having a development subsystem that uses two magnetic rolls for developing toner particles that are carried on semiconductive carrier particles.", "The machine 10 includes a feeder unit 14 , a printing unit 18 , and an output unit 20 .", "The feeder unit 14 houses supplies of media sheets and substrates onto which document images are transferred by the printing unit 18 .", "Sheets to which images have been fixed are delivered to the output unit 20 for correlating and/or stacking in trays for pickup.", "The printing unit 18 includes an operator console 24 where job tickets may be reviewed and/or modified for print jobs performed by the machine 10 .", "The pages to be printed during a print job may be scanned by the machine 10 or received over an electrical communication link.", "The page images are used to generate bit data that are provided to a raster output scanner (ROS) 30 for forming a latent image on a photoreceptor 28 .", "Photoreceptor 28 continuously travels the circuit depicted in the figure in the direction indicated by the arrow.", "A development subsystem 26 develops toner on the photoreceptor 28 .", "At a transfer station 38 , the toner conforming to the latent image is transferred to the substrate by electric fields generated by the transfer station 38 .", "The substrate bearing the toner image travels to a fuser station 44 where the toner image is fixed to the substrate.", "The substrate is then carried to the output unit 20 .", "This description is provided to generally describe the environment in which a double magnetic roll development system for developer having semiconductive carrier particles may be used and is not intended to limit the use of such a development subsystem 26 to this particular printing machine environment.", "The overall function of a developer unit 100 , which is shown in FIG. 2 , is to apply marking material, such as toner, onto suitably-charged areas forming a latent image on an image receptor such as the photoreceptor 28 , in a manner generally known in the art.", "The developer unit 100 , however, provides a longer development zone while maintaining an adequate supply of developer having semiconductive carrier particles than development systems previously known.", "In various types of printers, there may be multiple such developer units 100 , such as one for each primary color or other purpose.", "Among the elements of the developer unit 100 , which is shown in FIG. 2 , are a housing 12 , which functions generally to hold a supply of developer material having semiconductive carrier particles, as well as augers, such as 30 , 32 , 34 , which variously mix and convey the developer material, and magnetic rolls 36 , 38 , which in this embodiment form magnetic brushes to apply developer material to the photoreceptor 28 .", "Other types of features for development of latent images, such as donor rolls, paddles, scavengeless-development electrodes, commutators, etc.", ", are known in the art and may be used in conjunction with various embodiments pursuant to the claims.", "In the illustrated embodiment, there is further provided air manifolds 40 , 42 , attached to vacuum sources (not shown) for removing dirt and excess particles from the transfer zone near photoreceptor 28 .", "As mentioned above, a two-component developer material is comprised of toner and carrier.", "The carrier particles in a two-component developer are generally not applied to the photoreceptor 28 , but rather remain circulating within the housing 12 .", "The augers 30 , 32 , and 34 are configured and cooperate in a manner described in co-pending applications entitled “Variable Pitch Auger To Improve Pickup Latitude In Developer Housing,” U.S. Ser.", "No. 11/263,370, which was filed on even date herewith, and “Developer Housing Design With Improved Sump Mass Variation Latitude,” U.S. Ser.", "No. 11/263,371, which was also filed on even date herewith, both of which are hereby expressly incorporated herein in their entireties by reference and are commonly assigned to the assignee of this patent application.", "FIG. 3 is a perspective view of a portion of developer unit 100 .", "As can be seen in this embodiment, the upper magnetic roll 36 and the lower magnetic roll 38 form a development zone that is approximately as long as the two diameters of the magnetic rolls 36 and 38 .", "As further can be seen, a motor 60 is used with a mechanism, generally indicated with reference numeral 62 , to cause rotation of the various augers 30 , 32 , 34 , magnetic rolls 36 and 38 , and any other rotatable members within the developer unit 100 at various relative velocities.", "There may be provided any number of such motors.", "The magnetic rolls 36 and 38 are rotated in a direction that is opposite to the direction in which the photoreceptor 28 moves past the developer unit 100 .", "That is, the two magnetic rolls 36 and 38 are operated in the against mode for development of toner.", "In one embodiment of the developer unit 100 , the motor 60 and the mechanism 62 cause the magnetic rolls 36 and 38 to rotate at a speed in the range of about 1 to about 1.5 times the rotational speed of the photoreceptor 28 .", "This rotational speed is lower than the rotational speed of magnetic rolls in developer systems that rotate in the same direction as the photoreceptor 28 .", "That is, the magnetic rolls operated in the against mode may be rotated at lower speeds than magnetic rolls operated in the with mode.", "These slower speeds increase the life of the magnetic rolls over the life of magnetic rolls that are operated in the with mode to develop toner carried on semiconductive carrier particles.", "FIG. 4 shows the relationship of the photoreceptor 28 to the developer unit 100 within a printing machine, such as the machine 10 shown in FIG. 1 .", "In this arrangement, the lower magnetic roll 38 develops approximately 70% of the toner that is developed in the development zone of the developer unit 100 and the upper magnetic roll 36 develops approximately 30% of the toner.", "The upper magnetic roll 36 also cleans up the carrier particles from the development zone.", "The two magnetic roll arrangement operating in the against mode is able to develop toner carried by semiconductive carrier particles while maintaining fine line and edge development at speeds from 100 to over 200 ppm.", "As is well known, magnetic rolls, such as magnetic rolls 36 and 38 , are comprised of a rotating sleeve and a stationary core in which magnets are housed.", "In order to provide a surface that impedes the slippage of carrier particles as the outer sleeve rotates, the outer surface of the rotating sleeve may be sand-blasted or grooved.", "Previously known SCMB systems used sand-blasted stainless steel rollers, but these rollers have relatively short functional life of approximately 2 million prints or copies.", "Other known magnetic brush systems that use other types of developers used grooved stainless steel rollers having a depth of approximately 200 to 250 microns.", "The use of these grooved rollers in a double magnetic roller development subsystem operating in the against mode reduced the trim gap for the development subsystem from approximately 0.7 mm to approximately 0.135 mm.", "The trim gap is the distance between the trim blade and the upper magnetic roll 36 .", "The trim blade assists in the removal of excess developer from the upper magnetic roll 36 before it is carried into the development zone.", "A narrow trim gap presents issues with respect to the manufacturing of the developer unit.", "For one, the tolerances for the components that comprise the trim blade that assists in the removal of carrier particles from the upper magnetic roll are more difficult to meet.", "More precise manufacturing techniques and higher rejection rates increase the unit manufacturing cost for the trim blade.", "Additionally, a narrower trim gap requires greater torque from the motor driving the roller and it also increases the aging of the developer.", "In an embodiment that uses stainless rollers to provide relatively long life for the rollers, for example, 20 million prints, the rollers are made of stainless steel that has been machined with longitudinal grooves that support a trim gap of approximately 0.5 mm to approximately 0.7 mm.", "To increase the trim gap to this distance, the rotating sleeves were machined with grooves as shown, for example, in FIG. 5 .", "The grooves 200 are machined across the face of the rotating sleeve 204 .", "The grooves 200 are approximately 1.2 mm to approximately 1.4 mm apart.", "The area between the grooves 200 may be sandblasted, however, surfaces that are relatively smooth between the grooves 200 support more acceptable trim gaps.", "In one embodiment, the surface roughness of sleeve 204 between the grooves is less than about 2.0 Rz.", "The grooves 200 assist in maintaining the semiconductive carrier particles on the magnetic rolls as they move through the development zone.", "In one embodiment, the grooves 200 are preferably cut in either a U or a V shape, although other shapes may be used.", "The U or V-shaped grooves may be formed in one of two manners.", "In one construction, the sides of the U or the V-shaped grooves may have the same pitch, but the U-shaped grooves are deeper than the V-shaped grooves.", "In the other construction, the U and V-shaped grooves may have the same depth, but the U-shaped grooves have sides with a pitch that are shallower than the sides of the V-shaped grooves.", "As shown in the figure, the sides of a groove 200 are oriented at an angle of approximately 90°±10° and pitched to be a length of about 1.2 to about 1.4 mm.", "The depth of a groove 200 is approximately 90 to 100 microns.", "These groove parameters may be used with a trim magnet having a pole strength of approximately 400 to 600 gauss.", "Of course, these parameters may be altered for other roll dimensions or trim magnet pole strengths.", "A pair of magnetic rolls having the grooves described above was capable of being long life stainless steel sleeves that operated with a trim gap of approximately 0.5 to 0.7 mm, instead of the 0.135 mm gap experienced with the magnetic rolls having rotating sleeves that had grooves of approximately 200 microns to 250 microns.", "Although the various embodiments described above have been discussed with regard to an arrangement in which the developer is distributed from an upper magnetic roll to a lower magnetic roll, the reverse may also be used in another embodiment.", "In such an embodiment, the developer having semiconductive carrier particles is picked up by the lower magnetic roll and then transferred from the lower magnetic roll to the upper magnetic roll.", "At the upper magnetic roll, the semiconductive carrier particles are removed by gravity or the magnetic field generated by one or more magnets in the upper magnetic roll or a combination of gravity and magnetic fields.", "The removed carrier particles are returned to the developer supply.", "The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others." ]
BACKGROUND OF THE INVENTION This invention relates to heating devices and more particularly to a device for attaching modular electronic components to or removing them from a substrate such as a printed circuit board. Present day devices for removing or installing modular electronic components from a substrate such as a printed circuit board generally fall into two categories: those which use a heated head which contacts each terminal to melt the solder thereon or those which use a blast of hot air to melt the solder. The former devices are generally very complex and employ a heated head having a plurality of spaced apart fingers each of which must be precisely aligned with each terminal around the component to simultaneously heat the solder on it. The component is then withdrawn from the substrate by vacuum suction or other mechanical means. The procedure is reversed for installing a component. An example of such a device is disclosed in U.S. Pat. No. 3,382,564. A major disadvantage of this type of device is that, due to the ever-increasing miniaturization of electronic systems and individual components in them, the terminals of such components are extremely close together thus making precise alignment of the fingers of the heating head therewith extremely difficult. Improper alignment or contact often results in solder flowing between terminals on the component thus shorting them or otherwise damaging them. The latter devices direct a blast of hot air at the terminals from a source above the component to simultaneously melt the solder on each. Such a device, for example, is set forth in U.S. Pat. No. 4,366,925. Such a device may function satisfactorily if there is a large spacing between components such that the blast of hot air directed at one component from above will not spill over and melt the solder on the terminals of adjacent components. However, as aforementioned, not only are the components themselves becoming increasingly smaller but their proximity on the printed circuit substrate is also increasing. Thus, there is a need for a device which not only can provide a closely controlled and evenly distributed source of heat sufficient to melt solder associated with component terminals or printed substrate conductors during installation or removal of the electronic component relative thereto but one which also can rapidly and precisely direct this controlled heat where desired thereby minimizing the likelihood of melting the solder on the terminals of adjacent components or otherwise damaging the printed conductors on the substrate. There is also a need for a device of the subject type which has the capability of precisely positioning the electronic component and its terminals on the ends of the printed conductors on the substrate to insure no overlapping as well as removing the component to insure that no liquid solder is smeared on the substrate between the conductors printed thereon. It is therefore the primary object of the present invention to provide a superior device for installation and removal of electronic components from circuits printed on a substrate. It is another object of the present invention to provide a device of the subject type which employs a series of stacked nozzles for precisely directing the flow of hot air from a source simultaneously to the solder associated with each component terminal or printed conductor on the substrate. It is yet another object of the present invention to provide a device wherein the aforementioned nozzles can be both rapidly changed to correspond to the different size of various electronic components as well as moved separately or together to a location to permit cleaning or other preparation of the substrate without shutting off the source of heated air. It is a further object of the present invention to provide a device which has means for rapidly and accurately positioning the substrate and the electronic component to be installed or removed beneath the source of heated air. It is a still further object of the present invention to provide a device which has a vacuum means axially aligned with the source of heated air and directing nozzles for positioning the electronic component on or removing it from the substrate. BRIEF DESCRIPTION OF THE DRAWING Other objects, details and advantages of the invention will be more readily apparent in the light of the explanation which follows of a preferred embodiment of a device according to the invention, given only by way of example and with references to the accompanying drawing in which: FIG. 1 is a front elevational view of the device of the subject invention; FIG. 2 is a side elevational view in partial cross-section taken along the lines 2--2 of FIG. 1; FIG. 3 is a plan view of the device shown in FIG. 1; FIG. 4 is a side elevational view taken along lines 4--4 of FIG. 1; FIG. 5 is a cross-sectional view of the heater assembly taken along the lines 5--5 of FIG. 2; FIG. 6 is a view in partial cross-section of a nozzle taken along the lines 6--6 of FIG. 2; FIG. 7 is an enlarged cross-sectional view taken along the lines 7--7 of FIG. 6; FIG. 8 is a view of the locator nozzle taken along the lines 8--8 of FIG. 2; FIG. 9 is a plan view of the holder assembly with a chip located in position; and FIG. 10 is a cross-sectional view taken along the lines 10--10 of FIG. 9. DESCRIPTION OF PREFERRED EMBODIMENT Referring now to the drawings where like characters of reference refer to similar elements in each of the several views, numeral 10 indicates generally the device of the present invention for attaching modular electronic components to or removing them from an insulative substrate. More specifically, referring to FIGS. 1-4, the device 10 comprises a main frame element 12 having a base section 14, a mounting section 16 parallel to the base section 14, a vertical section 18 and a top mounting arm 20 extending from the vertical section 18 parallel to the base section 14. A rectangular shaped rod 22 is slidably mounted between a groove 24 in the base section 14 and a groove 26 in a clamp 28 secured to the base 14. A fixed block 30 is secured at one end of the rod 22 and has a V-shaped recess 32 formed therein for supporting an edge of a substrate or printed circuit board 34 as it is often called. The opposite edge of the substrate 34 is supported in a similar shaped recess 36 of a spring clip 38. The spring clip 38 in turn is secured to a block 40 which is slidable on the other end of the rod 22. A knob 37 having a shaft 39 in threaded engagement with base section 14 is provided which can be rotated into engagement with the underside of the substrate 34 to support the middle of same. The substrate 34 generally has a plurality of electronic components 42 positioned thereon which have connection terminals 44 extending around the periphery thereof (see FIG. 9). The terminals 44 are soldered to conductors 46 of an interconnection network on the top surface as well as between various layers of the substrate which is typically made of an insulative, ceramic material. The electronic component 42 can thus be positioned in one direction by moving the substrate 34 in recesses 32, 36 and in a direction ninety-degrees relative to that direction by sliding the rod 22 in the grooves 24, 26. A shaft 48 is secured at one of its ends to the top mounting arm 20 and extends downward toward the base section 14. An assembly 50 for heating the solder associated with the terminals 44 and conductor 46 of the electronic component 42 and lifting it from the substrate 34 is mounted for vertical as well as horizontal movement on the shaft 48. The assembly 50 comprises a mounting block 52 which is journaled on the shaft 48 and can be rotated as described below under "OPERATION", or raised and lowered by means of handle 54. The mounting block 52 has a cylindrical shaped cavity 56 formed therein and an inward, radially extending lip 58 which terminates at passageway 60 that connects an upper chamber 62 with a lower chamber 64. A heating element 66 of the electrical resistance type is positioned in the upper chamber 62 on the lip 58. The heating element 66 is cylindrical in shape and has a plurality of throughpassages 68 extending the length thereof for heating a fluid such as air passing through as will be more fully described later. Although air is mentioned herein as the fluid to be heated, it is to be understood that various types of gases, be they inert or not, are also contemplated to be used. A plug 70 is provided in the mounting block 52 to 62. The plug 70 has a enclose the end of the upper chamber circumferential recess 72 from which inlet ports 74 extend inwardly to an opening 76. A base 78 through the mounting block 52 communicates at one end with the recess 72 and is connected at the other end to a tube 80 as can best be seen in FIG. 5. Air under pressure is delivered to the tube 80 by hose 82 from a source 84 which consists of a pneumatic pump secured to the mounting section 16 and enclosed by housing 85. The pump 84 has a pressure side 86 and a vacuum side 88 with filters 90. The electric motor (not shown) of the pump 84 has one end 92 of its shaft exposed. A flexible drive shaft (also not shown) can be connected to shaft 92 to power small hand-held drills, wire wheels and the like to perform minor repair and cleaning operations on the substrate 34. The remainder of the upper chamber 62 is filled with an insulating material 93 to prevent dissipation of heat from the heating element 66 and maximize heating of the air traveling in through passages 68. A heat sensing element 94 in the form of a thermistor is located in the lower chamber 64 to sense the temperature of the air passing therethrough to thereby control the energization of the heating element 66 to maintain it at a preselected level. Energization of the heating element circuit (not shown) is controlled by switch 96 located on control panel 98. A light 100 is also provided to indicate when the heating element 66 is in operation. Wires from the thermistor 94 and heating element 66 are carried in flexible conduit 95. An elongated vacuum tube 102 is slidably mounted in the plug 70 and extends through a bore 104 in the heating element 66, through the lower chamber 64 to a first position shown in FIG. 2. The vacuum tube is maintained in this first position by means of a compression spring 106 acting between the plug 70 and fitting 108 on the upper end thereof. A retainer ring 110 is provided to limit upward travel of the vacuum tube 102. The vacuum tube 102 is also connected by a hose 112 secured at one end to the fitting 108 and the other end to the vacuum side 88 of the pump 84 by way of a vacuum control valve 114 located on the panel 98. Actuation of the vacuum control valve 114 by pressing on button 116 causes a vacuum to be created in the vacuum tube 102 and at the end 103 thereof for removing an electronic component 42 as will be more fully described later. Referring now to FIGS. 2, 6, 7 and 8, a nozzle plate 118 is secured by side flanges 120 to the opening in the mounting block 52 adjacent the lower chamber 64. The nozzle plate 118 has a plurality of nozzle orifices 122 formed therethrough which have sides tapered at an angle of approximately 30 degrees with respect to each other. The orifices 122 are arranged in a rectangular shape which generally corresponds to the shape of the outer perimeter of the electronic component 42. A holder 124 is also mounted on the shaft 48 and it is capable of vertical as well as horizontal (rotational) movement as is the block 52. The holder 124 has a rectangular shaped opening 126 adjacent to which are two oppositely disposed guide pins 128. A locator nozzle 130 has a base 132 and a flanged portion 133 which is inserted in the opening 126 and retained by guide pins 128. The base 132 has notches 134 the function of which will be described shortly. The flanged portion 133 has an opening 136 which is the same shape but is slightly larger than the perimeter of the electronic component 42. With the assembly 50 raised and rotated out of the way, the electronic component 42 can be viewed through the opening 136 from above and positioned so that it is equidistant or centered within the opening 136. The locator nozzle 130 can be attached to the assembly 50 and rotated out of the way therewith by means of clips 138 which engage the notches 134 as best seen in the cut away view shown in FIG. 1. With the locator nozzle 130 rotated out of the way, an aligning plate 140 can be installed on the guide pins 128 as shown in FIGS. 9 and 10. The aligning plate 140 has wires 142 crossed at 90 degrees with respect to each other and secured in the corners of the opening 144. Thus, when the corners of the electronic component 42 are each beneath one of the wires 142, the component is precisely centered in the opening 144. After the electronic component 142 is centered, the plate 140 is removed and the assembly 50 together with locator nozzle 130 is returned for removal or installation of the component as will be fully described with the explanation of the operation of the device. A platform 146 is secured to the vertical section 18 and extends outwardly therefrom. The platform 146 acts to shield the substrate 34 and electronic components 42 thereon from the heated air emmanating from opening 136 when the assembly 50 is in the rotated position. In order to accurately position the opening 136 of the locator nozzle 130 a predetermined distance above the substrate 34, a nut 148 is provided threaded on the shaft 48 which can be raised and lowered by rotation to thereby limit downward travel of the mounting block 52 and locator nozzle clipped thereto. A timer 150 is located on the panel 98 which can be set to provide an audible alarm when the set time limit has expired. The operation of the timer is started by closure of a microswitch 152 mounted by a bracket 153 having an actuating arm 154 and roller 156 thereon. A cam surface 158 on the mounting block 52 is engaged by the roller 156 to operate the switch 152 when the assembly 50 is lowered into operating position. An electrical outlet 160 is also provided on the panel 98 into which can be plugged various auxiliary devices such as a hand held desoldering and vacuum solder removing device (not shown) for cleaning and repair work. The degree of energization of the device 160 and thus its temperature can be adjusted by controller 162. A source of vacuum 164 is also located on the panel 98 as is a source of air under pressure 166 for blowing debris from the substrate 34 to assist in cleaning it. OPERATION Energization of the heater element 66 by actuation of switch 96 also starts pump 84 to provide both a source of air under pressure as well as a source of vacuum. With the vacuum in tube 102 shut off by control valve 114, a locator nozzle 130 is selected having an opening 136 slightly larger than the perimeter of the electronic component to be installed or removed and this is clipped onto the mounting block 52. The entire assembly 50 and locator nozzle 130 are then rotated and lowered to a position where the platform 146 covers the opening 136 to thereby prevent hot gasses from damaging the substrate 34. If the electronic component 42 is to be removed from the substrate 34, the aligning plate 140 is positioned on the holder 124 and the component is aligned beneath the crosswires 142 by sliding the substrate in the grooves 32, 36 and positioning it by moving rod 22. After the electronic component 42 is aligned, the aligning plate 140 is removed and the assembly 50 rotated such that the locator nozzle 130 is above the opening 126 in the holder 124. A time sufficient to insure proper melting of the connecting solder is selected on timer 150 and the assembly 50 and locator nozzle 130 are lowered to a position above the terminals 44 on the electronic component 42 as preselected by the location of nut 148. At this location, the opening 136 of the locator nozzle 130 is spaced apart a short distance from the substrate 34 which is just sufficient to permit the heated air to escape out. Lowering of the assembly 50 caused energization of the timer by switch 152. During this period, air under pressure from the pump 84 flows through the bore 78 into recess 72 and from there through inlet ports 74 into opening 76 above the heating element 66. As the air flows downward (see arrows) in through passages 68 it is heated to a preselected solder melting temperature. The air thus heated exits through passages 68 into the lower chamber 64 and from there through nozzle orifices 122 where it is converted into a plurality of jet streams. These jet streams are then guided by the wall of locator nozzle 130 to the opening thereof 136. As the heated air exits the opening 136 it heats the solder between the terminals 44 and conductors 46 thus melting the solder and freeing electronic component 42 which should coincide with expiration of the time on the timer 150 as indicated, for example, by an audible signal. At this time, the vacuum control valve 114 is acutated causing a vacuum in tube 102 and at the end 103 thereof. Manual downward pressure on the button 116 causes the end 103 to engage the electronic component 42 which will then adhere to the end 103 as the tube returns to its rest position. The assembly 50 and locator nozzle 130 are then raised, rotated and lowered onto platform 146. The holder 124 can also be rotated with the assembly 50 at this time to clear the area above the site. After the site has been cleaned and prepared by the auxiliary equipment aforementioned, a new electronic component can be positioned on the conductors 46 by the aligning plate 140 on holder 124 and soldered thereto by again lowering the assembly 50 and locator nozzle 130 adjacent thereto for a timed period. Applicant has thus disclosed his novel device for rapidly and accurately removing electronic components from or installing them on a substrate. However, it is not intended to limit the invention to the embodiment of the device which has just been described and it is intended by the appended claims to include all technically equivalent means which come within the full scope and true spirit of the invention.
A device is disclosed for attaching to or removing modular electronic components from a substrate which is adjustably positioned beneath a heater means delivering a flow of uniformly heated air. The heated air is directed to the sides of the component to melt solder associated with terminals thereon by a series of changable nozzles which can be moved into or out of registry with the component. Vacuum means is also provided for contacting the component to position it on or remove it from the substrate.
Briefly summarize the invention's components and working principles as described in the document.
[ "BACKGROUND OF THE INVENTION This invention relates to heating devices and more particularly to a device for attaching modular electronic components to or removing them from a substrate such as a printed circuit board.", "Present day devices for removing or installing modular electronic components from a substrate such as a printed circuit board generally fall into two categories: those which use a heated head which contacts each terminal to melt the solder thereon or those which use a blast of hot air to melt the solder.", "The former devices are generally very complex and employ a heated head having a plurality of spaced apart fingers each of which must be precisely aligned with each terminal around the component to simultaneously heat the solder on it.", "The component is then withdrawn from the substrate by vacuum suction or other mechanical means.", "The procedure is reversed for installing a component.", "An example of such a device is disclosed in U.S. Pat. No. 3,382,564.", "A major disadvantage of this type of device is that, due to the ever-increasing miniaturization of electronic systems and individual components in them, the terminals of such components are extremely close together thus making precise alignment of the fingers of the heating head therewith extremely difficult.", "Improper alignment or contact often results in solder flowing between terminals on the component thus shorting them or otherwise damaging them.", "The latter devices direct a blast of hot air at the terminals from a source above the component to simultaneously melt the solder on each.", "Such a device, for example, is set forth in U.S. Pat. No. 4,366,925.", "Such a device may function satisfactorily if there is a large spacing between components such that the blast of hot air directed at one component from above will not spill over and melt the solder on the terminals of adjacent components.", "However, as aforementioned, not only are the components themselves becoming increasingly smaller but their proximity on the printed circuit substrate is also increasing.", "Thus, there is a need for a device which not only can provide a closely controlled and evenly distributed source of heat sufficient to melt solder associated with component terminals or printed substrate conductors during installation or removal of the electronic component relative thereto but one which also can rapidly and precisely direct this controlled heat where desired thereby minimizing the likelihood of melting the solder on the terminals of adjacent components or otherwise damaging the printed conductors on the substrate.", "There is also a need for a device of the subject type which has the capability of precisely positioning the electronic component and its terminals on the ends of the printed conductors on the substrate to insure no overlapping as well as removing the component to insure that no liquid solder is smeared on the substrate between the conductors printed thereon.", "It is therefore the primary object of the present invention to provide a superior device for installation and removal of electronic components from circuits printed on a substrate.", "It is another object of the present invention to provide a device of the subject type which employs a series of stacked nozzles for precisely directing the flow of hot air from a source simultaneously to the solder associated with each component terminal or printed conductor on the substrate.", "It is yet another object of the present invention to provide a device wherein the aforementioned nozzles can be both rapidly changed to correspond to the different size of various electronic components as well as moved separately or together to a location to permit cleaning or other preparation of the substrate without shutting off the source of heated air.", "It is a further object of the present invention to provide a device which has means for rapidly and accurately positioning the substrate and the electronic component to be installed or removed beneath the source of heated air.", "It is a still further object of the present invention to provide a device which has a vacuum means axially aligned with the source of heated air and directing nozzles for positioning the electronic component on or removing it from the substrate.", "BRIEF DESCRIPTION OF THE DRAWING Other objects, details and advantages of the invention will be more readily apparent in the light of the explanation which follows of a preferred embodiment of a device according to the invention, given only by way of example and with references to the accompanying drawing in which: FIG. 1 is a front elevational view of the device of the subject invention;", "FIG. 2 is a side elevational view in partial cross-section taken along the lines 2--2 of FIG. 1;", "FIG. 3 is a plan view of the device shown in FIG. 1;", "FIG. 4 is a side elevational view taken along lines 4--4 of FIG. 1;", "FIG. 5 is a cross-sectional view of the heater assembly taken along the lines 5--5 of FIG. 2;", "FIG. 6 is a view in partial cross-section of a nozzle taken along the lines 6--6 of FIG. 2;", "FIG. 7 is an enlarged cross-sectional view taken along the lines 7--7 of FIG. 6;", "FIG. 8 is a view of the locator nozzle taken along the lines 8--8 of FIG. 2;", "FIG. 9 is a plan view of the holder assembly with a chip located in position;", "and FIG. 10 is a cross-sectional view taken along the lines 10--10 of FIG. 9. DESCRIPTION OF PREFERRED EMBODIMENT Referring now to the drawings where like characters of reference refer to similar elements in each of the several views, numeral 10 indicates generally the device of the present invention for attaching modular electronic components to or removing them from an insulative substrate.", "More specifically, referring to FIGS. 1-4, the device 10 comprises a main frame element 12 having a base section 14, a mounting section 16 parallel to the base section 14, a vertical section 18 and a top mounting arm 20 extending from the vertical section 18 parallel to the base section 14.", "A rectangular shaped rod 22 is slidably mounted between a groove 24 in the base section 14 and a groove 26 in a clamp 28 secured to the base 14.", "A fixed block 30 is secured at one end of the rod 22 and has a V-shaped recess 32 formed therein for supporting an edge of a substrate or printed circuit board 34 as it is often called.", "The opposite edge of the substrate 34 is supported in a similar shaped recess 36 of a spring clip 38.", "The spring clip 38 in turn is secured to a block 40 which is slidable on the other end of the rod 22.", "A knob 37 having a shaft 39 in threaded engagement with base section 14 is provided which can be rotated into engagement with the underside of the substrate 34 to support the middle of same.", "The substrate 34 generally has a plurality of electronic components 42 positioned thereon which have connection terminals 44 extending around the periphery thereof (see FIG. 9).", "The terminals 44 are soldered to conductors 46 of an interconnection network on the top surface as well as between various layers of the substrate which is typically made of an insulative, ceramic material.", "The electronic component 42 can thus be positioned in one direction by moving the substrate 34 in recesses 32, 36 and in a direction ninety-degrees relative to that direction by sliding the rod 22 in the grooves 24, 26.", "A shaft 48 is secured at one of its ends to the top mounting arm 20 and extends downward toward the base section 14.", "An assembly 50 for heating the solder associated with the terminals 44 and conductor 46 of the electronic component 42 and lifting it from the substrate 34 is mounted for vertical as well as horizontal movement on the shaft 48.", "The assembly 50 comprises a mounting block 52 which is journaled on the shaft 48 and can be rotated as described below under "OPERATION", or raised and lowered by means of handle 54.", "The mounting block 52 has a cylindrical shaped cavity 56 formed therein and an inward, radially extending lip 58 which terminates at passageway 60 that connects an upper chamber 62 with a lower chamber 64.", "A heating element 66 of the electrical resistance type is positioned in the upper chamber 62 on the lip 58.", "The heating element 66 is cylindrical in shape and has a plurality of throughpassages 68 extending the length thereof for heating a fluid such as air passing through as will be more fully described later.", "Although air is mentioned herein as the fluid to be heated, it is to be understood that various types of gases, be they inert or not, are also contemplated to be used.", "A plug 70 is provided in the mounting block 52 to 62.", "The plug 70 has a enclose the end of the upper chamber circumferential recess 72 from which inlet ports 74 extend inwardly to an opening 76.", "A base 78 through the mounting block 52 communicates at one end with the recess 72 and is connected at the other end to a tube 80 as can best be seen in FIG. 5. Air under pressure is delivered to the tube 80 by hose 82 from a source 84 which consists of a pneumatic pump secured to the mounting section 16 and enclosed by housing 85.", "The pump 84 has a pressure side 86 and a vacuum side 88 with filters 90.", "The electric motor (not shown) of the pump 84 has one end 92 of its shaft exposed.", "A flexible drive shaft (also not shown) can be connected to shaft 92 to power small hand-held drills, wire wheels and the like to perform minor repair and cleaning operations on the substrate 34.", "The remainder of the upper chamber 62 is filled with an insulating material 93 to prevent dissipation of heat from the heating element 66 and maximize heating of the air traveling in through passages 68.", "A heat sensing element 94 in the form of a thermistor is located in the lower chamber 64 to sense the temperature of the air passing therethrough to thereby control the energization of the heating element 66 to maintain it at a preselected level.", "Energization of the heating element circuit (not shown) is controlled by switch 96 located on control panel 98.", "A light 100 is also provided to indicate when the heating element 66 is in operation.", "Wires from the thermistor 94 and heating element 66 are carried in flexible conduit 95.", "An elongated vacuum tube 102 is slidably mounted in the plug 70 and extends through a bore 104 in the heating element 66, through the lower chamber 64 to a first position shown in FIG. 2. The vacuum tube is maintained in this first position by means of a compression spring 106 acting between the plug 70 and fitting 108 on the upper end thereof.", "A retainer ring 110 is provided to limit upward travel of the vacuum tube 102.", "The vacuum tube 102 is also connected by a hose 112 secured at one end to the fitting 108 and the other end to the vacuum side 88 of the pump 84 by way of a vacuum control valve 114 located on the panel 98.", "Actuation of the vacuum control valve 114 by pressing on button 116 causes a vacuum to be created in the vacuum tube 102 and at the end 103 thereof for removing an electronic component 42 as will be more fully described later.", "Referring now to FIGS. 2, 6, 7 and 8, a nozzle plate 118 is secured by side flanges 120 to the opening in the mounting block 52 adjacent the lower chamber 64.", "The nozzle plate 118 has a plurality of nozzle orifices 122 formed therethrough which have sides tapered at an angle of approximately 30 degrees with respect to each other.", "The orifices 122 are arranged in a rectangular shape which generally corresponds to the shape of the outer perimeter of the electronic component 42.", "A holder 124 is also mounted on the shaft 48 and it is capable of vertical as well as horizontal (rotational) movement as is the block 52.", "The holder 124 has a rectangular shaped opening 126 adjacent to which are two oppositely disposed guide pins 128.", "A locator nozzle 130 has a base 132 and a flanged portion 133 which is inserted in the opening 126 and retained by guide pins 128.", "The base 132 has notches 134 the function of which will be described shortly.", "The flanged portion 133 has an opening 136 which is the same shape but is slightly larger than the perimeter of the electronic component 42.", "With the assembly 50 raised and rotated out of the way, the electronic component 42 can be viewed through the opening 136 from above and positioned so that it is equidistant or centered within the opening 136.", "The locator nozzle 130 can be attached to the assembly 50 and rotated out of the way therewith by means of clips 138 which engage the notches 134 as best seen in the cut away view shown in FIG. 1. With the locator nozzle 130 rotated out of the way, an aligning plate 140 can be installed on the guide pins 128 as shown in FIGS. 9 and 10.", "The aligning plate 140 has wires 142 crossed at 90 degrees with respect to each other and secured in the corners of the opening 144.", "Thus, when the corners of the electronic component 42 are each beneath one of the wires 142, the component is precisely centered in the opening 144.", "After the electronic component 142 is centered, the plate 140 is removed and the assembly 50 together with locator nozzle 130 is returned for removal or installation of the component as will be fully described with the explanation of the operation of the device.", "A platform 146 is secured to the vertical section 18 and extends outwardly therefrom.", "The platform 146 acts to shield the substrate 34 and electronic components 42 thereon from the heated air emmanating from opening 136 when the assembly 50 is in the rotated position.", "In order to accurately position the opening 136 of the locator nozzle 130 a predetermined distance above the substrate 34, a nut 148 is provided threaded on the shaft 48 which can be raised and lowered by rotation to thereby limit downward travel of the mounting block 52 and locator nozzle clipped thereto.", "A timer 150 is located on the panel 98 which can be set to provide an audible alarm when the set time limit has expired.", "The operation of the timer is started by closure of a microswitch 152 mounted by a bracket 153 having an actuating arm 154 and roller 156 thereon.", "A cam surface 158 on the mounting block 52 is engaged by the roller 156 to operate the switch 152 when the assembly 50 is lowered into operating position.", "An electrical outlet 160 is also provided on the panel 98 into which can be plugged various auxiliary devices such as a hand held desoldering and vacuum solder removing device (not shown) for cleaning and repair work.", "The degree of energization of the device 160 and thus its temperature can be adjusted by controller 162.", "A source of vacuum 164 is also located on the panel 98 as is a source of air under pressure 166 for blowing debris from the substrate 34 to assist in cleaning it.", "OPERATION Energization of the heater element 66 by actuation of switch 96 also starts pump 84 to provide both a source of air under pressure as well as a source of vacuum.", "With the vacuum in tube 102 shut off by control valve 114, a locator nozzle 130 is selected having an opening 136 slightly larger than the perimeter of the electronic component to be installed or removed and this is clipped onto the mounting block 52.", "The entire assembly 50 and locator nozzle 130 are then rotated and lowered to a position where the platform 146 covers the opening 136 to thereby prevent hot gasses from damaging the substrate 34.", "If the electronic component 42 is to be removed from the substrate 34, the aligning plate 140 is positioned on the holder 124 and the component is aligned beneath the crosswires 142 by sliding the substrate in the grooves 32, 36 and positioning it by moving rod 22.", "After the electronic component 42 is aligned, the aligning plate 140 is removed and the assembly 50 rotated such that the locator nozzle 130 is above the opening 126 in the holder 124.", "A time sufficient to insure proper melting of the connecting solder is selected on timer 150 and the assembly 50 and locator nozzle 130 are lowered to a position above the terminals 44 on the electronic component 42 as preselected by the location of nut 148.", "At this location, the opening 136 of the locator nozzle 130 is spaced apart a short distance from the substrate 34 which is just sufficient to permit the heated air to escape out.", "Lowering of the assembly 50 caused energization of the timer by switch 152.", "During this period, air under pressure from the pump 84 flows through the bore 78 into recess 72 and from there through inlet ports 74 into opening 76 above the heating element 66.", "As the air flows downward (see arrows) in through passages 68 it is heated to a preselected solder melting temperature.", "The air thus heated exits through passages 68 into the lower chamber 64 and from there through nozzle orifices 122 where it is converted into a plurality of jet streams.", "These jet streams are then guided by the wall of locator nozzle 130 to the opening thereof 136.", "As the heated air exits the opening 136 it heats the solder between the terminals 44 and conductors 46 thus melting the solder and freeing electronic component 42 which should coincide with expiration of the time on the timer 150 as indicated, for example, by an audible signal.", "At this time, the vacuum control valve 114 is acutated causing a vacuum in tube 102 and at the end 103 thereof.", "Manual downward pressure on the button 116 causes the end 103 to engage the electronic component 42 which will then adhere to the end 103 as the tube returns to its rest position.", "The assembly 50 and locator nozzle 130 are then raised, rotated and lowered onto platform 146.", "The holder 124 can also be rotated with the assembly 50 at this time to clear the area above the site.", "After the site has been cleaned and prepared by the auxiliary equipment aforementioned, a new electronic component can be positioned on the conductors 46 by the aligning plate 140 on holder 124 and soldered thereto by again lowering the assembly 50 and locator nozzle 130 adjacent thereto for a timed period.", "Applicant has thus disclosed his novel device for rapidly and accurately removing electronic components from or installing them on a substrate.", "However, it is not intended to limit the invention to the embodiment of the device which has just been described and it is intended by the appended claims to include all technically equivalent means which come within the full scope and true spirit of the invention." ]
TECHNICAL FIELD [0001] The present invention relates generally to data types, and in particular to a composite tree data type representing tree based documents and objects. BACKGROUND [0002] Tree-structured based documents and objects are popular formats for storing and exchanging data. XML, for example, is a tree-structure based document widely used for exchanging data, and is also becoming a data type commonly stored in databases and queried by users. Service Data Objects (SDO) have also become popular as an object format for data transfer in the field of integration. [0003] In the conventional way of representing tree-structure based documents and objects, the documents/objects are considered as a whole or a single unit. For example, XML content is perceived as a single entity, and the individual elements making up the XML content, such as the structure, labels, values and contents, are not looked upon or considered as separate entities. Such a representation encounters the disadvantages of: (a) Unnecessary repetition: if a large number of documents have many elements in common, multiple copies are still required to contain them; and (b) Loss of flexibility: if for example there is a need to modify the structure or content type of the document separately, the entire document needs to change. [0006] United States Patent Application No. 20060031233A1 describes a universal format that is used to create a type representation of XMLType instances that are generated in various ways from various sources. An XMLType Type Tree is represented as a hierarchy of nodes, including a leaf item node, composite item node, operator node, and aggregate node, referred to herein as an XMLType Type Tree. An XMLType Type Tree serves as a digest of the type structure of XMLType, no matter the source of the XMLType instance or its manner of generation, and it creates one uniform abstraction of the type structure of XMLType for the data-typing analysis of XPath and XQuery during query compile time. [0007] United States Patent Application No. 20020087596 describes a document written in a markup language, represented by a unique data structure. A virtual node tree describes the structure of the data types in the document. Each one of the nodes in the virtual node tree respectively corresponds to one of the data types in the document. A data array corresponding to each one of the nodes in the virtual node tree includes information identifying the relationship of the node to other nodes in the virtual node tree and a reference indicating the location of the data corresponding to the node. A set of software components obtains the data corresponding to the nodes using the references included in the data array. [0008] United States Patent Application No. 20040028049 describes a method for communicating at least part of a structure of a document described by a hierarchical representation. The method identifies the hierarchical representation (eg. the tree structure) of the document. The identification is preferably performed using XML tags. The representation is then packetized into a plurality of data packets. At least one link is then created between a pair of the packets, the link acting to represent an interconnection between corresponding components (eg. structure and content) of the representation. The packets are then formed into a stream for communication. The links maintain the hierarchical representation within the packets. [0009] In the above conventional methods, however, a document is not fully decomposed into structure, labels, values and content type such that each element is independent of the others (for example, where the structure is independent of labels). Hence, each of such elements (structure, label etc) cannot be re-used independently to construct other tree-structure based documents. SUMMARY [0010] According to an aspect of the invention, a method of representing tree-structure based data comprises the steps of uncomposing tree-structure based data into a plurality of elements, the plurality of elements being of different types, storing the elements in a set, the set containing one or more of each element type, and storing one or more logical compositions with the set. Each logical composition specifying at least one of each element type. Each logical composition is reducible to a combination of specific elements of each element type representing a specific instance of tree-structure based data. [0011] According to a further aspect of the invention, a method of composing tree-structure based data comprises the steps of receiving a data set, the data set comprising at least one logical composition and at least one element of each of a plurality of element types, selecting one element of each of the plurality of element types, in accordance with the at least one logical composition, and transforming the selected elements into a pre-determined tree-structure format. [0012] According to a further aspect of the invention, a computer readable storage medium has stored therein computer executable code operable to, when executed, cause a computer to uncompose tree-structure based data into a plurality of elements, the plurality of elements being of different types, store the elements in a set, the set containing one or more of each element type, and store one or more logical compositions with the set. Each logical composition specifies at least one of each element type. Each logical composition is reducible to a combination of specific elements of each element type representing a specific instance of tree-structure based data. [0013] According to a further aspect of the invention, a computer readable storage medium has stored therein computer executable code operable to, when executed, cause a computer to receive a data set, the data set comprising at least one logical composition and at least one element of each of a plurality of element types, select one element of each of the plurality of element types, in accordance with the at least one logical composition, and transform the selected elements into a pre-determined tree-structure format. BRIEF DESCRIPTION OF THE DRAWINGS [0014] One or more embodiments of the present invention will now be described with reference to the drawings, in which: [0015] FIG. 1 shows a tree structure of exemplary XML content. [0016] FIG. 2 is a flow chart illustrating the process of converting a tree-based document to SLVC representation. [0017] FIG. 3 is a flow chart illustrating the process of obtaining a Parent-Child Relationship Map. [0018] FIG. 4 is a flow chart illustrating the process of obtaining a Parent-Child ID Map. [0019] FIG. 5 shows a tree in second form. [0020] FIG. 6 shows an exemplary object tree. [0021] FIG. 7 is a flow chart illustrating the process of converting an object tree to SLVC representation. [0022] FIG. 8 is a flow chart illustrating the process of converting an SLVC representation to a tree-based structure document. [0023] FIG. 9 is a flow chart illustrating the process of obtaining a breadth-first to depth-first node mapping. [0024] FIG. 10 is a flow chart illustrating the process of converting an SLVC representation to an object tree. [0025] FIG. 11 is a schematic diagram of a computer system embodying the disclosed invention. DETAILED DESCRIPTION [0026] Method, system and computer program products for representing tree-structure based documents and object trees are described. In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific exemplary embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be utilized, and logical, mechanical, and other changes may be made without departing from the spirit or scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims. [0027] According to aspects of the disclosed invention, tree-based documents and object trees are deconstructed into four elements. The four elements, hereinafter referred to as SLVC, are: Structure (S) Labels (L) Values (V) Content Type or Object Type (C) [0032] Each SLVC element is described with reference to Table 1, which shows an exemplary piece of XML content. [0000] TABLE 1 school.xml <School>  <Student id=“studentId1”>   <name>Peter</name>   <standard>7</standard>   <rank>15</rank>   <aggregate>72</aggregate>  </Student> </School> Structure (S) [0033] The tree structure of the content of table 1 is shown in FIG. 1 . The tree structure can be uniquely represented by a structure code using an encoding method such as the prime number encoding method described in co-pending U.S. application Ser. No. ______ [IBM Docket No. IN920060038US1], and co-pending U.S. application Ser. No. ______ [IBM Docket No. IN920060037US1], which are incorporated herein in their entirety by reference. The structure code of the tree structure representing the XML content of table 1 is: 8270262 Labels (L) [0034] The labels of the XML content of table 1 are the names of the elements and attributes. The labels are listed below and ordered in the sequence of node IDs of the tree: Labels={School, Student, id, name, standard, rank, aggregate, #text, #text, #text, #text} Values (V) [0036] The values are the data values contained in the document. For the content of Table 1, the values are: Values={studentId1, Peter, 7, 15, 72} [0038] The values are associated with the leaf nodes of the tree. Content (C) [0039] Content type is typically user specified. The content of Table 1 can be represented for example by “text/xml”. [0040] It should be understood that while the content shown in Table 1 is XML content, any tree-structure based document or object can be deconstructed into the above four elements. Examples of other content types are “text/delimited”, “text/namevalue”, “text/fixedwidth”, and the like. Also object tree such as a Service Data Object (SDO), java object trees, and the like can also be deconstructed into SLVC elements, the only difference being that the content type is replaced by object type. Composite Tree Data Type [0041] SLVC representation of tree-structure based documents and object trees to obtain a composite tree data type (CTDT) stores SLVC elements in an uncomposed form from which one or more documents/objects may be composed. Composition from SLVC elements can be performed on the fly. The uncomposed form is document/object neutral. A CTDT stores SLVC elements together with a set of compositions which map a combination of SLVC elements to a particular document/object. [0042] A CTDT represents a tree-structure based document/object in an uncomposed format, such as a collection of SLVC values along with a collection of logical compositions. For example, a CTDT can be logically represented as shown in table 2: [0000] TABLE 2 CTDT Construct Collection of Logical Compositions (Compositions) Collection of Structures (S) Collection of Labels (L) Collection of Values (V) Collection of Content/Object Types (C) [0043] The structures of CTDTs are the structure codes of the contents when represented as trees. An exemplary CTDT is shown in table 3: [0000] TABLE 3 Exemplary CTDT Compositions = {L 1 V 1 C 1 *S, V 1 C 1 *S*L, S 2 L 2 V 1 C 1 } S = {S 1 , S 2 } L = {L 1 , L 2 } V = {V 1 , V 2 } C = {C 1 , C 2 } [0044] The first composition L 1 V 1 C 1 *S resolves to {S 1 L 1 V 1 C 1 , S 2 L 1 V 1 C 1 }. [0045] The second composition V 1 C 1 *S*L resolves to {S 1 L 1 V 1 C 1 , S 1 L 2 V 1 C 1 , S 2 L 1 V 1 C 1 , S 2 L 2 V 1 C 1 }. [0046] The third composition S 2 L 2 V 1 C 1 resolves directly to S 2 L 2 V 1 C 1 . [0047] A CTDT may be constructed from raw SLVC values, from a document or part thereof, or from an object tree, or from a combination of one or more of the above. For example, the Structure (S) may be obtained from a document, the Labels (L) from an object tree, and the Values (V) may be set directly. The SLVC format of a CTDT is independent of the format of the actual tree structure. The actual tree structure may be for example XML, SDO or java objects, but are represented uniformly in SLVC format in a CTDT. [0048] A CTDT may comprise a collection of each SLVC. For example, a CTDT may have 5 structures, 10 sets of labels, 50 sets of values, and 7 content types. An actual document or object tree is composed by combining a number of these elements. CTDT Construction Document to SLVC Conversion [0049] Construction of a CTDT from a tree-structure based document takes as input a tree structure-based document, the content-type of the document, and any meta-data required by a transformer to transform the document to a tree structure. [0050] The input tree may be a tree with leaf attribute nodes, leaf text nodes, element nodes, or a combination of such nodes. A leaf attribute node is similar to an XML attribute. A leaf text node is similar to an XML #text node when it is parsed by a DOM parser. Nodes which are neither attribute nor #text nodes are element nodes. Element nodes containing values are the parents of #text nodes. Element nodes which contain values (which are parent of #text nodes) are termed value element nodes. The element nodes which do not contain values are termed object nodes. Hence, object nodes are those nodes which are neither attribute nodes, #text nodes, nor parent of #text nodes. [0051] Referring to the tree of FIG. 1 , node 3 is an attribute node, nodes 8 to 11 are text nodes (representing element values and henceforth represented as #text), and nodes 4 to 7 are value element nodes. Leaf attribute nodes have specific names, which may correspond, for example, to an attribute name in XML. In the exemplary XML content of FIG. 1 , node 3 for example has the name “id”. A leaf text node has a general name “#text”, and identification of a particular leaf text node instead refers to the parent element node of the particular leaf text node. A tree structure containing #text nodes is referred to as a tree in second form. Conversely, a tree structure in which no #text nodes are present is referred to as a tree in first form. A CTDT represents the tree structure of documents in the second form. The second form has the advantage that it can uniquely represent the structure of tree-based documents and objects which have two types of nodes:attribute nodes and element nodes (an XML document is an example of this) [0052] The conversion of a tree-structure based document to an SLVC representation is described with reference to the flow chart of FIG. 2 . [0053] At block B 01 , the document is parsed into tokens based on a predetermined separator. Depending on the document format, it may be necessary to first modify the document to ensure it can be properly parsed into tokens. Tokens parsed from a document indicate the type of node (object, attribute, or value element nodes) represented by the token. Object tokens contain both the start and the end of object indicators (for an XML document an XML fragment root node is an object token), and indicate whether the object token represents a start or end of an object. Node names are identifiable from object, attribute, or value element tokens, and node values should be determinable from attribute and value element tokens. The sequence of tokens, except of object tokens representing end object indicators, obtained from parsing a document follow a depth first sequence of tree traversal. At block B 02 , a token list is generated by the parser. The sequence of the tokens is the sequence in which the tokens are visited in the document. [0054] Most popular tree-structure based documents may be parsed, or modified to be parsed, to obtain tokens as described above. Parsing for four different document formats is described: XML Document Format [0055] Table 4 shows an exemplary XML document: [0000] TABLE 4 Exemplary XML document <Student id=“studentId1”>  <Address>   <houseNumber>17C</houseNumber>   <street>Green Avenue</street>   <postalCode>890015</postalCode>  </Address>  <ExamResult>   <courseId>MA0012</courseId>   <marks>75</marks>  </ExamResult> </Student> [0056] An XML document may be parsed/tokenized based on angle brackets and by removing whitespaces. A resulting token table listing the token names obtained from parsing the XML document of Table 4 is: [0000] Token Names Token Positions s:Student 1 @id 2 s:Address 3 houseNumber 4 Street 5 postalCode 6 e:Address 7 s:ExamResult 8 courseId 9 Marks 10 e:ExamResult 11 e:Student 12 [0057] An “s” prefix indicates the start of an object, whilst an “e” prefix represents the end of an object. An “@” prefix indicates an attribute node. The order of the tokens, with the exception of end objects indicated with the “e” prefix, is a depth-first traversal order of the XML document of Table 4. [0058] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 Name-Value Document Format [0059] Table 5 shows an exemplary Name-Value document: [0000] TABLE 5 Exemplary Name-Value document StartBO:Student  @id=studentId1  StartBO:Address   houseNumber=17C   street=GreenAvenue   postalCode=890015  EndBO:Address  StartBO:ExamResult   courseId=MA0012   marks=75  EndBO:ExamResult EndBO:Student [0060] A Name-Value document may be parsed/tokenized based on newline/whitespace characters. A resulting token table listing the token names obtained from parsing the Name-Value document of Table 5 is: [0000] Token Token Names Positions s:Student 1 @id 2 s:Address 3 houseNumber 4 street 5 postalCode 6 e:Address 7 s:ExamResult 8 courseId 9 marks 10 e:ExamResult 11 e:Student 12 [0061] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 Delimited Document Format [0062] Table 6 shows an exemplary delimited document: [0000] TABLE 6 Exemplary Delimited document StartBO:Student~@studentId1~StartBO:Address~17C~Green Avenue~890015~EndBO:Address~ StartBO:ExamResult~MA0012~75~EndBO:ExamResult~EndBO:Student [0063] A delimited document may be parsed/tokenized based on the delimiter, which in the case of the delimited document shown in Table 6, is the tilde ‘˜’. A resulting token table listing the token names obtained from parsing the delimited document of Table 6 is: [0000] Token Names Token Positions s:Student 1 @prop1 2 s:Address 3 Prop1 4 Prop2 5 Prop3 6 e:Address 7 s:ExamResult 8 Prop1 9 Prop2 10 e:ExamResult 11 e:Student 12 where prop1, prop2 and prop3 are arbitrarily assigned token names. [0064] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 Fixed Width Document Format (20 Characters Fixed Width with ‘#’ as Padding) [0065] Table 7 shows an exemplary delimited document: [0000] TABLE 7 Exemplary Fixed Width document StartBO:Student#####@studentId1#########@studentId1#####StartBO:Address#####17C## ############### Green Avenue########890015##############EndBO:Address#######StartBO:ExamResult##MA 0012############## 75##################EndBO:ExamResult########EndBO:Student####### [0066] A fixed width document may be parsed/tokenized based on the fixed length tokens (in this case 20) and removing the padding characters. A resulting token table listing the token names obtained from parsing the fixed width document of Table 7 is: [0000] Token Names Token Positions s:Student 1 @prop1 2 s:Address 3 prop1 4 prop2 5 prop3 6 e:Address 7 s:ExamResult 8 prop1 9 prop2 10 e:ExamResult 11 e:Student 12 where prop1, prop2 and prop3 are arbitrarily assigned token names. [0067] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 [0068] Once documents are reduced to respective token lists/tables as shown above, the documents become content-type neutral. This uniformity enables application of computational techniques in a content-type neutral manner. [0069] Returning to FIG. 2 at block B 03 , once a document has been parsed to obtain a token list, the tokens are represented using nested parenthesis notation. Representation of the tokens in nested parenthesis notation is described with reference to the exemplary token list/table of Table 8: [0000] TABLE 8 Exemplary token table Token Names s:Student @id s:Address houseNumber street postalCode e:Address s:ExamResult courseId marks e:ExamResult e:Student [0070] The nested parenthesis syntax is arrived at from the tokens such that a start object is assigned a begin parenthesis “(”, an end object is assigned an end parenthesis “)”, and an attribute or value element is assigned a begin parenthesis followed by an end parenthesis “( )”. The parenthesis are assigned natural number values sequentially starting from 1 and an end parenthesis is assigned the negative of the begin parenthesis value. [0071] Applying the above rules to the exemplary token table of Table 8, obtains a nested notation as follows: [0000] Token Nested Names Parenthesis Values s:Student (   1 @id ( ) 2 −2 s:Address (   3 houseNumber ( ) 4 −4 street ( ) 5 −5 postalCode ( ) 6 −6 e:Address ) −3 s:ExamResult (   7 courseId ( ) 8 −8 marks ( ) 9 −9 e:ExamResult ) −7 e:Student ) −1 [0072] Token labels may be derived from the nested notation. Token labels are obtained by removing the end of object tokens, and replacing the start of object indicators “s:” with “o:” to indicate that these tokens are objects. Further, the values in the above nested notation are used as node numbers. The token label table obtained in this manner is as follows: [0000] Node Token Labels Numbers s:Student 1 @id 2 o:Address 3 houseNumber 4 street 5 postalCode 6 o:ExamResult 7 courseId 8 marks 9 [0073] The “o:” prefix indicates that a token is an object, and the “@” prefix indicates that a token is an attribute node. [0074] Token values are retained in the same form in which they were initially obtained by the parser, with the exception that the token positions are replaced with node numbers of the same values. The token value table is hence defined as follows: [0000] Token Values Node Numbers studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 [0075] The above node numbers are consecutive in a depth-first order of tree traversal. [0076] At block B 04 , a nested parenthesis form of the tree is obtained from the above nested notation. The nested parenthesis form is the sequence of values assigned to each parenthesis, namely: 1, 2, −2, 3, 4, −4, 5, −5, 6, −6, −3, 7, 8, −8, 9, −9, −7, −1 [0078] The nested parenthesis form represents the node IDs of the tree of FIG. 1 in depth-first tree traversal order. At step B 05 , a Parent-Child Relationship map is obtained from the nested parenthesis form. The process of obtaining the Parent-Child Relationship map is described with reference to the flow chart of FIG. 3 . [0079] At block H 01 , the sequence of numbers represented by the nested parenthesis form is traversed from left to right until a negative number is encountered. The sequence traversed is noted. For the above nested parenthesis form, the traversal is: 1, 2 [0081] At block H 02 , when a negative number is encountered (i.e. “−2”), the traversed sequence is copied as a new row of a growing list. The rows of the list at this stage are hence: 1, 2 [0083] At blocks H 02 and H 03 , traversal is again performed from left to right but skipping the pair of numbers for which a negative number was encountered in block H 02 . That is, the sequence traversed is: 1, 3, 4 [0085] The numbers “2” and “−2” are skipped, as they are the pair of numbers corresponding to the negative number previously encountered (i.e. “−2). The above traversed sequence is noted, and added as a new row to the growing list: 1, 2 1, 3, 4 [0088] The process at block H 03 is repeated until traversal of the sequence is completed. The resultant list is: [0000] 1, 2 1, 3, 4 1, 3, 5 1, 3, 6 1, 7, 8 1, 7, 9 [0089] At block H 04 , the Parent-Child Relationship map is created from the list. The list is read such that a first number to the left or a second number is a parent node of the second number. Hence, from the first row, node 1 is the parent of node 2 . From the second row, node 1 is the parent of node 3 , and node 3 is the parent of node 4 . In this manner, the Parent-Child Relationship map obtained is: [0000] Parent-Child Relationship map Parent Node Number Child Node Numbers 1 2, 3, 7 3 4, 5, 6 7 8, 9 [0090] At block B 06 , the Parent-Child Relationship map is used to map the depth-first ordered node numbers to breadth-first order. The child node numbers are obtained from the Parent-Child Relationship map: 2, 3, 7, 4, 5, 6, 8, 9 [0092] The first node is prefixed to the sequence of child nodes: 1, 2, 3, 7, 4, 5, 6, 8, 9 [0094] The above sequence represents the breadth-first order of nodes. Adding the above sequence of numbers as a row, adjacent to a row containing the depth-first order of nodes provides the depth-first to breadth-first mapping of nodes: [0000] Depth-first to Breadth-first mapping Depth-First 1 2 3 4 5 6 7 8 9 Breadth-First 1 2 3 5 6 7 4 8 9 [0095] The depth-first to breadth-first mapping and the Parent-Child Relationship map are then used to obtain a Parent-Child ID Map at block B 07 . The process of obtaining the Parent-Child ID map is described with reference to the flow chart of FIG. 4 . [0096] At block I 01 , the depth-first ordered Parent-Child Relationship map is converted to a breadth-first orders using the Depth-first to Breadth-first mapping. The converted Parent-Child Relationship map is: [0000] Parent-Child Relationship Map (Breadth-first) Parent Node Number Child Node Numbers 1 2, 3, 4 3 5, 6, 7 4 8, 9 [0097] At block I 02 , an empty Parent-Child ID Map is then populated by filing in the child row with a sequence of numbers beginning from 2: [0000] Parent-Child ID Map Parent Node ID Child Node ID 2 3 4 5 6 7 8 9 [0098] At block I 03 , the parent row of the Parent-Child ID Map is populated with the node IDs of the corresponding parent node, referring to the breadth-first Parent-Child Relationship map derived at block I 02 . The resultant Parent-Child ID Map is: [0000] Parent-Child ID Map Parent Node ID 1 1 1 3 3 3 4 4 Child Node ID 2 3 4 5 6 7 8 9 [0099] The node numbers of the Parent-Child ID map are hence breadth-first ordered node numbers. [0100] The depth-first to breadth-first mapping is further used to arrange the Token Labels table and the Token Values table from a depth-first ordered sequence to a breadth-first ordered sequence (block B 08 ). The resultant rearranged tables are: [0000] Token Labels Node Token Labels Numbers o:Student 1 @id 2 o:Address 3 oExamResult 4 houseNumber 5 Street 6 postalCode 7 courseId 8 marks 9 [0101] The o: prefix indicates that the token is an object, and the @ prefix indicates that the token is an attribute node [0000] Token Values Token Values Node Numbers studentId1 2 17C 5 Green Avenue 6 890015 7 MA0012 8 75 9 [0102] From the rearranged Token Labels table and Token Values table, a token can be differentiated as being an object, value element, or attribute. The tokens in the Token Values table which are not attributes are value elements. Node 2 is an attribute token. The remaining nodes, nodes 5 , 6 , 7 , 8 , and 9 , are value element nodes. The tree represented by the above tables is converted to its second form by adding #text nodes to the value element nodes (block B 09 ). [0103] Conversion of the tree to its second form involves determining the number of value element nodes from the token value list and the last node ID of the tree in first form. The number of value elements for the above tree is 5, and the last node ID is 9. A sequence of numbers equal to the number of value elements starting from the next number after the last node ID is then generated. A sequence of 5 numbers beginning from 10 is hence generated, namely 10, 11, 12, 13, and 14. [0104] The Parent-Child ID Map is then modified by extending the number of columns by the number of numbers in the sequence: [0000] Parent-Child Id Map (modified) Parent 1 1 1 3 3 3 4 4 — — — — — Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0105] The incomplete parent row of the modified Parent-Child ID Map is then filled in consecutively with the node numbers of the nodes which are value elements. Namely, 5, 6, 7, 8, and 9: [0000] Parent-Child ID Map (modified) Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0106] #text nodes are added to the Token Labels table corresponding to the newly added node numbers: [0000] Node Token Labels Numbers o:Student 1 @id 2 o:Address 3 o:ExamResult 4 houseNumber 5 Street 6 postalCode 7 courseId 8 marks 9 #text 10 #text 11 #text 12 #text 13 #text 14 [0107] Then, referring to the Parent-Child ID Map, the Token Values table is modified such that the node numbers in the Token Values table are replaced with the newly generated node numbers of the #text node: [0000] Token Values Node Numbers (old) Node Numbers (new) studentId1 2 2 17C 5 10 Green Avenue 6 11 890015 7 12 MA0012 8 13 75 9 14 [0108] In this manner, the tree is converted to its second form, with #text nodes. The tree is shown in FIG. 5 . [0109] At block B 10 , the structure code is obtained from the Parent-Child ID Map according to the computation disclosed in U.S. application Ser. No. ______ [IBM Docket No. IN920060037US1], incorporated herein by reference. The structure code is 52055003000. [0110] The structure code obtained from the above computation represents the tree structure uniquely. However to overcome certain special cases where two semantically different documents have the same tree structure, node Ids of special nodes (if any) need to be appended to the structure code obtained in the previous step. This will give the final structure code. These special cases are disclosed in U.S. application Ser. No. ______[IBM Docket No. IN920060037US1], with reference to XML documents, which are equally applicable for other tree based documents. [0111] From the above, the structure code, labels, and values of the tree are obtained. Namely: S=52055003000 L={Student, id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks, #text, #text, #text, #text, #text} V={studentId1, 17C, Green Avenue, 890015, MA0012, 75}. C=The content is as specified by the user, and is text/xml for example. [0116] At block B 11 , the above SLVC elements are compiled and the document is hence represented in SLVC representation. Object Tree to SLVC [0117] Construction of a CTDT from an object tree takes as input the object, the object-type of the object, and configuration data for data transformation. [0118] FIG. 6 shows an exemplary object tree. The object tree is in first form, meaning that no #text nodes are present. Attribute nodes in the object tree are identified with a “@” prefix before the attribute name. Conversion of the object tree to SLVC representation is described with reference to the flow chart of FIG. 7 . [0119] At block E 01 , the object tree is traversed in breadth-first order, and node IDs assigned to each node in this order. In FIG. 6 , node IDs are shown inside each node. At block E 02 , a Parent-Child ID Map of the object tree is created. The Parent-Child ID Map can be created directly from the object tree as parent-child relationships between nodes are explicitly apparent from the object tree. The Parent-Child ID Map for the object tree of FIG. 6 is: [0000] Parent-Child ID Map Parent Node Id 1 1 1 3 3 3 4 4 Child Node Id 2 3 4 5 6 7 8 9 [0120] At block E 03 , a label list in which the position of the nodes in the list correspond to the node ID of the object tree in breadth-first order is created. The label list is: Labels={Student, #id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks} [0122] At block E 04 , the leaf nodes of the object tree are determined from the Parent-Child ID Map generated at block E 02 . The leaf nodes are obtained from the Parent-Child ID Map as follows. The leaf nodes are those nodes which are present in the child row of the Parent-Child Id Map and not present in the parent row of the Parent-Child Id Map. Leaf nodes={2, 5, 6, 7, 8, 9} [0124] At block E 05 , the values of the leaf nodes are obtained from the tree: Values={studentId1, 17C, Green Avenue, 890015, MA0012, 75} [0126] At block E 06 , the attribute nodes of the tree are determined from the label list obtained at block E 03 . As previously described, the attribute nodes are the nodes whose labels bear a predetermined label. In the present example, nodes prefixed with “@” are attribute nodes. A list of attribute nodes is: Attribute Nodes={2} [0128] At block E 07 , the value element nodes of the tree are determined from the leaf node list. The value element nodes are the nodes of the leaf node list which are not attribute nodes. The list of value element nodes is hence: Value Element Nodes={5, 6, 7, 8, 9} [0130] It should be noted that for a tree in second form, the value element nodes are the parent nodes of #text nodes. [0131] The tree is converted to second from at block E 08 by adding #text nodes, in the manner as described previously with reference to conversion of a document to SLVC representation. The Parent-Child ID Map of the object tree after conversion to second form is: [0000] Parent-Child ID Map (second form) Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0132] And the labels list is: Labels (second form)={Student, #id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks, #text, #text, #text, #text, #text} [0134] It should be understood that if the input tree was already in second form, the conversion performed at block E 08 may be skipped. [0135] At block E 09 , the structure code is determined from the Parent-Child ID Map according to the computation as described previously with reference to conversion of a document to SLVC representation. The structure code is: 52055003000. [0136] In the above manner, all SLVC elements are determined. Specifically: S=52055003000 L={Student, #id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks, #text, #text, #text, #text} V={studentId1, 17C, Green Avenue, 890015, MA0012, 75} C=commonj.sdo.DataObject (specified by the user) [0141] At block E 10 , the SLVC elements are compiled and the object tree is hence represented in SLVC representation. [0000] Conversion from CTDT SLVC to Document Conversion [0142] Conversion of a CTDT from an SLVC representation to a tree-structure based document takes as input the SLVC representation, and any configuration data that may be required for data transformation. Conversion of a CTDT from an SLVC representation to a tree-structure based document is described with reference to the exemplary SLVC representation of table 7 and the flow chart of FIG. 8 . [0000] TABLE 7 Exemplary SLVC data S = 52055003000 L = {Student, id, Address, ExamResult, houseNumber, street, PostalCode, courseID, marks, #text, #text, #text, #text, #text,} V = {studentID1, 17C, Green Avenue, 890015, MA0012, 75} C = text/xml (specified by user) [0143] At block F 01 , a Parent-Child ID Map is obtained from the structure code of the SLVC representation. The Parent-Child ID Map is obtained from the structure code using the technique described in co-pending U.S. application Ser. No. ______[IBM Docket No. IN920060037US1]. [0144] The Parent-Child ID Map is: [0000] Parent-Child ID Map Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id where the node IDs are breadth-first ordered. [0145] In cases where the structure code has special nodes appended, as described in co-pending U.S. application Ser. No. ______ [IBM Docket No. IN920060038US1], the above computation applies to the first part of the structure code which is obtained by separating it from the appended special nodes. [0146] At block F 02 , from the label list L, the node IDs of the #text nodes are identified. The node IDs are: #text node IDs={10, 11, 12, 13, 14} [0148] At block F 03 , the Parent-Child ID Map, which is in the second form, is converted to the first form by removing the #text nodes from the map and transforming the Parent-Child ID Map. The columns of the Parent-Child ID Map containing the #text node IDs are removed. The Parent-Child ID Map in first form is: [0000] Parent-Child ID Map (first form) Parent Node Id 1 1 1 3 3 3 4 4 Child Node Id 2 3 4 5 6 7 8 9 [0149] At block F 04 , a Parent-Child Relationship Map is derived from the Parent-Child ID Map (first form). The Parent-Child ID Map gives the mapping between parent nodes and child nodes. When a parent node has multiple child nodes, the relationships are repeated. If the Parent-Child mapping are not repeated, and each parent node is associated with all its children, the Parent-Child Relationship Map is obtained. The Parent-Child Relationship Map derived in this manner is in breath-first order and is: [0000] Parent-Child Relationship Map (breadth-first) Parent Node Id Child Node Ids 1 2, 3, 4 3 5, 6, 7 4 8, 9 [0150] At block F 05 , a breadth-first to depth-first node mapping is obtained from the Parent-Child ID Map (first form). [0151] The process of obtaining the breadth-first to depth-first node mapping is described with reference to the flow chart of FIG. 9 , and the Parent-Child Relationship map (breadth-first). [0000] Parent-Child Relationship Map (breadth-first) Parent Node Number Child Node Numbers 1 2, 3, 4 3 5, 6, 7 4 8, 9 [0152] At block K 01 , the key and value of the lower most row of the Parent-Child Relationship map (breadth-first) is obtained: 4: 8, 9 [0154] At block K 02 , the key obtained at block K 01 is searched for in the value column of the Parent-Child Relationship map (breadth-first). The values obtained at block K 01 are appended to the values of the row containing the key in its value column, and the lower most row is deleted. [0000] Parent-Child Relationship map (modified) Parent Node Number Child Node Numbers 1 2, 3, 4, 8, 9 3 5, 6, 7 [0155] Block K 02 is repeated until the table has only one row: [0000] Parent-Child Relationship map (modified) Parent Node Number Child Node Numbers 1 2, 3, 5, 6, 7, 4, 8, 9 [0156] At block K 03 , the key and values of the modified Parent-Child Relationship map are concatenated to form a row: [0000] 1, 2, 3, 5, 6, 7, 4, 8, 9 [0157] The breadth-first to depth-first map is created from the above row, and a new row containing a sequence of numbers representing the depth-first order of nodes: [0000] Breadth-First to Depth-First node mapping Breadth-First 1, 2, 3, 5, 6, 7, 4, 8, 9 Depth-First 1, 2, 3, 4, 5, 6, 7, 8, 9 [0158] The above map may be sorted by Breadth-first order to facilitate easier reference: [0000] Breadth-first to Depth-first node mapping Breadth-First 1 2 3 4 5 6 7 8 9 Depth-First 1 2 3 7 4 5 6 8 9 [0159] At block F 06 , the Parent-Child Relationship Map in breadth-first order is transformed to depth-first order using the breadth-first to depth-first node mapping. The transformed Parent-Child Relationship Map in depth-first order is: [0000] Parent-Child Relationship Map (depth-first) Parent Node Id Child Node Ids 1 2, 3, 7 3 4, 5, 6 7 8, 9 [0160] At block F 07 , the labels from the SLVC representation are separated into a Token Name list without the #text nodes. The Token Name list is: Token Name list (breadth-first)={Student, ID, Address, ExamResult, houseNumber, street, postalCode, courseID, marks} [0162] The position of the nodes corresponds to the node IDs of the tree. [0163] At block F 08 , the token name list is modified to mark the attribute nodes with a predetermined identifier. The attribute nodes can be identified by identifying all leaf nodes which are not #text nodes. From the Parent-Child Id Map (second form) the leaf nodes are those nodes which are present in the child row but not in the parent row of the Parent-Child ID map. Therefore the leaf nodes are: Leaf nodes={2, 10, 11, 12, 13, 14} [0165] Any leaf node whose parent has a grandchild is an attribute node if it is not a special node. Since node Ids of special nodes are appended with the structure code, it is known which nodes are special nodes. Any leaf node which is not an attribute node is a #text node. [0166] Special nodes are described in further detail in co-pending U.S. application Ser. No. ______ [IBM Docket No. IN920060038US1] with reference to XML data, but is equally applicable to other tree-based data. Knowing the parent-child hierarchy of node Ids from the Parent-Child ID map (second form), the #text nodes are determined as described above. The #text nodes are hence: #text nodes={10, 11, 12,13, 14} [0168] The attribute node is hence: Attribute nodes={2} [0170] In the present example, the attribute nodes in the Token Name list are marked with an ‘@’ prefix. The Token list is hence: Token Name list (breadth-first)={Student, @id, Address, ExamResult, houseNumber, street, postalCode, courseID, marks} [0172] At block F 09 , the object nodes are identified from the structure code, and identified in the Token Name list. The object nodes are identified as nodes which are neither attribute nodes, value element nodes, nor #text nodes. The #text nodes are already known. The value element nodes are the parent nodes of the #text nodes and are hence: Value Element nodes={5, 6, 7, 8, 9} [0174] The object nodes are hence: Object nodes={1, 3, 4} [0176] In the present example, the object nodes are marked with an “o:” prefix in the Token Names list. The Token list is hence: [0177] Token Name list (breadth-first)={o:Student, @id, o:Address, o:ExamResult, houseNumber, street, postalCode, courseID, marks} [0178] At block, F 10 the node IDs of the nodes containing values (breadth-first order) are obtained. This is a combination of attribute nodes and value element nodes. The node IDs sorted in ascending order are: Nodes containing values (breadth-first)={2, 5, 6, 7, 8, 9} [0180] At block F 11 , the Token Name list is arranged in depth-first order using the Breadth-first to Depth-first mapping previously determined. Token Name list (depth-first)={o:Student, @id, o:Address, houseNumber, street, postalCode, o:ExamResult, courseID, marks} [0182] At block F 12 , the list of nodes containing values obtained at block F 10 is transformed from a listing of breadth-first IDs to a listing of depth-first IDs using the breadth-first to depth-first mapping: Nodes containing values (depth-first)={2, 4, 5, 6, 8, 9} [0184] At block F 13 , the child nodes for each object node in the Token Name list (depth-first) are identified using the depth-first Parent-Child Relationship map obtained at block F 06 . An end object indicator is added to the Token Name list after the last child node of each object node. Object prefixes “o:” are replaced with an object start prefix “s:”. For example, from the Parent-Child Relationship map (depth-first), it is determined that the child nodes of the “Address” node (having node ID 3 ), are nodes 4 , 5 and 6 . The last child node of the object node “Address” is therefore node 6 , which is 3 nodes away from the object node “o:Address”. A new entry “e:Address” is therefore added to the Token Name list 3 entries from “o:Address”, and “o:Address” is renamed “s:Address”. This modification is performed for each object name in the Token Name list. [0185] The Token Name list after this process is: Token Name list (depth-first)={s:Student, #id, s:Address, houseNumber, street, postaIC ode, e:Address, s:ExamResult, courseID, marks, e:ExamResult, e:Student} [0187] At block F 14 , the node IDs in the list of nodes containing values (depth-first) is adjusted by adding to each node ID in the list, the number of end object nodes between the first node and each node, respectively. Referring, for example, to the node having node ID 8 in the list of nodes containing values (depth-first), the number of end object nodes between this node and the first node of the Token Name list is determined: [0188] The node having node ID 8 in the list of nodes containing values (depth-first) is “courseID”. [0189] The nodes between first node and the “courseID” node are: s:Student @id s:Address houseNumber street postalCode e:Address (*) s:ExamResult [0198] The number of end object nodes is 1, being the “e:Address” node. Node ID 8 in the list of nodes containing values (depth-first) is hence adjusted by adding 1, giving it an adjusted Node ID of 9. Performing this adjustment to each node in the list of node containing values (depth-first) yields an adjusted list of nodes: Nodes containing values (depth-first, adjusted)={2, 4, 5, 6, 9, 10} [0200] At block F 15 , the Token Name list, Token Value list, and list of nodes containing values is submitted to a data transformer corresponding to a data transformer appropriate for the content type specified by the SLVC representation. The data transformer hence receives as input: Token Name list (depth-first)={s:Student, @id, s:Address, houseNumber, street, postalCode, e:Address, s:ExamResult, courseId, marks, e:ExamResult, e:Student} Token Value list={studentId1, 17C, Green Avenue, 890015, MA0012, 75} Nodes containing values (depth-first, adjusted)={2, 4, 5, 6, 9, 10} [0204] From the above information, the data transformer reproduces a document (for example, an XML document). SLVC to Object Conversion [0205] Conversion of a CTDT from an SLVC representation to an object tree takes as input the SLVC representation, and any configuration data that may be required for data transformation. Conversion of a CTDT from an SLVC representation to an object tree is described with reference to the exemplary SLVC representation of table 9. and the flow chart of FIG. 10 . [0000] TABLE 7 Exemplary SLVC data S = 52055003000 L = {Student, id, Address, ExamResult, houseNumber, street, PostalCode, courseID, marks, #text, #text, #text, #text, #text,} V = {studentID1, 17C, Green Avenue, 890015, MA0012, 75} C = commonj.sdo.DataObject (specified by user) [0206] At block G 01 , a Parent-Child ID map is created from the structure code of the SLVC representation, as described in the above co-pending U.S. application Ser. No. ______ [IBM Docket No. IN920060037US1]. The Parent-Child ID map is in second form, including #text nodes: [0000] Parent-Child ID Map (breadth-first, second form) Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0207] At block G 02 , the node IDs of the #text nodes are determined from the labels list of the SLVC representation. The Node IDs are obtained from the position of the #text nodes in the labels list: The Node IDs correspond to the position indices of the #text nodes in the labels list if the position index of the first element is taken as 1. #text nodes={10, 11 12, 13, 14} [0209] At block G 03 , the #text nodes are removed from the Parent-Child ID map if the object tree to be output does not require #text nodes to be retained. Otherwise, the conversion skips to block G 04 : [0000] Parent-Child ID Map (#text nodes removed) Parent Node Id 1 1 1 3 3 3 4 4 Child Node Id 2 3 4 5 6 7 8 9 [0210] At block G 04 , the leaf nodes are determined from the Parent-Child ID map: Leaf nodes={2, 5, 6, 7, 8, 9} [0212] At block G 05 , the object nodes are determined from the Parent-Child ID map. The object nodes here are the non-leaf nodes since the tree is in first-form: Object nodes={1, 3, 4} [0214] At block G 06 , an object tree of a type specified by the object type in the SLVC representation is created. The object tree has node names as obtained from the labels list, value nodes having values corresponding to the leaf nodes, and parent-child relationship between nodes as given by the Parent-Child ID Map. [0215] The above method of converting tree-structure based documents and object trees to/from SLVC representation, may be implemented using a computer system 1200 , such as that shown in FIG. 11 wherein the processes of FIGS. 3 to 5 and 8 to 10 may be implemented as software, such as one or more application programs executable within the computer system 1200 . In particular, the steps of the described methods/processes are effected by instructions in the software that are carried out within the computer system 1200 . The instructions may be formed as one or more code modules, each for performing one or more particular tasks. The software may also be divided into two separate parts, in which a first part and the corresponding code modules performs the conversion methods and a second part and the corresponding code modules manage a user interface between the first part and the user. [0216] The software may be stored in a computer readable medium, including the storage devices described below, for example. The software is loaded into the computer system 1200 from the computer readable medium, and then executed by the computer system 1200 . A computer readable medium having such software or computer program recorded on it is a computer program product. The use of the computer program product in the computer system 1200 preferably effects an advantageous apparatus for converting tree-structure based documents and object trees to an SLVC representation, and vice versa. [0217] As seen in FIG. 11 , the computer system 1200 is formed by a computer module 1201 , input devices such as a keyboard 1202 and a mouse pointer device 1203 , and output devices including a printer 1215 , a display device 1214 and loudspeakers 1217 . An external Modulator-Demodulator (Modem) transceiver device 1216 may be used by the computer module 1201 for communicating to and from a communications network 1220 via a connection 1221 . The network 1220 may be a wide-area network (WAN), such as the Internet or a private WAN. Where the connection 1221 is a telephone line, the modem 1216 may be a traditional dial-up modem. Alternatively, where the connection 1221 is a high capacity (eg: cable) connection, the modem 1216 may be a broadband modem. A wireless modem may also be used for wireless connection to the network 1220 . [0218] The computer module 1201 typically includes at least one processor unit 1205 , and a memory unit 1206 for example formed from semiconductor random access memory (RAM) and read only memory (ROM). The module 1201 also includes an number of input/output (I/O) interfaces including an audio-video interface 1207 that couples to the video display 1214 and loudspeakers 1217 , an I/O interface 1213 for the keyboard 1202 and mouse 1203 and optionally a joystick (not illustrated), and an interface 1208 for the external modem 1216 and printer 1215 . In some implementations, the modem 1216 may be incorporated within the computer module 1201 , for example within the interface 1208 . The computer module 1201 also has a local network interface 1211 which, via a connection 1223 , permits coupling of the computer system 1200 to a local computer network 1222 , known as a Local Area Network (LAN). As also illustrated, the local network 1222 may also couple to the wide network 1220 via a connection 1224 , which would typically include a so-called firewall device or similar functionality. The interface 1211 may be formed by an Ethernet™ circuit card, a wireless Bluetooth™ or an IEEE 802.11 wireless arrangement. [0219] The interfaces 1208 and 1213 may afford both serial and parallel connectivity, the former typically being implemented according to the Universal Serial Bus (USB) standards and having corresponding USB connectors (not illustrated). Storage devices 1209 are provided and typically include a hard disk drive (HDD) 1210 . Other devices such as a floppy disk drive and a magnetic tape drive (not illustrated) may also be used. An optical disk drive 1212 is typically provided to act as a non-volatile source of data. Portable memory devices, such optical disks (eg: CD-ROM, DVD), USB-RAM, and floppy disks for example may then be used as appropriate sources of data to the system 1200 . [0220] The components 1205 , to 1213 of the computer module 1201 typically communicate via an interconnected bus 1204 and in a manner which results in a conventional mode of operation of the computer system 1200 known to those in the relevant art. Examples of computers on which the described arrangements can be practised include IBM-PC and compatibles, Sun Sparcstations, Apple Mac™ or alike computer systems evolved therefrom. [0221] Typically, the application programs discussed above are resident on the hard disk drive 1210 and read and controlled in execution by the processor 1205 . Intermediate storage of such programs and any data fetched from the networks 1220 and 1222 may be accomplished using the semiconductor memory 1206 , possibly in concert with the hard disk drive 1210 . In some instances, the application programs may be supplied to the user encoded on one or more CD-ROM and read via the corresponding drive 1212 , or alternatively may be read by the user from the networks 1220 or 1222 . Still further, the software can also be loaded into the computer system 1200 from other computer readable media. Computer readable media refers to any storage medium that participates in providing instructions and/or data to the computer system 1200 for execution and/or processing. Examples of such media include floppy disks, magnetic tape, CD-ROM, a hard disk drive, a ROM or integrated circuit, a magneto-optical disk, or a computer readable card such as a PCMCIA card and the like, whether or not such devices are internal or external of the computer module 1201 . Examples of computer readable transmission media that may also participate in the provision of instructions and/or data include radio or infra-red transmission channels as well as a network connection to another computer or networked device, and the Internet or Intranets including e-mail transmissions and information recorded on Websites and the like. [0222] The second part of the application programs and the corresponding code modules mentioned above may be executed to implement one or more graphical user interfaces (GUIs) to be rendered or otherwise represented upon the display 1214 . Through manipulation of the keyboard 1202 and the mouse 1203 , a user of the computer system 1200 and the application may manipulate the interface to provide controlling commands and/or input to the applications associated with the GUI(s). [0223] The method of converting tree-structure based documents and object trees to/from SLVC representation may alternatively be implemented in dedicated hardware such as one or more integrated circuits. Such dedicated hardware may include graphic processors, digital signal processors, or one or more microprocessors and associated memories. [0224] The foregoing describes only some embodiments of the present invention, and modifications and/or changes can be made thereto without departing from the scope and spirit of the invention, the embodiments being illustrative and not restrictive.
A method of representing tree-structure based data. The method comprises the steps of uncomposing tree-structure based data into a plurality of elements, the plurality of elements being of different types, storing the elements in a set, the set containing one or more of each element type, and storing one or more logical compositions with the set, each logical composition specifying at least one of each element type. Each logical composition is reducible to a combination of specific elements of each element type representing a specific instance of tree-structure based data.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "TECHNICAL FIELD [0001] The present invention relates generally to data types, and in particular to a composite tree data type representing tree based documents and objects.", "BACKGROUND [0002] Tree-structured based documents and objects are popular formats for storing and exchanging data.", "XML, for example, is a tree-structure based document widely used for exchanging data, and is also becoming a data type commonly stored in databases and queried by users.", "Service Data Objects (SDO) have also become popular as an object format for data transfer in the field of integration.", "[0003] In the conventional way of representing tree-structure based documents and objects, the documents/objects are considered as a whole or a single unit.", "For example, XML content is perceived as a single entity, and the individual elements making up the XML content, such as the structure, labels, values and contents, are not looked upon or considered as separate entities.", "Such a representation encounters the disadvantages of: (a) Unnecessary repetition: if a large number of documents have many elements in common, multiple copies are still required to contain them;", "and (b) Loss of flexibility: if for example there is a need to modify the structure or content type of the document separately, the entire document needs to change.", "[0006] United States Patent Application No. 20060031233A1 describes a universal format that is used to create a type representation of XMLType instances that are generated in various ways from various sources.", "An XMLType Type Tree is represented as a hierarchy of nodes, including a leaf item node, composite item node, operator node, and aggregate node, referred to herein as an XMLType Type Tree.", "An XMLType Type Tree serves as a digest of the type structure of XMLType, no matter the source of the XMLType instance or its manner of generation, and it creates one uniform abstraction of the type structure of XMLType for the data-typing analysis of XPath and XQuery during query compile time.", "[0007] United States Patent Application No. 20020087596 describes a document written in a markup language, represented by a unique data structure.", "A virtual node tree describes the structure of the data types in the document.", "Each one of the nodes in the virtual node tree respectively corresponds to one of the data types in the document.", "A data array corresponding to each one of the nodes in the virtual node tree includes information identifying the relationship of the node to other nodes in the virtual node tree and a reference indicating the location of the data corresponding to the node.", "A set of software components obtains the data corresponding to the nodes using the references included in the data array.", "[0008] United States Patent Application No. 20040028049 describes a method for communicating at least part of a structure of a document described by a hierarchical representation.", "The method identifies the hierarchical representation (eg.", "the tree structure) of the document.", "The identification is preferably performed using XML tags.", "The representation is then packetized into a plurality of data packets.", "At least one link is then created between a pair of the packets, the link acting to represent an interconnection between corresponding components (eg.", "structure and content) of the representation.", "The packets are then formed into a stream for communication.", "The links maintain the hierarchical representation within the packets.", "[0009] In the above conventional methods, however, a document is not fully decomposed into structure, labels, values and content type such that each element is independent of the others (for example, where the structure is independent of labels).", "Hence, each of such elements (structure, label etc) cannot be re-used independently to construct other tree-structure based documents.", "SUMMARY [0010] According to an aspect of the invention, a method of representing tree-structure based data comprises the steps of uncomposing tree-structure based data into a plurality of elements, the plurality of elements being of different types, storing the elements in a set, the set containing one or more of each element type, and storing one or more logical compositions with the set.", "Each logical composition specifying at least one of each element type.", "Each logical composition is reducible to a combination of specific elements of each element type representing a specific instance of tree-structure based data.", "[0011] According to a further aspect of the invention, a method of composing tree-structure based data comprises the steps of receiving a data set, the data set comprising at least one logical composition and at least one element of each of a plurality of element types, selecting one element of each of the plurality of element types, in accordance with the at least one logical composition, and transforming the selected elements into a pre-determined tree-structure format.", "[0012] According to a further aspect of the invention, a computer readable storage medium has stored therein computer executable code operable to, when executed, cause a computer to uncompose tree-structure based data into a plurality of elements, the plurality of elements being of different types, store the elements in a set, the set containing one or more of each element type, and store one or more logical compositions with the set.", "Each logical composition specifies at least one of each element type.", "Each logical composition is reducible to a combination of specific elements of each element type representing a specific instance of tree-structure based data.", "[0013] According to a further aspect of the invention, a computer readable storage medium has stored therein computer executable code operable to, when executed, cause a computer to receive a data set, the data set comprising at least one logical composition and at least one element of each of a plurality of element types, select one element of each of the plurality of element types, in accordance with the at least one logical composition, and transform the selected elements into a pre-determined tree-structure format.", "BRIEF DESCRIPTION OF THE DRAWINGS [0014] One or more embodiments of the present invention will now be described with reference to the drawings, in which: [0015] FIG. 1 shows a tree structure of exemplary XML content.", "[0016] FIG. 2 is a flow chart illustrating the process of converting a tree-based document to SLVC representation.", "[0017] FIG. 3 is a flow chart illustrating the process of obtaining a Parent-Child Relationship Map.", "[0018] FIG. 4 is a flow chart illustrating the process of obtaining a Parent-Child ID Map.", "[0019] FIG. 5 shows a tree in second form.", "[0020] FIG. 6 shows an exemplary object tree.", "[0021] FIG. 7 is a flow chart illustrating the process of converting an object tree to SLVC representation.", "[0022] FIG. 8 is a flow chart illustrating the process of converting an SLVC representation to a tree-based structure document.", "[0023] FIG. 9 is a flow chart illustrating the process of obtaining a breadth-first to depth-first node mapping.", "[0024] FIG. 10 is a flow chart illustrating the process of converting an SLVC representation to an object tree.", "[0025] FIG. 11 is a schematic diagram of a computer system embodying the disclosed invention.", "DETAILED DESCRIPTION [0026] Method, system and computer program products for representing tree-structure based documents and object trees are described.", "In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific exemplary embodiments in which the invention may be practiced.", "These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention.", "Other embodiments may be utilized, and logical, mechanical, and other changes may be made without departing from the spirit or scope of the present invention.", "The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.", "[0027] According to aspects of the disclosed invention, tree-based documents and object trees are deconstructed into four elements.", "The four elements, hereinafter referred to as SLVC, are: Structure (S) Labels (L) Values (V) Content Type or Object Type (C) [0032] Each SLVC element is described with reference to Table 1, which shows an exemplary piece of XML content.", "[0000] TABLE 1 school.", "xml <School>", "<Student id=“studentId1”>", "<name>Peter</name>", "<standard>7</standard>", "<rank>15</rank>", "<aggregate>72</aggregate>", "</Student>", "</School>", "Structure (S) [0033] The tree structure of the content of table 1 is shown in FIG. 1 .", "The tree structure can be uniquely represented by a structure code using an encoding method such as the prime number encoding method described in co-pending U.S. application Ser.", "No. ______ [IBM Docket No. IN920060038US1], and co-pending U.S. application Ser.", "No. ______ [IBM Docket No. IN920060037US1], which are incorporated herein in their entirety by reference.", "The structure code of the tree structure representing the XML content of table 1 is: 8270262 Labels (L) [0034] The labels of the XML content of table 1 are the names of the elements and attributes.", "The labels are listed below and ordered in the sequence of node IDs of the tree: Labels={School, Student, id, name, standard, rank, aggregate, #text, #text, #text, #text} Values (V) [0036] The values are the data values contained in the document.", "For the content of Table 1, the values are: Values={studentId1, Peter, 7, 15, 72} [0038] The values are associated with the leaf nodes of the tree.", "Content (C) [0039] Content type is typically user specified.", "The content of Table 1 can be represented for example by “text/xml.”", "[0040] It should be understood that while the content shown in Table 1 is XML content, any tree-structure based document or object can be deconstructed into the above four elements.", "Examples of other content types are “text/delimited”, “text/namevalue”, “text/fixedwidth”, and the like.", "Also object tree such as a Service Data Object (SDO), java object trees, and the like can also be deconstructed into SLVC elements, the only difference being that the content type is replaced by object type.", "Composite Tree Data Type [0041] SLVC representation of tree-structure based documents and object trees to obtain a composite tree data type (CTDT) stores SLVC elements in an uncomposed form from which one or more documents/objects may be composed.", "Composition from SLVC elements can be performed on the fly.", "The uncomposed form is document/object neutral.", "A CTDT stores SLVC elements together with a set of compositions which map a combination of SLVC elements to a particular document/object.", "[0042] A CTDT represents a tree-structure based document/object in an uncomposed format, such as a collection of SLVC values along with a collection of logical compositions.", "For example, a CTDT can be logically represented as shown in table 2: [0000] TABLE 2 CTDT Construct Collection of Logical Compositions (Compositions) Collection of Structures (S) Collection of Labels (L) Collection of Values (V) Collection of Content/Object Types (C) [0043] The structures of CTDTs are the structure codes of the contents when represented as trees.", "An exemplary CTDT is shown in table 3: [0000] TABLE 3 Exemplary CTDT Compositions = {L 1 V 1 C 1 *S, V 1 C 1 *S*L, S 2 L 2 V 1 C 1 } S = {S 1 , S 2 } L = {L 1 , L 2 } V = {V 1 , V 2 } C = {C 1 , C 2 } [0044] The first composition L 1 V 1 C 1 *S resolves to {S 1 L 1 V 1 C 1 , S 2 L 1 V 1 C 1 }.", "[0045] The second composition V 1 C 1 *S*L resolves to {S 1 L 1 V 1 C 1 , S 1 L 2 V 1 C 1 , S 2 L 1 V 1 C 1 , S 2 L 2 V 1 C 1 }.", "[0046] The third composition S 2 L 2 V 1 C 1 resolves directly to S 2 L 2 V 1 C 1 .", "[0047] A CTDT may be constructed from raw SLVC values, from a document or part thereof, or from an object tree, or from a combination of one or more of the above.", "For example, the Structure (S) may be obtained from a document, the Labels (L) from an object tree, and the Values (V) may be set directly.", "The SLVC format of a CTDT is independent of the format of the actual tree structure.", "The actual tree structure may be for example XML, SDO or java objects, but are represented uniformly in SLVC format in a CTDT.", "[0048] A CTDT may comprise a collection of each SLVC.", "For example, a CTDT may have 5 structures, 10 sets of labels, 50 sets of values, and 7 content types.", "An actual document or object tree is composed by combining a number of these elements.", "CTDT Construction Document to SLVC Conversion [0049] Construction of a CTDT from a tree-structure based document takes as input a tree structure-based document, the content-type of the document, and any meta-data required by a transformer to transform the document to a tree structure.", "[0050] The input tree may be a tree with leaf attribute nodes, leaf text nodes, element nodes, or a combination of such nodes.", "A leaf attribute node is similar to an XML attribute.", "A leaf text node is similar to an XML #text node when it is parsed by a DOM parser.", "Nodes which are neither attribute nor #text nodes are element nodes.", "Element nodes containing values are the parents of #text nodes.", "Element nodes which contain values (which are parent of #text nodes) are termed value element nodes.", "The element nodes which do not contain values are termed object nodes.", "Hence, object nodes are those nodes which are neither attribute nodes, #text nodes, nor parent of #text nodes.", "[0051] Referring to the tree of FIG. 1 , node 3 is an attribute node, nodes 8 to 11 are text nodes (representing element values and henceforth represented as #text), and nodes 4 to 7 are value element nodes.", "Leaf attribute nodes have specific names, which may correspond, for example, to an attribute name in XML.", "In the exemplary XML content of FIG. 1 , node 3 for example has the name “id.”", "A leaf text node has a general name “#text”, and identification of a particular leaf text node instead refers to the parent element node of the particular leaf text node.", "A tree structure containing #text nodes is referred to as a tree in second form.", "Conversely, a tree structure in which no #text nodes are present is referred to as a tree in first form.", "A CTDT represents the tree structure of documents in the second form.", "The second form has the advantage that it can uniquely represent the structure of tree-based documents and objects which have two types of nodes:attribute nodes and element nodes (an XML document is an example of this) [0052] The conversion of a tree-structure based document to an SLVC representation is described with reference to the flow chart of FIG. 2 .", "[0053] At block B 01 , the document is parsed into tokens based on a predetermined separator.", "Depending on the document format, it may be necessary to first modify the document to ensure it can be properly parsed into tokens.", "Tokens parsed from a document indicate the type of node (object, attribute, or value element nodes) represented by the token.", "Object tokens contain both the start and the end of object indicators (for an XML document an XML fragment root node is an object token), and indicate whether the object token represents a start or end of an object.", "Node names are identifiable from object, attribute, or value element tokens, and node values should be determinable from attribute and value element tokens.", "The sequence of tokens, except of object tokens representing end object indicators, obtained from parsing a document follow a depth first sequence of tree traversal.", "At block B 02 , a token list is generated by the parser.", "The sequence of the tokens is the sequence in which the tokens are visited in the document.", "[0054] Most popular tree-structure based documents may be parsed, or modified to be parsed, to obtain tokens as described above.", "Parsing for four different document formats is described: XML Document Format [0055] Table 4 shows an exemplary XML document: [0000] TABLE 4 Exemplary XML document <Student id=“studentId1”>", "<Address>", "<houseNumber>17C</houseNumber>", "<street>Green Avenue</street>", "<postalCode>890015</postalCode>", "</Address>", "<ExamResult>", "<courseId>MA0012</courseId>", "<marks>75</marks>", "</ExamResult>", "</Student>", "[0056] An XML document may be parsed/tokenized based on angle brackets and by removing whitespaces.", "A resulting token table listing the token names obtained from parsing the XML document of Table 4 is: [0000] Token Names Token Positions s:Student 1 @id 2 s:Address 3 houseNumber 4 Street 5 postalCode 6 e:Address 7 s:ExamResult 8 courseId 9 Marks 10 e:ExamResult 11 e:Student 12 [0057] An “s”", "prefix indicates the start of an object, whilst an “e”", "prefix represents the end of an object.", "An “@”", "prefix indicates an attribute node.", "The order of the tokens, with the exception of end objects indicated with the “e”", "prefix, is a depth-first traversal order of the XML document of Table 4.", "[0058] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 Name-Value Document Format [0059] Table 5 shows an exemplary Name-Value document: [0000] TABLE 5 Exemplary Name-Value document StartBO:Student @id=studentId1 StartBO:Address houseNumber=17C street=GreenAvenue postalCode=890015 EndBO:Address StartBO:ExamResult courseId=MA0012 marks=75 EndBO:ExamResult EndBO:Student [0060] A Name-Value document may be parsed/tokenized based on newline/whitespace characters.", "A resulting token table listing the token names obtained from parsing the Name-Value document of Table 5 is: [0000] Token Token Names Positions s:Student 1 @id 2 s:Address 3 houseNumber 4 street 5 postalCode 6 e:Address 7 s:ExamResult 8 courseId 9 marks 10 e:ExamResult 11 e:Student 12 [0061] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 Delimited Document Format [0062] Table 6 shows an exemplary delimited document: [0000] TABLE 6 Exemplary Delimited document StartBO:Student~@studentId1~StartBO:Address~17C~Green Avenue~890015~EndBO:Address~ StartBO:ExamResult~MA0012~75~EndBO:ExamResult~EndBO:Student [0063] A delimited document may be parsed/tokenized based on the delimiter, which in the case of the delimited document shown in Table 6, is the tilde ‘˜’.", "A resulting token table listing the token names obtained from parsing the delimited document of Table 6 is: [0000] Token Names Token Positions s:Student 1 @prop1 2 s:Address 3 Prop1 4 Prop2 5 Prop3 6 e:Address 7 s:ExamResult 8 Prop1 9 Prop2 10 e:ExamResult 11 e:Student 12 where prop1, prop2 and prop3 are arbitrarily assigned token names.", "[0064] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 Fixed Width Document Format (20 Characters Fixed Width with ‘#’ as Padding) [0065] Table 7 shows an exemplary delimited document: [0000] TABLE 7 Exemplary Fixed Width document StartBO:Student#####@studentId1#########@studentId1#####StartBO:Address#####17C## ############### Green Avenue########890015##############EndBO:Address#######StartBO:ExamResult##MA 0012############## 75##################EndBO:ExamResult########EndBO:Student####### [0066] A fixed width document may be parsed/tokenized based on the fixed length tokens (in this case 20) and removing the padding characters.", "A resulting token table listing the token names obtained from parsing the fixed width document of Table 7 is: [0000] Token Names Token Positions s:Student 1 @prop1 2 s:Address 3 prop1 4 prop2 5 prop3 6 e:Address 7 s:ExamResult 8 prop1 9 prop2 10 e:ExamResult 11 e:Student 12 where prop1, prop2 and prop3 are arbitrarily assigned token names.", "[0067] The resulting table listing the token values is: [0000] Token Values Token Positions studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 [0068] Once documents are reduced to respective token lists/tables as shown above, the documents become content-type neutral.", "This uniformity enables application of computational techniques in a content-type neutral manner.", "[0069] Returning to FIG. 2 at block B 03 , once a document has been parsed to obtain a token list, the tokens are represented using nested parenthesis notation.", "Representation of the tokens in nested parenthesis notation is described with reference to the exemplary token list/table of Table 8: [0000] TABLE 8 Exemplary token table Token Names s:Student @id s:Address houseNumber street postalCode e:Address s:ExamResult courseId marks e:ExamResult e:Student [0070] The nested parenthesis syntax is arrived at from the tokens such that a start object is assigned a begin parenthesis “(”, an end object is assigned an end parenthesis “)”, and an attribute or value element is assigned a begin parenthesis followed by an end parenthesis “( ).”", "The parenthesis are assigned natural number values sequentially starting from 1 and an end parenthesis is assigned the negative of the begin parenthesis value.", "[0071] Applying the above rules to the exemplary token table of Table 8, obtains a nested notation as follows: [0000] Token Nested Names Parenthesis Values s:Student ( 1 @id ( ) 2 −2 s:Address ( 3 houseNumber ( ) 4 −4 street ( ) 5 −5 postalCode ( ) 6 −6 e:Address ) −3 s:ExamResult ( 7 courseId ( ) 8 −8 marks ( ) 9 −9 e:ExamResult ) −7 e:Student ) −1 [0072] Token labels may be derived from the nested notation.", "Token labels are obtained by removing the end of object tokens, and replacing the start of object indicators “s:”", "with “o:”", "to indicate that these tokens are objects.", "Further, the values in the above nested notation are used as node numbers.", "The token label table obtained in this manner is as follows: [0000] Node Token Labels Numbers s:Student 1 @id 2 o:Address 3 houseNumber 4 street 5 postalCode 6 o:ExamResult 7 courseId 8 marks 9 [0073] The “o:”", "prefix indicates that a token is an object, and the “@”", "prefix indicates that a token is an attribute node.", "[0074] Token values are retained in the same form in which they were initially obtained by the parser, with the exception that the token positions are replaced with node numbers of the same values.", "The token value table is hence defined as follows: [0000] Token Values Node Numbers studentId1 2 17C 4 Green Avenue 5 890015 6 MA0012 9 75 10 [0075] The above node numbers are consecutive in a depth-first order of tree traversal.", "[0076] At block B 04 , a nested parenthesis form of the tree is obtained from the above nested notation.", "The nested parenthesis form is the sequence of values assigned to each parenthesis, namely: 1, 2, −2, 3, 4, −4, 5, −5, 6, −6, −3, 7, 8, −8, 9, −9, −7, −1 [0078] The nested parenthesis form represents the node IDs of the tree of FIG. 1 in depth-first tree traversal order.", "At step B 05 , a Parent-Child Relationship map is obtained from the nested parenthesis form.", "The process of obtaining the Parent-Child Relationship map is described with reference to the flow chart of FIG. 3 .", "[0079] At block H 01 , the sequence of numbers represented by the nested parenthesis form is traversed from left to right until a negative number is encountered.", "The sequence traversed is noted.", "For the above nested parenthesis form, the traversal is: 1, 2 [0081] At block H 02 , when a negative number is encountered (i.e. “−2”), the traversed sequence is copied as a new row of a growing list.", "The rows of the list at this stage are hence: 1, 2 [0083] At blocks H 02 and H 03 , traversal is again performed from left to right but skipping the pair of numbers for which a negative number was encountered in block H 02 .", "That is, the sequence traversed is: 1, 3, 4 [0085] The numbers “2”", "and “−2”", "are skipped, as they are the pair of numbers corresponding to the negative number previously encountered (i.e. “−2). The above traversed sequence is noted, and added as a new row to the growing list: 1, 2 1, 3, 4 [0088] The process at block H 03 is repeated until traversal of the sequence is completed. The resultant list is: [0000] 1, 2 1, 3, 4 1, 3, 5 1, 3, 6 1, 7, 8 1, 7, 9 [0089] At block H 04 , the Parent-Child Relationship map is created from the list. The list is read such that a first number to the left or a second number is a parent node of the second number. Hence, from the first row, node 1 is the parent of node 2 . From the second row, node 1 is the parent of node 3 , and node 3 is the parent of node 4 . In this manner, the Parent-Child Relationship map obtained is: [0000] Parent-Child Relationship map Parent Node Number Child Node Numbers 1 2, 3, 7 3 4, 5, 6 7 8, 9 [0090] At block B 06 , the Parent-Child Relationship map is used to map the depth-first ordered node numbers to breadth-first order. The child node numbers are obtained from the Parent-Child Relationship map: 2, 3, 7, 4, 5, 6, 8, 9 [0092] The first node is prefixed to the sequence of child nodes: 1, 2, 3, 7, 4, 5, 6, 8, 9 [0094] The above sequence represents the breadth-first order of nodes. Adding the above sequence of numbers as a row, adjacent to a row containing the depth-first order of nodes provides the depth-first to breadth-first mapping of nodes: [0000] Depth-first to Breadth-first mapping Depth-First 1 2 3 4 5 6 7 8 9 Breadth-First 1 2 3 5 6 7 4 8 9 [0095] The depth-first to breadth-first mapping and the Parent-Child Relationship map are then used to obtain a Parent-Child ID Map at block B 07 . The process of obtaining the Parent-Child ID map is described with reference to the flow chart of FIG. 4 . [0096] At block I 01 , the depth-first ordered Parent-Child Relationship map is converted to a breadth-first orders using the Depth-first to Breadth-first mapping. The converted Parent-Child Relationship map is: [0000] Parent-Child Relationship Map (Breadth-first) Parent Node Number Child Node Numbers 1 2, 3, 4 3 5, 6, 7 4 8, 9 [0097] At block I 02 , an empty Parent-Child ID Map is then populated by filing in the child row with a sequence of numbers beginning from 2: [0000] Parent-Child ID Map Parent Node ID Child Node ID 2 3 4 5 6 7 8 9 [0098] At block I 03 , the parent row of the Parent-Child ID Map is populated with the node IDs of the corresponding parent node, referring to the breadth-first Parent-Child Relationship map derived at block I 02 . The resultant Parent-Child ID Map is: [0000] Parent-Child ID Map Parent Node ID 1 1 1 3 3 3 4 4 Child Node ID 2 3 4 5 6 7 8 9 [0099] The node numbers of the Parent-Child ID map are hence breadth-first ordered node numbers. [0100] The depth-first to breadth-first mapping is further used to arrange the Token Labels table and the Token Values table from a depth-first ordered sequence to a breadth-first ordered sequence (block B 08 ). The resultant rearranged tables are: [0000] Token Labels Node Token Labels Numbers o:Student 1 @id 2 o:Address 3 oExamResult 4 houseNumber 5 Street 6 postalCode 7 courseId 8 marks 9 [0101] The o: prefix indicates that the token is an object, and the @ prefix indicates that the token is an attribute node [0000] Token Values Token Values Node Numbers studentId1 2 17C 5 Green Avenue 6 890015 7 MA0012 8 75 9 [0102] From the rearranged Token Labels table and Token Values table, a token can be differentiated as being an object, value element, or attribute. The tokens in the Token Values table which are not attributes are value elements. Node 2 is an attribute token. The remaining nodes, nodes 5 , 6 , 7 , 8 , and 9 , are value element nodes. The tree represented by the above tables is converted to its second form by adding #text nodes to the value element nodes (block B 09 ). [0103] Conversion of the tree to its second form involves determining the number of value element nodes from the token value list and the last node ID of the tree in first form. The number of value elements for the above tree is 5, and the last node ID is 9. A sequence of numbers equal to the number of value elements starting from the next number after the last node ID is then generated. A sequence of 5 numbers beginning from 10 is hence generated, namely 10, 11, 12, 13, and 14. [0104] The Parent-Child ID Map is then modified by extending the number of columns by the number of numbers in the sequence: [0000] Parent-Child Id Map (modified) Parent 1 1 1 3 3 3 4 4 — — — — — Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0105] The incomplete parent row of the modified Parent-Child ID Map is then filled in consecutively with the node numbers of the nodes which are value elements. Namely, 5, 6, 7, 8, and 9: [0000] Parent-Child ID Map (modified) Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0106] #text nodes are added to the Token Labels table corresponding to the newly added node numbers: [0000] Node Token Labels Numbers o:Student 1 @id 2 o:Address 3 o:ExamResult 4 houseNumber 5 Street 6 postalCode 7 courseId 8 marks 9 #text 10 #text 11 #text 12 #text 13 #text 14 [0107] Then, referring to the Parent-Child ID Map, the Token Values table is modified such that the node numbers in the Token Values table are replaced with the newly generated node numbers of the #text node: [0000] Token Values Node Numbers (old) Node Numbers (new) studentId1 2 2 17C 5 10 Green Avenue 6 11 890015 7 12 MA0012 8 13 75 9 14 [0108] In this manner, the tree is converted to its second form, with #text nodes. The tree is shown in FIG. 5 . [0109] At block B 10 , the structure code is obtained from the Parent-Child ID Map according to the computation disclosed in U.S. application Ser. No. ______ [IBM Docket No. IN920060037US1], incorporated herein by reference. The structure code is 52055003000. [0110] The structure code obtained from the above computation represents the tree structure uniquely. However to overcome certain special cases where two semantically different documents have the same tree structure, node Ids of special nodes (if any) need to be appended to the structure code obtained in the previous step. This will give the final structure code. These special cases are disclosed in U.S. application Ser. No. ______[IBM Docket No. IN920060037US1], with reference to XML documents, which are equally applicable for other tree based documents. [0111] From the above, the structure code, labels, and values of the tree are obtained. Namely: S=52055003000 L={Student, id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks, #text, #text, #text, #text, #text} V={studentId1, 17C, Green Avenue, 890015, MA0012, 75}. C=The content is as specified by the user, and is text/xml for example. [0116] At block B 11 , the above SLVC elements are compiled and the document is hence represented in SLVC representation. Object Tree to SLVC [0117] Construction of a CTDT from an object tree takes as input the object, the object-type of the object, and configuration data for data transformation. [0118] FIG. 6 shows an exemplary object tree. The object tree is in first form, meaning that no #text nodes are present. Attribute nodes in the object tree are identified with a “@”", "prefix before the attribute name.", "Conversion of the object tree to SLVC representation is described with reference to the flow chart of FIG. 7 .", "[0119] At block E 01 , the object tree is traversed in breadth-first order, and node IDs assigned to each node in this order.", "In FIG. 6 , node IDs are shown inside each node.", "At block E 02 , a Parent-Child ID Map of the object tree is created.", "The Parent-Child ID Map can be created directly from the object tree as parent-child relationships between nodes are explicitly apparent from the object tree.", "The Parent-Child ID Map for the object tree of FIG. 6 is: [0000] Parent-Child ID Map Parent Node Id 1 1 1 3 3 3 4 4 Child Node Id 2 3 4 5 6 7 8 9 [0120] At block E 03 , a label list in which the position of the nodes in the list correspond to the node ID of the object tree in breadth-first order is created.", "The label list is: Labels={Student, #id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks} [0122] At block E 04 , the leaf nodes of the object tree are determined from the Parent-Child ID Map generated at block E 02 .", "The leaf nodes are obtained from the Parent-Child ID Map as follows.", "The leaf nodes are those nodes which are present in the child row of the Parent-Child Id Map and not present in the parent row of the Parent-Child Id Map.", "Leaf nodes={2, 5, 6, 7, 8, 9} [0124] At block E 05 , the values of the leaf nodes are obtained from the tree: Values={studentId1, 17C, Green Avenue, 890015, MA0012, 75} [0126] At block E 06 , the attribute nodes of the tree are determined from the label list obtained at block E 03 .", "As previously described, the attribute nodes are the nodes whose labels bear a predetermined label.", "In the present example, nodes prefixed with “@”", "are attribute nodes.", "A list of attribute nodes is: Attribute Nodes={2} [0128] At block E 07 , the value element nodes of the tree are determined from the leaf node list.", "The value element nodes are the nodes of the leaf node list which are not attribute nodes.", "The list of value element nodes is hence: Value Element Nodes={5, 6, 7, 8, 9} [0130] It should be noted that for a tree in second form, the value element nodes are the parent nodes of #text nodes.", "[0131] The tree is converted to second from at block E 08 by adding #text nodes, in the manner as described previously with reference to conversion of a document to SLVC representation.", "The Parent-Child ID Map of the object tree after conversion to second form is: [0000] Parent-Child ID Map (second form) Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0132] And the labels list is: Labels (second form)={Student, #id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks, #text, #text, #text, #text, #text} [0134] It should be understood that if the input tree was already in second form, the conversion performed at block E 08 may be skipped.", "[0135] At block E 09 , the structure code is determined from the Parent-Child ID Map according to the computation as described previously with reference to conversion of a document to SLVC representation.", "The structure code is: 52055003000.", "[0136] In the above manner, all SLVC elements are determined.", "Specifically: S=52055003000 L={Student, #id, Address, ExamResult, houseNumber, street, postalCode, courseId, marks, #text, #text, #text, #text} V={studentId1, 17C, Green Avenue, 890015, MA0012, 75} C=commonj.", "sdo.", "DataObject (specified by the user) [0141] At block E 10 , the SLVC elements are compiled and the object tree is hence represented in SLVC representation.", "[0000] Conversion from CTDT SLVC to Document Conversion [0142] Conversion of a CTDT from an SLVC representation to a tree-structure based document takes as input the SLVC representation, and any configuration data that may be required for data transformation.", "Conversion of a CTDT from an SLVC representation to a tree-structure based document is described with reference to the exemplary SLVC representation of table 7 and the flow chart of FIG. 8 .", "[0000] TABLE 7 Exemplary SLVC data S = 52055003000 L = {Student, id, Address, ExamResult, houseNumber, street, PostalCode, courseID, marks, #text, #text, #text, #text, #text,} V = {studentID1, 17C, Green Avenue, 890015, MA0012, 75} C = text/xml (specified by user) [0143] At block F 01 , a Parent-Child ID Map is obtained from the structure code of the SLVC representation.", "The Parent-Child ID Map is obtained from the structure code using the technique described in co-pending U.S. application Ser.", "No. ______[IBM Docket No. IN920060037US1].", "[0144] The Parent-Child ID Map is: [0000] Parent-Child ID Map Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id where the node IDs are breadth-first ordered.", "[0145] In cases where the structure code has special nodes appended, as described in co-pending U.S. application Ser.", "No. ______ [IBM Docket No. IN920060038US1], the above computation applies to the first part of the structure code which is obtained by separating it from the appended special nodes.", "[0146] At block F 02 , from the label list L, the node IDs of the #text nodes are identified.", "The node IDs are: #text node IDs={10, 11, 12, 13, 14} [0148] At block F 03 , the Parent-Child ID Map, which is in the second form, is converted to the first form by removing the #text nodes from the map and transforming the Parent-Child ID Map.", "The columns of the Parent-Child ID Map containing the #text node IDs are removed.", "The Parent-Child ID Map in first form is: [0000] Parent-Child ID Map (first form) Parent Node Id 1 1 1 3 3 3 4 4 Child Node Id 2 3 4 5 6 7 8 9 [0149] At block F 04 , a Parent-Child Relationship Map is derived from the Parent-Child ID Map (first form).", "The Parent-Child ID Map gives the mapping between parent nodes and child nodes.", "When a parent node has multiple child nodes, the relationships are repeated.", "If the Parent-Child mapping are not repeated, and each parent node is associated with all its children, the Parent-Child Relationship Map is obtained.", "The Parent-Child Relationship Map derived in this manner is in breath-first order and is: [0000] Parent-Child Relationship Map (breadth-first) Parent Node Id Child Node Ids 1 2, 3, 4 3 5, 6, 7 4 8, 9 [0150] At block F 05 , a breadth-first to depth-first node mapping is obtained from the Parent-Child ID Map (first form).", "[0151] The process of obtaining the breadth-first to depth-first node mapping is described with reference to the flow chart of FIG. 9 , and the Parent-Child Relationship map (breadth-first).", "[0000] Parent-Child Relationship Map (breadth-first) Parent Node Number Child Node Numbers 1 2, 3, 4 3 5, 6, 7 4 8, 9 [0152] At block K 01 , the key and value of the lower most row of the Parent-Child Relationship map (breadth-first) is obtained: 4: 8, 9 [0154] At block K 02 , the key obtained at block K 01 is searched for in the value column of the Parent-Child Relationship map (breadth-first).", "The values obtained at block K 01 are appended to the values of the row containing the key in its value column, and the lower most row is deleted.", "[0000] Parent-Child Relationship map (modified) Parent Node Number Child Node Numbers 1 2, 3, 4, 8, 9 3 5, 6, 7 [0155] Block K 02 is repeated until the table has only one row: [0000] Parent-Child Relationship map (modified) Parent Node Number Child Node Numbers 1 2, 3, 5, 6, 7, 4, 8, 9 [0156] At block K 03 , the key and values of the modified Parent-Child Relationship map are concatenated to form a row: [0000] 1, 2, 3, 5, 6, 7, 4, 8, 9 [0157] The breadth-first to depth-first map is created from the above row, and a new row containing a sequence of numbers representing the depth-first order of nodes: [0000] Breadth-First to Depth-First node mapping Breadth-First 1, 2, 3, 5, 6, 7, 4, 8, 9 Depth-First 1, 2, 3, 4, 5, 6, 7, 8, 9 [0158] The above map may be sorted by Breadth-first order to facilitate easier reference: [0000] Breadth-first to Depth-first node mapping Breadth-First 1 2 3 4 5 6 7 8 9 Depth-First 1 2 3 7 4 5 6 8 9 [0159] At block F 06 , the Parent-Child Relationship Map in breadth-first order is transformed to depth-first order using the breadth-first to depth-first node mapping.", "The transformed Parent-Child Relationship Map in depth-first order is: [0000] Parent-Child Relationship Map (depth-first) Parent Node Id Child Node Ids 1 2, 3, 7 3 4, 5, 6 7 8, 9 [0160] At block F 07 , the labels from the SLVC representation are separated into a Token Name list without the #text nodes.", "The Token Name list is: Token Name list (breadth-first)={Student, ID, Address, ExamResult, houseNumber, street, postalCode, courseID, marks} [0162] The position of the nodes corresponds to the node IDs of the tree.", "[0163] At block F 08 , the token name list is modified to mark the attribute nodes with a predetermined identifier.", "The attribute nodes can be identified by identifying all leaf nodes which are not #text nodes.", "From the Parent-Child Id Map (second form) the leaf nodes are those nodes which are present in the child row but not in the parent row of the Parent-Child ID map.", "Therefore the leaf nodes are: Leaf nodes={2, 10, 11, 12, 13, 14} [0165] Any leaf node whose parent has a grandchild is an attribute node if it is not a special node.", "Since node Ids of special nodes are appended with the structure code, it is known which nodes are special nodes.", "Any leaf node which is not an attribute node is a #text node.", "[0166] Special nodes are described in further detail in co-pending U.S. application Ser.", "No. ______ [IBM Docket No. IN920060038US1] with reference to XML data, but is equally applicable to other tree-based data.", "Knowing the parent-child hierarchy of node Ids from the Parent-Child ID map (second form), the #text nodes are determined as described above.", "The #text nodes are hence: #text nodes={10, 11, 12,13, 14} [0168] The attribute node is hence: Attribute nodes={2} [0170] In the present example, the attribute nodes in the Token Name list are marked with an ‘@’ prefix.", "The Token list is hence: Token Name list (breadth-first)={Student, @id, Address, ExamResult, houseNumber, street, postalCode, courseID, marks} [0172] At block F 09 , the object nodes are identified from the structure code, and identified in the Token Name list.", "The object nodes are identified as nodes which are neither attribute nodes, value element nodes, nor #text nodes.", "The #text nodes are already known.", "The value element nodes are the parent nodes of the #text nodes and are hence: Value Element nodes={5, 6, 7, 8, 9} [0174] The object nodes are hence: Object nodes={1, 3, 4} [0176] In the present example, the object nodes are marked with an “o:”", "prefix in the Token Names list.", "The Token list is hence: [0177] Token Name list (breadth-first)={o:Student, @id, o:Address, o:ExamResult, houseNumber, street, postalCode, courseID, marks} [0178] At block, F 10 the node IDs of the nodes containing values (breadth-first order) are obtained.", "This is a combination of attribute nodes and value element nodes.", "The node IDs sorted in ascending order are: Nodes containing values (breadth-first)={2, 5, 6, 7, 8, 9} [0180] At block F 11 , the Token Name list is arranged in depth-first order using the Breadth-first to Depth-first mapping previously determined.", "Token Name list (depth-first)={o:Student, @id, o:Address, houseNumber, street, postalCode, o:ExamResult, courseID, marks} [0182] At block F 12 , the list of nodes containing values obtained at block F 10 is transformed from a listing of breadth-first IDs to a listing of depth-first IDs using the breadth-first to depth-first mapping: Nodes containing values (depth-first)={2, 4, 5, 6, 8, 9} [0184] At block F 13 , the child nodes for each object node in the Token Name list (depth-first) are identified using the depth-first Parent-Child Relationship map obtained at block F 06 .", "An end object indicator is added to the Token Name list after the last child node of each object node.", "Object prefixes “o:”", "are replaced with an object start prefix “s:.”", "For example, from the Parent-Child Relationship map (depth-first), it is determined that the child nodes of the “Address”", "node (having node ID 3 ), are nodes 4 , 5 and 6 .", "The last child node of the object node “Address”", "is therefore node 6 , which is 3 nodes away from the object node “o:Address.”", "A new entry “e:Address”", "is therefore added to the Token Name list 3 entries from “o:Address”, and “o:Address”", "is renamed “s:Address.”", "This modification is performed for each object name in the Token Name list.", "[0185] The Token Name list after this process is: Token Name list (depth-first)={s:Student, #id, s:Address, houseNumber, street, postaIC ode, e:Address, s:ExamResult, courseID, marks, e:ExamResult, e:Student} [0187] At block F 14 , the node IDs in the list of nodes containing values (depth-first) is adjusted by adding to each node ID in the list, the number of end object nodes between the first node and each node, respectively.", "Referring, for example, to the node having node ID 8 in the list of nodes containing values (depth-first), the number of end object nodes between this node and the first node of the Token Name list is determined: [0188] The node having node ID 8 in the list of nodes containing values (depth-first) is “courseID.”", "[0189] The nodes between first node and the “courseID”", "node are: s:Student @id s:Address houseNumber street postalCode e:Address (*) s:ExamResult [0198] The number of end object nodes is 1, being the “e:Address”", "node.", "Node ID 8 in the list of nodes containing values (depth-first) is hence adjusted by adding 1, giving it an adjusted Node ID of 9.", "Performing this adjustment to each node in the list of node containing values (depth-first) yields an adjusted list of nodes: Nodes containing values (depth-first, adjusted)={2, 4, 5, 6, 9, 10} [0200] At block F 15 , the Token Name list, Token Value list, and list of nodes containing values is submitted to a data transformer corresponding to a data transformer appropriate for the content type specified by the SLVC representation.", "The data transformer hence receives as input: Token Name list (depth-first)={s:Student, @id, s:Address, houseNumber, street, postalCode, e:Address, s:ExamResult, courseId, marks, e:ExamResult, e:Student} Token Value list={studentId1, 17C, Green Avenue, 890015, MA0012, 75} Nodes containing values (depth-first, adjusted)={2, 4, 5, 6, 9, 10} [0204] From the above information, the data transformer reproduces a document (for example, an XML document).", "SLVC to Object Conversion [0205] Conversion of a CTDT from an SLVC representation to an object tree takes as input the SLVC representation, and any configuration data that may be required for data transformation.", "Conversion of a CTDT from an SLVC representation to an object tree is described with reference to the exemplary SLVC representation of table 9.", "and the flow chart of FIG. 10 .", "[0000] TABLE 7 Exemplary SLVC data S = 52055003000 L = {Student, id, Address, ExamResult, houseNumber, street, PostalCode, courseID, marks, #text, #text, #text, #text, #text,} V = {studentID1, 17C, Green Avenue, 890015, MA0012, 75} C = commonj.", "sdo.", "DataObject (specified by user) [0206] At block G 01 , a Parent-Child ID map is created from the structure code of the SLVC representation, as described in the above co-pending U.S. application Ser.", "No. ______ [IBM Docket No. IN920060037US1].", "The Parent-Child ID map is in second form, including #text nodes: [0000] Parent-Child ID Map (breadth-first, second form) Parent 1 1 1 3 3 3 4 4 5 6 7 8 9 Node Id Child 2 3 4 5 6 7 8 9 10 11 12 13 14 Node Id [0207] At block G 02 , the node IDs of the #text nodes are determined from the labels list of the SLVC representation.", "The Node IDs are obtained from the position of the #text nodes in the labels list: The Node IDs correspond to the position indices of the #text nodes in the labels list if the position index of the first element is taken as 1.", "#text nodes={10, 11 12, 13, 14} [0209] At block G 03 , the #text nodes are removed from the Parent-Child ID map if the object tree to be output does not require #text nodes to be retained.", "Otherwise, the conversion skips to block G 04 : [0000] Parent-Child ID Map (#text nodes removed) Parent Node Id 1 1 1 3 3 3 4 4 Child Node Id 2 3 4 5 6 7 8 9 [0210] At block G 04 , the leaf nodes are determined from the Parent-Child ID map: Leaf nodes={2, 5, 6, 7, 8, 9} [0212] At block G 05 , the object nodes are determined from the Parent-Child ID map.", "The object nodes here are the non-leaf nodes since the tree is in first-form: Object nodes={1, 3, 4} [0214] At block G 06 , an object tree of a type specified by the object type in the SLVC representation is created.", "The object tree has node names as obtained from the labels list, value nodes having values corresponding to the leaf nodes, and parent-child relationship between nodes as given by the Parent-Child ID Map.", "[0215] The above method of converting tree-structure based documents and object trees to/from SLVC representation, may be implemented using a computer system 1200 , such as that shown in FIG. 11 wherein the processes of FIGS. 3 to 5 and 8 to 10 may be implemented as software, such as one or more application programs executable within the computer system 1200 .", "In particular, the steps of the described methods/processes are effected by instructions in the software that are carried out within the computer system 1200 .", "The instructions may be formed as one or more code modules, each for performing one or more particular tasks.", "The software may also be divided into two separate parts, in which a first part and the corresponding code modules performs the conversion methods and a second part and the corresponding code modules manage a user interface between the first part and the user.", "[0216] The software may be stored in a computer readable medium, including the storage devices described below, for example.", "The software is loaded into the computer system 1200 from the computer readable medium, and then executed by the computer system 1200 .", "A computer readable medium having such software or computer program recorded on it is a computer program product.", "The use of the computer program product in the computer system 1200 preferably effects an advantageous apparatus for converting tree-structure based documents and object trees to an SLVC representation, and vice versa.", "[0217] As seen in FIG. 11 , the computer system 1200 is formed by a computer module 1201 , input devices such as a keyboard 1202 and a mouse pointer device 1203 , and output devices including a printer 1215 , a display device 1214 and loudspeakers 1217 .", "An external Modulator-Demodulator (Modem) transceiver device 1216 may be used by the computer module 1201 for communicating to and from a communications network 1220 via a connection 1221 .", "The network 1220 may be a wide-area network (WAN), such as the Internet or a private WAN.", "Where the connection 1221 is a telephone line, the modem 1216 may be a traditional dial-up modem.", "Alternatively, where the connection 1221 is a high capacity (eg: cable) connection, the modem 1216 may be a broadband modem.", "A wireless modem may also be used for wireless connection to the network 1220 .", "[0218] The computer module 1201 typically includes at least one processor unit 1205 , and a memory unit 1206 for example formed from semiconductor random access memory (RAM) and read only memory (ROM).", "The module 1201 also includes an number of input/output (I/O) interfaces including an audio-video interface 1207 that couples to the video display 1214 and loudspeakers 1217 , an I/O interface 1213 for the keyboard 1202 and mouse 1203 and optionally a joystick (not illustrated), and an interface 1208 for the external modem 1216 and printer 1215 .", "In some implementations, the modem 1216 may be incorporated within the computer module 1201 , for example within the interface 1208 .", "The computer module 1201 also has a local network interface 1211 which, via a connection 1223 , permits coupling of the computer system 1200 to a local computer network 1222 , known as a Local Area Network (LAN).", "As also illustrated, the local network 1222 may also couple to the wide network 1220 via a connection 1224 , which would typically include a so-called firewall device or similar functionality.", "The interface 1211 may be formed by an Ethernet™ circuit card, a wireless Bluetooth™ or an IEEE 802.11 wireless arrangement.", "[0219] The interfaces 1208 and 1213 may afford both serial and parallel connectivity, the former typically being implemented according to the Universal Serial Bus (USB) standards and having corresponding USB connectors (not illustrated).", "Storage devices 1209 are provided and typically include a hard disk drive (HDD) 1210 .", "Other devices such as a floppy disk drive and a magnetic tape drive (not illustrated) may also be used.", "An optical disk drive 1212 is typically provided to act as a non-volatile source of data.", "Portable memory devices, such optical disks (eg: CD-ROM, DVD), USB-RAM, and floppy disks for example may then be used as appropriate sources of data to the system 1200 .", "[0220] The components 1205 , to 1213 of the computer module 1201 typically communicate via an interconnected bus 1204 and in a manner which results in a conventional mode of operation of the computer system 1200 known to those in the relevant art.", "Examples of computers on which the described arrangements can be practised include IBM-PC and compatibles, Sun Sparcstations, Apple Mac™ or alike computer systems evolved therefrom.", "[0221] Typically, the application programs discussed above are resident on the hard disk drive 1210 and read and controlled in execution by the processor 1205 .", "Intermediate storage of such programs and any data fetched from the networks 1220 and 1222 may be accomplished using the semiconductor memory 1206 , possibly in concert with the hard disk drive 1210 .", "In some instances, the application programs may be supplied to the user encoded on one or more CD-ROM and read via the corresponding drive 1212 , or alternatively may be read by the user from the networks 1220 or 1222 .", "Still further, the software can also be loaded into the computer system 1200 from other computer readable media.", "Computer readable media refers to any storage medium that participates in providing instructions and/or data to the computer system 1200 for execution and/or processing.", "Examples of such media include floppy disks, magnetic tape, CD-ROM, a hard disk drive, a ROM or integrated circuit, a magneto-optical disk, or a computer readable card such as a PCMCIA card and the like, whether or not such devices are internal or external of the computer module 1201 .", "Examples of computer readable transmission media that may also participate in the provision of instructions and/or data include radio or infra-red transmission channels as well as a network connection to another computer or networked device, and the Internet or Intranets including e-mail transmissions and information recorded on Websites and the like.", "[0222] The second part of the application programs and the corresponding code modules mentioned above may be executed to implement one or more graphical user interfaces (GUIs) to be rendered or otherwise represented upon the display 1214 .", "Through manipulation of the keyboard 1202 and the mouse 1203 , a user of the computer system 1200 and the application may manipulate the interface to provide controlling commands and/or input to the applications associated with the GUI(s).", "[0223] The method of converting tree-structure based documents and object trees to/from SLVC representation may alternatively be implemented in dedicated hardware such as one or more integrated circuits.", "Such dedicated hardware may include graphic processors, digital signal processors, or one or more microprocessors and associated memories.", "[0224] The foregoing describes only some embodiments of the present invention, and modifications and/or changes can be made thereto without departing from the scope and spirit of the invention, the embodiments being illustrative and not restrictive." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention teaches use of an adaptive deconvolution method for enhancing the vertical resolution of an MWD (measurement while drilling) electromagnetic logging tool. 2. Discussion of Related Art Wireline induction logging tools are well known in the art of studying the formation characteristics of the earth through which a borehole has been drilled. Typically, a sonde, carrying one or more transmitting coils and one or more receiving coils, is lowered into the borehole on the end of a multi-conductor cable. An AC signal, at a frequency on the order of 20 kHz excites the transmitter coil. Radiation from the transmitter generates an electromagnetic field in the formation which, in turn, induces a flow of eddy currents therein. Variations in the magnitude of the eddy currents due to variations in the formation conductivity (or its inverse, resistivity) are detected by the receivers. The magnitude of formation conductivity is diagnostic of certain parameters of the earth layers that were penetrated by the borehole. Although other types of tools are known for measuring resistivity, induction tools are preferred in many cases for operational reasons. A quantitative measure of the conductivity is determined by measuring the value of the voltage induced in the receiver coil that is in-phase with the transmitter current (the real or R component). The real signal is a nonlinear function of conductivity. A quadrature component (X-component) signal can also be measured and be combined with the real component such that the resulting value is a linear function of conductivity. The term "vertical geometric factor" (VGF), or the impulse response is used by those skilled in the art to describe the response of an induction tool to a thin conductive layer. The impulse response of a typical induction tool in a homogeneous formation is a curve that has a main lobe of finite width that spans a length of the borehole and an amplitude that is an inverse non-linear function of the formation conductivity (N.B. the unit of measurement for conductivity is mho and for borehole applications, 0.001 mho or mmho. Some authors use units of resistivity which are measured in ohm-meters. The terms are often used interchangeably). Although most of the signal originates from the main lobe, unwanted side lobes of non-zero amplitudes extend vertically above and beneath the main lobe. In thin beds of low conductivity, the unwanted contribution of the side lobes from adjacent beds that have higher conductivity, will cause the thin-bed measurements to be too high. That error is called the "shoulder effect". As before stated, the magnitude of impulse response of the induction logging tool is an inverse function of formation conductivity but that function is non-linear. The non-linearity is referred to as the "skin effect". The magnitude of the skin effect is also a complex function of the system operating frequency and coil separation. Various methods have been used in the prior-art borehole logging sondes to counteract the problems cited. For example, see U.S. Pat. No. 4,471,436, issued Sep. 11, 1984 to R. T. Schaefer et al. for PHASOR PROCESSING OF INDUCTION LOGS INCLUDING SHOULDER AND SKIN EFFECTS. Shoulder effect is reduced by generating a spatial deconvolution filter which sharpens the main lobe and reduces the side lobes when the filter is convolved with the VGF. The skin effect is reduced by filtering the quadrature phase component measurements according to a non-linear spatial filtering function to obtain a correction representative of the change in sonde response function as a function of the formation conductivity. The correction component measurements are then summed with the processed in-phase component measurement to produce a processed log measurement sans the unwanted side-lobe contributions. There are certain technical differences between wireline logging tools as described above and tools used in measurement-while-drilling (MWD). In the latter case, the transmitter and receiving coils of the tool are mounted on a highly-conductive metal mandrel to withstand the drilling stresses during operation. The physical configuration of the conductive mandrel and the transmitter/receiver coils requires that the coils be excited at a frequency on the order of MHz. This tool is thus also named as a propagated wave resistivity tool. Whereas the prior-art wireline tools depended upon a combination of the real and quadrature components to derive apparent conductivity, the propagated wave resistivity tool of this invention relies on the phase difference between the measured signals in the two receiver coils. Therefore, the way of evaluating the VGF impulse response function for MWD is different from that for wireline induction application. See for example MWD Resistivity Tool Response In A Layered Medium, by Q. Zhou et al., Geophysics, November 1991, pp. 1738-1748. Also Geometric Factor and Adaptive Deconvolution of MWD-PWR Tools, by Q. Zhou et al., The Log Analyst, July-August, 1992 pp. 390-398. SUMMARY OF THE INVENTION In accordance with this invention, a propagated wave resistivity tool measures the phase differences between the voltages induced in two receiver coils as the electromagnetic wave propagates through the formation volume to which the tool is responsive. The measured phase differences are averaged to determine a background phase. A deconvolution filter appropriate to the current position of the tool in the formation volume of interest is derived based upon the averaged value of the phase differences which may be a weighted average. The measured phase differences are spatially deconvolved thereby to enhance the vertical resolution of the measurements by reducing the shoulder effects. BRIEF DESCRIPTION OF THE DRAWINGS The novel features which are believed to be characteristic of the invention, both as to organization and methods of operation, together with the objects and advantages thereof, will be better understood from the following detailed description and the drawings wherein the invention is illustrated by way of example for the purpose of illustration and description only and are not intended as a definition of the limits of the invention: FIG. 1a illustrates an MWD logging tool; FIG. 1b is an electrical equivalent of two transmitter coils and two receiver coils; FIG. 2 shows the VGF impulse response for phase for the array of FIG. 1b, for four constant background formation conductivity values; FIG. 3 is a graph of phase difference as a function of resistivity (conductivity -1 ) in a homogeneous formation; FIG. 4 shows the vertical resolution enhancement for a sequence of formation beds. DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1a, there is shown the lower end 10 of an MWD tool as employed in drilling a borehole. The tool consists of a mandrel 10 about 6.75" in diameter and which is usually made of non-magnetic alloy. A drill bit 12 is screwed to the bottom of the mandrel in a manner well known in the art. Transmitter coils or antennas T 1 and T 2 are wound in suitable grooves that are 1.7 meters apart. Receiver coils or antennas R 1 and R 2 that are themselves spaced apart by 0.3 meter are mounted 0.7 meter from the respective transmitter antennas. For an MWD tool, the transmitter antennas are alternately excited at an excitation frequency of 1 MHz. The electromagnetic equivalent of the tool approximates a vertical magnetic dipole (VMD) as shown in FIG. 1b. The formation volume to which the tool is primarily responsive is the spatial interval encompassed by the receiving antennas or coils. The point of measurement is usually taken as the midpoint between the receiver coils or antennas. The propagated wave resistivity tool of this invention measures the change in phase between the voltages induced in two spaced-apart receiver antennas as an electromagnetic field, launched from a transmitter antenna, propagates through the surrounding formation between the antennas, the electromagnetic field being guided by the conductive mandrel. For simplicity of the mathematic expressions, one transmitter and one receiver will be assumed. In an azimuthally symmetric formation, it can be shown that the geometric factor for phase and amplitude is given by: ##EQU1## where: E P (r,r T )=the electric field in the azimuthal direction for a source at r T and observation point at r, E P (r R ,r T )=the electric field in the azimuthal direction for a source at r T and receiver point at r R , G(r R ,r)=Green's function relating the eddy current at r to the field at r R , and C=a normalizing constant that depends upon the tool geometry and is given by C=(ωμL.sup.2)/2. (2) Under the dipole approximation of the coils, ##EQU2## In the above formulations, L=coil separation, k O 2 =iωμσ O , μ=magnetic permeability of formation in air, σ O =formation background conductivity, ω=angular frequency. The vertical geometric factor g v for phase can be derived by integrating the imaginary part of g(r; r R , r T ) from equation (1) over the radius from zero to infinity: ##EQU3## FIG. 2 is the phase impulse response for a two transmitter, two receiver system for four different formation conductivities, σ O =0.01, 0.10, 0.32 and 3.16, represented by curves 14, 16, 18 and 20 respectively. From the response curves, one can appreciate that the response is broader at low conductivities than at high conductivity. Decreased vertical spatial resolution results for a resistive formation because the electromagnetic field penetrates further into more resistive formations than in a conductive formation. With the VGF known from the impulse response curves of FIG. 2, it becomes possible to enhance and to reshape the tool responses to provide better vertical resolution and symmetric response characteristics. However, because the VGFs are dependent upon the background conductivity and the phase measurement is non-linear with respect to the formation conductivity, an adaptive deconvolution method is required. Equation (4) provides the VGF impulse response function necessary for deconvolution. In conventional induction logging, the apparent conductivity is derived by dividing the measured voltage by a normalizing constant. The nonlinear nature of the problem at high conductivity is corrected by application of a skin effect correction. In the propagated wave resistivity tool of this invention, the conversion from measured phase difference to apparent conductivity is made with the aid of the computed homogeneous formation phase response curve shown in FIG. 3. The nonlinear response in a homogeneous formation is inherently reflected in the conversion. The phase difference will be deconvolved to provide the argument entry for determining apparent conductivity according to the curve in FIG. 3. It will be assumed that conductivity is a function of z (depth) only and the tool will be assumed to be perpendicular to the layer surfaces. The perturbation of the phase difference θ S from θ O which would exist in a particular background conductivity σ O can be shown to be ##EQU4## In the Fourier domain, (5) becomes Θ=CΣG.sub.V (6) where Θ, Σ and G v are the Fourier transforms of 8 s , θ S ,[σ(z)-σ O ] and g v respectively. Ideally, the conductivity can be derived from Σ=Θ/(CG.sub.v). (7) Formulation (7) turns out to be unstable due to physical tool-measurement limitations. Preferably, a suitable low-pass filter such as Gaussian filter function, T, but not limited thereto, is introduced to band-limit the deconvolution as follows: ##EQU5## The half-width of the filter function is adjusted based upon prior experience in the region under study, to control the vertical resolution enhancement. In (8) the adaptive deconvolution filter function in the Fourier domain is T/G v . Its inverse transform is the space domain deconvolution filter. In operation, as the tool is drawn through a borehole drilled into a formation of interest, the transmitters are alternately excited to transmit an electromagnetic wave past the receiver coils. The phase difference between the voltages induced in the receiver antennas are measured at a plurality of different levels and recorded by a suitable recording means of any well known type (not shown). A plurality of phase VGF's or impulse response curves are precalculated for a range of conductivities that are expected to be encountered in earth formations. Typical curves such as shown in FIG. 2 may be generated for a plurality of different estimated conductivities. A corresponding plurality of exemplary deconvolution filters are created from the precalculated phase impulse response functions. Next, the measured phase differences are averaged over a spatial interval corresponding to the formation volume in which the tool is currently located and to which the tool is responsive to provide an average background phase value within the formation volume of interest. Preferably the measurements are weighted prior to averaging by application of weighting coefficients derived from some desired function that may be Gaussian but is not limited thereto. A new deconvolution filter that is appropriate to the current formation volume is computed by interpolating between the plurality of exemplary deconvolution filters. The current phase measurements are deconvolved with the aid of the new deconvolution filter. Shaping operators such as a Hamming or a Blackman window may be applied to the data set to minimize side lobes. The process is repeated for other levels in the borehole. The deconvolution process is adapted to the changing parameters along the borehole by choosing an appropriate deconvolution filter that depends upon the weighted conductivity around each depth level of interest. FIG. 4 is a showing of the vertical resolution enhancement for a model of a sequence of formation beds. The coordinates are a linear vertical depth scale vs. apparent resistivity in ohm-meters on a logarithmic scale. The solid lines 22 represent the model (true) formation layers; the short dashed lines 26 depict the raw data; the broken lines 24 are the results of applying the teachings of this invention. This invention has been described with a certain specificity by way of example but not by way of limitation. Those skilled in the art will consider other techniques for performing the disclosed process which will fall within the scope and spirit of this invention which is limited only by the appended claims.
This invention discloses an adaptive deconvolution method for enhancing the vertical resolution of an MWD (measurement-while-drilling) electromagnetic resistivity logging tool. The tool measures the total differences between the voltages induced in a pair of spaced-apart receiver coils. A deconvolution filter, appropriate to the current position of the logging tool in the borehole, is derived according to the weighted average of the measured phase differences. Using the so-derived deconvolution filter, the measured phase differences are spatially deconvolved thereby to enhance the vertical resolution of the measurements by reducing the shoulder-bed effects.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This invention teaches use of an adaptive deconvolution method for enhancing the vertical resolution of an MWD (measurement while drilling) electromagnetic logging tool.", "Discussion of Related Art Wireline induction logging tools are well known in the art of studying the formation characteristics of the earth through which a borehole has been drilled.", "Typically, a sonde, carrying one or more transmitting coils and one or more receiving coils, is lowered into the borehole on the end of a multi-conductor cable.", "An AC signal, at a frequency on the order of 20 kHz excites the transmitter coil.", "Radiation from the transmitter generates an electromagnetic field in the formation which, in turn, induces a flow of eddy currents therein.", "Variations in the magnitude of the eddy currents due to variations in the formation conductivity (or its inverse, resistivity) are detected by the receivers.", "The magnitude of formation conductivity is diagnostic of certain parameters of the earth layers that were penetrated by the borehole.", "Although other types of tools are known for measuring resistivity, induction tools are preferred in many cases for operational reasons.", "A quantitative measure of the conductivity is determined by measuring the value of the voltage induced in the receiver coil that is in-phase with the transmitter current (the real or R component).", "The real signal is a nonlinear function of conductivity.", "A quadrature component (X-component) signal can also be measured and be combined with the real component such that the resulting value is a linear function of conductivity.", "The term "vertical geometric factor"", "(VGF), or the impulse response is used by those skilled in the art to describe the response of an induction tool to a thin conductive layer.", "The impulse response of a typical induction tool in a homogeneous formation is a curve that has a main lobe of finite width that spans a length of the borehole and an amplitude that is an inverse non-linear function of the formation conductivity (N.B. the unit of measurement for conductivity is mho and for borehole applications, 0.001 mho or mmho.", "Some authors use units of resistivity which are measured in ohm-meters.", "The terms are often used interchangeably).", "Although most of the signal originates from the main lobe, unwanted side lobes of non-zero amplitudes extend vertically above and beneath the main lobe.", "In thin beds of low conductivity, the unwanted contribution of the side lobes from adjacent beds that have higher conductivity, will cause the thin-bed measurements to be too high.", "That error is called the "shoulder effect".", "As before stated, the magnitude of impulse response of the induction logging tool is an inverse function of formation conductivity but that function is non-linear.", "The non-linearity is referred to as the "skin effect".", "The magnitude of the skin effect is also a complex function of the system operating frequency and coil separation.", "Various methods have been used in the prior-art borehole logging sondes to counteract the problems cited.", "For example, see U.S. Pat. No. 4,471,436, issued Sep. 11, 1984 to R. T. Schaefer et al.", "for PHASOR PROCESSING OF INDUCTION LOGS INCLUDING SHOULDER AND SKIN EFFECTS.", "Shoulder effect is reduced by generating a spatial deconvolution filter which sharpens the main lobe and reduces the side lobes when the filter is convolved with the VGF.", "The skin effect is reduced by filtering the quadrature phase component measurements according to a non-linear spatial filtering function to obtain a correction representative of the change in sonde response function as a function of the formation conductivity.", "The correction component measurements are then summed with the processed in-phase component measurement to produce a processed log measurement sans the unwanted side-lobe contributions.", "There are certain technical differences between wireline logging tools as described above and tools used in measurement-while-drilling (MWD).", "In the latter case, the transmitter and receiving coils of the tool are mounted on a highly-conductive metal mandrel to withstand the drilling stresses during operation.", "The physical configuration of the conductive mandrel and the transmitter/receiver coils requires that the coils be excited at a frequency on the order of MHz.", "This tool is thus also named as a propagated wave resistivity tool.", "Whereas the prior-art wireline tools depended upon a combination of the real and quadrature components to derive apparent conductivity, the propagated wave resistivity tool of this invention relies on the phase difference between the measured signals in the two receiver coils.", "Therefore, the way of evaluating the VGF impulse response function for MWD is different from that for wireline induction application.", "See for example MWD Resistivity Tool Response In A Layered Medium, by Q. Zhou et al.", ", Geophysics, November 1991, pp. 1738-1748.", "Also Geometric Factor and Adaptive Deconvolution of MWD-PWR Tools, by Q. Zhou et al.", ", The Log Analyst, July-August, 1992 pp. 390-398.", "SUMMARY OF THE INVENTION In accordance with this invention, a propagated wave resistivity tool measures the phase differences between the voltages induced in two receiver coils as the electromagnetic wave propagates through the formation volume to which the tool is responsive.", "The measured phase differences are averaged to determine a background phase.", "A deconvolution filter appropriate to the current position of the tool in the formation volume of interest is derived based upon the averaged value of the phase differences which may be a weighted average.", "The measured phase differences are spatially deconvolved thereby to enhance the vertical resolution of the measurements by reducing the shoulder effects.", "BRIEF DESCRIPTION OF THE DRAWINGS The novel features which are believed to be characteristic of the invention, both as to organization and methods of operation, together with the objects and advantages thereof, will be better understood from the following detailed description and the drawings wherein the invention is illustrated by way of example for the purpose of illustration and description only and are not intended as a definition of the limits of the invention: FIG. 1a illustrates an MWD logging tool;", "FIG. 1b is an electrical equivalent of two transmitter coils and two receiver coils;", "FIG. 2 shows the VGF impulse response for phase for the array of FIG. 1b, for four constant background formation conductivity values;", "FIG. 3 is a graph of phase difference as a function of resistivity (conductivity -1 ) in a homogeneous formation;", "FIG. 4 shows the vertical resolution enhancement for a sequence of formation beds.", "DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1a, there is shown the lower end 10 of an MWD tool as employed in drilling a borehole.", "The tool consists of a mandrel 10 about 6.75"", "in diameter and which is usually made of non-magnetic alloy.", "A drill bit 12 is screwed to the bottom of the mandrel in a manner well known in the art.", "Transmitter coils or antennas T 1 and T 2 are wound in suitable grooves that are 1.7 meters apart.", "Receiver coils or antennas R 1 and R 2 that are themselves spaced apart by 0.3 meter are mounted 0.7 meter from the respective transmitter antennas.", "For an MWD tool, the transmitter antennas are alternately excited at an excitation frequency of 1 MHz.", "The electromagnetic equivalent of the tool approximates a vertical magnetic dipole (VMD) as shown in FIG. 1b.", "The formation volume to which the tool is primarily responsive is the spatial interval encompassed by the receiving antennas or coils.", "The point of measurement is usually taken as the midpoint between the receiver coils or antennas.", "The propagated wave resistivity tool of this invention measures the change in phase between the voltages induced in two spaced-apart receiver antennas as an electromagnetic field, launched from a transmitter antenna, propagates through the surrounding formation between the antennas, the electromagnetic field being guided by the conductive mandrel.", "For simplicity of the mathematic expressions, one transmitter and one receiver will be assumed.", "In an azimuthally symmetric formation, it can be shown that the geometric factor for phase and amplitude is given by: ##EQU1## where: E P (r,r T )=the electric field in the azimuthal direction for a source at r T and observation point at r, E P (r R ,r T )=the electric field in the azimuthal direction for a source at r T and receiver point at r R , G(r R ,r)=Green's function relating the eddy current at r to the field at r R , and C=a normalizing constant that depends upon the tool geometry and is given by C=(ωμL.", "sup[.", "].2)/2.", "(2) Under the dipole approximation of the coils, ##EQU2## In the above formulations, L=coil separation, k O 2 =iωμσ O , μ=magnetic permeability of formation in air, σ O =formation background conductivity, ω=angular frequency.", "The vertical geometric factor g v for phase can be derived by integrating the imaginary part of g(r;", "r R , r T ) from equation (1) over the radius from zero to infinity: ##EQU3## FIG. 2 is the phase impulse response for a two transmitter, two receiver system for four different formation conductivities, σ O =0.01, 0.10, 0.32 and 3.16, represented by curves 14, 16, 18 and 20 respectively.", "From the response curves, one can appreciate that the response is broader at low conductivities than at high conductivity.", "Decreased vertical spatial resolution results for a resistive formation because the electromagnetic field penetrates further into more resistive formations than in a conductive formation.", "With the VGF known from the impulse response curves of FIG. 2, it becomes possible to enhance and to reshape the tool responses to provide better vertical resolution and symmetric response characteristics.", "However, because the VGFs are dependent upon the background conductivity and the phase measurement is non-linear with respect to the formation conductivity, an adaptive deconvolution method is required.", "Equation (4) provides the VGF impulse response function necessary for deconvolution.", "In conventional induction logging, the apparent conductivity is derived by dividing the measured voltage by a normalizing constant.", "The nonlinear nature of the problem at high conductivity is corrected by application of a skin effect correction.", "In the propagated wave resistivity tool of this invention, the conversion from measured phase difference to apparent conductivity is made with the aid of the computed homogeneous formation phase response curve shown in FIG. 3. The nonlinear response in a homogeneous formation is inherently reflected in the conversion.", "The phase difference will be deconvolved to provide the argument entry for determining apparent conductivity according to the curve in FIG. 3. It will be assumed that conductivity is a function of z (depth) only and the tool will be assumed to be perpendicular to the layer surfaces.", "The perturbation of the phase difference θ S from θ O which would exist in a particular background conductivity σ O can be shown to be ##EQU4## In the Fourier domain, (5) becomes Θ=CΣG.", "sub.", "V (6) where Θ, Σ and G v are the Fourier transforms of 8 s , θ S ,[σ(z)-σ O ] and g v respectively.", "Ideally, the conductivity can be derived from Σ=Θ/(CG.", "sub.", "v).", "(7) Formulation (7) turns out to be unstable due to physical tool-measurement limitations.", "Preferably, a suitable low-pass filter such as Gaussian filter function, T, but not limited thereto, is introduced to band-limit the deconvolution as follows: ##EQU5## The half-width of the filter function is adjusted based upon prior experience in the region under study, to control the vertical resolution enhancement.", "In (8) the adaptive deconvolution filter function in the Fourier domain is T/G v .", "Its inverse transform is the space domain deconvolution filter.", "In operation, as the tool is drawn through a borehole drilled into a formation of interest, the transmitters are alternately excited to transmit an electromagnetic wave past the receiver coils.", "The phase difference between the voltages induced in the receiver antennas are measured at a plurality of different levels and recorded by a suitable recording means of any well known type (not shown).", "A plurality of phase VGF's or impulse response curves are precalculated for a range of conductivities that are expected to be encountered in earth formations.", "Typical curves such as shown in FIG. 2 may be generated for a plurality of different estimated conductivities.", "A corresponding plurality of exemplary deconvolution filters are created from the precalculated phase impulse response functions.", "Next, the measured phase differences are averaged over a spatial interval corresponding to the formation volume in which the tool is currently located and to which the tool is responsive to provide an average background phase value within the formation volume of interest.", "Preferably the measurements are weighted prior to averaging by application of weighting coefficients derived from some desired function that may be Gaussian but is not limited thereto.", "A new deconvolution filter that is appropriate to the current formation volume is computed by interpolating between the plurality of exemplary deconvolution filters.", "The current phase measurements are deconvolved with the aid of the new deconvolution filter.", "Shaping operators such as a Hamming or a Blackman window may be applied to the data set to minimize side lobes.", "The process is repeated for other levels in the borehole.", "The deconvolution process is adapted to the changing parameters along the borehole by choosing an appropriate deconvolution filter that depends upon the weighted conductivity around each depth level of interest.", "FIG. 4 is a showing of the vertical resolution enhancement for a model of a sequence of formation beds.", "The coordinates are a linear vertical depth scale vs.", "apparent resistivity in ohm-meters on a logarithmic scale.", "The solid lines 22 represent the model (true) formation layers;", "the short dashed lines 26 depict the raw data;", "the broken lines 24 are the results of applying the teachings of this invention.", "This invention has been described with a certain specificity by way of example but not by way of limitation.", "Those skilled in the art will consider other techniques for performing the disclosed process which will fall within the scope and spirit of this invention which is limited only by the appended claims." ]
BACKGROUND OF THE INVENTION The present invention relates to an automatic error detection and correction system suited for differential phase-shift-keying (DPSK) data transmission systems. To adapt an error correction system to a DPSK system, the structure illustrated in FIG. 1 is conventionally employed. In FIG. 1, after check digits have been added at an error correcting encoder 1 to data to be transmitted, the data are differentially encoded in a differential encoder 3 included in a modulator unit 2 so that they are modulated onto a carrier wave at a modulator 4 and then transmitted to a transmission (or storage) medium 5. The data received through the transmission medium 5 are demodulated first by a demodulator 7 in a demodulator unit 6. After the data have been differentially decoded in a differential decoder 8 of the modulator unit 6, the errors introduced during the transmission are corrected in an error correcting decoder 9 to restore correct transmission data. However, if one digit error (corresponding to one phase-encoded data) is introduced in the transmission medium 5, the error is expanded in the differential decoder 8 with the result that errors of two successive phase-encoded data are given to the error correcting decoder 9. The structure of FIG. 1 therefore requires an encoder and a decoder capable of correcting more errors than those introduced during the transmission through the transmission medium 5, and unavoidably complicates the encoder and decoder. For details of such a prior art shown in FIG. 1, reference is made to FIG. 5 of the article by G. David Forney, Jr., and Edward K. Bower, entitled "A High-Speed Sequential Decoder: Prototype Design and Test," IEEE Transactions on Communication Technology, Vol. COM-19, No. 5, October issue, 1971, pp. 821-824. To avoid such a disadvantage, a modified structure illustrated in FIG. 6(b) of the Forney, Jr. et al. article has been proposed. Such structure is shown schematically in FIG. 2 of the accompanying drawings. The error correcting encoder 1 and the differential encoder 3 are interchanged in sequence and the error correcting decoder 9 and the differential decoder 8 are also interchanged so that the error correcting and decoding can be carried out so that the errors introduced in the transmission medium 5 are not expanded. However, in this modified structure, the error correction must be performed before carrying out the differential decoding. The error correction therefore must be carried out under such state that there is no coincidence in phase references between the transmitter and the receiver. To solve this problem, another structure effectively adaptable to a quadri-phase-shift-keying (QPSK) system has been proposed in FIG. 7(a) of the Forney, Jr. et al. article. Its simplified structure is shown in FIG. 3 of the attached drawings. The feature of the structure lies in employing two binary error correcting codes, independently. In more detail, one phase (-encoded) data is represented by 2 bits as shown by the two input and output lines. Like reference numerals denote like structural elements in FIG. 1. However, either structure of FIG. 2 or FIG. 3 cannot be adopted if the error correcting encoder 1 and the modulator unit 2, and the error correcting decoder 9 and the demodulator unit 6 are not formed in the same structural units, respectively. Even if they are formed in the same structural units, said units 2 and 6 of FIG. 1 need to be modified to the structure of FIG. 2 or FIG. 3. This prevents various problems in design changes, which seems to be impossible as a practical matter. SUMMARY OF THE INVENTION An object of the present invention is therefore to provide a novel error correcting system for DPSK which is free from the above mentioned disadvantages of the prior art systems. The present system is composed of: an encoder unit including a differential encoder, an error correcting encoder and a differential decoder; a decoder unit including a differential encoder, an error correcting decoder and a differential decoder; and a transmission or storage medium disposed between said respective units and including DPSK modulator and demodulator. BRIEF DESCRIPTION OF THE DRAWINGS Now the present invention will be described in greater detail in conjunction with the accompanying drawings, in which: FIGS. 1, 2 and 3 are block diagrams of conventional error correcting systems; FIG. 4 is a block diagram of an embodiment of the present invention; FIG. 5 is a block diagram of a differential encoder; FIG. 6 is a block diagram of a differential decoder; and FIG. 7 is a block diagram showing the embodiment as applied to a QPSK system. DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 4, like reference numerals denote like structural elements shown in FIG. 1, with the primed ones denoting the corresponding structural elements on the receiver side. Reference numerals 10 and 13 designate an encoder unit and a decoder unit, respectively, which are newly proposed in the present invention. As is well-known, when the phase positions 0°, a°, 2a°, . . . , and (m-1)a° (where a°=360°/M) in an M-ary DPSK system are represented by 0, 1, 2, . . . , and (M-1), the differential encoder 3 and differential decoder 8 can be shown as in FIGS. 5 and 6, respectively. In FIGS. 5 and 6, reference numerals 16 and 16' designate registers for storing one phase datum, and numerals 17 and 17' respectively designate a modulo-M adder and a modulo-M subtractor. FIGS. 5 and 6 show that the differential encoder and the differential decoder function to perform mutually reverse transformations. Now with reference to FIG. 4, a transmission data sequence is differentially encoded first by a differential encoder 3 in an encoder unit 10, and then it is added with check data in an error correcting encoder 1. After it has been subjected to the transformation of differential decoding in a differential decoder 8, it is transmitted to a modulator unit 2. The data sequence is, similarly to the system shown in FIG. 1, transmitted from the modulator unit 2, through a transmission medium 5 and a demodulator unit 6 to a decoder unit 13. In some cases, the modulator unit 2, transmission medium 5 and demodulator unit 6 are called a transmission medium including DPSK modulator and demodulator. If no error is introduced in the transmission medium 5, the input data sequence given to the modulator unit 2 and the output data sequence given from the demodulator unit 6 are exactly idential. However, if an error is introduced, a register in a differential decoder 8' for storing the above-mentioned one digit causes the one digit to affect the next clock with the result that the error is doubled. A differential encoder 3" of the decoder unit 13 which has received the data sequence having the error doubled, restores the received data sequence to the previous data sequence which is inputed to the differential decoder 8'. However, at this moment, attention should be paid to the following points. In the differential decoder 8', if the input data sequence a 0 , a 1 , a 2 , . . . , a n , . . . is represented by A(D)=a 0 +a 1 D+a 2 D 2 + . . . +a n D n + . . . , the output data sequence b 0 , b 1 , b 2 , . . . , b n , . . . is represented by B(D)=b 0 +b 1 D+b 2 D 2 + . . . +b n D n + . . . , and the initial data (that is, the data stored initially in said register for storing one phase data) is represented by c, then, the following relationship is estabilshed as will be apparent from FIG. 6: B(D)=A(D)·(1-D)-c ((mod M)) (1) On the other hand, if the input data sequence, output data sequence and initial data are represented in the differential encoder 3" by E(D), F(D) and g, respectively, in the same manner as the case of the differential decoder 8', the following relationship is established by the structure of FIG. 5: F(D)=E(D)/(1-D)+g/(1-D) (mod M) (2) Therefore, if the initial data in the differential decoder 8' and differential encoder 3", respectively, are represented by c and g, the output data sequence F(D) obtained after the data sequence A(D) has been input to the differential decoder 8' and its output data sequence has been in itself input to the differential encoder 3", can be represented in the following form: ##EQU1## It is seen that the output data sequence F(D) given from the differential encoder 3" is a data sequence formed by always adding in modulo M the initial data difference (g-c) to the input data sequence A(D) for the differential decoder 8', and that the phase references are different by the amount of (g-c) between the input and output data sequences A(D) and F(D). Except for the amount of the initial data difference, the respective data sequences are equal to each other, with the erroneous phase-encoded data constituting the only erroneous data introduced in the transmission medium. Thus, the errors are never expanded in the present system. For the same reasons, the output data sequence given from the differential encoder 3" is a data sequence formed by always adding in modulo M the amount of the initial data difference to the input data sequence for the differential decoder 8. In other words, the output data sequence given from the error correcting encoder 1 and the input data sequence given to the error correcting decoder 9 are, similarly to the prior art system shown in FIG. 2 or 3, different only in the phase reference, and except for the amount of the difference, the respective data sequences are different only with respect to the erroneous data introduced in the transmission medium 5 without expansion of the errors, and are exactly the same data sequences with respect to the remaining data. Therefore, with respect to the error correcting codes, it can be assumed as in the case of FIGS. 2 and 3 that the conventional codes usable even without the absence of the coincidence of the phase references are employed. Then, the error correcting decoder 9 is required to correct only the erroneous data produced in the transmission medium. The difference in the phase references can be removed by disposing the differential encoder 3 and the differential decoder 8", respectively, outside of the error correcting encoder 1 and the error correcting decoder 9. More particularly, when the input and output data sequences and initial data of the differential decoder 8" are represented respectively by A(D), B(D) and c, and when the input and output data sequences and initial data of the differential encoder 3 are represented respectively by E(D), F(D) and g, as discussed previously, equations (1) and (2) are established. In addition, if the difference in the phase references between the input data sequence A(D) and the input data sequence E(D) is represented by h, the following relationship is established: ##EQU2## From equations (1), (2) and (3), the following equation is satisfied: ##EQU3## Consequently, it can be readily seen that the output data sequence B(D) given from the differential decoder 8" is entirely identical to the input data sequence E(D) for the differential encoder 3 except for the data at the very initial time point, and the difference h in the phase references is removed. Therefore, so long as the errors introduced in the transmission medium 5 come within the error correcting capability of the employed error correcting codes, the input data sequence given to the encoder unit 10 and the output data sequence given from the decoder unit 13 are exactly identical data sequences except for the data at the very initial time point. Now, as one example of the utilization of the conventional codes usable even in the absence of the coincidence of the phase references, two binary error correcting codes employed independently in the DPSK system will be described in detail in connection to FIG. 7. In FIG. 7, like reference numerals denote like structural elements shown in FIG. 3. Each of the respective phase-encoded data 0, 1, 2 and 3 in the DPSK system can be represented as a 2-bit data, and normally at the input and output of the modem the data are handled as represented in the form of the so-called Gray code. More particularly, the respective phase-encoded data of 0, 1, 2 and 3 are handled as represented by 2 bits in the form of 00, 01, 11 and 10, respectively. Therefore, it is assumed that in the encoder unit 10' and the decoder unit 13' also the respective phase-encoded data 0, 1, 2 and 3 are represented in the form of the Gary code. In this case, the adders and subtractors of modulo 4 contained in the differential encoders 3, 3' and 3" and in the differential decoders 8, 8' and 8" are adapted to output the results of the calculation according to the following calculation tables 1 and 2. TABLE 1______________________________________PHASE-ENCODEDDATA b 0 1 2 3PHASE-ENCODEDDATA a 00 01 11 10______________________________________0 00 00 01 11 101 01 01 11 10 002 11 11 10 00 013 10 10 00 01 11 a + b (mod 4)______________________________________ TABLE 2______________________________________PHASE-ENCODEDDATA b 0 1 2 3PHASE-ENCODEDDATA a 00 01 11 10______________________________________0 00 00 10 11 011 01 01 00 10 112 11 11 01 00 103 10 10 11 01 00 a - b (mod 4)______________________________________ In FIG. 7, the input bit sequences fed to the error correcting encoders 1"-1 and 1"-2 are represented by P'i and Q'i, respectively, and the output bit sequences after the check bits have been added are represented by Pi and Qi, respectively, Then, the input bit sequences given to the error correcting decoders 9"-1 and 9"-2, respectively, will vary depending upon the difference between the initial data given to the differential decoder 8 and the differential encoder 3", respectively, and they can be represented as shown in the following table 3. This table 3 can be easily derived by carrying out the addition in modulo 4 of any arbitary data represented by 2 bits and the above-mentioned difference between the initial data i (=0, 1, 2, 3) assuming that M=4 is satisfied, and by checking how the 2 bits are varied on the basis of table 1. In table 3, an asterisk (*) represents that the sequence is a sequence having some errors added only on the transmission medium 5, while a bar (-) represents that the sequence is a sequence having its every data bit inverted. TABLE 3______________________________________Difference between theinitial phase-encoded Input to Input todata the decoder 9"-1 the decoder 9"-2______________________________________0 Pi* Qi*1 Qi* --Pi*2 --Pi* --Qi*3 --Qi* Pi*______________________________________ As will be seen from table 3, the input bit sequences given to the error correcting decoders 9"-1 and 9"-2 are any one of Pi*, Pi*, Qi* and Qi*. However, in the case of employing the conventional binary error correcting codes, if the errors introduced in the transmission medium 5 come within the error correcting capability, the above-mentioned input bit sequences Pi*, Pi*, Qi* and Qi* become Pi, Pi, Qi and Qi, respectively, after the decoding operation. As described above, P'i and Q'i represent the input bit sequences fed to the error correcting encoders 1"-1 and 1"-2. Therefore, assuming that the output bit sequences given from the error correcting decoders 9"-1 and 9"-2 are the bit sequences Q'i and P'i free of the check digits, the output data sequences obtained from the error correcting decoders 9"-1 and 9"-2 are, the data sequences obtained by adding in modulo 4, +3 to all the data in the input data sequences for the error correcting encoders 1"-1 and 1"-2 from the tables 1 and 3. Since this difference in the phase reference can be removed by the differential encoder 3 and the differential decoder 8" as mentioned previously, the input data sequence to the encoder unit 10' becomes entirely identical to the output data sequence given from the decoder unit 13'. This fact is similarly applied to the case where the output bit sequences given from the error correcting decoders 9"-1 and 9"-2 are a different combination of bit sequences. With regard to the error correcting encoders 1"-1 and 1"-2 and error correcting decoders 9"-1 and 9"-2 of FIG. 7, reference is made to FIG. 5.05 on page 125 and FIG. 5.03 or page 123, respectively, of the book entitled Algebraic Coding Theory by Elwyn R. Berlekamp, published in 1968 by McGraw-Hill, Inc. As described in detail above, the present error correcting system provides a very efficient system while allowing even the conventional DPSK modulator and demodulator to be utilized without any structural changes. While the present invention has been described in detail above as applied specifically to the QPSK system, it will be easily understood that the present invention can provide a similarly effective error correction system for the conventional M-ary error correcting codes based on the modulo-M calculation.
An error correcting system for DPSK is comprised of an encoder unit, a decoder unit and a transmission medium disposed between the encoder and decoder units. The encoder includes a differential encoder for differentially encoding an input data sequence, an error correcting encoder for adding a check digit sequence to the differentially encoded data sequence, and a differential decoder for differentially decoding the data sequence added with the check digit sequence. The decoder unit includes a differential encoder for differentially encoding a received data sequences, an error correcting decoder for correcting error digits contained in the differentially encoded received data sequence, and a differential decoder for differentially decoding the output data sequence from the error correcting decoder. The transmission medium typically includes a differentially encoded phase-shifting-keying modulator unit and a differentially encoded phase-shift-keying demodulator unit.
Summarize the key points of the given patent document.
[ "BACKGROUND OF THE INVENTION The present invention relates to an automatic error detection and correction system suited for differential phase-shift-keying (DPSK) data transmission systems.", "To adapt an error correction system to a DPSK system, the structure illustrated in FIG. 1 is conventionally employed.", "In FIG. 1, after check digits have been added at an error correcting encoder 1 to data to be transmitted, the data are differentially encoded in a differential encoder 3 included in a modulator unit 2 so that they are modulated onto a carrier wave at a modulator 4 and then transmitted to a transmission (or storage) medium 5.", "The data received through the transmission medium 5 are demodulated first by a demodulator 7 in a demodulator unit 6.", "After the data have been differentially decoded in a differential decoder 8 of the modulator unit 6, the errors introduced during the transmission are corrected in an error correcting decoder 9 to restore correct transmission data.", "However, if one digit error (corresponding to one phase-encoded data) is introduced in the transmission medium 5, the error is expanded in the differential decoder 8 with the result that errors of two successive phase-encoded data are given to the error correcting decoder 9.", "The structure of FIG. 1 therefore requires an encoder and a decoder capable of correcting more errors than those introduced during the transmission through the transmission medium 5, and unavoidably complicates the encoder and decoder.", "For details of such a prior art shown in FIG. 1, reference is made to FIG. 5 of the article by G. David Forney, Jr., and Edward K. Bower, entitled "A High-Speed Sequential Decoder: Prototype Design and Test,"", "IEEE Transactions on Communication Technology, Vol. COM-19, No. 5, October issue, 1971, pp. 821-824.", "To avoid such a disadvantage, a modified structure illustrated in FIG. 6(b) of the Forney, Jr. et al.", "article has been proposed.", "Such structure is shown schematically in FIG. 2 of the accompanying drawings.", "The error correcting encoder 1 and the differential encoder 3 are interchanged in sequence and the error correcting decoder 9 and the differential decoder 8 are also interchanged so that the error correcting and decoding can be carried out so that the errors introduced in the transmission medium 5 are not expanded.", "However, in this modified structure, the error correction must be performed before carrying out the differential decoding.", "The error correction therefore must be carried out under such state that there is no coincidence in phase references between the transmitter and the receiver.", "To solve this problem, another structure effectively adaptable to a quadri-phase-shift-keying (QPSK) system has been proposed in FIG. 7(a) of the Forney, Jr. et al.", "article.", "Its simplified structure is shown in FIG. 3 of the attached drawings.", "The feature of the structure lies in employing two binary error correcting codes, independently.", "In more detail, one phase (-encoded) data is represented by 2 bits as shown by the two input and output lines.", "Like reference numerals denote like structural elements in FIG. 1. However, either structure of FIG. 2 or FIG. 3 cannot be adopted if the error correcting encoder 1 and the modulator unit 2, and the error correcting decoder 9 and the demodulator unit 6 are not formed in the same structural units, respectively.", "Even if they are formed in the same structural units, said units 2 and 6 of FIG. 1 need to be modified to the structure of FIG. 2 or FIG. 3. This prevents various problems in design changes, which seems to be impossible as a practical matter.", "SUMMARY OF THE INVENTION An object of the present invention is therefore to provide a novel error correcting system for DPSK which is free from the above mentioned disadvantages of the prior art systems.", "The present system is composed of: an encoder unit including a differential encoder, an error correcting encoder and a differential decoder;", "a decoder unit including a differential encoder, an error correcting decoder and a differential decoder;", "and a transmission or storage medium disposed between said respective units and including DPSK modulator and demodulator.", "BRIEF DESCRIPTION OF THE DRAWINGS Now the present invention will be described in greater detail in conjunction with the accompanying drawings, in which: FIGS. 1, 2 and 3 are block diagrams of conventional error correcting systems;", "FIG. 4 is a block diagram of an embodiment of the present invention;", "FIG. 5 is a block diagram of a differential encoder;", "FIG. 6 is a block diagram of a differential decoder;", "and FIG. 7 is a block diagram showing the embodiment as applied to a QPSK system.", "DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 4, like reference numerals denote like structural elements shown in FIG. 1, with the primed ones denoting the corresponding structural elements on the receiver side.", "Reference numerals 10 and 13 designate an encoder unit and a decoder unit, respectively, which are newly proposed in the present invention.", "As is well-known, when the phase positions 0°, a°, 2a°, .", ", and (m-1)a° (where a°=360°/M) in an M-ary DPSK system are represented by 0, 1, 2, .", ", and (M-1), the differential encoder 3 and differential decoder 8 can be shown as in FIGS. 5 and 6, respectively.", "In FIGS. 5 and 6, reference numerals 16 and 16'", "designate registers for storing one phase datum, and numerals 17 and 17'", "respectively designate a modulo-M adder and a modulo-M subtractor.", "FIGS. 5 and 6 show that the differential encoder and the differential decoder function to perform mutually reverse transformations.", "Now with reference to FIG. 4, a transmission data sequence is differentially encoded first by a differential encoder 3 in an encoder unit 10, and then it is added with check data in an error correcting encoder 1.", "After it has been subjected to the transformation of differential decoding in a differential decoder 8, it is transmitted to a modulator unit 2.", "The data sequence is, similarly to the system shown in FIG. 1, transmitted from the modulator unit 2, through a transmission medium 5 and a demodulator unit 6 to a decoder unit 13.", "In some cases, the modulator unit 2, transmission medium 5 and demodulator unit 6 are called a transmission medium including DPSK modulator and demodulator.", "If no error is introduced in the transmission medium 5, the input data sequence given to the modulator unit 2 and the output data sequence given from the demodulator unit 6 are exactly idential.", "However, if an error is introduced, a register in a differential decoder 8'", "for storing the above-mentioned one digit causes the one digit to affect the next clock with the result that the error is doubled.", "A differential encoder 3"", "of the decoder unit 13 which has received the data sequence having the error doubled, restores the received data sequence to the previous data sequence which is inputed to the differential decoder 8'.", "However, at this moment, attention should be paid to the following points.", "In the differential decoder 8', if the input data sequence a 0 , a 1 , a 2 , .", ", a n , .", "is represented by A(D)=a 0 +a 1 D+a 2 D 2 + .", "+a n D n + .", ", the output data sequence b 0 , b 1 , b 2 , .", ", b n , .", "is represented by B(D)=b 0 +b 1 D+b 2 D 2 + .", "+b n D n + .", ", and the initial data (that is, the data stored initially in said register for storing one phase data) is represented by c, then, the following relationship is estabilshed as will be apparent from FIG. 6: B(D)=A(D)·(1-D)-c ((mod M)) (1) On the other hand, if the input data sequence, output data sequence and initial data are represented in the differential encoder 3"", "by E(D), F(D) and g, respectively, in the same manner as the case of the differential decoder 8', the following relationship is established by the structure of FIG. 5: F(D)=E(D)/(1-D)+g/(1-D) (mod M) (2) Therefore, if the initial data in the differential decoder 8'", "and differential encoder 3", respectively, are represented by c and g, the output data sequence F(D) obtained after the data sequence A(D) has been input to the differential decoder 8'", "and its output data sequence has been in itself input to the differential encoder 3", can be represented in the following form: ##EQU1## It is seen that the output data sequence F(D) given from the differential encoder 3"", "is a data sequence formed by always adding in modulo M the initial data difference (g-c) to the input data sequence A(D) for the differential decoder 8', and that the phase references are different by the amount of (g-c) between the input and output data sequences A(D) and F(D).", "Except for the amount of the initial data difference, the respective data sequences are equal to each other, with the erroneous phase-encoded data constituting the only erroneous data introduced in the transmission medium.", "Thus, the errors are never expanded in the present system.", "For the same reasons, the output data sequence given from the differential encoder 3"", "is a data sequence formed by always adding in modulo M the amount of the initial data difference to the input data sequence for the differential decoder 8.", "In other words, the output data sequence given from the error correcting encoder 1 and the input data sequence given to the error correcting decoder 9 are, similarly to the prior art system shown in FIG. 2 or 3, different only in the phase reference, and except for the amount of the difference, the respective data sequences are different only with respect to the erroneous data introduced in the transmission medium 5 without expansion of the errors, and are exactly the same data sequences with respect to the remaining data.", "Therefore, with respect to the error correcting codes, it can be assumed as in the case of FIGS. 2 and 3 that the conventional codes usable even without the absence of the coincidence of the phase references are employed.", "Then, the error correcting decoder 9 is required to correct only the erroneous data produced in the transmission medium.", "The difference in the phase references can be removed by disposing the differential encoder 3 and the differential decoder 8", respectively, outside of the error correcting encoder 1 and the error correcting decoder 9.", "More particularly, when the input and output data sequences and initial data of the differential decoder 8"", "are represented respectively by A(D), B(D) and c, and when the input and output data sequences and initial data of the differential encoder 3 are represented respectively by E(D), F(D) and g, as discussed previously, equations (1) and (2) are established.", "In addition, if the difference in the phase references between the input data sequence A(D) and the input data sequence E(D) is represented by h, the following relationship is established: ##EQU2## From equations (1), (2) and (3), the following equation is satisfied: ##EQU3## Consequently, it can be readily seen that the output data sequence B(D) given from the differential decoder 8"", "is entirely identical to the input data sequence E(D) for the differential encoder 3 except for the data at the very initial time point, and the difference h in the phase references is removed.", "Therefore, so long as the errors introduced in the transmission medium 5 come within the error correcting capability of the employed error correcting codes, the input data sequence given to the encoder unit 10 and the output data sequence given from the decoder unit 13 are exactly identical data sequences except for the data at the very initial time point.", "Now, as one example of the utilization of the conventional codes usable even in the absence of the coincidence of the phase references, two binary error correcting codes employed independently in the DPSK system will be described in detail in connection to FIG. 7. In FIG. 7, like reference numerals denote like structural elements shown in FIG. 3. Each of the respective phase-encoded data 0, 1, 2 and 3 in the DPSK system can be represented as a 2-bit data, and normally at the input and output of the modem the data are handled as represented in the form of the so-called Gray code.", "More particularly, the respective phase-encoded data of 0, 1, 2 and 3 are handled as represented by 2 bits in the form of 00, 01, 11 and 10, respectively.", "Therefore, it is assumed that in the encoder unit 10'", "and the decoder unit 13'", "also the respective phase-encoded data 0, 1, 2 and 3 are represented in the form of the Gary code.", "In this case, the adders and subtractors of modulo 4 contained in the differential encoders 3, 3'", "and 3"", "and in the differential decoders 8, 8'", "and 8"", "are adapted to output the results of the calculation according to the following calculation tables 1 and 2.", "TABLE 1______________________________________PHASE-ENCODEDDATA b 0 1 2 3PHASE-ENCODEDDATA a 00 01 11 10______________________________________0 00 00 01 11 101 01 01 11 10 002 11 11 10 00 013 10 10 00 01 11 a + b (mod 4)______________________________________ TABLE 2______________________________________PHASE-ENCODEDDATA b 0 1 2 3PHASE-ENCODEDDATA a 00 01 11 10______________________________________0 00 00 10 11 011 01 01 00 10 112 11 11 01 00 103 10 10 11 01 00 a - b (mod 4)______________________________________ In FIG. 7, the input bit sequences fed to the error correcting encoders 1"-1 and 1"-2 are represented by P'i and Q'i, respectively, and the output bit sequences after the check bits have been added are represented by Pi and Qi, respectively, Then, the input bit sequences given to the error correcting decoders 9"-1 and 9"-2, respectively, will vary depending upon the difference between the initial data given to the differential decoder 8 and the differential encoder 3", respectively, and they can be represented as shown in the following table 3.", "This table 3 can be easily derived by carrying out the addition in modulo 4 of any arbitary data represented by 2 bits and the above-mentioned difference between the initial data i (=0, 1, 2, 3) assuming that M=4 is satisfied, and by checking how the 2 bits are varied on the basis of table 1.", "In table 3, an asterisk (*) represents that the sequence is a sequence having some errors added only on the transmission medium 5, while a bar (-) represents that the sequence is a sequence having its every data bit inverted.", "TABLE 3______________________________________Difference between theinitial phase-encoded Input to Input todata the decoder 9"-1 the decoder 9"-2______________________________________0 Pi* Qi*1 Qi* --Pi*2 --Pi* --Qi*3 --Qi* Pi*______________________________________ As will be seen from table 3, the input bit sequences given to the error correcting decoders 9"-1 and 9"-2 are any one of Pi*, Pi*, Qi* and Qi*.", "However, in the case of employing the conventional binary error correcting codes, if the errors introduced in the transmission medium 5 come within the error correcting capability, the above-mentioned input bit sequences Pi*, Pi*, Qi* and Qi* become Pi, Pi, Qi and Qi, respectively, after the decoding operation.", "As described above, P'i and Q'i represent the input bit sequences fed to the error correcting encoders 1"-1 and 1"-2.", "Therefore, assuming that the output bit sequences given from the error correcting decoders 9"-1 and 9"-2 are the bit sequences Q'i and P'i free of the check digits, the output data sequences obtained from the error correcting decoders 9"-1 and 9"-2 are, the data sequences obtained by adding in modulo 4, +3 to all the data in the input data sequences for the error correcting encoders 1"-1 and 1"-2 from the tables 1 and 3.", "Since this difference in the phase reference can be removed by the differential encoder 3 and the differential decoder 8"", "as mentioned previously, the input data sequence to the encoder unit 10'", "becomes entirely identical to the output data sequence given from the decoder unit 13'.", "This fact is similarly applied to the case where the output bit sequences given from the error correcting decoders 9"-1 and 9"-2 are a different combination of bit sequences.", "With regard to the error correcting encoders 1"-1 and 1"-2 and error correcting decoders 9"-1 and 9"-2 of FIG. 7, reference is made to FIG. 5.05 on page 125 and FIG. 5.03 or page 123, respectively, of the book entitled Algebraic Coding Theory by Elwyn R. Berlekamp, published in 1968 by McGraw-Hill, Inc. As described in detail above, the present error correcting system provides a very efficient system while allowing even the conventional DPSK modulator and demodulator to be utilized without any structural changes.", "While the present invention has been described in detail above as applied specifically to the QPSK system, it will be easily understood that the present invention can provide a similarly effective error correction system for the conventional M-ary error correcting codes based on the modulo-M calculation." ]
BACKGROUND 1. Technical Field The present disclosure relates to devices, and particularly to a device using a supporting mechanism. 2. Description of Related Art Hand-held electronic devices, such as PDAs, MP3s, and mobile phones, for example, are widely used. However, most of these hand-held electronic devices do not have a supporting mechanism. When a hand-held electronic devices are used to watch movies or read e-books, the users need to physically hold the device, which is inconvenient. Therefore, there is room for improvement in the art. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a device having a supporting mechanism in accordance with an embodiment. FIG. 2 is a partially enlarged view of the portion II of the device of FIG. 1 . FIG. 3 is a cross-sectional view of FIG. 1 . FIG. 4 is a perspective view showing the device of FIG. 3 after the supporting mechanism has been turned through a quarter of a circle. FIG. 5 is a perspective view showing the device of FIG. 1 supported in another orientation. DETAILED DESCRIPTION The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one. Referring to FIG. 1 , a device 100 in accordance with an embodiment is shown. The device 100 includes a main body 10 and a supporting mechanism 20 mounted to the main body 10 . The main body 10 may be an electronic device or may be the shell of an electronic device. In the embodiment, the main body 10 is the shell of an electronic device 200 (see FIG. 4 ). The electronic device 200 may be a mobile-phone, a personal digital assistant (PDA), PSP and other hand-held electronic devices. The supporting mechanism 20 operates to support the main body 10 in a number of different orientations such as sideways or vertically. The main body 10 is substantially rectangular, and includes a back wall 110 , a front wall 120 , and first sidewalls 130 and second sidewalls 140 . The front wall 120 defines a receiving space 122 (see FIG. 3 ) for receiving the electronic device 200 . The back wall 110 recesses to form a receiving portion 150 (see FIG. 3 ), and further defines a U-shaped slot 160 communicating with the receiving portion 150 . Referring also to FIG. 2 , the supporting mechanism 20 is mounted to the back wall 110 of the main body 10 , and includes a rotating member 23 rotatably coupled to the back wall 110 , a supporting member 25 rotatably coupled to the rotating member 23 , a post 27 and a stopping member 29 . The supporting member 25 is substantially U-shaped and matches the U-shaped slot 160 . The supporting member 25 is made of metal, and is capable of being elastically deformed. The supporting member 25 includes a cylindrical supporting portion 250 and two arms 251 extending from the supporting portion 250 . The proximate ends of the arms 251 are cranked away from each other to form two axially-aligned pivoting rods 252 (see FIG. 3 ). The two pivoting rods 252 are substantially parallel to the supporting portion 250 . The rotating member 23 is substantially U-shaped, and is rotatably received in the receiving portion 150 . The rotating member 23 includes a base 232 and two extending portions 234 respectively extending from two opposite ends of the base 232 . Referring to FIG. 3 , the middle of the base 232 defines a substantially round recess 2327 . The bottom of the recess 2327 further defines a through hole 2323 extending through the base 232 . The ends of the extending portions 234 adjacent to the base 232 respectively define a round hole 2342 . The two round holes 2342 receive and hold captive the pivoting rods 252 , such that the supporting member 25 is rotatably coupled to the rotating member 23 . The internal sides of the extending portions 234 define a plurality of limiting grooves 2341 . The limiting grooves 2341 extend in several radial directions. When the supporting member 25 is rotated relative to the rotating member 23 , the limiting grooves 2341 operate to position the supporting member 25 in different positions. The post 27 is fixed to the bottom of the receiving portion 150 , and includes a head portion 272 and a cylindrical portion 274 (see FIG. 3 ). The diameter of the head portion 272 is substantially less than the size of the recess 2327 , but is greater than the size of the through hole 2323 . The diameter of the cylindrical portion 274 is almost the same as the size of the through hole 2323 , such that friction is present to hinder the smooth and free rotation of the rotating member 23 . The cylindrical portion 274 extends through the recess 2327 and the through hole 2323 and is fixed to the bottom of the receiving portion 150 , whereby the rotating member 23 is rotatably coupled to the back wall 110 . The distance between the head portion 272 and the bottom of the receiving portion 150 is greater than the distance between the bottom of the recess 2327 and the bottom of the receiving portion 150 , thus, a clearance 2328 is defined between the head portion 272 and the bottom of the recess 2327 to allow the rotating member 23 to move a certain distance along the cylindrical portion 274 . The stopping member 29 is fixed to the back wall 110 , and is arranged adjacent to the receiving portion 150 . A portion of the stopping member 29 forms a cutout 292 . The cutout 292 includes a first wall 294 perpendicular to the first sidewalls 130 and a second wall 296 perpendicular to the first wall 294 . When the rotating member 23 rotates around the post 27 , the first wall 294 stops the rotating member 23 in a first position with the extending portion 234 parallel to the second sidewalls 140 , and the second sidewall 296 stops the rotating member in a second position perpendicular to the first position. The supporting mechanism 20 further includes a limiting member 31 (see FIG. 3 ). The limiting member 31 is integral with or secured to the bottom of the receiving portion 150 , and is used to provide a barrier to prevent the rotating member 23 from moving when the rotating member 23 is located in one of the first or second positions. In assembly, first, the post 27 is inserted through the recess 2327 and the through hole 2323 , and is fixed to the bottom of the receiving portion 150 , thus, the rotating member 23 is rotatably coupled to the main body 20 . Second, the pivoting rods 252 are manipulated into the round holes 2342 , such that the supporting member 25 is rotatably coupled to the rotating member 23 . Third, the stopping member 29 is fixed to the back wall 110 with the first wall 294 perpendicular to the first sidewalls 130 and the second sidewall 296 perpendicular to the second sidewalls 140 . Finally, the limiting member 31 is secured to the bottom of the receiving portion 150 if not integrally manufactured with it. Referring to FIGS. 1 and 3 , to support the device 100 on a flat surface: the supporting member 25 is pulled out from the slot 160 , to be positioned in a desired position and held in place by means of the limiting grooves 2341 . As a result, the supporting member 25 keeps an angle with the back wall 110 , and cooperates with one of the first sidewalls 130 to support the device 100 in a longitudinal or sideways orientation. Referring to FIG. 4 , when the supporting member 25 is lifted further away from the back wall 110 , to slide the rotating member 23 toward the head portion 272 , whereupon the rotating member 23 may overcome the limiting member 31 and be rotated from the first position to the second position. Referring also to FIG. 5 , after the rotating member 23 has been rotated to the second position, the rotating member 23 is pressed against the bottom of the receiving portion 150 and is again limited to the second position by the limiting member 31 , and the supporting member 25 is adjusted to achieve the desired angle with the back wall 110 by being limited in one of the limiting grooves 2341 . As a result, the supporting member 25 cooperates with one of the second sidewalls 140 to support the device 100 in an upright or vertical orientation. When the device 100 is not being used, the rotating member 23 may be rotated to the first position, and the supporting member 25 retracted in the slot 160 . With the assistance of the supporting mechanism 20 , the device 100 may be supported in different orientations. Although the present disclosure has been specifically described on the basis of the exemplary embodiment thereof, the disclosure is not to be construed as being limited thereto. Various changes or modifications may be made to the embodiment without departing from the scope and spirit of the disclosure.
A supporting mechanism for supporting a device includes a rotating member rotatably coupled to the device, and a supporting member rotatably coupled to the rotating member and being foldable on the device. The rotating member is capable of being rotated from a first position to a second position. When the rotating member is rotated to a first position, the unfolded supporting member supports the device in a first orientation; when the rotating member is rotated to a second position, the supporting member supports the device in a second orientation different from the first orientation. A device having the supporting mechanism is also provided.
Provide a concise summary of the essential information conveyed in the given context.
[ "BACKGROUND 1.", "Technical Field The present disclosure relates to devices, and particularly to a device using a supporting mechanism.", "Description of Related Art Hand-held electronic devices, such as PDAs, MP3s, and mobile phones, for example, are widely used.", "However, most of these hand-held electronic devices do not have a supporting mechanism.", "When a hand-held electronic devices are used to watch movies or read e-books, the users need to physically hold the device, which is inconvenient.", "Therefore, there is room for improvement in the art.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a device having a supporting mechanism in accordance with an embodiment.", "FIG. 2 is a partially enlarged view of the portion II of the device of FIG. 1 .", "FIG. 3 is a cross-sectional view of FIG. 1 .", "FIG. 4 is a perspective view showing the device of FIG. 3 after the supporting mechanism has been turned through a quarter of a circle.", "FIG. 5 is a perspective view showing the device of FIG. 1 supported in another orientation.", "DETAILED DESCRIPTION The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements.", "It should be noted that references to “an”", "or “one”", "embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.", "Referring to FIG. 1 , a device 100 in accordance with an embodiment is shown.", "The device 100 includes a main body 10 and a supporting mechanism 20 mounted to the main body 10 .", "The main body 10 may be an electronic device or may be the shell of an electronic device.", "In the embodiment, the main body 10 is the shell of an electronic device 200 (see FIG. 4 ).", "The electronic device 200 may be a mobile-phone, a personal digital assistant (PDA), PSP and other hand-held electronic devices.", "The supporting mechanism 20 operates to support the main body 10 in a number of different orientations such as sideways or vertically.", "The main body 10 is substantially rectangular, and includes a back wall 110 , a front wall 120 , and first sidewalls 130 and second sidewalls 140 .", "The front wall 120 defines a receiving space 122 (see FIG. 3 ) for receiving the electronic device 200 .", "The back wall 110 recesses to form a receiving portion 150 (see FIG. 3 ), and further defines a U-shaped slot 160 communicating with the receiving portion 150 .", "Referring also to FIG. 2 , the supporting mechanism 20 is mounted to the back wall 110 of the main body 10 , and includes a rotating member 23 rotatably coupled to the back wall 110 , a supporting member 25 rotatably coupled to the rotating member 23 , a post 27 and a stopping member 29 .", "The supporting member 25 is substantially U-shaped and matches the U-shaped slot 160 .", "The supporting member 25 is made of metal, and is capable of being elastically deformed.", "The supporting member 25 includes a cylindrical supporting portion 250 and two arms 251 extending from the supporting portion 250 .", "The proximate ends of the arms 251 are cranked away from each other to form two axially-aligned pivoting rods 252 (see FIG. 3 ).", "The two pivoting rods 252 are substantially parallel to the supporting portion 250 .", "The rotating member 23 is substantially U-shaped, and is rotatably received in the receiving portion 150 .", "The rotating member 23 includes a base 232 and two extending portions 234 respectively extending from two opposite ends of the base 232 .", "Referring to FIG. 3 , the middle of the base 232 defines a substantially round recess 2327 .", "The bottom of the recess 2327 further defines a through hole 2323 extending through the base 232 .", "The ends of the extending portions 234 adjacent to the base 232 respectively define a round hole 2342 .", "The two round holes 2342 receive and hold captive the pivoting rods 252 , such that the supporting member 25 is rotatably coupled to the rotating member 23 .", "The internal sides of the extending portions 234 define a plurality of limiting grooves 2341 .", "The limiting grooves 2341 extend in several radial directions.", "When the supporting member 25 is rotated relative to the rotating member 23 , the limiting grooves 2341 operate to position the supporting member 25 in different positions.", "The post 27 is fixed to the bottom of the receiving portion 150 , and includes a head portion 272 and a cylindrical portion 274 (see FIG. 3 ).", "The diameter of the head portion 272 is substantially less than the size of the recess 2327 , but is greater than the size of the through hole 2323 .", "The diameter of the cylindrical portion 274 is almost the same as the size of the through hole 2323 , such that friction is present to hinder the smooth and free rotation of the rotating member 23 .", "The cylindrical portion 274 extends through the recess 2327 and the through hole 2323 and is fixed to the bottom of the receiving portion 150 , whereby the rotating member 23 is rotatably coupled to the back wall 110 .", "The distance between the head portion 272 and the bottom of the receiving portion 150 is greater than the distance between the bottom of the recess 2327 and the bottom of the receiving portion 150 , thus, a clearance 2328 is defined between the head portion 272 and the bottom of the recess 2327 to allow the rotating member 23 to move a certain distance along the cylindrical portion 274 .", "The stopping member 29 is fixed to the back wall 110 , and is arranged adjacent to the receiving portion 150 .", "A portion of the stopping member 29 forms a cutout 292 .", "The cutout 292 includes a first wall 294 perpendicular to the first sidewalls 130 and a second wall 296 perpendicular to the first wall 294 .", "When the rotating member 23 rotates around the post 27 , the first wall 294 stops the rotating member 23 in a first position with the extending portion 234 parallel to the second sidewalls 140 , and the second sidewall 296 stops the rotating member in a second position perpendicular to the first position.", "The supporting mechanism 20 further includes a limiting member 31 (see FIG. 3 ).", "The limiting member 31 is integral with or secured to the bottom of the receiving portion 150 , and is used to provide a barrier to prevent the rotating member 23 from moving when the rotating member 23 is located in one of the first or second positions.", "In assembly, first, the post 27 is inserted through the recess 2327 and the through hole 2323 , and is fixed to the bottom of the receiving portion 150 , thus, the rotating member 23 is rotatably coupled to the main body 20 .", "Second, the pivoting rods 252 are manipulated into the round holes 2342 , such that the supporting member 25 is rotatably coupled to the rotating member 23 .", "Third, the stopping member 29 is fixed to the back wall 110 with the first wall 294 perpendicular to the first sidewalls 130 and the second sidewall 296 perpendicular to the second sidewalls 140 .", "Finally, the limiting member 31 is secured to the bottom of the receiving portion 150 if not integrally manufactured with it.", "Referring to FIGS. 1 and 3 , to support the device 100 on a flat surface: the supporting member 25 is pulled out from the slot 160 , to be positioned in a desired position and held in place by means of the limiting grooves 2341 .", "As a result, the supporting member 25 keeps an angle with the back wall 110 , and cooperates with one of the first sidewalls 130 to support the device 100 in a longitudinal or sideways orientation.", "Referring to FIG. 4 , when the supporting member 25 is lifted further away from the back wall 110 , to slide the rotating member 23 toward the head portion 272 , whereupon the rotating member 23 may overcome the limiting member 31 and be rotated from the first position to the second position.", "Referring also to FIG. 5 , after the rotating member 23 has been rotated to the second position, the rotating member 23 is pressed against the bottom of the receiving portion 150 and is again limited to the second position by the limiting member 31 , and the supporting member 25 is adjusted to achieve the desired angle with the back wall 110 by being limited in one of the limiting grooves 2341 .", "As a result, the supporting member 25 cooperates with one of the second sidewalls 140 to support the device 100 in an upright or vertical orientation.", "When the device 100 is not being used, the rotating member 23 may be rotated to the first position, and the supporting member 25 retracted in the slot 160 .", "With the assistance of the supporting mechanism 20 , the device 100 may be supported in different orientations.", "Although the present disclosure has been specifically described on the basis of the exemplary embodiment thereof, the disclosure is not to be construed as being limited thereto.", "Various changes or modifications may be made to the embodiment without departing from the scope and spirit of the disclosure." ]
This application is a divisional of co-pending application Ser. No. 09/596,556, filed on Jun. 19, 2000, the entire contents of which are hereby incorporated by reference and for which priority is claimed under 35 U.S.C. § 120; and this application claims priority of Application No. 2000 2948 filed in Norway on Jun. 8, 2000 under 35 U.S.C. § 119. This invention relates to the field of holography, in particular to a method and a device for recording optical holograms by means of amorphous molecular semiconductor (AMS) films deposited on a glass substrate. BACKGROUND A particular suited media for recording optical holograms are amorphous molecular semiconductor films. In this invention it is preferred to employ an AMS-film deposited on a glass substrate pre-covered with a conducting sub-layer, where the AMS-film consists of 92 wt % of a copolymer comprising N-epoxypropylcarbazole and 5 wt % buthylglycedil ether, doped with 5 wt % of methyl-9-(4-dodecyl-oxyphenyl-1,3-selenathiol-2-ylidene)-2,5,7-trinitrofluorene-4-carboxylate (MDOSTFC) and 4 wt % of hexadecyl-2,7-dinitro-dicyanomethylenfluorene-4-carboxylate (H-DDFC). The composition and functioning of this and similar AMS-films are thoroughly discussed and explained in the applicant's Norwegian application no. 19995273, and is incorporated herein by reference. Optical holographic interferometry technique is well suited for non-destructive testing of internal defects in blocks and units of machines and devices, welded seams, as well as measuring stresses of an object during the object's work load and residual stresses caused by technological processes of welding, forging, soldering etc. These applications are useful for fields such as offshore oil industry, shipping industry, process industry, air industry, and all types of constructions where strength is vital or fatigue may cause a problem. The principle of optical holographic interferometry can very briefly be described as follows: First a hologram of the investigation area of the object is registered and developed by means of the registering medium. Then the investigation area of the object is subject to a load and slightly deformed. Finally, the investigation area of the object and the registering medium containing the first developed holographic are simultaneously illuminated by the object and reference beam respectively. This results in two simultaneous light waves behind the registering medium, one corresponds to the light wave scattered by the investigation area before loading and the other to the light wave scattered by the investigation area after being exposed to the load. An interferogram of the investigation area is created as a result of the superimposition of these two light waves, and eventual defects in the object are revealed by anomalies in the interference fringe pattern. The principle of the holographic interferometry technique and equipment needed to perform this technique in order to reveal defects and measure internal stresses are given in the applicant's Norwegian applications nos. 19995311 and 19995312. Both applications are incorporated herein by reference. As mentioned, this invention relates to a method and a control device for performing registration of holograms on an AMS-flim. STATE OF THE ART The closest technological solution known to us is the device for registration of optical holograms described in patent SU 1807444 “Device for registration of optical holograms on thermoplastic media”. This device is intended for registration and development of holograms on an AMS-film where the AMS-film is deposited on a glass substrate pre-coated with an electrically conductive sub-layer. The device comprises: an registering medium comprising an AMS-film deposited on a transparent conducting sub-layer which itself is deposited on a glass substrate, an optical scheme for hologram formation, an electromechanical shatter which intercepts the laser beam during charging of the AMS-film surface with corona discharges, a high-voltage unit with a corona electrode, a corona charging time-relay, a hologram expose time-relay determining the time of the electrostatic latent image formation, a development time-relay which determines the time of connection of the key-commutator and development voltage unit to the transparent conducting sub-layer for heating the AMS-film and developing the latent electrostatic image into a geometrical relief on the film surface, a developed hologram image reading time-relay, a developed hologram image erasing time-relay which determines the time of connection of the key-commutator with the development voltage unit to the transparent conducting sub-layer, a development and erasing restriction unit using the preliminary set value of the diffraction efficiency and the photo-sensor installed in the minus first diffraction order, and which disconnects the key-commutator and transparent conducting sub-layer as soon as the diffraction efficiency of the restored hologram image has reached the preliminary set value during the development or erasing process, an electronic time-relay of the AMS-film cooling prior the next cycle of hologram registration and development, a temperature sensor with integrator determining the mean temperature of the AMS-film, a comparator which compares the mean temperature of the AMS-film with the preliminary set temperature and which cuts off an other key commutator as soon as the mean temperature of the AMS-film reaches the preliminary set value. During this period, the AMS-film cooling time-relay cannot activate the corona charging time-relay and the device operation is terminated. The operation of the device is realised in the following manner: By switching on the power of 220 V, the voltage is supplied to all units and time-relays. Then, all time-relays are set in the initial state—logic “zero” at the output, the key-commutator is switched off and other key-commutator is switched on, since the AMS-film has not been heated to the mean temperature at which the comparator switches on. The process of hologram registration initiates by turning on the charging time-relay which switches on the high-voltage unit, which again charges the AMS-film (in this case by a corona discharge generated by the corona electrode). The electromechanical shatter intercepts the laser beam during the charging. After finishing the charging process, the trailing edge of the charging pulse switches on the expose time-relay. While the relay is in “ON” state, the registration of a hologram with a laser and the optical hologram registration scheme occurs. A latent electrostatic image is formed during the hologram registration. The trailing edge of the pulse of the relay switches on the development time-relay, which switches on the key-commutator via the development and erasing restriction unit employing the preliminary set value of the diffraction efficiency and connects the development voltage unit to the transparent conducting sub-layer of the registering medium. In this case, the transparent conducting sub-layer and the AMS-film is heated up, and the latent electrostatic image develops into the geometrical relief of the film surface. The development process is restricted by a pre-set diffraction efficiency, by means of the development and erasing restriction unit using the preliminary set value of the diffraction energy. After that, the developed image is fixed by the AMS-film cooling due to a heat removal to the glass substrate, and it can be read during the time controlled by the image reading time-relay. When the device operation is in cyclic mode, the erasing time-relay is switched on after the termination of operation of the relay and the developed image is erased. The leading edge of the pulse of the relay switches on the key-commutator via the development and erasing restriction unit using the preliminary set value of the diffraction efficiency and connects the development voltage unit to the transparent conducting sub-layer. In this case, the erase restriction is realised by the pre-set value of the diffraction efficiency by means of the development and erasing restriction unit using the preliminary set value of the diffraction efficiency. After termination of the erasing process, the AMS-film cooling occurs due to a heat removal to a glass substrate during the period controlled by the electron cooling time-relay. After termination of operation of the electronic cooling relay, the charging time-relay is switched on again (if the mean temperature of the AMS-film is lower than the pre-set value in the development/erasing comparator), and the cycle of hologram registration/erasing is repeated. The mean temperature of the registering medium progressively increases at its continuous cyclic operation and it may reach a value at which the hologram registration would be impossible and the destruction of the registering medium might occur. In order to prevent this, an electric circuit is incorporated in the device, which terminates its operation as soon as the mean temperature of the AMS-film reaches the preliminary given value. This function in the device is realised in following way: The temperature of the AMS-film is measured with the temperature sensor. A signal from its output proceeds to the integrator having the constant-time of the order of several seconds, that allows to exclude the influence of a pulse heating on the mean temperature value. A signal proportional to the mean temperature proceeds from the integrator output to the comparator where it is compared with that corresponding to a pre-set temperature. Comparator operates in response to the coincidence of the signal magnitudes, and its output signal cuts off the other key-commutator, and disconnects output of the cooling time-relay from the input of charging time-relay. Cyclic operation of the device is terminated. However, despite allowing restriction of the development and erasing processes by the fundamental parameter, namely the diffraction efficiency, and the termination of cyclic operation of the device when the mean temperature of the AMS-film reaches the pre-set value, this device has a number of essential drawbacks: It does not allow the maximum achievable and reproducible band parameters for spatial frequencies of the transmitting characteristics, the optimal spatial frequency of the transmitting characteristics, the resolution, holographic sensitivity, and the “signal-to-noise” ratio in the restored holographic image, which are determined by the heating rate of the AMS-film during the development of the latent electrostatic image. This is due to a missing possibility of setting an optimal initial temperature of the registering medium that would give reproducible optimal heating rate of the AMS-film at the same magnitude of the development voltage pulse. It does not allow to obtain the optimal surface potential at which the local breakdowns of the AMS-film have yet not occurred, as well as the optimal charging current of the corona discharge at which the AMS-film surface is not damaged under ion deposition. Thus, it does not allow to reach the maximum achievable and reproducible values of the signal-to-noise ratio in the restored holographic image, the ratio of reference-object beam intensities at hologram registration, the spatial frequency band of transmitting characteristic, the optimal spatial frequency of transmitting characteristic, and the holographic sensitivity. This is caused by the device's lack of control of the charging current of the corona discharge, and the measurement and restriction of the surface potential of AMS-film during its charging by the corona discharge. It does not reach the maximum achievable band parameters for spatial frequencies of the transmitting characteristics, the optimal spatial frequency of the transmitting characteristics, the holographic sensitivity, and the “signal-to-noise” ratio that are partly being determined by the relaxation rate of the latent electrostatic image prior to and during the development process, since the device does not provide reduction of the dark conductivity. It can not be employed for double-exposure holographic interferometry when the delay time after registration of the first hologram exceeds 1 min, since the device does not provide the formation of a long-lived latent image having large relaxation times. It does not allow preservation of the high “signal-to-noise” ratios, the band of spatial frequencies of the transmitting characteristics, the optimal spatial frequency of the transmitting characteristics, the holographic sensitivity under the repeated registrations, and the development and erasing of holograms that are determined in part by the time and temperature of erasing of the developed image, since the device does not provide the elimination of the surface- and bulk space charges of the AMS-film prior to the erasing of the developed image. The photo-sensor of the unit for erasing restriction by the pre-set value of the diffraction efficiency should be first installed in the zeroth diffraction order and measure light intensity in the reference beam in advance of the hologram development process. Thereafter, it should be installed in the minus first diffraction order, the position of which can be changed at replacement of a holographic object. Thus, the device is not a universal device that is independent on the optical scheme of hologram registration. Besides, the device does not provide termination of the hologram developing process in the case when the diffraction efficiency for some reason cannot reach the pre-set value. The latter circumstance can lead to overheating the AMS-film and its failure. The device does not provide the automatic determination of exposure time and consequently, automatic setting of the operation time for the expose time-relay. Manual determination of the expose time and the adjustment of the expose time-relay reduce the operation efficiency of the device. OBJECT OF INVENTION The main object of the invention is to provide a method and a universal device for registration of optical holograms on AMS-films which overcomes the deficiencies mentioned above, and which permits creation of latent electrostatic images either in form of a modulated surface charge density or a modulated photoelectret state in order to be able to perform the double-exposure holographic interferometry technique. It is also an object of the invention to provide a device for registration of optical holograms that allows setting of an optimal initial temperature of the AMS-film, achieves the maximum surface potential during charging of the AMS-film prior to registration of the holographic image, reduces the dark conductivity of the AMS-film to a minimum, is able to create long lived latent images, eliminates the bulk and surface space charges of the AMS-film prior to erasing the developed image, restricts the development and erasing process by the pre-set value of the diffraction efficiency as measured in the zeroth order of diffraction, provides automatic determination of exposure times, and that is suitable for universal use and which is independent upon the optical scheme employed. SHORT DESCRIPTION OF THE FIGURE FIG. 1 gives a schematic representation of the universal device for recording optical holograms according to the invention. BRIEF DESCRIPTION OF THE INVENTION The objects of the invention can be achieved by the device and method described in the appended claims and in the discussion given below. The objectives of the invention can be achieved by a control device for registering optical holograms on AMS-films which operates in such a way that the AMS-films possess the maximum achievable information parameters, namely by obtaining the greatest possible values for: Holographic sensitivity, optimal spatial frequency of the transmitted characteristic, band parameters for the spatial frequencies of the transmitted characteristic, “signal-to-noise” ratio in the restored holographic image, reference and object beam intensities ratio during hologram registration, and cycling ability. It is also an advantage that the device provides optimal operation efficiency of the registering media based on AMS-films, and restricts the development and erasing of the hologram upon reaching the pre-set value of the diffraction efficiency measured in the zeroth order of diffraction. The latter makes the device a universal device. A preferred way to achieve these ideal operation conditions is to incorporate the following characteristic features into the previously discussed device (see SU 1807444). These features are: Develop the latent electrostatic image into a geometrical relief at the optimal heating rate of the AMS-film, and initiate the heating at an optimal film temperature. Charge the surface of the AMS-film prior to recording of the image at a pre-set and firmly controlled maximum charging current up to the maximum allowable surface potential of the AMS-film. Reduce the electron and hole components of the dark conductivity of the AMS-film. Eliminate the surface- and bulk space charges of the AMS-film prior to the erasing of the developed image. Form a latent photoelectret hologram image that has large relaxation times which allows the use of registering media based on AMS-films in optical schemes of double-exposure holographic interferometry. Measure the diffraction efficiency of holograms in the zeroth diffraction order Restrict the hologram development process not only by the pre-set value of diffraction efficiency, but also by the equality to zero of the first derivative of the dependence of the diffraction efficiency on the development time. The above given features are preferred since they make the device very versatile, so called “universal” and independent of the employed optical scheme of hologram formation. In order to increase the operation efficiency of the device, an automatic determination of exposure time and automatic setting of the operation time for the exposure time-relay may be included. DETAILED DESCRIPTION OF THE INVENTION The invention will now be described in greater detail by reference to the block-diagram presented in FIG. 1 which show a control device for registering optical holograms according to a preferred embodiment of the invention. The control device consists of: A source 1 of coherent light (laser) with an optical scheme 2 of hologram formation, a registering medium 3 – 5 , where 3 is the AMS-film containing 92 wt % of a copolymer comprising N-epoxypropylcarbazole copolymer with 5 wt % buthy1glycedile ether doped with 5 wt % methyl-9-(4-dodecyl-oxyphenyl-1,3-selenathiol-2-ylidene)-2,5,7-trinitrofluorene-4-carboxylate (MDOSTFC) and 4 wt % hexadecyl-2,7-dinitro-dicyanomethylenfluorene-4-carboxylate (HDDFC), an electric circuit 6 – 10 for the setting of the optimal initial temperature of the registering medium, where 6 is a temperature sensor installed immediately on the AMS-film surface 3 , 7 is an initial temperature comparator which sets the initial temperature, compares the measured temperature of registering medium with the preliminary set value, and switches on the initial temperature key-commutator 8 when the above temperatures are coincident, 9 is the initial temperature power source, and indicator 10 displays “Ready” as soon as the measured value of initial temperature reaches the pre-set value, an electric circuit 11 – 18 for the charging of the AMS-film surface by corona discharges and for controlling the corona discharges, where 11 is an electronic charging time-relay which switches on a high voltage source 12 , 13 is a corona electrode, 14 is a surface potential measuring unit with an electrostatic probe 15 , 17 is a surface potential comparator in which the surface potential of charging is pre-set and which terminates operation of the charging time-relay 11 as soon as the measured value of the surface potential reaches the preliminary set value, 16 is a corona discharge current measuring unit which measures the corona current and tunes the high voltage of the unit 12 as soon as measured corona discharge current deviates from the pre-set value, 18 is an electromechanical shatter which intercepts a laser beam during the AMS-film surface charging with corona discharge, an electric circuit 11 – 23 , 41 for the reduction of the hole and electron components of the dark conductivity of the AMS-film, where the functions of elements 11 – 18 has been described above, 19 is a pulse preliminary heating electronic time-relay for the corona charged AMS-film which connects a development-erasing voltage unit 21 to the transparent conducting sub-layer 4 of the registering medium via a switched on development-erasing key-commutator 20 , 41 is a dark electroconductivity comparator which cuts off the pulse preliminary heating time-relay 19 as soon as the AMS-film surface potential reaches 0.8 of the initial maximal allowed value, 22 is an electronic recharging time-relay for the recharging of the AMS-film surface to the pre-set value of the surface potential given by a comparator 23 , an opto-electronic circuit 26 – 24 for determination and adjustment of the exposure time, where a photo-sensor 26 which is measuring the light intensity in the reference beam is installed in the zeroth diffraction order, 25 is an exposition determining unit which terminates operation of an exposure time-relay 24 as soon as its operation time reaches the value determined by the unit 25 , an electric circuit for the formation of a latent photoelectret image which contains the above considered units and elements 11 – 26 . as well as the following novel units and elements K 2 , 27 , 28 , 29 , where K 2 is a button marked “Photoelectret state” which connects the exposure time-relay 24 output to the input of a latent photoelectret image formation time-relay 27 , while this relay switches on the development/erasing key-commutator 20 , and connects it via the development-erasing voltage unit 21 to the transparent conducting sub-layer 4 for the period of latent photoelectret image formation in the AMS-film, this time is restricted by an opto-electric scheme 26 , 32 – 34 , 37 of a latent electrostatic image formation restriction given as a pre-set value of the diffraction efficiency comprising 0.005%, 28 is the switching unit for a flash lamp 29 which turns it on for fixing the latent photoelectret image as soon as the photoelectret image formation time relay 27 terminates the operation, an electric circuit 30 , 20 , 21 for development of the latent electrostatic and photoelectret images, where 30 is a development time-relay which switches on the development/erasing key-commutator 20 and connects it via the development-erasing voltage unit 21 for the time of development of latent electrostatic and photoelectret image, which is restricted by an opto-electronic circuit 26 , 32 – 34 , 35 of the development restriction given by a pre-set value of the diffraction efficiency ranging within 0.5–30%, an electric circuit K 3 , 31 , 20 , 21 for erasing the developed image, where K 3 is a button marked “erasing” which in “ON” state switches on the erasing time-relay, the relay in its turn switches on the development/erasing key-commutator 20 and connects it via the development/erasing voltage unit 21 to the transparent conducting sub-layer 4 during the period of the developed image erasing, which is restricted by an opto-electric circuit 26 , 32 – 34 , 36 for erasing restriction given by a pre-set value of the diffraction efficiency, an opto-electric circuit 26 , 32 – 34 , 35 for development restriction given by the pre-set value of diffraction efficiency, where 26 is the photo-sensor installed in the zeroth diffraction order, 32 is a unit of separation and measurement of the variable component of the reference beam light intensity, 33 is a unit for measuring and memorising the reference beam intensity prior to the latent image development, 34 is a diffraction efficiency calculating unit, 35 is a development comparator where a pre-set value of diffraction efficiency ranging within 0.5–30% is adjusted and where a comparison of measured diffraction efficiency with the pre-set value occurs, the comparator 35 switches off the development/erasing key-commutator 20 when the measured diffraction efficiency coincides with the pre-set value, and thus terminates the development process, an opto-electric circuit 26 , 32 – 34 , 36 for erasing restriction by the pre-set value of diffraction efficiency, where 26 , 32 – 34 are elements and units which are described above and 36 is a comparator which switches off the development/erasing key-commutator 20 as soon as the measured value of diffraction efficiency reaches the pre-set value, an opto-electric circuit 26 , 32 – 34 , 37 for restriction of the latent image transformation into the latent photoelectret image, where 26 , 32 – 34 are elements and units which are described above and 37 is a pulse preheating comparator which participates in formation of the latent photoelectret image and terminates the AMS-film heating as soon as the diffraction efficiency reaches the value of 0.005, an opto-electric circuit 26 , 32 – 34 , 38 , 39 for restriction of the development process by reaching the maximum of the dependence of diffraction efficiency on the development time, where 26 , 32 – 34 are elements and units described above, 38 is a differentiator which calculates the first derivative of the dependence of the diffraction efficiency on the development time, and 39 is a comparator of the differentiator which switches on the development/erasing commutator 20 as soon as the first derivative of the above dependence equals to zero, and a low-voltage supply unit 40 . Operation of the Device In optical schemes of the holographic interferometry, as well as in other schemes of optical holography, the device can operate in two modes: A “real-time scale mode” and a “double exposure mode”. Before activating the device in one of these operation modes, one should switch the device on and perform an initial preparation of the device that includes setting the optimal starting temperature of the registering medium. Besides, the device has a separate final operating mode, “the mode of erasing of the developed image”. The “real-time scale mode” consists of four successive stages. The first stage is charging of the AMS-film surface by a controlled corona discharge. The second stage is reduction of electron and hole components of the dark conductivity of the AMS-film. The third stage is an exposure of the hologram. accompanied with the formation of the latent electrostatic image. The fourth stage is the development of the latent electrostatic image of the hologram up to the level of the preliminary set value of diffraction efficiency. The double exposure mode” includes the first three stages of the “real time scale mode” and two additional stages, namely formation of latent photoelectret image and fixation of the latent photoelectret image. The development of the latent photoelectret image is performed when the device operates in the “real time scale mode” . The “mode of erasing of developed image” is run by the researcher manually and consists of two stages, a stage of reducing the surface—and bulk space charge of the AMS-film, and thereafter erasing the developed image on the hologram. By switching on the device, the device becomes connected to a power supply with voltage 220 V. Then the supply unit of low-voltage circuits 40 switches on and the power is supplied to all units of the device. The laser 1 is switched on, all time-relays are reset into their initial state, logical “zero” is set on output, the starting temperature key-commutator 8 is open, the development/erasing key-commutator 20 is closed, and the electric circuit 6 – 10 for setting the optimal initial temperature of the registering medium begins to work. Setting the optimal starting temperature for the recording medium. The value of the optimal starting temperature should be determined beforehand, during the studies of information properties of the registering medium. For the chosen registering medium, the optimal starting temperature is within 35–40° C. depending on the ratio of the mass part of its components. It is pre-set in the starting temperature comparator 7 . After switching on the device, the starting temperature voltage source 9 is connected to transparent conducting sub-layer 4 of the registering medium via opened starting temperature key-commutator 8 . The electric current goes through the transparent conducting sub-layer 4 , which is being heated up and thereby heats the AMS-film 3 . A temperature sensor 6 continuously measures the temperature of the AMS-film, and the value of temperature is continuously applied to the starting temperature comparator 7 . As soon as the measured value of the temperature reaches the pre-set value in the starting temperature comparator 7 , the latter cuts off the starting temperature key-commutator 8 and heating of the transparent conducting sub-layer terminates. This is accompanied with lighting the indicator “Ready” 10 which signals that the “device” is ready to start operation, because the output voltage of the starting temperature comparator is sufficient for switching on the charging time-relay 11 . The Real Time Scale Mode. Activation of the device in “real time scale mode”. In this operating mode, the button K 2 “Photoelectret state” is in its initial state at which the output of the expose time-relay 24 is connected to the input of the development time-relay 30 . Pressing the button K 1 “Start” activates the device. Thus, the starting temperature comparator 7 switches on the charging time-relay 11 , and the process of charging the AMS-film surface 3 begins. Charging the Surface of the AMS-Film in Controlled Corona Discharge. This process is performed by means of electric circuits 11 – 18 for charging of the AMS-film surface in corona discharge and for corona discharge control. After switching on: The charging time-relay 11 switches on the electromechanical shutter 18 which shuts the laser beam I for the time of the charging process, it switches on the high voltage source 12 , thus high voltage is applied to the corona electrode 13 . A corona discharge is created over the surface of the AMS-film 3 , and positive ions are deposited on its surface. During the charging of the AMS-film surface 3 , the constant maximal allowable pre-set value of the corona discharge current is hold at which the destruction of the AMS-film surface by the bombarding positive ions is not yet observed. This is performed by the corona discharge current measuring unit 16 , which acts as a stabiliser of the voltage dropping on the resistor R 1 . In the case of deviation of the voltage on this resistor from the pre-set value, the corona discharge current measuring unit 16 performs necessary changes of the output voltage of the high voltage source 12 , and thus it holds the constant value of the corona discharge current. The process of charging the AMS-film surface 3 up to pre-set maximum allowed value of the surface potential is performed in the following way: The value of the surface potential should be experimentally determined in advance (during the study of information properties of the registering medium) and loaded into the surface potential comparator 17 . The surface potential is continuously measured by the probe 15 and the surface potential measuring unit 14 during the charging of the AMS-film surface 3 , and the measured value is applied as input to the surface potential comparator 17 , where it is compared with the pre-set value of surface potential. In the case of coincidence of these values, the surface potential comparator 17 interrupts the operation of the time-relay 11 , which then cuts off the high voltage source 12 , and the process of charging the AMS-film surface terminates. Reduction of the electron and hole component of the dark conductivity of the AMS-film is performed by the “electric circuit for reduction of the electron and hole component of the dark conductivity of the AMS-film” 11 – 23 , 41 . Elements and units 11 – 18 are also used in “electric circuit for charging the AMS-film in the corona discharge and for corona discharge control”. The controlled charging of the film surface in corona discharge has been considered in the previous section. This procedure can also be considered as the first step in the process of reducing the electron and hole component of the dark conductivity. The second step, which immediately follows the first one, is the pulse heating of the charged AMS-film 3 . The trailing edge of the pulse of the charging time-relay 11 switches on the pulse preliminary heating time-relay 19 , which in its turn opens the development-erasing key commutator 20 and connects the development-erasing voltage unit to the transparent conducting sub-layer 4 . The latter is heated and heats the AMS-film 3 for a sufficient time for reducing the considered components of the dark conductivity. In the course of continuous reduction of the dark conductivity, a decrease of the surface potential also occurs and the latter value comprises 0.8 of the maximal allowable value by the moment when the dark conductivity has been reduced. This value of the surface potential is used by the device for the time restriction of the pulse preliminary heating of the AMS-film 3 , and it is applied to the dark conductivity comparator 41 . The probe 15 and surface potential measuring unit 14 measure the surface potential during the pulse preheating. As soon as it is equal to 0.8 of its maximal allowable starting value, the comparator 41 cuts off the pulse preliminary heating time-relay 19 and the process of pulse preheating terminates. The trailing edge of the pulse of the pulse preliminary heating time relay 19 opens the recharging time-relay, which in its turn switches on the high voltage source 12 , and the AMS-film surface 3 is recharged to the starting maximal allowable value of the surface potential. The recharging of the AMS-film surface occurs also in a controlled corona discharge where the control of the corona current is performed by the corona discharge current control unit 16 (see the stage “charging of the AMS-film surface in controlled corona discharge”). The restriction of the surface potential, to which the recharging is to be performed, is realised by the recharging comparator 23 . As soon as the surface potential measured with the probe 15 and surface potential measuring unit 14 becomes equal to the maximal allowable value, the recharging comparator 23 cuts off the recharging time-relay 22 and the process of recharging terminates. Exposing the Hologram. The trailing edge of the pulse of the recharging time-relay 22 cuts off the electromechanical shutter 18 and switches on the expose time-relay 24 . Thus, the process of formation of the latent electrostatic image of the hologram in the AMS-film 3 by means of laser 1 , optical scheme for hologram formation 2 , and opto-electric scheme 24 – 26 for determining and setting of the exposure time begins. The determination of exposure time unit 25 employ the predetermined holographic sensitivity and the reference beam intensity measured with the photo-sensor 26 to determine the exposure time and cut off the exposure time-relay 24 . This occurs as soon as the time of its operation, from the moment it is switched on, becomes equal to the time defined by the unit 25 . Developing the Latent Electrostatic Image with the Pre-Set Value of the Diffraction Efficiency. This is performed by means of the electric circuit for development of the latent electrostatic and latent photoelectret image 30 , 20 , 21 , and the opto-electric scheme for development process restriction by the pre-set level of the diffraction efficiency, 26 , 32 – 35 . After finishing the stage of “hologram exposure”, the trailing edge of the pulse of the expose time-relay 24 switches on the development time-relay 30 . The leading edge of the pulse of the development time-relay 30 opens the development/erasing key-commutator 20 and connects it via the development/erasing voltage unit 21 to the transparent conducting sub-layer 4 . Electric current runs through the sub-layer 4 and heats it, resulting in a heating of the AMS-film 3 and a transformation of the latent electrostatic image into a geometrical relief on the surface of the AMS-film. At this stage, the hologram image restores and the diffraction efficiency is continuously determined and entered to the development comparator 35 by means of the photo-sensor 26 , the unit of measurement of the reference beam intensity in the initial moment of the development 33 , unit of separation and measurement of the variable component of the reference beam light intensity 32 during the development, and the diffraction efficiency calculation unit 34 . In comparator 35 , the measured value of diffraction efficiency is compared with the pre-set value. As soon as these values coincide, the comparator 35 interrupts the operation of the development time-relay 30 . The trailing edge of the pulse of the development time-relay 30 cuts off the development/erasing key-commutator 20 and disconnects the development/erasing voltage unit 21 from the transparent conducting sub-layer 4 , and the development process terminates. However, in the case when the value of the diffraction efficiency measured during the development is, for some reason, not able to reach the pre-set value in the comparator 35 , the development time is restricted by means of the opto-electric scheme for the development restriction 26 , 32 – 34 , 38 , 39 on basis of finding the maximum of the dependence of the diffraction efficiency on the development time. The values of the diffraction efficiency as determined by the photo-sensor 26 and units 32 – 34 , are also entered into the differentiator 38 . As soon as the value of the first derivative of the dependence of diffraction efficiency on development time becomes equal to zero, the comparator of differentiator 39 cuts off the development time-relay 30 , and the development process terminates. In practice, the device determines whether the time derivative of the diffraction efficiency has reached zero by checking if the calculated derivative has reached a termination condition. The termination condition can for instance be that the calculated derivative changes sign from a positive numerical value to a negative numerical value, or it may be that the absolute value of the calculated derivative is less than a threshold value which is close to zero. There may of course be other ways to check this condition, the aim is to terminate development process as soon as the diffraction efficiency stops increasing and levels out with time. The Double Exposure Mode. Activation of the device in the double exposure mode. This is performed by pressing the button K 2 , “Photoelectret state”. As soon as this takes place, the output of the expose time-relay 24 is connected to the input of the photoelectret state formation time-relay 27 . The device operation in this mode is supported by the opto-electric scheme for latent photoelectret image formation 11 – 26 , 27 – 29 . This includes the first three stages of the “real time scale mode,” where the reduction of the electron and hole components of the dark conductivity occurs and the latent electrostatic image of hologram is formed. In addition there are two new stages, the formation and fixation of the latent photoelectret image. Formation of the latent photoelectret image. After finishing the third stage of the “real time scale mode”, as a result of which the latent electrostatic image is formed, the trailing edge of the pulse of the expose time-relay 24 switches on the photoelectret state formation time-relay 27 . The photoelectret state formation time-relay 27 opens the development/erasing key-commutator 20 and connects the development/erasing voltage unit 21 to the transparent conducting sub-layer 4 . The latter is heated and as a result, heats up the AMS-film 3 , and the latent electrostatic image is transformed into a latent photoelectret image. The heating time of the AMS-film 3 for transforming the latent electrostatic image into a photoelectret image, is restricted by the opto-electric scheme for restriction of the transformation of the latent electrostatic image into the latent photoelectret image, 26 , 32 – 34 , 37 . This is performed as follows: During the heating of the AMS-film 3 simultaneously with formation of the latent photoelectret image, a partial development of the latent electrostatic image into a visible one takes place. The diffraction efficiency of the restored hologram image is monitored. The measured value of diffraction efficiency is entered to the pulse heating comparator 37 , which switches off the photoelectret state formation time-relay 27 as soon as the measured value of diffraction efficiency becomes equal to 0.005. The development/erasing key-commutator 20 is thus switched off, and the development/erasing voltage unit 21 is disconnected from the transparent conducting sub-layer 4 . Fixing the Latent Photoelectret Image. This is performed immediately after the stage of forming the latent photoelectret image. The trailing edge of the pulse of the photoelectret state formation time-relay 27 switches on the flash lamp switching unit 28 , the flash lamp 29 comes into operation and illuminates the AMS-film surface 3 . This results in shielding and fixation of the latent photoelectret image. The development of the latent photoelectret image occurs at activation of the device operation in the “real time scale mode” which occurs after loading of the holographic object. The obtained latent photoelectret hologram image of the object in its initial state and the obtained latent electrostatic image of the same object, but subjected to loading, will be developed and fixed simultaneously. The Mode of Erasing the Developed Image. This mode is intended for erasing the developed hologram image before reuse of the registering medium for hologram registration. To start the “mode of erasing of developed image,” it is necessary to press the button K 3 “Erasing.” The erasing time-relay 31 is thus switched on and the leading edge of its pulse turns on the developed/erasing key-commutator 20 and connects the development/erasing voltage unit 21 to the transparent conducting sub-layer of registering medium 4 . Simultaneously, the leading edge of the pulse erasing time-relay 31 switches on the flash lamp switching unit 28 . Flash lamp 29 illuminates the AMS-film 3 and the reduction of its surface- and bulk space charges occurs. The time of erasing of the developed image is restricted by the opto-electric scheme 26 , 32 – 34 , 36 for the developed image erasing restriction by the pre-set level of the diffraction efficiency. As soon as the diffraction efficiency reaches a value of 0.01 in the course of erasing of the developed image, the erasure comparator 36 cuts off the erasure time-relay 31 . The trailing edge of pulse of the erasure time-relay 36 therewith switches off the development/erasing key-commutator 20 , and the erasing process terminates. Experimental Verification of the Device. To check the operation of the device, an AMS-film consisting of 92 wt % of a copolymer comprising N-epoxypropylcarbazole with buthylglycedil ether (EPC +5 wt % BGE) doped with 5 wt % methyl-9-(4-dodecyl-oxyphenyl-1,3-selenathiol-2-ylidene)-2,5,7-trinitrofluorene-4-carboxylate (MDOSTFC ) and 3 wt % hexadecyl-2,7-dinitro-dicyanomethylenfluorene-4-carboxylate (H-DDFC). The AMS-film was deposited on a glass substrate with an area of 50*40 mm 2 , and coated with a transparent conducting sub-layer of the tin dioxide with resistance 20 ohm with two silver contacts. The active surface area of the registering medium was 40*40 mm 2 and the thickness of the AMS-film was 1 μm. The maximal allowable values of the surface potential, at which local breakdowns of the AMS-film are not yet observed and the optimal value of the charging current at which the destruction of the film surface does not yet occur, are set before initiating the registration of the holograms. These values were found slightly dependent on the starting temperature of registering medium in the temperature range of 15–40° C., and equal to 125 V/μm and 1 μA/cm 2 , respectively. In addition, the following voltages were determined: The output voltage from the high voltage source 12 which controlled the mentioned conditions of charging, the voltage from the starting temperature voltage source 9 which provides setting and maintenance of the optimal starting temperature in the temperature range 15–40° C., and the voltage from the development/erasing voltage unit 21 which provides the optimal heating rate about 10 6 ° C./sec. These voltages were equal to 15–30 kV, 10 V, and 300 V, respectively. Then the equipment was subject to the following tests: 1. Determination of the optimal starting temperature. For determining the optimal starting temperature, the device operates in the “real time scale mode”, and the holographic sensitivity for various spatial frequencies and a signal-to-noise ratio in the restored hologram image of a “black-and-white” picture are measured. Then: i) charging of the AMS-film surface is performed with an uncontrolled corona discharge at voltage 20 kV, the charging time is set by charging time-relay 11 and it approximately corresponds to the charging time of the AMS-film to the potential of saturation; ii) reducing the electron and hole components of dark conductivity is not performed, and the output of the charging time-relay 11 is connected directly to the input of the expose time relay 24 ; iii) the exposure time is set by the expose time-relay 24 , and the exposition determination unit 25 has been switched off, iv) the diffraction efficiency value equal to 30% is set in the development comparator 35 and development time is mainly restricted by the opto-electric scheme 26 , 32 – 34 , 38 , 39 for restriction of development process on maximum of the diffraction efficiency dependence on development time. As a result of measurements, it was found that the optimal starting temperature is 36° C. Thus, the holographic sensitivity for optimal spatial frequency of 600 mm −1 is 1300 m 2 /J, the resolution is 1100 m 2/ J, and signal-to-noise ratio is 58. In the same time, for starting temperature of registering medium equal to 20° C., the holographic sensitivity is 1100 m 2 /J for optimal spatial frequency of 450 mm −1 , the resolution is 900 mm −1 , and the signal-to-noise ratio is 50. Therefore, including the electric circuit of establishment of optimal starting temperature into the device makes it possible to achieve optimal values of information parameters. Besides, it should be noted that it also makes it possible to obtain reproducible information parameters of the device with accuracy no less than 5%. 2. Determination of the influence of the control procedure of the corona discharge during the AMS-film surface charging on the information properties of the device. The same information parameters were determined in these measurements as when determining the optimal starting temperature value. However, in contrast to the measurements considered in test 1 , the starting temperature of registering medium equal to 36° C. was set in these measurements, and the charging of the AMS-film surface was performed in a controlled corona discharge. The maximal allowable value of surface potential equal to 125 V was pre-set in the surface potential comparator 17 , and the optimal charging current was set in the corona current measuring unit 16 to be 1 μA. As a result of measurements, it was found that the holographic sensitivity is 1200 m 2 /J at optimal spatial frequency 545 mm −1 , resolution is 1000 mm −1 , and signal-to-noise ratio is 125. Therefore, the incorporation of the control of the corona discharge allows one to enhance the signal-to-noise ratio more than twice, although it leads to some decrease of resolution and holographic sensitivity. 3. Determination of the influence of reduction of electron and hole components of the dark conductivity on information properties of the device. In contrast to the measurement procedure considered above in test 1 and 2 , in the course of these measurements the output of the charging time-relay 11 is connected to the input of the pulse preheating time-relay 19 , and the electric circuit of reducing the electron and hole component of the dark conductivity 11 – 18 , 19 – 23 , 41 has been used to full extent in these measurements. As a result of measurements, it was found the following: the holographic sensitivity at optimal spatial frequency 700 mm −1 is 1650 m 2 /J, and resolution is 1700 mm −1 . Additional experiments have shown that the maximal allowable value of the surface potential preserves the AMS-film surface until the moment when the development of the latent electrostatic image into a visible image is started. This value exceeds the corresponding value for the case when no reducing the electron and hole components of dark conductivity was applied by not more than 20%. Such a considerable increase of the optimal spatial frequency of transmitting characteristic and the resolution ability is not only due to the reduction of bulk dark conductivity, but due to reduction of the surface dark conductivity too. As for the increase of the signal-to-noise ratio, this can also be connected with reducing the spontaneous electret state which acts as an additional source of noise. Besides, in the course of these measurements, the greatest possible ratio of light intensities of the reference and object beams under hologram registration is determined. It comprises 10 6 and is more than an order of magnitude larger than that in the case when the dark conductivity reduction has not been applied. Thus, incorporation of the pulse preheating time-relay, the dark conductivity comparator, and the recharging time-relay allows one to enhance the holographic sensitivity and resolution ability of the device, on the average, by a factor of 1.5. 4. Checking the accuracy of the restriction of the latent electrostatic image development. This may be performed by means of the opto-electric scheme for the development restriction 26 , 32 – 35 using the pre-set value of the diffraction efficiency. As it was considered above, the diffraction efficiency is measured with a photo-sensor installed in zero diffraction order, and with units 32 – 34 . The measured diffraction efficiency is entered into the development comparator 35 , where it is compared with the pre-set value of diffraction efficiency. In these measurements, the development process has been terminated at values of diffraction efficiency equal to 0.005; 0.01; 0.1; 1; 5 and 10%, respectively. After terminating the development process at the pre-set value of diffraction efficiency, the diffraction efficiency is measured in each case by usual means, i.e. it is found as the division of the measured light intensities in the minus first diffraction order by the reference beam, As a result of the performed measurements, it was found that the accuracy of termination of the development process by the pre-set value of the diffraction efficiency is within ±0.5% for diffraction efficiencies in the range of 1–10%; ±2.5 for diffraction efficiencies in the range of 0.1%, and ±15% for the diffraction efficiency of 0.005%. Thus, the device restricts the process of hologram development by the pre-set value of diffraction efficiency with high degree of accuracy. The employment of elements and units enabling measuring the diffraction efficiency in zero diffraction order allows one to make this a more efficient device which is universal, that is, independent on the scheme of hologram registration. 5. Checking the device in the “double exposure mode”. This was also checked during the determination of the holographic sensitivity of the device in the photoelectret latent image formation mode, as well as the lifetime of the latent photoelectret image. It is found that the holographic sensitivity of the device in the photoelectret latent image formation mode is, on the average, 30% less than that in the case of the latent electrostatic image formation. The lifetime of the latent photoelectret image, estimated from the delay time prior to the development, comprised 20 h, which is three orders of magnitude greater than the lifetime of the latent electrostatic image. By lifetime we mean the relaxation time, that is the time before the image has weakened to such an extent that it can no longer be employed in the formation of the interferogram. Thus, incorporation of the latent photoelectret image formation time-relay, as well as the flash lamp switching unit and the flash lamp itself into the device makes possible the use of the device for double exposure holographic interferometry. 6. Checking the influence of the reduction of the surface and bulk space charges in the AMS-film before erasing with the flash lamp on the cycling ability. The cycling ability was estimated as the number of cycles of registration, development and erasing of holograms the AMS-film could be exposed for before the holographic sensitivity and signal-to-noise ratio showed a two times reduction. When the flash lamp was used, the cyclic ability being estimated from the reduction of diffraction efficiency and reduction of the signal-to-noise ratio was 4800 rounds compared to 1600 rounds without the lamp. That is, about three times more than in the case without the flash. Thus, the incorporation of the flash lamp switching unit and the flash lamp into the device allowed to enhance the cycling ability of the AMS-films by a factor of three.
This invention relates to the field of holography, in particular to a method and a device for recording optical holograms by means of amorphous molecular semiconductor (AMS) films deposited on a glass substrate pre-covered with a transparent electric conducting sub-layer. More precisely, the invention relates to a method and device for registering optical holograms on AMS-films which operates in such a way that the AMS-films possess the maximum achievable information parameters: Holographic sensitivity, optimal spatial frequency of the transmitted characteristic, band parameters for the spatial frequencies of the transmitted characteristic, “signal-to-noise” ratio in the restored holographic image, reference and object beam intensities ratio during hologram registration, and cycling ability. It is also an advantage that the device provides optimal operation efficiency of the registering media based on AMS-films, and restricts the development and erasing of the hologram upon reaching the pre-set value of the diffraction efficiency measured in the zeroth order of diffraction. The latter makes the device a universal device.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "This application is a divisional of co-pending application Ser.", "No. 09/596,556, filed on Jun. 19, 2000, the entire contents of which are hereby incorporated by reference and for which priority is claimed under 35 U.S.C. § 120;", "and this application claims priority of Application No. 2000 2948 filed in Norway on Jun. 8, 2000 under 35 U.S.C. § 119.", "This invention relates to the field of holography, in particular to a method and a device for recording optical holograms by means of amorphous molecular semiconductor (AMS) films deposited on a glass substrate.", "BACKGROUND A particular suited media for recording optical holograms are amorphous molecular semiconductor films.", "In this invention it is preferred to employ an AMS-film deposited on a glass substrate pre-covered with a conducting sub-layer, where the AMS-film consists of 92 wt % of a copolymer comprising N-epoxypropylcarbazole and 5 wt % buthylglycedil ether, doped with 5 wt % of methyl-9-(4-dodecyl-oxyphenyl-1,3-selenathiol-2-ylidene)-2,5,7-trinitrofluorene-4-carboxylate (MDOSTFC) and 4 wt % of hexadecyl-2,7-dinitro-dicyanomethylenfluorene-4-carboxylate (H-DDFC).", "The composition and functioning of this and similar AMS-films are thoroughly discussed and explained in the applicant's Norwegian application no. 19995273, and is incorporated herein by reference.", "Optical holographic interferometry technique is well suited for non-destructive testing of internal defects in blocks and units of machines and devices, welded seams, as well as measuring stresses of an object during the object's work load and residual stresses caused by technological processes of welding, forging, soldering etc.", "These applications are useful for fields such as offshore oil industry, shipping industry, process industry, air industry, and all types of constructions where strength is vital or fatigue may cause a problem.", "The principle of optical holographic interferometry can very briefly be described as follows: First a hologram of the investigation area of the object is registered and developed by means of the registering medium.", "Then the investigation area of the object is subject to a load and slightly deformed.", "Finally, the investigation area of the object and the registering medium containing the first developed holographic are simultaneously illuminated by the object and reference beam respectively.", "This results in two simultaneous light waves behind the registering medium, one corresponds to the light wave scattered by the investigation area before loading and the other to the light wave scattered by the investigation area after being exposed to the load.", "An interferogram of the investigation area is created as a result of the superimposition of these two light waves, and eventual defects in the object are revealed by anomalies in the interference fringe pattern.", "The principle of the holographic interferometry technique and equipment needed to perform this technique in order to reveal defects and measure internal stresses are given in the applicant's Norwegian applications nos.", "19995311 and 19995312.", "Both applications are incorporated herein by reference.", "As mentioned, this invention relates to a method and a control device for performing registration of holograms on an AMS-flim.", "STATE OF THE ART The closest technological solution known to us is the device for registration of optical holograms described in patent SU 1807444 “Device for registration of optical holograms on thermoplastic media.”", "This device is intended for registration and development of holograms on an AMS-film where the AMS-film is deposited on a glass substrate pre-coated with an electrically conductive sub-layer.", "The device comprises: an registering medium comprising an AMS-film deposited on a transparent conducting sub-layer which itself is deposited on a glass substrate, an optical scheme for hologram formation, an electromechanical shatter which intercepts the laser beam during charging of the AMS-film surface with corona discharges, a high-voltage unit with a corona electrode, a corona charging time-relay, a hologram expose time-relay determining the time of the electrostatic latent image formation, a development time-relay which determines the time of connection of the key-commutator and development voltage unit to the transparent conducting sub-layer for heating the AMS-film and developing the latent electrostatic image into a geometrical relief on the film surface, a developed hologram image reading time-relay, a developed hologram image erasing time-relay which determines the time of connection of the key-commutator with the development voltage unit to the transparent conducting sub-layer, a development and erasing restriction unit using the preliminary set value of the diffraction efficiency and the photo-sensor installed in the minus first diffraction order, and which disconnects the key-commutator and transparent conducting sub-layer as soon as the diffraction efficiency of the restored hologram image has reached the preliminary set value during the development or erasing process, an electronic time-relay of the AMS-film cooling prior the next cycle of hologram registration and development, a temperature sensor with integrator determining the mean temperature of the AMS-film, a comparator which compares the mean temperature of the AMS-film with the preliminary set temperature and which cuts off an other key commutator as soon as the mean temperature of the AMS-film reaches the preliminary set value.", "During this period, the AMS-film cooling time-relay cannot activate the corona charging time-relay and the device operation is terminated.", "The operation of the device is realised in the following manner: By switching on the power of 220 V, the voltage is supplied to all units and time-relays.", "Then, all time-relays are set in the initial state—logic “zero”", "at the output, the key-commutator is switched off and other key-commutator is switched on, since the AMS-film has not been heated to the mean temperature at which the comparator switches on.", "The process of hologram registration initiates by turning on the charging time-relay which switches on the high-voltage unit, which again charges the AMS-film (in this case by a corona discharge generated by the corona electrode).", "The electromechanical shatter intercepts the laser beam during the charging.", "After finishing the charging process, the trailing edge of the charging pulse switches on the expose time-relay.", "While the relay is in “ON”", "state, the registration of a hologram with a laser and the optical hologram registration scheme occurs.", "A latent electrostatic image is formed during the hologram registration.", "The trailing edge of the pulse of the relay switches on the development time-relay, which switches on the key-commutator via the development and erasing restriction unit employing the preliminary set value of the diffraction efficiency and connects the development voltage unit to the transparent conducting sub-layer of the registering medium.", "In this case, the transparent conducting sub-layer and the AMS-film is heated up, and the latent electrostatic image develops into the geometrical relief of the film surface.", "The development process is restricted by a pre-set diffraction efficiency, by means of the development and erasing restriction unit using the preliminary set value of the diffraction energy.", "After that, the developed image is fixed by the AMS-film cooling due to a heat removal to the glass substrate, and it can be read during the time controlled by the image reading time-relay.", "When the device operation is in cyclic mode, the erasing time-relay is switched on after the termination of operation of the relay and the developed image is erased.", "The leading edge of the pulse of the relay switches on the key-commutator via the development and erasing restriction unit using the preliminary set value of the diffraction efficiency and connects the development voltage unit to the transparent conducting sub-layer.", "In this case, the erase restriction is realised by the pre-set value of the diffraction efficiency by means of the development and erasing restriction unit using the preliminary set value of the diffraction efficiency.", "After termination of the erasing process, the AMS-film cooling occurs due to a heat removal to a glass substrate during the period controlled by the electron cooling time-relay.", "After termination of operation of the electronic cooling relay, the charging time-relay is switched on again (if the mean temperature of the AMS-film is lower than the pre-set value in the development/erasing comparator), and the cycle of hologram registration/erasing is repeated.", "The mean temperature of the registering medium progressively increases at its continuous cyclic operation and it may reach a value at which the hologram registration would be impossible and the destruction of the registering medium might occur.", "In order to prevent this, an electric circuit is incorporated in the device, which terminates its operation as soon as the mean temperature of the AMS-film reaches the preliminary given value.", "This function in the device is realised in following way: The temperature of the AMS-film is measured with the temperature sensor.", "A signal from its output proceeds to the integrator having the constant-time of the order of several seconds, that allows to exclude the influence of a pulse heating on the mean temperature value.", "A signal proportional to the mean temperature proceeds from the integrator output to the comparator where it is compared with that corresponding to a pre-set temperature.", "Comparator operates in response to the coincidence of the signal magnitudes, and its output signal cuts off the other key-commutator, and disconnects output of the cooling time-relay from the input of charging time-relay.", "Cyclic operation of the device is terminated.", "However, despite allowing restriction of the development and erasing processes by the fundamental parameter, namely the diffraction efficiency, and the termination of cyclic operation of the device when the mean temperature of the AMS-film reaches the pre-set value, this device has a number of essential drawbacks: It does not allow the maximum achievable and reproducible band parameters for spatial frequencies of the transmitting characteristics, the optimal spatial frequency of the transmitting characteristics, the resolution, holographic sensitivity, and the “signal-to-noise”", "ratio in the restored holographic image, which are determined by the heating rate of the AMS-film during the development of the latent electrostatic image.", "This is due to a missing possibility of setting an optimal initial temperature of the registering medium that would give reproducible optimal heating rate of the AMS-film at the same magnitude of the development voltage pulse.", "It does not allow to obtain the optimal surface potential at which the local breakdowns of the AMS-film have yet not occurred, as well as the optimal charging current of the corona discharge at which the AMS-film surface is not damaged under ion deposition.", "Thus, it does not allow to reach the maximum achievable and reproducible values of the signal-to-noise ratio in the restored holographic image, the ratio of reference-object beam intensities at hologram registration, the spatial frequency band of transmitting characteristic, the optimal spatial frequency of transmitting characteristic, and the holographic sensitivity.", "This is caused by the device's lack of control of the charging current of the corona discharge, and the measurement and restriction of the surface potential of AMS-film during its charging by the corona discharge.", "It does not reach the maximum achievable band parameters for spatial frequencies of the transmitting characteristics, the optimal spatial frequency of the transmitting characteristics, the holographic sensitivity, and the “signal-to-noise”", "ratio that are partly being determined by the relaxation rate of the latent electrostatic image prior to and during the development process, since the device does not provide reduction of the dark conductivity.", "It can not be employed for double-exposure holographic interferometry when the delay time after registration of the first hologram exceeds 1 min, since the device does not provide the formation of a long-lived latent image having large relaxation times.", "It does not allow preservation of the high “signal-to-noise”", "ratios, the band of spatial frequencies of the transmitting characteristics, the optimal spatial frequency of the transmitting characteristics, the holographic sensitivity under the repeated registrations, and the development and erasing of holograms that are determined in part by the time and temperature of erasing of the developed image, since the device does not provide the elimination of the surface- and bulk space charges of the AMS-film prior to the erasing of the developed image.", "The photo-sensor of the unit for erasing restriction by the pre-set value of the diffraction efficiency should be first installed in the zeroth diffraction order and measure light intensity in the reference beam in advance of the hologram development process.", "Thereafter, it should be installed in the minus first diffraction order, the position of which can be changed at replacement of a holographic object.", "Thus, the device is not a universal device that is independent on the optical scheme of hologram registration.", "Besides, the device does not provide termination of the hologram developing process in the case when the diffraction efficiency for some reason cannot reach the pre-set value.", "The latter circumstance can lead to overheating the AMS-film and its failure.", "The device does not provide the automatic determination of exposure time and consequently, automatic setting of the operation time for the expose time-relay.", "Manual determination of the expose time and the adjustment of the expose time-relay reduce the operation efficiency of the device.", "OBJECT OF INVENTION The main object of the invention is to provide a method and a universal device for registration of optical holograms on AMS-films which overcomes the deficiencies mentioned above, and which permits creation of latent electrostatic images either in form of a modulated surface charge density or a modulated photoelectret state in order to be able to perform the double-exposure holographic interferometry technique.", "It is also an object of the invention to provide a device for registration of optical holograms that allows setting of an optimal initial temperature of the AMS-film, achieves the maximum surface potential during charging of the AMS-film prior to registration of the holographic image, reduces the dark conductivity of the AMS-film to a minimum, is able to create long lived latent images, eliminates the bulk and surface space charges of the AMS-film prior to erasing the developed image, restricts the development and erasing process by the pre-set value of the diffraction efficiency as measured in the zeroth order of diffraction, provides automatic determination of exposure times, and that is suitable for universal use and which is independent upon the optical scheme employed.", "SHORT DESCRIPTION OF THE FIGURE FIG. 1 gives a schematic representation of the universal device for recording optical holograms according to the invention.", "BRIEF DESCRIPTION OF THE INVENTION The objects of the invention can be achieved by the device and method described in the appended claims and in the discussion given below.", "The objectives of the invention can be achieved by a control device for registering optical holograms on AMS-films which operates in such a way that the AMS-films possess the maximum achievable information parameters, namely by obtaining the greatest possible values for: Holographic sensitivity, optimal spatial frequency of the transmitted characteristic, band parameters for the spatial frequencies of the transmitted characteristic, “signal-to-noise”", "ratio in the restored holographic image, reference and object beam intensities ratio during hologram registration, and cycling ability.", "It is also an advantage that the device provides optimal operation efficiency of the registering media based on AMS-films, and restricts the development and erasing of the hologram upon reaching the pre-set value of the diffraction efficiency measured in the zeroth order of diffraction.", "The latter makes the device a universal device.", "A preferred way to achieve these ideal operation conditions is to incorporate the following characteristic features into the previously discussed device (see SU 1807444).", "These features are: Develop the latent electrostatic image into a geometrical relief at the optimal heating rate of the AMS-film, and initiate the heating at an optimal film temperature.", "Charge the surface of the AMS-film prior to recording of the image at a pre-set and firmly controlled maximum charging current up to the maximum allowable surface potential of the AMS-film.", "Reduce the electron and hole components of the dark conductivity of the AMS-film.", "Eliminate the surface- and bulk space charges of the AMS-film prior to the erasing of the developed image.", "Form a latent photoelectret hologram image that has large relaxation times which allows the use of registering media based on AMS-films in optical schemes of double-exposure holographic interferometry.", "Measure the diffraction efficiency of holograms in the zeroth diffraction order Restrict the hologram development process not only by the pre-set value of diffraction efficiency, but also by the equality to zero of the first derivative of the dependence of the diffraction efficiency on the development time.", "The above given features are preferred since they make the device very versatile, so called “universal”", "and independent of the employed optical scheme of hologram formation.", "In order to increase the operation efficiency of the device, an automatic determination of exposure time and automatic setting of the operation time for the exposure time-relay may be included.", "DETAILED DESCRIPTION OF THE INVENTION The invention will now be described in greater detail by reference to the block-diagram presented in FIG. 1 which show a control device for registering optical holograms according to a preferred embodiment of the invention.", "The control device consists of: A source 1 of coherent light (laser) with an optical scheme 2 of hologram formation, a registering medium 3 – 5 , where 3 is the AMS-film containing 92 wt % of a copolymer comprising N-epoxypropylcarbazole copolymer with 5 wt % buthy1glycedile ether doped with 5 wt % methyl-9-(4-dodecyl-oxyphenyl-1,3-selenathiol-2-ylidene)-2,5,7-trinitrofluorene-4-carboxylate (MDOSTFC) and 4 wt % hexadecyl-2,7-dinitro-dicyanomethylenfluorene-4-carboxylate (HDDFC), an electric circuit 6 – 10 for the setting of the optimal initial temperature of the registering medium, where 6 is a temperature sensor installed immediately on the AMS-film surface 3 , 7 is an initial temperature comparator which sets the initial temperature, compares the measured temperature of registering medium with the preliminary set value, and switches on the initial temperature key-commutator 8 when the above temperatures are coincident, 9 is the initial temperature power source, and indicator 10 displays “Ready”", "as soon as the measured value of initial temperature reaches the pre-set value, an electric circuit 11 – 18 for the charging of the AMS-film surface by corona discharges and for controlling the corona discharges, where 11 is an electronic charging time-relay which switches on a high voltage source 12 , 13 is a corona electrode, 14 is a surface potential measuring unit with an electrostatic probe 15 , 17 is a surface potential comparator in which the surface potential of charging is pre-set and which terminates operation of the charging time-relay 11 as soon as the measured value of the surface potential reaches the preliminary set value, 16 is a corona discharge current measuring unit which measures the corona current and tunes the high voltage of the unit 12 as soon as measured corona discharge current deviates from the pre-set value, 18 is an electromechanical shatter which intercepts a laser beam during the AMS-film surface charging with corona discharge, an electric circuit 11 – 23 , 41 for the reduction of the hole and electron components of the dark conductivity of the AMS-film, where the functions of elements 11 – 18 has been described above, 19 is a pulse preliminary heating electronic time-relay for the corona charged AMS-film which connects a development-erasing voltage unit 21 to the transparent conducting sub-layer 4 of the registering medium via a switched on development-erasing key-commutator 20 , 41 is a dark electroconductivity comparator which cuts off the pulse preliminary heating time-relay 19 as soon as the AMS-film surface potential reaches 0.8 of the initial maximal allowed value, 22 is an electronic recharging time-relay for the recharging of the AMS-film surface to the pre-set value of the surface potential given by a comparator 23 , an opto-electronic circuit 26 – 24 for determination and adjustment of the exposure time, where a photo-sensor 26 which is measuring the light intensity in the reference beam is installed in the zeroth diffraction order, 25 is an exposition determining unit which terminates operation of an exposure time-relay 24 as soon as its operation time reaches the value determined by the unit 25 , an electric circuit for the formation of a latent photoelectret image which contains the above considered units and elements 11 – 26 .", "as well as the following novel units and elements K 2 , 27 , 28 , 29 , where K 2 is a button marked “Photoelectret state”", "which connects the exposure time-relay 24 output to the input of a latent photoelectret image formation time-relay 27 , while this relay switches on the development/erasing key-commutator 20 , and connects it via the development-erasing voltage unit 21 to the transparent conducting sub-layer 4 for the period of latent photoelectret image formation in the AMS-film, this time is restricted by an opto-electric scheme 26 , 32 – 34 , 37 of a latent electrostatic image formation restriction given as a pre-set value of the diffraction efficiency comprising 0.005%, 28 is the switching unit for a flash lamp 29 which turns it on for fixing the latent photoelectret image as soon as the photoelectret image formation time relay 27 terminates the operation, an electric circuit 30 , 20 , 21 for development of the latent electrostatic and photoelectret images, where 30 is a development time-relay which switches on the development/erasing key-commutator 20 and connects it via the development-erasing voltage unit 21 for the time of development of latent electrostatic and photoelectret image, which is restricted by an opto-electronic circuit 26 , 32 – 34 , 35 of the development restriction given by a pre-set value of the diffraction efficiency ranging within 0.5–30%, an electric circuit K 3 , 31 , 20 , 21 for erasing the developed image, where K 3 is a button marked “erasing”", "which in “ON”", "state switches on the erasing time-relay, the relay in its turn switches on the development/erasing key-commutator 20 and connects it via the development/erasing voltage unit 21 to the transparent conducting sub-layer 4 during the period of the developed image erasing, which is restricted by an opto-electric circuit 26 , 32 – 34 , 36 for erasing restriction given by a pre-set value of the diffraction efficiency, an opto-electric circuit 26 , 32 – 34 , 35 for development restriction given by the pre-set value of diffraction efficiency, where 26 is the photo-sensor installed in the zeroth diffraction order, 32 is a unit of separation and measurement of the variable component of the reference beam light intensity, 33 is a unit for measuring and memorising the reference beam intensity prior to the latent image development, 34 is a diffraction efficiency calculating unit, 35 is a development comparator where a pre-set value of diffraction efficiency ranging within 0.5–30% is adjusted and where a comparison of measured diffraction efficiency with the pre-set value occurs, the comparator 35 switches off the development/erasing key-commutator 20 when the measured diffraction efficiency coincides with the pre-set value, and thus terminates the development process, an opto-electric circuit 26 , 32 – 34 , 36 for erasing restriction by the pre-set value of diffraction efficiency, where 26 , 32 – 34 are elements and units which are described above and 36 is a comparator which switches off the development/erasing key-commutator 20 as soon as the measured value of diffraction efficiency reaches the pre-set value, an opto-electric circuit 26 , 32 – 34 , 37 for restriction of the latent image transformation into the latent photoelectret image, where 26 , 32 – 34 are elements and units which are described above and 37 is a pulse preheating comparator which participates in formation of the latent photoelectret image and terminates the AMS-film heating as soon as the diffraction efficiency reaches the value of 0.005, an opto-electric circuit 26 , 32 – 34 , 38 , 39 for restriction of the development process by reaching the maximum of the dependence of diffraction efficiency on the development time, where 26 , 32 – 34 are elements and units described above, 38 is a differentiator which calculates the first derivative of the dependence of the diffraction efficiency on the development time, and 39 is a comparator of the differentiator which switches on the development/erasing commutator 20 as soon as the first derivative of the above dependence equals to zero, and a low-voltage supply unit 40 .", "Operation of the Device In optical schemes of the holographic interferometry, as well as in other schemes of optical holography, the device can operate in two modes: A “real-time scale mode”", "and a “double exposure mode.”", "Before activating the device in one of these operation modes, one should switch the device on and perform an initial preparation of the device that includes setting the optimal starting temperature of the registering medium.", "Besides, the device has a separate final operating mode, “the mode of erasing of the developed image.”", "The “real-time scale mode”", "consists of four successive stages.", "The first stage is charging of the AMS-film surface by a controlled corona discharge.", "The second stage is reduction of electron and hole components of the dark conductivity of the AMS-film.", "The third stage is an exposure of the hologram.", "accompanied with the formation of the latent electrostatic image.", "The fourth stage is the development of the latent electrostatic image of the hologram up to the level of the preliminary set value of diffraction efficiency.", "The double exposure mode”", "includes the first three stages of the “real time scale mode”", "and two additional stages, namely formation of latent photoelectret image and fixation of the latent photoelectret image.", "The development of the latent photoelectret image is performed when the device operates in the “real time scale mode”", "The “mode of erasing of developed image”", "is run by the researcher manually and consists of two stages, a stage of reducing the surface—and bulk space charge of the AMS-film, and thereafter erasing the developed image on the hologram.", "By switching on the device, the device becomes connected to a power supply with voltage 220 V. Then the supply unit of low-voltage circuits 40 switches on and the power is supplied to all units of the device.", "The laser 1 is switched on, all time-relays are reset into their initial state, logical “zero”", "is set on output, the starting temperature key-commutator 8 is open, the development/erasing key-commutator 20 is closed, and the electric circuit 6 – 10 for setting the optimal initial temperature of the registering medium begins to work.", "Setting the optimal starting temperature for the recording medium.", "The value of the optimal starting temperature should be determined beforehand, during the studies of information properties of the registering medium.", "For the chosen registering medium, the optimal starting temperature is within 35–40° C. depending on the ratio of the mass part of its components.", "It is pre-set in the starting temperature comparator 7 .", "After switching on the device, the starting temperature voltage source 9 is connected to transparent conducting sub-layer 4 of the registering medium via opened starting temperature key-commutator 8 .", "The electric current goes through the transparent conducting sub-layer 4 , which is being heated up and thereby heats the AMS-film 3 .", "A temperature sensor 6 continuously measures the temperature of the AMS-film, and the value of temperature is continuously applied to the starting temperature comparator 7 .", "As soon as the measured value of the temperature reaches the pre-set value in the starting temperature comparator 7 , the latter cuts off the starting temperature key-commutator 8 and heating of the transparent conducting sub-layer terminates.", "This is accompanied with lighting the indicator “Ready”", "10 which signals that the “device”", "is ready to start operation, because the output voltage of the starting temperature comparator is sufficient for switching on the charging time-relay 11 .", "The Real Time Scale Mode.", "Activation of the device in “real time scale mode.”", "In this operating mode, the button K 2 “Photoelectret state”", "is in its initial state at which the output of the expose time-relay 24 is connected to the input of the development time-relay 30 .", "Pressing the button K 1 “Start”", "activates the device.", "Thus, the starting temperature comparator 7 switches on the charging time-relay 11 , and the process of charging the AMS-film surface 3 begins.", "Charging the Surface of the AMS-Film in Controlled Corona Discharge.", "This process is performed by means of electric circuits 11 – 18 for charging of the AMS-film surface in corona discharge and for corona discharge control.", "After switching on: The charging time-relay 11 switches on the electromechanical shutter 18 which shuts the laser beam I for the time of the charging process, it switches on the high voltage source 12 , thus high voltage is applied to the corona electrode 13 .", "A corona discharge is created over the surface of the AMS-film 3 , and positive ions are deposited on its surface.", "During the charging of the AMS-film surface 3 , the constant maximal allowable pre-set value of the corona discharge current is hold at which the destruction of the AMS-film surface by the bombarding positive ions is not yet observed.", "This is performed by the corona discharge current measuring unit 16 , which acts as a stabiliser of the voltage dropping on the resistor R 1 .", "In the case of deviation of the voltage on this resistor from the pre-set value, the corona discharge current measuring unit 16 performs necessary changes of the output voltage of the high voltage source 12 , and thus it holds the constant value of the corona discharge current.", "The process of charging the AMS-film surface 3 up to pre-set maximum allowed value of the surface potential is performed in the following way: The value of the surface potential should be experimentally determined in advance (during the study of information properties of the registering medium) and loaded into the surface potential comparator 17 .", "The surface potential is continuously measured by the probe 15 and the surface potential measuring unit 14 during the charging of the AMS-film surface 3 , and the measured value is applied as input to the surface potential comparator 17 , where it is compared with the pre-set value of surface potential.", "In the case of coincidence of these values, the surface potential comparator 17 interrupts the operation of the time-relay 11 , which then cuts off the high voltage source 12 , and the process of charging the AMS-film surface terminates.", "Reduction of the electron and hole component of the dark conductivity of the AMS-film is performed by the “electric circuit for reduction of the electron and hole component of the dark conductivity of the AMS-film”", "11 – 23 , 41 .", "Elements and units 11 – 18 are also used in “electric circuit for charging the AMS-film in the corona discharge and for corona discharge control.”", "The controlled charging of the film surface in corona discharge has been considered in the previous section.", "This procedure can also be considered as the first step in the process of reducing the electron and hole component of the dark conductivity.", "The second step, which immediately follows the first one, is the pulse heating of the charged AMS-film 3 .", "The trailing edge of the pulse of the charging time-relay 11 switches on the pulse preliminary heating time-relay 19 , which in its turn opens the development-erasing key commutator 20 and connects the development-erasing voltage unit to the transparent conducting sub-layer 4 .", "The latter is heated and heats the AMS-film 3 for a sufficient time for reducing the considered components of the dark conductivity.", "In the course of continuous reduction of the dark conductivity, a decrease of the surface potential also occurs and the latter value comprises 0.8 of the maximal allowable value by the moment when the dark conductivity has been reduced.", "This value of the surface potential is used by the device for the time restriction of the pulse preliminary heating of the AMS-film 3 , and it is applied to the dark conductivity comparator 41 .", "The probe 15 and surface potential measuring unit 14 measure the surface potential during the pulse preheating.", "As soon as it is equal to 0.8 of its maximal allowable starting value, the comparator 41 cuts off the pulse preliminary heating time-relay 19 and the process of pulse preheating terminates.", "The trailing edge of the pulse of the pulse preliminary heating time relay 19 opens the recharging time-relay, which in its turn switches on the high voltage source 12 , and the AMS-film surface 3 is recharged to the starting maximal allowable value of the surface potential.", "The recharging of the AMS-film surface occurs also in a controlled corona discharge where the control of the corona current is performed by the corona discharge current control unit 16 (see the stage “charging of the AMS-film surface in controlled corona discharge”).", "The restriction of the surface potential, to which the recharging is to be performed, is realised by the recharging comparator 23 .", "As soon as the surface potential measured with the probe 15 and surface potential measuring unit 14 becomes equal to the maximal allowable value, the recharging comparator 23 cuts off the recharging time-relay 22 and the process of recharging terminates.", "Exposing the Hologram.", "The trailing edge of the pulse of the recharging time-relay 22 cuts off the electromechanical shutter 18 and switches on the expose time-relay 24 .", "Thus, the process of formation of the latent electrostatic image of the hologram in the AMS-film 3 by means of laser 1 , optical scheme for hologram formation 2 , and opto-electric scheme 24 – 26 for determining and setting of the exposure time begins.", "The determination of exposure time unit 25 employ the predetermined holographic sensitivity and the reference beam intensity measured with the photo-sensor 26 to determine the exposure time and cut off the exposure time-relay 24 .", "This occurs as soon as the time of its operation, from the moment it is switched on, becomes equal to the time defined by the unit 25 .", "Developing the Latent Electrostatic Image with the Pre-Set Value of the Diffraction Efficiency.", "This is performed by means of the electric circuit for development of the latent electrostatic and latent photoelectret image 30 , 20 , 21 , and the opto-electric scheme for development process restriction by the pre-set level of the diffraction efficiency, 26 , 32 – 35 .", "After finishing the stage of “hologram exposure”, the trailing edge of the pulse of the expose time-relay 24 switches on the development time-relay 30 .", "The leading edge of the pulse of the development time-relay 30 opens the development/erasing key-commutator 20 and connects it via the development/erasing voltage unit 21 to the transparent conducting sub-layer 4 .", "Electric current runs through the sub-layer 4 and heats it, resulting in a heating of the AMS-film 3 and a transformation of the latent electrostatic image into a geometrical relief on the surface of the AMS-film.", "At this stage, the hologram image restores and the diffraction efficiency is continuously determined and entered to the development comparator 35 by means of the photo-sensor 26 , the unit of measurement of the reference beam intensity in the initial moment of the development 33 , unit of separation and measurement of the variable component of the reference beam light intensity 32 during the development, and the diffraction efficiency calculation unit 34 .", "In comparator 35 , the measured value of diffraction efficiency is compared with the pre-set value.", "As soon as these values coincide, the comparator 35 interrupts the operation of the development time-relay 30 .", "The trailing edge of the pulse of the development time-relay 30 cuts off the development/erasing key-commutator 20 and disconnects the development/erasing voltage unit 21 from the transparent conducting sub-layer 4 , and the development process terminates.", "However, in the case when the value of the diffraction efficiency measured during the development is, for some reason, not able to reach the pre-set value in the comparator 35 , the development time is restricted by means of the opto-electric scheme for the development restriction 26 , 32 – 34 , 38 , 39 on basis of finding the maximum of the dependence of the diffraction efficiency on the development time.", "The values of the diffraction efficiency as determined by the photo-sensor 26 and units 32 – 34 , are also entered into the differentiator 38 .", "As soon as the value of the first derivative of the dependence of diffraction efficiency on development time becomes equal to zero, the comparator of differentiator 39 cuts off the development time-relay 30 , and the development process terminates.", "In practice, the device determines whether the time derivative of the diffraction efficiency has reached zero by checking if the calculated derivative has reached a termination condition.", "The termination condition can for instance be that the calculated derivative changes sign from a positive numerical value to a negative numerical value, or it may be that the absolute value of the calculated derivative is less than a threshold value which is close to zero.", "There may of course be other ways to check this condition, the aim is to terminate development process as soon as the diffraction efficiency stops increasing and levels out with time.", "The Double Exposure Mode.", "Activation of the device in the double exposure mode.", "This is performed by pressing the button K 2 , “Photoelectret state.”", "As soon as this takes place, the output of the expose time-relay 24 is connected to the input of the photoelectret state formation time-relay 27 .", "The device operation in this mode is supported by the opto-electric scheme for latent photoelectret image formation 11 – 26 , 27 – 29 .", "This includes the first three stages of the “real time scale mode,” where the reduction of the electron and hole components of the dark conductivity occurs and the latent electrostatic image of hologram is formed.", "In addition there are two new stages, the formation and fixation of the latent photoelectret image.", "Formation of the latent photoelectret image.", "After finishing the third stage of the “real time scale mode”, as a result of which the latent electrostatic image is formed, the trailing edge of the pulse of the expose time-relay 24 switches on the photoelectret state formation time-relay 27 .", "The photoelectret state formation time-relay 27 opens the development/erasing key-commutator 20 and connects the development/erasing voltage unit 21 to the transparent conducting sub-layer 4 .", "The latter is heated and as a result, heats up the AMS-film 3 , and the latent electrostatic image is transformed into a latent photoelectret image.", "The heating time of the AMS-film 3 for transforming the latent electrostatic image into a photoelectret image, is restricted by the opto-electric scheme for restriction of the transformation of the latent electrostatic image into the latent photoelectret image, 26 , 32 – 34 , 37 .", "This is performed as follows: During the heating of the AMS-film 3 simultaneously with formation of the latent photoelectret image, a partial development of the latent electrostatic image into a visible one takes place.", "The diffraction efficiency of the restored hologram image is monitored.", "The measured value of diffraction efficiency is entered to the pulse heating comparator 37 , which switches off the photoelectret state formation time-relay 27 as soon as the measured value of diffraction efficiency becomes equal to 0.005.", "The development/erasing key-commutator 20 is thus switched off, and the development/erasing voltage unit 21 is disconnected from the transparent conducting sub-layer 4 .", "Fixing the Latent Photoelectret Image.", "This is performed immediately after the stage of forming the latent photoelectret image.", "The trailing edge of the pulse of the photoelectret state formation time-relay 27 switches on the flash lamp switching unit 28 , the flash lamp 29 comes into operation and illuminates the AMS-film surface 3 .", "This results in shielding and fixation of the latent photoelectret image.", "The development of the latent photoelectret image occurs at activation of the device operation in the “real time scale mode”", "which occurs after loading of the holographic object.", "The obtained latent photoelectret hologram image of the object in its initial state and the obtained latent electrostatic image of the same object, but subjected to loading, will be developed and fixed simultaneously.", "The Mode of Erasing the Developed Image.", "This mode is intended for erasing the developed hologram image before reuse of the registering medium for hologram registration.", "To start the “mode of erasing of developed image,” it is necessary to press the button K 3 “Erasing.”", "The erasing time-relay 31 is thus switched on and the leading edge of its pulse turns on the developed/erasing key-commutator 20 and connects the development/erasing voltage unit 21 to the transparent conducting sub-layer of registering medium 4 .", "Simultaneously, the leading edge of the pulse erasing time-relay 31 switches on the flash lamp switching unit 28 .", "Flash lamp 29 illuminates the AMS-film 3 and the reduction of its surface- and bulk space charges occurs.", "The time of erasing of the developed image is restricted by the opto-electric scheme 26 , 32 – 34 , 36 for the developed image erasing restriction by the pre-set level of the diffraction efficiency.", "As soon as the diffraction efficiency reaches a value of 0.01 in the course of erasing of the developed image, the erasure comparator 36 cuts off the erasure time-relay 31 .", "The trailing edge of pulse of the erasure time-relay 36 therewith switches off the development/erasing key-commutator 20 , and the erasing process terminates.", "Experimental Verification of the Device.", "To check the operation of the device, an AMS-film consisting of 92 wt % of a copolymer comprising N-epoxypropylcarbazole with buthylglycedil ether (EPC +5 wt % BGE) doped with 5 wt % methyl-9-(4-dodecyl-oxyphenyl-1,3-selenathiol-2-ylidene)-2,5,7-trinitrofluorene-4-carboxylate (MDOSTFC ) and 3 wt % hexadecyl-2,7-dinitro-dicyanomethylenfluorene-4-carboxylate (H-DDFC).", "The AMS-film was deposited on a glass substrate with an area of 50*40 mm 2 , and coated with a transparent conducting sub-layer of the tin dioxide with resistance 20 ohm with two silver contacts.", "The active surface area of the registering medium was 40*40 mm 2 and the thickness of the AMS-film was 1 μm.", "The maximal allowable values of the surface potential, at which local breakdowns of the AMS-film are not yet observed and the optimal value of the charging current at which the destruction of the film surface does not yet occur, are set before initiating the registration of the holograms.", "These values were found slightly dependent on the starting temperature of registering medium in the temperature range of 15–40° C., and equal to 125 V/μm and 1 μA/cm 2 , respectively.", "In addition, the following voltages were determined: The output voltage from the high voltage source 12 which controlled the mentioned conditions of charging, the voltage from the starting temperature voltage source 9 which provides setting and maintenance of the optimal starting temperature in the temperature range 15–40° C., and the voltage from the development/erasing voltage unit 21 which provides the optimal heating rate about 10 6 ° C./sec.", "These voltages were equal to 15–30 kV, 10 V, and 300 V, respectively.", "Then the equipment was subject to the following tests: 1.", "Determination of the optimal starting temperature.", "For determining the optimal starting temperature, the device operates in the “real time scale mode”, and the holographic sensitivity for various spatial frequencies and a signal-to-noise ratio in the restored hologram image of a “black-and-white”", "picture are measured.", "Then: i) charging of the AMS-film surface is performed with an uncontrolled corona discharge at voltage 20 kV, the charging time is set by charging time-relay 11 and it approximately corresponds to the charging time of the AMS-film to the potential of saturation;", "ii) reducing the electron and hole components of dark conductivity is not performed, and the output of the charging time-relay 11 is connected directly to the input of the expose time relay 24 ;", "iii) the exposure time is set by the expose time-relay 24 , and the exposition determination unit 25 has been switched off, iv) the diffraction efficiency value equal to 30% is set in the development comparator 35 and development time is mainly restricted by the opto-electric scheme 26 , 32 – 34 , 38 , 39 for restriction of development process on maximum of the diffraction efficiency dependence on development time.", "As a result of measurements, it was found that the optimal starting temperature is 36° C. Thus, the holographic sensitivity for optimal spatial frequency of 600 mm −1 is 1300 m 2 /J, the resolution is 1100 m 2/ J, and signal-to-noise ratio is 58.", "In the same time, for starting temperature of registering medium equal to 20° C., the holographic sensitivity is 1100 m 2 /J for optimal spatial frequency of 450 mm −1 , the resolution is 900 mm −1 , and the signal-to-noise ratio is 50.", "Therefore, including the electric circuit of establishment of optimal starting temperature into the device makes it possible to achieve optimal values of information parameters.", "Besides, it should be noted that it also makes it possible to obtain reproducible information parameters of the device with accuracy no less than 5%.", "Determination of the influence of the control procedure of the corona discharge during the AMS-film surface charging on the information properties of the device.", "The same information parameters were determined in these measurements as when determining the optimal starting temperature value.", "However, in contrast to the measurements considered in test 1 , the starting temperature of registering medium equal to 36° C. was set in these measurements, and the charging of the AMS-film surface was performed in a controlled corona discharge.", "The maximal allowable value of surface potential equal to 125 V was pre-set in the surface potential comparator 17 , and the optimal charging current was set in the corona current measuring unit 16 to be 1 μA.", "As a result of measurements, it was found that the holographic sensitivity is 1200 m 2 /J at optimal spatial frequency 545 mm −1 , resolution is 1000 mm −1 , and signal-to-noise ratio is 125.", "Therefore, the incorporation of the control of the corona discharge allows one to enhance the signal-to-noise ratio more than twice, although it leads to some decrease of resolution and holographic sensitivity.", "Determination of the influence of reduction of electron and hole components of the dark conductivity on information properties of the device.", "In contrast to the measurement procedure considered above in test 1 and 2 , in the course of these measurements the output of the charging time-relay 11 is connected to the input of the pulse preheating time-relay 19 , and the electric circuit of reducing the electron and hole component of the dark conductivity 11 – 18 , 19 – 23 , 41 has been used to full extent in these measurements.", "As a result of measurements, it was found the following: the holographic sensitivity at optimal spatial frequency 700 mm −1 is 1650 m 2 /J, and resolution is 1700 mm −1 .", "Additional experiments have shown that the maximal allowable value of the surface potential preserves the AMS-film surface until the moment when the development of the latent electrostatic image into a visible image is started.", "This value exceeds the corresponding value for the case when no reducing the electron and hole components of dark conductivity was applied by not more than 20%.", "Such a considerable increase of the optimal spatial frequency of transmitting characteristic and the resolution ability is not only due to the reduction of bulk dark conductivity, but due to reduction of the surface dark conductivity too.", "As for the increase of the signal-to-noise ratio, this can also be connected with reducing the spontaneous electret state which acts as an additional source of noise.", "Besides, in the course of these measurements, the greatest possible ratio of light intensities of the reference and object beams under hologram registration is determined.", "It comprises 10 6 and is more than an order of magnitude larger than that in the case when the dark conductivity reduction has not been applied.", "Thus, incorporation of the pulse preheating time-relay, the dark conductivity comparator, and the recharging time-relay allows one to enhance the holographic sensitivity and resolution ability of the device, on the average, by a factor of 1.5.", "Checking the accuracy of the restriction of the latent electrostatic image development.", "This may be performed by means of the opto-electric scheme for the development restriction 26 , 32 – 35 using the pre-set value of the diffraction efficiency.", "As it was considered above, the diffraction efficiency is measured with a photo-sensor installed in zero diffraction order, and with units 32 – 34 .", "The measured diffraction efficiency is entered into the development comparator 35 , where it is compared with the pre-set value of diffraction efficiency.", "In these measurements, the development process has been terminated at values of diffraction efficiency equal to 0.005;", "0.01;", "0.1;", "5 and 10%, respectively.", "After terminating the development process at the pre-set value of diffraction efficiency, the diffraction efficiency is measured in each case by usual means, i.e. it is found as the division of the measured light intensities in the minus first diffraction order by the reference beam, As a result of the performed measurements, it was found that the accuracy of termination of the development process by the pre-set value of the diffraction efficiency is within ±0.5% for diffraction efficiencies in the range of 1–10%;", "±2.5 for diffraction efficiencies in the range of 0.1%, and ±15% for the diffraction efficiency of 0.005%.", "Thus, the device restricts the process of hologram development by the pre-set value of diffraction efficiency with high degree of accuracy.", "The employment of elements and units enabling measuring the diffraction efficiency in zero diffraction order allows one to make this a more efficient device which is universal, that is, independent on the scheme of hologram registration.", "Checking the device in the “double exposure mode.”", "This was also checked during the determination of the holographic sensitivity of the device in the photoelectret latent image formation mode, as well as the lifetime of the latent photoelectret image.", "It is found that the holographic sensitivity of the device in the photoelectret latent image formation mode is, on the average, 30% less than that in the case of the latent electrostatic image formation.", "The lifetime of the latent photoelectret image, estimated from the delay time prior to the development, comprised 20 h, which is three orders of magnitude greater than the lifetime of the latent electrostatic image.", "By lifetime we mean the relaxation time, that is the time before the image has weakened to such an extent that it can no longer be employed in the formation of the interferogram.", "Thus, incorporation of the latent photoelectret image formation time-relay, as well as the flash lamp switching unit and the flash lamp itself into the device makes possible the use of the device for double exposure holographic interferometry.", "Checking the influence of the reduction of the surface and bulk space charges in the AMS-film before erasing with the flash lamp on the cycling ability.", "The cycling ability was estimated as the number of cycles of registration, development and erasing of holograms the AMS-film could be exposed for before the holographic sensitivity and signal-to-noise ratio showed a two times reduction.", "When the flash lamp was used, the cyclic ability being estimated from the reduction of diffraction efficiency and reduction of the signal-to-noise ratio was 4800 rounds compared to 1600 rounds without the lamp.", "That is, about three times more than in the case without the flash.", "Thus, the incorporation of the flash lamp switching unit and the flash lamp into the device allowed to enhance the cycling ability of the AMS-films by a factor of three." ]
FIELD OF THE INVENTION The present invention relates to a process for interconnecting microprocessors connected to a series data bus, in which a master microprocessor transmits characters one by one over the bus for the attention of at least one slave microprocessor associated with a register adapted for receiving a character. The present invention therefore relates to a process for interconnecting microprocessors one of which is a master microprocessor and the others slave microprocessors, the master microprocessor being able to be any one of the microprocessors at any given moment. BACKGROUND OF THE INVENTION The interconnection of microprocessors is a problem which occurs more especially in the use of teleprinters, which comprise several microprocessors. More particularly, the problem posed here is that of interconnecting a master microprocessor and slave microprocessors all connected to a bus over which information must flow from one to the other in series form and at a relatively slow rate. Heretofore, such interconnection has been made in the following way. Each information or character transmitted by a master microprocessor for the attention of a slave microprocessor generally comprises an address and the text of the information properly speaking. Since each micorprocessor is associated with a deserialization and serialization register also connected to the bus, when a master transmits a character, all the registers of the slaves receive this character. Since each microprocessor is also associated with a recognition interface, which is connected thereto as well as to its deserialization register, the interface, if it recognizes its address in the character received by the associated deserialization register, causes the character to be removed from the register and stored in a buffer register, i.e. a memory, shared between the interface and the microprocessor. If not, the character is rejected from the deserialization register. If such has been the procedure up to now, it was so that the reception of a character in a slave microprocessor did not cause interruption of its processing then in progress intended to cause it to provide a proper function, such for example as the control of a printer, so that this slave recognized and so accepted and stored this character in its memory. In fact, to accept a character and store it requires in real time a relatively long period, of the order of 100 μs, and a microprocessor does not always have the time required at the moment when the character reaches it, precisley if processing is in progress which cannot be interrupted. With this process therefore, because of the recognition interface, no additional constraint was suffered in real time and the slave microprocessors were thus relieved of the reception of data. However, the interfaces for recognizing or accepting characters are expensive. According to another solution, a master microprocessor could be adapted so as to transmit again a character, after receiving one, only after a given period of time, sufficient for a slave microprocessor to be able to finish the processing it has in progress before storing the character. This solution is however not very practical, for the predetermined time in question must be longer than the longest of the processing times which may not be interrupted for the whole of the slave microprocessors. SUMMARY OF THE INVENTION The present invention aims then at eliminating these recognition interfaces. For this, the present invention provides a process for interconnecting microprocesors connected to a series data bus, in which a master microprocessor transmits characters one by one over the bus for the attention of at least one slave microprocessor associated with a register adapted for receiving a character, which process is characterized by the fact that a character received in the register of the slave microprocessor is only recognized and removed from the register at the end of the processing which is taking place there at the time of reception of the character, that it is the slave microprocessor which recognizes it and removes it from the register, that the bus remains empty until the character is recognized and removed from the register and that, after recognizing and removing the character from the register, the slave microprocessor transmits an echo signal or character over the bus allowing the master microprocessor to again transmit a character. With the process of the invention, which thus eliminates any need for recognition interfaces, the slave microprocessor or microprocessors may continue their processing in progress after reception of a character in their register. Furthermore, it is no longer after a predetermined time that the master microprocessor transmits a new character but only as soon as it is invited to do so by the reception of the echo transmitted by the slave concerned by the character considered. All the microprocessors are thus synchronized, in that the master microprocessor cannot again transmit a character as long as it does not receive the echo of the preceding one. iI will be noted here that this echo is advantageously the same character as the incident character. The invention is remarkable in that, although it aims at eliminating the recognition interfaces of the known process which, themselves, aimed at preventing the microprocessors from having to themselves recognize the incident characters so as to be able to continue their processing in progress, it proceeds nevertheless by recognition of the characters by the microprocessors. But although it is the microprocessors which recognize the incident characters, they only do so after finishing the processing in progress. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood from the following description of the preferred embodiment of the invention with reference to the accompanying drawings in which: FIG. 1 shows schematically a master microprocessor and a slave microprocessor connected in accordance with the invention; and FIG. 2 shows schematically the asynchronous receiver-transmitter of the microprocessors and its connection elements to the series bus. DETAILED DESCRIPTION OF THE INVENTION The following description concerns the process for interconnecting a master microprocessor and a slave microprocessor. But it will of course be readily understood that the invention applies to the interconnection of an unlimited number of microprocessors, any one of which may at any moment be the master microprocessor. The result is that all the microprocessors have at least all the equipment which will also be described, whether they are in connection with only the described master microprocessor or in connection with only the slave microprocessor. Let us suppose then a first microprocessor 1, master at the time considered and a second microprocessor 2, slave at this same time. They are interconnected by a series bus 3, to which they are connected. Each of the microprocessors comprises an asynchronous receiver-transmitter 4, the deserialization register discussed above, connected to bus 3. Register 4 is of course used also as serialization register for, conversely, transforming into series form a character in parallel form. The microprocessors further comprise a memory 5, an echo recognition device 6, an interrupt mechanism 7, an address register 8, an enabling mechanism 9, all these elements being connected to an internal data bus 10. Register 4 is connected to memory 5 and to the echo recognition device 6 by bus 10, but for ease of understanding these functional connections have been shown in FIG. 1. Similarly, the interrupt mechanism 7 is connected to register 4, to the address register 8 and to the enabling mechanism 9 by bus 10, but these connections have also been shown in FIG. 1. The interrupt mechanism 7 is in reality a part of the sequencer of the microprocessors providing the function of an AND gate. As for the enabling mechanism it is a flip-flop. Let us now turn to the interconnection process. When register 4 of the master microprocessor 1 transmits in series form over bus 3 a character taken from its memory 5, this character is received in register 4 of the slave microprocessor 2 as well as moreover, in all the registers 4 of all the other slave microprocessors (not shown). Let us suppose that it is indeed microprocessor 2 for which this character is intended and that processing is taking place there at the time of reception of this character. When the interruption mechanism 7 is initialized, any processing in progress is interrupted for processing the character received in register 4. The initialization for enabling signal is received on line 11 connecting mechanism 7 to mechanism 9 and it is combined, at the input of mechanism 7, with the "register 4 full" signal, received over line 12 connecting mechanism 7 to register 4. Since it is functionally an AND gate, mechanism 7, when the two signals are present at its inputs 11 and 12, empties register 8 of the address then present for substituting a new one which will cause reading of register 4 and reception of the character contained therein in memory 5, through bus 10. According to the invention, the enabling signal is transmitted at the end of the processing in progress at the time of reception of the character. Until that time, the character received in register 4 was masked by interrupt mechanism 7 Then, the above described procedure takes place and register 4 unloads an echo character for transmission purposes in series form over bus 3 and for reception in parallel form in register 4 of the master microprocessor 1, before being recognized in the recognition device 6. Between reception in register 4 of the slave microprocessor 2 of the character transmitted by the master microprocessor 1 and recognition by device 6 of the master microprocessor 1 of the echo transmitted by the slave microprocessor 2, bus 3 remained empty. In order to avoid, although this is not imperative, the echo provided by register 4 from being taken for an incident character, i.e., so that the incident characters and the echoes are discriminated, this register has special features. The asynchronous transmitter-receiver 4 comprises a receiver part 4' and a transmitter part 4", connected to the series bus 3 by an OR gate 13 and a line interface 14, respectively. The output of gate 13 is connected to input 16 of receiver 4', with one of its inputs being connected to bus 3 and its other input being connected to the input of interface 14 by an inverter 15. The input of interface 14 is also connected to the output 17 of transmitter 4". Let us suppose that, when there is no echo transmitted, the output 17 of transmitter 4" remains at level 1. In this case, the level of the input 16 of receiver 4' must be the same as that of bus 3. When there is transmission of the echo loaded into transmitter 3", the level of bus 3 must be the same as that of the output of the transmitter 4" and the input 16 of receiver 4', which must receive nothing, must remain at level 1. That results, for the input 16 of receiver 4', in the following truth table of: ______________________________________ BusTransmitter 0 1______________________________________0 11 0 1______________________________________ This is why the OR gate 13 and the inverter 15 have been provided.
In a process for interconnecting microprocessors, a master microprocessor (1) transmits a character. All the slave microprocessors receive it in a register (4). If processing is in progress in the slave (2) for which it is intended, the character is masked until the processing is finished. After the processing, the slave microprocessor (2) recognizes it, removes it from the register (4) and loads this latter with an echo intended for the master microprocessor (1), allowing it to transmit a new character.
Identify and summarize the most critical technical features from the given patent document.
[ "FIELD OF THE INVENTION The present invention relates to a process for interconnecting microprocessors connected to a series data bus, in which a master microprocessor transmits characters one by one over the bus for the attention of at least one slave microprocessor associated with a register adapted for receiving a character.", "The present invention therefore relates to a process for interconnecting microprocessors one of which is a master microprocessor and the others slave microprocessors, the master microprocessor being able to be any one of the microprocessors at any given moment.", "BACKGROUND OF THE INVENTION The interconnection of microprocessors is a problem which occurs more especially in the use of teleprinters, which comprise several microprocessors.", "More particularly, the problem posed here is that of interconnecting a master microprocessor and slave microprocessors all connected to a bus over which information must flow from one to the other in series form and at a relatively slow rate.", "Heretofore, such interconnection has been made in the following way.", "Each information or character transmitted by a master microprocessor for the attention of a slave microprocessor generally comprises an address and the text of the information properly speaking.", "Since each micorprocessor is associated with a deserialization and serialization register also connected to the bus, when a master transmits a character, all the registers of the slaves receive this character.", "Since each microprocessor is also associated with a recognition interface, which is connected thereto as well as to its deserialization register, the interface, if it recognizes its address in the character received by the associated deserialization register, causes the character to be removed from the register and stored in a buffer register, i.e. a memory, shared between the interface and the microprocessor.", "If not, the character is rejected from the deserialization register.", "If such has been the procedure up to now, it was so that the reception of a character in a slave microprocessor did not cause interruption of its processing then in progress intended to cause it to provide a proper function, such for example as the control of a printer, so that this slave recognized and so accepted and stored this character in its memory.", "In fact, to accept a character and store it requires in real time a relatively long period, of the order of 100 μs, and a microprocessor does not always have the time required at the moment when the character reaches it, precisley if processing is in progress which cannot be interrupted.", "With this process therefore, because of the recognition interface, no additional constraint was suffered in real time and the slave microprocessors were thus relieved of the reception of data.", "However, the interfaces for recognizing or accepting characters are expensive.", "According to another solution, a master microprocessor could be adapted so as to transmit again a character, after receiving one, only after a given period of time, sufficient for a slave microprocessor to be able to finish the processing it has in progress before storing the character.", "This solution is however not very practical, for the predetermined time in question must be longer than the longest of the processing times which may not be interrupted for the whole of the slave microprocessors.", "SUMMARY OF THE INVENTION The present invention aims then at eliminating these recognition interfaces.", "For this, the present invention provides a process for interconnecting microprocesors connected to a series data bus, in which a master microprocessor transmits characters one by one over the bus for the attention of at least one slave microprocessor associated with a register adapted for receiving a character, which process is characterized by the fact that a character received in the register of the slave microprocessor is only recognized and removed from the register at the end of the processing which is taking place there at the time of reception of the character, that it is the slave microprocessor which recognizes it and removes it from the register, that the bus remains empty until the character is recognized and removed from the register and that, after recognizing and removing the character from the register, the slave microprocessor transmits an echo signal or character over the bus allowing the master microprocessor to again transmit a character.", "With the process of the invention, which thus eliminates any need for recognition interfaces, the slave microprocessor or microprocessors may continue their processing in progress after reception of a character in their register.", "Furthermore, it is no longer after a predetermined time that the master microprocessor transmits a new character but only as soon as it is invited to do so by the reception of the echo transmitted by the slave concerned by the character considered.", "All the microprocessors are thus synchronized, in that the master microprocessor cannot again transmit a character as long as it does not receive the echo of the preceding one.", "iI will be noted here that this echo is advantageously the same character as the incident character.", "The invention is remarkable in that, although it aims at eliminating the recognition interfaces of the known process which, themselves, aimed at preventing the microprocessors from having to themselves recognize the incident characters so as to be able to continue their processing in progress, it proceeds nevertheless by recognition of the characters by the microprocessors.", "But although it is the microprocessors which recognize the incident characters, they only do so after finishing the processing in progress.", "BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood from the following description of the preferred embodiment of the invention with reference to the accompanying drawings in which: FIG. 1 shows schematically a master microprocessor and a slave microprocessor connected in accordance with the invention;", "and FIG. 2 shows schematically the asynchronous receiver-transmitter of the microprocessors and its connection elements to the series bus.", "DETAILED DESCRIPTION OF THE INVENTION The following description concerns the process for interconnecting a master microprocessor and a slave microprocessor.", "But it will of course be readily understood that the invention applies to the interconnection of an unlimited number of microprocessors, any one of which may at any moment be the master microprocessor.", "The result is that all the microprocessors have at least all the equipment which will also be described, whether they are in connection with only the described master microprocessor or in connection with only the slave microprocessor.", "Let us suppose then a first microprocessor 1, master at the time considered and a second microprocessor 2, slave at this same time.", "They are interconnected by a series bus 3, to which they are connected.", "Each of the microprocessors comprises an asynchronous receiver-transmitter 4, the deserialization register discussed above, connected to bus 3.", "Register 4 is of course used also as serialization register for, conversely, transforming into series form a character in parallel form.", "The microprocessors further comprise a memory 5, an echo recognition device 6, an interrupt mechanism 7, an address register 8, an enabling mechanism 9, all these elements being connected to an internal data bus 10.", "Register 4 is connected to memory 5 and to the echo recognition device 6 by bus 10, but for ease of understanding these functional connections have been shown in FIG. 1. Similarly, the interrupt mechanism 7 is connected to register 4, to the address register 8 and to the enabling mechanism 9 by bus 10, but these connections have also been shown in FIG. 1. The interrupt mechanism 7 is in reality a part of the sequencer of the microprocessors providing the function of an AND gate.", "As for the enabling mechanism it is a flip-flop.", "Let us now turn to the interconnection process.", "When register 4 of the master microprocessor 1 transmits in series form over bus 3 a character taken from its memory 5, this character is received in register 4 of the slave microprocessor 2 as well as moreover, in all the registers 4 of all the other slave microprocessors (not shown).", "Let us suppose that it is indeed microprocessor 2 for which this character is intended and that processing is taking place there at the time of reception of this character.", "When the interruption mechanism 7 is initialized, any processing in progress is interrupted for processing the character received in register 4.", "The initialization for enabling signal is received on line 11 connecting mechanism 7 to mechanism 9 and it is combined, at the input of mechanism 7, with the "register 4 full"", "signal, received over line 12 connecting mechanism 7 to register 4.", "Since it is functionally an AND gate, mechanism 7, when the two signals are present at its inputs 11 and 12, empties register 8 of the address then present for substituting a new one which will cause reading of register 4 and reception of the character contained therein in memory 5, through bus 10.", "According to the invention, the enabling signal is transmitted at the end of the processing in progress at the time of reception of the character.", "Until that time, the character received in register 4 was masked by interrupt mechanism 7 Then, the above described procedure takes place and register 4 unloads an echo character for transmission purposes in series form over bus 3 and for reception in parallel form in register 4 of the master microprocessor 1, before being recognized in the recognition device 6.", "Between reception in register 4 of the slave microprocessor 2 of the character transmitted by the master microprocessor 1 and recognition by device 6 of the master microprocessor 1 of the echo transmitted by the slave microprocessor 2, bus 3 remained empty.", "In order to avoid, although this is not imperative, the echo provided by register 4 from being taken for an incident character, i.e., so that the incident characters and the echoes are discriminated, this register has special features.", "The asynchronous transmitter-receiver 4 comprises a receiver part 4'", "and a transmitter part 4", connected to the series bus 3 by an OR gate 13 and a line interface 14, respectively.", "The output of gate 13 is connected to input 16 of receiver 4', with one of its inputs being connected to bus 3 and its other input being connected to the input of interface 14 by an inverter 15.", "The input of interface 14 is also connected to the output 17 of transmitter 4".", "Let us suppose that, when there is no echo transmitted, the output 17 of transmitter 4"", "remains at level 1.", "In this case, the level of the input 16 of receiver 4'", "must be the same as that of bus 3.", "When there is transmission of the echo loaded into transmitter 3", the level of bus 3 must be the same as that of the output of the transmitter 4"", "and the input 16 of receiver 4', which must receive nothing, must remain at level 1.", "That results, for the input 16 of receiver 4', in the following truth table of: ______________________________________ BusTransmitter 0 1______________________________________0 11 0 1______________________________________ This is why the OR gate 13 and the inverter 15 have been provided." ]
BACKGROUND OF THE INVENTION The present invention is directed to sequential fractionation of the contents of a centrifuge tube after the centrifugation operation and, more particularly, is directed to a fractionation system that can remove very small fraction volumes accurately and reproducibly without undesirable mixing of the fractions or losses of the fractions in a transfer tube or line. The system operates without requiring a motor, pump or electrical power. After the centrifugation process, it is necessary to remove fractions of the separated contents in the fluid which has been subjected to centrifugation in order to proceed with the proper analysis of each separated constituent or level of fluid density. When using very small centrifuge tubes, the removal of precise small volumes or fractions of the fluid material from the centrifuge tube without losses or remixing presents a significant problem. Many types of devices have been developed for fractionating the contents of centrifuge tubes. One such approach utilized in a fractionation system is tube slicing whereby the tube is sequentially cut into segments in a special holder and knife assembly so that the fluid can be removed with a pipette from each segment after it is cut. Although tube slicing has been used with some success in separating the contents in extremely small test tubes into only two fractions, the system of tube slicing is entirely impractical and unsuccessful for small tube sequential fractionation process. Another process utilized for tube fractionation is puncturing whereby the tube is pierced with a hollow needle and the contents within the tube are collected slowly drop by drop as a result of applying a slight pressure to a space at the top of the tube. Another method for tube fractionation is the concept of displacement with the tube contents being displaced upward through a special cap assembly by injecting a heavy density fluid into the bottom of the tube by the use of a puncturing needle or by the use of a long capillary placed down into the centrifuge tube. A final primary method used in tube fractionation is aspiration whereby the tube contents are removed in sequential elements from the top of the tube. This is typically done by a syringe either hand held or in a special holder. Also a special assembly using a vacuum pump to withdraw fractions of the tube contents through a capillary placed into the open top of the tube enables fractionation by the aspiration principle. Typically, the methods presently used for tube fractionation provide a somewhat satisfactory approach when using larger centrifuge tubes of 5 milliliters or greater capacity, since losses of the fluid due to leaks or retention in the tubing connections can be tolerated. However, with respect to very small centrifuge tubes such as one holding as small as 0.175 milliliters of fluid, these methods of tube sequential fractionation do not provide satisfactory results. The volumes of fluid being handled in such small centrifuge tubes are so minute that losses due to leaks or retention in the tubing or as a result of remixing cannot be tolerated. SUMMARY OF THE INVENTION The present invention is directed to a sequential fractionation system utilizing a syringe-like apparatus whereby a chamber housing is connected to a frame in such a manner that the housing can be moved very precise distances relative to a plunger or piston within the chamber of the housing. Attached to the chamber housing are removable syringe tips that are used to collect the precise volume of fluid material for each sequential fractionation step. The present invention utilizes no motors or pumps eliminating the need for electrical power. Further, there is no need for connection tubing which would result in possible loss of the fluid volume remaining residually in the tubing. The principal unique feature of the present invention is the manner in which the syringe-like apparatus is used to withdraw aliquots of the fluid contained in the centrifuge tube. The syringe barrel incorporated into the chamber housing is moved downward relative to the syringe piston, which is restrained from moving downward by contact with the top plate of the fractionator. This is in contrast to the usual operation of syringes in which the piston is withdrawn from the barrel held in a fixed position. This novel mode of operation permits fluid aliquots to be removed from the centrifuge tube in a particularly advantageous manner as explained below. No fluid can be drawn into the syringe tip until it contacts the surface of the fluid in the tube. The start of the collection event cannot be initiated until contact is established by the syringe tip on the fluid surface. As the syringe tip and barrel are lowered, fluid is continuously withdrawn into the syringe tip only from the very surface of the contents within the tube which is a completely different operation from the prior art use of a syringe where the tip is immersed within the fluid and the fraction is withdrawn from below the surface rather than on the surface. The present method is essential to obtain sharp separation of fractions and to avoid mixing with fluid further down in the tube. To achieve the above described action of the present invention the volume swept out by the movement of the syringe barrel relative to the piston must be equal to or greater than the volume of the fraction to be collected. This requirement is best met by making the diameter of the syringe barrel slightly larger than the inside diameter of the centrifuge tube. If desired, the syringe diameter can be considerably larger than the tube diameter, but some air may be drawn into the syringe tip with the fluid volume. However, this will not adversely affect the accuracy of the volume of the fraction. The volume of the fraction collected is determined and controlled by measuring the distance which the chamber housing containing the syringe barrel is moved relative to its piston. This measurement is made conveniently by use of an attached measuring device which can accurately measure the movement of the chamber housing. The relationship between the distance moved and the actual volume collected can be calculated from a knowledge of the inside diameter of the centrifuge tube, but it is more accurate and convenient to determine the relationship by weighing fractions collected by movement of the chamber housing a particular distance in a preliminary fractionation using a centrifuge tube filled with water. When the desired volume of the fraction has been drawn into the syringe tip, the chamber housing containing the syringe barrel is now raised. Since the syringe piston is not restrained by contact with the top plate, the piston will move upward with the chamber housing. Thus, the fluid in the springe tip will remain in place undisturbed. The second unique feature of this invention is the fact that each fraction is contained entirely within the syringe tip and there is absolutely no loss due to leaks or retention of fluid in tubing connections. By removal of the tip, the fraction can be quantitatively transferred for subsequent use or analysis. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view of the fractionation apparatus; FIG. 2 is a partial sectional side elevational view of the apparatus; FIG. 3 is a top partial sectional view of the fractionation apparatus; and FIG. 4 is a sectional view taken along the lines 4--4 in FIG. 2. DETAILED DESCRIPTION OF THE INVENTION The fractionator device 10 of the present invention is shown in FIG. 1 having a base 12 on which is secured a frame member 14. At least three support pads or feet 15 are positioned in a balanced relationship on the bottom surface 34 of the base 12. As shown more clearly in FIG. 4, the frame member is an enlarged U-shaped one-piece member having a back portion 16 with integrally formed side panels 18 and 20 that extend perpendicular from the back portion 16. Located on the inside surface 22 of the side panels 18 and 20 and adjacent their free edges 24 are travel grooves 26. As shown in FIG. 1, a top plate 30 is secured over the frame member 14. The travel grooves 26 are designed to receive a travel plate 28 that operates in a manner which will be discussed below. Securely mounted to the travel plate 28 in FIG. 1 is a chamber housing or hollow vessel 36 having an inner chamber 38 designed to receive a piston or plunger 40. The piston or displacement member has a flanged exterior end 42 which is larger than an aperture 44 in the top plate 30, so that movement of the piston 40 toward the base 12 is limited by the flanged end 42 contacting the top plate 30. The piston 40 has a head portion 46 which is designed to ride in sealing engagement within the cylindrical interior of the chamber 38. As shown in both FIGS. 1 and 2, a swivel mounting or head 48 is attached to the chamber housing 36. The mounting 48 is designed to rotate annularly with respect to the housing 36 in FIG. 1. A coupling 50 is located on the swivel mounting and is designed to receive a removable syringe tip 52. The swivel mounting 48 has a junction arrangement 54 to rotatably affix the mounting on the chamber housing 36. The junction arrangement 54 is designed in such a manner to allow fluid communication between the coupling 50 of the swivel mounting 48 and the passage 56 which is in fluid communication with the cylindrical chamber 38 in which the piston 40 resides. Consequently, there is fluid communication between the open end 58 of the syringe tip 52 and the cylindrical chamber 38 within the chamber housing 36. The swivel mounting 48 is designed as shown in FIG. 1 to provide for more convenient insertion and removal of the syringe tip 52 as will be explained. As shown in FIG. 2, located on the rear surface 60 of the travel plate 28 is a rack gear 62 having a plurality of teeth 64. Located in contacting relation with the rack gear teeth 64 is a pinion gear 68 having pinion gear teeth 66. The pinion gear 68 is rigidly mounted to a drive shaft 70 which is positioned and supported on and between the side panels 18 and 20 of the frame 14. Consequently, rotational movement of the drive shaft 70 will cause a corresponding movement of the rack gear 62 with the travel plate 28 which rides within the slots 26 of the side panels 18 and 20 of the frame 14. Located on each end of the drive shaft 70 are control knobs 72 which are designed to provide more accurate control movement of the travel plate 28 with the chamber housing 36 and syringe tip 52. Biasing means (not shown are used on the drive shaft to provide a slight resistance to the rotation of the knobs to enhance precise movement of the travel plate. Also secured to the travel plate 28 as shown in FIG. 1 is a dial micrometer 74 having a gauge reference end 76 and a scaled measuring face 78 with rotatable indicator dial 80. Consequently, downward movement of the travel plate 28 will result in the gauge end 76 of the micrometer contacting the top surface 13 of the base 12. Rotatably mounted on the base 12 in FIGS. 2 and 4 is a centrifuge tube holder 80 having a plurality of cavities 82 designed to receive a plurality of centrifuge tubes 84. The cylindrical holder 80 is connected to the base 12 by a screw or bolt 86 which also connects an indicator dial 88 to the base 12. Indicia 90 on the indicator dial wheel 88 are to identify and reference each of the centrifuge tubes 84. Turning to the operation of the present fractionation system 10, attention is directed to FIGS. 1 and 2. After centrifugation of a series of fluid samples has been completed, the centrifuge tubes 84 are placed within the respective apertures 82 in the tube holder 80 of the fractionator 10. The travel plate 28 is positioned in its upper location with the top edge of the travel plate 29 being closely adjacent the top plate 30 of the device 10. A pipette or syringe tip 52 having a series of ribs 51 for easier grasping is inserted on the coupling 50 of the swivel head 48 that is connected to the housing 36. As shown in FIG. 1, the swivel mounting 48 is pivoted essentially to the position shown in phantom whereby the syringe tip can be more easily snapped into place over the coupling 50. The syringe tip, once securely placed on the swivel mounting 48, is rotated down to the vertical position as shown in solid lines in FIG. 1. The operator uses the control knobs 72 of the drive shaft 70 to rotate the pinion gear 68 to move the rack gear 62 and the travel plate 28 in a direction toward the base 12 of the device. When the operator notes that the open end 58 of the syringe tip 52 barely comes in contact with the top surface of the fluid contents in the test tube 84, the operator records the reading on the micrometer scale 78. By precise movement of the control knobs 72 the operator moves the syringe tip into the fluid noting the differential reading on the micrometer scale. When the reading on the scale corresponds to the precise volume desired, downward movement of the syringe tip is stopped. Because the flanged end 42 of the plunger or piston 40 is restrained by the top plate 30 of the device, the downward movement of the chamber housing 36 in conjunction with the stationary piston head 46 will create a slight vacuum within the chamber 38. Further, the chamber 38 is made slightly larger than the size of the centrifuge tube 84 to enhance the creation of negative pressure in the chamber. Corresponding negative pressure which is caused within the chamber 38 will provide for the extraction of the fluid from the tube 84 as the syringe tip is lowered into the centrifuge tube. The fluid is withdrawn into the syringe tip off the very top surface of the level of contents of the tube. This alleviates any possible disturbance of subsequent fractions. Therefore, as the syringe tip is lowered, only the very top surface of the fluid is continually removed. Once the desired volume of fluid is received within the syringe tip 52, the control knobs 72 are used to raise the travel plate 28 and retract the syringe tip 52 from within the test tube 84. It should be noted that, as the chamber housing 36 is raised with the travel plate, the flanged end 42 of the piston 40 is also raised above the top plate 30 so that the fluid is not extracted from the syringe tip as it is being raised. The operator then moves the syringe tip 52 to the horizontal position shown in phantom in FIG. 1 and gently removes the syringe tip for placement in a storage rack. In addition to the convenience provided in the removal of the syringe tip, this horizontal position also prevents the fluid in the tip from running out as the tip is removed. A new syringe tip 52 is connected to the coupling 50 and the process repeated by extracting the next desired fraction from the contents within the centrifuge tube. Once all of the desired contents have been removed from the centrifuge tube, indicator plate 88 is rotated one notch to the next centrifuge tube to bring it in alignment with the syringe tip and the fractionation sequence is repeated on the full contents of another test tube. Although the present invention is directed primarily to a fractionation device providing accurate and reproducible fractionation of fluid in a very small or extremely small test tube, the overall device could be scaled larger in size with increasing diameter of the chamber 38 so that it could be used for larger centrifuge tubes in density gradient experiments, for example, in conjunction with swinging bucket rotors and preparative ultracentrifuges. This device would provide the necessary fractionation with extreme simplicity, accuracy and convenience as compared to prior art fractionation systems. The present invention describes a fractionation system device which allows for the fractionating of the contents in extremely small centrifuge tubes by the use of a simple mechanism that provides ultimate convenience and accuracy without the disadvantages of utilizing motors, pumps or electrical power as well as any connecting tube lines. The present invention is extremely versatile in the number of fractions collected and their size can be varied over a considerable range.
A device for the sequential fractionation of the contents of a centrifuge tube containing centrifugally separated contents utilizing a syringe-like apparatus. The present invention utilizes removable syringe tips that are mounted on a chamber housing for extraction and retention of a precise volume of centrifuged fluid from the centrifuge tube. The syringe-like apparatus is mounted to a frame in such a manner that the chamber housing is movable relative to the plunger or piston to permit precise movement of the chamber housing with the removable syringe tip into the centrifuge tube for delicate and precise removal of the desired fraction of the fluid. The syringe tips are removed with each fraction that is collected from the contents in the centrifuge tube and can be placed in a storage rack for subsequent analysis.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "BACKGROUND OF THE INVENTION The present invention is directed to sequential fractionation of the contents of a centrifuge tube after the centrifugation operation and, more particularly, is directed to a fractionation system that can remove very small fraction volumes accurately and reproducibly without undesirable mixing of the fractions or losses of the fractions in a transfer tube or line.", "The system operates without requiring a motor, pump or electrical power.", "After the centrifugation process, it is necessary to remove fractions of the separated contents in the fluid which has been subjected to centrifugation in order to proceed with the proper analysis of each separated constituent or level of fluid density.", "When using very small centrifuge tubes, the removal of precise small volumes or fractions of the fluid material from the centrifuge tube without losses or remixing presents a significant problem.", "Many types of devices have been developed for fractionating the contents of centrifuge tubes.", "One such approach utilized in a fractionation system is tube slicing whereby the tube is sequentially cut into segments in a special holder and knife assembly so that the fluid can be removed with a pipette from each segment after it is cut.", "Although tube slicing has been used with some success in separating the contents in extremely small test tubes into only two fractions, the system of tube slicing is entirely impractical and unsuccessful for small tube sequential fractionation process.", "Another process utilized for tube fractionation is puncturing whereby the tube is pierced with a hollow needle and the contents within the tube are collected slowly drop by drop as a result of applying a slight pressure to a space at the top of the tube.", "Another method for tube fractionation is the concept of displacement with the tube contents being displaced upward through a special cap assembly by injecting a heavy density fluid into the bottom of the tube by the use of a puncturing needle or by the use of a long capillary placed down into the centrifuge tube.", "A final primary method used in tube fractionation is aspiration whereby the tube contents are removed in sequential elements from the top of the tube.", "This is typically done by a syringe either hand held or in a special holder.", "Also a special assembly using a vacuum pump to withdraw fractions of the tube contents through a capillary placed into the open top of the tube enables fractionation by the aspiration principle.", "Typically, the methods presently used for tube fractionation provide a somewhat satisfactory approach when using larger centrifuge tubes of 5 milliliters or greater capacity, since losses of the fluid due to leaks or retention in the tubing connections can be tolerated.", "However, with respect to very small centrifuge tubes such as one holding as small as 0.175 milliliters of fluid, these methods of tube sequential fractionation do not provide satisfactory results.", "The volumes of fluid being handled in such small centrifuge tubes are so minute that losses due to leaks or retention in the tubing or as a result of remixing cannot be tolerated.", "SUMMARY OF THE INVENTION The present invention is directed to a sequential fractionation system utilizing a syringe-like apparatus whereby a chamber housing is connected to a frame in such a manner that the housing can be moved very precise distances relative to a plunger or piston within the chamber of the housing.", "Attached to the chamber housing are removable syringe tips that are used to collect the precise volume of fluid material for each sequential fractionation step.", "The present invention utilizes no motors or pumps eliminating the need for electrical power.", "Further, there is no need for connection tubing which would result in possible loss of the fluid volume remaining residually in the tubing.", "The principal unique feature of the present invention is the manner in which the syringe-like apparatus is used to withdraw aliquots of the fluid contained in the centrifuge tube.", "The syringe barrel incorporated into the chamber housing is moved downward relative to the syringe piston, which is restrained from moving downward by contact with the top plate of the fractionator.", "This is in contrast to the usual operation of syringes in which the piston is withdrawn from the barrel held in a fixed position.", "This novel mode of operation permits fluid aliquots to be removed from the centrifuge tube in a particularly advantageous manner as explained below.", "No fluid can be drawn into the syringe tip until it contacts the surface of the fluid in the tube.", "The start of the collection event cannot be initiated until contact is established by the syringe tip on the fluid surface.", "As the syringe tip and barrel are lowered, fluid is continuously withdrawn into the syringe tip only from the very surface of the contents within the tube which is a completely different operation from the prior art use of a syringe where the tip is immersed within the fluid and the fraction is withdrawn from below the surface rather than on the surface.", "The present method is essential to obtain sharp separation of fractions and to avoid mixing with fluid further down in the tube.", "To achieve the above described action of the present invention the volume swept out by the movement of the syringe barrel relative to the piston must be equal to or greater than the volume of the fraction to be collected.", "This requirement is best met by making the diameter of the syringe barrel slightly larger than the inside diameter of the centrifuge tube.", "If desired, the syringe diameter can be considerably larger than the tube diameter, but some air may be drawn into the syringe tip with the fluid volume.", "However, this will not adversely affect the accuracy of the volume of the fraction.", "The volume of the fraction collected is determined and controlled by measuring the distance which the chamber housing containing the syringe barrel is moved relative to its piston.", "This measurement is made conveniently by use of an attached measuring device which can accurately measure the movement of the chamber housing.", "The relationship between the distance moved and the actual volume collected can be calculated from a knowledge of the inside diameter of the centrifuge tube, but it is more accurate and convenient to determine the relationship by weighing fractions collected by movement of the chamber housing a particular distance in a preliminary fractionation using a centrifuge tube filled with water.", "When the desired volume of the fraction has been drawn into the syringe tip, the chamber housing containing the syringe barrel is now raised.", "Since the syringe piston is not restrained by contact with the top plate, the piston will move upward with the chamber housing.", "Thus, the fluid in the springe tip will remain in place undisturbed.", "The second unique feature of this invention is the fact that each fraction is contained entirely within the syringe tip and there is absolutely no loss due to leaks or retention of fluid in tubing connections.", "By removal of the tip, the fraction can be quantitatively transferred for subsequent use or analysis.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view of the fractionation apparatus;", "FIG. 2 is a partial sectional side elevational view of the apparatus;", "FIG. 3 is a top partial sectional view of the fractionation apparatus;", "and FIG. 4 is a sectional view taken along the lines 4--4 in FIG. 2. DETAILED DESCRIPTION OF THE INVENTION The fractionator device 10 of the present invention is shown in FIG. 1 having a base 12 on which is secured a frame member 14.", "At least three support pads or feet 15 are positioned in a balanced relationship on the bottom surface 34 of the base 12.", "As shown more clearly in FIG. 4, the frame member is an enlarged U-shaped one-piece member having a back portion 16 with integrally formed side panels 18 and 20 that extend perpendicular from the back portion 16.", "Located on the inside surface 22 of the side panels 18 and 20 and adjacent their free edges 24 are travel grooves 26.", "As shown in FIG. 1, a top plate 30 is secured over the frame member 14.", "The travel grooves 26 are designed to receive a travel plate 28 that operates in a manner which will be discussed below.", "Securely mounted to the travel plate 28 in FIG. 1 is a chamber housing or hollow vessel 36 having an inner chamber 38 designed to receive a piston or plunger 40.", "The piston or displacement member has a flanged exterior end 42 which is larger than an aperture 44 in the top plate 30, so that movement of the piston 40 toward the base 12 is limited by the flanged end 42 contacting the top plate 30.", "The piston 40 has a head portion 46 which is designed to ride in sealing engagement within the cylindrical interior of the chamber 38.", "As shown in both FIGS. 1 and 2, a swivel mounting or head 48 is attached to the chamber housing 36.", "The mounting 48 is designed to rotate annularly with respect to the housing 36 in FIG. 1. A coupling 50 is located on the swivel mounting and is designed to receive a removable syringe tip 52.", "The swivel mounting 48 has a junction arrangement 54 to rotatably affix the mounting on the chamber housing 36.", "The junction arrangement 54 is designed in such a manner to allow fluid communication between the coupling 50 of the swivel mounting 48 and the passage 56 which is in fluid communication with the cylindrical chamber 38 in which the piston 40 resides.", "Consequently, there is fluid communication between the open end 58 of the syringe tip 52 and the cylindrical chamber 38 within the chamber housing 36.", "The swivel mounting 48 is designed as shown in FIG. 1 to provide for more convenient insertion and removal of the syringe tip 52 as will be explained.", "As shown in FIG. 2, located on the rear surface 60 of the travel plate 28 is a rack gear 62 having a plurality of teeth 64.", "Located in contacting relation with the rack gear teeth 64 is a pinion gear 68 having pinion gear teeth 66.", "The pinion gear 68 is rigidly mounted to a drive shaft 70 which is positioned and supported on and between the side panels 18 and 20 of the frame 14.", "Consequently, rotational movement of the drive shaft 70 will cause a corresponding movement of the rack gear 62 with the travel plate 28 which rides within the slots 26 of the side panels 18 and 20 of the frame 14.", "Located on each end of the drive shaft 70 are control knobs 72 which are designed to provide more accurate control movement of the travel plate 28 with the chamber housing 36 and syringe tip 52.", "Biasing means (not shown are used on the drive shaft to provide a slight resistance to the rotation of the knobs to enhance precise movement of the travel plate.", "Also secured to the travel plate 28 as shown in FIG. 1 is a dial micrometer 74 having a gauge reference end 76 and a scaled measuring face 78 with rotatable indicator dial 80.", "Consequently, downward movement of the travel plate 28 will result in the gauge end 76 of the micrometer contacting the top surface 13 of the base 12.", "Rotatably mounted on the base 12 in FIGS. 2 and 4 is a centrifuge tube holder 80 having a plurality of cavities 82 designed to receive a plurality of centrifuge tubes 84.", "The cylindrical holder 80 is connected to the base 12 by a screw or bolt 86 which also connects an indicator dial 88 to the base 12.", "Indicia 90 on the indicator dial wheel 88 are to identify and reference each of the centrifuge tubes 84.", "Turning to the operation of the present fractionation system 10, attention is directed to FIGS. 1 and 2.", "After centrifugation of a series of fluid samples has been completed, the centrifuge tubes 84 are placed within the respective apertures 82 in the tube holder 80 of the fractionator 10.", "The travel plate 28 is positioned in its upper location with the top edge of the travel plate 29 being closely adjacent the top plate 30 of the device 10.", "A pipette or syringe tip 52 having a series of ribs 51 for easier grasping is inserted on the coupling 50 of the swivel head 48 that is connected to the housing 36.", "As shown in FIG. 1, the swivel mounting 48 is pivoted essentially to the position shown in phantom whereby the syringe tip can be more easily snapped into place over the coupling 50.", "The syringe tip, once securely placed on the swivel mounting 48, is rotated down to the vertical position as shown in solid lines in FIG. 1. The operator uses the control knobs 72 of the drive shaft 70 to rotate the pinion gear 68 to move the rack gear 62 and the travel plate 28 in a direction toward the base 12 of the device.", "When the operator notes that the open end 58 of the syringe tip 52 barely comes in contact with the top surface of the fluid contents in the test tube 84, the operator records the reading on the micrometer scale 78.", "By precise movement of the control knobs 72 the operator moves the syringe tip into the fluid noting the differential reading on the micrometer scale.", "When the reading on the scale corresponds to the precise volume desired, downward movement of the syringe tip is stopped.", "Because the flanged end 42 of the plunger or piston 40 is restrained by the top plate 30 of the device, the downward movement of the chamber housing 36 in conjunction with the stationary piston head 46 will create a slight vacuum within the chamber 38.", "Further, the chamber 38 is made slightly larger than the size of the centrifuge tube 84 to enhance the creation of negative pressure in the chamber.", "Corresponding negative pressure which is caused within the chamber 38 will provide for the extraction of the fluid from the tube 84 as the syringe tip is lowered into the centrifuge tube.", "The fluid is withdrawn into the syringe tip off the very top surface of the level of contents of the tube.", "This alleviates any possible disturbance of subsequent fractions.", "Therefore, as the syringe tip is lowered, only the very top surface of the fluid is continually removed.", "Once the desired volume of fluid is received within the syringe tip 52, the control knobs 72 are used to raise the travel plate 28 and retract the syringe tip 52 from within the test tube 84.", "It should be noted that, as the chamber housing 36 is raised with the travel plate, the flanged end 42 of the piston 40 is also raised above the top plate 30 so that the fluid is not extracted from the syringe tip as it is being raised.", "The operator then moves the syringe tip 52 to the horizontal position shown in phantom in FIG. 1 and gently removes the syringe tip for placement in a storage rack.", "In addition to the convenience provided in the removal of the syringe tip, this horizontal position also prevents the fluid in the tip from running out as the tip is removed.", "A new syringe tip 52 is connected to the coupling 50 and the process repeated by extracting the next desired fraction from the contents within the centrifuge tube.", "Once all of the desired contents have been removed from the centrifuge tube, indicator plate 88 is rotated one notch to the next centrifuge tube to bring it in alignment with the syringe tip and the fractionation sequence is repeated on the full contents of another test tube.", "Although the present invention is directed primarily to a fractionation device providing accurate and reproducible fractionation of fluid in a very small or extremely small test tube, the overall device could be scaled larger in size with increasing diameter of the chamber 38 so that it could be used for larger centrifuge tubes in density gradient experiments, for example, in conjunction with swinging bucket rotors and preparative ultracentrifuges.", "This device would provide the necessary fractionation with extreme simplicity, accuracy and convenience as compared to prior art fractionation systems.", "The present invention describes a fractionation system device which allows for the fractionating of the contents in extremely small centrifuge tubes by the use of a simple mechanism that provides ultimate convenience and accuracy without the disadvantages of utilizing motors, pumps or electrical power as well as any connecting tube lines.", "The present invention is extremely versatile in the number of fractions collected and their size can be varied over a considerable range." ]
RELATED APPLICATION [0001] The present application claims priority from U.S. Provisional Patent Application Ser. No. 61/437,790, filed on Jan. 31, 2011, which is incorporated herein by reference in its entirety. BACKGROUND [0002] The present application is generally related to an electrical housing assembly and, more particularly, to a housing assembly, electrical housing cap contact member and method, with applicability to a hostile operating environment. [0003] In drilling applications such as, for example, horizontal directional drilling, a drill rig located at an aboveground location is used to extend and retract a drill string that is connected to an inground tool such as, for example, a boring tool or reamer. It is often desirable to provide a flow of drilling fluid through the drill string to the inground tool. The latter emits the drilling fluid in some manner such that the drilling fluid thereafter flows up the borehole around the periphery of the drill string. The inground tool can house battery powered equipment such as, for example, a transmitter that can transmit an electromagnetic locating signal that can be received above the surface of the ground and provide information relating to the position and/or operating parameters of the inground tool that may be of interest. The downhole environment, however, can be particularly hostile with respect to the battery powered equipment. Generally, the battery powered equipment can be located in a tubular housing having endcaps that are intended to seal the housing. In this regard, the drilling fluid can be under some amount of pressure, even in the borehole after being emitted by the inground tool, and can find its way at least partially into the housing of the battery powered equipment along any available path of opportunity such as, for example, between the endcaps and the tubular body of the housing. [0004] Some embodiments of downhole battery powered equipment utilize the endcap as part of an electrical circuit. Since contamination and its sources are ubiquitous, for example, in the forms of dirt and fluid which can find its way into an interface between components such as a threaded connection, designs which rely on such connections for purposes of electrical contact can be subject to intermittent and/or open circuit conditions. Sources of contamination can include, by way of non-limiting example, handling by operators as well as the drilling or downhole environment. In this regard, Applicant has encountered this problem in an embodiment of battery powered equipment that utilizes threaded engagement between the endcap and body. That is, the connection between the threads of the cap and the threads of the body can become sufficiently fouled so as to interfere with an electrical connection between these components. [0005] Previous methods to alleviate the problem include adding a ball plunger placed radially into the threaded area of the tubular body such that the ball rides on the crest of a mating thread of the cap. Unfortunately, this method is recognized by Applicant as having numerous problems including difficulty in placing the threaded hole, adjusting the ball plunger, high cost and also being subject to fouling. In this latter regard, each ball plunger arrangement adds only one relatively complex electrical path between the cap and body. Further, this electrical path is subject to fouling at numerous points including between the plunger body and ball itself. [0006] The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings. SUMMARY [0007] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements. [0008] Generally, a housing assembly includes a housing body that is electrically conductive and defines a housing opening that leads into a housing cavity. The housing cavity can receive components that include but are not limited to a battery and related electrical components. In an embodiment, an endcap is electrically conductive and removably receivable on the housing body to close the housing opening. An elongated electrically conductive member can be resiliently captured between the housing body and the endcap to extend at least partially around the housing opening when the endcap is engaged with the housing body to form a plurality of electrical contacts between an inner surface of the housing body and the electrically conductive member and between the endcap and the electrically conductive member which can form part of an electrical circuit. In one feature, a spring member can be fixedly engaged to the endcap by a crimping arrangement that is integrally formed with the endcap such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of a battery received in the housing cavity when the endcap is received on the housing body. [0009] In an embodiment, an endcap arrangement is configured for an electrically conductive housing body having a housing opening that leads into a housing cavity. The endcap arrangement includes an endcap that is electrically conductive and removably receivable on the housing body to close the housing opening and an elongated electrically conductive member for resilient capture between the housing body and the endcap. The conductive member extends at least partially around the housing opening when the endcap is engaged with the housing body to form a plurality of electrical contacts between an inner surface of the housing body and the electrically conductive member and between the endcap and the electrically conductive member which can form part of an electrical circuit. [0010] In an embodiment, a housing assembly includes a housing body that is electrically conductive and defines a housing opening that leads into a housing cavity for receiving at least one battery. An endcap is electrically conductive and removably receivable on the housing body to close the housing opening. The endcap includes an integrally formed electrically conductive crimping arrangement for supporting an electrically conductive spring member in a crimped engagement such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of the battery when the endcap is received on the housing body. [0011] In an embodiment, an endcap arrangement is configured for an electrically conductive housing body having a housing opening that leads into a housing cavity. The endcap arrangement includes a spring member that is electrically conductive and an endcap that is electrically conductive and removably receivable on the housing body to close the housing opening. The endcap includes an integrally formed electrically conductive crimping arrangement for supporting the spring member in a crimped engagement such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of a battery that is received in the housing cavity when the endcap is received on the housing body. [0012] In an embodiment of a method according to the present disclosure, an electrical connection is formed between a housing body, that is electrically conductive and which defines a housing opening that leads into a housing cavity, and an endcap that is electrically conductive. An elongated electrically conductive member is resiliently captured between the housing body and the endcap to extend at least partially around the housing opening when the endcap is engaged with the housing body to form a plurality of electrical contacts between the housing body and the electrically conductive member and between the endcap and the electrically conductive member as part of an electrical circuit. [0013] In another embodiment of a method according to the present disclosure, an electrical connection is formed between an endcap that is electrically conductive and a battery that is received in a housing cavity of a housing body with the housing body defining a housing opening that leads into the housing cavity. A spring member is formed, which is electrically conductive, to include a base ring. A crimping arrangement is integrally formed as part of the endcap for crimpingly engaging the base ring such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of the battery received in the housing cavity when the endcap is received on the housing body to close the housing opening. [0014] In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following descriptions. BRIEF DESCRIPTIONS OF THE DRAWINGS [0015] Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be illustrative rather than limiting. [0016] FIG. 1 is a diagrammatic view, in elevation and partially in cross-section, of a battery powered assembly including a housing and endcap assembly according to the present disclosure. [0017] FIG. 2 is a diagrammatic view, in partial cross-section, of the assembly of FIG. 1 taken generally along a line 2 - 2 of FIG. 1 , shown here to illustrate further details with respect to the housing, an associated endcap and an electrically conductive resilient contact member. [0018] FIG. 3 diagrammatically illustrates another embodiment of the endcap and housing of FIGS. 1 and 2 , shown here to illustrate details of its structure. [0019] FIG. 4 is a diagrammatic end view of a peripheral groove, that can correspond to peripheral grooves shown in FIGS. 1-3 , which receive another embodiment of the electrically conductive resilient contact member. [0020] FIG. 5 is a perspective view of an embodiment of the endcap assembly of FIGS. 1 and 2 , shown here to illustrate details of its structure including an arrangement for engaging a contact spring. [0021] FIG. 6 is a perspective, exploded view of the endcap assembly of FIG. 5 . [0022] FIG. 7 is a diagrammatic view, in cross-section, of the endcap assembly of FIGS. 5 and 6 , illustrating a crimping ring in crimped engagement with a base coil of a spring to form an electrical connection therebetween. [0023] FIG. 8 is a diagrammatic, partially fragmentary view, in elevation, of the endcap of FIGS. 5-7 . DETAILED DESCRIPTION [0024] The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the described embodiments will be readily apparent to those skilled in the art and the generic principles taught herein may be applied to other embodiments. Thus, the present invention is not intended to be limited to the embodiment shown, but is to be accorded the widest scope consistent with the principles and features described herein including modifications and equivalents, as defined within the scope of the appended claims. It is noted that the drawings are not to scale and are diagrammatic in nature in a way that is thought to best illustrate features of interest. Descriptive terminology may be used with respect to these descriptions, however, this terminology has be adopted with the intent of facilitating the reader's understanding and is not intended as being limiting. Further, the figures are not to scale for purposes of illustrative clarity. [0025] In view of the foregoing, attention is now directed to FIG. 1 which is a diagrammatic partially cutaway view, in elevation, of one embodiment of a battery powered assembly that is generally indicated by the reference numeral 10 . Assembly 10 is suitable for use in downhole applications and produced according to the present disclosure. In the present embodiment, a housing 12 can be tubular (for example, cylindrical) although this is not a requirement and electrically conductive. The housing can be configured for threaded engagement with an endcap 14 . Threaded engagement, however, is not required and any suitable form of engagement between the endcap and housing may be utilized such as, for example, set screws, and/or bayonet mount so long as the endcap is removable for purposes of replacing battery cells 16 a and 16 b, shown in a series connection to make up an overall battery. Endcap 14 can define an O-ring groove 18 which receives an O-ring 20 therein, although other suitable forms of sealing may be utilized. A contact 24 electrically connects one terminal of the battery to a load 26 to provide electrical power to the load. Another contact 28 can electrically connect the other terminal of the battery to cap 14 . The load can be selected from a wide variety of different configurations but can include, by way of non-limiting example, sensors, associated electronics, transmitter electronics and/or receiver electronics. In the present embodiment, the batteries are shown as having the typical peripheral outline of well-known C size batteries although any suitable batteries can be used. Another terminal of the load can be electrically connected to housing 12 through a ground path 30 . When endcap 14 is in electrical contact with the housing, the electrical ground circuit to load 26 can be completed by passing through contact 28 , endcap 14 , housing 12 and contact 30 to reach the other terminal of the battery. As discussed above, Applicant has discovered that during inground service, the mating threads on the endcap and housing can become fouled and are not considered as a reliable expedient for conducting battery power even when a seal such as, for example, O-ring 20 is present. [0026] Turning now to FIG. 2 in conjunction with FIG. 1 , the former is a diagrammatic view in partial cross-section, taken along a line 2 - 2 in FIG. 1 . In order to overcome the foregoing problems and concerns, an electrically conductive, elongated resilient member 40 can be received in a peripheral groove 42 that can be defined by endcap 14 . The electrically conductive resilient contact member can have any suitable shape in cross-section such as, for example, circular, rectangular (including square), closed polygonal and can be formed from any suitable electrically conductive material such as, for example, copper alloys and other suitable metallic alloys of sufficient yield strength. To enhance the electrical contact, suitable platings can be employed such as, for example, electroless nickel. In an embodiment, resilient contact member 40 can be formed from straight stock by appropriate bending. In an installed condition that is best illustrated by FIG. 2 , resilient member 40 can be received within groove 42 defined by endcap 14 and captured between an inner surface 50 of housing 12 and a floor 52 of groove 42 of the endcap. It should be appreciated that groove 42 can be located on an inboard or inward side of O-ring seal 20 to further reduce or limit the potential for fouling. Resilient member 40 can readily be expanded for purposes of installation into groove 42 . It should therefore be appreciated that the view of FIG. 2 illustrates the resilient member in a deformed state, although its appearance in an undeformed state is similar. [0027] As is best seen in FIG. 2 , resilient contact member 40 includes an elongated body that can extend more than one-half of the way (i.e., substantially) around a circular periphery of endcap 14 for purposes of retaining the member in groove 42 when the endcap is disengaged from the housing, although any suitable amount of arc length can be used by the resilient contact member within groove 42 . Opposing ends 56 a and 56 b of the resilient contact member can be placed in a significantly spaced apart disposition with respect to one another in the groove or in near physical contact, as installed, while facilitating electrical continuity between the endcap and housing. In some embodiments, the opposing ends can overlap when installed at least to a limited extent. The resilient contact member can be formed to define a plurality of segments such that the segments adjoin to define electrical contacts against inner surface 50 of housing 12 . In the example of FIG. 2 , four contacts 60 are made with the inner surface of the housing using five segments. Simultaneously, opposing ends 56 a and 56 b of the resilient spring member can be formed to resiliently electrically contact floor 52 of groove 42 in the endcap. Additional electrical contact points 62 with the floor of groove 42 , which may be referred to as intermediate electrical contact points, can be defined along the length of at least some of the segments. In some embodiments, electrical contacts defined by adjoining segments can resiliently contact the floor of groove 42 and/or inner surface 50 of the housing in a manner that will be further described below. [0028] It should be appreciated that the cooperating geometry between the resilient contact member and the endcap, as well as the cooperating geometry between the resilient contact member and housing can be configured so as to generate what may be referred to as theoretical points of electrical contact. For example, if the resilient member includes a peripheral shape in cross-section that is defined by one or more curves, such theoretical points of electrical contact can be defined. More particular cross-sectional shapes which generate theoretical points of contact include, by way of example, circular and elliptical shapes. Such theoretical contact points can be useful in causing the mating/engaging geometry to produce a relatively higher level of contact force or stress as opposed to area or linear contacts that are purposefully defined as such from the standpoint of the design. The term theoretical electrical contact, as used herein, designates an attempt to form a point contact. Of course, since the mathematical definition of a point does not include an area, a theoretical point contact includes some area at least from a practical standpoint. The term electrical contact, as used hereinafter, can refer to such theoretical electrical contacts. The relatively higher levels of contact stress for theoretical electrical contacts may render theoretical contacts even less prone to fouling. The use of multiple contact points both inward engaging the endcap and outward engaging the housing can still further enhance the quality of the electrical circuit that is formed between the endcap and housing by the resilient contact member. Thus, resilient contact member 40 and its introduction produces a reliable electrical connection from battery cell 16 b, through contact 28 , through endcap 14 , through resilient contact member 40 , through housing 12 , through ground contact 30 and to load 26 . [0029] In the present example, five segments have been illustrated as forming resilient contact member 40 , however, any suitable number of fewer or greater segments can be employed. It is noted that the embodiment illustrated by FIGS. 1 and 2 includes a symmetrical shape having a pair of end segments connected to a pair of intermediate segments and a middle segment connecting the intermediate segments. It is noted, however, that such symmetry is not required. [0030] Referring to FIG. 3 , another embodiment of the endcap and housing of FIGS. 1 and 2 is shown in a diagrammatic fragmentary view and generally referred to by the reference number 300 . A peripheral groove 302 is defined by housing 12 and receives resilient spring contact member 40 . The latter can initially be compressed to an extent that is sufficient for purposes of installation into the peripheral groove. [0031] Referring to FIG. 4 , a diagrammatic view of either groove 42 of FIG. 2 or groove 302 of FIG. 3 is seen having a resilient contact member 400 received therein. In this embodiment, resilient contact member 400 includes what may be referred to as a zig-zag configuration which provides a plurality of electrical contacts (theoretical or otherwise) to each of floor 52 of the endcap and inner surface 50 of the housing. It should be appreciated that the segments can be of any suitable length including of different lengths and/or of equal lengths. Accordingly, it should be appreciated that the resilient contact member can be configured in a virtually unlimited number of ways while remaining within the scope of the teachings that have been brought to light herein. [0032] FIGS. 5 and 6 provide additional diagrammatic perspective views of an embodiment of the endcap, generally indicated by the reference number 14 ′, including associated components and resilient contact member 40 . FIGS. 7 and 8 provide additional diagrammatic fragmentary views, in elevation. FIGS. 6-8 , in particular, illustrate a crimping member 500 which can cooperate with a hub 502 to define a retaining recess which receives a base loop 504 ( FIG. 6 ) of a conical coil spring 28 ′. It should be appreciated that the use of a conical coil spring is not intended as limiting and that any suitable form of resilient contact member may be used. Crimping member 500 can be continuous and circular, in one embodiment, in the form of a crimping ring. The latter is illustrated prior to crimping in FIG. 6 and post-crimping in FIGS. 7 and 8 . In another embodiment, a plurality of crimping members in the form of crimping tabs can be provided in a spaced apart relationship around the periphery of hub 502 . The appearance of FIGS. 7 and 8 can be representative of the appearance of such crimping tabs. It should be appreciated that the use of the crimping members such as the crimping ring and crimping tabs can provide a remarkably strong crimping force against base loop 504 for purposes of maintaining reliable electrical contact. An embodiment of any endcap described herein can be provided for use with a pre-existing housing body. For example, one embodiment can include an endcap body configured for supporting resilient contact member 40 along with the resilient contact member itself. Another embodiment can include an endcap body configured for crimping engagement with spring member 28 ′ along with the spring member itself. Still another embodiment can include the endcap body, the resilient contact member and the spring member. Further, either the resilient contact member and/or spring member can be provided independently for replacement purposes. [0033] The use of the resilient contact member, as taught herein, overcomes the problems of the prior art while providing ease of installation. Further, there is no need for subsequent adjustment, it is low in cost, while providing a remarkable resistance to fouling and generates multiple contact points to each of the endcap and the housing. The resilient contact member can perform its intended function even when the endcap is not fully seated on the housing. All that is required is that the resilient contact member is captured between continuous surfaces defined by the endcap and the housing. For example, in the embodiment of FIG. 1 , the endcap can be positioned within a range of lateral positions (left to right in the view of the figure) relative to the housing while still providing a plurality of electrical contacts between the continuous inner surface of the housing and the floor of the endcap groove. Of course, rotation of the contact member during installation or inground operation likewise does not affect its formation of the desired plurality of electrical contacts. Even if the endcap inadvertently becomes somewhat loose during operation, electrical contacts are maintained. It is noted that a wide variety of materials are suitable for the contact surfaces of the housing and endcap. In some embodiments, a corrosion resistant material, which can be a coating, can be applied to enhance conductivity. The material can be selected to have sufficient strength to withstand the stress resulting from the electrical contact loads. [0034] The foregoing description of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form or forms disclosed, and other modifications and variations may be possible in light of the above teachings wherein those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof.
A hostile environment electrical housing, associated endcap and method are described. A housing body is electrically conductive and defines a housing opening that leads into a housing cavity. An elongated electrically conductive member can be resiliently captured between the housing to form a plurality of electrical contacts between the housing body and the endcap as part of an electrical circuit. A spring can be fixedly engaged to the endcap by a crimping arrangement that is integrally formed with the endcap. An endcap assembly including the endcap and the elongated electrically conductive member can be provided for installation on a pre-existing housing body.
Provide a concise summary of the essential information conveyed in the given context.
[ "RELATED APPLICATION [0001] The present application claims priority from U.S. Provisional Patent Application Ser.", "No. 61/437,790, filed on Jan. 31, 2011, which is incorporated herein by reference in its entirety.", "BACKGROUND [0002] The present application is generally related to an electrical housing assembly and, more particularly, to a housing assembly, electrical housing cap contact member and method, with applicability to a hostile operating environment.", "[0003] In drilling applications such as, for example, horizontal directional drilling, a drill rig located at an aboveground location is used to extend and retract a drill string that is connected to an inground tool such as, for example, a boring tool or reamer.", "It is often desirable to provide a flow of drilling fluid through the drill string to the inground tool.", "The latter emits the drilling fluid in some manner such that the drilling fluid thereafter flows up the borehole around the periphery of the drill string.", "The inground tool can house battery powered equipment such as, for example, a transmitter that can transmit an electromagnetic locating signal that can be received above the surface of the ground and provide information relating to the position and/or operating parameters of the inground tool that may be of interest.", "The downhole environment, however, can be particularly hostile with respect to the battery powered equipment.", "Generally, the battery powered equipment can be located in a tubular housing having endcaps that are intended to seal the housing.", "In this regard, the drilling fluid can be under some amount of pressure, even in the borehole after being emitted by the inground tool, and can find its way at least partially into the housing of the battery powered equipment along any available path of opportunity such as, for example, between the endcaps and the tubular body of the housing.", "[0004] Some embodiments of downhole battery powered equipment utilize the endcap as part of an electrical circuit.", "Since contamination and its sources are ubiquitous, for example, in the forms of dirt and fluid which can find its way into an interface between components such as a threaded connection, designs which rely on such connections for purposes of electrical contact can be subject to intermittent and/or open circuit conditions.", "Sources of contamination can include, by way of non-limiting example, handling by operators as well as the drilling or downhole environment.", "In this regard, Applicant has encountered this problem in an embodiment of battery powered equipment that utilizes threaded engagement between the endcap and body.", "That is, the connection between the threads of the cap and the threads of the body can become sufficiently fouled so as to interfere with an electrical connection between these components.", "[0005] Previous methods to alleviate the problem include adding a ball plunger placed radially into the threaded area of the tubular body such that the ball rides on the crest of a mating thread of the cap.", "Unfortunately, this method is recognized by Applicant as having numerous problems including difficulty in placing the threaded hole, adjusting the ball plunger, high cost and also being subject to fouling.", "In this latter regard, each ball plunger arrangement adds only one relatively complex electrical path between the cap and body.", "Further, this electrical path is subject to fouling at numerous points including between the plunger body and ball itself.", "[0006] The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive.", "Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.", "SUMMARY [0007] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope.", "In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.", "[0008] Generally, a housing assembly includes a housing body that is electrically conductive and defines a housing opening that leads into a housing cavity.", "The housing cavity can receive components that include but are not limited to a battery and related electrical components.", "In an embodiment, an endcap is electrically conductive and removably receivable on the housing body to close the housing opening.", "An elongated electrically conductive member can be resiliently captured between the housing body and the endcap to extend at least partially around the housing opening when the endcap is engaged with the housing body to form a plurality of electrical contacts between an inner surface of the housing body and the electrically conductive member and between the endcap and the electrically conductive member which can form part of an electrical circuit.", "In one feature, a spring member can be fixedly engaged to the endcap by a crimping arrangement that is integrally formed with the endcap such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of a battery received in the housing cavity when the endcap is received on the housing body.", "[0009] In an embodiment, an endcap arrangement is configured for an electrically conductive housing body having a housing opening that leads into a housing cavity.", "The endcap arrangement includes an endcap that is electrically conductive and removably receivable on the housing body to close the housing opening and an elongated electrically conductive member for resilient capture between the housing body and the endcap.", "The conductive member extends at least partially around the housing opening when the endcap is engaged with the housing body to form a plurality of electrical contacts between an inner surface of the housing body and the electrically conductive member and between the endcap and the electrically conductive member which can form part of an electrical circuit.", "[0010] In an embodiment, a housing assembly includes a housing body that is electrically conductive and defines a housing opening that leads into a housing cavity for receiving at least one battery.", "An endcap is electrically conductive and removably receivable on the housing body to close the housing opening.", "The endcap includes an integrally formed electrically conductive crimping arrangement for supporting an electrically conductive spring member in a crimped engagement such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of the battery when the endcap is received on the housing body.", "[0011] In an embodiment, an endcap arrangement is configured for an electrically conductive housing body having a housing opening that leads into a housing cavity.", "The endcap arrangement includes a spring member that is electrically conductive and an endcap that is electrically conductive and removably receivable on the housing body to close the housing opening.", "The endcap includes an integrally formed electrically conductive crimping arrangement for supporting the spring member in a crimped engagement such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of a battery that is received in the housing cavity when the endcap is received on the housing body.", "[0012] In an embodiment of a method according to the present disclosure, an electrical connection is formed between a housing body, that is electrically conductive and which defines a housing opening that leads into a housing cavity, and an endcap that is electrically conductive.", "An elongated electrically conductive member is resiliently captured between the housing body and the endcap to extend at least partially around the housing opening when the endcap is engaged with the housing body to form a plurality of electrical contacts between the housing body and the electrically conductive member and between the endcap and the electrically conductive member as part of an electrical circuit.", "[0013] In another embodiment of a method according to the present disclosure, an electrical connection is formed between an endcap that is electrically conductive and a battery that is received in a housing cavity of a housing body with the housing body defining a housing opening that leads into the housing cavity.", "A spring member is formed, which is electrically conductive, to include a base ring.", "A crimping arrangement is integrally formed as part of the endcap for crimpingly engaging the base ring such that the spring member maintains electrical contact with the endcap and a distal end of the spring member electrically contacts one terminal of the battery received in the housing cavity when the endcap is received on the housing body to close the housing opening.", "[0014] In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following descriptions.", "BRIEF DESCRIPTIONS OF THE DRAWINGS [0015] Exemplary embodiments are illustrated in referenced figures of the drawings.", "It is intended that the embodiments and figures disclosed herein are to be illustrative rather than limiting.", "[0016] FIG. 1 is a diagrammatic view, in elevation and partially in cross-section, of a battery powered assembly including a housing and endcap assembly according to the present disclosure.", "[0017] FIG. 2 is a diagrammatic view, in partial cross-section, of the assembly of FIG. 1 taken generally along a line 2 - 2 of FIG. 1 , shown here to illustrate further details with respect to the housing, an associated endcap and an electrically conductive resilient contact member.", "[0018] FIG. 3 diagrammatically illustrates another embodiment of the endcap and housing of FIGS. 1 and 2 , shown here to illustrate details of its structure.", "[0019] FIG. 4 is a diagrammatic end view of a peripheral groove, that can correspond to peripheral grooves shown in FIGS. 1-3 , which receive another embodiment of the electrically conductive resilient contact member.", "[0020] FIG. 5 is a perspective view of an embodiment of the endcap assembly of FIGS. 1 and 2 , shown here to illustrate details of its structure including an arrangement for engaging a contact spring.", "[0021] FIG. 6 is a perspective, exploded view of the endcap assembly of FIG. 5 .", "[0022] FIG. 7 is a diagrammatic view, in cross-section, of the endcap assembly of FIGS. 5 and 6 , illustrating a crimping ring in crimped engagement with a base coil of a spring to form an electrical connection therebetween.", "[0023] FIG. 8 is a diagrammatic, partially fragmentary view, in elevation, of the endcap of FIGS. 5-7 .", "DETAILED DESCRIPTION [0024] The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements.", "Various modifications to the described embodiments will be readily apparent to those skilled in the art and the generic principles taught herein may be applied to other embodiments.", "Thus, the present invention is not intended to be limited to the embodiment shown, but is to be accorded the widest scope consistent with the principles and features described herein including modifications and equivalents, as defined within the scope of the appended claims.", "It is noted that the drawings are not to scale and are diagrammatic in nature in a way that is thought to best illustrate features of interest.", "Descriptive terminology may be used with respect to these descriptions, however, this terminology has be adopted with the intent of facilitating the reader's understanding and is not intended as being limiting.", "Further, the figures are not to scale for purposes of illustrative clarity.", "[0025] In view of the foregoing, attention is now directed to FIG. 1 which is a diagrammatic partially cutaway view, in elevation, of one embodiment of a battery powered assembly that is generally indicated by the reference numeral 10 .", "Assembly 10 is suitable for use in downhole applications and produced according to the present disclosure.", "In the present embodiment, a housing 12 can be tubular (for example, cylindrical) although this is not a requirement and electrically conductive.", "The housing can be configured for threaded engagement with an endcap 14 .", "Threaded engagement, however, is not required and any suitable form of engagement between the endcap and housing may be utilized such as, for example, set screws, and/or bayonet mount so long as the endcap is removable for purposes of replacing battery cells 16 a and 16 b, shown in a series connection to make up an overall battery.", "Endcap 14 can define an O-ring groove 18 which receives an O-ring 20 therein, although other suitable forms of sealing may be utilized.", "A contact 24 electrically connects one terminal of the battery to a load 26 to provide electrical power to the load.", "Another contact 28 can electrically connect the other terminal of the battery to cap 14 .", "The load can be selected from a wide variety of different configurations but can include, by way of non-limiting example, sensors, associated electronics, transmitter electronics and/or receiver electronics.", "In the present embodiment, the batteries are shown as having the typical peripheral outline of well-known C size batteries although any suitable batteries can be used.", "Another terminal of the load can be electrically connected to housing 12 through a ground path 30 .", "When endcap 14 is in electrical contact with the housing, the electrical ground circuit to load 26 can be completed by passing through contact 28 , endcap 14 , housing 12 and contact 30 to reach the other terminal of the battery.", "As discussed above, Applicant has discovered that during inground service, the mating threads on the endcap and housing can become fouled and are not considered as a reliable expedient for conducting battery power even when a seal such as, for example, O-ring 20 is present.", "[0026] Turning now to FIG. 2 in conjunction with FIG. 1 , the former is a diagrammatic view in partial cross-section, taken along a line 2 - 2 in FIG. 1 .", "In order to overcome the foregoing problems and concerns, an electrically conductive, elongated resilient member 40 can be received in a peripheral groove 42 that can be defined by endcap 14 .", "The electrically conductive resilient contact member can have any suitable shape in cross-section such as, for example, circular, rectangular (including square), closed polygonal and can be formed from any suitable electrically conductive material such as, for example, copper alloys and other suitable metallic alloys of sufficient yield strength.", "To enhance the electrical contact, suitable platings can be employed such as, for example, electroless nickel.", "In an embodiment, resilient contact member 40 can be formed from straight stock by appropriate bending.", "In an installed condition that is best illustrated by FIG. 2 , resilient member 40 can be received within groove 42 defined by endcap 14 and captured between an inner surface 50 of housing 12 and a floor 52 of groove 42 of the endcap.", "It should be appreciated that groove 42 can be located on an inboard or inward side of O-ring seal 20 to further reduce or limit the potential for fouling.", "Resilient member 40 can readily be expanded for purposes of installation into groove 42 .", "It should therefore be appreciated that the view of FIG. 2 illustrates the resilient member in a deformed state, although its appearance in an undeformed state is similar.", "[0027] As is best seen in FIG. 2 , resilient contact member 40 includes an elongated body that can extend more than one-half of the way (i.e., substantially) around a circular periphery of endcap 14 for purposes of retaining the member in groove 42 when the endcap is disengaged from the housing, although any suitable amount of arc length can be used by the resilient contact member within groove 42 .", "Opposing ends 56 a and 56 b of the resilient contact member can be placed in a significantly spaced apart disposition with respect to one another in the groove or in near physical contact, as installed, while facilitating electrical continuity between the endcap and housing.", "In some embodiments, the opposing ends can overlap when installed at least to a limited extent.", "The resilient contact member can be formed to define a plurality of segments such that the segments adjoin to define electrical contacts against inner surface 50 of housing 12 .", "In the example of FIG. 2 , four contacts 60 are made with the inner surface of the housing using five segments.", "Simultaneously, opposing ends 56 a and 56 b of the resilient spring member can be formed to resiliently electrically contact floor 52 of groove 42 in the endcap.", "Additional electrical contact points 62 with the floor of groove 42 , which may be referred to as intermediate electrical contact points, can be defined along the length of at least some of the segments.", "In some embodiments, electrical contacts defined by adjoining segments can resiliently contact the floor of groove 42 and/or inner surface 50 of the housing in a manner that will be further described below.", "[0028] It should be appreciated that the cooperating geometry between the resilient contact member and the endcap, as well as the cooperating geometry between the resilient contact member and housing can be configured so as to generate what may be referred to as theoretical points of electrical contact.", "For example, if the resilient member includes a peripheral shape in cross-section that is defined by one or more curves, such theoretical points of electrical contact can be defined.", "More particular cross-sectional shapes which generate theoretical points of contact include, by way of example, circular and elliptical shapes.", "Such theoretical contact points can be useful in causing the mating/engaging geometry to produce a relatively higher level of contact force or stress as opposed to area or linear contacts that are purposefully defined as such from the standpoint of the design.", "The term theoretical electrical contact, as used herein, designates an attempt to form a point contact.", "Of course, since the mathematical definition of a point does not include an area, a theoretical point contact includes some area at least from a practical standpoint.", "The term electrical contact, as used hereinafter, can refer to such theoretical electrical contacts.", "The relatively higher levels of contact stress for theoretical electrical contacts may render theoretical contacts even less prone to fouling.", "The use of multiple contact points both inward engaging the endcap and outward engaging the housing can still further enhance the quality of the electrical circuit that is formed between the endcap and housing by the resilient contact member.", "Thus, resilient contact member 40 and its introduction produces a reliable electrical connection from battery cell 16 b, through contact 28 , through endcap 14 , through resilient contact member 40 , through housing 12 , through ground contact 30 and to load 26 .", "[0029] In the present example, five segments have been illustrated as forming resilient contact member 40 , however, any suitable number of fewer or greater segments can be employed.", "It is noted that the embodiment illustrated by FIGS. 1 and 2 includes a symmetrical shape having a pair of end segments connected to a pair of intermediate segments and a middle segment connecting the intermediate segments.", "It is noted, however, that such symmetry is not required.", "[0030] Referring to FIG. 3 , another embodiment of the endcap and housing of FIGS. 1 and 2 is shown in a diagrammatic fragmentary view and generally referred to by the reference number 300 .", "A peripheral groove 302 is defined by housing 12 and receives resilient spring contact member 40 .", "The latter can initially be compressed to an extent that is sufficient for purposes of installation into the peripheral groove.", "[0031] Referring to FIG. 4 , a diagrammatic view of either groove 42 of FIG. 2 or groove 302 of FIG. 3 is seen having a resilient contact member 400 received therein.", "In this embodiment, resilient contact member 400 includes what may be referred to as a zig-zag configuration which provides a plurality of electrical contacts (theoretical or otherwise) to each of floor 52 of the endcap and inner surface 50 of the housing.", "It should be appreciated that the segments can be of any suitable length including of different lengths and/or of equal lengths.", "Accordingly, it should be appreciated that the resilient contact member can be configured in a virtually unlimited number of ways while remaining within the scope of the teachings that have been brought to light herein.", "[0032] FIGS. 5 and 6 provide additional diagrammatic perspective views of an embodiment of the endcap, generally indicated by the reference number 14 ′, including associated components and resilient contact member 40 .", "FIGS. 7 and 8 provide additional diagrammatic fragmentary views, in elevation.", "FIGS. 6-8 , in particular, illustrate a crimping member 500 which can cooperate with a hub 502 to define a retaining recess which receives a base loop 504 ( FIG. 6 ) of a conical coil spring 28 ′.", "It should be appreciated that the use of a conical coil spring is not intended as limiting and that any suitable form of resilient contact member may be used.", "Crimping member 500 can be continuous and circular, in one embodiment, in the form of a crimping ring.", "The latter is illustrated prior to crimping in FIG. 6 and post-crimping in FIGS. 7 and 8 .", "In another embodiment, a plurality of crimping members in the form of crimping tabs can be provided in a spaced apart relationship around the periphery of hub 502 .", "The appearance of FIGS. 7 and 8 can be representative of the appearance of such crimping tabs.", "It should be appreciated that the use of the crimping members such as the crimping ring and crimping tabs can provide a remarkably strong crimping force against base loop 504 for purposes of maintaining reliable electrical contact.", "An embodiment of any endcap described herein can be provided for use with a pre-existing housing body.", "For example, one embodiment can include an endcap body configured for supporting resilient contact member 40 along with the resilient contact member itself.", "Another embodiment can include an endcap body configured for crimping engagement with spring member 28 ′ along with the spring member itself.", "Still another embodiment can include the endcap body, the resilient contact member and the spring member.", "Further, either the resilient contact member and/or spring member can be provided independently for replacement purposes.", "[0033] The use of the resilient contact member, as taught herein, overcomes the problems of the prior art while providing ease of installation.", "Further, there is no need for subsequent adjustment, it is low in cost, while providing a remarkable resistance to fouling and generates multiple contact points to each of the endcap and the housing.", "The resilient contact member can perform its intended function even when the endcap is not fully seated on the housing.", "All that is required is that the resilient contact member is captured between continuous surfaces defined by the endcap and the housing.", "For example, in the embodiment of FIG. 1 , the endcap can be positioned within a range of lateral positions (left to right in the view of the figure) relative to the housing while still providing a plurality of electrical contacts between the continuous inner surface of the housing and the floor of the endcap groove.", "Of course, rotation of the contact member during installation or inground operation likewise does not affect its formation of the desired plurality of electrical contacts.", "Even if the endcap inadvertently becomes somewhat loose during operation, electrical contacts are maintained.", "It is noted that a wide variety of materials are suitable for the contact surfaces of the housing and endcap.", "In some embodiments, a corrosion resistant material, which can be a coating, can be applied to enhance conductivity.", "The material can be selected to have sufficient strength to withstand the stress resulting from the electrical contact loads.", "[0034] The foregoing description of the invention has been presented for purposes of illustration and description.", "It is not intended to be exhaustive or to limit the invention to the precise form or forms disclosed, and other modifications and variations may be possible in light of the above teachings wherein those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof." ]
RELATED PATENT APPLICATION The present invention relates to U.S. patent application entitled “USE ALLOWED PRIORITY LEVEL FOR ROUTING DECISION IN SIMA NETWORKS”, Ser. No. 09/146,862 filed Sep. 3, 1998; U.S. patent application entitled “USE OF PRIORITIES DEFINED BY A CUSTOMER IN A SIMA NETWORK”, Ser. No. 09/159,005 filed Sep. 23, 1998; U.S. patent application entitled “NOMINAL BIT RATE NETWORK SERVICE”, Ser. No. 08/821,273, filed Mar. 20, 1997; U.S. patent application entitled “CELL SCHEDULING SYSTEM AND METHOD FOR NETWORK NODES”, Ser. No. 08/822,266, filed Mar. 20, 1997, now U.S. Pat. No. 6,081,505; and U.S. patent application entitled “ACCOUNTING SYSTEM AND METHOD FOR A NOMINAL BIT RATE NETWORK SERVICE”, Ser. No. 08/822,270, filed Mar. 20, 1997, now U.S. Pat. No. 6,047,326; the subject matter of which are hereby incorporated by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates in general to communication systems, and more particularly, to a method and system for managing information communicated over a Simple Integrated Media Access (SIMA) network with a Nominal Bit Rate (NBR) pool. 2. Description of Related Art Simple Integrated Media Access (SIMA) is a new way of introducing new properties for packet-based data networks, such as TCP/IP or ATM networks. The basic idea of SIMA relies on the use of eight packet-discarding priority levels, as described in details in the above-mentioned patent applications, entitled “NOMINAL BIT RATE NETWORK SERVICE”, NC 7664, Ser. No. 08/821,273, filed Mar.20, 1997; U.S. patent application entitled “CELL SCHEDULING SYSTEM AND METHOD FOR NETWORK NODES”, NC 7665, Ser. No. 08/822,266, filed Mar. 20, 1997; and U.S. patent application entitled “ACCOUNTING SYSTEM AND METHOD FOR A NOMINAL BIT RATE NETWORK SERVICE”, NC 7701, Ser. No. 08/822,270, filed Mar. 20, 1997; the subject matter of which are hereby incorporated by reference. Every data packet is equipped with a priority level (PL) that can be an integer between 0 and 7. In the latest SIMA literature, the term “priority level” is often replaced by “drop preference” which has the same meaning as “priority level”. In a SIMA network, priority is used for selecting packets that are discarded during congestion of a network node. The priority is determined from the ratio of a momentary actual bit rate of the source (a customer) to the Nominal Bit Rate (NBR) assigned to the source (the customer). This determination is performed in a network access node that is the first network element to receive a packet from a customer equipment. A conventional way of managing customer charging on Internet is based on flat- rate, that is, each customer pays a monthly fee and gets certain Internet service. Since the management of a more complicated charging scheme for every individual customer means excessive management and cost, the flat-rate charging scheme is currently a prevalent way. SIMA network with this type of simple flat-rate charging scheme is presently available for the customer. The monthly fee, for example $X, is translated to a certain NBR. The available network capacity is then divided among competing connections proportional to the NBR of each connection or customer. With typical data applications and low bit rate real-time applications, this SIMA network system may work properly. However, if a SIMA customer has, for instance, a permanent or flat-rate NBR of 50 kbit/s, and he/she desires to send a video stream with a speed of 500 kbit/s (i.e. higher NBR), the outcome could be totally unsatisfactory in using the simple flat-rate charging scheme. The priority of the packets (or called frames or cells) of information will be so low that the packet loss ratio will be very high. Consequently, the video quality will be very low for any practical purpose. This problem can be solved by combining the flat rate scheme and a time-dependent charging scheme presented in the above-mentioned U.S. patent applications. Although this solution is technically quite simple, it requires many changes in customer's management and charging. For example, the customer has to keep track of what period of time that he/she has requested for what NBR, other than the permanent NBR, and how much it is for such NBR, etc. Accordingly, there is a need in the communication industry for a network management architecture and method that can combine the simplicity of flat-rate charging and the flexibility of time-dependent scheme into a SIMA network system. SUMMARY OF THE INVENTION The present invention relates to communication systems, and more particularly, to a method and system for managing information communicated over a SIMA network with a Nominal Bit Rate (NBR) pool. To overcome the limitations in the prior art described above, and to overcome other limitations that will become apparent upon reading and understanding the present specification, the present invention discloses a NBR pool that is used with SIMA network so that a customer of a network service provider is allowed to change his/her NBR without any actual time-dependent charging. The NBR pool method and apparatus of the present invention has both the simplicity of flat-rate charging and the flexibility of time-dependent scheme. The advantage of this system is that a “pure” flat-rate charging is possible even though the customer is allowed to change the NBR. In one embodiment of the present invention, a NBR pool is established such that each SIMA customer has a permanent NBR based on the monthly fee (flat or fixed fee) or some other fee schedules, such as semi-monthly, weekly, or annual fees, etc. In addition, the customer is allowed to momentarily use a higher NBR, but only during a limited time period and for a limited amount. Further in one embodiment of the present invention, the NBR pool unit controls an actual NBR used for determining the SIMA priorities based on a NBR desired by the customer, a permanent NBR, and the maximum pool size. The present invention also relates to a method of charging a flat-rate for a customer's use of a communication network and providing variable actual nominal bit rate (NBR r ) to suit for momentarily desired nominal bit rates requested by the customer. In one embodiment, a method of generating an actual Nominal Bit Rate (NBRr r ) to determine a priority in a SIMA network for a customer which desires a NBR d to transmit a packet of information via the network, comprises: providing a flat-rate Nominal Bit Rate (NBR p ) for the customer, the NBR p being predefined between the customer and the network; providing a NBR pool having a maximum pool size (S max ), the S max being predefined between the customer and the network, the NBR pool being filled by a customer's NBR p and depleted by a customer's NBR d ; and generating the NBR r based on the NBR p , the S max , and the NBR d . Still in one embodiment of the present invention, the generating NBR r includes determining a size of the NBR pool, wherein when the NBR pool is empty, the NBR r is the NBR p ; when the size of the NBR pool is not smaller than the maximum pool size S max , the NBR r is the NBR d ; when the size of the NBR pool is smaller than the maximum pool size S max but not empty, the NBR r is a sum of the NBR p and a NBR pool rate; the NBR pool rate being determined by the size of the NBR pool being divided by a time interval (Δt), the time interval being a time period for the network to change the actual Nominal Bit Rate. Further in one embodiment of the present invention, the time interval is approximately one minute. Yet in one embodiment of the present invention, the maximum pool size is approximately one giga bits. The present invention also relates to a system of charging a flat-rate for a customer's use of a communication network and providing variable actual nominal bit rate (NBR r ) suitable for momentarily desired nominal bit rates requested by the customer. In one embodiment, a system of generating an actual Nominal Bit Rate (NBR r ) 20 to determine a priority in a SIMA network for a customer which desires a NBR d to transmit a packet of information via the network, comprises: a customer management unit, the customer management unit providing a flat-rate Nominal Bit Rate (NBR p ) for the customer, the NBR p being predefined between the customer and the network, and providing a NBR pool having a maximum pool size (S max ), the S max being predefined between the customer and the network, the NBR pool being filled by a customer's NBR p and depleted by a customer's NBR d ; and a NBR pool unit for generating the NBR r based on the NBR p , the S max and the NBR d . Still in one embodiment, the NBR pool unit determines a size of the NBR pool, wherein when the NBR pool is empty, the NBR pool unit generates the NBR r to be the NBR p ; when the size of the NBR pool is not smaller than the maximum pool size S max , the NBR pool unit generates the NBR r to be the NBR d ; when the size of the NBR pool is smaller than the maximum pool size S max but not empty, the NBR pool unit generates the NBR r to be a sum of the NBR p and a NBR pool rate; the NBR pool rate being determined by the size of the NBR pool being divided by a time interval (Δt), the time interval being a time period for the network to change the actual Nominal Bit Rate. In an alternative embodiment, instead of having a maximum pool size, the NBR pool is filled and/or emptied not proportional to NBR p , NBR d , but progressively as a function of NBR p , NBR d . In one embodiment, the NBR pool is filled either by not using the NBR p or by using a NBR r lower than the NBR p . The reserved NBR pool, upon a certain time period, can be used to serve a corresponding much higher NBR r under a certain period of time. The longer the NBR pool is filled or not used, the higher the NBR r can be used, and the longer the use of a higher NBR r can last. Accordingly, the desired NBR d is the NBR r , and the time of using this NBR r is determined based on the fact that the NBR pool does not become negative. Further in the alternative embodiment, a constant z is predefined by the network operator to determine how the NBR pool is progressively filled and/or emptied as a function of NBR. The constant z can be 0, 1, 1.5, 2, etc. When the constant z is zero, the NBR pool is filled and/or emptied proportional to NBR p , NBR r used by the customer as discussed in the first embodiment. In another embodiment, the constant z is one. Furthermore, the constant z can be implemented in the pay rate charged to the customer. Further in one embodiment, a size of the NBR pool is determined. The NBR pool is filled by using a first NBR r lower than the NBR p for a first period of time and is emptied by using a second NBR r higher than the NBR p for a second period of time. The second NBR r and the corresponding second period of time are determined by the first NBR r and the corresponding first period of time and the constant z. One advantage of the alternative embodiment is that it allows the customer to be able to use temporarily much higher NBR than what they normally use. In particular, it allows the customer to pay a low rate for a normal use of a low NBR but temporarily using a much higher NBR. These and various other advantages and features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and form a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings which form a further part hereof, and to accompanying descriptive matter, in which there are illustrated and described specific examples of an apparatus in accordance with the invention. BRIEF DESCRIPTION OF THE DRAWINGS Referring now to the drawings in which like reference numbers represent corresponding parts throughout: FIG. 1 illustrates SIMA network nodes used in communication from one customer to the other in a SIMA network in which a NBR pool unit of the present invention can be adapted. FIG. 2 is a block diagram of one embodiment of a NBR pool adapted for a SIMA network according to the present invention. FIG. 3 is a block diagram of an alternative embodiment of a NBR pool adapted for a SIMA network according to the present invention. DETAILED DESCRIPTION OF THE INVENTION In the following description of the exemplary embodiment, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration the specific embodiment in which the invention may be practiced. It is to be understood that other embodiments may be utilized as structural changes may be made without departing from the scope of the present invention. The present invention discloses a NBR pool that is used with SIMA network so that a customer of a network service provider is allowed to change his/her NBR without any actual time-dependent charging. The NBR pool method and apparatus of the present invention has both the simplicity of flat-rate charging and the flexibility of time-dependent scheme. Accordingly, the present invention provides a new approach to manage the SIMA network charging scheme using customer' NBR. In particular, a NBR pool unit controls the actual NBR used for determining the SIMA priorities based on the NBR desired by the customer, the customer's flat rate (or called “permanent”) NBR, and a maximum pool size. NBR Nominal Bit Rate (bits/s) NBR p Permanent NBR bought by a customer (based on the flat-rate paid) (bits/s) NBR d Desired NBR by the customer (during the use of the network) (bits/s) NBR r Actual NBR used during the period (bits/s) S max Maximum size of a NBR pool (bits) CE (Figure 1) Customer Equipment A (Figure 1) SIMA network access node C (Figure 1) SIMA network core node ATM Asynchronous Transfer Mode SIMA Simple Integrated Media Access PL: Priority Level Δt A time interval between the network changing the actual Nominal Bit Rate (NBR r ) (second) Period A period of time during which the NBR used by the customer (NBR r ) (second) S(0) Pool filling level at the beginning of a period (bits) S(t) Pool filling level at the end of period (bits) t Duration of the period (seconds) z Constant (e.g. 0, 1, 2, . . . etc.) In FIG. 1, a NBR pool unit or system 100 in accordance with the present invention is adapted to a SIMA (Simple Integrated Media Access) network 102 . It is appreciated that the NBR pool unit 100 can also be adapted to or equipped with other networks, such as a conventional Internet Media Access network, etc. Generally, when a customer or customer equipment (CE 1 ) sends data packets or cells of information to another customer or customer equipment (CE 2 ), customer CE 1 accesses the network at node A 1 (network access node). There are several routes, for examples, A 1 C 1 C 2 , A 1 C 1 C 4 , A 1 C 3 C 4 , to reach another network access node A 2 accessible to customer or customer equipment CE 2 . C 1 , C 2 , C 3 , C 4 are network core nodes. Accordingly, packets (frames or cells) of information are transmitted from one customer to the other customer via the network access nodes and network core nodes. FIG. 2 illustrates a block diagram of a NBR pool unit 200 for the SIMA network 102 according to the present invention. Packets of information 202 are transmitted from a customer equipment 204 to a SIMA access node 206 . An actual NBR, NBR,, for determining priority level of the packets 202 at the SIMA access node 206 , is provided by the NBR pool unit 200 . The NBR pool unit 200 is coupled to the customer management unit 208 which provides the pool unit 200 with a permanent or flat-rate NBR, NBR p , and the maximum size of the pool S max . The permanent NBR and the maximum pool size can be selected by the customer based on the fee paid to the network service provider. The NBR pool unit 200 is also coupled to the customer equipment 204 which provides the NBR pool unit 200 with the momentary NBR desired by the customer, NBR d . Based on the values of NBR p , S max , and NBR d , the NBR pool unit 200 determines the actual NBR value, NBR r . The NBR pool unit 200 has a changeable pool size (bit) which does not exceed the maximum size of pool: S max (bit). When the NBR pool service is started, the pool size is full, that is: S ( t= 0)= S max The network may change the actual bit rate NBR r , at intervals of Δt. In determining the actual bit rate NBR r , the NBR pool unit 200 operates a following method for the next interval: S(t+Δt) = S(t) − Δt · NBR d + Δt · NBR p If S(t+Δt) >= S max then NBR r = NBR d S(t+Δt) = S max else if S(t+Δt) >= 0 then NBR r = NBR d else NBR r = NBR p + S(t)/Δt S(t+Δt) = 0 Accordingly, the NBR pool is filled by rate NBR p and depleted by rate NBR d as long as there is something in the pool to be used for a desired NBR. For example, if the pool is empty, the permanent NBR p is used for the desired NBR r . If the pool has not yet reserved enough for he desired NBR d for the entire period Δt, the pool unit provides an actual NBR as being a NBR such that the pool is empty exactly at the end of the period Δt. In other words, the actual NBR can be the NBR p with additional bit rate determined by the formerly available pool size S(t) and the interval 66 t. Thereafter, the pool is empty. The time constant 66 t may be short enough for practical uses—the main issue is that most customers are satisfied. On the other hand, the time constant Δt is long enough in order to avoid very short and strong peaks of high priority traffic sent to the network, which could deteriorate the predictability SIMA network services. In one embodiment, the time constant Δt is approximately 1 minute. It is appreciated that other suitable values, such as 1.5 minutes, 10 seconds, etc., can be used without departure from the principles of the present invention. As mentioned above, the maximum pool size, S max , of the pool also has an effect on the charging scheme, for example, the monthly fee, as a very large pool for all customers makes the network dimensioning more difficult which costs more. A relatively smaller sized pool can be used for a standard service. In one embodiment, the maximum pool size, S max , is approximately 1 giga bits. It is appreciated that other suitable values can be used, such as 500 mega bits, 10 giga bits, etc., can be used without departure from the principles of the present invention. In practice, the actual determination of the parameters, Δt and S max , can be predetermined or predefined by the network operator. In NBR pool operation according to the present invention, the customer management unit 208 provides a customer's permanent or flat-rate NBC p , a maximum pool size. Based on the NBR p , S max , and the customer's momentarily desired NBR d , the NBR pool unit 200 generates an actual NBR for determining the priority level of the packets of information to be transmitted from the customer equipment 204 to SIMA access node 206 . Accordingly, the present invention allows the customer's NBR to be changed without any actual time-dependent charging. One of the advantages of a network system equipped with the NBR pool unit 200 is that a pure flat-rate charging is possible even though the customer is allowed to change the NBR. In FIG. 3, an alternative embodiment of a NBR pool 300 adapted for a SIMA network is shown. Packets of information 302 are transmitted from a customer equipment 304 to a SIMA access node 306 . An actual NBR, NBR,, for determining priority level of the packets 302 at the SIMA access node 306 , is provided by the NBR pool unit 300 . The NBR pool unit 300 is coupled to the customer management unit 308 which provides the pool unit 300 with a permanent or flat-rate NBR, NBR p , and the network constant z. The NBR p can be selected by the customer based on the fee paid to the network service provider. The constant z can be provided by the network service provider, e.g. z is 0, 1, 1.5, 2, or other suitable constant within the principles of the invention. The constant z can also be selected by a customer based on a fee paid to the network service provider. The NBR pool unit 300 is also coupled to the customer equipment 304 which provides the NBR pool unit 300 with the momentarily much higher NBR desired by the customer. Based on the values of NBR p , z, and NBR r , the NBR pool unit 300 provides the desired much higher NBR, NBR r . In the alternative embodiment, the NBR pool can be filled either by not using the NBR p or by using a NBR r lower than the NBR p . The reserved NBR pool after a certain time period can be used to serve a corresponding much higher NBR r for a certain period of time. The longer the NBR pool is filled or not used, the higher the NBR r can be used, and the longer the use of a higher NBR r can last. Accordingly, the NBR r serves the desired NBR for a period of time, and the time of serving this desired NBR is determined based on the fact that the NBR pool does not become negative. Formulae for the network to determine a pool filling level at the end of the period is as follows: S  ( t ) = S  ( 0 ) + t · ( NBR p - ( NBR r NBR p ) z  NBR r ) In addition, one criteria on which the network operates is that the network does not allow the filling level of the pool to become negative. Therefore: NBR r     can     be     at     most  :     NBR p · ( S  ( 0 ) t · NBR p + 1 ) 1 / ( 1 + z ) As shown in the formula, if z=0, the first embodiment of the present invention as discussed above is obtained, i.e. S  ( t ) = S  ( 0 ) + t · ( NBR p - ( NBR r NBR p ) z  NBR r ) If z approaches infinity, a conventional system without a NBR pool is obtained. The constant z can be any suitable number, such as 0, 1, 1.5, 2, etc. In one preferred embodiment, the constant z is set to be 1. It is appreciated that the network operator can set and/or reset the constant z without departure from the principles of the present invention. It is also appreciated that the constant z can be predefined by the network operator or predefined between the network operator and the customer. If it is supposed that NBR p is, for instance, 100 kbit/s, the customer can use the pool as presented in the following Table 1. In each case the NBR pool is empty at the beginning. Then, the customer is filling the NBR pool by setting NBR=0 for a period t(1). During the next period from t(1) to t(2), the customer is draining the NBR pool in a way that it will be empty just at the end of the period. As shown in the Table, the NBR that can be used during the second period depends strongly on the constant z. TABLE 1 NBR(1) t(1) S(1) t2-t1 NBR(2) kbit/s Case S(0) kbit/s hour Mbit min z = 0 z = 1 z = 2 (S2) 1 0 0 1/60    6  1   200  141 126 0 2 0 0  1   360  1   6100  781 394 0 3 0 0  1   360  10   700  265 191 0 4 0 0  1   360 120   150  124 114 0 5 0 0 24  8640  1  144100  3796 1129  0 6 0 0 24  8640  10  14500  1204 525 0 7 0 0 24  8640 120   1300  360 235 0 8 0 0 14*24 120960  1 2016100 14198 2721  0 9 0 0 14*24 120960  10  201700  4491 1263  0 10  0 0 14*24 120960 120  16900  1300 553 0 For instance, in case 6 using the above formula, the customer fills a NBR pool by keeping NBR zero for 24 hours such that at the end of the 24 hours, the occupancy level of the NBR pool is 8.64 Gbit: The NBR pool is filled in the first 24 hrs, and the pool level S is: S (24hrs)=0+24*3600( s )*(100−(0/100 0 *0)=8640*10(Kbit/ s )or 8640(Mbit/ s ) or 8.64(Gbit/ s ). The NBR pool can then be drained depending on what the customer's desire is. If the customer needs 10 minutes in the second period and the constant z is 0, then the NBR r at most in the second period can be: NBR r = NBR p · ( S  ( 0 ) t · NBR p + 1 ) 1 / ( 1 + z ) =    100 * ( 8640 * 10 3  ( kbit / s ) /    ( 10 * 60 * 100 ) + 1 ) 1 =    14500     ( kbit / s ) . Similarly, if the constant z is 1, the NBR r at most can be 1204 (kbit/s) for 10 minutes; if the constant z is 2, the NBR r at most can be 525 (kbit/s) for 10 minutes. Therefore, if z is 0, the customer can have as high NBR as 14.5 Mbit/s for a period of 10 minutes before the pool is empty, whereas with z=1, the corresponding NBR that the customer can have is only about 1.2 Mbit/s. From the operator's viewpoint, the first period NBR value could bring about serious difficulties as regards the network dimensioning while the latter one could be quite harmless. Note that in case when z=1, the average NBR over the periods t1 and t2 is only 8.3 kbit/s ((0*24*3600+1204*10*60)/(24*3600+10*60)=8.3 kbit/s), whereas in case when z=0, the average NBR is 100 kbit/s ((0*24*3600+14500*10*60)/(24*3600+10*60)=100 kbit/s). Further, if the NBR r of 300 kbit/s is desired by the customer for a video phone call of 10 minutes. Then, in case of z=0, the customer needs to keep NBR zero only for 20 minutes to make the call possible. The corresponding periods for cases z=1 and z=2 are 80 min. and 260 min., respectively. Finally, if the paid permanent NBR p is 100 kbit/s and the customer is using permanently only 50 kbit/s, the customer can have a NBR r of 500 kbit/s every day for 45 minutes (assume the constant z is 1. The calculation is as follows: S( 24hrs)=0+24*3600( s )*(100−(50/100) 1 *50)=75*24*3600(Kbit/ s ) NBR r = NBR p · ( S  ( 0 ) t · NBR p + 1 ) 1 / ( 1 + z ) 500 = 100 * ( ( 75 * 24 * 3600  ( kbit / s ) / ( t * 100 ) + 1 ) ) 1 / 2 t = 2700     ( s ) = 45     min . Further, similar to the first embodiment, the NBR r remains constant over a period that could be of the order of 1 minute. Accordingly, in this alternative embodiment, the emptying rate of the NBR pool is not directly the difference between NBR p and NBR r as in the first preferred embodiment, but it depends on the NBR p to NBR r ratio. In this way, it is not necessary to limit a pool size (S max ), although the customer is given an option to decide whether s/he would want to limit a pool size, i.e., either using a scheme having a maximum pool size or using a scheme without having a maximum pool size. Alternatively, the two schemes can be combined in a suitable manner which gives the customer an option to choose one of the schemes without departure from the scope of the present invention. The main advantage of the alternative embodiment as described above is that it takes automatically into account the fact that the contingent high bit rate peaks make the network dimensioning very difficult. In this scheme, the customer can momentarily have quite high NBR r but at the expense of having a much lower average NBR r . On the other hand, the main advantage of the first embodiment as described above is that it provides the customer a higher average NBR r at the expense of not having as high NBR r as the customer desires. The foregoing description of the exemplary embodiment of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not with this detailed description, but rather by the claims appended hereto.
A method and system is used in a communication network for charging a flat- rate for a customer's Nominal Bit Rate (NBR p ) of the network as well as providing a variable actual Nominal Bit Rate (NBR r ) suitable for momentarily desired high nominal bit rates requested by the customer. In one embodiment, the network provides a maximum pool size (S max ) which is predefined between a network operator and the customer. In another embodiment, instead of having the maximum pool size, the network provides the variable NBR r by filling the NBR pool progressively as a function of NBR p , a customer's desired Nominal Bit Rate (NBR d ), and a constant z, for a period of time. A momentarily much higher NBR r can be provided based on the capacity of the filled NBR pool.
Briefly describe the main idea outlined in the provided context.
[ "RELATED PATENT APPLICATION The present invention relates to U.S. patent application entitled “USE ALLOWED PRIORITY LEVEL FOR ROUTING DECISION IN SIMA NETWORKS”, Ser.", "No. 09/146,862 filed Sep. 3, 1998;", "U.S. patent application entitled “USE OF PRIORITIES DEFINED BY A CUSTOMER IN A SIMA NETWORK”, Ser.", "No. 09/159,005 filed Sep. 23, 1998;", "U.S. patent application entitled “NOMINAL BIT RATE NETWORK SERVICE”, Ser.", "No. 08/821,273, filed Mar. 20, 1997;", "U.S. patent application entitled “CELL SCHEDULING SYSTEM AND METHOD FOR NETWORK NODES”, Ser.", "No. 08/822,266, filed Mar. 20, 1997, now U.S. Pat. No. 6,081,505;", "and U.S. patent application entitled “ACCOUNTING SYSTEM AND METHOD FOR A NOMINAL BIT RATE NETWORK SERVICE”, Ser.", "No. 08/822,270, filed Mar. 20, 1997, now U.S. Pat. No. 6,047,326;", "the subject matter of which are hereby incorporated by reference.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This invention relates in general to communication systems, and more particularly, to a method and system for managing information communicated over a Simple Integrated Media Access (SIMA) network with a Nominal Bit Rate (NBR) pool.", "Description of Related Art Simple Integrated Media Access (SIMA) is a new way of introducing new properties for packet-based data networks, such as TCP/IP or ATM networks.", "The basic idea of SIMA relies on the use of eight packet-discarding priority levels, as described in details in the above-mentioned patent applications, entitled “NOMINAL BIT RATE NETWORK SERVICE”, NC 7664, Ser.", "No. 08/821,273, filed Mar.20, 1997;", "U.S. patent application entitled “CELL SCHEDULING SYSTEM AND METHOD FOR NETWORK NODES”, NC 7665, Ser.", "No. 08/822,266, filed Mar. 20, 1997;", "and U.S. patent application entitled “ACCOUNTING SYSTEM AND METHOD FOR A NOMINAL BIT RATE NETWORK SERVICE”, NC 7701, Ser.", "No. 08/822,270, filed Mar. 20, 1997;", "the subject matter of which are hereby incorporated by reference.", "Every data packet is equipped with a priority level (PL) that can be an integer between 0 and 7.", "In the latest SIMA literature, the term “priority level”", "is often replaced by “drop preference”", "which has the same meaning as “priority level.”", "In a SIMA network, priority is used for selecting packets that are discarded during congestion of a network node.", "The priority is determined from the ratio of a momentary actual bit rate of the source (a customer) to the Nominal Bit Rate (NBR) assigned to the source (the customer).", "This determination is performed in a network access node that is the first network element to receive a packet from a customer equipment.", "A conventional way of managing customer charging on Internet is based on flat- rate, that is, each customer pays a monthly fee and gets certain Internet service.", "Since the management of a more complicated charging scheme for every individual customer means excessive management and cost, the flat-rate charging scheme is currently a prevalent way.", "SIMA network with this type of simple flat-rate charging scheme is presently available for the customer.", "The monthly fee, for example $X, is translated to a certain NBR.", "The available network capacity is then divided among competing connections proportional to the NBR of each connection or customer.", "With typical data applications and low bit rate real-time applications, this SIMA network system may work properly.", "However, if a SIMA customer has, for instance, a permanent or flat-rate NBR of 50 kbit/s, and he/she desires to send a video stream with a speed of 500 kbit/s (i.e. higher NBR), the outcome could be totally unsatisfactory in using the simple flat-rate charging scheme.", "The priority of the packets (or called frames or cells) of information will be so low that the packet loss ratio will be very high.", "Consequently, the video quality will be very low for any practical purpose.", "This problem can be solved by combining the flat rate scheme and a time-dependent charging scheme presented in the above-mentioned U.S. patent applications.", "Although this solution is technically quite simple, it requires many changes in customer's management and charging.", "For example, the customer has to keep track of what period of time that he/she has requested for what NBR, other than the permanent NBR, and how much it is for such NBR, etc.", "Accordingly, there is a need in the communication industry for a network management architecture and method that can combine the simplicity of flat-rate charging and the flexibility of time-dependent scheme into a SIMA network system.", "SUMMARY OF THE INVENTION The present invention relates to communication systems, and more particularly, to a method and system for managing information communicated over a SIMA network with a Nominal Bit Rate (NBR) pool.", "To overcome the limitations in the prior art described above, and to overcome other limitations that will become apparent upon reading and understanding the present specification, the present invention discloses a NBR pool that is used with SIMA network so that a customer of a network service provider is allowed to change his/her NBR without any actual time-dependent charging.", "The NBR pool method and apparatus of the present invention has both the simplicity of flat-rate charging and the flexibility of time-dependent scheme.", "The advantage of this system is that a “pure”", "flat-rate charging is possible even though the customer is allowed to change the NBR.", "In one embodiment of the present invention, a NBR pool is established such that each SIMA customer has a permanent NBR based on the monthly fee (flat or fixed fee) or some other fee schedules, such as semi-monthly, weekly, or annual fees, etc.", "In addition, the customer is allowed to momentarily use a higher NBR, but only during a limited time period and for a limited amount.", "Further in one embodiment of the present invention, the NBR pool unit controls an actual NBR used for determining the SIMA priorities based on a NBR desired by the customer, a permanent NBR, and the maximum pool size.", "The present invention also relates to a method of charging a flat-rate for a customer's use of a communication network and providing variable actual nominal bit rate (NBR r ) to suit for momentarily desired nominal bit rates requested by the customer.", "In one embodiment, a method of generating an actual Nominal Bit Rate (NBRr r ) to determine a priority in a SIMA network for a customer which desires a NBR d to transmit a packet of information via the network, comprises: providing a flat-rate Nominal Bit Rate (NBR p ) for the customer, the NBR p being predefined between the customer and the network;", "providing a NBR pool having a maximum pool size (S max ), the S max being predefined between the customer and the network, the NBR pool being filled by a customer's NBR p and depleted by a customer's NBR d ;", "and generating the NBR r based on the NBR p , the S max , and the NBR d .", "Still in one embodiment of the present invention, the generating NBR r includes determining a size of the NBR pool, wherein when the NBR pool is empty, the NBR r is the NBR p ;", "when the size of the NBR pool is not smaller than the maximum pool size S max , the NBR r is the NBR d ;", "when the size of the NBR pool is smaller than the maximum pool size S max but not empty, the NBR r is a sum of the NBR p and a NBR pool rate;", "the NBR pool rate being determined by the size of the NBR pool being divided by a time interval (Δt), the time interval being a time period for the network to change the actual Nominal Bit Rate.", "Further in one embodiment of the present invention, the time interval is approximately one minute.", "Yet in one embodiment of the present invention, the maximum pool size is approximately one giga bits.", "The present invention also relates to a system of charging a flat-rate for a customer's use of a communication network and providing variable actual nominal bit rate (NBR r ) suitable for momentarily desired nominal bit rates requested by the customer.", "In one embodiment, a system of generating an actual Nominal Bit Rate (NBR r ) 20 to determine a priority in a SIMA network for a customer which desires a NBR d to transmit a packet of information via the network, comprises: a customer management unit, the customer management unit providing a flat-rate Nominal Bit Rate (NBR p ) for the customer, the NBR p being predefined between the customer and the network, and providing a NBR pool having a maximum pool size (S max ), the S max being predefined between the customer and the network, the NBR pool being filled by a customer's NBR p and depleted by a customer's NBR d ;", "and a NBR pool unit for generating the NBR r based on the NBR p , the S max and the NBR d .", "Still in one embodiment, the NBR pool unit determines a size of the NBR pool, wherein when the NBR pool is empty, the NBR pool unit generates the NBR r to be the NBR p ;", "when the size of the NBR pool is not smaller than the maximum pool size S max , the NBR pool unit generates the NBR r to be the NBR d ;", "when the size of the NBR pool is smaller than the maximum pool size S max but not empty, the NBR pool unit generates the NBR r to be a sum of the NBR p and a NBR pool rate;", "the NBR pool rate being determined by the size of the NBR pool being divided by a time interval (Δt), the time interval being a time period for the network to change the actual Nominal Bit Rate.", "In an alternative embodiment, instead of having a maximum pool size, the NBR pool is filled and/or emptied not proportional to NBR p , NBR d , but progressively as a function of NBR p , NBR d .", "In one embodiment, the NBR pool is filled either by not using the NBR p or by using a NBR r lower than the NBR p .", "The reserved NBR pool, upon a certain time period, can be used to serve a corresponding much higher NBR r under a certain period of time.", "The longer the NBR pool is filled or not used, the higher the NBR r can be used, and the longer the use of a higher NBR r can last.", "Accordingly, the desired NBR d is the NBR r , and the time of using this NBR r is determined based on the fact that the NBR pool does not become negative.", "Further in the alternative embodiment, a constant z is predefined by the network operator to determine how the NBR pool is progressively filled and/or emptied as a function of NBR.", "The constant z can be 0, 1, 1.5, 2, etc.", "When the constant z is zero, the NBR pool is filled and/or emptied proportional to NBR p , NBR r used by the customer as discussed in the first embodiment.", "In another embodiment, the constant z is one.", "Furthermore, the constant z can be implemented in the pay rate charged to the customer.", "Further in one embodiment, a size of the NBR pool is determined.", "The NBR pool is filled by using a first NBR r lower than the NBR p for a first period of time and is emptied by using a second NBR r higher than the NBR p for a second period of time.", "The second NBR r and the corresponding second period of time are determined by the first NBR r and the corresponding first period of time and the constant z. One advantage of the alternative embodiment is that it allows the customer to be able to use temporarily much higher NBR than what they normally use.", "In particular, it allows the customer to pay a low rate for a normal use of a low NBR but temporarily using a much higher NBR.", "These and various other advantages and features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and form a part hereof.", "However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings which form a further part hereof, and to accompanying descriptive matter, in which there are illustrated and described specific examples of an apparatus in accordance with the invention.", "BRIEF DESCRIPTION OF THE DRAWINGS Referring now to the drawings in which like reference numbers represent corresponding parts throughout: FIG. 1 illustrates SIMA network nodes used in communication from one customer to the other in a SIMA network in which a NBR pool unit of the present invention can be adapted.", "FIG. 2 is a block diagram of one embodiment of a NBR pool adapted for a SIMA network according to the present invention.", "FIG. 3 is a block diagram of an alternative embodiment of a NBR pool adapted for a SIMA network according to the present invention.", "DETAILED DESCRIPTION OF THE INVENTION In the following description of the exemplary embodiment, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration the specific embodiment in which the invention may be practiced.", "It is to be understood that other embodiments may be utilized as structural changes may be made without departing from the scope of the present invention.", "The present invention discloses a NBR pool that is used with SIMA network so that a customer of a network service provider is allowed to change his/her NBR without any actual time-dependent charging.", "The NBR pool method and apparatus of the present invention has both the simplicity of flat-rate charging and the flexibility of time-dependent scheme.", "Accordingly, the present invention provides a new approach to manage the SIMA network charging scheme using customer'", "NBR.", "In particular, a NBR pool unit controls the actual NBR used for determining the SIMA priorities based on the NBR desired by the customer, the customer's flat rate (or called “permanent”) NBR, and a maximum pool size.", "NBR Nominal Bit Rate (bits/s) NBR p Permanent NBR bought by a customer (based on the flat-rate paid) (bits/s) NBR d Desired NBR by the customer (during the use of the network) (bits/s) NBR r Actual NBR used during the period (bits/s) S max Maximum size of a NBR pool (bits) CE (Figure 1) Customer Equipment A (Figure 1) SIMA network access node C (Figure 1) SIMA network core node ATM Asynchronous Transfer Mode SIMA Simple Integrated Media Access PL: Priority Level Δt A time interval between the network changing the actual Nominal Bit Rate (NBR r ) (second) Period A period of time during which the NBR used by the customer (NBR r ) (second) S(0) Pool filling level at the beginning of a period (bits) S(t) Pool filling level at the end of period (bits) t Duration of the period (seconds) z Constant (e.g. 0, 1, 2, .", "etc.) In FIG. 1, a NBR pool unit or system 100 in accordance with the present invention is adapted to a SIMA (Simple Integrated Media Access) network 102 .", "It is appreciated that the NBR pool unit 100 can also be adapted to or equipped with other networks, such as a conventional Internet Media Access network, etc.", "Generally, when a customer or customer equipment (CE 1 ) sends data packets or cells of information to another customer or customer equipment (CE 2 ), customer CE 1 accesses the network at node A 1 (network access node).", "There are several routes, for examples, A 1 C 1 C 2 , A 1 C 1 C 4 , A 1 C 3 C 4 , to reach another network access node A 2 accessible to customer or customer equipment CE 2 .", "C 1 , C 2 , C 3 , C 4 are network core nodes.", "Accordingly, packets (frames or cells) of information are transmitted from one customer to the other customer via the network access nodes and network core nodes.", "FIG. 2 illustrates a block diagram of a NBR pool unit 200 for the SIMA network 102 according to the present invention.", "Packets of information 202 are transmitted from a customer equipment 204 to a SIMA access node 206 .", "An actual NBR, NBR,, for determining priority level of the packets 202 at the SIMA access node 206 , is provided by the NBR pool unit 200 .", "The NBR pool unit 200 is coupled to the customer management unit 208 which provides the pool unit 200 with a permanent or flat-rate NBR, NBR p , and the maximum size of the pool S max .", "The permanent NBR and the maximum pool size can be selected by the customer based on the fee paid to the network service provider.", "The NBR pool unit 200 is also coupled to the customer equipment 204 which provides the NBR pool unit 200 with the momentary NBR desired by the customer, NBR d .", "Based on the values of NBR p , S max , and NBR d , the NBR pool unit 200 determines the actual NBR value, NBR r .", "The NBR pool unit 200 has a changeable pool size (bit) which does not exceed the maximum size of pool: S max (bit).", "When the NBR pool service is started, the pool size is full, that is: S ( t= 0)= S max The network may change the actual bit rate NBR r , at intervals of Δt.", "In determining the actual bit rate NBR r , the NBR pool unit 200 operates a following method for the next interval: S(t+Δt) = S(t) − Δt · NBR d + Δt · NBR p If S(t+Δt) >= S max then NBR r = NBR d S(t+Δt) = S max else if S(t+Δt) >= 0 then NBR r = NBR d else NBR r = NBR p + S(t)/Δt S(t+Δt) = 0 Accordingly, the NBR pool is filled by rate NBR p and depleted by rate NBR d as long as there is something in the pool to be used for a desired NBR.", "For example, if the pool is empty, the permanent NBR p is used for the desired NBR r .", "If the pool has not yet reserved enough for he desired NBR d for the entire period Δt, the pool unit provides an actual NBR as being a NBR such that the pool is empty exactly at the end of the period Δt.", "In other words, the actual NBR can be the NBR p with additional bit rate determined by the formerly available pool size S(t) and the interval 66 t. Thereafter, the pool is empty.", "The time constant 66 t may be short enough for practical uses—the main issue is that most customers are satisfied.", "On the other hand, the time constant Δt is long enough in order to avoid very short and strong peaks of high priority traffic sent to the network, which could deteriorate the predictability SIMA network services.", "In one embodiment, the time constant Δt is approximately 1 minute.", "It is appreciated that other suitable values, such as 1.5 minutes, 10 seconds, etc.", ", can be used without departure from the principles of the present invention.", "As mentioned above, the maximum pool size, S max , of the pool also has an effect on the charging scheme, for example, the monthly fee, as a very large pool for all customers makes the network dimensioning more difficult which costs more.", "A relatively smaller sized pool can be used for a standard service.", "In one embodiment, the maximum pool size, S max , is approximately 1 giga bits.", "It is appreciated that other suitable values can be used, such as 500 mega bits, 10 giga bits, etc.", ", can be used without departure from the principles of the present invention.", "In practice, the actual determination of the parameters, Δt and S max , can be predetermined or predefined by the network operator.", "In NBR pool operation according to the present invention, the customer management unit 208 provides a customer's permanent or flat-rate NBC p , a maximum pool size.", "Based on the NBR p , S max , and the customer's momentarily desired NBR d , the NBR pool unit 200 generates an actual NBR for determining the priority level of the packets of information to be transmitted from the customer equipment 204 to SIMA access node 206 .", "Accordingly, the present invention allows the customer's NBR to be changed without any actual time-dependent charging.", "One of the advantages of a network system equipped with the NBR pool unit 200 is that a pure flat-rate charging is possible even though the customer is allowed to change the NBR.", "In FIG. 3, an alternative embodiment of a NBR pool 300 adapted for a SIMA network is shown.", "Packets of information 302 are transmitted from a customer equipment 304 to a SIMA access node 306 .", "An actual NBR, NBR,, for determining priority level of the packets 302 at the SIMA access node 306 , is provided by the NBR pool unit 300 .", "The NBR pool unit 300 is coupled to the customer management unit 308 which provides the pool unit 300 with a permanent or flat-rate NBR, NBR p , and the network constant z. The NBR p can be selected by the customer based on the fee paid to the network service provider.", "The constant z can be provided by the network service provider, e.g. z is 0, 1, 1.5, 2, or other suitable constant within the principles of the invention.", "The constant z can also be selected by a customer based on a fee paid to the network service provider.", "The NBR pool unit 300 is also coupled to the customer equipment 304 which provides the NBR pool unit 300 with the momentarily much higher NBR desired by the customer.", "Based on the values of NBR p , z, and NBR r , the NBR pool unit 300 provides the desired much higher NBR, NBR r .", "In the alternative embodiment, the NBR pool can be filled either by not using the NBR p or by using a NBR r lower than the NBR p .", "The reserved NBR pool after a certain time period can be used to serve a corresponding much higher NBR r for a certain period of time.", "The longer the NBR pool is filled or not used, the higher the NBR r can be used, and the longer the use of a higher NBR r can last.", "Accordingly, the NBR r serves the desired NBR for a period of time, and the time of serving this desired NBR is determined based on the fact that the NBR pool does not become negative.", "Formulae for the network to determine a pool filling level at the end of the period is as follows: S  ( t ) = S  ( 0 ) + t · ( NBR p - ( NBR r NBR p ) z  NBR r ) In addition, one criteria on which the network operates is that the network does not allow the filling level of the pool to become negative.", "Therefore: NBR r   can   be   at   most  :   NBR p · ( S  ( 0 ) t · NBR p + 1 ) 1 / ( 1 + z ) As shown in the formula, if z=0, the first embodiment of the present invention as discussed above is obtained, i.e. S  ( t ) = S  ( 0 ) + t · ( NBR p - ( NBR r NBR p ) z  NBR r ) If z approaches infinity, a conventional system without a NBR pool is obtained.", "The constant z can be any suitable number, such as 0, 1, 1.5, 2, etc.", "In one preferred embodiment, the constant z is set to be 1.", "It is appreciated that the network operator can set and/or reset the constant z without departure from the principles of the present invention.", "It is also appreciated that the constant z can be predefined by the network operator or predefined between the network operator and the customer.", "If it is supposed that NBR p is, for instance, 100 kbit/s, the customer can use the pool as presented in the following Table 1.", "In each case the NBR pool is empty at the beginning.", "Then, the customer is filling the NBR pool by setting NBR=0 for a period t(1).", "During the next period from t(1) to t(2), the customer is draining the NBR pool in a way that it will be empty just at the end of the period.", "As shown in the Table, the NBR that can be used during the second period depends strongly on the constant z. TABLE 1 NBR(1) t(1) S(1) t2-t1 NBR(2) kbit/s Case S(0) kbit/s hour Mbit min z = 0 z = 1 z = 2 (S2) 1 0 0 1/60 6 1 200 141 126 0 2 0 0 1 360 1 6100 781 394 0 3 0 0 1 360 10 700 265 191 0 4 0 0 1 360 120 150 124 114 0 5 0 0 24 8640 1 144100 3796 1129 0 6 0 0 24 8640 10 14500 1204 525 0 7 0 0 24 8640 120 1300 360 235 0 8 0 0 14*24 120960 1 2016100 14198 2721 0 9 0 0 14*24 120960 10 201700 4491 1263 0 10 0 0 14*24 120960 120 16900 1300 553 0 For instance, in case 6 using the above formula, the customer fills a NBR pool by keeping NBR zero for 24 hours such that at the end of the 24 hours, the occupancy level of the NBR pool is 8.64 Gbit: The NBR pool is filled in the first 24 hrs, and the pool level S is: S (24hrs)=0+24*3600( s )*(100−(0/100 0 *0)=8640*10(Kbit/ s )or 8640(Mbit/ s ) or 8.64(Gbit/ s ).", "The NBR pool can then be drained depending on what the customer's desire is.", "If the customer needs 10 minutes in the second period and the constant z is 0, then the NBR r at most in the second period can be: NBR r = NBR p · ( S  ( 0 ) t · NBR p + 1 ) 1 / ( 1 + z ) =  100 * ( 8640 * 10 3  ( kbit / s ) /  ( 10 * 60 * 100 ) + 1 ) 1 =  14500   ( kbit / s ) .", "Similarly, if the constant z is 1, the NBR r at most can be 1204 (kbit/s) for 10 minutes;", "if the constant z is 2, the NBR r at most can be 525 (kbit/s) for 10 minutes.", "Therefore, if z is 0, the customer can have as high NBR as 14.5 Mbit/s for a period of 10 minutes before the pool is empty, whereas with z=1, the corresponding NBR that the customer can have is only about 1.2 Mbit/s.", "From the operator's viewpoint, the first period NBR value could bring about serious difficulties as regards the network dimensioning while the latter one could be quite harmless.", "Note that in case when z=1, the average NBR over the periods t1 and t2 is only 8.3 kbit/s ((0*24*3600+1204*10*60)/(24*3600+10*60)=8.3 kbit/s), whereas in case when z=0, the average NBR is 100 kbit/s ((0*24*3600+14500*10*60)/(24*3600+10*60)=100 kbit/s).", "Further, if the NBR r of 300 kbit/s is desired by the customer for a video phone call of 10 minutes.", "Then, in case of z=0, the customer needs to keep NBR zero only for 20 minutes to make the call possible.", "The corresponding periods for cases z=1 and z=2 are 80 min.", "and 260 min.", ", respectively.", "Finally, if the paid permanent NBR p is 100 kbit/s and the customer is using permanently only 50 kbit/s, the customer can have a NBR r of 500 kbit/s every day for 45 minutes (assume the constant z is 1.", "The calculation is as follows: S( 24hrs)=0+24*3600( s )*(100−(50/100) 1 *50)=75*24*3600(Kbit/ s ) NBR r = NBR p · ( S  ( 0 ) t · NBR p + 1 ) 1 / ( 1 + z ) 500 = 100 * ( ( 75 * 24 * 3600  ( kbit / s ) / ( t * 100 ) + 1 ) ) 1 / 2 t = 2700   ( s ) = 45   min .", "Further, similar to the first embodiment, the NBR r remains constant over a period that could be of the order of 1 minute.", "Accordingly, in this alternative embodiment, the emptying rate of the NBR pool is not directly the difference between NBR p and NBR r as in the first preferred embodiment, but it depends on the NBR p to NBR r ratio.", "In this way, it is not necessary to limit a pool size (S max ), although the customer is given an option to decide whether s/he would want to limit a pool size, i.e., either using a scheme having a maximum pool size or using a scheme without having a maximum pool size.", "Alternatively, the two schemes can be combined in a suitable manner which gives the customer an option to choose one of the schemes without departure from the scope of the present invention.", "The main advantage of the alternative embodiment as described above is that it takes automatically into account the fact that the contingent high bit rate peaks make the network dimensioning very difficult.", "In this scheme, the customer can momentarily have quite high NBR r but at the expense of having a much lower average NBR r .", "On the other hand, the main advantage of the first embodiment as described above is that it provides the customer a higher average NBR r at the expense of not having as high NBR r as the customer desires.", "The foregoing description of the exemplary embodiment of the invention has been presented for the purposes of illustration and description.", "It is not intended to be exhaustive or to limit the invention to the precise form disclosed.", "Many modifications and variations are possible in light of the above teaching.", "It is intended that the scope of the invention be limited not with this detailed description, but rather by the claims appended hereto." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 201210505402.8 filed in China, P.R.C. on Nov. 30, 2012, the entire contents of which are hereby incorporated by reference. BACKGROUND OF THE DISCLOSURE [0002] 1. Technical Field of the Disclosure [0003] The disclosure relates to a printed circuit board (PCB), and more particularly to a PCB capable of performing wireless transmission and a server using the same. [0004] 2. Description of the Related Art [0005] In the manufacturing of a PCB, circuit layout is generally performed first to generate an electronic file of a layout chart. That is, a layout engineer places electronic components at predetermined positions on the PCB, connects the electronic components with wires to complete the design of the layout chart, and proceed to Gerber out according to the electronic file of the layout chart to generate a mask picture. Finally, the PCB manufacturer manufactures the PCB through the mask picture. [0006] FIG. 1 is a block diagram of an ordinary PCB. To implement a signal transmission and related operations between the components, the layout engineer needs to perform wiring of components 110 , 120 , 130 , 140 on the PCB 100 by using wires, so as to connect the components 110 , 120 , 130 , 140 . In the layout of the PCB 100 , since the distances between the components 110 , 120 , 130 , 140 are not the same, the layout engineer needs to set the wires of the same length between the components 110 , 120 , 130 , 140 , to achieve a time sequence synchronization of signals. Additionally, since diversified components are disposed on the PCB 100 and the space is limited, when the component 110 needs to be moved, the layout engineer needs to modify the length of the wires, which takes more time for modification. [0007] The above layout manner may increase the design complexity of the layout, prolong the layout time, lower the layout efficiency, and waste the utilization space of the PCB. Therefore, the design of the PCB needs to be improved. SUMMARY OF THE DISCLOSURE [0008] In an embodiment, the disclosure provides a printed circuit board (PCB) comprising a plurality of receiving components and a sending component. Each of the receiving components comprises a receiving unit and a first control unit. The receiving unit is configured for receiving a radio signal. The first control unit is coupled to the receiving unit and is configured with a first comparison table storing related information of the receiving component. The first control unit is configured for decoding the radio signal according to the first comparison table, so as to obtain a corresponding control signal. The sending component comprises a sending unit and a second control unit. The sending unit is configured for sending the radio signals. The second control unit is coupled to the sending unit and is configured with a second comparison table storing the related information of the receiving components. When the sending component outputs the control signals through the second control unit, the second control unit generates the control signals according to the related information of the receiving components, and encodes the control signals to generate the radio signals. BRIEF DESCRIPTION OF THE DRAWINGS [0009] The disclosure will become more fully understood from the detailed description given herein below for illustration only, thus does not limit the disclosure, wherein: [0010] FIG. 1 is a block diagram of an ordinary PCB; [0011] FIG. 2A is a block diagram of a PCB of the disclosure; [0012] FIG. 2B is another block diagram of a PCB of the disclosure; [0013] FIG. 3A is a block diagram of a server of the disclosure; and [0014] FIG. 3B is another block diagram of a server of the disclosure. DETAILED DESCRIPTION [0015] In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing. [0016] In the following embodiments, the same or similar components are marked by the same symbols. [0017] FIG. 2A is a block diagram of a PCB of the disclosure. The PCB 200 in this embodiment is a mainboard of a server. The PCB 200 comprises receiving components 210 , 220 , 230 and a sending component 240 . [0018] For ease of description, three receiving components (that is, the receiving components 210 , 220 , 230 ) are used in this embodiment as an example for illustration, but the disclosure is not limited thereto. Moreover, the user may adjust the number of the receiving components to be three or more upon requirements. The receiving components 210 , 220 , 230 are, for example, central processing units (CPUs), hard disks or other circuit components, such as resistors, inductors or capacitors. [0019] The receiving components 210 , 220 , 230 respectively have receiving units 211 , 221 , 231 and first control units 212 , 222 , 232 . The receiving units 211 , 221 , 231 are used for receiving radio signals. [0020] The first control units 212 , 222 , 232 are coupled to the receiving units 211 , 221 , 231 , and are respectively configured with a first comparison table, the first comparison tables respectively storing related information of the receiving components 210 , 220 , 230 . The first control units 212 , 222 , 232 receive the radio signals, and decode the radio signals according to the related information of the receiving components 210 , 220 , 230 in the first comparison tables, to obtain corresponding control signals and proceed to perform related operations. [0021] The sending component 240 comprises a sending unit 241 and a second control unit 242 . The sending unit 241 is used for sending the radio signals. The second control unit 242 is coupled to the sending unit 241 and configured with a second comparison table storing the related information of the receiving components 210 , 220 , 230 . When the sending component 240 is used for outputting the control signals through the second control unit 242 , the second control unit 242 generates the corresponding control signals according to the related information of the receiving components 210 , 220 , 230 . The second control unit 242 further encodes the control signals to generate the corresponding radio signals to be sent by the sending unit 241 . [0022] In this embodiment, the related information of the receiving components 210 , 220 , 230 comprises names and part numbers of the receiving components 210 , 220 , 230 . The first comparison table of the first control unit 212 stores the name and the part number of the receiving component 210 . The first comparison table of the first control unit 222 stores the name and the part number of the receiving component 220 . The first comparison table of the first control unit 232 stores the name and the part number of the receiving component 230 . The second comparison table of the second control unit 242 stores the names and the part numbers of the receiving components 210 , 220 , 230 . [0023] Since the second control unit 242 is capable of acquiring the corresponding part numbers and names of the receiving components 210 , 220 , 230 by looking up the second comparison table, the second control unit 242 generates the control signals, adds the names and the part numbers of the receiving components 210 , 220 , 230 into the corresponding control signals, and encodes the control signals into the radio signals to be sent by the sending unit 241 to the receiving components 210 , 220 , 230 . [0024] For example, assume that the name of the receiving component 210 is “resistor” and the part number thereof is “R 1 ”, the name of the receiving component 220 is “inductor” and the part number thereof is “L 2 ”, and the name of the receiving component 230 is “CPU” and the part number thereof is “CPU 3 ”. The second control unit 242 , for example, adds the serial number of “resistor_R 1 ” into the control signal to be transmitted to the receiving component 210 , the second control unit 242 , for example, adds the serial number of “inductor_L 2 ” into the control signal to be transmitted to the receiving component 220 , and the second control unit 242 , for example, adds the serial number of “CPU_CPU 3 ” into the control signal to be transmitted to the receiving component 230 . [0025] When the receiving component 210 receives the radio signal having the serial number of “resistor_R 1 ” through the receiving unit 211 , the first control unit 212 decodes the radio signal having the serial number of “resistor_R 1 ”, to obtain the control signal having the serial number of “resistor_R 1 ”. The first control unit 212 , subsequently is configured for confirming that the serial number of “resistor_R 1 ” is consistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is transmitted to the receiving component 210 . Therefore, the receiving component 210 performs related operations according to the control signal. [0026] When the receiving component 210 receives the radio signal having the serial number of “inductor_L 2 ” through the receiving unit 211 , the first control unit 212 decodes the radio signal having the serial number of “inductor_L 2 ”, to obtain the control signal having the serial number of “inductor_L 2 ”. The first control unit 212 , subsequently, is configured for confirming that the serial number of “inductor_L 2 ” is inconsistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 210 . Therefore, the receiving component 210 does not perform related operations. [0027] When the receiving component 210 receives the radio signal having the serial number of “CPU_CPU 3 ” through the receiving unit 211 , the first control unit 212 decodes the radio signal having the serial number of “CPU_CPU 3 ”, to obtain the control signal having the serial number of “CPU_CPU 3 ”. Then, the first control unit 212 is configured for confirming that the serial number of “CPU_CPU 3 ” is inconsistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 210 . Therefore, the receiving component 210 does not perform related operations. [0028] Reference can be made to the implementation and description of the receiving component 210 for the related operations of the receiving components 220 , 230 , and the details are not repeated herein. The receiving components 210 , 220 , 230 respectively decode the received radio signals to obtain the control signals transmitted thereto, so as to perform related operations. Therefore, signal transmission errors can be avoided, and the wiring between the sending component 240 and the receiving components 210 , 220 , 230 is saved, so that the design and layout complexity of the PCB 200 is reduced. [0029] In an embodiment, assume that the receiving components 220 and 230 are of the same type. For instance, the names of the receiving components 220 and 230 are “resistor” and the part numbers thereof are respectively “R 1 ” and “R 2 ”. The second control unit 242 , for example, adds the serial numbers of “resistor_R 1 ” and “resistor_R 2 ” into the control signals to be transmitted to the receiving components 220 and 230 , encodes the two control signals into two corresponding radio signals, and sets the radio signals into a group of radio signals to be sent by the sending unit 241 . Therefore, the sending unit 241 is capable of sending the control signals to the receiving components 220 and 230 at the same time, to achieve time sequence control of time synchronization of the signals. [0030] FIG. 2B is another block diagram of a PCB of the disclosure. The PCB 201 in this embodiment is different from the PCB 200 in FIG. 2A in that, in addition to the receiving units 211 , 221 , 231 and the first control units 212 , 222 , 232 , the receiving components 210 , 220 , 230 of the PCB 201 further comprises subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 . [0031] The first control units 212 , 222 , 232 respectively store related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 . The related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 , for example, comprises names and part numbers of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 . [0032] The second comparison table of the second control unit 242 further stores the related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 . When the sending component 240 is used for outputting the control signals through the second control unit 242 , the second control unit 242 generates the control signals according to the related information of the receiving components 210 , 220 , 230 and the related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 . [0033] Then, the second control unit 242 further sets the control signals corresponding to the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 of the receiving components 210 , 220 , 230 into a group of signals respectively, and encodes the groups of signals to generate the corresponding radio signals to be sent by the sending unit 241 to the first control units 212 , 222 , 232 of the receiving components 210 , 220 , 230 . [0034] The first control units 212 , 222 , 232 decode the radio signals having the groups of signals according to the related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 , to obtain the control signals corresponding to the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 . Thereby, the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 may perform related operations according to the corresponding control signals. [0035] For example, assume that the name of the receiving component 210 is “functional component (FC)” and the part number thereof is “FC 1 ”, the name of the subsidiary receiving component 213 is “resistor” and the part number thereof is “R 2 ”, and the name of the subsidiary receiving component 214 is “baseboard management controller (BMC)” and the part number thereof is “BMC 1 ”. The second control unit 242 , for example, adds the serial numbers of “FC_FC 1 ” and “resistor R 2 ” as well as “FC_FC 1 ” and “BMC_BMC 1 ” into the control signals to be transmitted to the subsidiary receiving components 213 , 214 of the receiving component 210 respectively. [0036] The second control unit further sets the control signals to be transmitted to the subsidiary receiving components 213 , 214 into a group of signals, and encodes the group of signals into the radio signals to be sent by the sending unit 241 . The group of signals comprises the serial numbers of “FC_FC 1 ” and “resistor_R 2 ” as well as “FC_FC 1 ” and “BMC_BMC 1 ”. [0037] When the receiving component 210 receives the radio signals having the serial numbers of “FC_FC 1 ” and “resistor_R 2 ” as well as “FC_FC 1 ” and “BMC_BMC 1 ” through the receiving unit 211 , the first control unit 212 decodes the radio signals having the serial numbers of “FC_FC 1 ” and “resistor_R 2 ” as well as “FC_FC 1 ” and “BMC_BMC 1 ”, to obtain the control signals having the serial numbers of “FC_FC 1 ” and “resistor_R 2 ” as well as “FC_FC 1 ” and “BMC_BMC 1 ”. [0038] The first control unit 212 is configured for confirming that the serial numbers of “FC_FC 1 ” and “resistor_R 2 ” as well as “FC_FC 1 ” and “BMC_BMC 1 ” are consistent with the related information (that is, the names and the part numbers) of the receiving component 210 and the subsidiary receiving components 213 , 214 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signals are transmitted to the receiving component 210 . The first control unit 212 transmits the corresponding “resistor_R 2 ” and “BMC_BMC 1 ” respectively to the subsidiary receiving components 213 , 214 , so that the subsidiary receiving components 213 , 214 perform related operations accordingly. [0039] When the first control unit 212 confirms, through comparison, that the decoded control signals are inconsistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, it is determined that the control signals are not transmitted to the receiving component 210 . Therefore, the receiving component 210 and the subsidiary receiving components 213 , 214 do not perform related operations. [0040] Reference can be made to the implementation and description of the receiving component 210 and the subsidiary receiving components 213 , 214 for the related operations of the receiving components 220 , 230 and the subsidiary receiving components 223 , 224 , 233 , 234 , and the details are not repeated herein. The receiving components 210 , 220 , 230 and the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 respectively decode the received radio signals to obtain the control signals transmitted thereto, so as to perform related operations. [0041] Therefore, signal transmission errors can be avoided, and the wiring between the sending component 240 and the receiving components 210 , 220 , 230 is saved, so that the design and layout complexity of the PCB 201 is reduced. Further, the control signals to be sent to the subsidiary receiving components of the same receiving component are set into a group of signals, so as to be sent to the receiving component at the same time. Therefore, the subsidiary receiving components are capable of receiving the control signals at the same time and performing related operations accordingly, to achieve time sequence control of time synchronization of the signals. [0042] FIG. 3A is a block diagram of a server of the disclosure. The server 300 comprises PCBs 302 and 304 . In this embodiment, the PCBs 302 and 304 in this embodiment are mainboards or riser cards of the server 300 . [0043] For ease of description, two PCBs (that is, the PCBs 302 and 304 ) are used in this embodiment as an example for illustration, but the disclosure is not limited thereto. Therefore, the user may adjust the number of the PCBs to be two or more upon requirements. [0044] In this embodiment, the PCB 302 comprises receiving components 310 , 320 , 330 and a sending component 340 . The receiving components 310 , 320 , 330 respectively comprise receiving units 311 , 321 , 331 and first control units 312 , 322 , 332 . The sending component 340 comprises a sending unit 341 and a second control unit 342 . [0045] The PCB 304 comprises receiving components 350 , 360 , 370 and a sending component 380 . The receiving components 350 , 360 , 370 respectively comprise receiving units 351 , 361 , 371 and first control units 352 , 362 , 372 . The sending component 380 comprises a sending unit 381 and a second control unit 382 . Reference can be made to the implementation of the PCB 200 in FIG. 2A for the internal components and implementation of the PCBs 302 and 304 , and the details are not repeated herein. [0046] The PCBs 302 and 304 in this embodiment are different from the PCB 200 in FIG. 2A in that, in addition to the related information of all the receiving components 310 , 320 , 330 , 350 , 360 , 370 , the second comparison tables in the second control units 342 and 382 of the PCBs 302 and 304 further store the related information of the PCBs 302 and 304 . [0047] Therefore, when the sending components 340 , 380 are used for outputting the control signals through the second control units 342 , 382 , the second control units 342 , 382 generate the corresponding control signals according to the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the related information of the PCBs 302 , 304 , and further encode the control signals to generate the corresponding radio signals to be sent by the sending units 341 , 381 . [0048] In addition to the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 , the first comparison tables in the first control units 312 , 322 , 332 , 352 , 362 , 372 of the PCBs 302 and 304 further store the related information of the PCBs 302 , 304 . That is, the first comparison table in the first control unit 312 stores the related information of the receiving component 310 and the related information of the corresponding PCB 302 . The implementation of the remaining first control units 322 , 332 , 352 , 362 , 372 can be deduced by analogy. [0049] In this embodiment, the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 comprises the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 . The first comparison tables in the first control units 312 , 322 , 332 , 352 , 362 , 372 of the receiving components 310 , 320 , 330 , 350 , 360 , 370 respectively store the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 . [0050] The related information of the PCBs 302 and 304 , for example, comprises the names and the part numbers of the PCBs 302 and 304 . The second comparison tables in the second control units 342 and 382 respectively store the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the names and the part numbers of the PCBs 302 and 304 . [0051] The second control units 342 and 382 acquire, by looking up the second comparison tables, the corresponding part numbers and names of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the PCBs 302 , 304 , so that the second control units 342 and 382 generate the control signals, add the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the PCBs 302 , 304 into the corresponding control signals, and encode the control signals into the radio signals to be sent by the sending units 341 and 381 to the receiving components 310 , 320 , 330 , 350 , 360 , 370 . [0052] For example, assume that the name of the receiving component 310 is “resistor” and the part number thereof is “R 1 ”, the name of the receiving component 320 is “inductor” and the part number thereof is “L 2 ”, the name of the receiving component 330 is “CPU” and the part number thereof is “CPU 3 ”, the name of the receiving component 350 is “resistor” and the part number thereof is “R 2 ”, the name of the receiving component 360 is “inductor” and the part number thereof is “L 4 ”, the name of the receiving component 370 is “capacitor” and the part number thereof is “C 3 ”, the name of the PCB 302 is “PCB 1 ” and the part number thereof is “ 001 ”, and the name of the PCB 304 is “PCB 2 ” and the part number thereof is “ 003 ”. [0053] The second control unit 342 , for example, adds the serial numbers of “resistor_R 1 ” and “PCB 1 _ 001 ” into the control signal to be transmitted to the receiving component 310 , the second control unit 342 , for example, adds the serial numbers of “inductor_L 2 ” and “PCB 1 _ 001 ” into the control signal to be transmitted to the receiving component 320 , the second control unit 342 , for example, adds the serial numbers of “CPU_CPU 3 ” and “PCB 1 _ 001 ” into the control signal to be transmitted to the receiving component 330 , the second control unit 342 , for example, adds the serial numbers of “resistor_R 2 ” and “PCB 2 _ 003 ” into the control signal to be transmitted to the receiving component 350 , the second control unit 342 , for example, adds the serial numbers of “inductor_L 4 ” and “PCB 2 _ 003 ” into the control signal to be transmitted to the receiving component 360 , and the second control unit 342 , for example, adds the serial numbers of “capacitor_C 3 ” and “PCB 2 _ 003 ” into the control signal to be transmitted to the receiving component 370 . The implementation of the second control unit 382 can be deduced by analogy, and the details are not repeated herein. [0054] When the receiving component 310 receives the radio signal having the serial numbers of “resistor_R 1 ” and “PCB 1 _ 001 ” through the receiving unit 311 , the first control unit 312 decodes the radio signal having the serial numbers of “resistor_R 1 ” and “PCB 1 _ 001 ”, to obtain the control signal having the serial numbers of “resistor_R 1 ” and “PCB 1 _ 001 ”. Then, The first control unit 312 is configured for confirming that the serial numbers of “resistor_R 1 ” and “PCB 1 _ 001 ” are consistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is transmitted to the receiving component 310 . Therefore, the receiving component 310 performs related operations according to the control signal. [0055] When the receiving component 310 receives the radio signal having the serial numbers of “inductor_L 2 ” and “PCB 1 _ 001 ” through the receiving unit 311 , the first control unit 312 decodes the radio signal having the serial numbers of “inductor_L 2 ” and “PCB 1 _ 001 ”, to obtain the control signal having the serial numbers of “inductor_L 2 ” and “PCB 1 _ 001 ”. Then, the first control unit 312 is configured for confirming that the serial numbers of “inductor_L 2 ” and “PCB 1 _ 001 ” are inconsistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 310 . Therefore, the receiving component 310 does not perform related operations. [0056] When the receiving component 310 receives the radio signal having the serial numbers of “CPU_CPU 3 ” and “PCB 1 _ 001 ” through the receiving unit 311 , the first control unit 212 decodes the radio signal having the serial numbers of “CPU_CPU 3 ” and “PCB 1 _ 001 ”, to obtain the control signal having the serial numbers of “CPU_CPU 3 ” and “PCB 1 _ 001 ”, and is configured for confirming that the serial numbers of “CPU_CPU 3 ” and “PCB 1 _ 001 ” are inconsistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 310 . Therefore, the receiving component 310 does not perform related operations. [0057] When the receiving component 310 receives the radio signal having the serial numbers of “resistor_R 2 ” and “PCB 2 _ 003 ” through the receiving unit 311 , the first control unit 212 decodes the radio signal having the serial numbers of “resistor_R 2 ” and “PCB 2 _ 003 ”, to obtain the control signal having the serial numbers of “resistor_R 2 ” and “PCB 2 _ 003 ”, and is configured for confirming that the serial numbers of “resistor_R 2 ” and “PCB 2 _ 003 ” are inconsistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 310 . Therefore, the receiving component 310 does not perform related operations. The rest can be deduced by analogy. [0058] Reference can be made to the implementation and description of the receiving component 310 for the related operations of the receiving components 320 , 330 , 350 , 360 , 370 , and the details are not repeated herein. The receiving components 320 , 330 , 350 , 360 , 370 are configured for respectively decoding the received radio signals to obtain the control signals transmitted thereto, so as to perform related operations. Therefore, signal transmission errors can be avoided, and the wiring between the sending components 340 , 380 and the receiving components 310 , 320 , 330 , 350 , 360 , 370 is saved. Thereby, the design and layout complexity of the PCBs 302 , 304 in the server 300 is reduced. [0059] In an embodiment, assume that the receiving components 320 and 330 are of the same type. For example, the names of the receiving components 320 and 330 are “resistor” and the part numbers thereof are respectively “R 1 ” and “R 2 ”. The second control unit 342 , for example, adds the serial numbers of “resistor_R 1 ” and “resistor_R 2 ” into the control signals to be transmitted to the receiving components 320 and 330 , encodes the two control signals into two corresponding radio signals, and sets the radio signals into a group of radio signals to be sent by the sending unit 341 . Therefore, the sending unit 341 is capable of sending the control signals to the receiving components 320 and 330 at the same time, to achieve time sequence control of time synchronization of the signals. [0060] FIG. 3B is another block diagram of a server of the disclosure. The PCBs 303 and 305 of the server 301 in this embodiment are different from the PCBs 302 , 304 in FIG. 3A in that, in addition to the receiving units 311 , 321 , 331 , 351 , 361 , 371 and the first control units 312 , 322 , 332 , 352 , 362 , 372 , the receiving components 310 , 320 , 330 , 350 , 360 , 370 of the PCBs 302 , 304 further comprise subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 . [0061] The first control units 312 , 322 , 332 , 352 , 362 , 372 respectively store related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 . The related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 , for example, comprises names and part numbers of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 . [0062] The second comparison tables in the second control units 342 and 382 further store the related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 . When the sending components 340 and 380 are used for outputting the control signals through the second control units 342 and 382 , the second control units 342 and 382 generate the control signals according to the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 . [0063] The second control units 342 and 382 further set the control signals corresponding to the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 of the receiving components 310 , 320 , 330 , 350 , 360 , 370 into a group of signals respectively, and encode the groups of signals to generate the corresponding radio signals to be sent by the sending units 341 and 381 to the first control units 311 , 321 , 331 , 351 , 361 , 371 of the receiving components 310 , 320 , 330 , 350 , 360 , 370 . [0064] Then, the first control units 311 , 321 , 331 , 351 , 361 , 371 decode the radio signals having the groups of signals according to the related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 , to obtain the control signals corresponding to the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 . Thereby, the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 may perform related operations according to the corresponding control signals. [0065] Reference can be made to the implementation of the PCB 201 in FIG. 2B for the implementation of the PCBs 302 , 304 , and the details are not repeated herein. Therefore, this embodiment is able to reduce the design and layout complexity of the PCBs 302 , 304 , to achieve time sequence control of time sequence synchronization of the signals. [0066] According to the PCB and the server using the same provided by the embodiments of the disclosure, the sending component is configured with the sending unit and the receiving components are configured with the receiving units, and the second control unit generates the control signals to be output to the receiving components according to the related information of the receiving components, encodes the control signals to generate the radio signals, and transmits the radio signals to the receiving units in a wireless manner. The receiving units decode the radio signals, and the first control units of the receiving units obtain the corresponding control signals according to the related information of the receiving components, so as to perform related operations. [0067] In addition to the related information of the receiving components, the second control unit may also generate the corresponding control signals according to the related information of the PCBs. Thereby, false actions of the receiving components on different PCBs can be prevented. When the receiving components are of the same type, the second control unit encodes the control signals into the radio signals, and sets the radio signals into a group of radio signals to be sent by the sending unit. Furthermore, the control signals to be sent to the subsidiary receiving components of the same receiving component are set into a group of signals, so that the subsidiary receiving components are capable of receiving the control signals at the same time and performing related operations accordingly. Therefore, the design complexity of the layout is effectively reduced, the layout efficiency and utilization space of the PCB are improved, and time sequence control of time synchronization of the signals is achieved.
A printed circuit board (PCB) includes multiple receiving components and a sending component. Each receiving component includes a receiving unit and a first control unit. The receiving unit receives a radio signal. The first control unit is configured with a first comparison table storing related information of the receiving component, and used for decoding the radio signal according to the first comparison table, to obtain a corresponding control signal. The sending component includes a sending unit and a second control unit. The sending unit sends the radio signals. The second control unit is configured with a second comparison table storing the related information of the receiving components. When the sending component outputs the control signals through the second control unit, the second control unit generates the control signals according to the second comparison table, and encodes the control signals to generate the radio signals.
Identify the most important claim in the given context and summarize it
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s).", "201210505402.8 filed in China, P.R.C. on Nov. 30, 2012, the entire contents of which are hereby incorporated by reference.", "BACKGROUND OF THE DISCLOSURE [0002] 1.", "Technical Field of the Disclosure [0003] The disclosure relates to a printed circuit board (PCB), and more particularly to a PCB capable of performing wireless transmission and a server using the same.", "[0004] 2.", "Description of the Related Art [0005] In the manufacturing of a PCB, circuit layout is generally performed first to generate an electronic file of a layout chart.", "That is, a layout engineer places electronic components at predetermined positions on the PCB, connects the electronic components with wires to complete the design of the layout chart, and proceed to Gerber out according to the electronic file of the layout chart to generate a mask picture.", "Finally, the PCB manufacturer manufactures the PCB through the mask picture.", "[0006] FIG. 1 is a block diagram of an ordinary PCB.", "To implement a signal transmission and related operations between the components, the layout engineer needs to perform wiring of components 110 , 120 , 130 , 140 on the PCB 100 by using wires, so as to connect the components 110 , 120 , 130 , 140 .", "In the layout of the PCB 100 , since the distances between the components 110 , 120 , 130 , 140 are not the same, the layout engineer needs to set the wires of the same length between the components 110 , 120 , 130 , 140 , to achieve a time sequence synchronization of signals.", "Additionally, since diversified components are disposed on the PCB 100 and the space is limited, when the component 110 needs to be moved, the layout engineer needs to modify the length of the wires, which takes more time for modification.", "[0007] The above layout manner may increase the design complexity of the layout, prolong the layout time, lower the layout efficiency, and waste the utilization space of the PCB.", "Therefore, the design of the PCB needs to be improved.", "SUMMARY OF THE DISCLOSURE [0008] In an embodiment, the disclosure provides a printed circuit board (PCB) comprising a plurality of receiving components and a sending component.", "Each of the receiving components comprises a receiving unit and a first control unit.", "The receiving unit is configured for receiving a radio signal.", "The first control unit is coupled to the receiving unit and is configured with a first comparison table storing related information of the receiving component.", "The first control unit is configured for decoding the radio signal according to the first comparison table, so as to obtain a corresponding control signal.", "The sending component comprises a sending unit and a second control unit.", "The sending unit is configured for sending the radio signals.", "The second control unit is coupled to the sending unit and is configured with a second comparison table storing the related information of the receiving components.", "When the sending component outputs the control signals through the second control unit, the second control unit generates the control signals according to the related information of the receiving components, and encodes the control signals to generate the radio signals.", "BRIEF DESCRIPTION OF THE DRAWINGS [0009] The disclosure will become more fully understood from the detailed description given herein below for illustration only, thus does not limit the disclosure, wherein: [0010] FIG. 1 is a block diagram of an ordinary PCB;", "[0011] FIG. 2A is a block diagram of a PCB of the disclosure;", "[0012] FIG. 2B is another block diagram of a PCB of the disclosure;", "[0013] FIG. 3A is a block diagram of a server of the disclosure;", "and [0014] FIG. 3B is another block diagram of a server of the disclosure.", "DETAILED DESCRIPTION [0015] In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments.", "It will be apparent, however, that one or more embodiments may be practiced without these specific details.", "In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.", "[0016] In the following embodiments, the same or similar components are marked by the same symbols.", "[0017] FIG. 2A is a block diagram of a PCB of the disclosure.", "The PCB 200 in this embodiment is a mainboard of a server.", "The PCB 200 comprises receiving components 210 , 220 , 230 and a sending component 240 .", "[0018] For ease of description, three receiving components (that is, the receiving components 210 , 220 , 230 ) are used in this embodiment as an example for illustration, but the disclosure is not limited thereto.", "Moreover, the user may adjust the number of the receiving components to be three or more upon requirements.", "The receiving components 210 , 220 , 230 are, for example, central processing units (CPUs), hard disks or other circuit components, such as resistors, inductors or capacitors.", "[0019] The receiving components 210 , 220 , 230 respectively have receiving units 211 , 221 , 231 and first control units 212 , 222 , 232 .", "The receiving units 211 , 221 , 231 are used for receiving radio signals.", "[0020] The first control units 212 , 222 , 232 are coupled to the receiving units 211 , 221 , 231 , and are respectively configured with a first comparison table, the first comparison tables respectively storing related information of the receiving components 210 , 220 , 230 .", "The first control units 212 , 222 , 232 receive the radio signals, and decode the radio signals according to the related information of the receiving components 210 , 220 , 230 in the first comparison tables, to obtain corresponding control signals and proceed to perform related operations.", "[0021] The sending component 240 comprises a sending unit 241 and a second control unit 242 .", "The sending unit 241 is used for sending the radio signals.", "The second control unit 242 is coupled to the sending unit 241 and configured with a second comparison table storing the related information of the receiving components 210 , 220 , 230 .", "When the sending component 240 is used for outputting the control signals through the second control unit 242 , the second control unit 242 generates the corresponding control signals according to the related information of the receiving components 210 , 220 , 230 .", "The second control unit 242 further encodes the control signals to generate the corresponding radio signals to be sent by the sending unit 241 .", "[0022] In this embodiment, the related information of the receiving components 210 , 220 , 230 comprises names and part numbers of the receiving components 210 , 220 , 230 .", "The first comparison table of the first control unit 212 stores the name and the part number of the receiving component 210 .", "The first comparison table of the first control unit 222 stores the name and the part number of the receiving component 220 .", "The first comparison table of the first control unit 232 stores the name and the part number of the receiving component 230 .", "The second comparison table of the second control unit 242 stores the names and the part numbers of the receiving components 210 , 220 , 230 .", "[0023] Since the second control unit 242 is capable of acquiring the corresponding part numbers and names of the receiving components 210 , 220 , 230 by looking up the second comparison table, the second control unit 242 generates the control signals, adds the names and the part numbers of the receiving components 210 , 220 , 230 into the corresponding control signals, and encodes the control signals into the radio signals to be sent by the sending unit 241 to the receiving components 210 , 220 , 230 .", "[0024] For example, assume that the name of the receiving component 210 is “resistor”", "and the part number thereof is “R 1 ”, the name of the receiving component 220 is “inductor”", "and the part number thereof is “L 2 ”, and the name of the receiving component 230 is “CPU”", "and the part number thereof is “CPU 3 .”", "The second control unit 242 , for example, adds the serial number of “resistor_R 1 ”", "into the control signal to be transmitted to the receiving component 210 , the second control unit 242 , for example, adds the serial number of “inductor_L 2 ”", "into the control signal to be transmitted to the receiving component 220 , and the second control unit 242 , for example, adds the serial number of “CPU_CPU 3 ”", "into the control signal to be transmitted to the receiving component 230 .", "[0025] When the receiving component 210 receives the radio signal having the serial number of “resistor_R 1 ”", "through the receiving unit 211 , the first control unit 212 decodes the radio signal having the serial number of “resistor_R 1 ”, to obtain the control signal having the serial number of “resistor_R 1 .”", "The first control unit 212 , subsequently is configured for confirming that the serial number of “resistor_R 1 ”", "is consistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is transmitted to the receiving component 210 .", "Therefore, the receiving component 210 performs related operations according to the control signal.", "[0026] When the receiving component 210 receives the radio signal having the serial number of “inductor_L 2 ”", "through the receiving unit 211 , the first control unit 212 decodes the radio signal having the serial number of “inductor_L 2 ”, to obtain the control signal having the serial number of “inductor_L 2 .”", "The first control unit 212 , subsequently, is configured for confirming that the serial number of “inductor_L 2 ”", "is inconsistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 210 .", "Therefore, the receiving component 210 does not perform related operations.", "[0027] When the receiving component 210 receives the radio signal having the serial number of “CPU_CPU 3 ”", "through the receiving unit 211 , the first control unit 212 decodes the radio signal having the serial number of “CPU_CPU 3 ”, to obtain the control signal having the serial number of “CPU_CPU 3 .”", "Then, the first control unit 212 is configured for confirming that the serial number of “CPU_CPU 3 ”", "is inconsistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 210 .", "Therefore, the receiving component 210 does not perform related operations.", "[0028] Reference can be made to the implementation and description of the receiving component 210 for the related operations of the receiving components 220 , 230 , and the details are not repeated herein.", "The receiving components 210 , 220 , 230 respectively decode the received radio signals to obtain the control signals transmitted thereto, so as to perform related operations.", "Therefore, signal transmission errors can be avoided, and the wiring between the sending component 240 and the receiving components 210 , 220 , 230 is saved, so that the design and layout complexity of the PCB 200 is reduced.", "[0029] In an embodiment, assume that the receiving components 220 and 230 are of the same type.", "For instance, the names of the receiving components 220 and 230 are “resistor”", "and the part numbers thereof are respectively “R 1 ”", "and “R 2 .”", "The second control unit 242 , for example, adds the serial numbers of “resistor_R 1 ”", "and “resistor_R 2 ”", "into the control signals to be transmitted to the receiving components 220 and 230 , encodes the two control signals into two corresponding radio signals, and sets the radio signals into a group of radio signals to be sent by the sending unit 241 .", "Therefore, the sending unit 241 is capable of sending the control signals to the receiving components 220 and 230 at the same time, to achieve time sequence control of time synchronization of the signals.", "[0030] FIG. 2B is another block diagram of a PCB of the disclosure.", "The PCB 201 in this embodiment is different from the PCB 200 in FIG. 2A in that, in addition to the receiving units 211 , 221 , 231 and the first control units 212 , 222 , 232 , the receiving components 210 , 220 , 230 of the PCB 201 further comprises subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 .", "[0031] The first control units 212 , 222 , 232 respectively store related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 .", "The related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 , for example, comprises names and part numbers of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 .", "[0032] The second comparison table of the second control unit 242 further stores the related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 .", "When the sending component 240 is used for outputting the control signals through the second control unit 242 , the second control unit 242 generates the control signals according to the related information of the receiving components 210 , 220 , 230 and the related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 .", "[0033] Then, the second control unit 242 further sets the control signals corresponding to the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 of the receiving components 210 , 220 , 230 into a group of signals respectively, and encodes the groups of signals to generate the corresponding radio signals to be sent by the sending unit 241 to the first control units 212 , 222 , 232 of the receiving components 210 , 220 , 230 .", "[0034] The first control units 212 , 222 , 232 decode the radio signals having the groups of signals according to the related information of the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 , to obtain the control signals corresponding to the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 .", "Thereby, the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 may perform related operations according to the corresponding control signals.", "[0035] For example, assume that the name of the receiving component 210 is “functional component (FC)”", "and the part number thereof is “FC 1 ”, the name of the subsidiary receiving component 213 is “resistor”", "and the part number thereof is “R 2 ”, and the name of the subsidiary receiving component 214 is “baseboard management controller (BMC)”", "and the part number thereof is “BMC 1 .”", "The second control unit 242 , for example, adds the serial numbers of “FC_FC 1 ”", "and “resistor R 2 ”", "as well as “FC_FC 1 ”", "and “BMC_BMC 1 ”", "into the control signals to be transmitted to the subsidiary receiving components 213 , 214 of the receiving component 210 respectively.", "[0036] The second control unit further sets the control signals to be transmitted to the subsidiary receiving components 213 , 214 into a group of signals, and encodes the group of signals into the radio signals to be sent by the sending unit 241 .", "The group of signals comprises the serial numbers of “FC_FC 1 ”", "and “resistor_R 2 ”", "as well as “FC_FC 1 ”", "and “BMC_BMC 1 .”", "[0037] When the receiving component 210 receives the radio signals having the serial numbers of “FC_FC 1 ”", "and “resistor_R 2 ”", "as well as “FC_FC 1 ”", "and “BMC_BMC 1 ”", "through the receiving unit 211 , the first control unit 212 decodes the radio signals having the serial numbers of “FC_FC 1 ”", "and “resistor_R 2 ”", "as well as “FC_FC 1 ”", "and “BMC_BMC 1 ”, to obtain the control signals having the serial numbers of “FC_FC 1 ”", "and “resistor_R 2 ”", "as well as “FC_FC 1 ”", "and “BMC_BMC 1 .”", "[0038] The first control unit 212 is configured for confirming that the serial numbers of “FC_FC 1 ”", "and “resistor_R 2 ”", "as well as “FC_FC 1 ”", "and “BMC_BMC 1 ”", "are consistent with the related information (that is, the names and the part numbers) of the receiving component 210 and the subsidiary receiving components 213 , 214 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signals are transmitted to the receiving component 210 .", "The first control unit 212 transmits the corresponding “resistor_R 2 ”", "and “BMC_BMC 1 ”", "respectively to the subsidiary receiving components 213 , 214 , so that the subsidiary receiving components 213 , 214 perform related operations accordingly.", "[0039] When the first control unit 212 confirms, through comparison, that the decoded control signals are inconsistent with the related information (that is, the name and the part number) of the receiving component 210 that is stored in the first comparison table, it is determined that the control signals are not transmitted to the receiving component 210 .", "Therefore, the receiving component 210 and the subsidiary receiving components 213 , 214 do not perform related operations.", "[0040] Reference can be made to the implementation and description of the receiving component 210 and the subsidiary receiving components 213 , 214 for the related operations of the receiving components 220 , 230 and the subsidiary receiving components 223 , 224 , 233 , 234 , and the details are not repeated herein.", "The receiving components 210 , 220 , 230 and the subsidiary receiving components 213 , 214 , 223 , 224 , 233 , 234 respectively decode the received radio signals to obtain the control signals transmitted thereto, so as to perform related operations.", "[0041] Therefore, signal transmission errors can be avoided, and the wiring between the sending component 240 and the receiving components 210 , 220 , 230 is saved, so that the design and layout complexity of the PCB 201 is reduced.", "Further, the control signals to be sent to the subsidiary receiving components of the same receiving component are set into a group of signals, so as to be sent to the receiving component at the same time.", "Therefore, the subsidiary receiving components are capable of receiving the control signals at the same time and performing related operations accordingly, to achieve time sequence control of time synchronization of the signals.", "[0042] FIG. 3A is a block diagram of a server of the disclosure.", "The server 300 comprises PCBs 302 and 304 .", "In this embodiment, the PCBs 302 and 304 in this embodiment are mainboards or riser cards of the server 300 .", "[0043] For ease of description, two PCBs (that is, the PCBs 302 and 304 ) are used in this embodiment as an example for illustration, but the disclosure is not limited thereto.", "Therefore, the user may adjust the number of the PCBs to be two or more upon requirements.", "[0044] In this embodiment, the PCB 302 comprises receiving components 310 , 320 , 330 and a sending component 340 .", "The receiving components 310 , 320 , 330 respectively comprise receiving units 311 , 321 , 331 and first control units 312 , 322 , 332 .", "The sending component 340 comprises a sending unit 341 and a second control unit 342 .", "[0045] The PCB 304 comprises receiving components 350 , 360 , 370 and a sending component 380 .", "The receiving components 350 , 360 , 370 respectively comprise receiving units 351 , 361 , 371 and first control units 352 , 362 , 372 .", "The sending component 380 comprises a sending unit 381 and a second control unit 382 .", "Reference can be made to the implementation of the PCB 200 in FIG. 2A for the internal components and implementation of the PCBs 302 and 304 , and the details are not repeated herein.", "[0046] The PCBs 302 and 304 in this embodiment are different from the PCB 200 in FIG. 2A in that, in addition to the related information of all the receiving components 310 , 320 , 330 , 350 , 360 , 370 , the second comparison tables in the second control units 342 and 382 of the PCBs 302 and 304 further store the related information of the PCBs 302 and 304 .", "[0047] Therefore, when the sending components 340 , 380 are used for outputting the control signals through the second control units 342 , 382 , the second control units 342 , 382 generate the corresponding control signals according to the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the related information of the PCBs 302 , 304 , and further encode the control signals to generate the corresponding radio signals to be sent by the sending units 341 , 381 .", "[0048] In addition to the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 , the first comparison tables in the first control units 312 , 322 , 332 , 352 , 362 , 372 of the PCBs 302 and 304 further store the related information of the PCBs 302 , 304 .", "That is, the first comparison table in the first control unit 312 stores the related information of the receiving component 310 and the related information of the corresponding PCB 302 .", "The implementation of the remaining first control units 322 , 332 , 352 , 362 , 372 can be deduced by analogy.", "[0049] In this embodiment, the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 comprises the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 .", "The first comparison tables in the first control units 312 , 322 , 332 , 352 , 362 , 372 of the receiving components 310 , 320 , 330 , 350 , 360 , 370 respectively store the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 .", "[0050] The related information of the PCBs 302 and 304 , for example, comprises the names and the part numbers of the PCBs 302 and 304 .", "The second comparison tables in the second control units 342 and 382 respectively store the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the names and the part numbers of the PCBs 302 and 304 .", "[0051] The second control units 342 and 382 acquire, by looking up the second comparison tables, the corresponding part numbers and names of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the PCBs 302 , 304 , so that the second control units 342 and 382 generate the control signals, add the names and the part numbers of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the PCBs 302 , 304 into the corresponding control signals, and encode the control signals into the radio signals to be sent by the sending units 341 and 381 to the receiving components 310 , 320 , 330 , 350 , 360 , 370 .", "[0052] For example, assume that the name of the receiving component 310 is “resistor”", "and the part number thereof is “R 1 ”, the name of the receiving component 320 is “inductor”", "and the part number thereof is “L 2 ”, the name of the receiving component 330 is “CPU”", "and the part number thereof is “CPU 3 ”, the name of the receiving component 350 is “resistor”", "and the part number thereof is “R 2 ”, the name of the receiving component 360 is “inductor”", "and the part number thereof is “L 4 ”, the name of the receiving component 370 is “capacitor”", "and the part number thereof is “C 3 ”, the name of the PCB 302 is “PCB 1 ”", "and the part number thereof is “ 001 ”, and the name of the PCB 304 is “PCB 2 ”", "and the part number thereof is “ 003 .”", "[0053] The second control unit 342 , for example, adds the serial numbers of “resistor_R 1 ”", "and “PCB 1 _ 001 ”", "into the control signal to be transmitted to the receiving component 310 , the second control unit 342 , for example, adds the serial numbers of “inductor_L 2 ”", "and “PCB 1 _ 001 ”", "into the control signal to be transmitted to the receiving component 320 , the second control unit 342 , for example, adds the serial numbers of “CPU_CPU 3 ”", "and “PCB 1 _ 001 ”", "into the control signal to be transmitted to the receiving component 330 , the second control unit 342 , for example, adds the serial numbers of “resistor_R 2 ”", "and “PCB 2 _ 003 ”", "into the control signal to be transmitted to the receiving component 350 , the second control unit 342 , for example, adds the serial numbers of “inductor_L 4 ”", "and “PCB 2 _ 003 ”", "into the control signal to be transmitted to the receiving component 360 , and the second control unit 342 , for example, adds the serial numbers of “capacitor_C 3 ”", "and “PCB 2 _ 003 ”", "into the control signal to be transmitted to the receiving component 370 .", "The implementation of the second control unit 382 can be deduced by analogy, and the details are not repeated herein.", "[0054] When the receiving component 310 receives the radio signal having the serial numbers of “resistor_R 1 ”", "and “PCB 1 _ 001 ”", "through the receiving unit 311 , the first control unit 312 decodes the radio signal having the serial numbers of “resistor_R 1 ”", "and “PCB 1 _ 001 ”, to obtain the control signal having the serial numbers of “resistor_R 1 ”", "and “PCB 1 _ 001 .”", "Then, The first control unit 312 is configured for confirming that the serial numbers of “resistor_R 1 ”", "and “PCB 1 _ 001 ”", "are consistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is transmitted to the receiving component 310 .", "Therefore, the receiving component 310 performs related operations according to the control signal.", "[0055] When the receiving component 310 receives the radio signal having the serial numbers of “inductor_L 2 ”", "and “PCB 1 _ 001 ”", "through the receiving unit 311 , the first control unit 312 decodes the radio signal having the serial numbers of “inductor_L 2 ”", "and “PCB 1 _ 001 ”, to obtain the control signal having the serial numbers of “inductor_L 2 ”", "and “PCB 1 _ 001 .”", "Then, the first control unit 312 is configured for confirming that the serial numbers of “inductor_L 2 ”", "and “PCB 1 _ 001 ”", "are inconsistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 310 .", "Therefore, the receiving component 310 does not perform related operations.", "[0056] When the receiving component 310 receives the radio signal having the serial numbers of “CPU_CPU 3 ”", "and “PCB 1 _ 001 ”", "through the receiving unit 311 , the first control unit 212 decodes the radio signal having the serial numbers of “CPU_CPU 3 ”", "and “PCB 1 _ 001 ”, to obtain the control signal having the serial numbers of “CPU_CPU 3 ”", "and “PCB 1 _ 001 ”, and is configured for confirming that the serial numbers of “CPU_CPU 3 ”", "and “PCB 1 _ 001 ”", "are inconsistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 310 .", "Therefore, the receiving component 310 does not perform related operations.", "[0057] When the receiving component 310 receives the radio signal having the serial numbers of “resistor_R 2 ”", "and “PCB 2 _ 003 ”", "through the receiving unit 311 , the first control unit 212 decodes the radio signal having the serial numbers of “resistor_R 2 ”", "and “PCB 2 _ 003 ”, to obtain the control signal having the serial numbers of “resistor_R 2 ”", "and “PCB 2 _ 003 ”, and is configured for confirming that the serial numbers of “resistor_R 2 ”", "and “PCB 2 _ 003 ”", "are inconsistent with the related information (that is, the name and the part number) of the receiving component 310 that is stored in the first comparison table, by looking up the first comparison table, so as to determine that the control signal is not transmitted to the receiving component 310 .", "Therefore, the receiving component 310 does not perform related operations.", "The rest can be deduced by analogy.", "[0058] Reference can be made to the implementation and description of the receiving component 310 for the related operations of the receiving components 320 , 330 , 350 , 360 , 370 , and the details are not repeated herein.", "The receiving components 320 , 330 , 350 , 360 , 370 are configured for respectively decoding the received radio signals to obtain the control signals transmitted thereto, so as to perform related operations.", "Therefore, signal transmission errors can be avoided, and the wiring between the sending components 340 , 380 and the receiving components 310 , 320 , 330 , 350 , 360 , 370 is saved.", "Thereby, the design and layout complexity of the PCBs 302 , 304 in the server 300 is reduced.", "[0059] In an embodiment, assume that the receiving components 320 and 330 are of the same type.", "For example, the names of the receiving components 320 and 330 are “resistor”", "and the part numbers thereof are respectively “R 1 ”", "and “R 2 .”", "The second control unit 342 , for example, adds the serial numbers of “resistor_R 1 ”", "and “resistor_R 2 ”", "into the control signals to be transmitted to the receiving components 320 and 330 , encodes the two control signals into two corresponding radio signals, and sets the radio signals into a group of radio signals to be sent by the sending unit 341 .", "Therefore, the sending unit 341 is capable of sending the control signals to the receiving components 320 and 330 at the same time, to achieve time sequence control of time synchronization of the signals.", "[0060] FIG. 3B is another block diagram of a server of the disclosure.", "The PCBs 303 and 305 of the server 301 in this embodiment are different from the PCBs 302 , 304 in FIG. 3A in that, in addition to the receiving units 311 , 321 , 331 , 351 , 361 , 371 and the first control units 312 , 322 , 332 , 352 , 362 , 372 , the receiving components 310 , 320 , 330 , 350 , 360 , 370 of the PCBs 302 , 304 further comprise subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 .", "[0061] The first control units 312 , 322 , 332 , 352 , 362 , 372 respectively store related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 .", "The related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 , for example, comprises names and part numbers of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 .", "[0062] The second comparison tables in the second control units 342 and 382 further store the related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 .", "When the sending components 340 and 380 are used for outputting the control signals through the second control units 342 and 382 , the second control units 342 and 382 generate the control signals according to the related information of the receiving components 310 , 320 , 330 , 350 , 360 , 370 and the related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 .", "[0063] The second control units 342 and 382 further set the control signals corresponding to the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 of the receiving components 310 , 320 , 330 , 350 , 360 , 370 into a group of signals respectively, and encode the groups of signals to generate the corresponding radio signals to be sent by the sending units 341 and 381 to the first control units 311 , 321 , 331 , 351 , 361 , 371 of the receiving components 310 , 320 , 330 , 350 , 360 , 370 .", "[0064] Then, the first control units 311 , 321 , 331 , 351 , 361 , 371 decode the radio signals having the groups of signals according to the related information of the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 , to obtain the control signals corresponding to the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 .", "Thereby, the subsidiary receiving components 313 , 314 , 323 , 324 , 333 , 334 , 353 , 354 , 363 , 364 , 373 , 374 may perform related operations according to the corresponding control signals.", "[0065] Reference can be made to the implementation of the PCB 201 in FIG. 2B for the implementation of the PCBs 302 , 304 , and the details are not repeated herein.", "Therefore, this embodiment is able to reduce the design and layout complexity of the PCBs 302 , 304 , to achieve time sequence control of time sequence synchronization of the signals.", "[0066] According to the PCB and the server using the same provided by the embodiments of the disclosure, the sending component is configured with the sending unit and the receiving components are configured with the receiving units, and the second control unit generates the control signals to be output to the receiving components according to the related information of the receiving components, encodes the control signals to generate the radio signals, and transmits the radio signals to the receiving units in a wireless manner.", "The receiving units decode the radio signals, and the first control units of the receiving units obtain the corresponding control signals according to the related information of the receiving components, so as to perform related operations.", "[0067] In addition to the related information of the receiving components, the second control unit may also generate the corresponding control signals according to the related information of the PCBs.", "Thereby, false actions of the receiving components on different PCBs can be prevented.", "When the receiving components are of the same type, the second control unit encodes the control signals into the radio signals, and sets the radio signals into a group of radio signals to be sent by the sending unit.", "Furthermore, the control signals to be sent to the subsidiary receiving components of the same receiving component are set into a group of signals, so that the subsidiary receiving components are capable of receiving the control signals at the same time and performing related operations accordingly.", "Therefore, the design complexity of the layout is effectively reduced, the layout efficiency and utilization space of the PCB are improved, and time sequence control of time synchronization of the signals is achieved." ]
[0001] This application is a continuation of application Ser. No. 10/695,299, filed on Oct. 27, 2003, which claims the benefit of U.S. Provisional Application No. 60/423,026, filed on Nov. 1, 2002, the full disclosures of which are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates generally to medical apparatus and methods. More particularly, the present invention relates to methods and systems for facilitating, accelerating, and stabilizing tooth movement before, during and after orthodontic procedures. [0004] Orthodontic procedures suffer from four major problems. First, the braces or other appliances which effect the tooth movement must be worn for long periods of time. Second, even after a successful orthodontic treatment, the teeth often relapse towards their original positions once the braces or other treatment appliances are removed. Third, the mechanically induced movement of teeth can cause significant discomfort to the patient. Fourth, the wearing of braces is esthetically displeasing, uncomfortable, and compromises oral hygiene. While recently introduced clear plastic visible “aligners” largely overcome the latter problems, such aligners are not suitable for all patients. Moreover, the aligners do not reduce treatment time, do not reduce the risk of relapse, and do not lessen the pain associated with tooth movement in the jaw. [0005] For these reasons, it would be desirable to provide improved orthodontic technologies for moving teeth which overcome at least some of the problems noted above. In particular, it would be desirable to provide orthodontic methods and systems which can reduce the time necessary to effect a desired tooth movement, which can reduce the pain associated with tooth movement, which can reduce the tendency of teeth to relapse to their original positions after the orthodontic treatment is stopped, and/or which can reduce the time in which unsightly braces need to be worn. [0006] 2. Description of Background Art [0007] Nicozisis et al. (2000) Clin. Orthod. Res. 3:192-201, describes experiments which demonstrate the presence of endogenous relaxin in cranial tissue of mice and speculates that relaxin may be used as an adjunct to orthodontic or surgical therapy to promote manipulation of sutural tissues or affect stability. The application of electrical current to stimulate bone growth and remodeling in orthodontic procedures is described in U.S. Pat. Nos. 4,854,865; 4,519,779; and 4,153,060. Appliances for local and systematic drug delivery to the gingival tissues are described in U.S. Pat. Nos. 6,159,498, 5,633,000; 5,616,315; 5,575,655; 5,447,725; 5,294,004; 4,959,220; 4,933,183; 4,892,736; 4,685,883; and Re. 34,656. Polymeric shell appliances for repositioning teeth are described in U.S. Pat. No. 5,975,893. The full disclosures of each of the above U.S. patents are incorporated herein by reference. BRIEF SUMMARY OF THE INVENTION [0008] The present invention provides improved methods and systems for repositioning teeth in patients. In addition, the present invention provides improved methods and systems for stabilizing teeth which have already been repositioned in order to reduce or eliminate the tendency of the repositioned teeth to relapse, i.e., move back toward their prior positions. The methods for repositioning teeth comprise applying force to at least one tooth, and typically to more than one tooth and/or to different teeth over time, in the jaw of the patient. For both repositioning or stabilizing, tissue remodeling and/or an angiogenic substance(s) is administered to the patient to promote remodeling of periodontal tissue surrounding the root(s) of the tooth or teeth to be moved. Preferred substance(s) will bind to and activate the relaxin receptor in the tissues which anchor the teeth or other craniofacial structures. Most preferred is relaxin or an analog or mimetic thereof which combines tissue remodeling activity with angiogenic activity. Analogs include peptides, oligomers, fragments, etc. which comprise the active region of native relaxin and mimetics include small molecule drugs, typically below 2 kD, designed to mimic the activity of native relaxin. Alternatively, substance(s) with predominantly angiogenic activity could be selected, such as VEGF, bFGF, estrogen, nitrous oxide, naltrexone, or the like. Further alternatively, collagenases or other tissue-softening enzymes could be utilized to promote periodontal tissue remodeling according to the present invention. In some instances, it may be desirable to combine two or more tissue remodeling and/or angiogenic substance(s) having differing activities. In other instances it may be desirable to deliver different tissue remodeling and/or angiogenic substance(s) at different times during the orthodontic treatment and/or to different regions of the periodontal tissue. [0009] The term “relaxin” means human relaxin, including intact full length relaxin or a portion of the relaxin molecule that retains biological activity [as described in U.S. Pat. No. 5,023,321, preferably recombinant human relaxin (H2)] and other active agents with relaxin-like activity, such as Relaxin and portions that retain biological activity Like Factor (as described in U.S. Pat. No. 5,911,997 at SEQ ID NOS: 3 and 4, and column 5, line 27-column 6, line 4), relaxin analogs and portions that retain biological activity (as described in U.S. Pat. No. 5,811,395 at SEQ ID NOS: 1 and 2, and column 3, lines 16-40), and agents that competitively displace bound relaxin from a receptor. Relaxin can be made by any method known to those skilled in the art, for example, as described in any of U.S. Pat. Nos. 5,759,807; 4,835,251 and co-pending U.S. Ser. No. 07/908,766 (PCT US90/02085) and Ser. No. 08/080,354 (PCT US94/0699). [0010] The tissue remodeling and/or angiogenic substance(s) will be delivered at a delivery rate and a total dosage which are selected to facilitate tooth repositioning and tissue remodeling. Typically, the dosage rates will be in the range from 1 ng to 500 μg per day, usually from 10 ng/day to 20 μg/day, preferably from 20 ng/day to 10 μg/day. The dosage and other aspects of the delivery may be adjusted from time-to-time in response to the effectiveness of treatment, such as the resistance of a particular tooth or group of teeth, where the dosage might be increased if resistance is not sufficiently reduced in response to an initial dosage. [0011] The substance(s) may be delivered at any point during the orthodontic treatment where tooth repositioning and/or tissue remodeling may be promoted. For example, the substance(s) may be applied prior to any application of force intended to move the teeth. Additionally or alternatively, the substance(s) may be applied during all or any portion of the time during which force is being applied to move the teeth. Further additionally or alternatively, the substance(s) may be applied after the teeth have been repositioned to a final desired configuration. In the latter case, application of the substance(s) may be particularly effective for promoting tissue remodeling in order to reduce the risk of relapse. In such instances, the substance(s) may be delivered using retainers or other appliances intended to help maintain the teeth in their desired final configuration. When being delivered to inhibit relapse, the remodeling and/or angiogenic substance(s) may be delivered for a limited period of time in a limited period before and/or immediately following the end of the orthodontic procedure or may be delivered continuously or periodically for long periods of time or indefinitely following the end of the orthodontic procedure. For example, the substance(s) may be delivered to some or preferably all of the regions of the gingiva where teeth have been moved in order to promote stabilization and remodeling of the tissue, usually over a period of one to eight weeks, more usually two to six weeks prior to the end of treatment. [0012] The teeth may be repositioned by any conventional orthodontic appliance intended for applying force to move teeth. In particular, the present invention is compatible with both the use of wire and bracket systems, commonly referred to as “braces,” as well as with newer systems employing removable appliances for repositioning teeth, such as the Invisalign® System, available from Align Technology, Inc., Santa Clara, Calif., and the “red, white, and blue” system available from Sybron Dental Specialties, Irvine, Calif. The present invention will also be useful with dental “positioners” which are elastomeric appliances having pre-formed tooth-receiving cavities where the patient bites into the elastomeric appliance in order to force tooth movement. Finally, the present invention may be used with dental retainers which are polymeric shell appliances typically used to maintain a final, desired tooth configuration and prevent relapse. When used with dental repositioning appliances of any type, the application of the tissue remodeling and/or angiogenic substance(s) according to the present invention will usually both facilitate tooth movement by modifying the tissue structures within the periodontal tissue which anchor the teeth and also promoting tissue remodeling which allows such tissue structures to accommodate the repositioned teeth with less tendency toward relapse. [0013] The substance(s) of the present invention may be applied and administered in a wide variety of ways. Most simply, and as presently preferred, the substance(s) could be “painted” or otherwise topically applied to the patient's gingiva using a conventional single-use applicator such as a swab, brush, syringe, or the like. The substance(s) may be prepared in a conventional form of topical composition, such as a gel, cream, ointment, or other fluid or liquid substance. Alternatively, the substance(s) could be administered by injecting into the periodontal tissue. Additionally, the substance(s) could be delivered using a patch or other appliance which is worn on the teeth or gingiva, optionally being formed as part of the same appliance which is used to move the teeth, e.g., a bracket or removable shell appliance or retainer. In such instances, the substance(s) may be incorporated into conventional drug reservoirs which both maintain a supply of the substance(s) and which release the substance(s) at a controlled rate, over time, to target sites on the gingiva. Suitable drug delivery structures for delivering the substance(s) to the patient gingiva are described in the patent and medical literature, see, e.g., U.S. Pat. Nos. 6,159,498, 5,575,655; 5,194,003; 4,933,182; and 4,685,883, the full disclosures of which are incorporated herein by reference. [0014] In some instances, it may be desirable to provide for enhanced penetration of the substance(s) into the gingival. For example, the substance(s) could be formulated with tissue penetration or permeation enhancers, such as dimethylsulfoxide (DMSO). Alternatively or additionally, the substance(s) can be delivered while applying energy in a manner to promote tissue penetration, including the application of an electric current in order to achieve electroporation or iontophoresis, and/or the application of ultrasound energy. The currents needed to provide for electroporation are relatively low, typically around 0.1 mA can be provided by batteries contained within the delivery structure or alternatively by external structures which are periodically applied to the gingiva or appliances present over the gingiva. Similarly, ultrasound-enhanced substance delivery can be effected by transducers incorporated into the delivery appliances and/or provided by external appliances. Suitable ultrasound conditions are from 20 kHz to 100 kHz at energy levels of one to ten J/cm 2 . [0015] A particular advantage of the present invention is that particular teeth can be treated with the substance(s) while other teeth in the same jaw remain untreated. In this way, those teeth which are to be moved at any point during the course of orthodontic treatment may be “relaxed” and prepared for movement while other teeth which are needed as “anchor teeth” remain untreated. In this way, the wire and bracket system, removable aligner, or the like, may be anchored on those teeth which have not been treated with the substance(s), while those teeth which are intended to be moved may be treated and more readily moved. Of course, during a normal orthodontic treatment, different teeth will be targeted for movement at different times. The present invention allows only those teeth which are intended to be moved at any particular time to be treated at that time while other teeth in the dentition remain untreated during that time and available as anchor teeth for performing the orthodontic treatment. [0016] The present invention may also advantageously be combined with other orthodontic treatment protocols, such as electroosteogenesis where a small electrical current is applied to the gingiva or jaw to stimulate the tissues. It is believed that the combination of the substance(s) with such electroosteogenesis could provide tooth movement which is improved over that achieved with either approach alone. Moreover, the application of the electric current might act to provide “electroporation” and enhance the uptake of the substance(s) into the periodontal tissues, as described above. [0017] In a further aspect of the present invention, improved orthodontic treatment methods are provided. The orthodontic treatment methods are of the type where at least one tooth in a patient jaw is repositioned. The improvement comprises administering at least one tissue remodeling and/or an angiogenic substance to the patient before, during, or after the force has been applied. The preferred aspects of this method are generally the same as described above. [0018] The present invention still further provides oral delivery appliances comprising a structure and a tissue remodeling and/or an angiogenic substance(s). The structure is mountable on or over at least a portion of a patient gingiva, and the substance(s) is carried by the structure so that said substance(s) is release into at least a region of the gingiva while the structure is mounted on or over the gingiva. Typically, the delivery appliance mounts over the gingiva of an entire jaw, but in some instances it may mount over the gingiva of less than the entire jaw. Typically, the structure will include at least a portion which engages or mounts over the gingiva adjacent the roots of the target teeth, typically from one to twelve teeth, usually from one to six teeth, often from one to five teeth, and sometimes only a single tooth. The appliance may be in the form of a patch which adheres to the gingiva, a shell which is removably placeable over the teeth in the gingiva, or the like. The use of patches for delivery of the substance(s) may be particularly advantages since the patches can be cut to size in order to control dosage and/or delivery area to the gingiva. Such modified patches may be applied or adhered directly to the gingiva or alternatively may be positioned beneath a retainer which is worn to maintain the positions of the teeth. When wire and bracket orthodontic appliances are used, the delivery appliance may be formed to mount on the wire or onto the bracket, may be incorporated as part of the bracket or wire, or may be some combination thereof. The relaxin or other tissue remodeling and/or angiogenic substance may be incorporated into the oral delivery appliance in a variety of ways. Most commonly, the relaxin will be in a liquid, gel, or other releasable form which is incorporated into a time-release structure to apply the substance to the gingiva at a desired dosage rate. For example, the substance(s) may be incorporated into a porous structure and/or in a reservoir which is covered by a porous structure. In either case, the porous structure acts as a rate-controlling membrane or barrier to achieve the desired delivery rate. Alternatively, the substance(s) may be present in a biodegradable matrix which degrades in the oral environment over time to achieve a desired release rate of the substance. Suitable degradable substances include polymers, such as glycolic acid polymers and related materials. [0019] In a still further aspect of the present invention, topical oral compositions comprise a carrier and a tissue remodeling and/or an angiogenic substance(s). The carrier is of the type which may be topically applied to a patient's gingiva, typically being in the form of a gel, cream, ointment, microemulsion or other liquid. The tissue remodeling and/or an angiogenic substance(s) may be any of the substance(s) listed above. The composition may be provided in any conventional applicator, such as a tube, syringe, bottle, or the like, and will be maintained in a sterile condition within the applicator. BRIEF DESCRIPTION OF THE DRAWINGS [0020] FIG. 1 illustrates an oral tissue remodeling and/or an angiogenic substance(s) delivery appliance constructed in accordance with the principles of the present invention, in the form of a patch. [0021] FIG. 2 is a cross-sectional view taken along line 2 - 2 of FIG. 1 . [0022] FIG. 3 illustrates the use of the patch of FIG. 1 in a first exemplary protocol according to the present invention. [0023] FIG. 4 illustrates the use of the patch of FIG. 1 in a second exemplary protocol according to the present invention. [0024] FIG. 5 illustrates the use of a polymeric shell appliance for repositioning teeth and delivering a tissue remodeling and/or an angiogenic substance(s) according to the principles of the present invention. [0025] FIG. 6 is a photograph illustrating the section of the incisor which was excised for use in the push out testing described in the Experimental Section. [0026] FIG. 7 is a photograph illustrating the test equipment used for the push out testing. [0027] FIG. 8 is a graph showing the results of the push out testing. [0028] FIG. 9 is a photograph showing how the tooth wiggle testing was performed. [0029] FIGS. 10-13 are graphs showing the results of the pull out testing. [0030] FIG. 14 is a graph showing the results of the tooth wiggle testing. [0031] FIG. 15 illustrates the results of the dose response testing. DETAILED DESCRIPTION OF THE INVENTION [0032] The present invention provides improved and facilitated orthodontic treatment by delivering tissue remodeling and/or an angiogenic substance(s) to periodontal tissue in which the teeth to be moved are rooted or anchored. As used hereinafter, “periodontal tissue” will refer to the connective tissue within the periodontal tissues, specifically including the tissue and ligaments which anchor the teeth in the bone. The application of the tissue remodeling and/or an angiogenic substance(s) to the periodontal tissue will both loosen the tissue and ligaments as well as promote remodeling of the tissue during and after orthodontic treatment. [0033] The tissue remodeling and/or angiogenic substance(s) may be delivered to the periodontal tissue in a variety of ways, including systemic delivery, local injection, local topical application, continuously, periodically, and combinations thereof. Topical delivery is presently preferred and may be achieved using a conventional surface applicator, such as a brush, swab, syringe, squeeze tube, sponge, or other similar device. Alternatively, topical delivery may be effected using various controlled release devices, such as retainers, patches, orthodontic brackets and wires, and other appliances which may be positioned on or over the teeth and which have been modified in order to release the substance(s) to the gingiva. In some cases, it will be desired to deliver the drug into the gingival margin which is the line or groove along the gingiva-tooth interface. Substances may be applied as part of formulations which are delivered over the gingiva and/or into the sulcus. In some instances, it may be desirable to plant small substance delivery structures directly into the sulcus in a manner analogous to the delivery of antibiotics using systems, such as the PerioChip® available from Dexcel Pharma. The following specific examples of patches and structures for delivering the tissue remodeling and/or angiogenic substance(s) of the present invention are meant to be exemplary and not limiting. [0034] Referring to FIGS. 1 and 2 , the substance(s) may be applied in a variety of ways, including using a patch 10 which typically comprises a reservoir layer 12 , a rate controlling membrane 14 , and an adhesive layer 16 . A patch 10 may be cut into strips, smaller patches, or the like, and may be applied to the gingiva in order to effect topical delivery of the substance(s) from the reservoir into the tissue. [0035] As shown in FIG. 3 , the patch 10 of FIG. 1 may be cut into smaller strips or pieces 20 which may be placed over the gingiva overlying individual teeth. In this way, the teeth T 1 and T 2 , for example, may be treated to facilitate movement and promote periodontal tissue remodeling, according to the present invention, while adjacent teeth T 3 and T 4 , as well as other non-treated teeth, remain available as anchor teeth for effecting orthodontic treatment, typically using conventional wire and bracket systems (not shown). In FIG. 3B , the positioning of the patches 20 over the roots of the teeth is shown. [0036] In FIG. 4 , a continuous strip 30 of the patch material 10 is shown placed over the gingiva of eight adjacent teeth. The strip 30 , of course, could extend around the entire gingiva of one jaw. In this way, the substance(s) can be delivered to all teeth at once. Such treatment might be preferred, for example, for treating teeth after the teeth have reached their final position in order to promote tissue remodeling. Alternatively, the strip 30 could be configured so that the tissue remodeling and/or an angiogenic substance(s) are released only from particular locations on the strip to treat individual target teeth, achieving the same type of treatment as shown in FIG. 3 . Although patch and strip placement in FIGS. 3 and 4 is shown only on the labial side of the gingiva, the strips could be placed additionally or alternatively on the lingual side of the gingiva. [0037] Referring now to FIG. 5 , a dental retainer or aligner 40 is shown for placement over the dentition of a single jaw 42 . A crown portion 44 of a retainer/aligner 40 is configured to be removably positionable over the teeth, while a skirt portion 46 is configured to lie over the gingiva, usually both the labial and lingual sides of the gingiva. The skirt is configured to retain and release the tissue remodeling and/or an angiogenic substance(s), either over its entire surface or over selected regions 48 as shown. In this way, the substance(s) may be selectively delivered to individual teeth or to the entire dentition in a single jaw, depending on the particular treatment protocol. [0038] The following examples are offered by way of illustration, not by way of limitation. Experimental [0039] Two studies are presented, one examining properties of the periodontal and gingival tissues to relaxin and the second on dose finding. [0040] I. In Vivo Studies of the Periodontal Ligament [0041] A rat model was utilized because the rat has been historically used for many orthodontic studies. There were five animals per treatment group. Rats were treated for 1 or 3 days with human relaxin (H2 gene product) or vehicle control (Table 1 below). Relaxin or control vehicle was administered via Alzet implanted minipumps. In addition, relaxin treated rats received a 0.5 mg bolus injection (1.43 mg/kg) of relaxin at the time pumps were placed. TABLE 1 Days of Treatment Control Relaxin 1 Day C1 (n = 5) R1 (n = 5) 3 Days C3 (n = 5) R3 (n = 5) [0042] The jaws were collected for transport to the University of Washington for analysis. The day 1 jaws were delivered fresh, and the day 3 jaws were delivered frozen. Teeth from each treatment group were tested for “looseness” using a material testing device (MTD), and the periodontal ligament (PDL) was tested in a “push-out” test. The rest of the jaw was saved for histological analysis. [0043] II. Objectives [0044] These tests evaluated the ability of human relaxin (H2) to accelerate tooth movement during orthodontic procedures in a rat model. These studies examined the short term effects of relaxin on tooth looseness using circulating relaxin and a material testing device (MTD). [0045] A. Tooth Looseness Tooth displacement measured in response to a known force was measured. [0046] B. Push-Out Test The material properties of the PDL were measured in a material testing device to obtain force/displacement curves. [0047] C. Histological Analysis The contralateral jaw was used for histological analysis. Staining techniques were used to visualize collagen and elastin. [0048] III. Protocol [0049] A. Treatment Groups Adult male Sprague-Dawley rate (89-94 days old) were purchased from Animal Technologies, Ltd, Livermore, Calif. There were five animals per treatment group having body weights of 300-350 grams. Rats were treated for 1 or 3 days with human relaxin (H2 gene product) or vehicle control (Table 1). Relaxin or control vehicle is administered via Alzet implanted minipumps. In addition, relaxin treated rats received a 0.5 mg bolus injection (1.43 mg/kg) at the time pumps were placed. [0050] B. Relaxin Administration Human relaxin (H2) produced by Connetics, Corp was administered using Alzet osmotic pumps as previously described in the rat (Garber et al. (2001) Kidney Int. 59: 1184-85). Relaxin was administered at a rate of approximately 8 μg/kg/hr. This delivery rate has been shown to result in a blood concentration of approximately 150 ng/ml (Garber, Microchnik et al. 2001). To ensure relaxin levels rapidly achieved effective concentrations, rats were given a bolus subcutaneous injection of 0.5 mg relaxin at the time of pump implant. Control animals received the same volume of vehicle. [0051] C. Animal Manipulations Animals were euthanized with anesthesia overdose at each of the specified time intervals. Maxillae were dissected into halves. One hemimaxilla was fixed in 10% formalin for 24 hours followed by decalcification in 10% EDTA for two weeks with daily changes of the solution, dehydration in increasing concentrations of ethanol, and embedding in paraffin for immunohistochemical and histomorphometric analyses. The other hemimaxilla was fixed, decalcified and frozen for the immunohistochemical analyses. Calvarias were saved for examination of sutures by similar procedures. [0052] D. Measuring Tooth Movement [0053] 1. Push Out Test Gingival tissues were dissected away, and a 2 mm disk was cut through the alveolar bone and incisor ( FIG. 6 ). The resulting disk had alveolar bone, periodontal ligament (PDL), tooth, and pulp and was embedded in paraffin. The embedded tissue block was loaded onto a material testing device ( FIG. 7 ) to produce the stress-strain curve shown in FIG. 8 . Stress = load cross ⁢ - ⁢ sectional ⁢   ⁢   ⁢ area = kg ⁢ / ⁢ mm 2 Strain = elongation original ⁢   ⁢   ⁢ length = % ⁢   ⁢ elongation [0054] 2. Wiggle Test The second premolar tooth was embedded in paraffin and wiggled in place ( FIG. 9 ). The amount of movement was recorded. [0055] The resulting amount of displacement was measured repeatedly and averaged for each specimen. [0056] IV. Results and Analysis [0057] A. Material Testing The material testing of the rat jaws included two different tests. These were the “push-out” test, and the “wiggle” test. Separate teeth were used for each of these tests, as explained below. The Day I specimens were delivered fresh while the Day 3 were frozen so are only directly comparable with the controls for that day. [0058] 1. Push-Out Test The push-out test resulted in many different parameters of a stress strain curve. Several of the more relevant parameters were selected for the following graphs. [0059] Referring to FIG. 10 , peak load is a measure of the maximum load (kilograms) that the PDL can withstand before breaking. The PDL appears to be “weaker” with relaxin treatment, either at day 1 or day 3 of treatment. [0060] Referring to FIG. 11 , break load is the force in kilograms needed to break the PDL. It was observed that the force was less with relaxin treatment, indicating a softening of the ligament. [0061] Referring to FIG. 12 , energy is the area under the curve of the force needed to break the PDL. Again, relaxin resulted in less energy needed to break the PDL indicating its lessened resistance to force. [0062] Referring to FIG. 13 , yield stress is the amount of stress (kilograms/square mm) needed to cause the PDL to yield. The effect of relaxin was to lower this parameter, indicating the ligament was softer. [0063] 2. Tooth Wiggle Referring to FIG. 14 , the tooth wiggle test demonstrated that the tooth was looser in the relaxin treated animals. This was especially prominent in the day 1 treated animals. The smaller difference seen on day 3 may be due to freezing the tissue. [0064] B. Histological Analysis The specimens were decalcified, embedded, sectioned and strained with a variety of histological stains. The PDL and gingival connective tissue were examined for a reduction and/or reorganization in the collagen. Collagen normally has a highly regular structure, which can be observed under a microscope using polarized light. Intact collagen demonstrates a birefringence or glow which is lost upon breakdown of the collagen. [0065] Comparison of the treated collagen with the untreated control, under polarized label, demonstrated that the relaxin had broken down the collagen. In the relaxin treated animals, the collagen fibers have been shortened and no longer have the parallel arrangement. [0066] V. Dose Finding Experiment [0067] The following test helps determine an effective dose of relaxin for modification of collagen in the PDL and gingival tissues. Relaxin was administered in different doses to the rat for 5 days via Alzet subcutaneous pumps. Again the material testing device was used for measurement of the effects of relaxin. The results are shown in FIG. 15 . [0068] The modulus is the slope of the stress strain graph. This figure suggests a dose relationship of relaxin with the softening of the PDL. It appears that even the lowest dose had modest effects on the PDL, indicating that a small amount of relaxin would be effective. [0069] VI. Summary of Data [0070] These data demonstrate for the first time that relaxin is effective in vivo in modifying the mechanical characteristics the ligaments that hold the tooth in the jaw. Major effects appear to be on the collagen which comprises a large portion of the PDL and gingival fibers. Relaxin affects these fibers as demonstrated by histological and physical measurements. The result of this modification of PDL and gingival fibers is to accelerate tooth movement and prevent relapse. Our data on dose indicate that even small amounts of relaxin may be effective in achieving these effects. [0071] While the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims.
Orthodontic methods comprise applying force to reposition teeth and administering a tissue remodeling and/or an angiogenic substance(s) to the periodontal tissue surrounding the teeth to be moved. The substance(s) may be delivered before, during, or after the teeth are moved, and the substance(s) may be selectively applied only to those teeth undergoing movement at any particular time. The substance(s) may be applied from the dental repositioning appliance or may be applied separately, either topically or by injection.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "[0001] This application is a continuation of application Ser.", "No. 10/695,299, filed on Oct. 27, 2003, which claims the benefit of U.S. Provisional Application No. 60/423,026, filed on Nov. 1, 2002, the full disclosures of which are incorporated herein by reference.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] The present invention relates generally to medical apparatus and methods.", "More particularly, the present invention relates to methods and systems for facilitating, accelerating, and stabilizing tooth movement before, during and after orthodontic procedures.", "[0004] Orthodontic procedures suffer from four major problems.", "First, the braces or other appliances which effect the tooth movement must be worn for long periods of time.", "Second, even after a successful orthodontic treatment, the teeth often relapse towards their original positions once the braces or other treatment appliances are removed.", "Third, the mechanically induced movement of teeth can cause significant discomfort to the patient.", "Fourth, the wearing of braces is esthetically displeasing, uncomfortable, and compromises oral hygiene.", "While recently introduced clear plastic visible “aligners”", "largely overcome the latter problems, such aligners are not suitable for all patients.", "Moreover, the aligners do not reduce treatment time, do not reduce the risk of relapse, and do not lessen the pain associated with tooth movement in the jaw.", "[0005] For these reasons, it would be desirable to provide improved orthodontic technologies for moving teeth which overcome at least some of the problems noted above.", "In particular, it would be desirable to provide orthodontic methods and systems which can reduce the time necessary to effect a desired tooth movement, which can reduce the pain associated with tooth movement, which can reduce the tendency of teeth to relapse to their original positions after the orthodontic treatment is stopped, and/or which can reduce the time in which unsightly braces need to be worn.", "[0006] 2.", "Description of Background Art [0007] Nicozisis et al.", "(2000) Clin.", "Orthod.", "Res.", "3:192-201, describes experiments which demonstrate the presence of endogenous relaxin in cranial tissue of mice and speculates that relaxin may be used as an adjunct to orthodontic or surgical therapy to promote manipulation of sutural tissues or affect stability.", "The application of electrical current to stimulate bone growth and remodeling in orthodontic procedures is described in U.S. Pat. Nos. 4,854,865;", "4,519,779;", "and 4,153,060.", "Appliances for local and systematic drug delivery to the gingival tissues are described in U.S. Pat. Nos. 6,159,498, 5,633,000;", "5,616,315;", "5,575,655;", "5,447,725;", "5,294,004;", "4,959,220;", "4,933,183;", "4,892,736;", "4,685,883;", "and Re.", "34,656.", "Polymeric shell appliances for repositioning teeth are described in U.S. Pat. No. 5,975,893.", "The full disclosures of each of the above U.S. patents are incorporated herein by reference.", "BRIEF SUMMARY OF THE INVENTION [0008] The present invention provides improved methods and systems for repositioning teeth in patients.", "In addition, the present invention provides improved methods and systems for stabilizing teeth which have already been repositioned in order to reduce or eliminate the tendency of the repositioned teeth to relapse, i.e., move back toward their prior positions.", "The methods for repositioning teeth comprise applying force to at least one tooth, and typically to more than one tooth and/or to different teeth over time, in the jaw of the patient.", "For both repositioning or stabilizing, tissue remodeling and/or an angiogenic substance(s) is administered to the patient to promote remodeling of periodontal tissue surrounding the root(s) of the tooth or teeth to be moved.", "Preferred substance(s) will bind to and activate the relaxin receptor in the tissues which anchor the teeth or other craniofacial structures.", "Most preferred is relaxin or an analog or mimetic thereof which combines tissue remodeling activity with angiogenic activity.", "Analogs include peptides, oligomers, fragments, etc.", "which comprise the active region of native relaxin and mimetics include small molecule drugs, typically below 2 kD, designed to mimic the activity of native relaxin.", "Alternatively, substance(s) with predominantly angiogenic activity could be selected, such as VEGF, bFGF, estrogen, nitrous oxide, naltrexone, or the like.", "Further alternatively, collagenases or other tissue-softening enzymes could be utilized to promote periodontal tissue remodeling according to the present invention.", "In some instances, it may be desirable to combine two or more tissue remodeling and/or angiogenic substance(s) having differing activities.", "In other instances it may be desirable to deliver different tissue remodeling and/or angiogenic substance(s) at different times during the orthodontic treatment and/or to different regions of the periodontal tissue.", "[0009] The term “relaxin”", "means human relaxin, including intact full length relaxin or a portion of the relaxin molecule that retains biological activity [as described in U.S. Pat. No. 5,023,321, preferably recombinant human relaxin (H2)] and other active agents with relaxin-like activity, such as Relaxin and portions that retain biological activity Like Factor (as described in U.S. Pat. No. 5,911,997 at SEQ ID NOS: 3 and 4, and column 5, line 27-column 6, line 4), relaxin analogs and portions that retain biological activity (as described in U.S. Pat. No. 5,811,395 at SEQ ID NOS: 1 and 2, and column 3, lines 16-40), and agents that competitively displace bound relaxin from a receptor.", "Relaxin can be made by any method known to those skilled in the art, for example, as described in any of U.S. Pat. Nos. 5,759,807;", "4,835,251 and co-pending U.S. Ser.", "No. 07/908,766 (PCT US90/02085) and Ser.", "No. 08/080,354 (PCT US94/0699).", "[0010] The tissue remodeling and/or angiogenic substance(s) will be delivered at a delivery rate and a total dosage which are selected to facilitate tooth repositioning and tissue remodeling.", "Typically, the dosage rates will be in the range from 1 ng to 500 μg per day, usually from 10 ng/day to 20 μg/day, preferably from 20 ng/day to 10 μg/day.", "The dosage and other aspects of the delivery may be adjusted from time-to-time in response to the effectiveness of treatment, such as the resistance of a particular tooth or group of teeth, where the dosage might be increased if resistance is not sufficiently reduced in response to an initial dosage.", "[0011] The substance(s) may be delivered at any point during the orthodontic treatment where tooth repositioning and/or tissue remodeling may be promoted.", "For example, the substance(s) may be applied prior to any application of force intended to move the teeth.", "Additionally or alternatively, the substance(s) may be applied during all or any portion of the time during which force is being applied to move the teeth.", "Further additionally or alternatively, the substance(s) may be applied after the teeth have been repositioned to a final desired configuration.", "In the latter case, application of the substance(s) may be particularly effective for promoting tissue remodeling in order to reduce the risk of relapse.", "In such instances, the substance(s) may be delivered using retainers or other appliances intended to help maintain the teeth in their desired final configuration.", "When being delivered to inhibit relapse, the remodeling and/or angiogenic substance(s) may be delivered for a limited period of time in a limited period before and/or immediately following the end of the orthodontic procedure or may be delivered continuously or periodically for long periods of time or indefinitely following the end of the orthodontic procedure.", "For example, the substance(s) may be delivered to some or preferably all of the regions of the gingiva where teeth have been moved in order to promote stabilization and remodeling of the tissue, usually over a period of one to eight weeks, more usually two to six weeks prior to the end of treatment.", "[0012] The teeth may be repositioned by any conventional orthodontic appliance intended for applying force to move teeth.", "In particular, the present invention is compatible with both the use of wire and bracket systems, commonly referred to as “braces,” as well as with newer systems employing removable appliances for repositioning teeth, such as the Invisalign® System, available from Align Technology, Inc., Santa Clara, Calif.", ", and the “red, white, and blue”", "system available from Sybron Dental Specialties, Irvine, Calif.", "The present invention will also be useful with dental “positioners”", "which are elastomeric appliances having pre-formed tooth-receiving cavities where the patient bites into the elastomeric appliance in order to force tooth movement.", "Finally, the present invention may be used with dental retainers which are polymeric shell appliances typically used to maintain a final, desired tooth configuration and prevent relapse.", "When used with dental repositioning appliances of any type, the application of the tissue remodeling and/or angiogenic substance(s) according to the present invention will usually both facilitate tooth movement by modifying the tissue structures within the periodontal tissue which anchor the teeth and also promoting tissue remodeling which allows such tissue structures to accommodate the repositioned teeth with less tendency toward relapse.", "[0013] The substance(s) of the present invention may be applied and administered in a wide variety of ways.", "Most simply, and as presently preferred, the substance(s) could be “painted”", "or otherwise topically applied to the patient's gingiva using a conventional single-use applicator such as a swab, brush, syringe, or the like.", "The substance(s) may be prepared in a conventional form of topical composition, such as a gel, cream, ointment, or other fluid or liquid substance.", "Alternatively, the substance(s) could be administered by injecting into the periodontal tissue.", "Additionally, the substance(s) could be delivered using a patch or other appliance which is worn on the teeth or gingiva, optionally being formed as part of the same appliance which is used to move the teeth, e.g., a bracket or removable shell appliance or retainer.", "In such instances, the substance(s) may be incorporated into conventional drug reservoirs which both maintain a supply of the substance(s) and which release the substance(s) at a controlled rate, over time, to target sites on the gingiva.", "Suitable drug delivery structures for delivering the substance(s) to the patient gingiva are described in the patent and medical literature, see, e.g., U.S. Pat. Nos. 6,159,498, 5,575,655;", "5,194,003;", "4,933,182;", "and 4,685,883, the full disclosures of which are incorporated herein by reference.", "[0014] In some instances, it may be desirable to provide for enhanced penetration of the substance(s) into the gingival.", "For example, the substance(s) could be formulated with tissue penetration or permeation enhancers, such as dimethylsulfoxide (DMSO).", "Alternatively or additionally, the substance(s) can be delivered while applying energy in a manner to promote tissue penetration, including the application of an electric current in order to achieve electroporation or iontophoresis, and/or the application of ultrasound energy.", "The currents needed to provide for electroporation are relatively low, typically around 0.1 mA can be provided by batteries contained within the delivery structure or alternatively by external structures which are periodically applied to the gingiva or appliances present over the gingiva.", "Similarly, ultrasound-enhanced substance delivery can be effected by transducers incorporated into the delivery appliances and/or provided by external appliances.", "Suitable ultrasound conditions are from 20 kHz to 100 kHz at energy levels of one to ten J/cm 2 .", "[0015] A particular advantage of the present invention is that particular teeth can be treated with the substance(s) while other teeth in the same jaw remain untreated.", "In this way, those teeth which are to be moved at any point during the course of orthodontic treatment may be “relaxed”", "and prepared for movement while other teeth which are needed as “anchor teeth”", "remain untreated.", "In this way, the wire and bracket system, removable aligner, or the like, may be anchored on those teeth which have not been treated with the substance(s), while those teeth which are intended to be moved may be treated and more readily moved.", "Of course, during a normal orthodontic treatment, different teeth will be targeted for movement at different times.", "The present invention allows only those teeth which are intended to be moved at any particular time to be treated at that time while other teeth in the dentition remain untreated during that time and available as anchor teeth for performing the orthodontic treatment.", "[0016] The present invention may also advantageously be combined with other orthodontic treatment protocols, such as electroosteogenesis where a small electrical current is applied to the gingiva or jaw to stimulate the tissues.", "It is believed that the combination of the substance(s) with such electroosteogenesis could provide tooth movement which is improved over that achieved with either approach alone.", "Moreover, the application of the electric current might act to provide “electroporation”", "and enhance the uptake of the substance(s) into the periodontal tissues, as described above.", "[0017] In a further aspect of the present invention, improved orthodontic treatment methods are provided.", "The orthodontic treatment methods are of the type where at least one tooth in a patient jaw is repositioned.", "The improvement comprises administering at least one tissue remodeling and/or an angiogenic substance to the patient before, during, or after the force has been applied.", "The preferred aspects of this method are generally the same as described above.", "[0018] The present invention still further provides oral delivery appliances comprising a structure and a tissue remodeling and/or an angiogenic substance(s).", "The structure is mountable on or over at least a portion of a patient gingiva, and the substance(s) is carried by the structure so that said substance(s) is release into at least a region of the gingiva while the structure is mounted on or over the gingiva.", "Typically, the delivery appliance mounts over the gingiva of an entire jaw, but in some instances it may mount over the gingiva of less than the entire jaw.", "Typically, the structure will include at least a portion which engages or mounts over the gingiva adjacent the roots of the target teeth, typically from one to twelve teeth, usually from one to six teeth, often from one to five teeth, and sometimes only a single tooth.", "The appliance may be in the form of a patch which adheres to the gingiva, a shell which is removably placeable over the teeth in the gingiva, or the like.", "The use of patches for delivery of the substance(s) may be particularly advantages since the patches can be cut to size in order to control dosage and/or delivery area to the gingiva.", "Such modified patches may be applied or adhered directly to the gingiva or alternatively may be positioned beneath a retainer which is worn to maintain the positions of the teeth.", "When wire and bracket orthodontic appliances are used, the delivery appliance may be formed to mount on the wire or onto the bracket, may be incorporated as part of the bracket or wire, or may be some combination thereof.", "The relaxin or other tissue remodeling and/or angiogenic substance may be incorporated into the oral delivery appliance in a variety of ways.", "Most commonly, the relaxin will be in a liquid, gel, or other releasable form which is incorporated into a time-release structure to apply the substance to the gingiva at a desired dosage rate.", "For example, the substance(s) may be incorporated into a porous structure and/or in a reservoir which is covered by a porous structure.", "In either case, the porous structure acts as a rate-controlling membrane or barrier to achieve the desired delivery rate.", "Alternatively, the substance(s) may be present in a biodegradable matrix which degrades in the oral environment over time to achieve a desired release rate of the substance.", "Suitable degradable substances include polymers, such as glycolic acid polymers and related materials.", "[0019] In a still further aspect of the present invention, topical oral compositions comprise a carrier and a tissue remodeling and/or an angiogenic substance(s).", "The carrier is of the type which may be topically applied to a patient's gingiva, typically being in the form of a gel, cream, ointment, microemulsion or other liquid.", "The tissue remodeling and/or an angiogenic substance(s) may be any of the substance(s) listed above.", "The composition may be provided in any conventional applicator, such as a tube, syringe, bottle, or the like, and will be maintained in a sterile condition within the applicator.", "BRIEF DESCRIPTION OF THE DRAWINGS [0020] FIG. 1 illustrates an oral tissue remodeling and/or an angiogenic substance(s) delivery appliance constructed in accordance with the principles of the present invention, in the form of a patch.", "[0021] FIG. 2 is a cross-sectional view taken along line 2 - 2 of FIG. 1 .", "[0022] FIG. 3 illustrates the use of the patch of FIG. 1 in a first exemplary protocol according to the present invention.", "[0023] FIG. 4 illustrates the use of the patch of FIG. 1 in a second exemplary protocol according to the present invention.", "[0024] FIG. 5 illustrates the use of a polymeric shell appliance for repositioning teeth and delivering a tissue remodeling and/or an angiogenic substance(s) according to the principles of the present invention.", "[0025] FIG. 6 is a photograph illustrating the section of the incisor which was excised for use in the push out testing described in the Experimental Section.", "[0026] FIG. 7 is a photograph illustrating the test equipment used for the push out testing.", "[0027] FIG. 8 is a graph showing the results of the push out testing.", "[0028] FIG. 9 is a photograph showing how the tooth wiggle testing was performed.", "[0029] FIGS. 10-13 are graphs showing the results of the pull out testing.", "[0030] FIG. 14 is a graph showing the results of the tooth wiggle testing.", "[0031] FIG. 15 illustrates the results of the dose response testing.", "DETAILED DESCRIPTION OF THE INVENTION [0032] The present invention provides improved and facilitated orthodontic treatment by delivering tissue remodeling and/or an angiogenic substance(s) to periodontal tissue in which the teeth to be moved are rooted or anchored.", "As used hereinafter, “periodontal tissue”", "will refer to the connective tissue within the periodontal tissues, specifically including the tissue and ligaments which anchor the teeth in the bone.", "The application of the tissue remodeling and/or an angiogenic substance(s) to the periodontal tissue will both loosen the tissue and ligaments as well as promote remodeling of the tissue during and after orthodontic treatment.", "[0033] The tissue remodeling and/or angiogenic substance(s) may be delivered to the periodontal tissue in a variety of ways, including systemic delivery, local injection, local topical application, continuously, periodically, and combinations thereof.", "Topical delivery is presently preferred and may be achieved using a conventional surface applicator, such as a brush, swab, syringe, squeeze tube, sponge, or other similar device.", "Alternatively, topical delivery may be effected using various controlled release devices, such as retainers, patches, orthodontic brackets and wires, and other appliances which may be positioned on or over the teeth and which have been modified in order to release the substance(s) to the gingiva.", "In some cases, it will be desired to deliver the drug into the gingival margin which is the line or groove along the gingiva-tooth interface.", "Substances may be applied as part of formulations which are delivered over the gingiva and/or into the sulcus.", "In some instances, it may be desirable to plant small substance delivery structures directly into the sulcus in a manner analogous to the delivery of antibiotics using systems, such as the PerioChip® available from Dexcel Pharma.", "The following specific examples of patches and structures for delivering the tissue remodeling and/or angiogenic substance(s) of the present invention are meant to be exemplary and not limiting.", "[0034] Referring to FIGS. 1 and 2 , the substance(s) may be applied in a variety of ways, including using a patch 10 which typically comprises a reservoir layer 12 , a rate controlling membrane 14 , and an adhesive layer 16 .", "A patch 10 may be cut into strips, smaller patches, or the like, and may be applied to the gingiva in order to effect topical delivery of the substance(s) from the reservoir into the tissue.", "[0035] As shown in FIG. 3 , the patch 10 of FIG. 1 may be cut into smaller strips or pieces 20 which may be placed over the gingiva overlying individual teeth.", "In this way, the teeth T 1 and T 2 , for example, may be treated to facilitate movement and promote periodontal tissue remodeling, according to the present invention, while adjacent teeth T 3 and T 4 , as well as other non-treated teeth, remain available as anchor teeth for effecting orthodontic treatment, typically using conventional wire and bracket systems (not shown).", "In FIG. 3B , the positioning of the patches 20 over the roots of the teeth is shown.", "[0036] In FIG. 4 , a continuous strip 30 of the patch material 10 is shown placed over the gingiva of eight adjacent teeth.", "The strip 30 , of course, could extend around the entire gingiva of one jaw.", "In this way, the substance(s) can be delivered to all teeth at once.", "Such treatment might be preferred, for example, for treating teeth after the teeth have reached their final position in order to promote tissue remodeling.", "Alternatively, the strip 30 could be configured so that the tissue remodeling and/or an angiogenic substance(s) are released only from particular locations on the strip to treat individual target teeth, achieving the same type of treatment as shown in FIG. 3 .", "Although patch and strip placement in FIGS. 3 and 4 is shown only on the labial side of the gingiva, the strips could be placed additionally or alternatively on the lingual side of the gingiva.", "[0037] Referring now to FIG. 5 , a dental retainer or aligner 40 is shown for placement over the dentition of a single jaw 42 .", "A crown portion 44 of a retainer/aligner 40 is configured to be removably positionable over the teeth, while a skirt portion 46 is configured to lie over the gingiva, usually both the labial and lingual sides of the gingiva.", "The skirt is configured to retain and release the tissue remodeling and/or an angiogenic substance(s), either over its entire surface or over selected regions 48 as shown.", "In this way, the substance(s) may be selectively delivered to individual teeth or to the entire dentition in a single jaw, depending on the particular treatment protocol.", "[0038] The following examples are offered by way of illustration, not by way of limitation.", "Experimental [0039] Two studies are presented, one examining properties of the periodontal and gingival tissues to relaxin and the second on dose finding.", "[0040] I. In Vivo Studies of the Periodontal Ligament [0041] A rat model was utilized because the rat has been historically used for many orthodontic studies.", "There were five animals per treatment group.", "Rats were treated for 1 or 3 days with human relaxin (H2 gene product) or vehicle control (Table 1 below).", "Relaxin or control vehicle was administered via Alzet implanted minipumps.", "In addition, relaxin treated rats received a 0.5 mg bolus injection (1.43 mg/kg) of relaxin at the time pumps were placed.", "TABLE 1 Days of Treatment Control Relaxin 1 Day C1 (n = 5) R1 (n = 5) 3 Days C3 (n = 5) R3 (n = 5) [0042] The jaws were collected for transport to the University of Washington for analysis.", "The day 1 jaws were delivered fresh, and the day 3 jaws were delivered frozen.", "Teeth from each treatment group were tested for “looseness”", "using a material testing device (MTD), and the periodontal ligament (PDL) was tested in a “push-out”", "test.", "The rest of the jaw was saved for histological analysis.", "[0043] II.", "Objectives [0044] These tests evaluated the ability of human relaxin (H2) to accelerate tooth movement during orthodontic procedures in a rat model.", "These studies examined the short term effects of relaxin on tooth looseness using circulating relaxin and a material testing device (MTD).", "[0045] A. Tooth Looseness Tooth displacement measured in response to a known force was measured.", "[0046] B. Push-Out Test The material properties of the PDL were measured in a material testing device to obtain force/displacement curves.", "[0047] C. Histological Analysis The contralateral jaw was used for histological analysis.", "Staining techniques were used to visualize collagen and elastin.", "[0048] III.", "Protocol [0049] A. Treatment Groups Adult male Sprague-Dawley rate (89-94 days old) were purchased from Animal Technologies, Ltd, Livermore, Calif.", "There were five animals per treatment group having body weights of 300-350 grams.", "Rats were treated for 1 or 3 days with human relaxin (H2 gene product) or vehicle control (Table 1).", "Relaxin or control vehicle is administered via Alzet implanted minipumps.", "In addition, relaxin treated rats received a 0.5 mg bolus injection (1.43 mg/kg) at the time pumps were placed.", "[0050] B. Relaxin Administration Human relaxin (H2) produced by Connetics, Corp was administered using Alzet osmotic pumps as previously described in the rat (Garber et al.", "(2001) Kidney Int.", "59: 1184-85).", "Relaxin was administered at a rate of approximately 8 μg/kg/hr.", "This delivery rate has been shown to result in a blood concentration of approximately 150 ng/ml (Garber, Microchnik et al.", "2001).", "To ensure relaxin levels rapidly achieved effective concentrations, rats were given a bolus subcutaneous injection of 0.5 mg relaxin at the time of pump implant.", "Control animals received the same volume of vehicle.", "[0051] C. Animal Manipulations Animals were euthanized with anesthesia overdose at each of the specified time intervals.", "Maxillae were dissected into halves.", "One hemimaxilla was fixed in 10% formalin for 24 hours followed by decalcification in 10% EDTA for two weeks with daily changes of the solution, dehydration in increasing concentrations of ethanol, and embedding in paraffin for immunohistochemical and histomorphometric analyses.", "The other hemimaxilla was fixed, decalcified and frozen for the immunohistochemical analyses.", "Calvarias were saved for examination of sutures by similar procedures.", "[0052] D. Measuring Tooth Movement [0053] 1.", "Push Out Test Gingival tissues were dissected away, and a 2 mm disk was cut through the alveolar bone and incisor ( FIG. 6 ).", "The resulting disk had alveolar bone, periodontal ligament (PDL), tooth, and pulp and was embedded in paraffin.", "The embedded tissue block was loaded onto a material testing device ( FIG. 7 ) to produce the stress-strain curve shown in FIG. 8 .", "Stress = load cross ⁢ - ⁢ sectional ⁢ ⁢ ⁢ area = kg ⁢ / ⁢ mm 2 Strain = elongation original ⁢ ⁢ ⁢ length = % ⁢ ⁢ elongation [0054] 2.", "Wiggle Test The second premolar tooth was embedded in paraffin and wiggled in place ( FIG. 9 ).", "The amount of movement was recorded.", "[0055] The resulting amount of displacement was measured repeatedly and averaged for each specimen.", "[0056] IV.", "Results and Analysis [0057] A. Material Testing The material testing of the rat jaws included two different tests.", "These were the “push-out”", "test, and the “wiggle”", "test.", "Separate teeth were used for each of these tests, as explained below.", "The Day I specimens were delivered fresh while the Day 3 were frozen so are only directly comparable with the controls for that day.", "[0058] 1.", "Push-Out Test The push-out test resulted in many different parameters of a stress strain curve.", "Several of the more relevant parameters were selected for the following graphs.", "[0059] Referring to FIG. 10 , peak load is a measure of the maximum load (kilograms) that the PDL can withstand before breaking.", "The PDL appears to be “weaker”", "with relaxin treatment, either at day 1 or day 3 of treatment.", "[0060] Referring to FIG. 11 , break load is the force in kilograms needed to break the PDL.", "It was observed that the force was less with relaxin treatment, indicating a softening of the ligament.", "[0061] Referring to FIG. 12 , energy is the area under the curve of the force needed to break the PDL.", "Again, relaxin resulted in less energy needed to break the PDL indicating its lessened resistance to force.", "[0062] Referring to FIG. 13 , yield stress is the amount of stress (kilograms/square mm) needed to cause the PDL to yield.", "The effect of relaxin was to lower this parameter, indicating the ligament was softer.", "[0063] 2.", "Tooth Wiggle Referring to FIG. 14 , the tooth wiggle test demonstrated that the tooth was looser in the relaxin treated animals.", "This was especially prominent in the day 1 treated animals.", "The smaller difference seen on day 3 may be due to freezing the tissue.", "[0064] B. Histological Analysis The specimens were decalcified, embedded, sectioned and strained with a variety of histological stains.", "The PDL and gingival connective tissue were examined for a reduction and/or reorganization in the collagen.", "Collagen normally has a highly regular structure, which can be observed under a microscope using polarized light.", "Intact collagen demonstrates a birefringence or glow which is lost upon breakdown of the collagen.", "[0065] Comparison of the treated collagen with the untreated control, under polarized label, demonstrated that the relaxin had broken down the collagen.", "In the relaxin treated animals, the collagen fibers have been shortened and no longer have the parallel arrangement.", "[0066] V. Dose Finding Experiment [0067] The following test helps determine an effective dose of relaxin for modification of collagen in the PDL and gingival tissues.", "Relaxin was administered in different doses to the rat for 5 days via Alzet subcutaneous pumps.", "Again the material testing device was used for measurement of the effects of relaxin.", "The results are shown in FIG. 15 .", "[0068] The modulus is the slope of the stress strain graph.", "This figure suggests a dose relationship of relaxin with the softening of the PDL.", "It appears that even the lowest dose had modest effects on the PDL, indicating that a small amount of relaxin would be effective.", "[0069] VI.", "Summary of Data [0070] These data demonstrate for the first time that relaxin is effective in vivo in modifying the mechanical characteristics the ligaments that hold the tooth in the jaw.", "Major effects appear to be on the collagen which comprises a large portion of the PDL and gingival fibers.", "Relaxin affects these fibers as demonstrated by histological and physical measurements.", "The result of this modification of PDL and gingival fibers is to accelerate tooth movement and prevent relapse.", "Our data on dose indicate that even small amounts of relaxin may be effective in achieving these effects.", "[0071] While the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used.", "Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application Ser. No. 60/782,928 filed Mar. 16, 2006, which application is hereby incorporated by reference to the same extent as though fully disclosed herein. FIELD OF INVENTION [0002] This application relates to the field of photomasks, referred to in the trade as reticles, used in the production of semiconductor devices, and more particularly to such reticles that are sensitive to electrical fields. BACKGROUND OF THE INVENTION [0003] Transmission photomasks (reticles) used in the production of semiconductor devices are often constructed using conductive metallic films (for example, chromium), or other films, such as MoSiON, deposited onto a transparent substrate, such as quartz. A pattern is etched into this film and then is projected by photo-reduction onto a semiconductor wafer coated with a photosensitive layer. By this means, a replica of the pattern on the reticle is produced in the film on the semiconductor wafer, which replica is greatly reduced in size. Through further and repeated processing of the wafer, a three-dimensional microcircuit is built up. [0004] Such reticles may contain a multitude of isolated conductive features supported on an electrically insulating substrate. These conductive features, which together make up the pattern that is to be projected onto the wafer, can have differing electrical potentials induced on them if the reticle is placed into an electric field. The presence of differing electric potentials on neighboring conductive features can cause electrical discharge between the features in a process that is referred to as field-induced electrostatic discharge (ESD). Furthermore, the features may also be damaged by such induced potentials even when an electrostatic discharge does not take place in a process referred to as electric field-induced material migration (EFM). [0005] The degree of damage that a reticle will suffer as a result of such exposure to an electric field is difficult to predict, since the induction process is dependent upon the detailed structure of the pattern on the reticle, its orientation with respect to the electric field, and its proximity to surrounding objects which might perturb the electric field and concentrate such field through certain areas of the pattern. This makes it difficult to define how frequently a reticle should be inspected for damage in normal use to prevent production of defective wafers. Furthermore, any electric field-induced damage that is sustained by a reticle maybe subtle, highly localized, and difficult to detect during routine reticle inspections. Even though the damage may not be detected in the reticle inspection tool, it may affect the lithographic process. [0006] The damage to the reticle may cause the image projected on the wafer to deviate from that which is expected and which is required for correct functioning of the finished semiconductor device. This is referred to as Critical Dimension (CD) deviation. When a reticle becomes damaged in such a way, defective devices can be produced; and this may not be discovered until the complete device has been built and is tested. Discovery of defects at this late stage in the production process results in significant financial losses to the semiconductor industry. [0007] Electrostatic damage to reticles has been such a prevalent factor in semiconductor production for many years that various novel approaches have been suggested for countering it. In 1984, U.S. Pat. No. 4,440,841 described one of the first methods for making a reticle with an integral conductive layer capable of dissipating electrostatic charge. In 1985, JP Patent No. 60,222,856 described a means of connecting the various mask elements with filamentary conductive lines to avoid potential differences between them. Since those first two approaches, many variants involving conductive coatings, featuring interconnects, and charge dissipating structures have been proposed (e.g., JP Patent No. 62,293,244 (1987); U.S. Pat. No. 5,798,192 (1998); U.S. Pat. No. 5,989,754 (1999); KR Patent No. 196,585Y (2000); U.S. Pat. No. 6,180,291 (2001); TW Patent No. 441,071 (2001); KR Patent Publication No. 2001/057347 (2001); U.S. Pat. No. 6,291,114 (2001); U.S. Pat. No. 6,309,781 (2001); JP Patent Publication No. 2002/055438 (2002); US Patent Publication No. 2002/0115001(2002); U.S. Pat. No. 6,440,617 (2002); U.S. Pat. No. 6,569,576 B1 (2003); TW Patent No. 543,178 (2003); KR Patent Publication No. 2003/085946 (2003); JP Patent Publication No. 2004/061884 (2004); US Patent Publication No. 2004/076834 (2004); and U.S. Pat. No. 6,803,156 (2004)). These solutions increase the complexity and cost of reticle manufacture, plus they add process steps which can introduce defects or inhomogeneity to the reticle. Coatings may delaminate, or they may be easily damaged during handling and reticle cleaning. Furthermore, some of the coatings that have been suggested may degrade due to exposure to energetic UV light that is used in today's leading edge lithography systems; hence, their transparency may alter with time. All of these potential problems probably explain why such solutions are not in widespread use today and why reticle ESD damage continues to be a problem in the semiconductor manufacturing industry. [0008] If the reticle itself cannot be made inherently ESD protected, an alternative solution is to enclose the reticle inside a conductive container, which will provide ESD protection by shielding the reticle from electric fields. Such a solution is described in PCT Publication No. WO 2004/032208. This will protect the reticle while it is inside the container; but semiconductor manufacturing requires the reticle to be moved outside the container on many occasions, during which time the reticle might be exposed to electric fields. Since electric field exposure during normal use of the reticle may gradually change the image on the reticle in a way that is detrimental to the final device that is being manufactured, it is important to be able to monitor a reticle's exposure to electric fields. [0009] US Patent Publication No. 2003/0052691 describes a portable, compact sensor device that is capable of detecting the ESD events in a semiconductor manufacturing facility through their radio emissions. This has been suggested as a means of detecting ESD events in reticles by placing a sensor in the reticle handling environment or in/on the reticle carrier. However, such RF pulse sensing devices can only report the ESD event after the reticle is damaged, and EFM cannot be detected since there is no electrical discharge event. They also are likely to be sensitive to false alarms, owing to the highly charged nature of a semiconductor manufacturing facility. [0010] A more effective and reliable means is required for routinely sensing whether a reticle has been exposed to an electric field. Such a sensor that could warn of a hazardous exposure before the reticle itself becomes damaged would be very desirable. BRIEF SUMMARY OF THE INVENTION [0011] The present invention advances the reticle art by solving one or more of the above problems. [0012] The coupling of an electric field through a reticle is strongly affected by the presence of a continuous conductive border on the substrate. Such a border normally is present to prevent unwanted light from passing into the optical system of the lithography tool that is being used to print the reticle image onto the semiconductor wafer. This border sometimes is referred to as a “guard ring”; and it may also contain other structures such as alignment marks, bar codes, and human readable codes for identification of the reticle. It is separated from the image area by a clear space, and this electrically isolates the features in the image area from the guard ring. [0013] Owing to the nature of the interaction of the guard ring with any electric field that impinges on the reticle, the electric field is perturbed such that its direction and strength are altered. A feature of the invention is that this interaction preferably is such that the field strength within the plane of the reticle is greatest in the region of the image closest to the guard ring. Thus, any electric-field-induced damage that the reticle suffers should be most severe in these areas. Thus, the guard ring may concentrate any electric field that is present in the environment surrounding the reticle and “focus” it onto this region. [0014] The invention involves placing special structures that will be visibly damaged by electric fields at suitable locations within the gap between the guard ring and the image area of the reticle. These structures are likely to become damaged more readily than the features in the image area of the reticle, owing to their position in the most field-sensitive area of the reticle. [0015] Regular reticle inspections for the effects of electric field exposure can be carried out by looking at these sensor structures rather than by inspecting the entire image area. Any deviation of these sensor patterns from normal will indicate that the reticle has been exposed to a hazardous electric field and should be inspected thoroughly to determine that all the functional reticle features are still within specification. [0016] The invention provides a reticle comprising: an image area having one or more electrically conductive portions susceptible to damage by an electric field; and an electrical field sensor feature, the sensor feature adapted to be at least as susceptible to being altered by the electric field as the electrically conductive portions of the image area, the sensor feature being located in a position which is more readily viewable to show alteration than the electrically conductive portions of the image area. Preferably, the reticle further comprises a guard ring comprising an electrically conductive element located around the periphery of the image area and separated from the image area by an insulating gully, and wherein the damage sensor feature is located in the gully between the image area and the guard ring. Preferably, the guard ring substantially encloses the image area in a two-dimensional plane. Preferably, the guard ring comprises chrome. Preferably, the sensor feature comprises one or more electrically isolated structures oriented to provide sensitivity to the direction of the electric field. Preferably, the sensor feature comprises a target structure of standardized shape and size that may be used for automated inspection in a reticle inspection tool. Preferably, a plurality of the sensor features are disposed around the periphery of the image area to provide the ability to detect and differentiate electric fields impinging on the reticle from a plurality of directions. Preferably, the sensor features are placed in sufficient quantity to adequately sense electric fields impinging on the reticle from various directions, while also being of a minimum quantity to maximize the effect of the electric field on each sensor feature. Preferably, the one or more sensor features are designed to amplify the potential gradient or electric field in the region of the sensor feature. [0017] The invention also provides a method for monitoring the condition of a reticle having an image area, the method comprising: providing one or more sensor features that are capable of being altered by the presence of an electric field, the sensor features being separate from the image area; and detecting whether any of the one or more of the sensor features have been altered. Preferably, the method further comprises, upon detecting the alteration, inspecting the image area for electric-field-induced damage. Preferably, the method further includes recording the inspection result in an inspection log. Preferably, the method further includes amplifying the potential gradient or electric field at the position of the one or more sensor features. Preferably, the method further includes recording the result of the detecting in an inspection log. Preferably, the method further comprises repeating the detecting after a prescribed period of use of the reticle. Preferably, the method further comprises inspecting the sensor features to determine their condition before use. [0018] In another aspect, the invention provides a computer readable medium including a software or firmware program having instructions for inspecting a reticle, the reticle including an image, the program including instructions for: detecting the alteration of one or more electrical field sensor features on the reticle, the electrical field sensor features being separate from the image; and upon detecting the alteration of the one or more sensor features, providing instructions for inspecting the image area for electric-field-induced damage. Preferably, the instructions further include instructions for inspecting the reticle to establish the condition of the one or more sensor features before use. Preferably, the instructions further include instructions for repeating the detecting after a prescribed period of use of the reticle. [0019] In yet another aspect, the invention provides a computer readable medium including a software or firmware program having instructions for inspecting a reticle, the reticle including an image, the program including instructions for detecting whether one or more of electrical field sensor features have been altered, the electric field sensor features being separate from the image; and recording the result of the detecting in an inspection log. [0020] Remarkably, the invention provides inspection apparatus and processes in which ESD and EFM damage can be detected more effectively and at the same time is faster and more economical than the prior art. Numerous other features, objects, and advantages of the invention will become apparent from the following description when read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0021] FIG. 1 is a perspective view of a prior art reticle; [0022] FIG. 2 is a plan view of a reticle according to the invention; [0023] FIG. 3A is a cross-sectional view of the reticle of FIG. 2 taken through the line 3 A- 3 A of FIG. 2 ; [0024] FIG. 3B is a cross-sectional view of the reticle of FIG. 2 taken through the line 3 B- 3 B of FIG. 2 ; [0025] FIG. 4 is a plan view showing a detail of an alternative preferred embodiment according to the invention; and [0026] FIG. 5 is a flow chart showing a preferred embodiment of an inspection process according to the invention. DETAILED DESCRIPTION OF THE INVENTION [0027] A standard reticle structure characteristic of the prior art is shown in perspective view in FIG. 1 . The insulating substrate 101 is coated on one of its major surfaces with a conductive light-absorbing film 102 into which is etched a pattern, herein referred to as the image area 103 . The image area 103 is surrounded by a clear space 104 , herein referred to as the gully, which separates the image area 103 from the continuous border, herein referred to as the guard ring 105 . Film 102 preferably is made by a deposition process, which is known in the art. All the features 103 , 104 , and 105 are made by etching the film 102 during manufacture of the reticle. Sometimes, the conductive light-absorbing film is coated with an anti-reflection layer to improve optical performance in the lithography tool. This does not affect the interaction of the reticle with electric fields. [0028] An embodiment of the invention is shown in plan view in FIG. 2 . One or more electric field sensing features 201 are placed in gully 104 between the image area 103 and the guard ring 105 . These features preferably are defined on the surface of the reticle when the mask pattern is written and are created when the film 102 is etched to form features 103 , 104 , and 105 . Since an electric field that penetrates the reticle may come from any direction, preferably, multiple sensor structures are positioned around the periphery of the image area 103 . Preferably, the number of structures so placed is sufficient to adequately sense all incident electric field directions relative to the reticle, but is kept to a minimum so that induced current passing through and between the sensing features 201 is not averaged over a large number of the sites, which would reduce the magnitude of the effect on each individual feature. That is, the effect of an electric field is maximized on as few as possible of the sensing features 201 , thereby maximizing the visibility of changes to the features with the lowest possible strength of electric field interacting with the reticle. [0029] The operation of the sensing features is explained in reference to FIGS. 3A and 3B . FIG. 3A represents a cross-section through the reticle at the place indicated by the dotted line 3 A- 3 A in FIG. 2 . Dashed line 301 represents the potential gradient or the electric field that would be present across the gully 104 when the reticle is placed into an environment containing an electric field. The direction of the field is arbitrary. With no features in the gully 104 , the potential gradient and the electric field across the gully is represented by the gradient of the graph 301 in the lower section of the figure. Features 103 and 105 are at different induced potentials due to the presence of the external electric field. When the sensing feature 201 is placed into the gully in such a situation, as shown in FIG. 3B , it will adopt a potential which is intermediate between the potentials of 103 and 105 . Thus, the potential gradient or electric field strength 304 at the gully region 104 , which is already the most sensitive area of the reticle, is amplified by the presence of the sensing features. If the field strength and induced potential differences within the image area 103 are below the level where significant changes are caused to the reticle image features, this amplification of the same electric field by the sensing features in the gully may render them liable to change. Hence, they may indicate the existence of a hazard in the reticle handling environment before significant damage is caused to the reticle image area 103 . [0030] The sensing feature 201 in FIGS. 2 and 3 contains at least one conductive body 201 which partially spans the gully 104 between the image area 103 and the guard ring 105 . However, other variants of the sensing feature are possible. Such an alternative preferred embodiment is shown in FIG. 4 . In this embodiment, the sensing feature 400 comprises four parts, 401 , 402 , 403 , and 404 , spatially oriented so that they will respond differently to environmental electric fields passing at different angles across the gully 104 . The central intersection 401 of these four structures forms a convenient target for use in an automated inspection microscope. Such an image can be automatically inspected and compared against the previous inspection image stored in a database. Any variation in the appearance of this feature will indicate that the reticle has been exposed to an electric field, and the image area 103 should be inspected carefully for possible damage. [0031] A flow chart illustrating an example of the method 500 that would apply to this form of inspection regime is given in FIG. 5 . At 502 , the reticle is inspected to establish its condition, and particularly the condition of the sensing features, before use. A determination of whether the sensing features are damaged is made at 504 and, if there is no damage, the result is recorded in a reticle log and the reticle is used for a prescribed period and the process returns to 504 where it is redetermined if the features are damaged. If damage is found in the sensing features at any point, the process proceeds to 510 . The inspection images are recorded and at 516 an investigation is initiated to identify and correct the source of risk The pattern area is also inspected for damage at 510 . If damage to the image features is detected at 520 , the reticle is directed to 530 for repair or scrap. If the image features are not damaged, the inspection result is recorded in the reticle log at 522 , the reticle is then used for a prescribed period, and then reinspected. The prescribed period of use may be set for a shorter period when, for example, there have been recent changes to a manufacturing process, and then for a longer period once the problem areas have been worked out in a manufacturing process. If a change in the image features is found at 526 , the program returns to 510 and the cycle is repeated. If there is no change in the sensing features, the program returns to 522 where it is again used and reinspected. In this way, a rapid assessment may be conducted of the condition of a reticle with regard to any electrostatic hazard it may have experienced since its last inspection. Minimal data processing is required, with reduction of the need to regularly inspect the entire image area of the reticle. Hence, the process will occupy a minimum amount of inspection tool time and operator workload. At the same time, it is more sensitive to damage, since damage to the sensing areas is easier to detect. Since the same sensing features may be printed on all reticles, the process can be automated and the above processes can be incorporated into software instructions in a computer program on a computer readable medium. [0032] There has been described apparatus and methods for quickly and effectively determining if a reticle has suffered ESD or EFM damage. It should be understood that the particular embodiments shown in the drawings and described within this specification are for purposes of example and should not be construed to limit the invention which will be described in the claims below. Further, it is evident that those skilled in the art may now make numerous uses and modifications of the specific embodiment described, without departing from the inventive concepts. For example, it is also evident that the steps recited may, in some instances, be performed in a different order; or equivalent structures and processes may be substituted for the various structures and processes described; or a variety of different precursors may be used. Consequently, the invention is to be construed as embracing each and every novel feature and novel combination of features present in and/or possessed by the reticle protection and damage determination processes, the devices to perform such functions, and electronic device manufacturing methods described.
A reticle includes an image area having one or more electrically conductive portions susceptible to damage by an electric field and an electric field sensor feature, the sensor feature adapted to be at least as susceptible to being altered by the electric field as the electrically conductive portions of the image area, the sensor feature being located in a position which is more readily viewable to show alteration than the electrically conductive portions of the image area.
Summarize the key points of the given patent document.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application Ser.", "No. 60/782,928 filed Mar. 16, 2006, which application is hereby incorporated by reference to the same extent as though fully disclosed herein.", "FIELD OF INVENTION [0002] This application relates to the field of photomasks, referred to in the trade as reticles, used in the production of semiconductor devices, and more particularly to such reticles that are sensitive to electrical fields.", "BACKGROUND OF THE INVENTION [0003] Transmission photomasks (reticles) used in the production of semiconductor devices are often constructed using conductive metallic films (for example, chromium), or other films, such as MoSiON, deposited onto a transparent substrate, such as quartz.", "A pattern is etched into this film and then is projected by photo-reduction onto a semiconductor wafer coated with a photosensitive layer.", "By this means, a replica of the pattern on the reticle is produced in the film on the semiconductor wafer, which replica is greatly reduced in size.", "Through further and repeated processing of the wafer, a three-dimensional microcircuit is built up.", "[0004] Such reticles may contain a multitude of isolated conductive features supported on an electrically insulating substrate.", "These conductive features, which together make up the pattern that is to be projected onto the wafer, can have differing electrical potentials induced on them if the reticle is placed into an electric field.", "The presence of differing electric potentials on neighboring conductive features can cause electrical discharge between the features in a process that is referred to as field-induced electrostatic discharge (ESD).", "Furthermore, the features may also be damaged by such induced potentials even when an electrostatic discharge does not take place in a process referred to as electric field-induced material migration (EFM).", "[0005] The degree of damage that a reticle will suffer as a result of such exposure to an electric field is difficult to predict, since the induction process is dependent upon the detailed structure of the pattern on the reticle, its orientation with respect to the electric field, and its proximity to surrounding objects which might perturb the electric field and concentrate such field through certain areas of the pattern.", "This makes it difficult to define how frequently a reticle should be inspected for damage in normal use to prevent production of defective wafers.", "Furthermore, any electric field-induced damage that is sustained by a reticle maybe subtle, highly localized, and difficult to detect during routine reticle inspections.", "Even though the damage may not be detected in the reticle inspection tool, it may affect the lithographic process.", "[0006] The damage to the reticle may cause the image projected on the wafer to deviate from that which is expected and which is required for correct functioning of the finished semiconductor device.", "This is referred to as Critical Dimension (CD) deviation.", "When a reticle becomes damaged in such a way, defective devices can be produced;", "and this may not be discovered until the complete device has been built and is tested.", "Discovery of defects at this late stage in the production process results in significant financial losses to the semiconductor industry.", "[0007] Electrostatic damage to reticles has been such a prevalent factor in semiconductor production for many years that various novel approaches have been suggested for countering it.", "In 1984, U.S. Pat. No. 4,440,841 described one of the first methods for making a reticle with an integral conductive layer capable of dissipating electrostatic charge.", "In 1985, JP Patent No. 60,222,856 described a means of connecting the various mask elements with filamentary conductive lines to avoid potential differences between them.", "Since those first two approaches, many variants involving conductive coatings, featuring interconnects, and charge dissipating structures have been proposed (e.g., JP Patent No. 62,293,244 (1987);", "U.S. Pat. No. 5,798,192 (1998);", "U.S. Pat. No. 5,989,754 (1999);", "KR Patent No. 196,585Y (2000);", "U.S. Pat. No. 6,180,291 (2001);", "TW Patent No. 441,071 (2001);", "KR Patent Publication No. 2001/057347 (2001);", "U.S. Pat. No. 6,291,114 (2001);", "U.S. Pat. No. 6,309,781 (2001);", "JP Patent Publication No. 2002/055438 (2002);", "US Patent Publication No. 2002/0115001(2002);", "U.S. Pat. No. 6,440,617 (2002);", "U.S. Pat. No. 6,569,576 B1 (2003);", "TW Patent No. 543,178 (2003);", "KR Patent Publication No. 2003/085946 (2003);", "JP Patent Publication No. 2004/061884 (2004);", "US Patent Publication No. 2004/076834 (2004);", "and U.S. Pat. No. 6,803,156 (2004)).", "These solutions increase the complexity and cost of reticle manufacture, plus they add process steps which can introduce defects or inhomogeneity to the reticle.", "Coatings may delaminate, or they may be easily damaged during handling and reticle cleaning.", "Furthermore, some of the coatings that have been suggested may degrade due to exposure to energetic UV light that is used in today's leading edge lithography systems;", "hence, their transparency may alter with time.", "All of these potential problems probably explain why such solutions are not in widespread use today and why reticle ESD damage continues to be a problem in the semiconductor manufacturing industry.", "[0008] If the reticle itself cannot be made inherently ESD protected, an alternative solution is to enclose the reticle inside a conductive container, which will provide ESD protection by shielding the reticle from electric fields.", "Such a solution is described in PCT Publication No. WO 2004/032208.", "This will protect the reticle while it is inside the container;", "but semiconductor manufacturing requires the reticle to be moved outside the container on many occasions, during which time the reticle might be exposed to electric fields.", "Since electric field exposure during normal use of the reticle may gradually change the image on the reticle in a way that is detrimental to the final device that is being manufactured, it is important to be able to monitor a reticle's exposure to electric fields.", "[0009] US Patent Publication No. 2003/0052691 describes a portable, compact sensor device that is capable of detecting the ESD events in a semiconductor manufacturing facility through their radio emissions.", "This has been suggested as a means of detecting ESD events in reticles by placing a sensor in the reticle handling environment or in/on the reticle carrier.", "However, such RF pulse sensing devices can only report the ESD event after the reticle is damaged, and EFM cannot be detected since there is no electrical discharge event.", "They also are likely to be sensitive to false alarms, owing to the highly charged nature of a semiconductor manufacturing facility.", "[0010] A more effective and reliable means is required for routinely sensing whether a reticle has been exposed to an electric field.", "Such a sensor that could warn of a hazardous exposure before the reticle itself becomes damaged would be very desirable.", "BRIEF SUMMARY OF THE INVENTION [0011] The present invention advances the reticle art by solving one or more of the above problems.", "[0012] The coupling of an electric field through a reticle is strongly affected by the presence of a continuous conductive border on the substrate.", "Such a border normally is present to prevent unwanted light from passing into the optical system of the lithography tool that is being used to print the reticle image onto the semiconductor wafer.", "This border sometimes is referred to as a “guard ring”;", "and it may also contain other structures such as alignment marks, bar codes, and human readable codes for identification of the reticle.", "It is separated from the image area by a clear space, and this electrically isolates the features in the image area from the guard ring.", "[0013] Owing to the nature of the interaction of the guard ring with any electric field that impinges on the reticle, the electric field is perturbed such that its direction and strength are altered.", "A feature of the invention is that this interaction preferably is such that the field strength within the plane of the reticle is greatest in the region of the image closest to the guard ring.", "Thus, any electric-field-induced damage that the reticle suffers should be most severe in these areas.", "Thus, the guard ring may concentrate any electric field that is present in the environment surrounding the reticle and “focus”", "it onto this region.", "[0014] The invention involves placing special structures that will be visibly damaged by electric fields at suitable locations within the gap between the guard ring and the image area of the reticle.", "These structures are likely to become damaged more readily than the features in the image area of the reticle, owing to their position in the most field-sensitive area of the reticle.", "[0015] Regular reticle inspections for the effects of electric field exposure can be carried out by looking at these sensor structures rather than by inspecting the entire image area.", "Any deviation of these sensor patterns from normal will indicate that the reticle has been exposed to a hazardous electric field and should be inspected thoroughly to determine that all the functional reticle features are still within specification.", "[0016] The invention provides a reticle comprising: an image area having one or more electrically conductive portions susceptible to damage by an electric field;", "and an electrical field sensor feature, the sensor feature adapted to be at least as susceptible to being altered by the electric field as the electrically conductive portions of the image area, the sensor feature being located in a position which is more readily viewable to show alteration than the electrically conductive portions of the image area.", "Preferably, the reticle further comprises a guard ring comprising an electrically conductive element located around the periphery of the image area and separated from the image area by an insulating gully, and wherein the damage sensor feature is located in the gully between the image area and the guard ring.", "Preferably, the guard ring substantially encloses the image area in a two-dimensional plane.", "Preferably, the guard ring comprises chrome.", "Preferably, the sensor feature comprises one or more electrically isolated structures oriented to provide sensitivity to the direction of the electric field.", "Preferably, the sensor feature comprises a target structure of standardized shape and size that may be used for automated inspection in a reticle inspection tool.", "Preferably, a plurality of the sensor features are disposed around the periphery of the image area to provide the ability to detect and differentiate electric fields impinging on the reticle from a plurality of directions.", "Preferably, the sensor features are placed in sufficient quantity to adequately sense electric fields impinging on the reticle from various directions, while also being of a minimum quantity to maximize the effect of the electric field on each sensor feature.", "Preferably, the one or more sensor features are designed to amplify the potential gradient or electric field in the region of the sensor feature.", "[0017] The invention also provides a method for monitoring the condition of a reticle having an image area, the method comprising: providing one or more sensor features that are capable of being altered by the presence of an electric field, the sensor features being separate from the image area;", "and detecting whether any of the one or more of the sensor features have been altered.", "Preferably, the method further comprises, upon detecting the alteration, inspecting the image area for electric-field-induced damage.", "Preferably, the method further includes recording the inspection result in an inspection log.", "Preferably, the method further includes amplifying the potential gradient or electric field at the position of the one or more sensor features.", "Preferably, the method further includes recording the result of the detecting in an inspection log.", "Preferably, the method further comprises repeating the detecting after a prescribed period of use of the reticle.", "Preferably, the method further comprises inspecting the sensor features to determine their condition before use.", "[0018] In another aspect, the invention provides a computer readable medium including a software or firmware program having instructions for inspecting a reticle, the reticle including an image, the program including instructions for: detecting the alteration of one or more electrical field sensor features on the reticle, the electrical field sensor features being separate from the image;", "and upon detecting the alteration of the one or more sensor features, providing instructions for inspecting the image area for electric-field-induced damage.", "Preferably, the instructions further include instructions for inspecting the reticle to establish the condition of the one or more sensor features before use.", "Preferably, the instructions further include instructions for repeating the detecting after a prescribed period of use of the reticle.", "[0019] In yet another aspect, the invention provides a computer readable medium including a software or firmware program having instructions for inspecting a reticle, the reticle including an image, the program including instructions for detecting whether one or more of electrical field sensor features have been altered, the electric field sensor features being separate from the image;", "and recording the result of the detecting in an inspection log.", "[0020] Remarkably, the invention provides inspection apparatus and processes in which ESD and EFM damage can be detected more effectively and at the same time is faster and more economical than the prior art.", "Numerous other features, objects, and advantages of the invention will become apparent from the following description when read in conjunction with the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS [0021] FIG. 1 is a perspective view of a prior art reticle;", "[0022] FIG. 2 is a plan view of a reticle according to the invention;", "[0023] FIG. 3A is a cross-sectional view of the reticle of FIG. 2 taken through the line 3 A- 3 A of FIG. 2 ;", "[0024] FIG. 3B is a cross-sectional view of the reticle of FIG. 2 taken through the line 3 B- 3 B of FIG. 2 ;", "[0025] FIG. 4 is a plan view showing a detail of an alternative preferred embodiment according to the invention;", "and [0026] FIG. 5 is a flow chart showing a preferred embodiment of an inspection process according to the invention.", "DETAILED DESCRIPTION OF THE INVENTION [0027] A standard reticle structure characteristic of the prior art is shown in perspective view in FIG. 1 .", "The insulating substrate 101 is coated on one of its major surfaces with a conductive light-absorbing film 102 into which is etched a pattern, herein referred to as the image area 103 .", "The image area 103 is surrounded by a clear space 104 , herein referred to as the gully, which separates the image area 103 from the continuous border, herein referred to as the guard ring 105 .", "Film 102 preferably is made by a deposition process, which is known in the art.", "All the features 103 , 104 , and 105 are made by etching the film 102 during manufacture of the reticle.", "Sometimes, the conductive light-absorbing film is coated with an anti-reflection layer to improve optical performance in the lithography tool.", "This does not affect the interaction of the reticle with electric fields.", "[0028] An embodiment of the invention is shown in plan view in FIG. 2 .", "One or more electric field sensing features 201 are placed in gully 104 between the image area 103 and the guard ring 105 .", "These features preferably are defined on the surface of the reticle when the mask pattern is written and are created when the film 102 is etched to form features 103 , 104 , and 105 .", "Since an electric field that penetrates the reticle may come from any direction, preferably, multiple sensor structures are positioned around the periphery of the image area 103 .", "Preferably, the number of structures so placed is sufficient to adequately sense all incident electric field directions relative to the reticle, but is kept to a minimum so that induced current passing through and between the sensing features 201 is not averaged over a large number of the sites, which would reduce the magnitude of the effect on each individual feature.", "That is, the effect of an electric field is maximized on as few as possible of the sensing features 201 , thereby maximizing the visibility of changes to the features with the lowest possible strength of electric field interacting with the reticle.", "[0029] The operation of the sensing features is explained in reference to FIGS. 3A and 3B .", "FIG. 3A represents a cross-section through the reticle at the place indicated by the dotted line 3 A- 3 A in FIG. 2 .", "Dashed line 301 represents the potential gradient or the electric field that would be present across the gully 104 when the reticle is placed into an environment containing an electric field.", "The direction of the field is arbitrary.", "With no features in the gully 104 , the potential gradient and the electric field across the gully is represented by the gradient of the graph 301 in the lower section of the figure.", "Features 103 and 105 are at different induced potentials due to the presence of the external electric field.", "When the sensing feature 201 is placed into the gully in such a situation, as shown in FIG. 3B , it will adopt a potential which is intermediate between the potentials of 103 and 105 .", "Thus, the potential gradient or electric field strength 304 at the gully region 104 , which is already the most sensitive area of the reticle, is amplified by the presence of the sensing features.", "If the field strength and induced potential differences within the image area 103 are below the level where significant changes are caused to the reticle image features, this amplification of the same electric field by the sensing features in the gully may render them liable to change.", "Hence, they may indicate the existence of a hazard in the reticle handling environment before significant damage is caused to the reticle image area 103 .", "[0030] The sensing feature 201 in FIGS. 2 and 3 contains at least one conductive body 201 which partially spans the gully 104 between the image area 103 and the guard ring 105 .", "However, other variants of the sensing feature are possible.", "Such an alternative preferred embodiment is shown in FIG. 4 .", "In this embodiment, the sensing feature 400 comprises four parts, 401 , 402 , 403 , and 404 , spatially oriented so that they will respond differently to environmental electric fields passing at different angles across the gully 104 .", "The central intersection 401 of these four structures forms a convenient target for use in an automated inspection microscope.", "Such an image can be automatically inspected and compared against the previous inspection image stored in a database.", "Any variation in the appearance of this feature will indicate that the reticle has been exposed to an electric field, and the image area 103 should be inspected carefully for possible damage.", "[0031] A flow chart illustrating an example of the method 500 that would apply to this form of inspection regime is given in FIG. 5 .", "At 502 , the reticle is inspected to establish its condition, and particularly the condition of the sensing features, before use.", "A determination of whether the sensing features are damaged is made at 504 and, if there is no damage, the result is recorded in a reticle log and the reticle is used for a prescribed period and the process returns to 504 where it is redetermined if the features are damaged.", "If damage is found in the sensing features at any point, the process proceeds to 510 .", "The inspection images are recorded and at 516 an investigation is initiated to identify and correct the source of risk The pattern area is also inspected for damage at 510 .", "If damage to the image features is detected at 520 , the reticle is directed to 530 for repair or scrap.", "If the image features are not damaged, the inspection result is recorded in the reticle log at 522 , the reticle is then used for a prescribed period, and then reinspected.", "The prescribed period of use may be set for a shorter period when, for example, there have been recent changes to a manufacturing process, and then for a longer period once the problem areas have been worked out in a manufacturing process.", "If a change in the image features is found at 526 , the program returns to 510 and the cycle is repeated.", "If there is no change in the sensing features, the program returns to 522 where it is again used and reinspected.", "In this way, a rapid assessment may be conducted of the condition of a reticle with regard to any electrostatic hazard it may have experienced since its last inspection.", "Minimal data processing is required, with reduction of the need to regularly inspect the entire image area of the reticle.", "Hence, the process will occupy a minimum amount of inspection tool time and operator workload.", "At the same time, it is more sensitive to damage, since damage to the sensing areas is easier to detect.", "Since the same sensing features may be printed on all reticles, the process can be automated and the above processes can be incorporated into software instructions in a computer program on a computer readable medium.", "[0032] There has been described apparatus and methods for quickly and effectively determining if a reticle has suffered ESD or EFM damage.", "It should be understood that the particular embodiments shown in the drawings and described within this specification are for purposes of example and should not be construed to limit the invention which will be described in the claims below.", "Further, it is evident that those skilled in the art may now make numerous uses and modifications of the specific embodiment described, without departing from the inventive concepts.", "For example, it is also evident that the steps recited may, in some instances, be performed in a different order;", "or equivalent structures and processes may be substituted for the various structures and processes described;", "or a variety of different precursors may be used.", "Consequently, the invention is to be construed as embracing each and every novel feature and novel combination of features present in and/or possessed by the reticle protection and damage determination processes, the devices to perform such functions, and electronic device manufacturing methods described." ]
BACKGROUND OF THE INVENTION This invention relates to a seal assembly disposed between and within two stationary members employed on an engine and having a common passageway formed therein to communicate coolant therethrough. Cooling systems as used upon internal combustion engines have ,several passages for coolant flow. Often some of the passages cannot be efficiently contained completely within the major members that make up the engine, such as the block, cylinder heads, front cover assembly, and manifolds, and must be routed externally. These external passages usually consist of hoses, single piece tube assemblies with O-rings or other seals, press in rubber seals, expandable rubber seals, and other devices which form a static seal between adjacent members of an engine. An additional function of some sealing apparatus that form a passage is introducing a restriction in a coolant passage to control flow. Nearly all engines that use liquid for cooling purposes require a device or selection of passage sizing which restricts the flow of coolant to avoid overcooling or reduce cavitation. Selective sizing of the of the seal's bore will influence the volume of coolant which may pass through it and the adjoining member. When engines are originally manufactured, their design is put forth which anticipates the use of one or more of the seal types mentioned above. Few different designs, if any, are interchangeable with each other during assembly, maintenance, or repair of an engine. Thus, particularly in the case of a single piece tubular device with O-ring seals, if leakage occurs. at least one of the major engine members must be removed and replaced upon the engine in order to replace the tube or O-ring seals. Even though the original tubular units can be cut or broken out of their original position, available replacement parts duplicate the original single piece design and require removal and replacement of one or more major engine members. Although several types of water seals exist for various purposes, none are able to efficiently and directly replace the above mentioned single piece tubular design which seals and is positioned within existing coolant passage bores in the adjacent engine members. Two prior designs are U.S. Pat. No. 3,603,618 to Stratton (1971) and an improvement on same, U.S. Pat. No. 4,234,198 to Marten, Smith (1980) both disclose a single elastomeric seal with ferrule assembly which seals directly upon the face of the members. Both designs have an inside diameter which is as large or larger than the bore of the passage within the members which they form a passage with. These designs require a means external of the coolant passages fbr mounting and alignment. As mentioned in their description and claims, both of these seal designs utilize notches, annular cut-outs, grooves, or bosses, for alignment and mounting purposes, which require original engine manufacturing that anticipates their use. Since both of these prior designs seal directly against the face of the engine members, it is required that there be a substantial radially flat area machined upon the face of each member of the engine to provide an accommodating surface for the elastomeric seal. Another deficiency in these designs is that the elastomeric seal does not have sufficient volume of resilient material to maintain outwardly pressure and static seal over an extended time period. This weakness is due to heating and cooling cycles common with internal combustion engines, which tend to stiffen and eventually cause slight shrinkage to these types of material. Evidence of this is U.S. Pat. No. 4,234,198, as identified above, which attempts to add resilient material and increase the clamping forces. Mounting and space limitations limit the range, usefulness, and reliability of these prior designs. These prior designs would be prohibited where there are substantial contours, space limitations, or lack of a substantially flat machined surface on the radially extending face surrounding the coolant passages of each adjacent member of the engine. Another prior design, U.S. Pat. No. 4,400,018 to Abbes, Rouaud, Forges, and de Villepoix (1983) discloses a seal assembly for joining two opposing pipe ends. The inside diameter of the seal assembly is as large or larger than the bore of the pipes that it connects. The two opposing flanges are flat except for a cradle for the extensible member to reside upon. The two opposing flanges must also be welded onto the end of each pipe. O-rings are used between the face of each flange and the extensible members. The assembly requires two separate extensible members with conical shaped faces. A two piece moveable member, with a double conical shape is wedged in between the extensible members and presses against the latter mentioned conical faces. The moveable member also bears against the rear faces of the radial flanges to prevent the pipes from moving apart. No part of this invention resides within the passages of the members or in this case pipes. Mounting relies on the front and back sides of external, flat, welded on flanges. All sealing is accomplished with two separate O-rings which each seal against three surfaces. The internal diameter of the tubular member is substantially the same diameter as the corresponding pipes. This seal assembly requires a multiple of flat radial surfaces for mounting means. The extensible members are of rigid material and do not serve to form the seal between the pipes. Sealing is accomplished by pressure exerted upon the. O-rings by the extensible member to form sealing contact between the flanges and the tubular member. It would be nearly impossible to utilize this seal assembly between rigidly mounted members of an engine which do not have several inches of space between them and which do not have a tubular projection with flanges incorporated upon them during their manufacture. Another prior art example is U.S. Pat. No. 4,417,735 to Heisler (1983) reveals a sealing device disposed between adjacent members of an engine. This design also has an inside diameter as large or larger than the bore of the passage in the members which it seals. A centering bead exists on one of the members to provide a means of locating the seal assembly. Clamping upon a trapezoidal shape is used to cause expansion outwardly against the members. This is, a rigid design with resilient material being used only in the form of gasketing applied to the outer surfaces. The sealing and mounting of this seal assembly is completely dependant on the protruding surfaces of the members being precisely machined to form a corresponding mechanical fit. This design allows a component such as a manifold to be removed without disturbing other members. However it does not allow for the seal itself to be installed or removed alone. The seal assembly must be placed upon one of the engine components while one of the component is being installed. Again, for reasons similar to those mentioned above, this seal assembly would be nearly impossible to use between rigidly mounted adjacent members of an engine. None of these prior art examples are capable of mounting within the bore of existing passages, or have any provisions for control of coolant flow. Further, none are capable of sealing where there are no special machined surfaces or other devices provided upon the face of each adjacent member. BRIEF SUMMARY OF THE INVENTION An object of this invention is to provide a more serviceable seal assembly of the above type, particularly adapted for applications in the cooling system of internal combustion engines. The seal assembly comprises an annular ferrule, an elastomeric seal circumferentially disposed thereabout and a pair of annular mounting rings. The annular mounting rings provide a radial surface to engage with the elastomeric seal and also extend into and seal within the coolant passage bore of each adjacent member. A clamping means circumferentially surrounds the seal and ferrule to apply a clamping force radially inwardly on the seal to expand the sidewalls thereof into sealing contact with the annular mounting rings. The annular mounting rings may also provide for control of coolant flow by selection of bore sizing. OBJECTS AND ADVANTAGES Accordingly, several objects and advantages of the present invention are; a) to provide a seal assembly which can easily be installed without removing any major engine members such as a cylinder head or front cover assembly; b) to provide a seal assembly which can easily be installed by hand without any additional machining, welding or fabrication; c) to provide a seal assembly which mounts and seals within opposing passages employed on members of an engine and which are separated from each other by a gap which is at least wide enough to install the various parts of the invention; d) to provide a seal assembly which utilizes existing bores within the members to provide all necessary mounting and alignment of the various parts of the seal assembly; e) to provide a seal assembly with a low overall profile which is tolerant of substantial contours, space limitations, or lack of a substantial radially flat area, which may be on or near the face of one or both adjacent members of the engine; f) to provide a seal assembly which can be more easily serviced when necessary to repair leaks or perform other maintenance; g) to provide a seal assembly which by it's construction is mostly reusable; h) to provide a seal assembly which by selective sizing of it's bore can be used to control the volume of coolant flow; i) to provide a seal assembly which no longer causes many other engine parts such as gaskets, seals, coolant, oil and filters, and other used but serviceable parts, which may not be at the end of their useful service life, to be replaced prematurely; j) to provide a seal assembly which is at least as reliable as prior art and has sufficient volume and shape of resilient material to withstand aging which is inherent with the frequent heating and cooling cycles common to internal combustion engines, thus not needing periodic adjusting of the clamping means or other undesirable maintenance. Further objects and advantages are to provide a seal assembly which can be utilized nearly anytime or anywhere an engine may be, including when a leak occurs on-the-job, avoiding the need for towing or more expensive damage and repairs due to loss of coolant. Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a sectioned isometric view of a seal assembly embodying this invention, shown disposed between a pair of adjacent members to form a static seal within a common passageway formed therein; FIG. 2 is a view similar to FIG. 1, but illustrating the seal assembly in it's installed condition shown within and between sectioned members; FIG. 3 is a cross section exploded view of the parts of the seal, shown in the direction of arrows II—II in FIGS. 1 and 2, but not including the clamp which is of standard design; FIG. 4 is a cross section view illustrating the seal assembly, shown in the direction of arrows II—II in FIGS. 1 and 2 in it's installed condition between a pair of adjacent members to form a static seal within a common passageway formed therein; FIG. 5 is an expanded view showing the various parts of the seal assembly, but not showing the clamp and O-rings which are of standard design. REFERENCE NUMERALS 3 elastomeric seal 4 O-ring 5 annular mounting ring 6 clamp 7 ferrule 8 coolant passage 9 outwardly flange 10 flexible strap 11 member 12 seal bore 13 step 14 slots 15 step 16 inwardly flange 17 screw 18 O-ring groove 19 outwardly face 20 inwardly face 21 seal assembly DETAILED DESCRIPTION OF THE INVENTION FIG. 1 illustrates a seal assembly 21 disposed between a pair of adjacent members 11 , such as a cylinder head and front cover employed on an internal combustion engine. A common passageway 8 is formed in the members to communicate fluid therebetween, such as water or oil. As will be hereinafter fully described, the seal assembly comprises a pair of anmular mounting rings 5 installed and sealing within the members. An elastomeric seal 3 is placed ard expanded into sealing contact between the annular adapters to provide a static seal therein to prevent the egress of fluid thereby from passageway 8 . Referring to FIGS. 1 and 4, the seal assembly comprises an annular ferrule 7 having an elastomeric seal 3 circumferentially disposed thereabout, a pair of annular mounting rings 5 disposed generally within the stationary members 11 . As shown in FIG. 4, a static seal is formed within each member and the corresponding end of each annular mounting ring by an O-ring seal 4 circumferentially disposed thereabout within a corresponding circumferential groove 18 . However, it should be understood that the location of the O-ring and means other than an O-ring may be used to form a static seal between the annular mounting ring and the member, as is well known by those skilled in the arts relating hereto. As shown in FIG. 3, each annular mounting ring has on it's other end an integral radial flange 16 extending generally inwardly from the annulus. The outwardly face of said inwardly flange provides an area for the elastomeric seal to press and seal against. In applications where control of coolant flow is desired, the inwardly extending flange of each annular mounting ring has a bore 12 which can be selectively sized based on cooling system requirements. The overall length of each annular mounting ring must be less than the gap existing between the stationary members to facilitate installation without removal of either member. The inside diameter of the ferrule 7 is substantially the same as the bore 12 of the annular mounting rings. As shown in FIGS. 3 and 5, preformed into each sidewall of the elastomeric seal 3 and outwardly face of the inwardly flange of the annular mounting rings 5 is a contour in the form of a step 13 and 15 . The step can be defined generally by two different overall cross sectional widths of the elastomeric seal and the radial flange of the annular mounting rings. The step upon each face of the elastomeric seal corresponds with a like but directionally opposite step disposed upon the face of the radial flange of each annular mounting ring to provide a means for alignment. It is desirable for the height of each step disposed upon all described faces be equal to between 5% and 20% of the cross sectional thickness of the elastomeric seal with such height approximating 8%. The preferred diameter of the step 15 as viewed upon the face of the elastomeric seal and radial flange of the annular adapter rings is between 5% and 100% of overall face diameter with such diameter approximating 70%. However it should be understood that any combination of diameter or height of the step, or that nearly any corresponding surface variation may be used for alignment purposes as is well known by those skilled in the arts relating hereto. As shown in FIG. 3, the radial flange 16 of the annular mounting ring 5 viewed in cross section extends mostly radially inwardly from the annulus for the purpose described above. Each annular mounting ring also has a flange 9 extending radially outwardly a short distance. Flange 9 comprises an outwardly face 20 which provides additional area for the elastomeric seal. Said flange also comprises a inwardly face 19 which provides a means to limit the adapter's installed depth into the member. In so doing, outwardly flange serves to counteract the pressure exerted by the elastomeric seal. As shown in all figures, both inwardly and outwardly radially extending flanges upon each annular mounting ring share a generally common radial plane. However it should be understood that other means to limit the depth of insertion of the annular mounting ring into the member may cause the outwardly flange to be on a different plane than that mentioned above or not exist at all as is well known by those skilled in the arts relating hereto. As shown in FIGS. 1 and 4 a clamping means 6 circumferentially surrounds the elastomeric seal 3 for applying a clamping force radially inward on the outer surface of the seal to expand the sidewalls thereof into sealing contact with the annular mounting rings 5 . The clamping means may be of standard design as shown in FIG. 2 comprising a flexible strap 10 having a plurality of slots 14 formed therein to engage the spiraled threads (not shown) of a screw 17 . Thus, selective rotation of the screw in either direction will either contract or expand the strap 10 in a conventional manner. As further shown in FIGS. 1 and 4, installation of the elastomeric seal 3 and tightening of the clamping means 6 serves to hold the annular mounting rings tightly into the confines of the adjacent members and also serves to form a continuous conduit and static seal therewith. The elastomeric seal 3 is preferably composed of a resilient material such as suitably composed rubber based material which will exert the desired sealing forces between parts 5 . However it should be understood that other elastomeric materials may be used for the seal as is well known by those skilled in the arts relating hereto. Ferrule 7 and the annular mounting rings 5 may be composed of brass, composite, or like material which is non-corrosive when subjected to coolants such as water and strong enough to counteract the pressure from the elastomeric seal. The clamping means may be of standard composition which consists of stainless steel. DESCRIPTION OF THE PREFERRED EMBODIMENT Operation and use of the seal assembly is simple and straight forward. The old seal assembly, which the invention is intended to replace, resides in an exposed area between two major engine members. After a portion of the engine coolant has been drained the old seal assembly is removed by cutting it with a small hand or power activated saw to form shorter pieces which can be slid out from the bore of the coolant passage 8 . After removing the pieces, the bores which held the old seal are cleaned of rust and scale usually by sanding or scraping. An O-ring 4 is placed in a locating grove 18 on each annular mounting ring 5 . After applying a suitable lubricant, each annular mounting ring with the accompanying O-ring is slid into the bore of the coolant passage 8 of the adjacent engine members 11 . The support ferrule 7 is placed inside the elastomeric seal 3 and the clamp 6 is placed around the outside. This assembly is then inserted into a centered position between the annular mounting rings. The clamp is then tightened. This completes the installation of the invention. The job is complete when coolant is replaced back into the engine and a final check is made for any leaks. CONCLUSIONS, RAMIFICATIONS, AND SCOPE Accordingly, it can be seen that a seal assembly that can be installed without removal of any major engine members will save a great amount of mechanic's time, equipment down time, and money, when a leak in this area must be repaired. This is brought about by my invention which is at least as reliable as the original equipment seal, fits into existing bores within the coolant passages of two adjacent members, and into an area between the members which have no provisions manufactured onto their outer surface to accommodate other seal types. Because of the profile and nature of mounting, this new seal easily lends itself to applications where control of coolant flow is necessary. Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Various other embodiments and ramifications are possible within it's scope. For example, this invention would be well suited for sealing of opposing pipes, which are otherwise held in place, making a section or sections removable. Likewise, other uses could include a sealed passage between liquid or gas filled vessels or other compartments. This seal design is also capable of working with low to moderate pressures without the use of any circumferential clamping means by proper sizing of the elastomeric seal. Further uses, include a fixed outer ring in place of the clamping means and static sealing arranged by mechanical pressure exerted by the members upon the annular mounting rings to form sealing contact with the elastomeric seal. Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.
This invention relates to a more serviceable seal assembly of the above type, particularly adapted for applications in the cooling systems of internal combustion engines. The seal assembly of this invention comprises an annular ferrule, an elastomeric seal circunferentially disposed thereabout, a pair of annular mounting rings and a clamping device. Tightening of the clamp expands the elastomeric seal outward against the annular mounting rings which are statically sealed within the members of the engine. Selective sizing of the annular mounting rings can be used to control coolant flow. The use of this seal assembly does not require the removal and replacement of members of the engine for installation or servicing.
Identify and summarize the most critical features from the given passage.
[ "BACKGROUND OF THE INVENTION This invention relates to a seal assembly disposed between and within two stationary members employed on an engine and having a common passageway formed therein to communicate coolant therethrough.", "Cooling systems as used upon internal combustion engines have ,several passages for coolant flow.", "Often some of the passages cannot be efficiently contained completely within the major members that make up the engine, such as the block, cylinder heads, front cover assembly, and manifolds, and must be routed externally.", "These external passages usually consist of hoses, single piece tube assemblies with O-rings or other seals, press in rubber seals, expandable rubber seals, and other devices which form a static seal between adjacent members of an engine.", "An additional function of some sealing apparatus that form a passage is introducing a restriction in a coolant passage to control flow.", "Nearly all engines that use liquid for cooling purposes require a device or selection of passage sizing which restricts the flow of coolant to avoid overcooling or reduce cavitation.", "Selective sizing of the of the seal's bore will influence the volume of coolant which may pass through it and the adjoining member.", "When engines are originally manufactured, their design is put forth which anticipates the use of one or more of the seal types mentioned above.", "Few different designs, if any, are interchangeable with each other during assembly, maintenance, or repair of an engine.", "Thus, particularly in the case of a single piece tubular device with O-ring seals, if leakage occurs.", "at least one of the major engine members must be removed and replaced upon the engine in order to replace the tube or O-ring seals.", "Even though the original tubular units can be cut or broken out of their original position, available replacement parts duplicate the original single piece design and require removal and replacement of one or more major engine members.", "Although several types of water seals exist for various purposes, none are able to efficiently and directly replace the above mentioned single piece tubular design which seals and is positioned within existing coolant passage bores in the adjacent engine members.", "Two prior designs are U.S. Pat. No. 3,603,618 to Stratton (1971) and an improvement on same, U.S. Pat. No. 4,234,198 to Marten, Smith (1980) both disclose a single elastomeric seal with ferrule assembly which seals directly upon the face of the members.", "Both designs have an inside diameter which is as large or larger than the bore of the passage within the members which they form a passage with.", "These designs require a means external of the coolant passages fbr mounting and alignment.", "As mentioned in their description and claims, both of these seal designs utilize notches, annular cut-outs, grooves, or bosses, for alignment and mounting purposes, which require original engine manufacturing that anticipates their use.", "Since both of these prior designs seal directly against the face of the engine members, it is required that there be a substantial radially flat area machined upon the face of each member of the engine to provide an accommodating surface for the elastomeric seal.", "Another deficiency in these designs is that the elastomeric seal does not have sufficient volume of resilient material to maintain outwardly pressure and static seal over an extended time period.", "This weakness is due to heating and cooling cycles common with internal combustion engines, which tend to stiffen and eventually cause slight shrinkage to these types of material.", "Evidence of this is U.S. Pat. No. 4,234,198, as identified above, which attempts to add resilient material and increase the clamping forces.", "Mounting and space limitations limit the range, usefulness, and reliability of these prior designs.", "These prior designs would be prohibited where there are substantial contours, space limitations, or lack of a substantially flat machined surface on the radially extending face surrounding the coolant passages of each adjacent member of the engine.", "Another prior design, U.S. Pat. No. 4,400,018 to Abbes, Rouaud, Forges, and de Villepoix (1983) discloses a seal assembly for joining two opposing pipe ends.", "The inside diameter of the seal assembly is as large or larger than the bore of the pipes that it connects.", "The two opposing flanges are flat except for a cradle for the extensible member to reside upon.", "The two opposing flanges must also be welded onto the end of each pipe.", "O-rings are used between the face of each flange and the extensible members.", "The assembly requires two separate extensible members with conical shaped faces.", "A two piece moveable member, with a double conical shape is wedged in between the extensible members and presses against the latter mentioned conical faces.", "The moveable member also bears against the rear faces of the radial flanges to prevent the pipes from moving apart.", "No part of this invention resides within the passages of the members or in this case pipes.", "Mounting relies on the front and back sides of external, flat, welded on flanges.", "All sealing is accomplished with two separate O-rings which each seal against three surfaces.", "The internal diameter of the tubular member is substantially the same diameter as the corresponding pipes.", "This seal assembly requires a multiple of flat radial surfaces for mounting means.", "The extensible members are of rigid material and do not serve to form the seal between the pipes.", "Sealing is accomplished by pressure exerted upon the.", "O-rings by the extensible member to form sealing contact between the flanges and the tubular member.", "It would be nearly impossible to utilize this seal assembly between rigidly mounted members of an engine which do not have several inches of space between them and which do not have a tubular projection with flanges incorporated upon them during their manufacture.", "Another prior art example is U.S. Pat. No. 4,417,735 to Heisler (1983) reveals a sealing device disposed between adjacent members of an engine.", "This design also has an inside diameter as large or larger than the bore of the passage in the members which it seals.", "A centering bead exists on one of the members to provide a means of locating the seal assembly.", "Clamping upon a trapezoidal shape is used to cause expansion outwardly against the members.", "This is, a rigid design with resilient material being used only in the form of gasketing applied to the outer surfaces.", "The sealing and mounting of this seal assembly is completely dependant on the protruding surfaces of the members being precisely machined to form a corresponding mechanical fit.", "This design allows a component such as a manifold to be removed without disturbing other members.", "However it does not allow for the seal itself to be installed or removed alone.", "The seal assembly must be placed upon one of the engine components while one of the component is being installed.", "Again, for reasons similar to those mentioned above, this seal assembly would be nearly impossible to use between rigidly mounted adjacent members of an engine.", "None of these prior art examples are capable of mounting within the bore of existing passages, or have any provisions for control of coolant flow.", "Further, none are capable of sealing where there are no special machined surfaces or other devices provided upon the face of each adjacent member.", "BRIEF SUMMARY OF THE INVENTION An object of this invention is to provide a more serviceable seal assembly of the above type, particularly adapted for applications in the cooling system of internal combustion engines.", "The seal assembly comprises an annular ferrule, an elastomeric seal circumferentially disposed thereabout and a pair of annular mounting rings.", "The annular mounting rings provide a radial surface to engage with the elastomeric seal and also extend into and seal within the coolant passage bore of each adjacent member.", "A clamping means circumferentially surrounds the seal and ferrule to apply a clamping force radially inwardly on the seal to expand the sidewalls thereof into sealing contact with the annular mounting rings.", "The annular mounting rings may also provide for control of coolant flow by selection of bore sizing.", "OBJECTS AND ADVANTAGES Accordingly, several objects and advantages of the present invention are;", "a) to provide a seal assembly which can easily be installed without removing any major engine members such as a cylinder head or front cover assembly;", "b) to provide a seal assembly which can easily be installed by hand without any additional machining, welding or fabrication;", "c) to provide a seal assembly which mounts and seals within opposing passages employed on members of an engine and which are separated from each other by a gap which is at least wide enough to install the various parts of the invention;", "d) to provide a seal assembly which utilizes existing bores within the members to provide all necessary mounting and alignment of the various parts of the seal assembly;", "e) to provide a seal assembly with a low overall profile which is tolerant of substantial contours, space limitations, or lack of a substantial radially flat area, which may be on or near the face of one or both adjacent members of the engine;", "f) to provide a seal assembly which can be more easily serviced when necessary to repair leaks or perform other maintenance;", "g) to provide a seal assembly which by it's construction is mostly reusable;", "h) to provide a seal assembly which by selective sizing of it's bore can be used to control the volume of coolant flow;", "i) to provide a seal assembly which no longer causes many other engine parts such as gaskets, seals, coolant, oil and filters, and other used but serviceable parts, which may not be at the end of their useful service life, to be replaced prematurely;", "j) to provide a seal assembly which is at least as reliable as prior art and has sufficient volume and shape of resilient material to withstand aging which is inherent with the frequent heating and cooling cycles common to internal combustion engines, thus not needing periodic adjusting of the clamping means or other undesirable maintenance.", "Further objects and advantages are to provide a seal assembly which can be utilized nearly anytime or anywhere an engine may be, including when a leak occurs on-the-job, avoiding the need for towing or more expensive damage and repairs due to loss of coolant.", "Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.", "BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a sectioned isometric view of a seal assembly embodying this invention, shown disposed between a pair of adjacent members to form a static seal within a common passageway formed therein;", "FIG. 2 is a view similar to FIG. 1, but illustrating the seal assembly in it's installed condition shown within and between sectioned members;", "FIG. 3 is a cross section exploded view of the parts of the seal, shown in the direction of arrows II—II in FIGS. 1 and 2, but not including the clamp which is of standard design;", "FIG. 4 is a cross section view illustrating the seal assembly, shown in the direction of arrows II—II in FIGS. 1 and 2 in it's installed condition between a pair of adjacent members to form a static seal within a common passageway formed therein;", "FIG. 5 is an expanded view showing the various parts of the seal assembly, but not showing the clamp and O-rings which are of standard design.", "REFERENCE NUMERALS 3 elastomeric seal 4 O-ring 5 annular mounting ring 6 clamp 7 ferrule 8 coolant passage 9 outwardly flange 10 flexible strap 11 member 12 seal bore 13 step 14 slots 15 step 16 inwardly flange 17 screw 18 O-ring groove 19 outwardly face 20 inwardly face 21 seal assembly DETAILED DESCRIPTION OF THE INVENTION FIG. 1 illustrates a seal assembly 21 disposed between a pair of adjacent members 11 , such as a cylinder head and front cover employed on an internal combustion engine.", "A common passageway 8 is formed in the members to communicate fluid therebetween, such as water or oil.", "As will be hereinafter fully described, the seal assembly comprises a pair of anmular mounting rings 5 installed and sealing within the members.", "An elastomeric seal 3 is placed ard expanded into sealing contact between the annular adapters to provide a static seal therein to prevent the egress of fluid thereby from passageway 8 .", "Referring to FIGS. 1 and 4, the seal assembly comprises an annular ferrule 7 having an elastomeric seal 3 circumferentially disposed thereabout, a pair of annular mounting rings 5 disposed generally within the stationary members 11 .", "As shown in FIG. 4, a static seal is formed within each member and the corresponding end of each annular mounting ring by an O-ring seal 4 circumferentially disposed thereabout within a corresponding circumferential groove 18 .", "However, it should be understood that the location of the O-ring and means other than an O-ring may be used to form a static seal between the annular mounting ring and the member, as is well known by those skilled in the arts relating hereto.", "As shown in FIG. 3, each annular mounting ring has on it's other end an integral radial flange 16 extending generally inwardly from the annulus.", "The outwardly face of said inwardly flange provides an area for the elastomeric seal to press and seal against.", "In applications where control of coolant flow is desired, the inwardly extending flange of each annular mounting ring has a bore 12 which can be selectively sized based on cooling system requirements.", "The overall length of each annular mounting ring must be less than the gap existing between the stationary members to facilitate installation without removal of either member.", "The inside diameter of the ferrule 7 is substantially the same as the bore 12 of the annular mounting rings.", "As shown in FIGS. 3 and 5, preformed into each sidewall of the elastomeric seal 3 and outwardly face of the inwardly flange of the annular mounting rings 5 is a contour in the form of a step 13 and 15 .", "The step can be defined generally by two different overall cross sectional widths of the elastomeric seal and the radial flange of the annular mounting rings.", "The step upon each face of the elastomeric seal corresponds with a like but directionally opposite step disposed upon the face of the radial flange of each annular mounting ring to provide a means for alignment.", "It is desirable for the height of each step disposed upon all described faces be equal to between 5% and 20% of the cross sectional thickness of the elastomeric seal with such height approximating 8%.", "The preferred diameter of the step 15 as viewed upon the face of the elastomeric seal and radial flange of the annular adapter rings is between 5% and 100% of overall face diameter with such diameter approximating 70%.", "However it should be understood that any combination of diameter or height of the step, or that nearly any corresponding surface variation may be used for alignment purposes as is well known by those skilled in the arts relating hereto.", "As shown in FIG. 3, the radial flange 16 of the annular mounting ring 5 viewed in cross section extends mostly radially inwardly from the annulus for the purpose described above.", "Each annular mounting ring also has a flange 9 extending radially outwardly a short distance.", "Flange 9 comprises an outwardly face 20 which provides additional area for the elastomeric seal.", "Said flange also comprises a inwardly face 19 which provides a means to limit the adapter's installed depth into the member.", "In so doing, outwardly flange serves to counteract the pressure exerted by the elastomeric seal.", "As shown in all figures, both inwardly and outwardly radially extending flanges upon each annular mounting ring share a generally common radial plane.", "However it should be understood that other means to limit the depth of insertion of the annular mounting ring into the member may cause the outwardly flange to be on a different plane than that mentioned above or not exist at all as is well known by those skilled in the arts relating hereto.", "As shown in FIGS. 1 and 4 a clamping means 6 circumferentially surrounds the elastomeric seal 3 for applying a clamping force radially inward on the outer surface of the seal to expand the sidewalls thereof into sealing contact with the annular mounting rings 5 .", "The clamping means may be of standard design as shown in FIG. 2 comprising a flexible strap 10 having a plurality of slots 14 formed therein to engage the spiraled threads (not shown) of a screw 17 .", "Thus, selective rotation of the screw in either direction will either contract or expand the strap 10 in a conventional manner.", "As further shown in FIGS. 1 and 4, installation of the elastomeric seal 3 and tightening of the clamping means 6 serves to hold the annular mounting rings tightly into the confines of the adjacent members and also serves to form a continuous conduit and static seal therewith.", "The elastomeric seal 3 is preferably composed of a resilient material such as suitably composed rubber based material which will exert the desired sealing forces between parts 5 .", "However it should be understood that other elastomeric materials may be used for the seal as is well known by those skilled in the arts relating hereto.", "Ferrule 7 and the annular mounting rings 5 may be composed of brass, composite, or like material which is non-corrosive when subjected to coolants such as water and strong enough to counteract the pressure from the elastomeric seal.", "The clamping means may be of standard composition which consists of stainless steel.", "DESCRIPTION OF THE PREFERRED EMBODIMENT Operation and use of the seal assembly is simple and straight forward.", "The old seal assembly, which the invention is intended to replace, resides in an exposed area between two major engine members.", "After a portion of the engine coolant has been drained the old seal assembly is removed by cutting it with a small hand or power activated saw to form shorter pieces which can be slid out from the bore of the coolant passage 8 .", "After removing the pieces, the bores which held the old seal are cleaned of rust and scale usually by sanding or scraping.", "An O-ring 4 is placed in a locating grove 18 on each annular mounting ring 5 .", "After applying a suitable lubricant, each annular mounting ring with the accompanying O-ring is slid into the bore of the coolant passage 8 of the adjacent engine members 11 .", "The support ferrule 7 is placed inside the elastomeric seal 3 and the clamp 6 is placed around the outside.", "This assembly is then inserted into a centered position between the annular mounting rings.", "The clamp is then tightened.", "This completes the installation of the invention.", "The job is complete when coolant is replaced back into the engine and a final check is made for any leaks.", "CONCLUSIONS, RAMIFICATIONS, AND SCOPE Accordingly, it can be seen that a seal assembly that can be installed without removal of any major engine members will save a great amount of mechanic's time, equipment down time, and money, when a leak in this area must be repaired.", "This is brought about by my invention which is at least as reliable as the original equipment seal, fits into existing bores within the coolant passages of two adjacent members, and into an area between the members which have no provisions manufactured onto their outer surface to accommodate other seal types.", "Because of the profile and nature of mounting, this new seal easily lends itself to applications where control of coolant flow is necessary.", "Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention.", "Various other embodiments and ramifications are possible within it's scope.", "For example, this invention would be well suited for sealing of opposing pipes, which are otherwise held in place, making a section or sections removable.", "Likewise, other uses could include a sealed passage between liquid or gas filled vessels or other compartments.", "This seal design is also capable of working with low to moderate pressures without the use of any circumferential clamping means by proper sizing of the elastomeric seal.", "Further uses, include a fixed outer ring in place of the clamping means and static sealing arranged by mechanical pressure exerted by the members upon the annular mounting rings to form sealing contact with the elastomeric seal.", "Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given." ]
PRIORITY CLAIM [0001] This application claims the benefit of priority from U.S. Provisional Patent application Ser. No. 61/884,112, entitled “Shared Tertiary Chain for Improved LTE Throughput” and filed Sep. 29, 2013, which is fully incorporated herein by reference for all purposes to the extent not inconsistent with this application. BACKGROUND [0002] This application is directed to wireless communications and, more particularly, to shared tertiary chain between GPS and 1× to improve LTE throughput on primary and secondary chains in wireless communications. [0003] Electronic devices such as portable computers and cellular telephones are often provided with wireless communication capabilities. For example, electronic devices may use long-range wireless communication circuitry such as cellular telephone circuitry and WiMAX (IEEE 802.16) circuitry. Electronic devices may also use short-range wireless communication circuitry such as WiFi® (IEEE 802.11) circuitry and Bluetooth® circuitry. [0004] In some devices, it may be desirable to support multiple radio access technologies. For example, it may be desirable to support newer radio-access technologies for handling data sessions and older radio-access technologies for supporting voice calls. Examples of different radio-access technologies that have been used in cellular telephones include Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Code Division Multiple Access (CDMA) (e.g., CDMA2000 including standards such as CDMA2000 1×RTT or 1×), and Long Term Evolution (LTE). [0005] In certain single radio LTE implementation, LTE and 1× operate in a hybrid mode of operation. This means that while LTE is operating using the single radio (i.e., in data traffic mode), the LTE operation can get interrupted periodically by 1× tune-aways. In this way, the single radio can periodically tune-away from an active LTE connection to check for paging messages, etc. on the 1× system, as well as, e.g., to measure the RF conditions. [0006] A tune-away, for example, can last approximately 100-200 msec, depending on network equipment design and 1× network performance, but mobile devices can stay on 1× for a much longer time. The following items describe example scenarios that may result in long tune-away times: 1) Voice calls—when the subscriber gets paged and picks up a voice call on the 1×interface, which might list a long time, 2) Idle handoffs—tune-away can last around a second, 3) Registrations—tune-away can last from a second or two to more than 10 seconds if the mobile device finds out that it has to register after tuning-away to 1×, 4) System lost—Tune-aways can last more than 5 seconds, up to tens of seconds. These system lost tune-away could be caused by common RF problems, like coverage holes, pilot pollution, or rapidly changing pilots. These 1×tune-away events can negatively impact LTE throughput. [0007] Therefore, it would be desirable to provide improved ways to support multiple radio access technologies in a single-radio electronic device without reducing LTE throughput. BRIEF DESCRIPTION OF THE DRAWINGS [0008] FIG. 1 illustrates an exemplary wireless multiple-access communication system according to certain embodiments; [0009] FIG. 2 illustrates a block diagram of an exemplary mobile device or user equipment (UE) according to certain embodiments; [0010] FIG. 3 illustrates a block diagram of an exemplary enhanced Node B (eNB) or similar mobile communication node (e.g., base station, access point, etc.) according to certain embodiments; [0011] FIG. 4 illustrates an exemplary multi-RAT wireless network according to certain embodiments; [0012] FIG. 5 illustrates an exemplary receive chain architecture according to certain embodiments; [0013] FIG. 6 illustrates an exemplary multi-receive chain architecture according to certain embodiments; and [0014] FIG. 7 illustrates an exemplary 1× tune-away flow diagram according to certain embodiments. DETAILED DESCRIPTION [0015] The following detailed description is directed to certain sample embodiments. However, the disclosure can be embodied in a multitude of different ways as defined and covered by the claims. In this description, reference is made to the drawings wherein like parts are designated with like reference numerals within this application. [0016] This disclosure makes reference to various wireless communication devices, such as access point, mobile device, handset, base station, user equipment, Node B, access terminal, eNB and the like. The use of these and other names that may be associated with specific technologies or standards is not intended to indicate or mandate one particular device, one particular standard or protocol, or one particular signaling direction and is expressly intended to not be limiting of the scope of this application in any way. The use of these and other names is strictly for convenience and such names may be interchanged within this application without any loss of coverage or rights. [0017] Various techniques described herein can be used for various wireless communication systems, technologies and/or networks, such as Code Division Multiple Access (“CDMA”) systems, Multiple-Carrier CDMA (“MCCDMA”), Wideband CDMA (“W-CDMA”), High-Speed Packet Access (“HSPA,” “HSPA+”) systems, Time Division Multiple Access (“TDMA”) systems, Frequency Division Multiple Access (“FDMA”) systems, Single-Carrier FDMA (“SC-FDMA”) systems, Orthogonal Frequency Division Multiple Access (“OFDMA”) systems, or other multiple access techniques. A wireless communication technique employing the teachings herein may be designed to implement one or more standards, such as IS-95, cdma2000, IS-856, W-CDMA, TDSCDMA, GSM, UMTS, LTE, WiFi, WiMAX and other standards. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (“UTRA)”, cdma2000, or some other technology. UTRA includes W-CDMA and Low Chip Rate (“LCR”). The cdma2000 technology covers IS-2000, IS-95 and IS-856 standards. A TDMA network may implement a radio technology such as Global System for Mobile Communications (“GSM”). An OFDMA network may implement a radio technology such as Evolved UTRA (“E-UTRA”), IEEE 802.11 (“WiFi”), IEEE 802.16 “(WiMAX”), IEEE 802.20 (“MBWA”), Flash-OFDM®, etc. UTRA, E-UTRA, and GSM are part of Universal Mobile Telecommunication System (“UMTS”). The teachings herein may be implemented in a 3GPP Long Term Evolution (“LTE”) system, an Ultra-Mobile Broadband (“UMB”) system, and other types of systems. LTE is a release of UMTS that uses E-UTRA. Although certain aspects of the disclosure may be described using 3GPP terminology, it is to be understood that the teachings herein may be applied to 3GPP (Re199, Re15, Re16, Re17, and so on) technology, as well as 3GPP2 (IxRTT, 1×EV-DO Re1O, RevA, RevB, and so on) technology and other technologies, such as WiFi, WiMAX, WMBA and the like. [0018] Referring to the drawings, FIG. 1 illustrates an exemplary wireless multiple-access communication system 100 according to certain embodiments. As shown in FIG. 1 , an enhanced Node B (eNB) base station 102 can include multiple antenna groups. One antenna group can include antennas 104 and 106 , another can include antennas 108 and 110 , and another can include antennas 112 and 114 . While only two antennas are shown in FIG. 1 for each antenna group, it should be appreciated that more or fewer antennas may be utilized for each antenna group. As shown, user equipment (UE) 116 can be in communication with antennas 112 and 114 , where antennas 112 and 114 transmit information to UE 116 over downlink (or forward link) 120 and receive information from UE 116 over uplink (or reverse link) 118 . Additionally and/or alternatively, UE 122 can be in communication with antennas 104 and 106 , where antennas 104 and 106 transmit information to UE 122 over downlink 126 and receive information from UE 122 over uplink 124 . In a frequency division duplex (FDD) system, communication links 118 , 120 , 124 and 126 can use different frequencies for communication. In time division duplex (TDD) systems, communication links 118 , 120 , 124 and 126 can use the same frequency or frequencies for communication, but can communicate at differing times. [0019] Each group of antennas and/or the area in which they are designed to communicate can be referred to as a sector of the eNB or base station. In accordance with one aspect, antenna groups can be designed to communicate to mobile devices in a sector of areas (not shown) covered by eNB 102 . In communication over downlinks 120 and 126 , the transmitting antennas of eNB 102 can utilize beamforming in order to improve the signal-to-noise ratio of downlinks for the different UEs 116 and 122 . Also, a base station using beamforming to transmit to UEs scattered randomly through its coverage area can cause less interference to mobile devices in neighboring cells or sectors than a base station transmitting through a single antenna to all of its UEs. In addition to beamforming, antenna groups of a base station, as well as mobile devices, can use other multi-antenna or antenna diversity techniques to send and/or receive information, such as spatial multiplexing, spatial diversity, pattern diversity, polarization diversity, transmit/receive diversity, adaptive arrays, and the like. [0020] FIG. 2 illustrates a block diagram 200 of an exemplary mobile device, handset (HS) or user equipment (UE) 210 according to certain embodiments. As shown in FIG. 2 , UE 210 may include a transceiver 220 , an antenna 230 , a processor 240 , and a memory 250 (which, in certain embodiments, may include memory in a Subscriber Identity Module (SIM) card). In certain embodiments, some or all of the functionalities described herein as being performed by a handset or mobile device may be provided by processor 240 executing instructions stored on a computer-readable medium, such as the memory 250 , as shown in FIG. 2 . Alternatively, processor 240 and/or memory 250 may be one or more separate processors and/or memories. Additionally, UE 210 may perform uplink and/or downlink communication functions, as further disclosed herein, via transceiver 220 and antenna 230 . While only one antenna and one transceiver are shown for UE 210 , certain embodiments are equally applicable to multi-antenna and/or multi-transceiver mobile devices. In certain embodiments, UE 210 may include additional components beyond those shown in FIG. 2 that may be responsible for enabling or performing the functions of UE 210 , such as communicating with a base station in a network and for processing information for transmitting or from reception, including any of the functionality described herein. Such additional components are not shown in FIG. 2 but are intended to be within the scope of coverage of this application. [0021] FIG. 3 illustrates a block diagram 300 of an exemplary enhanced Node B (eNB) 310 or similar mobile communication node (e.g., base station, access point, etc.) according to certain embodiments. As shown in FIG. 3 , eNB 310 may include a baseband processor 330 to provide radio communication with mobile handsets via a radio frequency (RF) transmitter 340 and RF receiver 350 units coupled to eNB antenna 320 . While only one antenna and one transceiver set are shown, certain embodiments are applicable to multi-antenna and/or multi-transceiver set configurations. RF transmitter 340 and RF receiver 350 may be combined into one, transceiver unit, and/or duplicated to facilitate multiple antenna communication. Baseband processor 330 may be configured (in hardware and/or software) to function according to a wireless communications standard, such as 3GPP LTE. Alternatively, multiple baseband processors may be included in eNB 310 . Baseband processor 330 may include a processing unit 332 in communication with a memory 334 to process and store relevant information for the eNB and a scheduler 336 , which may provide scheduling decisions for mobile devices serviced by eNB 310 . Scheduler 336 may have some or all of the same data structure as a typical scheduler for an eNB in an LTE system. Alternatively, processing unit 332 and/or memory 334 may be one or more separate processors and/or memories. In certain embodiments, some or all of the functionalities described herein as being performed by an enhanced Node B, access point or base station may be provided by processing unit 332 executing instructions stored on a computer-readable medium, such as memory 334 , as shown in FIG. 3 . [0022] Baseband processor 330 may also provide additional baseband signal processing (e.g., mobile device registration, channel signal information calculation and/or transmission, radio resource management, etc.) as required. Processing unit 332 may include, by way of example, one or more of the following: a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a microprocessor, a microprocessor in association with a DSP core, a controller, a microcontroller, an Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, and any other type of integrated circuit (IC) and/or state machine. Some or all of the functionalities described herein as being provided by a mobile base station, a base station controller, a node B, an enhanced node B, an access point, a home base station, a femtocell base station, and/or any other type of mobile communications node may be provided by processing unit 332 executing instructions stored on a computer-readable data storage medium, such as the memory 334 shown in FIG. 3 . [0023] In certain embodiments, eNB 310 may further include a timing and control unit 360 and a core network interface unit 370 , such as are shown in FIG. 3 , each in communication with the other and with baseband processor 330 . Timing and control unit 360 may monitor operations of baseband processor 330 and network interface unit 370 , and may provide appropriate timing and control signals to these units. Network interface unit 370 may provide a bi-directional interface for eNB 310 to communicate with a core or back-end network (not shown) to facilitate administrative, data-management and/or call-management functions for mobile subscribers operating in the network through eNB 310 . [0024] In certain embodiments, base station 310 may include additional components responsible for providing additional functionality, including any of the functionality identified herein and/or any functionality necessary to support the techniques described herein. Although features and elements are described in particular combinations, each feature or element can be used alone without the other features and elements or in various combinations with or without one or more features and elements. Techniques provided herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable storage medium (e.g., memory 334 in FIG. 3 ) for execution by a general purpose computer or a processor (e.g., processing unit 332 in FIG. 3 ). Examples of computer-readable storage media include read only memory (ROM), random access memory (RAM), digital registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks, magnetic tapes and removable disks, magneto-optical media, and optical media such as CDROM disks, digital versatile disks (DVDs), and so on. Such computer-readable storage media may be separate units, may be incorporated as part of one or more other units (e.g., processing unit 332 in FIG. 3 ), or may be a combination of separate and incorporated units. [0025] FIG. 4 illustrates an exemplary multi-RAT (radio access technology) wireless network 400 according to certain embodiments. As shown in FIG. 4 , a mobile device (handset, UE, etc.) 430 is within the coverage area of multi-RAT wireless network 400 . Multi-RAT wireless network 400 can include multiple-technology network coverage pieces. For example, one technology coverage area can be a cell 410 A, such as in an LTE coverage area. Within (or partially within) cell 410 A coverage area, there can concurrently exist one or more other technology coverage areas, for example cells 410 B and 410 C, each of which may be a GSM, UMTS, WiMAX, CDMA or even WiFi coverage area. As shown, cells 410 B, 410 C are within cell 410 A and at least partially overlap each other, although this configuration is for illustrative purposes only. Each cell 410 can also include some sort of network access device 420 A, 420 B and 420 C, such as a base station, eNodeB or access point. Each network access device 420 can communicate with one or more mobile devices 430 , as well as with a core network 440 (and even, perhaps, with each other). Not shown are possible intermediate network components or system elements that may be between each network access device 420 and core network 440 . In certain embodiments, mobile device 430 can be moving within cell 410 A and moving out of cell 410 B and into cell 410 C. In this way, mobile device 430 could possibly communicate with one or more of cells 410 A, 410 B and 410 C. [0026] FIG. 5 illustrates an exemplary receive chain architecture 500 according to certain embodiments. As shown in FIG. 5 , an antenna 510 can receive the radio frequency (RF) signals, which are then filtered by one or more RF filters 520 . The RF filtered signal next passes through one or more low noise amplifiers (LNAs) 530 . Next the signal leaves the LNA and enters a mixer 540 , which also has as an input a phase-locked loop (PLL)/voltage controlled oscillator (VCO) 550 output. After mixing, the signal passes through one or more intermediate frequency (IF) filters 560 and into an automatic gain control (AGC) 570 module. Finally, the signal may be filtered by one or more filters ( 580 ) and then converted from analog to digital form by analog-to-digital converter (ADC) 590 . As used in this application, certain embodiments of receive chain architecture 500 can be used with and/or within UE 200 , eNB 300 and/or any devices associated with FIGS. 1-4 . [0027] FIG. 6 illustrates an exemplary multi-receive chain architecture 600 according to certain embodiments. As shown in FIG. 6 , multiple receive chains 610 a - x can include multiple PLLs 620 a - y . Not shown are the one or more antennas that may be connected to multiple receive chains 610 . Note that it is not necessary that there be a one-to-one correlation between the number of PLLs to receive chains. As used in this application, certain embodiments of multi-receive chain architecture 600 can be used with and/or within UE 200 , eNB 300 and/or any devices associated with FIGS. 1-4 , in which any one or more of multiple receive chains 610 a - x can include some or all of the elements of receive chain architecture 500 . [0028] In certain embodiments, a multi-RAT, single-radio handset or user equipment (UE) may include three receive chains with two PLLs. For example, this UE may be able to operate using 4G (e.g., LTE) for data services, but fall back to 2G/3G (e.g., CDMA2000 1×RTT, or just “1×”) for voice services, which means that LTE and 1× will operate in a hybrid mode, with LTE traffic being interrupted periodically by a 1× “tune-away.” As used herein, a 1× tune-away may be, for example, ceasing reception/processing of LTE incoming data, receiving/listening for/demodulating paging messages that might indicate an incoming call (or no incoming call, as the case may be), and then retuning for continued reception of LTE data. Each 1× tune-away can negatively impact the LTE throughput. The negative impact can be larger when the UE is in a marginal coverage area because the UE may need to wake-up in IS 2000 or paging channel timeline for 1×. [0029] In certain embodiments, the single radio, three receive chains, two PLLs UE may be configured as follows. The primary and secondary receive chains can be used for 1×, EV/DO and/or LTE operation, while the tertiary receive chain can be dedicated for GPS operations. One or both of the two PLLs can be used for one technology with diversity, which means that one PLL can be used to receive LTE data traffic on both the primary and secondary receive chains. This leaves the second PLL to be used for GPS operation on the tertiary receive chain or used for a 1× tune-away one of the primary or secondary receive chains. The potential issue with this configuration is that when a 1× tune-away must happen during a time with LTE data reception is happening, the LTE data reception must be stopped for the 1× tune-away to occur. Also, if GPS is using the second PLL, then the first PLL must also be taken from the LTE reception set-up and used for the 1× tune-away. [0030] FIG. 7 illustrates an exemplary 1× tune-away flow diagram 700 according to certain embodiments. In certain embodiments, a 1× tune-away can be permitted to use the second PLL and the tertiary receive chain if GPS is not using them, or if certain conditions are met, even if GPS is using them. As shown in FIG. 7 , at 710 , a UE with a single radio and three receive chains is in LTE active mode, i.e., it is actively receiving LTE data. At 720 , the UE decides whether it is time for a 1× tune-away. If it is not time for a 1× tune-away, then the UE can continue in active LTE mode at 710 . If at 720 it is time for a 1× tune-away, then at 730 , the UE can determine whether the LTE active mode is using both the primary and secondary receive chains. If not (and assuming that the LTE active mode is using the primary receive chain, which need not be the case), then the 1× tune-away can use the secondary receive chain (or more generally, the receive chain that is not being used by the LTE active mode). [0031] If the check at 730 indicates that LTE mode is using both the primary and secondary receive chains, then at 740 the UE can determine whether GPS is active, which indicates whether the tertiary receive chain is in use. If at 740 GPS is not active, then at 745 the 1× tune-away can use the tertiary receive chain. If at 740 GPS is active, then at 750 , the UE can determine whether it is in a marginal 1× coverage area. If the UE is not in a marginal 1× coverage area, then at 755 the 1× tune-away can use the tertiary receive chain, which means that GPS will temporarily loose use of the tertiary receive chain. After the 1× tune-away is complete from 755 , then at 770 the UE can return to GPS active mode. [0032] If the check at 750 indicates that the UE is in a marginal 1× coverage area, then at 760 the UE can determine whether precise GPS is needed for the application or applications that are running and in need of GPS data. If precise GPS data are not needed, then at 765 the 1× tune-away can use the tertiary receive chain, which means that GPS will temporarily loose use of the tertiary receive chain. After the 1× tune-away is complete from 765 , then at 770 the UE can return to GPS active mode. If at 760 precise GPS data are needed by the running application(s), then at 780 the 1× tune-away can use the primary and/or the secondary receive chain(s), which means that LTE will temporarily loose use of the one or both of the primary and secondary receive chains. After the 1× tune-away is complete from 780 , then at 710 the UE can return to LTE active mode. [0033] In certain embodiments, as discussed herein with reference to FIG. 7 , if LTE is using both primary and secondary receive chains ( 730 ) and GPS is active ( 740 ) and UE is in a marginal coverage area ( 750 ) and precise GPS data are needed ( 760 ) will the 1× tune-away ( 720 ) interrupt the active LTE mode ( 710 ) by using one or both of the primary and secondary receive chains ( 780 ). In this way, LTE can remain active in most situations. [0034] Certain embodiments may deviate from the certain embodiments described so far. For example, while FIG. 7 is discussed with reference to a UE having three receive chains, techniques of this application can be applicable to fewer or more receive chains. In the case of fewer, (e.g., two) receive chains, then the LTE active mode could be assigned only the primary receive chain (i.e., eliminating the need for the 730 check and 735 no result from that check). [0035] Those of ordinary skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof [0036] Those of ordinary skill would further appreciate that the various illustrative logical blocks, modules, and algorithm steps described in connection with the examples disclosed herein may be implemented as electronic hardware, firmware, computer software, middleware, microcode, or combinations thereof. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints or preferences imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosed methods. [0037] The various illustrative logical blocks, components, modules, and circuits described in connection with the examples disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. [0038] The steps of a method or algorithm described in connection with the examples disclosed herein may be embodied directly in hardware, in one or more software modules executed by one or more processing elements, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form or combination of storage medium known in the art. An example storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an Application Specific Integrated Circuit (ASIC). The ASIC may reside in a wireless modem. In the alternative, the processor and the storage medium may reside as discrete components in the wireless modem. [0039] The previous description of the disclosed examples is provided to enable any person of ordinary skill in the art to make or use the disclosed methods and apparatus. Various modifications to these examples will be readily apparent to those skilled in the art, and the principles defined herein may be applied to other examples and additional elements may be added.
In a wireless communication device that has LTE and 1 ×capabilities and multiple receive chains, this application provides for sharing non-LTE receive chain(s) and/or unused LTE receive chain(s) for 1× tune-away events to improve LTE throughput by not interrupting LTE data transmission on the LTE active receive chain(s).
Briefly describe the main invention outlined in the provided context.
[ "PRIORITY CLAIM [0001] This application claims the benefit of priority from U.S. Provisional Patent application Ser.", "No. 61/884,112, entitled “Shared Tertiary Chain for Improved LTE Throughput”", "and filed Sep. 29, 2013, which is fully incorporated herein by reference for all purposes to the extent not inconsistent with this application.", "BACKGROUND [0002] This application is directed to wireless communications and, more particularly, to shared tertiary chain between GPS and 1× to improve LTE throughput on primary and secondary chains in wireless communications.", "[0003] Electronic devices such as portable computers and cellular telephones are often provided with wireless communication capabilities.", "For example, electronic devices may use long-range wireless communication circuitry such as cellular telephone circuitry and WiMAX (IEEE 802.16) circuitry.", "Electronic devices may also use short-range wireless communication circuitry such as WiFi® (IEEE 802.11) circuitry and Bluetooth® circuitry.", "[0004] In some devices, it may be desirable to support multiple radio access technologies.", "For example, it may be desirable to support newer radio-access technologies for handling data sessions and older radio-access technologies for supporting voice calls.", "Examples of different radio-access technologies that have been used in cellular telephones include Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Code Division Multiple Access (CDMA) (e.g., CDMA2000 including standards such as CDMA2000 1×RTT or 1×), and Long Term Evolution (LTE).", "[0005] In certain single radio LTE implementation, LTE and 1× operate in a hybrid mode of operation.", "This means that while LTE is operating using the single radio (i.e., in data traffic mode), the LTE operation can get interrupted periodically by 1× tune-aways.", "In this way, the single radio can periodically tune-away from an active LTE connection to check for paging messages, etc.", "on the 1× system, as well as, e.g., to measure the RF conditions.", "[0006] A tune-away, for example, can last approximately 100-200 msec, depending on network equipment design and 1× network performance, but mobile devices can stay on 1× for a much longer time.", "The following items describe example scenarios that may result in long tune-away times: 1) Voice calls—when the subscriber gets paged and picks up a voice call on the 1×interface, which might list a long time, 2) Idle handoffs—tune-away can last around a second, 3) Registrations—tune-away can last from a second or two to more than 10 seconds if the mobile device finds out that it has to register after tuning-away to 1×, 4) System lost—Tune-aways can last more than 5 seconds, up to tens of seconds.", "These system lost tune-away could be caused by common RF problems, like coverage holes, pilot pollution, or rapidly changing pilots.", "These 1×tune-away events can negatively impact LTE throughput.", "[0007] Therefore, it would be desirable to provide improved ways to support multiple radio access technologies in a single-radio electronic device without reducing LTE throughput.", "BRIEF DESCRIPTION OF THE DRAWINGS [0008] FIG. 1 illustrates an exemplary wireless multiple-access communication system according to certain embodiments;", "[0009] FIG. 2 illustrates a block diagram of an exemplary mobile device or user equipment (UE) according to certain embodiments;", "[0010] FIG. 3 illustrates a block diagram of an exemplary enhanced Node B (eNB) or similar mobile communication node (e.g., base station, access point, etc.) according to certain embodiments;", "[0011] FIG. 4 illustrates an exemplary multi-RAT wireless network according to certain embodiments;", "[0012] FIG. 5 illustrates an exemplary receive chain architecture according to certain embodiments;", "[0013] FIG. 6 illustrates an exemplary multi-receive chain architecture according to certain embodiments;", "and [0014] FIG. 7 illustrates an exemplary 1× tune-away flow diagram according to certain embodiments.", "DETAILED DESCRIPTION [0015] The following detailed description is directed to certain sample embodiments.", "However, the disclosure can be embodied in a multitude of different ways as defined and covered by the claims.", "In this description, reference is made to the drawings wherein like parts are designated with like reference numerals within this application.", "[0016] This disclosure makes reference to various wireless communication devices, such as access point, mobile device, handset, base station, user equipment, Node B, access terminal, eNB and the like.", "The use of these and other names that may be associated with specific technologies or standards is not intended to indicate or mandate one particular device, one particular standard or protocol, or one particular signaling direction and is expressly intended to not be limiting of the scope of this application in any way.", "The use of these and other names is strictly for convenience and such names may be interchanged within this application without any loss of coverage or rights.", "[0017] Various techniques described herein can be used for various wireless communication systems, technologies and/or networks, such as Code Division Multiple Access (“CDMA”) systems, Multiple-Carrier CDMA (“MCCDMA”), Wideband CDMA (“W-CDMA”), High-Speed Packet Access (“HSPA,” “HSPA+”) systems, Time Division Multiple Access (“TDMA”) systems, Frequency Division Multiple Access (“FDMA”) systems, Single-Carrier FDMA (“SC-FDMA”) systems, Orthogonal Frequency Division Multiple Access (“OFDMA”) systems, or other multiple access techniques.", "A wireless communication technique employing the teachings herein may be designed to implement one or more standards, such as IS-95, cdma2000, IS-856, W-CDMA, TDSCDMA, GSM, UMTS, LTE, WiFi, WiMAX and other standards.", "A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (“UTRA)”, cdma2000, or some other technology.", "UTRA includes W-CDMA and Low Chip Rate (“LCR”).", "The cdma2000 technology covers IS-2000, IS-95 and IS-856 standards.", "A TDMA network may implement a radio technology such as Global System for Mobile Communications (“GSM”).", "An OFDMA network may implement a radio technology such as Evolved UTRA (“E-UTRA”), IEEE 802.11 (“WiFi”), IEEE 802.16 “(WiMAX”), IEEE 802.20 (“MBWA”), Flash-OFDM®, etc.", "UTRA, E-UTRA, and GSM are part of Universal Mobile Telecommunication System (“UMTS”).", "The teachings herein may be implemented in a 3GPP Long Term Evolution (“LTE”) system, an Ultra-Mobile Broadband (“UMB”) system, and other types of systems.", "LTE is a release of UMTS that uses E-UTRA.", "Although certain aspects of the disclosure may be described using 3GPP terminology, it is to be understood that the teachings herein may be applied to 3GPP (Re199, Re15, Re16, Re17, and so on) technology, as well as 3GPP2 (IxRTT, 1×EV-DO Re1O, RevA, RevB, and so on) technology and other technologies, such as WiFi, WiMAX, WMBA and the like.", "[0018] Referring to the drawings, FIG. 1 illustrates an exemplary wireless multiple-access communication system 100 according to certain embodiments.", "As shown in FIG. 1 , an enhanced Node B (eNB) base station 102 can include multiple antenna groups.", "One antenna group can include antennas 104 and 106 , another can include antennas 108 and 110 , and another can include antennas 112 and 114 .", "While only two antennas are shown in FIG. 1 for each antenna group, it should be appreciated that more or fewer antennas may be utilized for each antenna group.", "As shown, user equipment (UE) 116 can be in communication with antennas 112 and 114 , where antennas 112 and 114 transmit information to UE 116 over downlink (or forward link) 120 and receive information from UE 116 over uplink (or reverse link) 118 .", "Additionally and/or alternatively, UE 122 can be in communication with antennas 104 and 106 , where antennas 104 and 106 transmit information to UE 122 over downlink 126 and receive information from UE 122 over uplink 124 .", "In a frequency division duplex (FDD) system, communication links 118 , 120 , 124 and 126 can use different frequencies for communication.", "In time division duplex (TDD) systems, communication links 118 , 120 , 124 and 126 can use the same frequency or frequencies for communication, but can communicate at differing times.", "[0019] Each group of antennas and/or the area in which they are designed to communicate can be referred to as a sector of the eNB or base station.", "In accordance with one aspect, antenna groups can be designed to communicate to mobile devices in a sector of areas (not shown) covered by eNB 102 .", "In communication over downlinks 120 and 126 , the transmitting antennas of eNB 102 can utilize beamforming in order to improve the signal-to-noise ratio of downlinks for the different UEs 116 and 122 .", "Also, a base station using beamforming to transmit to UEs scattered randomly through its coverage area can cause less interference to mobile devices in neighboring cells or sectors than a base station transmitting through a single antenna to all of its UEs.", "In addition to beamforming, antenna groups of a base station, as well as mobile devices, can use other multi-antenna or antenna diversity techniques to send and/or receive information, such as spatial multiplexing, spatial diversity, pattern diversity, polarization diversity, transmit/receive diversity, adaptive arrays, and the like.", "[0020] FIG. 2 illustrates a block diagram 200 of an exemplary mobile device, handset (HS) or user equipment (UE) 210 according to certain embodiments.", "As shown in FIG. 2 , UE 210 may include a transceiver 220 , an antenna 230 , a processor 240 , and a memory 250 (which, in certain embodiments, may include memory in a Subscriber Identity Module (SIM) card).", "In certain embodiments, some or all of the functionalities described herein as being performed by a handset or mobile device may be provided by processor 240 executing instructions stored on a computer-readable medium, such as the memory 250 , as shown in FIG. 2 .", "Alternatively, processor 240 and/or memory 250 may be one or more separate processors and/or memories.", "Additionally, UE 210 may perform uplink and/or downlink communication functions, as further disclosed herein, via transceiver 220 and antenna 230 .", "While only one antenna and one transceiver are shown for UE 210 , certain embodiments are equally applicable to multi-antenna and/or multi-transceiver mobile devices.", "In certain embodiments, UE 210 may include additional components beyond those shown in FIG. 2 that may be responsible for enabling or performing the functions of UE 210 , such as communicating with a base station in a network and for processing information for transmitting or from reception, including any of the functionality described herein.", "Such additional components are not shown in FIG. 2 but are intended to be within the scope of coverage of this application.", "[0021] FIG. 3 illustrates a block diagram 300 of an exemplary enhanced Node B (eNB) 310 or similar mobile communication node (e.g., base station, access point, etc.) according to certain embodiments.", "As shown in FIG. 3 , eNB 310 may include a baseband processor 330 to provide radio communication with mobile handsets via a radio frequency (RF) transmitter 340 and RF receiver 350 units coupled to eNB antenna 320 .", "While only one antenna and one transceiver set are shown, certain embodiments are applicable to multi-antenna and/or multi-transceiver set configurations.", "RF transmitter 340 and RF receiver 350 may be combined into one, transceiver unit, and/or duplicated to facilitate multiple antenna communication.", "Baseband processor 330 may be configured (in hardware and/or software) to function according to a wireless communications standard, such as 3GPP LTE.", "Alternatively, multiple baseband processors may be included in eNB 310 .", "Baseband processor 330 may include a processing unit 332 in communication with a memory 334 to process and store relevant information for the eNB and a scheduler 336 , which may provide scheduling decisions for mobile devices serviced by eNB 310 .", "Scheduler 336 may have some or all of the same data structure as a typical scheduler for an eNB in an LTE system.", "Alternatively, processing unit 332 and/or memory 334 may be one or more separate processors and/or memories.", "In certain embodiments, some or all of the functionalities described herein as being performed by an enhanced Node B, access point or base station may be provided by processing unit 332 executing instructions stored on a computer-readable medium, such as memory 334 , as shown in FIG. 3 .", "[0022] Baseband processor 330 may also provide additional baseband signal processing (e.g., mobile device registration, channel signal information calculation and/or transmission, radio resource management, etc.) as required.", "Processing unit 332 may include, by way of example, one or more of the following: a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a microprocessor, a microprocessor in association with a DSP core, a controller, a microcontroller, an Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, and any other type of integrated circuit (IC) and/or state machine.", "Some or all of the functionalities described herein as being provided by a mobile base station, a base station controller, a node B, an enhanced node B, an access point, a home base station, a femtocell base station, and/or any other type of mobile communications node may be provided by processing unit 332 executing instructions stored on a computer-readable data storage medium, such as the memory 334 shown in FIG. 3 .", "[0023] In certain embodiments, eNB 310 may further include a timing and control unit 360 and a core network interface unit 370 , such as are shown in FIG. 3 , each in communication with the other and with baseband processor 330 .", "Timing and control unit 360 may monitor operations of baseband processor 330 and network interface unit 370 , and may provide appropriate timing and control signals to these units.", "Network interface unit 370 may provide a bi-directional interface for eNB 310 to communicate with a core or back-end network (not shown) to facilitate administrative, data-management and/or call-management functions for mobile subscribers operating in the network through eNB 310 .", "[0024] In certain embodiments, base station 310 may include additional components responsible for providing additional functionality, including any of the functionality identified herein and/or any functionality necessary to support the techniques described herein.", "Although features and elements are described in particular combinations, each feature or element can be used alone without the other features and elements or in various combinations with or without one or more features and elements.", "Techniques provided herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable storage medium (e.g., memory 334 in FIG. 3 ) for execution by a general purpose computer or a processor (e.g., processing unit 332 in FIG. 3 ).", "Examples of computer-readable storage media include read only memory (ROM), random access memory (RAM), digital registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks, magnetic tapes and removable disks, magneto-optical media, and optical media such as CDROM disks, digital versatile disks (DVDs), and so on.", "Such computer-readable storage media may be separate units, may be incorporated as part of one or more other units (e.g., processing unit 332 in FIG. 3 ), or may be a combination of separate and incorporated units.", "[0025] FIG. 4 illustrates an exemplary multi-RAT (radio access technology) wireless network 400 according to certain embodiments.", "As shown in FIG. 4 , a mobile device (handset, UE, etc.) 430 is within the coverage area of multi-RAT wireless network 400 .", "Multi-RAT wireless network 400 can include multiple-technology network coverage pieces.", "For example, one technology coverage area can be a cell 410 A, such as in an LTE coverage area.", "Within (or partially within) cell 410 A coverage area, there can concurrently exist one or more other technology coverage areas, for example cells 410 B and 410 C, each of which may be a GSM, UMTS, WiMAX, CDMA or even WiFi coverage area.", "As shown, cells 410 B, 410 C are within cell 410 A and at least partially overlap each other, although this configuration is for illustrative purposes only.", "Each cell 410 can also include some sort of network access device 420 A, 420 B and 420 C, such as a base station, eNodeB or access point.", "Each network access device 420 can communicate with one or more mobile devices 430 , as well as with a core network 440 (and even, perhaps, with each other).", "Not shown are possible intermediate network components or system elements that may be between each network access device 420 and core network 440 .", "In certain embodiments, mobile device 430 can be moving within cell 410 A and moving out of cell 410 B and into cell 410 C. In this way, mobile device 430 could possibly communicate with one or more of cells 410 A, 410 B and 410 C. [0026] FIG. 5 illustrates an exemplary receive chain architecture 500 according to certain embodiments.", "As shown in FIG. 5 , an antenna 510 can receive the radio frequency (RF) signals, which are then filtered by one or more RF filters 520 .", "The RF filtered signal next passes through one or more low noise amplifiers (LNAs) 530 .", "Next the signal leaves the LNA and enters a mixer 540 , which also has as an input a phase-locked loop (PLL)/voltage controlled oscillator (VCO) 550 output.", "After mixing, the signal passes through one or more intermediate frequency (IF) filters 560 and into an automatic gain control (AGC) 570 module.", "Finally, the signal may be filtered by one or more filters ( 580 ) and then converted from analog to digital form by analog-to-digital converter (ADC) 590 .", "As used in this application, certain embodiments of receive chain architecture 500 can be used with and/or within UE 200 , eNB 300 and/or any devices associated with FIGS. 1-4 .", "[0027] FIG. 6 illustrates an exemplary multi-receive chain architecture 600 according to certain embodiments.", "As shown in FIG. 6 , multiple receive chains 610 a - x can include multiple PLLs 620 a - y .", "Not shown are the one or more antennas that may be connected to multiple receive chains 610 .", "Note that it is not necessary that there be a one-to-one correlation between the number of PLLs to receive chains.", "As used in this application, certain embodiments of multi-receive chain architecture 600 can be used with and/or within UE 200 , eNB 300 and/or any devices associated with FIGS. 1-4 , in which any one or more of multiple receive chains 610 a - x can include some or all of the elements of receive chain architecture 500 .", "[0028] In certain embodiments, a multi-RAT, single-radio handset or user equipment (UE) may include three receive chains with two PLLs.", "For example, this UE may be able to operate using 4G (e.g., LTE) for data services, but fall back to 2G/3G (e.g., CDMA2000 1×RTT, or just “1×”) for voice services, which means that LTE and 1× will operate in a hybrid mode, with LTE traffic being interrupted periodically by a 1× “tune-away.”", "As used herein, a 1× tune-away may be, for example, ceasing reception/processing of LTE incoming data, receiving/listening for/demodulating paging messages that might indicate an incoming call (or no incoming call, as the case may be), and then retuning for continued reception of LTE data.", "Each 1× tune-away can negatively impact the LTE throughput.", "The negative impact can be larger when the UE is in a marginal coverage area because the UE may need to wake-up in IS 2000 or paging channel timeline for 1×.", "[0029] In certain embodiments, the single radio, three receive chains, two PLLs UE may be configured as follows.", "The primary and secondary receive chains can be used for 1×, EV/DO and/or LTE operation, while the tertiary receive chain can be dedicated for GPS operations.", "One or both of the two PLLs can be used for one technology with diversity, which means that one PLL can be used to receive LTE data traffic on both the primary and secondary receive chains.", "This leaves the second PLL to be used for GPS operation on the tertiary receive chain or used for a 1× tune-away one of the primary or secondary receive chains.", "The potential issue with this configuration is that when a 1× tune-away must happen during a time with LTE data reception is happening, the LTE data reception must be stopped for the 1× tune-away to occur.", "Also, if GPS is using the second PLL, then the first PLL must also be taken from the LTE reception set-up and used for the 1× tune-away.", "[0030] FIG. 7 illustrates an exemplary 1× tune-away flow diagram 700 according to certain embodiments.", "In certain embodiments, a 1× tune-away can be permitted to use the second PLL and the tertiary receive chain if GPS is not using them, or if certain conditions are met, even if GPS is using them.", "As shown in FIG. 7 , at 710 , a UE with a single radio and three receive chains is in LTE active mode, i.e., it is actively receiving LTE data.", "At 720 , the UE decides whether it is time for a 1× tune-away.", "If it is not time for a 1× tune-away, then the UE can continue in active LTE mode at 710 .", "If at 720 it is time for a 1× tune-away, then at 730 , the UE can determine whether the LTE active mode is using both the primary and secondary receive chains.", "If not (and assuming that the LTE active mode is using the primary receive chain, which need not be the case), then the 1× tune-away can use the secondary receive chain (or more generally, the receive chain that is not being used by the LTE active mode).", "[0031] If the check at 730 indicates that LTE mode is using both the primary and secondary receive chains, then at 740 the UE can determine whether GPS is active, which indicates whether the tertiary receive chain is in use.", "If at 740 GPS is not active, then at 745 the 1× tune-away can use the tertiary receive chain.", "If at 740 GPS is active, then at 750 , the UE can determine whether it is in a marginal 1× coverage area.", "If the UE is not in a marginal 1× coverage area, then at 755 the 1× tune-away can use the tertiary receive chain, which means that GPS will temporarily loose use of the tertiary receive chain.", "After the 1× tune-away is complete from 755 , then at 770 the UE can return to GPS active mode.", "[0032] If the check at 750 indicates that the UE is in a marginal 1× coverage area, then at 760 the UE can determine whether precise GPS is needed for the application or applications that are running and in need of GPS data.", "If precise GPS data are not needed, then at 765 the 1× tune-away can use the tertiary receive chain, which means that GPS will temporarily loose use of the tertiary receive chain.", "After the 1× tune-away is complete from 765 , then at 770 the UE can return to GPS active mode.", "If at 760 precise GPS data are needed by the running application(s), then at 780 the 1× tune-away can use the primary and/or the secondary receive chain(s), which means that LTE will temporarily loose use of the one or both of the primary and secondary receive chains.", "After the 1× tune-away is complete from 780 , then at 710 the UE can return to LTE active mode.", "[0033] In certain embodiments, as discussed herein with reference to FIG. 7 , if LTE is using both primary and secondary receive chains ( 730 ) and GPS is active ( 740 ) and UE is in a marginal coverage area ( 750 ) and precise GPS data are needed ( 760 ) will the 1× tune-away ( 720 ) interrupt the active LTE mode ( 710 ) by using one or both of the primary and secondary receive chains ( 780 ).", "In this way, LTE can remain active in most situations.", "[0034] Certain embodiments may deviate from the certain embodiments described so far.", "For example, while FIG. 7 is discussed with reference to a UE having three receive chains, techniques of this application can be applicable to fewer or more receive chains.", "In the case of fewer, (e.g., two) receive chains, then the LTE active mode could be assigned only the primary receive chain (i.e., eliminating the need for the 730 check and 735 no result from that check).", "[0035] Those of ordinary skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques.", "For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof [0036] Those of ordinary skill would further appreciate that the various illustrative logical blocks, modules, and algorithm steps described in connection with the examples disclosed herein may be implemented as electronic hardware, firmware, computer software, middleware, microcode, or combinations thereof.", "To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality.", "Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints or preferences imposed on the overall system.", "Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosed methods.", "[0037] The various illustrative logical blocks, components, modules, and circuits described in connection with the examples disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein.", "A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine.", "A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.", "[0038] The steps of a method or algorithm described in connection with the examples disclosed herein may be embodied directly in hardware, in one or more software modules executed by one or more processing elements, or in a combination of the two.", "A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form or combination of storage medium known in the art.", "An example storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium.", "In the alternative, the storage medium may be integral to the processor.", "The processor and the storage medium may reside in an Application Specific Integrated Circuit (ASIC).", "The ASIC may reside in a wireless modem.", "In the alternative, the processor and the storage medium may reside as discrete components in the wireless modem.", "[0039] The previous description of the disclosed examples is provided to enable any person of ordinary skill in the art to make or use the disclosed methods and apparatus.", "Various modifications to these examples will be readily apparent to those skilled in the art, and the principles defined herein may be applied to other examples and additional elements may be added." ]
This is a division of application Ser. No. 765,476 filed Aug. 14, 1985 now U.S. Pat. No. 4,661,301 issued Apr. 28, 1987. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention conerns a laminate board which is applicable to the manufacture of a printed circuit board and a process for continuous molding of a plate for use in producing the laminate board. 2. Description of the Prior Art It is well-known that a material having a low dielectric constant (Er) and dissipation factor (tan δ) is advantageous for use in printed circuit boards. As the dielectric constant goes down, the electric performance, as measured by time delay, capacitance, and other factors, is improved. Many materials having a low dielectric constant, such as polyethylene, poly 4-methyl pentene-1, polystyrene, polytetrafluoroethylene are not necessarily suitable for use in printed circuit boards from the viewpoints of heat resistance, cost or processability. Incorporation of a filler into a resin is a well-known technique for improving properties of the resin such as electric, optical, mechanical, electromagnetic, frictional, chemical and other properties. One method for lowering the dielectric constant of a material is to incorporate a filler such as one consisting of hollow microspheres, as disclosed in Japanese Patent Publication No. 18353/82 (Tokko-sho 57-18353); and F. W. Haining & D. G. Herbaugh, IBM TECH. DISCLOSURE BULL (USA) Vol. 22. No. 5, 1799, October 1979. The glass epoxy laminates prepared by conventional processes according to the above method using epoxy/microsphere prepregs, however, do not necessarily perform well in a printed circuit board. For example, the board's deviation from flatness, such as bending and twisting causes problems in subsequent treatments such as soldering, etching, drilling, laminating of resist, and plating. These defects may be due to uneven distribution of the filler in the prepregs. Furthermore, the electrical insulation of the board is not as large as is required when the board is immersed in boiling water. Voids formed between the filler and the reinforcing fabric are considered responsible for these disadvantages. SUMMARY OF THE INVENTION An object of the present invention is to provide a novel laminate board which satisfies the requirements of electrical insulation and low dielectric constant. Another object is to provide a new process for producing a plate applicable to the production of a laminate with none of the disadvantages described above. More specifically, the invention provides a laminate board comprising a center plate which comprises a resin and filler particles uniformly distributed in said resin and sheets provided on both sides of the center plate which comprise resin and reinforcing fabric. When the board is used in a printed circuit board, copper foils are further laminated to it. The plate of this invention is prepared by continuous molding of a mixture comprising a resin and a filler, wherein the mixture of resin and filler is at least partly solidified while moving through a vertically disposed pass. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a cross-section of an embodiment of the laminate board according to the present invention. FIG. 2 shows a comparative cross-section of a laminate board disclosed in the prior art (Japanese Patent Publication No. 18353/82). FIG. 3 shows a schematic diagram of the process of this invention. FIG. 4 shows a microphotograph of a cross-section of a laminate board of this invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS A typical example of a copper foil-clad laminate board of this invention is shown in FIG. 1. A center plate is sandwiched between impregnated reinforcing fabrics 2 which are covered by copper foils 1. The center plate comprises a resin 3 wherein particles of a filler 4 are distributed uniformly. It is well-known to prepare a continuous plate of a comparatively large thickness by extruding a monomer or polymer from a slit or die, allowing the extruded material to flow on a horizontally moving belt and hardening it by heating or cooling during its passage on the belt. Such method is satisfactory for the preparation of a plate from homogeneous resin liquid such as molten resin or a solution of a resin. However, in the case of a heterogeneous solution like polymer/filler mixture the known extrusion method is not satisfactory. In order to prepare a uniform mixture, it is necessary to use a resin having as low a viscosity as possible. However, the low viscosity of the mixture (less than 10 3 poises) together with the specific gravity difference (of more than 0.2) between the resin and the filler give rise to serious dislocation of the filler during continuous molding of the plate. Consequently, as shown in FIG. 2, asymmetric distribution of the filler 8 in the resin 7 occurs in the direction perpendicular to the surface of the plate (hereafter designated as Z-direction) in each layer between neighboring glass cloths 6. The use of this plate in a printed circuit board clad with copper foils 5 imparts undesirable properties to the board, in particular, bending of the board. This bending is often aggravated by subsequent treatments such as soldering and etching. To prevent asymmetric filler distribution in a plate extruded by the prior art method, it is necessary to reduce the thickness of the layer of resin/filler mixture in order to bring the filler in close contact with the reinforcing fabric 2 and thereby prevent movement of the filler in the resin. This means that the adjacent reinforcing fabrics must be brought into contact with each other and, accordingly, only a small amount of filler can be used. Furthermore, because in practice the particle size distribution of the filler is very large, it is not possible to prevent movement of the smaller filler particles. FIG. 3 shows a schematic diagram of the process of this invention. A mixture 9 of a resin and a filler is extruded from a slit 10 to flow onto vertical double belt press 11. By this arrangement, the filler does not move in the horizontal direction (Z-direction) even when the difference in specific gravity between the resin and the filler is large. The mixture is hardened by heating or cooling while it is passing between the pair of belts. The plate, which is partially hardened but retains some plasticity, is conveyed by roll 12 which changes the direction of the movement of the plate from vertical to horizontal. In order to prevent the plate from breaking upon being bent around the roll, the size of the roll is selected according to the hardness of the plate. Thus, the harder the plate, the larger the roll. Upon leaving the roll 12, the plate is conveyed on a horizontal double belt press 13. At this point, the filler neither sinks nor floats to cause asymmetric distribution, since the resin has hardened sufficiently to prevent movement of the filler particles. In the present invention, thermosetting resins such as phenol, epoxy, furane, unsaturated polyester, xylene, alkyd, sulfonic amide, melamine resins, and thermoplastic resins such as polyamide, polyester, polyolefin, polystyrene, polyphenylene oxide, polyphenylene sulfide, polysulfone, polyethersulfone, polyetherimide, polyacetal, polycarbonate, polyvinylidene fluoride and polyacrylate resins may be used. The resin of the center plate is not necessarily the same as that of the sheets to be laminated on the center plate. The filler material is selected according to the required properties of the board. For example, for the purpose of lowering the dielectric constant, it is advantageous to use hollow microspheres of alumina, silica, zirconia, glass, carbon and phenol resin. The preferred filler in this case consists of hollow glass microspheres of 20-150 μm in diameter having a glass thickness 0.5-2 micro meters. The volume fraction of filler based on the total volume of the center plate should be 0.3 to 0.8, more preferably 0.5 to 0.7. As the reinforcing fabric, woven and non-woven sheets made of inorganic or organic fibers, preferably glass fiber, quartz fiber, polyaramid fiber "Kevlar" may be used. This invention is particularly useful in situations where the difference in specific gravity between the resin and the filler is large, especially more than 0.5, were the viscosity of the resin to be mixed is low, especially less than 10 2 poises, and further, where the size of the filler particles is relatively large (more than 5 microns). For example, in practical applications, there are many cases where a resin must be used which has a viscosity of less than 10 poise. EXAMPLE 1 Epoxy resin composition was prepared with 100 parts of diglycidyl ether of Bisphenol A ("EPIKOTE" 828: YUKA SHELL CO.), 86 parts of methyl hexahydrophthalic anhydride ("EPICLON" B650: DAINIHON INK CO.) and 1 part of dimethylbenzylamine (Parts refer to parts by weight). This epoxy resin composition has a viscosity of 5 poises at 25° C. Glass microsphere ("GLASS BUBBLES" B38/4000: 3M INC.) of 50 micro meters in average diameter and specific gravity 0.38 was used as a filler. A mixture was obtained by mixing the epoxy resin composition and the glass microspheres in a volume ratio of 40/60 at room temperature. The mixture was allowed to defoam in vacuum. Then it was extruded from a slit onto a vertically disposed moving double belt press of 2 meter long, as shown in FIG. 3. The speed of the pair of moving belts was 8 meters/hour. The temperature of the belt was kept at 150° C. After passing through the vertically disposed belt, the almost fully hardened plate was moved along a roll of 900 mm diameter to change its direction from vertical to horizontal. Then, the plate was moved horizontally by a second double belt press of 2 meter long kept at a temperature of 170° C. As a result, a plate of 15 mm in thickness and of specific gravity 0.80 was obtained. Glass cloth (WE116E: NITTO BOSEKI CO.) of 150 μm thickness was impregnated with the above epoxy resin composition to obtain a sheet (prepreg). A laminate board was prepared by sandwiching the plate between two sheets of prepreg and then between two sheets of copper foil as in FIG. 1 by use of a conventional heating press. The properties of the board are shown in Table 1 from which it is seen that a laminate board of good performance was obtained. TABLE 1______________________________________Properties of board Comp. Comp. Example 1 Ex. 1 Ex. 2______________________________________Thickness (mm) 1.60 1.63 1.60Er (1 MHz) 2.5 2.6 2.7tan δ (1 MHz) 0.010 0.015 0.020Insulation Resistance (Ω) 5.6 × 10.sup.9 1.5 × 10.sup.7 3.5 × 10.sup.9Bending (%) 0.0 0.7 1.5______________________________________ Index of bending was evaluated according to the standard test method. (IPCTM-650). COMPARATIVE EXAMPLE 1 Using the same materials (epoxy resin composition, hollow microsphere and glass cloth) as in Example 1, a prepreg was produced by ordinary impregnation according to a prior art method (Tokko-sho 57-18353). A board was obtained by laminating six sheets of the prepreg and two sheets of copper foil by use of heating press. FIG. 2 shows the schematic diagram of the board obtained. Table 1 shows the properties of this board as compared with the board of Example 1. It can be seen that the electrical insulation resistance of this board is small and its bending is a little larger than observed in the board of Example 1. COMPARATIVE EXAMPLE 2 Using the same materials as in Example 1, the epoxy resin composition and glass hollow microspheres were mixed. The mixture was extruded from a slit onto a horizontal double belt press. The speed of the moving belt was 8 meters/hr and its temperature was kept at 150° C. A copper-clad laminate board was obtained in the same manner as in Example 1. The properties of this board are shown in the third column of Table 1. It can be seen that the bending of this board is considerably larger than was observed in Example 1.
A copper clad laminate board for a printed circuit has a center plate which is a thermosetting resin containing hollow glass microspheres uniformly distributed in the resin. The center plate has sheets provided on both sides thereof, which sheets are a thermosetting resin having a reinforcing fabric. The board has a high electrical resistance and resists bending during subsequent processing.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "This is a division of application Ser.", "No. 765,476 filed Aug. 14, 1985 now U.S. Pat. No. 4,661,301 issued Apr. 28, 1987.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention conerns a laminate board which is applicable to the manufacture of a printed circuit board and a process for continuous molding of a plate for use in producing the laminate board.", "Description of the Prior Art It is well-known that a material having a low dielectric constant (Er) and dissipation factor (tan δ) is advantageous for use in printed circuit boards.", "As the dielectric constant goes down, the electric performance, as measured by time delay, capacitance, and other factors, is improved.", "Many materials having a low dielectric constant, such as polyethylene, poly 4-methyl pentene-1, polystyrene, polytetrafluoroethylene are not necessarily suitable for use in printed circuit boards from the viewpoints of heat resistance, cost or processability.", "Incorporation of a filler into a resin is a well-known technique for improving properties of the resin such as electric, optical, mechanical, electromagnetic, frictional, chemical and other properties.", "One method for lowering the dielectric constant of a material is to incorporate a filler such as one consisting of hollow microspheres, as disclosed in Japanese Patent Publication No. 18353/82 (Tokko-sho 57-18353);", "and F. W. Haining &", "D. G. Herbaugh, IBM TECH.", "DISCLOSURE BULL (USA) Vol. 22.", "No. 5, 1799, October 1979.", "The glass epoxy laminates prepared by conventional processes according to the above method using epoxy/microsphere prepregs, however, do not necessarily perform well in a printed circuit board.", "For example, the board's deviation from flatness, such as bending and twisting causes problems in subsequent treatments such as soldering, etching, drilling, laminating of resist, and plating.", "These defects may be due to uneven distribution of the filler in the prepregs.", "Furthermore, the electrical insulation of the board is not as large as is required when the board is immersed in boiling water.", "Voids formed between the filler and the reinforcing fabric are considered responsible for these disadvantages.", "SUMMARY OF THE INVENTION An object of the present invention is to provide a novel laminate board which satisfies the requirements of electrical insulation and low dielectric constant.", "Another object is to provide a new process for producing a plate applicable to the production of a laminate with none of the disadvantages described above.", "More specifically, the invention provides a laminate board comprising a center plate which comprises a resin and filler particles uniformly distributed in said resin and sheets provided on both sides of the center plate which comprise resin and reinforcing fabric.", "When the board is used in a printed circuit board, copper foils are further laminated to it.", "The plate of this invention is prepared by continuous molding of a mixture comprising a resin and a filler, wherein the mixture of resin and filler is at least partly solidified while moving through a vertically disposed pass.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a cross-section of an embodiment of the laminate board according to the present invention.", "FIG. 2 shows a comparative cross-section of a laminate board disclosed in the prior art (Japanese Patent Publication No. 18353/82).", "FIG. 3 shows a schematic diagram of the process of this invention.", "FIG. 4 shows a microphotograph of a cross-section of a laminate board of this invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS A typical example of a copper foil-clad laminate board of this invention is shown in FIG. 1. A center plate is sandwiched between impregnated reinforcing fabrics 2 which are covered by copper foils 1.", "The center plate comprises a resin 3 wherein particles of a filler 4 are distributed uniformly.", "It is well-known to prepare a continuous plate of a comparatively large thickness by extruding a monomer or polymer from a slit or die, allowing the extruded material to flow on a horizontally moving belt and hardening it by heating or cooling during its passage on the belt.", "Such method is satisfactory for the preparation of a plate from homogeneous resin liquid such as molten resin or a solution of a resin.", "However, in the case of a heterogeneous solution like polymer/filler mixture the known extrusion method is not satisfactory.", "In order to prepare a uniform mixture, it is necessary to use a resin having as low a viscosity as possible.", "However, the low viscosity of the mixture (less than 10 3 poises) together with the specific gravity difference (of more than 0.2) between the resin and the filler give rise to serious dislocation of the filler during continuous molding of the plate.", "Consequently, as shown in FIG. 2, asymmetric distribution of the filler 8 in the resin 7 occurs in the direction perpendicular to the surface of the plate (hereafter designated as Z-direction) in each layer between neighboring glass cloths 6.", "The use of this plate in a printed circuit board clad with copper foils 5 imparts undesirable properties to the board, in particular, bending of the board.", "This bending is often aggravated by subsequent treatments such as soldering and etching.", "To prevent asymmetric filler distribution in a plate extruded by the prior art method, it is necessary to reduce the thickness of the layer of resin/filler mixture in order to bring the filler in close contact with the reinforcing fabric 2 and thereby prevent movement of the filler in the resin.", "This means that the adjacent reinforcing fabrics must be brought into contact with each other and, accordingly, only a small amount of filler can be used.", "Furthermore, because in practice the particle size distribution of the filler is very large, it is not possible to prevent movement of the smaller filler particles.", "FIG. 3 shows a schematic diagram of the process of this invention.", "A mixture 9 of a resin and a filler is extruded from a slit 10 to flow onto vertical double belt press 11.", "By this arrangement, the filler does not move in the horizontal direction (Z-direction) even when the difference in specific gravity between the resin and the filler is large.", "The mixture is hardened by heating or cooling while it is passing between the pair of belts.", "The plate, which is partially hardened but retains some plasticity, is conveyed by roll 12 which changes the direction of the movement of the plate from vertical to horizontal.", "In order to prevent the plate from breaking upon being bent around the roll, the size of the roll is selected according to the hardness of the plate.", "Thus, the harder the plate, the larger the roll.", "Upon leaving the roll 12, the plate is conveyed on a horizontal double belt press 13.", "At this point, the filler neither sinks nor floats to cause asymmetric distribution, since the resin has hardened sufficiently to prevent movement of the filler particles.", "In the present invention, thermosetting resins such as phenol, epoxy, furane, unsaturated polyester, xylene, alkyd, sulfonic amide, melamine resins, and thermoplastic resins such as polyamide, polyester, polyolefin, polystyrene, polyphenylene oxide, polyphenylene sulfide, polysulfone, polyethersulfone, polyetherimide, polyacetal, polycarbonate, polyvinylidene fluoride and polyacrylate resins may be used.", "The resin of the center plate is not necessarily the same as that of the sheets to be laminated on the center plate.", "The filler material is selected according to the required properties of the board.", "For example, for the purpose of lowering the dielectric constant, it is advantageous to use hollow microspheres of alumina, silica, zirconia, glass, carbon and phenol resin.", "The preferred filler in this case consists of hollow glass microspheres of 20-150 μm in diameter having a glass thickness 0.5-2 micro meters.", "The volume fraction of filler based on the total volume of the center plate should be 0.3 to 0.8, more preferably 0.5 to 0.7.", "As the reinforcing fabric, woven and non-woven sheets made of inorganic or organic fibers, preferably glass fiber, quartz fiber, polyaramid fiber "Kevlar"", "may be used.", "This invention is particularly useful in situations where the difference in specific gravity between the resin and the filler is large, especially more than 0.5, were the viscosity of the resin to be mixed is low, especially less than 10 2 poises, and further, where the size of the filler particles is relatively large (more than 5 microns).", "For example, in practical applications, there are many cases where a resin must be used which has a viscosity of less than 10 poise.", "EXAMPLE 1 Epoxy resin composition was prepared with 100 parts of diglycidyl ether of Bisphenol A ("EPIKOTE"", "828: YUKA SHELL CO.), 86 parts of methyl hexahydrophthalic anhydride ("EPICLON"", "B650: DAINIHON INK CO.) and 1 part of dimethylbenzylamine (Parts refer to parts by weight).", "This epoxy resin composition has a viscosity of 5 poises at 25° C. Glass microsphere ("GLASS BUBBLES"", "B38/4000: 3M INC.) of 50 micro meters in average diameter and specific gravity 0.38 was used as a filler.", "A mixture was obtained by mixing the epoxy resin composition and the glass microspheres in a volume ratio of 40/60 at room temperature.", "The mixture was allowed to defoam in vacuum.", "Then it was extruded from a slit onto a vertically disposed moving double belt press of 2 meter long, as shown in FIG. 3. The speed of the pair of moving belts was 8 meters/hour.", "The temperature of the belt was kept at 150° C. After passing through the vertically disposed belt, the almost fully hardened plate was moved along a roll of 900 mm diameter to change its direction from vertical to horizontal.", "Then, the plate was moved horizontally by a second double belt press of 2 meter long kept at a temperature of 170° C. As a result, a plate of 15 mm in thickness and of specific gravity 0.80 was obtained.", "Glass cloth (WE116E: NITTO BOSEKI CO.) of 150 μm thickness was impregnated with the above epoxy resin composition to obtain a sheet (prepreg).", "A laminate board was prepared by sandwiching the plate between two sheets of prepreg and then between two sheets of copper foil as in FIG. 1 by use of a conventional heating press.", "The properties of the board are shown in Table 1 from which it is seen that a laminate board of good performance was obtained.", "TABLE 1______________________________________Properties of board Comp.", "Comp.", "Example 1 Ex.", "1 Ex.", "2______________________________________Thickness (mm) 1.60 1.63 1.60Er (1 MHz) 2.5 2.6 2.7tan δ (1 MHz) 0.010 0.015 0.020Insulation Resistance (Ω) 5.6 × 10.", "sup[.", "].9 1.5 × 10.", "sup[.", "].7 3.5 × 10.", "sup[.", "].9Bending (%) 0.0 0.7 1.5______________________________________ Index of bending was evaluated according to the standard test method.", "(IPCTM-650).", "COMPARATIVE EXAMPLE 1 Using the same materials (epoxy resin composition, hollow microsphere and glass cloth) as in Example 1, a prepreg was produced by ordinary impregnation according to a prior art method (Tokko-sho 57-18353).", "A board was obtained by laminating six sheets of the prepreg and two sheets of copper foil by use of heating press.", "FIG. 2 shows the schematic diagram of the board obtained.", "Table 1 shows the properties of this board as compared with the board of Example 1.", "It can be seen that the electrical insulation resistance of this board is small and its bending is a little larger than observed in the board of Example 1.", "COMPARATIVE EXAMPLE 2 Using the same materials as in Example 1, the epoxy resin composition and glass hollow microspheres were mixed.", "The mixture was extruded from a slit onto a horizontal double belt press.", "The speed of the moving belt was 8 meters/hr and its temperature was kept at 150° C. A copper-clad laminate board was obtained in the same manner as in Example 1.", "The properties of this board are shown in the third column of Table 1.", "It can be seen that the bending of this board is considerably larger than was observed in Example 1." ]
FIELD OF THE INVENTION The present invention relates to an implementation of a content addressable memory (CAM) for a W-bit keyword and N possible matching addresses by using a random access memory (RAM) and the input keyword to address the memory locations of said RAM. It further relates to methods for operating said implementation, including the use as a specific type of CAM known as functional memory (FM). The term implementation is defined as the realization of a system design in hardware, software, or both. BACKGROUND OF THE INVENTION In the field of computer techniques basically two different types of memories are found with regard to the access to stored data. In case of the first type, the stored data are read by addressing a memory location within the memory by its number. Usually, such a memory chip shows separate address lines and data lines. To search data from such a memory, the exact address of this data has to be known. The addressed, stored data is then connected to the data lines. To this category of storage devices belong the random access memory (RAM) and the read only memory (ROM). Though this storage principle became common and appears nowadays in virtually every complex electronic device, the random access presents only a limited solution to the access requirements of many problems involving large amounts of data or fast access to certain data sets. For many applications, therefore, a name or object oriented approach to a memory location appears to be advantageous. This storage principle is represented by the content addressable memories (CAM), also known as associative memories. These memories are labeled content or data driven, as they make use of the input word (keyword) to find all the information associated with that key. In general, the result of the input of an keyword is a match or coincidence indication of some stored words. The match or coincidence indication appears as activation of a matching line used for subsequent operations. Content addressed devices allow to perform a search after a keyword in a parallel mode, in which all stored words are compared with the keyword simultaneously. Therefore, the use of CAM gives in many applications (except purely numerical) a significant gain in speed, which has to be paid on the other hand by higher costs per bit. A special implementation of a CAM is known as functional memory (FM). The functional memory allows to set single bits of a stored word into a "don't-care" state being irrelevant to the matching or coincidence function. The bits of a word stored in a FM can, thus, take a third state, besides the logical 0 and 1. In conventional FM designs, the don't-care state is, for example, implemented by using flip-flops blocking the access to certain bits. If the matching lines are not designed to address any following devices directly, often priority encoders follow to handle multiple matches. This is done by ordering the matches into a sequence according to a priority scheme. CAMs have found many fields of application including protocol processing units in information networks, where a packet of data includes an address, which is used as the keyword for the CAM. The CAM, then, indicates the address to which the data are to be directed. Other applications are found in parallel processing to manage access to storage devices and processors common to all units. Further fields of application are data or demand driven computer architectures, and database engines, specially designed to handle the access to databases. Since CAMs do have the above mentioned advantages, numerous ways of implementation have been suggested. Usually, the CAM implementation by semiconducting devices requires a special chip design resulting in a higher number of transistors per bit and a higher number of pins compared to the standard RAM devices. An advanced example of this approach is described in EP-A-0183885. However, in many cases the special design of the CAMs prevents their use in otherwise conventionally designed circuits, like programmable gate arrays. A closer definition of the technical field of the invention is provided by the efforts to implement CAM using conventional random access memory. Examples for these methods or the resulting devices, respectively, may be found in EP-A-0228917, EP-A-0459703, or in the international application WO 90/04849. The underlying principle of these known techniques is a sequential comparison of the keyword with the stored data. The sequential comparison, however, deteriorates the speed of search, i.e. the main advantage of the content addressable memory. Therefore, the current invention does not make use of a sequential comparison of the stored words with the keyword, but is instead based on directly addressing the memory location at which an appropriate destination is stored by at least a part of the keyword. This technique, described for example by T.-B. Pei et al., IEEE INFOCOM 1991. Proceedings of the 10th Annual Joint Conference of the IEEE Computer and Communication Societies, New York, 1991,0515-0524, is appropriate due to its speed and simplicity only if the width of a keyword is small. As modern applications often demand keywords having a data width of 16 bits and more, this simple approach is no longer feasible. OBJECTS OF THE INVENTION It is, therefore, an object of the invention to provide a method for implementing CAM with RAMs. More specifically, it is an object of the invention to introduce a CAM implementation with high search speed and to overcome the address space limitation of known approaches. SUMMARY OF THE INVENTION To implement a content addressable memory (CAM) with an input word size or keyword width of W bits and N output lines according to the invention, m subsets of the keyword are used to address m random access memories (RAMs). The subsets of the keyword preferably have a width of W/m bits. Each RAM has an output data width of N bits corresponding to the N output lines of the conventional CAM. The RAMs may be of the static (SRAM) or dynamic (DRAM) type. The DRAMs, e.g. video RAM, have the advantage of a smaller number of transistors per memory cell and are preferred to be used with the new implementation, if production costs are considered to be most important. Tile use of SRAMs gives, on the other hand, the advantage of a higher operating speed. After being addressed, these RAMs connect the data stored at the addressed location to the output lines. The m output data are subjected to a boolean AND operation, in which the i-th bit of one output is ANDed with the i-th bit of all others, i being a number between 0 and N-1. This operation is shortly denoted as a bitwise AND. Devices to perform the described operation are known as (bitwise) AND gates. The bitwise AND results in a word of N-bit width having a logical 1 as bit i, only, if all bits i of the m outputs show a 1. The data as stored in the m RAMs secure that a 1 appears at the output line which is assigned to the applied keyword corresponding to the working principles of a known CAM as set out at the beginning of this description. Though being only pad of the stored data, a 1 within the output of the AND operation leads to the activation of a matching line undistinguishable from the the way a regular CAM works. In case that the output word contains more than a single 1, corresponding to a multiple match of the CAM, the matching lines can be fed to a priority encoder. Priority encoder schemes are known to a person skilled in the art. For the sake of shortness, the new implementation according to the invention is defined as RCAM. To generate a match at bit i when applying a certain keyword, therefore, a 1 at each bit i of the m memory locations addressed by the m subsets of keyword has to be stored beforehand. If this word space to be managed by the RCAM, i.e. the data stored within the m RAMs, remains unchanged during application, the use of read only memories (ROMs) in all their variety (EPROM, EEPROM, etc.) is feasible. The term memory unit comprises both types of memory. However, a preferred embodiment of the invention allows a flexible management of the word space of the RCAM: To secure that an input keyword gives a match with a line i at the output, this keyword is applied to the address input of the RAMs and an N bit data word with a 1 as i-th bit is stored at each RAM. The setting of a bit can be done in a read-modify-write cycle, in which the previously stored data is read and updated appropriately by, for example, being connected with an OR operation to another data word which in turn has only the i-th bit set to 1. A more convenient way is to use known bit-addressable RAMs for the implementation. Growable bit-addressable memories and registers being based, for example, on the techniques described in: J. Petrovick Jr. et al., "A 300k-Circuit ASIC Logic Family",Proc. of ISSCC '90, 88-89 (1990), are applied with advantage. The writing procedure described above is only used for an empty RAM, which contains only zeros. To introduce changes in the stored data, the procedure has to be modified. To change the keyword leading to a match at line i, first the old keyword has to be applied 'to the address input and the i-th bit has to be cleared. When the bit has been cleared, the new keyword can be applied in the same manner as described above. This embodiment of the invention includes the application of a memory (control RAM), which serves as storage for the keywords and the bit position(s) to which they match. A preferred method is to store the keyword at a memory location of the control RAM addressed by the correspondent matching line index i. Using this embodiment of the invention, new keywords can be applied to old matching addresses and vice versa resulting in an broader applicability of the new method. Another preferred embodiment of the invention is an implementation of a functional memory (FM). As described above, a functional memory is basically a CAM in which the bits of the stored words can be put into one of three states. The first two are 1 and 0 for the matching with the input key, and the third state is a "don't-care", indicating that said bit is to be ignored in the matching process. According to the invention a don't-care bit is implemented by an extension of the bit setting procedure, as described above for the RCAM. To activate a certain line mi without regard to the k-th bit of the keyword, the k-th bit of the key is set during the writing of the word space once to 1 and once to 0. This generates two different addresses to one of the RAMs. At both memory locations, the i-th bit is set to 1. During the operation of the FM, thus, a match at the i-th bit or matching line m i is established, irrespective of the k-th bit of the input keyword. In general, this implementation requires 2 n storing or writing operations for n don't-care bits in one word. Controlling the change of the stored words, further, requires two bits to store one bit of word complying to the three possible states. Thus, the control RAM is provided with a word width of 2N to control a FM with a word width of N bits. The control RAM becomes superfluous if no change of the word space has to be dealt with in a specific implementation. In this case, the writing procedure can be shortened by loading a precalculated content into the RAMs. The new implementation advantageously allows to increase the number of stored words by using additional, separately controllable address lines of the RAMs, which are not connected to the subset of the keyword. For example, during the start of an associative read, the additional address lines are set to zero. If no match has been found, the additional address is incremented and the matching procedure is repeated. The search is stopped when encountering a match or when all address lines are set to 1. The latter condition may also be valid, if multiple matches are allowed by the following devices. By using n additional address lines the number of words stored in the RCAM is increased by a factor 2 n . The additional address lines of the RAMs may also serve as a implementation of a mask for the input keyword. Such a mask is used in known CAMs to suppress certain bits of the keyword in the whole matching process in contrast to a FM. To implement such a mask in accordance with the invention, an additional address line is used for every address line, which connects the keyword to the RAM. If by a proper writing procedure the word space addressed by the additional lines is completely loaded with 1, a bit of the keyword can be masked by switching from the address line connected with the keyword to its counterpad. Another preferred embodiment of the invention allows to increase the word width, i.e. the number of bits per keyword, by using additional separately controllable address lines and a register. It shows definite advantages, when the keyword is fed to the RCAM not as whole but in sequential blocks. The input of the first part or block of the keywords results in an N-bit word at the output in the same manner as described above. But instead of being directed to the output lines, it is stored in said register. In the next cycle, the additional address is increased by 1 and the following block of the keyword connected to the input of the RCAM. The resulting N-bit data output is bitwise ANDed with the word previously stored in the register. The result is again clocked into the register. This procedure is repeated until the last block of the keyword is applied to the RCAM. In this last cycle, the output word is finally appearing at the matching lines. Thus, a 1 at the i-th bit of the output represents a 1 at the i-th bit of all preceding outputs stored intermediately in the register. As it is convenient to feed back constantly the data stored in the register, it becomes necessary to set all bits of the register to 1 before operating the device. It is obvious to a person skilled in the art that a combination of all described embodiments can be implemented readily. LIST OF THE DRAWINGS The invention is described below by way of example with reference to the drawings, which are schematic and not drawn to scale. They only show the basic devices whereas standard peripheral components are being left out for the sake of simplicity. FIG. 1 (prior art) shows the working principle of a CAM. FIG. 2 sketches the basic elements of the CAM implementation according to the invention and the data flow through them. FIG. 3 shows the use of an additional control RAM. FIG. 4 shows the use of a register to increase the effective bit size of the keyword. FIG. 5 shows the implementation of a functional memory. DETAILED DESCRIPTION OF THE INVENTION In the following, the invention is described in detail with reference to the drawings and the prior ad. The addresses of the memory locations of the shown random access memories correspond to the number of the rows when counted from above. Bit-addressable RAMs have been used throughout. The known concept of a CAM is shown in FIG. 1. The keyword is fed into the CAM, which activates a matching line, when a match is encountered at a memory location (row). Activation usually consists of applying a 1 to a particular output line of the device. The key and the stored data have a width of W bits with W being 6 for the described example. The number of matching lines m o to m N-1 is N. It is assumed that 000110 is stored at row 1. Consequently, a 000110 key input results in an activation of line m 1 . The implementation of such a CAM according to the invention (FIG. 2) is based on using three known bit-addressable RAMs with a 4×N-bit capacity. Thus, four words of N-bit width can be stored. In the following, word and row are used as synonyms. Additional address and control lines have been omitted for the sake of simplicity. In the RAMs, words are stored in such a way that a 1 occurs at the first row of the first RAM, a 1 occurs at the second row of the second RAM, and a third 1 occurs at the third row of the third RAM. The keyword is divided into three subsets of two bits, respectively, by an appropriate division of the keyword input lines. The subsets are applied to the address lines of the RAMs, potentially addressing four rows of the particular memory. The addressed data are applied to the output lines of three RAMs, respectively. The three sets of output data are bitwise ANDed the following gate. The AND operation, thus, results in a N-bit word with a 1 at the bit position where all input data sets (which are the output of the preceding RAMs) show a 1, too. In the example, the keyword 000110 is applied to the RCAM. The subsets of the keyword are 00, 01, and 10, respectively. In FIG. 2 the split data lines are denoted by these subsets. As the first subset of the keyword addresses the first row of the first RAM, a 1 is found as second bit of the data output. The same applies to the second and third RAM, which were addressed by 01 and 10, respectively. The following AND operation results in a N-bit word with 1 as second bit corresponding to an activation of matching line m 1 , as desired. In the second example of the invention (FIG. 3), the RCAM has been extended for changing the data stored in the RAMs and, consequently, the matching line. The extension consists essentially of a fourth RAM acting as control RAM. This control RAM stores the keyword to a certain matching line at the address corresponding to this matching line. Row number and the stored keyword is used to set the bits within the three RAM. To change the keyword activating matching line m 1 from 6 (binary: 000110) to 35 (100011), the matching line number (1) was used to address the control RAM, which, in turn, outputs the old keyword (000110). This word is fed to the address input of the three RAMs via a multiplexer (MUX). The MUX serves as switch between the data coming from the control RAM and the keywords applied during normal operation. The output of all three RAMs is connected to a logic unit (not shown), which clears the second bit each output and restores the remainder. In a following step, 100011 is used to address the three RAMs and the second bit of each output data is updated to 1 and restored in the same way as described above. FIG. 3 shows the the memories in the old and new state, with the latter denoted by brackets. After storing the new data, a 100011, applied as keyword, activates the matching line m 1 . In a third example of the invention, an N-bit register is added to the RCAM, the contents of which is fed back to the AND unit (FIG. 4). Initially, all bits of the register are set to 1. FIG. 4 also shows an additional address line to the RAMs used. The data stored at locations related to a 1 at this address line are put into brackets. Thus, the RAMs shown depict two RAM locations: one at which the data in brackets are stored and one at which the data without brackets are stored. A twelve-bit keyword (000110110011) is connected to the modified RCAM in subsequent portions of 6 bits each. The second portion of the keyword is set into brackets. The first output from the RAM, which are additionally addressed by 0, has a 1 as the second bit. The bitwise ANDing with the content of the register does not lead to a change as it was preloaded with 1 at all bit positions. The N-bit output, having a 1 only as the second bit, is stored in the register and subsequently, the second half of the keyword addresses the RAMs. Simultaneously, the additional address line is switched to 1 giving access to the memory contents in brackets. Again a 1 at the second bit of all three outputs occurs. Bitwise ANDing with the contents of the register provides no change, as the register contained a 1 as second bit from its previous loading. After this, the output is connected to the matching lines activating m 1 . In a fourth example (FIG. 5), the implementation is used as functional memory (FM). As said above, the FM is basically a CAM, which allows to set single bits in the word space into a don't-care state. With regard to FIG. 1 it is assumed that the second bit of the stored word 000110, leading to m 1 , should be set into the don't-care state, i.e. line m 1 is activated without regard to the second bit of the keyword. In other terms, applying 000110 or 010110 both end in a match at m 1 . To implement a functional memory device, the basic structure shown in FIG. 2 is used, together with a modification of writing to the word space of the memories: First the addressing key 010110 is applied, and the second bit of the second word (row) of the first memory is set to 1. In a second writing step, the memories is addressed by 000110, and the second bit the first word (row) of the first memory is set to 1. The writing to the other memories does not change with regard to the first two examples of the invention, as described above. In operation, any keyword of the bit structure 0×0110 (x=0,1) activates matching line m 1 , i.e. this special implementation acts as functional memory.
A content addressable memory (CAM) implementation using random access memory (RAM) and a method for operating the implementation are described, wherein the RAM is divided into smaller, individually addressable units, which are addressed by a subword of the applied keyword, and the outputs of which are bitwise ANDed. The result of the bitwise AND operation is used to activate the matching lines of the CAM implementation. The new implementation allows the use of conventional circuit design.
Briefly describe the main idea outlined in the provided context.
[ "FIELD OF THE INVENTION The present invention relates to an implementation of a content addressable memory (CAM) for a W-bit keyword and N possible matching addresses by using a random access memory (RAM) and the input keyword to address the memory locations of said RAM.", "It further relates to methods for operating said implementation, including the use as a specific type of CAM known as functional memory (FM).", "The term implementation is defined as the realization of a system design in hardware, software, or both.", "BACKGROUND OF THE INVENTION In the field of computer techniques basically two different types of memories are found with regard to the access to stored data.", "In case of the first type, the stored data are read by addressing a memory location within the memory by its number.", "Usually, such a memory chip shows separate address lines and data lines.", "To search data from such a memory, the exact address of this data has to be known.", "The addressed, stored data is then connected to the data lines.", "To this category of storage devices belong the random access memory (RAM) and the read only memory (ROM).", "Though this storage principle became common and appears nowadays in virtually every complex electronic device, the random access presents only a limited solution to the access requirements of many problems involving large amounts of data or fast access to certain data sets.", "For many applications, therefore, a name or object oriented approach to a memory location appears to be advantageous.", "This storage principle is represented by the content addressable memories (CAM), also known as associative memories.", "These memories are labeled content or data driven, as they make use of the input word (keyword) to find all the information associated with that key.", "In general, the result of the input of an keyword is a match or coincidence indication of some stored words.", "The match or coincidence indication appears as activation of a matching line used for subsequent operations.", "Content addressed devices allow to perform a search after a keyword in a parallel mode, in which all stored words are compared with the keyword simultaneously.", "Therefore, the use of CAM gives in many applications (except purely numerical) a significant gain in speed, which has to be paid on the other hand by higher costs per bit.", "A special implementation of a CAM is known as functional memory (FM).", "The functional memory allows to set single bits of a stored word into a "don't-care"", "state being irrelevant to the matching or coincidence function.", "The bits of a word stored in a FM can, thus, take a third state, besides the logical 0 and 1.", "In conventional FM designs, the don't-care state is, for example, implemented by using flip-flops blocking the access to certain bits.", "If the matching lines are not designed to address any following devices directly, often priority encoders follow to handle multiple matches.", "This is done by ordering the matches into a sequence according to a priority scheme.", "CAMs have found many fields of application including protocol processing units in information networks, where a packet of data includes an address, which is used as the keyword for the CAM.", "The CAM, then, indicates the address to which the data are to be directed.", "Other applications are found in parallel processing to manage access to storage devices and processors common to all units.", "Further fields of application are data or demand driven computer architectures, and database engines, specially designed to handle the access to databases.", "Since CAMs do have the above mentioned advantages, numerous ways of implementation have been suggested.", "Usually, the CAM implementation by semiconducting devices requires a special chip design resulting in a higher number of transistors per bit and a higher number of pins compared to the standard RAM devices.", "An advanced example of this approach is described in EP-A-0183885.", "However, in many cases the special design of the CAMs prevents their use in otherwise conventionally designed circuits, like programmable gate arrays.", "A closer definition of the technical field of the invention is provided by the efforts to implement CAM using conventional random access memory.", "Examples for these methods or the resulting devices, respectively, may be found in EP-A-0228917, EP-A-0459703, or in the international application WO 90/04849.", "The underlying principle of these known techniques is a sequential comparison of the keyword with the stored data.", "The sequential comparison, however, deteriorates the speed of search, i.e. the main advantage of the content addressable memory.", "Therefore, the current invention does not make use of a sequential comparison of the stored words with the keyword, but is instead based on directly addressing the memory location at which an appropriate destination is stored by at least a part of the keyword.", "This technique, described for example by T.-B.", "Pei et al.", ", IEEE INFOCOM 1991.", "Proceedings of the 10th Annual Joint Conference of the IEEE Computer and Communication Societies, New York, 1991,0515-0524, is appropriate due to its speed and simplicity only if the width of a keyword is small.", "As modern applications often demand keywords having a data width of 16 bits and more, this simple approach is no longer feasible.", "OBJECTS OF THE INVENTION It is, therefore, an object of the invention to provide a method for implementing CAM with RAMs. More specifically, it is an object of the invention to introduce a CAM implementation with high search speed and to overcome the address space limitation of known approaches.", "SUMMARY OF THE INVENTION To implement a content addressable memory (CAM) with an input word size or keyword width of W bits and N output lines according to the invention, m subsets of the keyword are used to address m random access memories (RAMs).", "The subsets of the keyword preferably have a width of W/m bits.", "Each RAM has an output data width of N bits corresponding to the N output lines of the conventional CAM.", "The RAMs may be of the static (SRAM) or dynamic (DRAM) type.", "The DRAMs, e.g. video RAM, have the advantage of a smaller number of transistors per memory cell and are preferred to be used with the new implementation, if production costs are considered to be most important.", "Tile use of SRAMs gives, on the other hand, the advantage of a higher operating speed.", "After being addressed, these RAMs connect the data stored at the addressed location to the output lines.", "The m output data are subjected to a boolean AND operation, in which the i-th bit of one output is ANDed with the i-th bit of all others, i being a number between 0 and N-1.", "This operation is shortly denoted as a bitwise AND.", "Devices to perform the described operation are known as (bitwise) AND gates.", "The bitwise AND results in a word of N-bit width having a logical 1 as bit i, only, if all bits i of the m outputs show a 1.", "The data as stored in the m RAMs secure that a 1 appears at the output line which is assigned to the applied keyword corresponding to the working principles of a known CAM as set out at the beginning of this description.", "Though being only pad of the stored data, a 1 within the output of the AND operation leads to the activation of a matching line undistinguishable from the the way a regular CAM works.", "In case that the output word contains more than a single 1, corresponding to a multiple match of the CAM, the matching lines can be fed to a priority encoder.", "Priority encoder schemes are known to a person skilled in the art.", "For the sake of shortness, the new implementation according to the invention is defined as RCAM.", "To generate a match at bit i when applying a certain keyword, therefore, a 1 at each bit i of the m memory locations addressed by the m subsets of keyword has to be stored beforehand.", "If this word space to be managed by the RCAM, i.e. the data stored within the m RAMs, remains unchanged during application, the use of read only memories (ROMs) in all their variety (EPROM, EEPROM, etc.) is feasible.", "The term memory unit comprises both types of memory.", "However, a preferred embodiment of the invention allows a flexible management of the word space of the RCAM: To secure that an input keyword gives a match with a line i at the output, this keyword is applied to the address input of the RAMs and an N bit data word with a 1 as i-th bit is stored at each RAM.", "The setting of a bit can be done in a read-modify-write cycle, in which the previously stored data is read and updated appropriately by, for example, being connected with an OR operation to another data word which in turn has only the i-th bit set to 1.", "A more convenient way is to use known bit-addressable RAMs for the implementation.", "Growable bit-addressable memories and registers being based, for example, on the techniques described in: J. Petrovick Jr. et al.", ", "A 300k-Circuit ASIC Logic Family",Proc.", "of ISSCC '90, 88-89 (1990), are applied with advantage.", "The writing procedure described above is only used for an empty RAM, which contains only zeros.", "To introduce changes in the stored data, the procedure has to be modified.", "To change the keyword leading to a match at line i, first the old keyword has to be applied 'to the address input and the i-th bit has to be cleared.", "When the bit has been cleared, the new keyword can be applied in the same manner as described above.", "This embodiment of the invention includes the application of a memory (control RAM), which serves as storage for the keywords and the bit position(s) to which they match.", "A preferred method is to store the keyword at a memory location of the control RAM addressed by the correspondent matching line index i. Using this embodiment of the invention, new keywords can be applied to old matching addresses and vice versa resulting in an broader applicability of the new method.", "Another preferred embodiment of the invention is an implementation of a functional memory (FM).", "As described above, a functional memory is basically a CAM in which the bits of the stored words can be put into one of three states.", "The first two are 1 and 0 for the matching with the input key, and the third state is a "don't-care", indicating that said bit is to be ignored in the matching process.", "According to the invention a don't-care bit is implemented by an extension of the bit setting procedure, as described above for the RCAM.", "To activate a certain line mi without regard to the k-th bit of the keyword, the k-th bit of the key is set during the writing of the word space once to 1 and once to 0.", "This generates two different addresses to one of the RAMs. At both memory locations, the i-th bit is set to 1.", "During the operation of the FM, thus, a match at the i-th bit or matching line m i is established, irrespective of the k-th bit of the input keyword.", "In general, this implementation requires 2 n storing or writing operations for n don't-care bits in one word.", "Controlling the change of the stored words, further, requires two bits to store one bit of word complying to the three possible states.", "Thus, the control RAM is provided with a word width of 2N to control a FM with a word width of N bits.", "The control RAM becomes superfluous if no change of the word space has to be dealt with in a specific implementation.", "In this case, the writing procedure can be shortened by loading a precalculated content into the RAMs. The new implementation advantageously allows to increase the number of stored words by using additional, separately controllable address lines of the RAMs, which are not connected to the subset of the keyword.", "For example, during the start of an associative read, the additional address lines are set to zero.", "If no match has been found, the additional address is incremented and the matching procedure is repeated.", "The search is stopped when encountering a match or when all address lines are set to 1.", "The latter condition may also be valid, if multiple matches are allowed by the following devices.", "By using n additional address lines the number of words stored in the RCAM is increased by a factor 2 n .", "The additional address lines of the RAMs may also serve as a implementation of a mask for the input keyword.", "Such a mask is used in known CAMs to suppress certain bits of the keyword in the whole matching process in contrast to a FM.", "To implement such a mask in accordance with the invention, an additional address line is used for every address line, which connects the keyword to the RAM.", "If by a proper writing procedure the word space addressed by the additional lines is completely loaded with 1, a bit of the keyword can be masked by switching from the address line connected with the keyword to its counterpad.", "Another preferred embodiment of the invention allows to increase the word width, i.e. the number of bits per keyword, by using additional separately controllable address lines and a register.", "It shows definite advantages, when the keyword is fed to the RCAM not as whole but in sequential blocks.", "The input of the first part or block of the keywords results in an N-bit word at the output in the same manner as described above.", "But instead of being directed to the output lines, it is stored in said register.", "In the next cycle, the additional address is increased by 1 and the following block of the keyword connected to the input of the RCAM.", "The resulting N-bit data output is bitwise ANDed with the word previously stored in the register.", "The result is again clocked into the register.", "This procedure is repeated until the last block of the keyword is applied to the RCAM.", "In this last cycle, the output word is finally appearing at the matching lines.", "Thus, a 1 at the i-th bit of the output represents a 1 at the i-th bit of all preceding outputs stored intermediately in the register.", "As it is convenient to feed back constantly the data stored in the register, it becomes necessary to set all bits of the register to 1 before operating the device.", "It is obvious to a person skilled in the art that a combination of all described embodiments can be implemented readily.", "LIST OF THE DRAWINGS The invention is described below by way of example with reference to the drawings, which are schematic and not drawn to scale.", "They only show the basic devices whereas standard peripheral components are being left out for the sake of simplicity.", "FIG. 1 (prior art) shows the working principle of a CAM.", "FIG. 2 sketches the basic elements of the CAM implementation according to the invention and the data flow through them.", "FIG. 3 shows the use of an additional control RAM.", "FIG. 4 shows the use of a register to increase the effective bit size of the keyword.", "FIG. 5 shows the implementation of a functional memory.", "DETAILED DESCRIPTION OF THE INVENTION In the following, the invention is described in detail with reference to the drawings and the prior ad.", "The addresses of the memory locations of the shown random access memories correspond to the number of the rows when counted from above.", "Bit-addressable RAMs have been used throughout.", "The known concept of a CAM is shown in FIG. 1. The keyword is fed into the CAM, which activates a matching line, when a match is encountered at a memory location (row).", "Activation usually consists of applying a 1 to a particular output line of the device.", "The key and the stored data have a width of W bits with W being 6 for the described example.", "The number of matching lines m o to m N-1 is N. It is assumed that 000110 is stored at row 1.", "Consequently, a 000110 key input results in an activation of line m 1 .", "The implementation of such a CAM according to the invention (FIG.", "2) is based on using three known bit-addressable RAMs with a 4×N-bit capacity.", "Thus, four words of N-bit width can be stored.", "In the following, word and row are used as synonyms.", "Additional address and control lines have been omitted for the sake of simplicity.", "In the RAMs, words are stored in such a way that a 1 occurs at the first row of the first RAM, a 1 occurs at the second row of the second RAM, and a third 1 occurs at the third row of the third RAM.", "The keyword is divided into three subsets of two bits, respectively, by an appropriate division of the keyword input lines.", "The subsets are applied to the address lines of the RAMs, potentially addressing four rows of the particular memory.", "The addressed data are applied to the output lines of three RAMs, respectively.", "The three sets of output data are bitwise ANDed the following gate.", "The AND operation, thus, results in a N-bit word with a 1 at the bit position where all input data sets (which are the output of the preceding RAMs) show a 1, too.", "In the example, the keyword 000110 is applied to the RCAM.", "The subsets of the keyword are 00, 01, and 10, respectively.", "In FIG. 2 the split data lines are denoted by these subsets.", "As the first subset of the keyword addresses the first row of the first RAM, a 1 is found as second bit of the data output.", "The same applies to the second and third RAM, which were addressed by 01 and 10, respectively.", "The following AND operation results in a N-bit word with 1 as second bit corresponding to an activation of matching line m 1 , as desired.", "In the second example of the invention (FIG.", "3), the RCAM has been extended for changing the data stored in the RAMs and, consequently, the matching line.", "The extension consists essentially of a fourth RAM acting as control RAM.", "This control RAM stores the keyword to a certain matching line at the address corresponding to this matching line.", "Row number and the stored keyword is used to set the bits within the three RAM.", "To change the keyword activating matching line m 1 from 6 (binary: 000110) to 35 (100011), the matching line number (1) was used to address the control RAM, which, in turn, outputs the old keyword (000110).", "This word is fed to the address input of the three RAMs via a multiplexer (MUX).", "The MUX serves as switch between the data coming from the control RAM and the keywords applied during normal operation.", "The output of all three RAMs is connected to a logic unit (not shown), which clears the second bit each output and restores the remainder.", "In a following step, 100011 is used to address the three RAMs and the second bit of each output data is updated to 1 and restored in the same way as described above.", "FIG. 3 shows the the memories in the old and new state, with the latter denoted by brackets.", "After storing the new data, a 100011, applied as keyword, activates the matching line m 1 .", "In a third example of the invention, an N-bit register is added to the RCAM, the contents of which is fed back to the AND unit (FIG.", "4).", "Initially, all bits of the register are set to 1.", "FIG. 4 also shows an additional address line to the RAMs used.", "The data stored at locations related to a 1 at this address line are put into brackets.", "Thus, the RAMs shown depict two RAM locations: one at which the data in brackets are stored and one at which the data without brackets are stored.", "A twelve-bit keyword (000110110011) is connected to the modified RCAM in subsequent portions of 6 bits each.", "The second portion of the keyword is set into brackets.", "The first output from the RAM, which are additionally addressed by 0, has a 1 as the second bit.", "The bitwise ANDing with the content of the register does not lead to a change as it was preloaded with 1 at all bit positions.", "The N-bit output, having a 1 only as the second bit, is stored in the register and subsequently, the second half of the keyword addresses the RAMs. Simultaneously, the additional address line is switched to 1 giving access to the memory contents in brackets.", "Again a 1 at the second bit of all three outputs occurs.", "Bitwise ANDing with the contents of the register provides no change, as the register contained a 1 as second bit from its previous loading.", "After this, the output is connected to the matching lines activating m 1 .", "In a fourth example (FIG.", "5), the implementation is used as functional memory (FM).", "As said above, the FM is basically a CAM, which allows to set single bits in the word space into a don't-care state.", "With regard to FIG. 1 it is assumed that the second bit of the stored word 000110, leading to m 1 , should be set into the don't-care state, i.e. line m 1 is activated without regard to the second bit of the keyword.", "In other terms, applying 000110 or 010110 both end in a match at m 1 .", "To implement a functional memory device, the basic structure shown in FIG. 2 is used, together with a modification of writing to the word space of the memories: First the addressing key 010110 is applied, and the second bit of the second word (row) of the first memory is set to 1.", "In a second writing step, the memories is addressed by 000110, and the second bit the first word (row) of the first memory is set to 1.", "The writing to the other memories does not change with regard to the first two examples of the invention, as described above.", "In operation, any keyword of the bit structure 0×0110 (x=0,1) activates matching line m 1 , i.e. this special implementation acts as functional memory." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation application of co-pending U.S. Ser. No. 12/546,968, filed Aug. 25, 2009, which is a continuation application of U.S. patent application Ser. No. 10/718,195, filed Nov. 20, 2003, which is a continuation application of U.S. patent application Ser. No. 10/670,032, filed Sep. 24, 2003, now abandoned, which is a continuation application of U.S. patent application Ser. No. 10/165,373, filed Jun. 6, 2002, now U.S. Pat. No. 6,702,787, which is a continuation application of U.S. patent application Ser. No. 09/527,955, filed Mar. 9, 2000, now abandoned, which is a continuation application of International Patent Application No. PCT/US98/08968, filed May 1, 1998, which claims priority from U.S. Provisional Patent Application No. 60/045,412, filed May 2, 1997, now expired. BACKGROUND [0002] 1. Technical Field [0003] The present disclosure relates to seal systems of the type adapted to allow the introduction of a surgical instrument into a patient's body. In particular, the disclosure relates to a seal system to be used in combination with a cannula assembly where the cannula assembly is intended for insertion into a patient's body and an instrument is inserted into the patient's body through the cannula. [0004] 2. Background of the Related Art [0005] Laparoscopic procedures are performed in the interior of the abdomen through a small incision, e.g., through narrow endoscopic tubes or cannulas inserted through a small entrance incision in the skin. Minimally invasive procedures are performed elsewhere in the body, e.g., in the chest, and are often generally referred to as “endoscopic” procedures. Minimally invasive or endoscopic procedures generally require that any instrumentation inserted into the body be sealed, i.e. provisions must be made to ensure that gases do not enter or exit the body through the endoscopic incision as, for example, in surgical procedures in which the surgical region is insufflated. Moreover, endoscopic procedures often require the surgeon to act on organs, tissues, and vessels far removed from the incision, thereby requiring that any instruments used in such procedures be relatively long and narrow. [0006] For such procedures, the introduction of a tube into certain anatomical cavities such as the abdominal cavity is usually accomplished by use of a system incorporating a trocar and cannula assembly. A cannula assembly is formed of a cannula attached to a cannula housing which generally includes seal assembly adapted to maintain a seal across the opening of the seal assembly both with and without an instrument inserted therethrough. Since the cannula is in direct communication with the internal portion of the seal assembly, insertion of the cannula into an opening in the patient's body so as to reach the inner abdominal cavity should be adapted to maintain a fluid tight interface between the abdominal cavity and the outside atmosphere. [0007] Since minimally invasive surgical procedures in the abdominal cavity of the body generally require insufflating gases to raise the cavity wall away from vital organs, the procedure is usually initiated by use of a Verres needle through which a gas is introduced into the body cavity. The gas provides a slight pressure which raises the wall surface of the peritoneum away from the vital organs thereby providing an adequate region in which to operate. Thereafter, a trocar assembly which includes a cannula and a trocar or obturator is inserted within the cannula to puncture the peritoneum, i.e. the inner lining of the abdominal cavity wall. The obturator is removed and laparoscopic or endoscopic surgical instruments may then be inserted through the cannula to perform surgery within the abdominal cavity. The cannula may also be utilized for introducing tubes into the body as for drainage purposes, for specimen removal, for diagnostic evaluations, or the like. [0008] In view of the need to maintain the atmospheric integrity of the inner area of the cavity, a seal assembly for a cannula which permits introduction of an obturator and a wide range of surgical instruments and which maintains the atmospheric integrity of the inner area of the cavity is desirable. Generally, in the context of insufflatory, minimally invasive surgical procedures, cannula assemblies include structure(s) that satisfy two sealing requirements. The first requirement is to provide a substantially fluid tight seal when an instrument is not present in the cannula. The second requirement is to provide a substantially fluid tight seal when an instrument is being introduced into or already is present in the cannula. In this regard, there have been a number of attempts in the prior art to provide such sealing requirements. [0009] U.S. Pat. No. 4,655,752 to Honkanen, et al. teaches a cannula including a housing and first and second seal members. The first seal member is conically tapered toward the bottom of the housing and has a circular opening in its center, while the second seal is conically tapered and cup shaped. The second seal includes at least one slit to allow for the passage of instruments. [0010] U.S. Pat. No. 4,929,235 to Merry, et al. teaches a self-sealing catheter introducer having a sealing mechanism to prevent blood or fluid leakage. The sealing mechanism includes a planar sealing element having a slit and a conical sealing element. The sealing elements are each adapted to surround a tube. [0011] U.S. Pat. Nos. 4,874,377 and 5,064,416 to Newgard, et al. relate to a self-occluding intravascular cannula assembly in which an elastomeric valving member is positioned transversely to a housing and is peripherally compressed to cause displacement, distortion and/or rheological flow of the elastomeric material. A frustoconical dilator projection cooperates with the elastomeric valving member in moving the valving member to a non-occluding position. [0012] U.S. Pat. No. 5,300,033 to Miller suggests a valve construction including an elastic body having a cylindrical wall with first and second walls formed integrally with the cylindrical wall. The second wall includes a slit to permit passage of a surgical instrument and first and second leaflets which define the slit. The leaflets are thicker in cross section to provide an additional closing force at the slit. [0013] A disadvantage of several known seal systems for cannulas concerns the difficulty encountered in inserting and advancing the surgical instrument through the seal unit. In particular, since known elastomeric seal members are designed to form and maintain a fluid tight seal about the instrument, the aperture or slit within the seal through which the instrument is passed is of relatively small or narrow dimension. Further, portions of the seal member defining the aperture are generally thick in cross-section to provide a sufficient closing force of the seal about the instrument. See, e.g., U.S. Pat. No. 5,300,033. As a consequence of these design considerations, the level of force needed to insert and advance the instrument through the seal aperture is increased, thereby requiring awkward maneuvering on the surgeon's behalf to appropriately position the instrument for the desired surgery. Moreover, known seal systems are generally ineffectual in accommodating instruments of differing diameter while maintaining acceptable insertion forces and facilitating the range of desired surgical manipulations, e.g., angular instrument movements and specimen removal. [0014] Accordingly, the present disclosure obviates the disadvantages of the prior art by providing a seal unit or assembly for a cannula assembly, which is capable of forming and maintaining a tight seal about instruments of varying diameters inserted through the cannula and which incorporates structure to enhance and facilitate passage of the instrument through the seal unit. SUMMARY [0015] The present disclosure provides a seal assembly for reception of an elongated surgical instrument, which comprises a body having at least one opening configured and dimensioned to permit entry of an elongated surgical instrument and defining a central longitudinal axis; a seal member formed of a resilient material and defining an aperture therein, the aperture being configured and dimensioned such that insertion of the surgical instrument into the aperture causes the resilient material defining the aperture to resiliently contact the outer surface of the surgical instrument in a substantially fluid tight manner; and a fabric layer juxtaposed relative to the resilient material. [0016] The seal assembly may further include a coating applied to the seal member to reduce friction between the seal member and surgical instrumentation inserted therein. The coating is preferably a hydrocyclosiloxane membrane prepared by plasma polymerization process. [0017] In one aspect of the presently disclosed seal assembly a ring member is secured to the seal member and includes a dampening element disposed between a surface of the ring member and a surface of the body. BRIEF DESCRIPTION OF THE DRAWINGS [0018] Various embodiments are described herein below with reference to the drawings wherein: [0019] FIG. 1 is a perspective view of one embodiment of a seal assembly constructed in accordance with the present disclosure; [0020] FIG. 2 is a perspective view with parts separated showing the various structural components of the seal assembly embodiment of FIG. 1 ; [0021] FIG. 3 is a perspective view of a fabric portion for incorporation into the seal element of the embodiment of FIG. 1 ; [0022] FIG. 4 is a cross-sectional view taken along section line 4 - 4 of FIG. 3 ; [0023] FIG. 5 is a perspective view of a fully formed seal member for the seal assembly of FIG. 1 ; [0024] FIG. 6 is a cross-sectional view taken along section line 6 - 6 of FIG. 5 ; [0025] FIG. 6A is an alternative embodiment of the seal element of FIG. 6 ; [0026] FIG. 7 is a cross-sectional view of the seal assembly of FIG. 1 ; [0027] FIG. 8 is a perspective view of a trocar assembly having the seal assembly of FIG. 1 removably installed thereon; [0028] FIG. 9 is a partial cross-sectional view showing the seal body housing taken along section line 9 - 9 of FIG. 8 ; [0029] FIG. 10 is an alternative embodiment of the seal assembly of the present disclosure; [0030] FIG. 11 is a cross-sectional view of a further embodiment of the seal assembly constructed in accordance with the present disclosure; [0031] FIG. 12 is a perspective view of the seal assembly of FIG. 11 ; [0032] FIG. 13 is a perspective view with parts separated of the seal assembly embodiment of FIG. 11 ; [0033] FIG. 14 is a cross-sectional view of a further embodiment of the seal assembly constructed in accordance with the present disclosure; and [0034] FIG. 15 is a perspective view of the seal member of the seal assembly of FIG. 14 . DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS [0035] Referring now in detail to the drawing figures in which like reference numerals identify similar or identical elements, a first embodiment of the seal assembly of the present disclosure is illustrated in FIGS. 1-9 , and is designated generally as seal assembly 100 . [0036] The presently disclosed seal assembly embodiments contemplate the introduction of various types of surgical instruments adapted for insertion through an elongated trocar assembly. Examples of such instruments include clip appliers, graspers, dissectors, retractors, staplers, laser fibers, photographic devices, endoscopes and laparoscopes, tubes, and the like. Such instruments are collectively referred to herein as “instruments”. [0037] Referring to FIG. 2 , seal assembly 100 includes a seal member 118 disposed within the seal assembly body or housing components 114 and 116 which snap fit together by way of flexible tab portions 114 a being deflected upon insertion into receiving openings (not shown) formed in housing component 116 . Seal member 118 has a circular array of holes formed therethrough around the periphery of an inner section 118 b. [0038] A two part ring assembly which includes ring members 120 and 122 are snap fitted together on either side of seal member 118 . Ring member 120 is disposed adjacent the distally facing surface of seal member 118 and ring member 122 is disposed on the proximally facing side of seal member 118 . Ring 120 is provided with holes 120 a and posts 120 b which are alternately disposed around the ring and are aligned with holes 118 a on seal member 118 . Ring 122 is provided with posts 122 a and holes 122 b which mate with holes 120 a and posts 120 b of ring member 120 , respectively by snap fitting together thereby surrounding inner section 118 b . Although rings 120 and 122 are shown having alternating holes and posts, one of the rings could have all holes formed therein while the other ring could have all posts aligned with the holes of the other ring. Additionally, greater or fewer holes and posts may be utilized to secure the two rings together. [0039] A seal clamp 124 is provided within the housing component 114 and 116 and serves to secure the outer periphery of seal member 118 within seal assembly 100 (as best shown in FIG. 7 ). Seal clamp 124 is provided with four projecting posts 124 a which fit within openings ( FIG. 7 ) formed on the proximal side of lower housing 116 . Seal clamp 124 also serves to secure a proximal flange of a lower seal 126 which is provided at the distal end of lower housing member 116 . Lower seal 126 assists in the securement of seal assembly 100 to cannula assembly 110 . [0040] Referring now to FIGS. 3-6 , seal member 118 includes a fabric disc-shaped portion 128 which is preferably disposed on both the proximal and distal sides of inner section 118 b of seal member 118 . Alternatively, fabric section 128 may be disposed on just one of either the proximally facing surface or the distally facing surface of inner portion 118 b , as desired. Fabric portion 128 may be of any suitable fabric, for example, a SPANDEX material containing 20% LYCRA available from Milliken. [0041] In one method of forming the composite seal member 118 with fabric portion 128 a raw, i.e., uncured polyisoprene plug is first compressed into a flat state, e.g., a flat sheet of polyisoprene. A single layer of fabric is positioned on top of the flattened polyisoprene sheet and compressed into the uncured rubber by any suitable compression process such as, for example, calendering. If it is desired to have fabric on both sides of seal member 118 , this process is repeated on the other side of the polyisoprene sheet. The fabric polyisoprene composite is die cut into circular slugs having an outer diameter and an inner diameter which forms a central aperture. The slugs are placed in a hot compression mold to cure the polyisoprene. This step also serves to extrude the outer portions of seal member 118 which extend outwardly from inner section 118 b. [0042] During the above-described process the bleed-through of the polyisoprene material into and/or through the fabric layers is regulated by the density of the fabric selected. A greater degree of bleed-through of polyisoprene provides greater resistance to fraying of the fabric upon repeated insertion of instruments through the seal. However, too much bleed-through of the polyisoprene through the fabric will increase friction forces upon instruments being inserted through seal member 118 . [0043] Referring to FIG. 6A , an alternative embodiment of seal member 118 is shown as seal member 418 . Seal member 418 is the same as seal member 118 in most aspects except that inner section 418 b is formed to have fabric layer 428 enveloped between upper and lower polyisoprene layers 418 c and 418 d. [0044] In order to reduce friction between instruments and the seal member, e.g. seal member 118 or seal member 418 , as instruments are inserted through seal assembly 100 , a coating may be applied to the seal member. One coating which has been found particularly effective is a hydrocyclosiloxane membrane prepared by plasma polymerization process. Such a coating is available from Innerdyne, Inc. of Salt Lake City, Utah, U.S.A., and is disclosed in U.S. Pat. No. 5,463,010 which issued to Hu, et al. on Oct. 31, 1995, the entire contents of which are hereby incorporated by reference. [0045] Referring to FIGS. 7 and 8 , seal assembly 100 is used in combination with a conventional trocar assembly which includes a cannula assembly 110 and a trocar obturator 112 . Examples of trocar assemblies in which the present seal assembly may be utilized are disclosed in U.S. Pat. No. 5,603,702 which issued on Feb. 18, 1997 to Smith et al. and U.S. application Ser. No. 08/546,009 filed Oct. 20, 1995 by Smith et al., the entire contents of each of these disclosures are hereby incorporated by reference. [0046] Seal assembly 100 , either alone or in combination with a seal unit/seal assembly internal to cannula assembly 110 , provides a substantial seal between a body cavity of a patient and the outside atmosphere both during and subsequent to insertion of an instrument through the cannula. In this manner, insufflation gases are prevented from escaping through the trocar assembly to the outside environment. Seal assembly 100 is capable of accommodating instruments of varying diameter, e.g., from about 5 mm to about 12 mm, while providing a fluid tight seal with the outer diameter of each instrument. The versatility of the presently disclosed seal assembly embodiments greatly facilitate endoscopic surgery, wherein a variety of instruments having different diameters are often needed during a single surgical procedure. [0047] Seal assembly 100 is preferably detachably mountable to the proximal end of cannula assembly 110 . Thus, the surgeon can remove the seal assembly 100 from the cannula assembly 110 at any time during the surgical procedure and, similarly, mount the seal assembly 100 to the cannula when desired in order to provide a sealing engagement with an instrument to be inserted through the cannula. In addition, seal assembly 100 may be readily adapted for mounting to conventional cannulas of differing structures. The detachability of seal assembly 100 from cannula assembly 110 facilitates specimen removal through cannula assembly 110 . Seal assembly 100 includes a housing which is formed by the snap fitting together of end cap 114 and lower housing member 116 . Preferably the housing components of seal assembly 100 are formed of a polycarbonate material such as ABS available from the General Electric Company. [0048] FIG. 9 shows an instrument having a shaft 130 inserted through seal assembly 100 and a duck bill valve or “zero” seal valve 132 which prevents the escape of insufflation gases in the absence of an instrument in the trocar assembly. As shown in FIG. 9 , seal member 118 provides a seal about the periphery of shaft 130 . [0049] Referring to FIG. 10 , an alternate embodiment of seal assembly 100 is designated generally as seal assembly 150 . Seal assembly 150 is the same as seal assembly 100 except that an inner planar seal member 152 is disposed in the distal end of seal assembly 100 to provide additional sealing capability for instruments having larger diameters. Seal element 152 has an aperture 154 which has a diameter larger than the diameter of aperture 156 of seal member 118 . A further feature illustrated in FIG. 10 is a dampening member such as pad 158 which is secured to the proximal surface of ring 122 to dampen the sound created by the impact of the proximal surface of ring 122 with the inner distal facing surface of housing component 114 . Other dampening member configurations are also contemplated. For example, ring 122 may be over-molded with material such as polyisoprene so as to envelope part or all of the ring thereby forming a bumper between the ring and the housing component. [0050] Referring to FIGS. 11-13 , a further embodiment of a seal assembly generally designated as seal assembly 200 is shown throughout the several views. Seal member 218 is configured in an hourglass shape and preferably includes the fabric portion 228 formed as part of seal member 218 in a similar manner as described above. The friction reducing coating of a hydrocyclosiloxane membrane prepared by plasma polymerization process noted above may also be utilized to coat the surfaces of seal member 218 . [0051] Referring now to FIGS. 14 and 15 , a further embodiment of the seal assembly generally designated as seal assembly 300 is shown. Seal member 318 is similar to seal member 118 except that inner portion 318 b is formed in a conical shape with a wider opening directed towards a proximal end of seal assembly 300 and a narrower opening directed towards distal end of seal assembly 300 . The friction reducing coating of a hydrocyclosiloxane membrane prepared by plasma polymerization process noted above may also be utilized to coat the surfaces of seal member 318 . [0052] It will be understood that various modifications may be made to the embodiments shown herein. Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the presently disclosed seal assemblies.
A seal assembly for reception of an elongated surgical instrument is provided which includes a body having at least one opening configured and dimensioned to permit entry of an elongated surgical instrument and defining a central longitudinal axis; a seal member formed of a resilient material and defining an aperture therein, the aperture being configured and dimensioned such that insertion of the surgical instrument into the aperture causes the resilient material defining the aperture to resiliently contact the outer surface of the surgical instrument in a substantially fluid tight manner; and a fabric layer juxtaposed relative to the resilient material. A coating may be applied to the seal member to reduce friction between the seal member and surgical instrumentation inserted therein. The coating is preferably a hydrocyclosiloxane membrane prepared by plasma polymerization process.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation application of co-pending U.S. Ser.", "No. 12/546,968, filed Aug. 25, 2009, which is a continuation application of U.S. patent application Ser.", "No. 10/718,195, filed Nov. 20, 2003, which is a continuation application of U.S. patent application Ser.", "No. 10/670,032, filed Sep. 24, 2003, now abandoned, which is a continuation application of U.S. patent application Ser.", "No. 10/165,373, filed Jun. 6, 2002, now U.S. Pat. No. 6,702,787, which is a continuation application of U.S. patent application Ser.", "No. 09/527,955, filed Mar. 9, 2000, now abandoned, which is a continuation application of International Patent Application No. PCT/US98/08968, filed May 1, 1998, which claims priority from U.S. Provisional Patent Application No. 60/045,412, filed May 2, 1997, now expired.", "BACKGROUND [0002] 1.", "Technical Field [0003] The present disclosure relates to seal systems of the type adapted to allow the introduction of a surgical instrument into a patient's body.", "In particular, the disclosure relates to a seal system to be used in combination with a cannula assembly where the cannula assembly is intended for insertion into a patient's body and an instrument is inserted into the patient's body through the cannula.", "[0004] 2.", "Background of the Related Art [0005] Laparoscopic procedures are performed in the interior of the abdomen through a small incision, e.g., through narrow endoscopic tubes or cannulas inserted through a small entrance incision in the skin.", "Minimally invasive procedures are performed elsewhere in the body, e.g., in the chest, and are often generally referred to as “endoscopic”", "procedures.", "Minimally invasive or endoscopic procedures generally require that any instrumentation inserted into the body be sealed, i.e. provisions must be made to ensure that gases do not enter or exit the body through the endoscopic incision as, for example, in surgical procedures in which the surgical region is insufflated.", "Moreover, endoscopic procedures often require the surgeon to act on organs, tissues, and vessels far removed from the incision, thereby requiring that any instruments used in such procedures be relatively long and narrow.", "[0006] For such procedures, the introduction of a tube into certain anatomical cavities such as the abdominal cavity is usually accomplished by use of a system incorporating a trocar and cannula assembly.", "A cannula assembly is formed of a cannula attached to a cannula housing which generally includes seal assembly adapted to maintain a seal across the opening of the seal assembly both with and without an instrument inserted therethrough.", "Since the cannula is in direct communication with the internal portion of the seal assembly, insertion of the cannula into an opening in the patient's body so as to reach the inner abdominal cavity should be adapted to maintain a fluid tight interface between the abdominal cavity and the outside atmosphere.", "[0007] Since minimally invasive surgical procedures in the abdominal cavity of the body generally require insufflating gases to raise the cavity wall away from vital organs, the procedure is usually initiated by use of a Verres needle through which a gas is introduced into the body cavity.", "The gas provides a slight pressure which raises the wall surface of the peritoneum away from the vital organs thereby providing an adequate region in which to operate.", "Thereafter, a trocar assembly which includes a cannula and a trocar or obturator is inserted within the cannula to puncture the peritoneum, i.e. the inner lining of the abdominal cavity wall.", "The obturator is removed and laparoscopic or endoscopic surgical instruments may then be inserted through the cannula to perform surgery within the abdominal cavity.", "The cannula may also be utilized for introducing tubes into the body as for drainage purposes, for specimen removal, for diagnostic evaluations, or the like.", "[0008] In view of the need to maintain the atmospheric integrity of the inner area of the cavity, a seal assembly for a cannula which permits introduction of an obturator and a wide range of surgical instruments and which maintains the atmospheric integrity of the inner area of the cavity is desirable.", "Generally, in the context of insufflatory, minimally invasive surgical procedures, cannula assemblies include structure(s) that satisfy two sealing requirements.", "The first requirement is to provide a substantially fluid tight seal when an instrument is not present in the cannula.", "The second requirement is to provide a substantially fluid tight seal when an instrument is being introduced into or already is present in the cannula.", "In this regard, there have been a number of attempts in the prior art to provide such sealing requirements.", "[0009] U.S. Pat. No. 4,655,752 to Honkanen, et al.", "teaches a cannula including a housing and first and second seal members.", "The first seal member is conically tapered toward the bottom of the housing and has a circular opening in its center, while the second seal is conically tapered and cup shaped.", "The second seal includes at least one slit to allow for the passage of instruments.", "[0010] U.S. Pat. No. 4,929,235 to Merry, et al.", "teaches a self-sealing catheter introducer having a sealing mechanism to prevent blood or fluid leakage.", "The sealing mechanism includes a planar sealing element having a slit and a conical sealing element.", "The sealing elements are each adapted to surround a tube.", "[0011] U.S. Pat. Nos. 4,874,377 and 5,064,416 to Newgard, et al.", "relate to a self-occluding intravascular cannula assembly in which an elastomeric valving member is positioned transversely to a housing and is peripherally compressed to cause displacement, distortion and/or rheological flow of the elastomeric material.", "A frustoconical dilator projection cooperates with the elastomeric valving member in moving the valving member to a non-occluding position.", "[0012] U.S. Pat. No. 5,300,033 to Miller suggests a valve construction including an elastic body having a cylindrical wall with first and second walls formed integrally with the cylindrical wall.", "The second wall includes a slit to permit passage of a surgical instrument and first and second leaflets which define the slit.", "The leaflets are thicker in cross section to provide an additional closing force at the slit.", "[0013] A disadvantage of several known seal systems for cannulas concerns the difficulty encountered in inserting and advancing the surgical instrument through the seal unit.", "In particular, since known elastomeric seal members are designed to form and maintain a fluid tight seal about the instrument, the aperture or slit within the seal through which the instrument is passed is of relatively small or narrow dimension.", "Further, portions of the seal member defining the aperture are generally thick in cross-section to provide a sufficient closing force of the seal about the instrument.", "See, e.g., U.S. Pat. No. 5,300,033.", "As a consequence of these design considerations, the level of force needed to insert and advance the instrument through the seal aperture is increased, thereby requiring awkward maneuvering on the surgeon's behalf to appropriately position the instrument for the desired surgery.", "Moreover, known seal systems are generally ineffectual in accommodating instruments of differing diameter while maintaining acceptable insertion forces and facilitating the range of desired surgical manipulations, e.g., angular instrument movements and specimen removal.", "[0014] Accordingly, the present disclosure obviates the disadvantages of the prior art by providing a seal unit or assembly for a cannula assembly, which is capable of forming and maintaining a tight seal about instruments of varying diameters inserted through the cannula and which incorporates structure to enhance and facilitate passage of the instrument through the seal unit.", "SUMMARY [0015] The present disclosure provides a seal assembly for reception of an elongated surgical instrument, which comprises a body having at least one opening configured and dimensioned to permit entry of an elongated surgical instrument and defining a central longitudinal axis;", "a seal member formed of a resilient material and defining an aperture therein, the aperture being configured and dimensioned such that insertion of the surgical instrument into the aperture causes the resilient material defining the aperture to resiliently contact the outer surface of the surgical instrument in a substantially fluid tight manner;", "and a fabric layer juxtaposed relative to the resilient material.", "[0016] The seal assembly may further include a coating applied to the seal member to reduce friction between the seal member and surgical instrumentation inserted therein.", "The coating is preferably a hydrocyclosiloxane membrane prepared by plasma polymerization process.", "[0017] In one aspect of the presently disclosed seal assembly a ring member is secured to the seal member and includes a dampening element disposed between a surface of the ring member and a surface of the body.", "BRIEF DESCRIPTION OF THE DRAWINGS [0018] Various embodiments are described herein below with reference to the drawings wherein: [0019] FIG. 1 is a perspective view of one embodiment of a seal assembly constructed in accordance with the present disclosure;", "[0020] FIG. 2 is a perspective view with parts separated showing the various structural components of the seal assembly embodiment of FIG. 1 ;", "[0021] FIG. 3 is a perspective view of a fabric portion for incorporation into the seal element of the embodiment of FIG. 1 ;", "[0022] FIG. 4 is a cross-sectional view taken along section line 4 - 4 of FIG. 3 ;", "[0023] FIG. 5 is a perspective view of a fully formed seal member for the seal assembly of FIG. 1 ;", "[0024] FIG. 6 is a cross-sectional view taken along section line 6 - 6 of FIG. 5 ;", "[0025] FIG. 6A is an alternative embodiment of the seal element of FIG. 6 ;", "[0026] FIG. 7 is a cross-sectional view of the seal assembly of FIG. 1 ;", "[0027] FIG. 8 is a perspective view of a trocar assembly having the seal assembly of FIG. 1 removably installed thereon;", "[0028] FIG. 9 is a partial cross-sectional view showing the seal body housing taken along section line 9 - 9 of FIG. 8 ;", "[0029] FIG. 10 is an alternative embodiment of the seal assembly of the present disclosure;", "[0030] FIG. 11 is a cross-sectional view of a further embodiment of the seal assembly constructed in accordance with the present disclosure;", "[0031] FIG. 12 is a perspective view of the seal assembly of FIG. 11 ;", "[0032] FIG. 13 is a perspective view with parts separated of the seal assembly embodiment of FIG. 11 ;", "[0033] FIG. 14 is a cross-sectional view of a further embodiment of the seal assembly constructed in accordance with the present disclosure;", "and [0034] FIG. 15 is a perspective view of the seal member of the seal assembly of FIG. 14 .", "DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS [0035] Referring now in detail to the drawing figures in which like reference numerals identify similar or identical elements, a first embodiment of the seal assembly of the present disclosure is illustrated in FIGS. 1-9 , and is designated generally as seal assembly 100 .", "[0036] The presently disclosed seal assembly embodiments contemplate the introduction of various types of surgical instruments adapted for insertion through an elongated trocar assembly.", "Examples of such instruments include clip appliers, graspers, dissectors, retractors, staplers, laser fibers, photographic devices, endoscopes and laparoscopes, tubes, and the like.", "Such instruments are collectively referred to herein as “instruments.”", "[0037] Referring to FIG. 2 , seal assembly 100 includes a seal member 118 disposed within the seal assembly body or housing components 114 and 116 which snap fit together by way of flexible tab portions 114 a being deflected upon insertion into receiving openings (not shown) formed in housing component 116 .", "Seal member 118 has a circular array of holes formed therethrough around the periphery of an inner section 118 b. [0038] A two part ring assembly which includes ring members 120 and 122 are snap fitted together on either side of seal member 118 .", "Ring member 120 is disposed adjacent the distally facing surface of seal member 118 and ring member 122 is disposed on the proximally facing side of seal member 118 .", "Ring 120 is provided with holes 120 a and posts 120 b which are alternately disposed around the ring and are aligned with holes 118 a on seal member 118 .", "Ring 122 is provided with posts 122 a and holes 122 b which mate with holes 120 a and posts 120 b of ring member 120 , respectively by snap fitting together thereby surrounding inner section 118 b .", "Although rings 120 and 122 are shown having alternating holes and posts, one of the rings could have all holes formed therein while the other ring could have all posts aligned with the holes of the other ring.", "Additionally, greater or fewer holes and posts may be utilized to secure the two rings together.", "[0039] A seal clamp 124 is provided within the housing component 114 and 116 and serves to secure the outer periphery of seal member 118 within seal assembly 100 (as best shown in FIG. 7 ).", "Seal clamp 124 is provided with four projecting posts 124 a which fit within openings ( FIG. 7 ) formed on the proximal side of lower housing 116 .", "Seal clamp 124 also serves to secure a proximal flange of a lower seal 126 which is provided at the distal end of lower housing member 116 .", "Lower seal 126 assists in the securement of seal assembly 100 to cannula assembly 110 .", "[0040] Referring now to FIGS. 3-6 , seal member 118 includes a fabric disc-shaped portion 128 which is preferably disposed on both the proximal and distal sides of inner section 118 b of seal member 118 .", "Alternatively, fabric section 128 may be disposed on just one of either the proximally facing surface or the distally facing surface of inner portion 118 b , as desired.", "Fabric portion 128 may be of any suitable fabric, for example, a SPANDEX material containing 20% LYCRA available from Milliken.", "[0041] In one method of forming the composite seal member 118 with fabric portion 128 a raw, i.e., uncured polyisoprene plug is first compressed into a flat state, e.g., a flat sheet of polyisoprene.", "A single layer of fabric is positioned on top of the flattened polyisoprene sheet and compressed into the uncured rubber by any suitable compression process such as, for example, calendering.", "If it is desired to have fabric on both sides of seal member 118 , this process is repeated on the other side of the polyisoprene sheet.", "The fabric polyisoprene composite is die cut into circular slugs having an outer diameter and an inner diameter which forms a central aperture.", "The slugs are placed in a hot compression mold to cure the polyisoprene.", "This step also serves to extrude the outer portions of seal member 118 which extend outwardly from inner section 118 b. [0042] During the above-described process the bleed-through of the polyisoprene material into and/or through the fabric layers is regulated by the density of the fabric selected.", "A greater degree of bleed-through of polyisoprene provides greater resistance to fraying of the fabric upon repeated insertion of instruments through the seal.", "However, too much bleed-through of the polyisoprene through the fabric will increase friction forces upon instruments being inserted through seal member 118 .", "[0043] Referring to FIG. 6A , an alternative embodiment of seal member 118 is shown as seal member 418 .", "Seal member 418 is the same as seal member 118 in most aspects except that inner section 418 b is formed to have fabric layer 428 enveloped between upper and lower polyisoprene layers 418 c and 418 d. [0044] In order to reduce friction between instruments and the seal member, e.g. seal member 118 or seal member 418 , as instruments are inserted through seal assembly 100 , a coating may be applied to the seal member.", "One coating which has been found particularly effective is a hydrocyclosiloxane membrane prepared by plasma polymerization process.", "Such a coating is available from Innerdyne, Inc. of Salt Lake City, Utah, U.S.A., and is disclosed in U.S. Pat. No. 5,463,010 which issued to Hu, et al.", "on Oct. 31, 1995, the entire contents of which are hereby incorporated by reference.", "[0045] Referring to FIGS. 7 and 8 , seal assembly 100 is used in combination with a conventional trocar assembly which includes a cannula assembly 110 and a trocar obturator 112 .", "Examples of trocar assemblies in which the present seal assembly may be utilized are disclosed in U.S. Pat. No. 5,603,702 which issued on Feb. 18, 1997 to Smith et al.", "and U.S. application Ser.", "No. 08/546,009 filed Oct. 20, 1995 by Smith et al.", ", the entire contents of each of these disclosures are hereby incorporated by reference.", "[0046] Seal assembly 100 , either alone or in combination with a seal unit/seal assembly internal to cannula assembly 110 , provides a substantial seal between a body cavity of a patient and the outside atmosphere both during and subsequent to insertion of an instrument through the cannula.", "In this manner, insufflation gases are prevented from escaping through the trocar assembly to the outside environment.", "Seal assembly 100 is capable of accommodating instruments of varying diameter, e.g., from about 5 mm to about 12 mm, while providing a fluid tight seal with the outer diameter of each instrument.", "The versatility of the presently disclosed seal assembly embodiments greatly facilitate endoscopic surgery, wherein a variety of instruments having different diameters are often needed during a single surgical procedure.", "[0047] Seal assembly 100 is preferably detachably mountable to the proximal end of cannula assembly 110 .", "Thus, the surgeon can remove the seal assembly 100 from the cannula assembly 110 at any time during the surgical procedure and, similarly, mount the seal assembly 100 to the cannula when desired in order to provide a sealing engagement with an instrument to be inserted through the cannula.", "In addition, seal assembly 100 may be readily adapted for mounting to conventional cannulas of differing structures.", "The detachability of seal assembly 100 from cannula assembly 110 facilitates specimen removal through cannula assembly 110 .", "Seal assembly 100 includes a housing which is formed by the snap fitting together of end cap 114 and lower housing member 116 .", "Preferably the housing components of seal assembly 100 are formed of a polycarbonate material such as ABS available from the General Electric Company.", "[0048] FIG. 9 shows an instrument having a shaft 130 inserted through seal assembly 100 and a duck bill valve or “zero”", "seal valve 132 which prevents the escape of insufflation gases in the absence of an instrument in the trocar assembly.", "As shown in FIG. 9 , seal member 118 provides a seal about the periphery of shaft 130 .", "[0049] Referring to FIG. 10 , an alternate embodiment of seal assembly 100 is designated generally as seal assembly 150 .", "Seal assembly 150 is the same as seal assembly 100 except that an inner planar seal member 152 is disposed in the distal end of seal assembly 100 to provide additional sealing capability for instruments having larger diameters.", "Seal element 152 has an aperture 154 which has a diameter larger than the diameter of aperture 156 of seal member 118 .", "A further feature illustrated in FIG. 10 is a dampening member such as pad 158 which is secured to the proximal surface of ring 122 to dampen the sound created by the impact of the proximal surface of ring 122 with the inner distal facing surface of housing component 114 .", "Other dampening member configurations are also contemplated.", "For example, ring 122 may be over-molded with material such as polyisoprene so as to envelope part or all of the ring thereby forming a bumper between the ring and the housing component.", "[0050] Referring to FIGS. 11-13 , a further embodiment of a seal assembly generally designated as seal assembly 200 is shown throughout the several views.", "Seal member 218 is configured in an hourglass shape and preferably includes the fabric portion 228 formed as part of seal member 218 in a similar manner as described above.", "The friction reducing coating of a hydrocyclosiloxane membrane prepared by plasma polymerization process noted above may also be utilized to coat the surfaces of seal member 218 .", "[0051] Referring now to FIGS. 14 and 15 , a further embodiment of the seal assembly generally designated as seal assembly 300 is shown.", "Seal member 318 is similar to seal member 118 except that inner portion 318 b is formed in a conical shape with a wider opening directed towards a proximal end of seal assembly 300 and a narrower opening directed towards distal end of seal assembly 300 .", "The friction reducing coating of a hydrocyclosiloxane membrane prepared by plasma polymerization process noted above may also be utilized to coat the surfaces of seal member 318 .", "[0052] It will be understood that various modifications may be made to the embodiments shown herein.", "Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments.", "Those skilled in the art will envision other modifications within the scope and spirit of the presently disclosed seal assemblies." ]
FIELD OF THE INVENTION The present invention relates to an improved roll-on applicator particularly for applying a lip covering material. The present invention also has particular applicability where a second lip material is being applied over a first lip covering material. The roll-on applicator according to the present invention prevents the color of the lip covering material from appearing on the roller ball of the roll on applicator. BACKGROUND OF THE INVENTION Roll-on applicators are well known in the art. Usually, these applicators are containers comprising a hollow body for liquids or semi liquids, a ball and a retaining support means for said ball. These roll-on applicators generally allow a person to apply a liquid or semi liquid material from the inside of the hollow body to a selected surface. In many applications the material applied is colored or tinted. When this colored material is applied by the roll-on applicator some of the material being applied remains on the ball's outer surface giving the impression to the user that the applicator is soiled. This problem is particularly acute where a second material is being applied over a first material such as where a clear or relatively clear lip gloss is being applied over a colored lip covering. In such situations, portions of the first lip covering material has a tendency to transfer to the surface of the roll-on applicator It is an object of the present invention to provide a container with a roll-on applicating means which prevents the appearance of soiling on the roll-on applicator ball from colored product being dispensed by the applicator. It is also an object of the present invention to provide a roll-on applicator that prevents a first colored lip covering presently on the lips from discoloring the roll-on applicator ball of another cosmetic product. SUMMARY OF THE INVENTION The present invention is directed to an improved application means for applying lip coverings such as lip gloss, various moisturizers, salves, balms, unguents, emoluments and other treatments. The present application has particular application to applying these various materials to lips by means of a roll-on applicator. In particular the invention is advantageous in applications where the wearers already have a lipstick or other lip coloring material present. For example, although many consumers apply lipstick or other colorants to the lips, from time to time there is a need to enhance the look that a traditional lip covering provides. There is available on the market a variety of lip glosses that are applied over a pre-existing lip color. These lip glosses enhance the look of the lips by providing the lips with a high sheen or gloss. Many people believe that the beauty of the lips is enhanced when the lips are perceived as being moistened. Lip glosses provide the lips with this moistened look. Lip glosses can be in the form of a stick which would be applied by an applicator in the same manner as traditional lipsticks are. Another means of applying a lip gloss is from a receptacle by the wearer's fingertips or by a brush. In addition, there are a number of other different types of applicators designed for this product. One common type applicator that is currently available on the market is a container that comprised a reservoir for the lip gloss. The container can be any number of shapes and has an orifice for dispensing the product. Covering the orifice is a rotating ball for applying the lip product particularly a lip gloss to the wearer's lips. As the ball rotates, the lip material is applied to the outer surface of the ball whereby the material is transferred from the interior of the container to the outer by he rotating ball. Other types of containers typically include a brush or an applicator surface that provides a means for retaining the material to be applied as it is being transferred from the container to the lips. One of the problems in applying lip glosses and other products over a pre existing lip stick or other applied color is the problem of transferral, whereby some of the colored material that is currently on the lips transfers to the applicator surface creating an unsightly residue. This unsightly residue creates the impression that the applicator surface is soiled. In addition, if the wearer uses different shades of the same general color there can be multicolored streaks on the applicator surface. This problem is particularly acute in the present rotating ball type applicators which are a white or clear plastic or glass ball. The problem of transferral of lip color from the lips to the rotating ball of the applicator is solved by the present invention whereby the rotating ball is not the traditional clear or white glass or plastic ball. Rather, in the present invention the ball is selected from a color preferably a color of the material being applied where there is no lip covering presently on the lips. Alternatively, where there is a lip coloring already present on the lips, the color of the ball is selected from one that is related to the color of the lip coloring that is presently on the lips. Although it is preferable that the ball be the same color as the lip material being dispensed or already on the lips, it has been found that the ball color can be within a range of color and still mask the coloring of the lip covering material Many consumers have a particular range of lip colors that they use on a regular basis. Depending on the complexion, eye color and the color of the attire being worn the consumer makes a color selection for her lips. While lip colors may change from time to time it is not unusual for the colors to be similar i.e., in the same general family. When a lip gloss or other lip product is purchased to apply to the lips the consumer can select an applicator ball that is similar to the color of the lip stick of the user. The use of the colored ball masks the transferral of the lip product that is currently on the lips to the ball surface. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an example of a roll-on applicator or container for applying lip covering material such as lip stick, lip gloss or other products. FIG. 2 shows another type of roll-on applicator for applying lip covering material. FIG. 3 shows an enlarged view of a roller ball in a roll on applicator where the ball is forced into position against the applicator orifice by a spring. FIG. 4 shows the roller ball of FIG. 3 where a force F has been applied to the outer surface of the roller ball forcing the ball away from the applicator orifice to permit application of product from the interior of the applicator to the consumer. FIG. 5 shows an insert that contains the roller ball which may be inserted into the opened end of the applicator. FIG. 6 shows an applicator with the insert in place. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows an example of the type of containers for use with the present invention. The container may be of any shape or size. FIG. 1 is a generic container 10 having a base 11 , a front surface 12 , a rear surface 13 , a pair of sidewalls 14 and 15 and an orifice 16 at the top. The walls of a container may taper to form a breast 17 and a neck 18 . The ball 19 is rotatably mounted in the container by any suitable means and may be retained in place by a tip 20 of the applicator or a separate insert. When the container is tilted toward the lips of the user, the product 21 within the container contacts the ball surface 22 on the interior of the container. When the ball is rotated the product passes between the ball surface and the collar and is available for application to the user on the surface 23 of the ball outside the container. When the ball is made of a glass or plastic material, the ball can be any chromatic or nonchromatic color. Chromatic colors are the colors of the visible spectrum. Nonchromatic colors include the browns, magentas and pinks. Excluded from the present invention are the achromatic colors of the white-light gray sequence. For purposes of this application the color white may also include clear without any pigment or color. When the ball is comprised of a metallic material on at least its exterior surface the ball may be any chromatic or nonchromatic color except a silver or gold. Black is a color that is included within the invention as it will mask virtually any color. The term color is the perceptual result of light incident upon the retina, in the visible region of the spectrum having wavelengths in the range of about 350 mn to about 750 mn although the more typical range is 400 nm to 700 nm. The Table below shows the typical range of the visible spectrum: Wavelength Frequency Energy Color (nm) (100,000,000,000,000 Hz) (EV) Red (limit) 700 4.29 1.77 Red 650 4.62 1.91 Orange 600 5.00 2.06 Yellow 580 5.16 2.14 Green 550 5.45 2.25 Cyan 500 5.99 2.48 Blue 450 6.66 2.75 Violet (limit) 400 7.50 3.10 The color of the ball of the present invention may be measured by either the absorption of light by the surface of the ball or by the reflection of light off its surface. For example, in one theory concerning color, a substance that appears yellow does so because it absorbs most strongly in the blue part of the spectrum and scatters most strongly in the red and green parts of the spectrum. It is also not unusual for a pigment to scatter light most efficiently in one region of the spectrum while having its main absorption band in another. Putting it a different way, if light having a wavelength of about 550 nm is reflected off of the surface of the ball the color of the ball to the eye is green. Alternatively, if light in the range of about 400-549 nm and about 551-700 nm is absorbed by the surface of the ball the ball will also appear green. Bear in mind that the spectrum of light is continuous and does not have defined breaks for the colors. The wavelengths set out above are commonly ascribed to the particular colors but it will be recognized by those skilled in the art that one persons perception of color may differ from another's. Accordingly, what one person perceives as for example blue may not have the same exact wave length as the blue perceived by someone else. However, the blues seen by each party should be in generally the same region of the spectrum. Typically, a consumer applies a lip covering material such as lipstick to her lips. This may be applied by any suitable fashion such as by a traditional lipstick, a brush, by her finger tips or some other means. At some point, perhaps immediately thereafter or later in the day, she may decide to apply a lip gloss, a moisturizer, salve, balm, unguent, emolument or other treatment to her lips over the initial lipstick. The lip covering material originally present on the lips is a material that reflects light at a wavelength in the range of about 350 to about 750 nm. In accordance with the present invention the applicator will have a rotating ball to apply the lip gloss or topical lip treatment to the consumer. The ball of the present invention will be a colored ball preferably comprised of a glass or plastic material although any suitable material including metal may be used. The roll-on ball of the dispenser of the present invention will not become discolored or cause transferral of the original lip material to the ball in the dispenser if the ball on the dispenser of the present invention reflects light in the range of 350 to about 750 nm. More preferably, when the lip covering material reflects light at a wavelength in the range of about 400 to about 700 nm, the roll-on ball of the dispenser of the present invention will not be seen on the ball and/or will not cause transferral of the original lip material on the lips to the ball if the ball on the dispenser of the present invention reflects light in the range of 400 to about 700 nm. When the first lip material is a nonchromatic color the ball of the dispenser is preferably also a nonchromatic color. More preferably, where the nonchromatic color is a brown, the ball of the dispenser of the present invention should also be a brown. Where the nonchromatic color is a pink, the ball of the dispenser of the present invention should also preferably be a pink. Where the nonchromatic color is a magenta the ball of the dispenser of the present invention should also preferably be a magenta. Where there is no lip material on the lips presently preferably the roll-on ball should be the color of the lip covering material in the dispenser. In a preferred embodiment of the present invention for chromatic colors, the color of the ball should be in generally the same region of the spectrum as the color of the first lip material that was applied to the lips prior to the application of the lip gloss or other topical lip treatment. When this occurs any transferral of the original lip material is masked by the color of the ball. This is demonstrated by the following prophetic examples: EXAMPLE 1 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 600 to about 700 nm. If the color of the ball on an applicator is selected so that it also reflects light at a wave length in the range of about 600 to about 700 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 2 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 600 to about 700 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 600 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 3 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 580 to about 650 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 580 nm to about 650 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 4 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 580 to 650 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 580 nm and 650 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 5 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 550 to 600 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 550 nm to about 600 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 6 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 550 to 600 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 550 nm and 600 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 7 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 500 to 580 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 500 nm to about 580 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 8 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 500 to 580 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 500 nm and 580 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 9 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 450 to 550 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 450 nm to about 550 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 10 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 450 to 550 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 450 nm and 550 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 11 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 400 to 500 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 400 nm to about 500 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 12 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 400 to 500 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 500 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 13 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 650 to about 700 nm. If the color of the ball on an applicator is selected so that it also reflects light at a wave length in the range of about 650 to about 700 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 14 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 650 to about 700 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 650 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 15 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 600 to about 650 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 600 nm to about 650 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 16 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 600 to 650 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 600 nm and 650 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 17 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 500 to 600 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 500 nm to about 600 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 18 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 500 to 600 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 500 nm and 600 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 19 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 500 to 550 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 500 nm to about 550 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 20 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 500 to 550 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 500 nm and 550 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 21 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 450 to 500 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 450 nm to about 500 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 22 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 450 to 500 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 450 nm and 500 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 23 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 400 to 450 nm. If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 400 nm to about 450 nm any transferal of the original lipstick material will be masked by the color of the ball. EXAMPLE 24 A lipstick is applied to the lips of a consumer. This lipstick has a color that reflects light at a wave length of about 400 to 450 nm. If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 450 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball. In addition to characterizing a color by its wavelength, the color of the ball may also be characterized, in many instances, by its Pantone Number. In the present invention depending on the color of the lip covering material, the ball color may include but is not limited to any one of the following Pantone colors or combinations thereof: Yellow C Yellow 012 C Orange 021 C Warm Red C Red 032 C Rubine Red C Rhodamine Red C Purple C Violet C Blue 072 Reflex Blue Process Blue C Green C Process yellow C Process Black C Process Magenta C Process Cyan C Hexachrome Yellow C Hexachrome Orange C Hexachrome Magenta C Hexachrome Cyan C Haxachrome Black C Hexachrome Green C Pantone 100 C to 399 C, 429C to 433C, 430C to 433C, 437 C -440 C, 441 C to 587 C, 600 C-732 C, 801 C-814 C, Pantonel1205 C, 1215 C, 1225 C, 1235 C, 1245 C, 1255 C, 1265 C, Pantone 1345 C, 1355 C, 1365 C, 1375 C, 1385 C, 1395 C, 1405 C Pantone 1485 C, 1495 C, 1505 C, 1525 C, 1535 C, 1545 C, 1555 C, 1565 C, 1575 C, 1585 C, 1595 C, 1605 C, 1615 C, 1625 C, 1635 C, 1645 C, 1655 C, 1665 C, 1675 C, 1685 C, 1765 C, 1775 C, 1785 C, 1795 C, 1805 C, 1815 C, 1767 C, 1777 C, 1787 C, 1797 C, 1807 C, 1817 C, 1895 C, 1905 C, 1915 C, 1925 C, 1935 C, 1945 C, 1955 C, 2365 C, 2375 C, 2385 C, 2395 C, 2405 C, 2415 C, 2425 C, 2562 C, 2572 C, 2582 C, 2592 C, 2602 C, 2612 C, 2622 C, 2563 C, 2573 C, 2583 C, 2593 C, 2603 C, 2613 C, 2623 C, 2567 C, 2577 C, 2587 C, 2597 C, 2607 C, 2617 C, 2627 C, 2635 C 2645 C, 2655 C, 2675 C, 2685 C, 2695 C, 2705 C, 2715 C, 2725 C, 2735 C, 2745 C, 2755 C, 2765 C, 2706 C, 2716 C, 2726 C, 2736 C, 2746 C, 2756 C, 2766 C, 2707 C, 2717 C, 2727 C, 2737 C, 2747 C, 2757 C, 2767 C, 2708 C, 2718 C, 2728 C, 2738 C, 2748 C, 2758 C, 2768 C, 2905 C, 2915 C, 2925 C, 2935 C, 2945 C, 2955 C, 2965 C, 2975 C, 2985 C, 2995 C, 3005 C, 3015 C, 3025 C, 3035 C, 3105 C, 3115 C, 3125 C, 3135 C, 3145 C, 3155 C, 3165 C, 3242 C, 3252 C, 3262 C, 3272 C, 3282 C, 3292 C, 3302 C, 3245 C, 3255 C, 3265 C, 3275 C, 3285 C, 3295 C, 3305 C, 3248 C, 3258 C, 3268 C, 3278 C, 3288 C, 3298 C, 3308 C, 3935 C, 3945 C, 3955 C, 3965 C, 3975 C, 3985 C, 3995 C, 4485 C, 4495 C, 4505 C, 4515 C, 4525 C, 4535 C, 4545 C, 4625 C, 4635 C, 4645 C, 4655 C, 4665 C, 4675 C, 4685 C, 4695 C, 4705 C, 4715 C, 4725 C, 4735 C, 4745 C, 4755 C, 4975 C, 4985 C, 4995 C, 5005 C, 5015 C, 5025 C, 5035 C, 5115 C, 5125 C, 5135 C, 5145 C, 5155 C, 5165 C, 5175 C, 5185 C, 5195 C, 5205 C, 5215 C, 5225 C, 5235 C, 5245 C, 5255 C, 5265 C, 5275 C, 5285 C, 5295 C, 5305 C, 5315 C, 5395 C, 5405 C, 5415 C, 5425 C, 5435 C, 5445 C, 5455 C, 5463 C, 5473 C, 5483 C, 5493 C, 5503 C, 5513 C, 5523 C, 5467 C, 5477 C, 5487 C, 5497 C, 5507 C, 5517 C, 5527 C, 5535 C, 5545 C, 5555 C, 5565 C, 5575 C, 5585 C, 5595 C, 5743 C, 5753 C, 5763 C, 5773 C, 5783 C, 5793 C, 5803 C, 5747 C, 5757 C, 5767 C, 5777 C, 5787 C, 5797 C, 5807 C, 5815 C, 5825 C, 5835 C, 5845 C, 5855 C, 5865 C, 5875 C Black 2C, 3C, 4C, 5C, 6C, 7C Warm Gray 5C-11C Yellow U Yellow 012 U Orange 021 U Warm Red U Red 032 U Rubine Red U Rhodamine Red U Purple U Violet U Blue 072 U Reflex Blue U Process Blue U Green U Process yellow U Process Magenta U Process Cyan U Process Black U Hexachrome Yellow U Hexachrome Orange U Hexachrome Magenta U Hexachrome Black U Hexachrome Cyan U Hexachrome Green U Pantone 100 U to 399 U, 429U to 433U, 430U to 433U, 437U to 440 U, 441 U to 587 U, 600 U -732 U, 801 U-814 U, Pantone 1206 U, 1215 U, 1225 U, 1235 U, 1245 U, 1255U, 1265 U, Pantone 1345 U, 1355 U, 1365 U, 1375 U, 1385 U, 1395 U, 1405 U Pantone 1485 U, 1495 U, 1505 U, 1525 U, 1535 U, 1545 U, 1555 U, 1565 U, 1575 U, 1585 U, 1595 U, 1605 U, 1615 U, 1625 U, 1635 U, 1645 U, 1655 U, 1665 U, 1675 U, 1685 U, 1765 U, 1775 U, 1785 U, 1795 U, 1805 U, 1815 U, 1767 U, 1777 U, 1787 U, 1797 U, 1807 U, 1817 U, 1895 U, 1905 U, 1915 U, 1925 U, 1935 U, 1945 U, 1955 U, 2365 U, 2375 U, 2385 U, 2395 U, 2405 U, 2415 U, 2425 U, 2562 U, 2572 U, 2582 U, 2592 U, 2602 U, 2612 U, 2622 U, 2563 U, 2573 U, 2583 U, 2593 U, 2603 U, 2613 U, 2623 U, 2567 U, 2577 U, 2587 U, 2597 U, 2607 U, 2617 U, 2627 U, 2635 U, 2645 U, 2655 U, 2675 U, 2685 U, 2695 U, 2705 U, 2715 U, 2725 U, 2735 U, 2745 U, 2755 U, 2765 U, 2706 U, 2716 U, 2726 U, 2736 U, 2746 U, 2756 U, 2766 U, 2707 U, 2717 U, 2727 U, 2737 U, 2747 U, 2757 U, 2767 U, 2708 U, 2718 U, 2728 U, 2738 U, 2748 U, 2758 U, 2768 U, 2905 U, 2915 U, 2925 U, 2935 U, 2945 U, 2955 U, 2965 U, 2975 U, 2985 U, 2995 U, 3005 U, 3015 U, 3025 U, 3035 U, 3105 U, 3115 U, 3125 U, 3135 U, 3145 U, 3155 U, 3165U, 3242 U, 3252 U, 3262 U, 3272 U, 3282 U, 3292 U, 3302 U, 3245 U, 3255 U, 3265 U, 3275 U, 3285 U, 3295 U, 3305 U, 3248 U, 3258 U, 3268 U, 3278 U, 3288 U, 3298 U, 3308 U, 3935 U, 3945 U, 3955 U, 3965 U, 3975 U, 3985 U, 3995 U, 4485 U, 4495 U, 4505 U, 4515 U, 4525 U, 4535 U, 4545 U, 4625 U, 4635 U, 4645 U, 4655 U, 4665 U, 4675 U, 4685 U, 4695 U, 4705 U, 4715 U, 4725 U, 4735 U, 4745 U, 4755 U, 4975 U, 4985 U, 4995 U, 5005 U, 5015 U, 5025 U, 5035 U, 5115 U, 5125 U, 5135 U, 5145 U, 5155 U, 5165U, 5175 U, 5185 U, 5195 U, 5205 U, 5215 U, 5225 U, 5235 U, 5245 U, 5255 U, 5265 U, 5275 U, 5285 U, 5295 U, 5305 U, 5315 U, 5395 U, 5405 U, 5415 U, 5425 U, 5435 U, 5445 U, 5455 U, 5463 U, 5473 U, 5483 U, 5493 U, 5503 U, 5513 U, 5523 U, 5467 U, 5477 U, 5487 U, 5497 U, 5507 U, 5517 U, 5527 U, 5535 U, 5545 U, 5555 U, 5565 U, 5575 U, 5585 U, 5595 U, 5743 U, 5753 U, 5763 U, 5773 U, 5783 U, 5793 U, 5803 U, 5747 U, 5757 U, 5767 U, 5777 U, 5787 U, 5797 U, 5807 U, 5815 U, 5825 U, 5835 U, 5845 U, 5855 U, 5865 U, 5875 U Black 2U, 3U, 4U, 5U, 6U, 7U, and Warm Gray 5U-11U.
A container for applying a lip treatment material to a user is described. The lip treatment material may have a chromatic or nonchromatic color or be a dark gray. The container has a base, an outer surface, an inner surface and a top surface. The top surface has at least one orifice therein. The container has a rotatable ball mounted at the orifice for applying the lip treatment material from the container to the lips of the user. The rotatable ball has a color selected from the group consisting of chromatic and nonchromatic colors, blacks or dark grays.
Identify and summarize the most critical technical features from the given patent document.
[ "FIELD OF THE INVENTION The present invention relates to an improved roll-on applicator particularly for applying a lip covering material.", "The present invention also has particular applicability where a second lip material is being applied over a first lip covering material.", "The roll-on applicator according to the present invention prevents the color of the lip covering material from appearing on the roller ball of the roll on applicator.", "BACKGROUND OF THE INVENTION Roll-on applicators are well known in the art.", "Usually, these applicators are containers comprising a hollow body for liquids or semi liquids, a ball and a retaining support means for said ball.", "These roll-on applicators generally allow a person to apply a liquid or semi liquid material from the inside of the hollow body to a selected surface.", "In many applications the material applied is colored or tinted.", "When this colored material is applied by the roll-on applicator some of the material being applied remains on the ball's outer surface giving the impression to the user that the applicator is soiled.", "This problem is particularly acute where a second material is being applied over a first material such as where a clear or relatively clear lip gloss is being applied over a colored lip covering.", "In such situations, portions of the first lip covering material has a tendency to transfer to the surface of the roll-on applicator It is an object of the present invention to provide a container with a roll-on applicating means which prevents the appearance of soiling on the roll-on applicator ball from colored product being dispensed by the applicator.", "It is also an object of the present invention to provide a roll-on applicator that prevents a first colored lip covering presently on the lips from discoloring the roll-on applicator ball of another cosmetic product.", "SUMMARY OF THE INVENTION The present invention is directed to an improved application means for applying lip coverings such as lip gloss, various moisturizers, salves, balms, unguents, emoluments and other treatments.", "The present application has particular application to applying these various materials to lips by means of a roll-on applicator.", "In particular the invention is advantageous in applications where the wearers already have a lipstick or other lip coloring material present.", "For example, although many consumers apply lipstick or other colorants to the lips, from time to time there is a need to enhance the look that a traditional lip covering provides.", "There is available on the market a variety of lip glosses that are applied over a pre-existing lip color.", "These lip glosses enhance the look of the lips by providing the lips with a high sheen or gloss.", "Many people believe that the beauty of the lips is enhanced when the lips are perceived as being moistened.", "Lip glosses provide the lips with this moistened look.", "Lip glosses can be in the form of a stick which would be applied by an applicator in the same manner as traditional lipsticks are.", "Another means of applying a lip gloss is from a receptacle by the wearer's fingertips or by a brush.", "In addition, there are a number of other different types of applicators designed for this product.", "One common type applicator that is currently available on the market is a container that comprised a reservoir for the lip gloss.", "The container can be any number of shapes and has an orifice for dispensing the product.", "Covering the orifice is a rotating ball for applying the lip product particularly a lip gloss to the wearer's lips.", "As the ball rotates, the lip material is applied to the outer surface of the ball whereby the material is transferred from the interior of the container to the outer by he rotating ball.", "Other types of containers typically include a brush or an applicator surface that provides a means for retaining the material to be applied as it is being transferred from the container to the lips.", "One of the problems in applying lip glosses and other products over a pre existing lip stick or other applied color is the problem of transferral, whereby some of the colored material that is currently on the lips transfers to the applicator surface creating an unsightly residue.", "This unsightly residue creates the impression that the applicator surface is soiled.", "In addition, if the wearer uses different shades of the same general color there can be multicolored streaks on the applicator surface.", "This problem is particularly acute in the present rotating ball type applicators which are a white or clear plastic or glass ball.", "The problem of transferral of lip color from the lips to the rotating ball of the applicator is solved by the present invention whereby the rotating ball is not the traditional clear or white glass or plastic ball.", "Rather, in the present invention the ball is selected from a color preferably a color of the material being applied where there is no lip covering presently on the lips.", "Alternatively, where there is a lip coloring already present on the lips, the color of the ball is selected from one that is related to the color of the lip coloring that is presently on the lips.", "Although it is preferable that the ball be the same color as the lip material being dispensed or already on the lips, it has been found that the ball color can be within a range of color and still mask the coloring of the lip covering material Many consumers have a particular range of lip colors that they use on a regular basis.", "Depending on the complexion, eye color and the color of the attire being worn the consumer makes a color selection for her lips.", "While lip colors may change from time to time it is not unusual for the colors to be similar i.e., in the same general family.", "When a lip gloss or other lip product is purchased to apply to the lips the consumer can select an applicator ball that is similar to the color of the lip stick of the user.", "The use of the colored ball masks the transferral of the lip product that is currently on the lips to the ball surface.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an example of a roll-on applicator or container for applying lip covering material such as lip stick, lip gloss or other products.", "FIG. 2 shows another type of roll-on applicator for applying lip covering material.", "FIG. 3 shows an enlarged view of a roller ball in a roll on applicator where the ball is forced into position against the applicator orifice by a spring.", "FIG. 4 shows the roller ball of FIG. 3 where a force F has been applied to the outer surface of the roller ball forcing the ball away from the applicator orifice to permit application of product from the interior of the applicator to the consumer.", "FIG. 5 shows an insert that contains the roller ball which may be inserted into the opened end of the applicator.", "FIG. 6 shows an applicator with the insert in place.", "DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows an example of the type of containers for use with the present invention.", "The container may be of any shape or size.", "FIG. 1 is a generic container 10 having a base 11 , a front surface 12 , a rear surface 13 , a pair of sidewalls 14 and 15 and an orifice 16 at the top.", "The walls of a container may taper to form a breast 17 and a neck 18 .", "The ball 19 is rotatably mounted in the container by any suitable means and may be retained in place by a tip 20 of the applicator or a separate insert.", "When the container is tilted toward the lips of the user, the product 21 within the container contacts the ball surface 22 on the interior of the container.", "When the ball is rotated the product passes between the ball surface and the collar and is available for application to the user on the surface 23 of the ball outside the container.", "When the ball is made of a glass or plastic material, the ball can be any chromatic or nonchromatic color.", "Chromatic colors are the colors of the visible spectrum.", "Nonchromatic colors include the browns, magentas and pinks.", "Excluded from the present invention are the achromatic colors of the white-light gray sequence.", "For purposes of this application the color white may also include clear without any pigment or color.", "When the ball is comprised of a metallic material on at least its exterior surface the ball may be any chromatic or nonchromatic color except a silver or gold.", "Black is a color that is included within the invention as it will mask virtually any color.", "The term color is the perceptual result of light incident upon the retina, in the visible region of the spectrum having wavelengths in the range of about 350 mn to about 750 mn although the more typical range is 400 nm to 700 nm.", "The Table below shows the typical range of the visible spectrum: Wavelength Frequency Energy Color (nm) (100,000,000,000,000 Hz) (EV) Red (limit) 700 4.29 1.77 Red 650 4.62 1.91 Orange 600 5.00 2.06 Yellow 580 5.16 2.14 Green 550 5.45 2.25 Cyan 500 5.99 2.48 Blue 450 6.66 2.75 Violet (limit) 400 7.50 3.10 The color of the ball of the present invention may be measured by either the absorption of light by the surface of the ball or by the reflection of light off its surface.", "For example, in one theory concerning color, a substance that appears yellow does so because it absorbs most strongly in the blue part of the spectrum and scatters most strongly in the red and green parts of the spectrum.", "It is also not unusual for a pigment to scatter light most efficiently in one region of the spectrum while having its main absorption band in another.", "Putting it a different way, if light having a wavelength of about 550 nm is reflected off of the surface of the ball the color of the ball to the eye is green.", "Alternatively, if light in the range of about 400-549 nm and about 551-700 nm is absorbed by the surface of the ball the ball will also appear green.", "Bear in mind that the spectrum of light is continuous and does not have defined breaks for the colors.", "The wavelengths set out above are commonly ascribed to the particular colors but it will be recognized by those skilled in the art that one persons perception of color may differ from another's.", "Accordingly, what one person perceives as for example blue may not have the same exact wave length as the blue perceived by someone else.", "However, the blues seen by each party should be in generally the same region of the spectrum.", "Typically, a consumer applies a lip covering material such as lipstick to her lips.", "This may be applied by any suitable fashion such as by a traditional lipstick, a brush, by her finger tips or some other means.", "At some point, perhaps immediately thereafter or later in the day, she may decide to apply a lip gloss, a moisturizer, salve, balm, unguent, emolument or other treatment to her lips over the initial lipstick.", "The lip covering material originally present on the lips is a material that reflects light at a wavelength in the range of about 350 to about 750 nm.", "In accordance with the present invention the applicator will have a rotating ball to apply the lip gloss or topical lip treatment to the consumer.", "The ball of the present invention will be a colored ball preferably comprised of a glass or plastic material although any suitable material including metal may be used.", "The roll-on ball of the dispenser of the present invention will not become discolored or cause transferral of the original lip material to the ball in the dispenser if the ball on the dispenser of the present invention reflects light in the range of 350 to about 750 nm.", "More preferably, when the lip covering material reflects light at a wavelength in the range of about 400 to about 700 nm, the roll-on ball of the dispenser of the present invention will not be seen on the ball and/or will not cause transferral of the original lip material on the lips to the ball if the ball on the dispenser of the present invention reflects light in the range of 400 to about 700 nm.", "When the first lip material is a nonchromatic color the ball of the dispenser is preferably also a nonchromatic color.", "More preferably, where the nonchromatic color is a brown, the ball of the dispenser of the present invention should also be a brown.", "Where the nonchromatic color is a pink, the ball of the dispenser of the present invention should also preferably be a pink.", "Where the nonchromatic color is a magenta the ball of the dispenser of the present invention should also preferably be a magenta.", "Where there is no lip material on the lips presently preferably the roll-on ball should be the color of the lip covering material in the dispenser.", "In a preferred embodiment of the present invention for chromatic colors, the color of the ball should be in generally the same region of the spectrum as the color of the first lip material that was applied to the lips prior to the application of the lip gloss or other topical lip treatment.", "When this occurs any transferral of the original lip material is masked by the color of the ball.", "This is demonstrated by the following prophetic examples: EXAMPLE 1 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 600 to about 700 nm.", "If the color of the ball on an applicator is selected so that it also reflects light at a wave length in the range of about 600 to about 700 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 2 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 600 to about 700 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 600 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 3 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 580 to about 650 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 580 nm to about 650 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 4 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 580 to 650 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 580 nm and 650 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 5 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 550 to 600 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 550 nm to about 600 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 6 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 550 to 600 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 550 nm and 600 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 7 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 500 to 580 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 500 nm to about 580 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 8 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 500 to 580 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 500 nm and 580 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 9 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 450 to 550 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 450 nm to about 550 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 10 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 450 to 550 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 450 nm and 550 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 11 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 400 to 500 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 400 nm to about 500 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 12 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 400 to 500 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 500 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 13 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 650 to about 700 nm.", "If the color of the ball on an applicator is selected so that it also reflects light at a wave length in the range of about 650 to about 700 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 14 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 650 to about 700 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 650 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 15 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 600 to about 650 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 600 nm to about 650 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 16 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 600 to 650 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 600 nm and 650 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 17 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 500 to 600 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 500 nm to about 600 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 18 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 500 to 600 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 500 nm and 600 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 19 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 500 to 550 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 500 nm to about 550 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 20 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 500 to 550 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 500 nm and 550 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 21 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 450 to 500 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 450 nm to about 500 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 22 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 450 to 500 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 400 to about 450 nm and 500 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 23 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 400 to 450 nm.", "If the color of the ball on an applicator is selected so that it reflects light at a wave length in the range of about 400 nm to about 450 nm any transferal of the original lipstick material will be masked by the color of the ball.", "EXAMPLE 24 A lipstick is applied to the lips of a consumer.", "This lipstick has a color that reflects light at a wave length of about 400 to 450 nm.", "If the color of the ball on an applicator is selected so that it absorbs light at a wave length in the range of about 450 nm to 700 nm, any transferal of the original lipstick material will be masked by the color of the ball.", "In addition to characterizing a color by its wavelength, the color of the ball may also be characterized, in many instances, by its Pantone Number.", "In the present invention depending on the color of the lip covering material, the ball color may include but is not limited to any one of the following Pantone colors or combinations thereof: Yellow C Yellow 012 C Orange 021 C Warm Red C Red 032 C Rubine Red C Rhodamine Red C Purple C Violet C Blue 072 Reflex Blue Process Blue C Green C Process yellow C Process Black C Process Magenta C Process Cyan C Hexachrome Yellow C Hexachrome Orange C Hexachrome Magenta C Hexachrome Cyan C Haxachrome Black C Hexachrome Green C Pantone 100 C to 399 C, 429C to 433C, 430C to 433C, 437 C -440 C, 441 C to 587 C, 600 C-732 C, 801 C-814 C, Pantonel1205 C, 1215 C, 1225 C, 1235 C, 1245 C, 1255 C, 1265 C, Pantone 1345 C, 1355 C, 1365 C, 1375 C, 1385 C, 1395 C, 1405 C Pantone 1485 C, 1495 C, 1505 C, 1525 C, 1535 C, 1545 C, 1555 C, 1565 C, 1575 C, 1585 C, 1595 C, 1605 C, 1615 C, 1625 C, 1635 C, 1645 C, 1655 C, 1665 C, 1675 C, 1685 C, 1765 C, 1775 C, 1785 C, 1795 C, 1805 C, 1815 C, 1767 C, 1777 C, 1787 C, 1797 C, 1807 C, 1817 C, 1895 C, 1905 C, 1915 C, 1925 C, 1935 C, 1945 C, 1955 C, 2365 C, 2375 C, 2385 C, 2395 C, 2405 C, 2415 C, 2425 C, 2562 C, 2572 C, 2582 C, 2592 C, 2602 C, 2612 C, 2622 C, 2563 C, 2573 C, 2583 C, 2593 C, 2603 C, 2613 C, 2623 C, 2567 C, 2577 C, 2587 C, 2597 C, 2607 C, 2617 C, 2627 C, 2635 C 2645 C, 2655 C, 2675 C, 2685 C, 2695 C, 2705 C, 2715 C, 2725 C, 2735 C, 2745 C, 2755 C, 2765 C, 2706 C, 2716 C, 2726 C, 2736 C, 2746 C, 2756 C, 2766 C, 2707 C, 2717 C, 2727 C, 2737 C, 2747 C, 2757 C, 2767 C, 2708 C, 2718 C, 2728 C, 2738 C, 2748 C, 2758 C, 2768 C, 2905 C, 2915 C, 2925 C, 2935 C, 2945 C, 2955 C, 2965 C, 2975 C, 2985 C, 2995 C, 3005 C, 3015 C, 3025 C, 3035 C, 3105 C, 3115 C, 3125 C, 3135 C, 3145 C, 3155 C, 3165 C, 3242 C, 3252 C, 3262 C, 3272 C, 3282 C, 3292 C, 3302 C, 3245 C, 3255 C, 3265 C, 3275 C, 3285 C, 3295 C, 3305 C, 3248 C, 3258 C, 3268 C, 3278 C, 3288 C, 3298 C, 3308 C, 3935 C, 3945 C, 3955 C, 3965 C, 3975 C, 3985 C, 3995 C, 4485 C, 4495 C, 4505 C, 4515 C, 4525 C, 4535 C, 4545 C, 4625 C, 4635 C, 4645 C, 4655 C, 4665 C, 4675 C, 4685 C, 4695 C, 4705 C, 4715 C, 4725 C, 4735 C, 4745 C, 4755 C, 4975 C, 4985 C, 4995 C, 5005 C, 5015 C, 5025 C, 5035 C, 5115 C, 5125 C, 5135 C, 5145 C, 5155 C, 5165 C, 5175 C, 5185 C, 5195 C, 5205 C, 5215 C, 5225 C, 5235 C, 5245 C, 5255 C, 5265 C, 5275 C, 5285 C, 5295 C, 5305 C, 5315 C, 5395 C, 5405 C, 5415 C, 5425 C, 5435 C, 5445 C, 5455 C, 5463 C, 5473 C, 5483 C, 5493 C, 5503 C, 5513 C, 5523 C, 5467 C, 5477 C, 5487 C, 5497 C, 5507 C, 5517 C, 5527 C, 5535 C, 5545 C, 5555 C, 5565 C, 5575 C, 5585 C, 5595 C, 5743 C, 5753 C, 5763 C, 5773 C, 5783 C, 5793 C, 5803 C, 5747 C, 5757 C, 5767 C, 5777 C, 5787 C, 5797 C, 5807 C, 5815 C, 5825 C, 5835 C, 5845 C, 5855 C, 5865 C, 5875 C Black 2C, 3C, 4C, 5C, 6C, 7C Warm Gray 5C-11C Yellow U Yellow 012 U Orange 021 U Warm Red U Red 032 U Rubine Red U Rhodamine Red U Purple U Violet U Blue 072 U Reflex Blue U Process Blue U Green U Process yellow U Process Magenta U Process Cyan U Process Black U Hexachrome Yellow U Hexachrome Orange U Hexachrome Magenta U Hexachrome Black U Hexachrome Cyan U Hexachrome Green U Pantone 100 U to 399 U, 429U to 433U, 430U to 433U, 437U to 440 U, 441 U to 587 U, 600 U -732 U, 801 U-814 U, Pantone 1206 U, 1215 U, 1225 U, 1235 U, 1245 U, 1255U, 1265 U, Pantone 1345 U, 1355 U, 1365 U, 1375 U, 1385 U, 1395 U, 1405 U Pantone 1485 U, 1495 U, 1505 U, 1525 U, 1535 U, 1545 U, 1555 U, 1565 U, 1575 U, 1585 U, 1595 U, 1605 U, 1615 U, 1625 U, 1635 U, 1645 U, 1655 U, 1665 U, 1675 U, 1685 U, 1765 U, 1775 U, 1785 U, 1795 U, 1805 U, 1815 U, 1767 U, 1777 U, 1787 U, 1797 U, 1807 U, 1817 U, 1895 U, 1905 U, 1915 U, 1925 U, 1935 U, 1945 U, 1955 U, 2365 U, 2375 U, 2385 U, 2395 U, 2405 U, 2415 U, 2425 U, 2562 U, 2572 U, 2582 U, 2592 U, 2602 U, 2612 U, 2622 U, 2563 U, 2573 U, 2583 U, 2593 U, 2603 U, 2613 U, 2623 U, 2567 U, 2577 U, 2587 U, 2597 U, 2607 U, 2617 U, 2627 U, 2635 U, 2645 U, 2655 U, 2675 U, 2685 U, 2695 U, 2705 U, 2715 U, 2725 U, 2735 U, 2745 U, 2755 U, 2765 U, 2706 U, 2716 U, 2726 U, 2736 U, 2746 U, 2756 U, 2766 U, 2707 U, 2717 U, 2727 U, 2737 U, 2747 U, 2757 U, 2767 U, 2708 U, 2718 U, 2728 U, 2738 U, 2748 U, 2758 U, 2768 U, 2905 U, 2915 U, 2925 U, 2935 U, 2945 U, 2955 U, 2965 U, 2975 U, 2985 U, 2995 U, 3005 U, 3015 U, 3025 U, 3035 U, 3105 U, 3115 U, 3125 U, 3135 U, 3145 U, 3155 U, 3165U, 3242 U, 3252 U, 3262 U, 3272 U, 3282 U, 3292 U, 3302 U, 3245 U, 3255 U, 3265 U, 3275 U, 3285 U, 3295 U, 3305 U, 3248 U, 3258 U, 3268 U, 3278 U, 3288 U, 3298 U, 3308 U, 3935 U, 3945 U, 3955 U, 3965 U, 3975 U, 3985 U, 3995 U, 4485 U, 4495 U, 4505 U, 4515 U, 4525 U, 4535 U, 4545 U, 4625 U, 4635 U, 4645 U, 4655 U, 4665 U, 4675 U, 4685 U, 4695 U, 4705 U, 4715 U, 4725 U, 4735 U, 4745 U, 4755 U, 4975 U, 4985 U, 4995 U, 5005 U, 5015 U, 5025 U, 5035 U, 5115 U, 5125 U, 5135 U, 5145 U, 5155 U, 5165U, 5175 U, 5185 U, 5195 U, 5205 U, 5215 U, 5225 U, 5235 U, 5245 U, 5255 U, 5265 U, 5275 U, 5285 U, 5295 U, 5305 U, 5315 U, 5395 U, 5405 U, 5415 U, 5425 U, 5435 U, 5445 U, 5455 U, 5463 U, 5473 U, 5483 U, 5493 U, 5503 U, 5513 U, 5523 U, 5467 U, 5477 U, 5487 U, 5497 U, 5507 U, 5517 U, 5527 U, 5535 U, 5545 U, 5555 U, 5565 U, 5575 U, 5585 U, 5595 U, 5743 U, 5753 U, 5763 U, 5773 U, 5783 U, 5793 U, 5803 U, 5747 U, 5757 U, 5767 U, 5777 U, 5787 U, 5797 U, 5807 U, 5815 U, 5825 U, 5835 U, 5845 U, 5855 U, 5865 U, 5875 U Black 2U, 3U, 4U, 5U, 6U, 7U, and Warm Gray 5U-11U." ]
FIELD OF THE INVENTION [0001] The present invention relates to simulating a solid oxide fuel cell (SOFC); more particularly, relates to replacing a SOFC through a simulation to obtain electric characteristics of the SOFC and thus to save cost on developing the SOFC. DESCRIPTION OF THE RELATED ART [0002] Fuel cell has high efficiency on supplying power with relatively low cost. The fuel cell mainly uses hydrogen and oxygen to process an electrical reaction for producing electricity. Different fuel cells supplies different electricity to small facilities or even a big power plant. Among the fuel cells, SOFC has the best efficiency. Moreover, SOFC can be operated at a high temperature between 600 Celsius degrees (° C.) and 1000° C., and has a high-temperature exhaust. [0003] However, its technology threshold is the highest as well. Unit cost of SOFC is pretty high. And its structure is not strong that it can be broken and not afford to serious operations. In addition, tests during developing SOFC are quite often. A big change on a factor of the SOFC may ruin the SOFC. As a result, cost for developing a SOFC is high. Hence, the prior art does not fulfill all users' requests on actual use. SUMMARY OF THE INVENTION [0004] The main purpose of the present invention is to replace a SOFC through a simulation to obtain electric characteristics and thus to save cost for developing the SOFC. [0005] To achieve the above purpose, the present invention is a simulator of SOFC for electric characteristics, comprising a contacting unit comprising an anode part and a cathode part; a sensing unit connecting to the anode part and the cathode part; a sense analysis unit connecting to the sensing unit; and a load unit connecting to the sense analysis unit, where the sense analysis unit comprises a first A/D converter connecting to the sensing unit, an analysis unit connecting to the first A/D converter, a D/A converter connecting to the analysis unit, a power supply unit connecting to the D/A converter and a second A/D converter connecting to the power supply unit. Accordingly, a novel simulator of SOFC for electric characteristics is obtained. BRIEF DESCRIPTION OF THE DRAWINGS [0006] The present invention will be better understood from the following detailed description of the preferred embodiment according to the present invention, taken in conjunction with the accompanying drawings, in which [0007] FIG. 1 is the view showing the preferred embodiment according to the present invention; and [0008] FIG. 2 is the view showing the simulation using the preferred embodiment. DESCRIPTION OF THE PREFERRED EMBODIMENT [0009] The following description of the preferred embodiment is provided to understand the features and the structures of the present invention. [0010] Please refer to FIG. 1 and FIG. 2 , which are views showing a preferred embodiment according to the present invention and a simulation using the preferred embodiment. As shown in the figures, the present invention is a simulator of SOFC for electric characteristics, comprising a contacting unit 1 , a sensing unit 2 , a sense analysis unit 3 and a load unit 4 , where a solid oxide fuel cell (SOFC) is replaced with the present invention to test electric characteristics of the SOFC for saving cost for developing the SOFC. [0011] The contacting unit 1 comprises an anode part 11 and a cathode part 12 . [0012] The sensing unit 2 is connected with the anode part 11 and the cathode part 12 of the contacting unit 1 . [0013] The sense analysis unit 3 comprises a first analog/digital (A/D) converter 32 , an analysis unit 33 , a digital/analog (D/A) converter 34 , a power supply unit 35 and a second A/D converter 31 , where the analysis unit comprises a temperature calculation module 331 , a composition calculation module 332 and an electrochemical calculation module 333 . [0014] Thus, a novel simulator of SOFC for electric characteristics is obtained. [0015] On using the present invention, a device using battery 1 is connected with the contacting unit 1 , where fuels in the anode part 11 and the cathode part 12 of the contacting unit 1 are processed with a combined combustion and mixing. The sensing unit 2 senses a pressure, a plurality of component ratios and a temperature of the anode part 11 and the cathode part 12 of the contacting unit 1 . Physical quantities of the pressure, the component ratios and the temperature are converted into digital signals by the first A/D converter 32 to be transferred to the analysis unit 33 . Then electric characteristics obtained are converted into analog signals by the D/A converter 34 to be transferred to the power supply unit 35 . Then a voltage and a current returned by the power supply unit 35 are converted into digital signals by the second A/D converter 31 to be transferred to the analysis unit 33 . Data are then compared, analyzed and calculated by the temperature calculation module 331 , the composition calculation module 332 and the electrochemical calculation module 333 . Then data are converted into analog signals by the D/A converter 34 to be transferred to the power supply unit 35 . And the analysis unit 33 controls supplies of voltage and current through an iterative operation at time intervals. Finally, a voltage and a current are outputted to the load unit 4 to be adjusted. [0016] To sum up, the present invention is a simulator of SOFC for electric characteristics, where a SOFC is replaced through a simulation to obtain electric characteristics and thus to save cost on testing the SOFC. [0017] The preferred embodiment herein disclosed is not intended to unnecessarily limit the scope of the invention. Therefore, simple modifications or variations belonging to the equivalent of the scope of the claims and the instructions disclosed herein for a patent are all within the scope of the present invention.
A simulator is used for developing a solid oxide fuel cell (SOFC). Through the simulator, electrical characteristics of the SOFC are examined. Thus, with the simulator, cost for developing the SOFC is saved.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "FIELD OF THE INVENTION [0001] The present invention relates to simulating a solid oxide fuel cell (SOFC);", "more particularly, relates to replacing a SOFC through a simulation to obtain electric characteristics of the SOFC and thus to save cost on developing the SOFC.", "DESCRIPTION OF THE RELATED ART [0002] Fuel cell has high efficiency on supplying power with relatively low cost.", "The fuel cell mainly uses hydrogen and oxygen to process an electrical reaction for producing electricity.", "Different fuel cells supplies different electricity to small facilities or even a big power plant.", "Among the fuel cells, SOFC has the best efficiency.", "Moreover, SOFC can be operated at a high temperature between 600 Celsius degrees (° C.) and 1000° C., and has a high-temperature exhaust.", "[0003] However, its technology threshold is the highest as well.", "Unit cost of SOFC is pretty high.", "And its structure is not strong that it can be broken and not afford to serious operations.", "In addition, tests during developing SOFC are quite often.", "A big change on a factor of the SOFC may ruin the SOFC.", "As a result, cost for developing a SOFC is high.", "Hence, the prior art does not fulfill all users'", "requests on actual use.", "SUMMARY OF THE INVENTION [0004] The main purpose of the present invention is to replace a SOFC through a simulation to obtain electric characteristics and thus to save cost for developing the SOFC.", "[0005] To achieve the above purpose, the present invention is a simulator of SOFC for electric characteristics, comprising a contacting unit comprising an anode part and a cathode part;", "a sensing unit connecting to the anode part and the cathode part;", "a sense analysis unit connecting to the sensing unit;", "and a load unit connecting to the sense analysis unit, where the sense analysis unit comprises a first A/D converter connecting to the sensing unit, an analysis unit connecting to the first A/D converter, a D/A converter connecting to the analysis unit, a power supply unit connecting to the D/A converter and a second A/D converter connecting to the power supply unit.", "Accordingly, a novel simulator of SOFC for electric characteristics is obtained.", "BRIEF DESCRIPTION OF THE DRAWINGS [0006] The present invention will be better understood from the following detailed description of the preferred embodiment according to the present invention, taken in conjunction with the accompanying drawings, in which [0007] FIG. 1 is the view showing the preferred embodiment according to the present invention;", "and [0008] FIG. 2 is the view showing the simulation using the preferred embodiment.", "DESCRIPTION OF THE PREFERRED EMBODIMENT [0009] The following description of the preferred embodiment is provided to understand the features and the structures of the present invention.", "[0010] Please refer to FIG. 1 and FIG. 2 , which are views showing a preferred embodiment according to the present invention and a simulation using the preferred embodiment.", "As shown in the figures, the present invention is a simulator of SOFC for electric characteristics, comprising a contacting unit 1 , a sensing unit 2 , a sense analysis unit 3 and a load unit 4 , where a solid oxide fuel cell (SOFC) is replaced with the present invention to test electric characteristics of the SOFC for saving cost for developing the SOFC.", "[0011] The contacting unit 1 comprises an anode part 11 and a cathode part 12 .", "[0012] The sensing unit 2 is connected with the anode part 11 and the cathode part 12 of the contacting unit 1 .", "[0013] The sense analysis unit 3 comprises a first analog/digital (A/D) converter 32 , an analysis unit 33 , a digital/analog (D/A) converter 34 , a power supply unit 35 and a second A/D converter 31 , where the analysis unit comprises a temperature calculation module 331 , a composition calculation module 332 and an electrochemical calculation module 333 .", "[0014] Thus, a novel simulator of SOFC for electric characteristics is obtained.", "[0015] On using the present invention, a device using battery 1 is connected with the contacting unit 1 , where fuels in the anode part 11 and the cathode part 12 of the contacting unit 1 are processed with a combined combustion and mixing.", "The sensing unit 2 senses a pressure, a plurality of component ratios and a temperature of the anode part 11 and the cathode part 12 of the contacting unit 1 .", "Physical quantities of the pressure, the component ratios and the temperature are converted into digital signals by the first A/D converter 32 to be transferred to the analysis unit 33 .", "Then electric characteristics obtained are converted into analog signals by the D/A converter 34 to be transferred to the power supply unit 35 .", "Then a voltage and a current returned by the power supply unit 35 are converted into digital signals by the second A/D converter 31 to be transferred to the analysis unit 33 .", "Data are then compared, analyzed and calculated by the temperature calculation module 331 , the composition calculation module 332 and the electrochemical calculation module 333 .", "Then data are converted into analog signals by the D/A converter 34 to be transferred to the power supply unit 35 .", "And the analysis unit 33 controls supplies of voltage and current through an iterative operation at time intervals.", "Finally, a voltage and a current are outputted to the load unit 4 to be adjusted.", "[0016] To sum up, the present invention is a simulator of SOFC for electric characteristics, where a SOFC is replaced through a simulation to obtain electric characteristics and thus to save cost on testing the SOFC.", "[0017] The preferred embodiment herein disclosed is not intended to unnecessarily limit the scope of the invention.", "Therefore, simple modifications or variations belonging to the equivalent of the scope of the claims and the instructions disclosed herein for a patent are all within the scope of the present invention." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority from U.S. Provisional Application No. 62/162,215 filed on May 15, 2015, entitled “Route Based Vehicle Speed Optimization for Fuel Efficiency”, which is hereby fully incorporated by reference. This application also claims priority from U.S. Provisional Application No. 62/162,258 filed on May 15, 2015, entitled “Route Aware Speed Control for Fuel Efficiency”, which is hereby fully incorporated by reference. This application further claims priority from U.S. Provisional Application No. 62/162,287 filed on May 15, 2015, entitled “Elevation Querying System”, which is hereby fully incorporated by reference. [0002] Further, this application is related to co-pending U.S. application Ser. No. ______, (Attorney Docket Number MGL-1602-US) filed May 11, 2016, entitled “Elevation Query Systems for Vehicular Route Optimization and Methods thereof”, which is hereby fully incorporated by reference. [0003] Additionally, this application is related to co-pending U.S. application Ser. No. ______, (Attorney Docket Number MGL-1603-US) filed May 11, 2016, entitled “System and Methods for Efficient Resource Management During Vehicular Journeys”, which is hereby fully incorporated by reference. BACKGROUND [0004] The present invention relates to systems and methods for efficiently deploying valuable resources, such as cost and duration, especially during extended vehicular trips. [0005] While many vehicles available today offer conveniences such as cruise control, they provide few options for assisting drivers interested in dynamically optimizing fuel efficiency. For example, cruise control works reasonably well for maintaining a constant speed on a straight and flat interstate freeway with moderate traffic. In newer and better equipped vehicles, adaptive cruise control enables these drivers to maintain appropriately safe spacing between vehicles when the vehicle ahead changes speed, while lane departure warning system alerts inattentive drivers who drift from their intended lane of traffic. However, the general goal of the current vehicular control systems is to minimize driver workload and/or to enhance driver safety. [0006] Some driver-agnostic and route-agnostic attempts at reducing fuel consumption do exist, and they include “one-size-fits-all” strategies such as capping the rate of acceleration or shifting gears at more efficient preset speeds, often marketed as “ECO” driving mode. However these “ECO” modes substantially compromise vehicular performance, and also ignore individual driver preferences and actual routes driven, thereby adversely impacts drivers' overall experience. [0007] It is therefore apparent that an urgent need exists for systems and methods targeted at increasing efficiency of vehicles while dynamically taking into consideration real-time route characteristics. With the average cost of new cars in the United States now exceeding $30,000, existing vehicles are expected to remain in service for ten or more years. Hence, in addition to improving the dynamic efficiency of new vehicles, such improved systems and methods enable a large number of existing vehicles to be retrofitted and transformed into dynamically efficient vehicles. SUMMARY [0008] To achieve the foregoing and in accordance with the present invention, systems and methods for dynamically and efficiently operating a vehicle along a route in real-time is provided. [0009] In one embodiment, a vehicular glide solver receives a requested route defined by at least one route parameter. The solver optimizes the requested route using vehicular optimization criteria, wherein the optimization includes analysis of at least one data set pertaining to the requested route, and provides a vehicular glide schedule for discrete points along the requested route in response to the route optimization. The solver dynamically adjusts the vehicular glide schedule in response to a change in one of the at least one data set. [0010] Note that the various features of the present invention described above may be practiced alone or in combination. These and other features of the present invention will be described in more detail below in the detailed description of the invention and in conjunction with the following figures. BRIEF DESCRIPTION OF THE DRAWINGS [0011] In order that the present invention may be more clearly ascertained, some embodiments will now be described, by way of example, with reference to the accompanying drawings, in which: [0012] FIGS. 1-4 are block diagrams illustrating one embodiment of a dynamic vehicular resource optimization system in accordance with the present invention; [0013] FIGS. 5-7 are flowcharts illustrating the embodiment of the dynamic vehicular resource optimization system of FIGS. 1-4 ; [0014] FIGS. 8A-8C are block diagrams illustrating three alternative implementations of a glide controller for the dynamic vehicular resource optimization system of FIGS. 1-4 ; [0015] FIGS. 9 and 10A-10B illustrate one embodiment of an elevatier for the dynamic vehicular resource optimization system of FIGS. 1-4 ; and [0016] FIGS. 11-13 are screenshots illustrating the embodiment of the dynamic vehicular resource optimization system of FIGS. 1-4 . DETAILED DESCRIPTION [0017] The present invention will now be described in detail with reference to several embodiments thereof as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the present invention. It will be apparent, however, to one skilled in the art, that embodiments may be practiced without some or all of these specific details. In other instances, well known process steps and/or structures have not been described in detail in order to not unnecessarily obscure the present invention. The features and advantages of embodiments may be better understood with reference to the drawings and discussions that follow. [0018] Aspects, features and advantages of exemplary embodiments of the present invention will become better understood with regard to the following description in connection with the accompanying drawing(s). It should be apparent to those skilled in the art that the described embodiments of the present invention provided herein are illustrative only and not limiting, having been presented by way of example only. All features disclosed in this description may be replaced by alternative features serving the same or similar purpose, unless expressly stated otherwise. Therefore, numerous other embodiments of the modifications thereof are contemplated as falling within the scope of the present invention as defined herein and equivalents thereto. Hence, use of absolute and/or sequential terms, such as, for example, “always,” “will,” “will not,” “shall,” “shall not,” “must,” “must not,” “first,” “initially,” “next,” “subsequently,” “before,” “after,” “lastly,” and “finally,” are not meant to limit the scope of the present invention as the embodiments disclosed herein are merely exemplary. [0019] The present invention relates to systems and methods for optimizing a vehicle's route and Glide schedule using information related but not limited to traffic, time, cost, weather, vehicular sensor data, cost, and refueling/recharging. In particular, the present invention is directed to the novel methods and systems to optimize the route of a transportation vehicle based on optimization preferences, and provide the vehicle user and the vehicle with an optimized route based on the optimization preferences. Additionally, the present invention is directed to the novel methods and systems that enable a user to temporarily relinquish acceleration and braking (regenerative deceleration, engine braking, and friction braking) to the present invention for the purpose of increasing a vehicle's efficiency and optimizing one or more of a vehicle route's parameters (e.g. time, cost); this could be thought of as an advanced or “smart” cruise control. Additionally, the present invention is directed to the novel methods and systems that enable a transportation infrastructure (namely vehicular) to optimize one of many parameters, including but not limited to, traffic flow, total throughput, and lane avoidance/clearance, by providing vehicles with instructions directed at how to manipulate driving behaviors. [0020] The following discussion serves to explain the methods and systems of the present invention. There are multiple examples throughout the discussion that aid in the explanation of certain features or methods the present invention has or uses. For example, this discussion is primarily centered on the automotive transportation industry and movement in 2-dimensional space (constrained to roads). This should not limit the scope of application for the present invention. The systems and methods described here may be applied to planes, boats, submersibles, and spacecraft. Many of these modes of transportation are not limited in movement to 2-dimensions; it follows that the discussion should not limit the present invention to operating in the vehicle transportation sector, nor in 2-dimensional space. [0021] FIG. 1 shows one possible embodiment of the Glide System 100 . Communication between the Glide Servers 110 , 170 and Glide enabled devices 131 , 132 . . . 139 , 140 , 150 may occur over a WAN (Wide Area Network) 120 . Although FIG. 1 depicts Glide enabled devices 131 , 132 . . . 139 , 140 , 150 as motorized vehicles and traffic related infrastructure, this should not limit the scope of Glide enabled devices. [0022] There may be multiple instances of the Glide Servers 110 , 170 . These different instances of the servers may serve different purposes or may store different data. As an example, one set of Glide Servers 110 may be responsible for data pertaining to route optimization, while another instance of the Glide Servers 170 may be responsible only for providing firmware updates to Glide Controllers 144 . This may mean that a Glide Controller 144 will access Glide Servers 110 exclusively when performing route optimization. It would then follow that, when requesting firmware updates or periodic (monthly, quarterly, yearly) data refreshing, a Glide Controller 144 may only access Glide Server 170 . [0023] Throughout the rest of this discussion, Glider Servers 110 in FIG. 1 will be referenced when route data is being discussed, and Glider Servers 170 in FIG. 1 will be referenced when firmware updates and locally stored data refreshing are being discussed. This distinction between the two different blocks of FIG. 1 should in no way limit the number or responsibilities of different instances of the Glide Servers. [0024] Communication 160 in the Glide System 100 may happen between Glide enabled devices 131 , 132 . . . 139 , 140 , 150 and the Glide Servers 110 , 120 or between Glide enabled devices 131 , 132 . . . 139 , 140 , 150 . Communication 160 should not be limited to the above two cases. Communication 160 in the Glide System 100 may include but is not limited to, 4G and 5G cellular communication, DSRC, WiFi, ZigBee, and Bluetooth. [0025] There may be multiple mode variations that a Glide Controller 144 may operate in. These may include but are not limited to, a subscription-based model; a stand-alone configuration; and OEM licensed software. The mode variation that a Glide Controller 144 is operating in may determine the Glide Servers 110 , 170 that specific Glide Controller 144 has access to. [0026] In the subscription-based model, the Glide Controller 144 in a Glide enabled device 131 , 132 . . . 139 , 140 , 150 may send and receive pertinent data to and from the Glide Servers 110 to be used to optimize a route for the desired parameters. The subscription based model may allow Glide Controllers 144 to communicate 160 in real-time with the Glide Servers 110 to gain new information pertinent to solving the route optimization. This model may be similar to OnStar systems where the user 141 may pay a subscription fee for continuous use of the Glide Servers 110 . [0027] In the stand-alone application, the Glide Controller 144 in the Glide enabled device 131 , 132 . . . 139 , 140 , 150 may not communicate 160 with the Glide Servers 110 , but may rather solve the route optimization using data included locally on the Glide Controller 144 . In this way, the Glide Controller 144 would not receiver data from the Glide Servers 110 that is pertinent to solving the route optimization. This stand-alone configuration may allow for a Glide Controller 144 to download firmware updates from the Glide Servers 170 . These firmware updates may include firmware that runs on a Glide Controller 144 as well as updates to the data stored locally on the Glide Controller 144 that the controller uses to solve the route optimization. This model may be compared to a GPS unit where the unit periodically downloads updates, but it relies on internal data for functionality. [0028] A third possibility is for the Glide Controller 144 to be licensed to OEM (Original Equipment Manufacturers) for use in propriety or “in-house” developed products. An example of this may be the Glide software being installed directly into the electronic vehicular control unit (e.g. ECU) 142 of an OEM vehicle instead of as an after-market add-on. In this realization, the Glide functionality may operate in either the connected or stand-alone mode. [0029] These three models should not be considered the only embodiment variations that Glide Controllers 144 may operate in. It should be noted that all embodiments of the Glide System 100 may include the ability to solve the route optimization problem, regardless of if it is a connected system, stand-alone, licensed to an outside party or any other embodiment the system might assume. [0000] I. User and/or Vehicle Interfaces [0030] FIG. 1 shows the Glide System 100 with Glide enabled devices 131 , 132 . . . 139 , 140 , 150 . Glide enabled vehicle 140 shows that the Glide Controller 144 may include a Glide User Interface 143 . The Glide User Interface 143 may refer generally to a module capable of providing the user 141 a way to import route information into the Glide Controller 144 . More specifically, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data. [0031] The Glide User Interface 143 may be a user's 141 cellular device, tablet or laptop computer. The Glide User Interface 143 may not necessarily be installed in the Glide enabled device 140 , but may be a device that is connected via a wireless communications protocol and WAN to the Glide Controller 144 , the Glide enabled device 140 , or the Glide WAN 120 . In this way, the Glide Controller 144 may be controlled remotely (outside of the Glide enabled device 140 ). [0032] The Glide User Interface 143 may be used to receive route parameters, preferences and general data from the User 141 ; it may also be used to display information to the User 141 . Information that the Glide User Interface 143 may report the user may include but is not limited to, trip duration; estimated time of arrival (ETA); trip cost (tolls, fuel consumption cost, etc.); current vehicle speed; next target speed; next target location; trip efficiency normalized by distance relative to other trips taken; trip efficiency normalized by distances relative to the same trip taken without the Glide System 100 ; the next driving instruction; or warning of hazards along the route. [0033] The information that the Glide User Interface 143 may display should in no way be limited by the above list. The Glide User Interface 143 may also be integrated into the vehicle's infotainment suite. In this realization, the Glide User Interface 143 may be tasked with displaying other vehicle related information including but not limited to, navigation maps and directions; maintenance alerts; and entertainment related information. [0034] FIG. 2 shows how a Glide Controller 144 may interface with the Glide enabled device 131 , 132 . . . 139 , 140 , 150 that it is installed into and the user 141 of that device (if applicable). The Glide Controller may communicate with multiple vehicle peripheral systems 145 , 142 , 210 , 143 including but not limited to, vehicular sensors (e.g. GPS, radar, optical sensors, wheel speed sensors, accelerometers, gyroscopes and strain gauges) 145 ; the electronic vehicular control unit (e.g. ECU and cruise control specific controller) 142 ; and the vehicular control interface (e.g. accelerator and brake pedals and cruise controls) 210 . [0035] FIG. 2 depicts the data between the Glide Controller 144 and vehicle's peripherals 145 , 142 , 210 , 143 may be bidirectional. In this case, the Glide Controller 144 may take information from the peripherals while also sending data to or manipulating them. [0036] The Glide Controller 144 may integrate into the Glide enabled device 131 , 132 . . . 139 , 140 , 150 in multiple ways. The following discussion is specific to integration into a vehicle but may also apply for integration into other devices; further, it should not be concluded that these are the only ways the Glide Controller 144 may integrate into a physical system. [0037] FIG. 3 shows one way the Glide Controller 144 may be integrated into the electronics of a vehicle. The Glide Controller 144 may be connected to any of or multiple of the vehicle's CAN busses 360 , which means it may be able to take data from and inject data onto the vehicle's communication bus 360 . In this way, the Glide Controller 144 may be able to manipulate the throttle request of the vehicle by adding specific messages onto the CAN bus 360 . In addition to manipulating the throttle request, the Glide Controller 144 may be able to manipulate other sensors or modules in the vehicle. Other information the Glide Controller 144 may manipulate may include but is not limited to, Batter Management System information (tractive battery voltage, tractive battery current, output and input tractive battery power); cylinder activation; braking (regenerative deceleration, engine braking, friction braking); gear and neutral selection; 4 wheel, 2 wheel, and all-wheel drive selection; enabling and disabling manufacturer eco modes; and specifying a power plant to use (electric or gas) in hybrid systems. This may also allow the Glide Controller 144 to collect information from the vehicular sensors 310 , 320 , 330 , 340 , 350 , 370 . The vehicular sensors shown in FIG. 3 are representative only and should not limit the quantity or scope of the sensors that a Glide Controller 144 may take information from or give information to. [0038] The Glide Controller 144 may physically connect to the vehicle's accelerator pedal 210 . FIG. 4 shows the functional blocks for the Speed Control Interface 440 interacting with the vehicle's user interface (pedals) 210 . In this way, the accelerator pedal 210 may be physically actuated by the Glide Controller 144 to adjust the acceleration of the vehicle to match the route optimization that the Glide Controller 144 has been tasked with carrying out. [0039] The Glide Controller 144 may physically actuate the vehicle's accelerator pedal by using a vacuum servomotor that is driven by a microcontroller. In this way, the Glide Controller 144 may directly actuate the vehicle's accelerator pedal 210 through an electro-mechanical output. This is just an example of one way to interface with the vehicle's pedal and should not be considered an exclusive or limiting example. [0040] The Glide Controller 144 may physically connect to the vehicle's throttle cable. It may connect to the cable that is physically connected to the accelerator pedal, or it may connect to the throttle cable controlled by the vehicle's cruise control system. In this way, the Glide Controller 144 may physically actuate the vehicle's accelerator cable, which will influence the vehicle's speed. [0041] The Glide Controller's 144 Speed Control Interface 440 may actuate the throttle cable(s) via a vacuum servomotor and microcontroller, similar to the connection to the accelerator pedal that was just discussed. This is just an example of one way to interface with the throttle cable(s) and should not be considered an exclusive or limiting example. [0042] The Speed Control Interface 440 may be responsible for processing the Glide Schedule received from the Glide Solver 410 . This Glide Schedule may be a set of discretized points that pertain to locations along the requested route. These points may be the same optimization points that the Glide Solver 410 produces. The Speed Control Interface 440 may not be the only method for manipulating the performance of the vehicle. The Speed Control Interface 440 may also be responsible for producing Glide control messages. These control messages may be electronic and used to interface with the vehicular electronic communications. [0043] In an embodiment where the Speed Control Interface 440 is not used to manipulate the vehicle, or the vehicular controls, a User 141 may be presented with instructions or a Glide Schedule. In this way, the Glide Schedule may be presented to the User 141 via instructions pertaining to how to operate the vehicle to adhere to the optimization produced by the Glide Controller 144 . [0044] This set of instructions (manual carrying out of the Glide Schedule) may be presented visually to the User 141 via the Glide User Interface 143 , or the instructions may be presented audibly to the User 141 , or the instructions may be presented via the vehicular GPS unit. The Glide Controller 144 should not be limited by these examples in how it may present instructions to the User 141 . [0045] The Speed Control Interface 440 may receive the Glide Schedule from a plurality of sources. In the embodiment where the Glide Controller 144 is present in the vehicle, the Speed Control Interface 440 may receive the Glide Schedule locally from the Glide Controller 144 . In the embodiment where the Glide Controller 144 and its functionality is carried out remotely (non-locally—e.g., on the Glide Servers), the Speed Control Interface 440 may receive the Glide Schedule from a remote device (Glide Servers). These two examples serve to explain that the Glide Schedule may be received from a plurality of sources and does not server to exclude sources that may provide the Glide Schedule. [0046] The Glide Schedule and Glide Schedule messages may be communicated via a plurality of methods. The messages may be communicated via one or multiple copper wire busses and protocols including but not limited to, UART, USART, I2C, EIA-232, CANbus, CANopen, and LIN. The messages may be communicated via one or multiple wireless communications protocols including but not limited to, cellular 3G, 4G and 4GLTE; WiFi; Bluetooth; and ZigBee. The Glide Schedule messages may also be communicated via an optical communications bus and protocol. These physical busses and messaging protocols serve as examples and should not serve as exclusive lists, but examples of possibilities. [0047] The Glide control messages may be sent via the same busses and protocols listed above. Again, this does not serve as an exclusive list for how glide control messages may be communicated, but an example of possibilities. [0048] While the example carried through in this description looks at manipulating the accelerator pedal of the vehicle, it should be noted that the Speed Control Interface 440 may manipulate a plurality of vehicle controls. These vehicular controls may include but are not limited to throttle (accelerator), brake, regenerative braking, de-acceleration, transmission controller, and power-train selection control. The Speed Control Interface 440 may receive Glide Schedules pertaining to the manipulation and control of any number of these or more vehicular controls. The Speed Control Interface 440 may produce any number of Glide control messages pertaining to and aimed at the control of any number of these or more vehicular controls. The Speed Controller 440 may manipulate multiple vehicular controls using multiple different methods (mechanical actuation and electronic control). [0049] While FIG. 3 shows the Glide Controller 144 interfacing with the vehicle electrically (by the vehicle's electronics communications bus 360 —e.g. CANbus), there are other electrical methods for the Glide Controller 144 to interact with the vehicular sensors 310 , 320 , 330 , 340 , 350 , 360 and the electronic vehicular control unit (e.g. ECU) 142 . The Speed Control Interface 440 may inject or send Glide control messages via the vehicular electronics communication bus 360 (e.g. CANbus). II. Glide Solver [0050] FIG. 8B shows one possible block diagram of the route processing side of the Glide System 100 . The Requesting Device 811 a may send a route request to the Request Manager 812 . The requested route may be defined by start, end and waypoints; start and end; or simply start or end. The Requesting Device 811 a may also define the route as GPS coordinates spaced at regular intervals along the route. [0051] The Requesting Device 811 a may be a User 141 , an application (via a smartphone, table, or computer). The Requesting Device 811 a may be the Glide User Interface 143 . Additionally, the Requesting Device 811 a could be the Glide WAN 120 , if a User 141 is accessing a Glide Controller 144 via the Glide WAN 120 . [0052] In the standalone embodiment of the system, all of the blocks shown in FIG. 8B may be present in the Glide Controller 144 that is installed in the Glide enabled device 131 , 132 . . . 139 , 140 , 150 ; in the connected embodiment, some, all, or none of these blocks may be present in Glide Controller 144 with the others present on the Glide Servers 110 . [0053] Returning to FIG. 8B , the request manager may then interact with both the Glide Solver 410 and the constraint databases 815 , 816 , 816 . . . 819 to provide the Glide Solver 410 with the information it needs to successfully complete the requested route optimization. [0054] The constraint databases 815 , 816 , 817 . . . 819 may include information related to but not limited by, elevation, drag force, road speed, road curvature, road conditions, traffic, and weather. The Glide Solver 410 may request data from these databases to aid in the optimization of the requested route. [0055] The constraint databases 815 , 816 , 817 . . . 819 may be stored on the Glide Servers 110 , locally on the Glide Controller 144 or in other locations accessible via the Glide System WAN 120 . Additionally, it may be possible to import constraint databases 815 , 816 , 817 . . . 819 into the Glide Controller 144 . An example of this could be data pertaining to a foreign country. The constraint data may be read from a media storage device that is connected to the Glide Controller 144 . [0056] In addition to the constraint databases 815 , 816 , 817 . . . 819 , the Glide Solver 410 and/or Request Manager 812 may request other information from the Glide Servers 110 , 170 , onboard memory or infrastructure servers. [0057] Infrastructure servers and their databases may provide the information related but not limited to current traffic conditions, traffic light timing, current throughput, current throughput goals, current lane throughput, current lane throughput goals, traffic accidents, accident avoidance instructions, and emergency vehicle avoidance instructions. [0058] Other Glide enabled vehicles 131 , 132 . . . 139 , 140 may be a source of additional information that the Glide Solver 410 or Request Manager 812 may request data from. [0059] Since the breadth of information the Glide Solver 410 and Request Manager 812 has access to is large, the data resources are clearly not limited to those mentioned above. [0060] Referring back to FIG. 8B , the Request Manager 812 receives a route from the Requesting Device 811 a , and then requests the necessary constraint information from the constraint databases 815 , 816 , 817 . . . 819 for the requested route. The Request Manager 812 sends the constraint information and any route parameters provided by the Requesting Device 811 a or other parameter sources to the Glide Solver 410 . [0061] The Glide Solver 410 , shown in FIG. 4 as part of the Glide Controller 144 , may include multiple algorithm blocks. Two of these blocks, shown in FIG. 4 , may be the Route Optimizer 420 and the Elevatier 430 . [0062] The Route optimizer 420 may be used in all variations of the Glide System 100 . As stated above, these may include, systems installed in vehicles, systems installed in transportation infrastructures, and systems operating in any of the modes discussed in this specification. [0063] When installed in a vehicle, the Route Optimizer 420 may work by minimizing any number of parameter vectors of the vehicle from the starting point to the ending point of the route. The flow diagrams presented in the figure set use the positive direction acceleration vector as an example; this should not serve as a limiting or exclusive example. In minimizing this positive acceleration vector, the Glide Solver 410 minimizes the energy consumption necessary to complete the requested route. The Glide Solver 410 may minimize the norm-2 of the positive acceleration for each point along the route, or the Glide Solver 410 may minimize a piecewise linear function of the acceleration for each point along the route. The method for optimization should not be limited to the two previously mentioned methods. Any method of optimization may be applied in the Glide Solver 410 . From these discrete acceleration points, the Glide Solver 410 may extrapolate and send discrete speeds that the vehicle should reach at predetermined points along the route to the Glide Controller 144 and Speed Control Interface 440 . [0064] The acceleration example carried through this discussion is just one of many parameters that the Glide Solver 410 and the Glide System 100 may optimize for. The discretized points that the Glide Solver 410 produces may be generally called a Glide Schedule. This Glide Schedule may include discretized points for any number of vehicle parameters. The Glide Schedule may pertain to but is not excluded by, acceleration, engine revolutions-per-minute (RPM), motor RPM, gear selection, powertrain selection, braking, and regeneration (regenerative braking). [0065] The acceleration example carried throughout this description should not limit the scope of the parameters that the Glide Solver 410 or the Glide System 100 may solve for, but rather the example should illustrate how the Glide Solver 410 and Glide System 100 go about optimizing for a given parameter. [0066] The Glide Solver 410 may minimize for multiple parameters. In this case, the Glide Solver 410 may minimize a weighted function of the multiple parameters. [0067] In addition to minimizing the necessary energy for the route, the Glide Solver 410 may use user-configurable options and vehicle type to optimize for other route metrics including but not limited to, monetary cost, temporal trip duration, and travel time spent idle. [0068] The monetary cost or a trip may include but is not limited to, vehicular operating cost, fuel cost, charging cost, and maintenance cost. [0069] When installed in the transportation infrastructure, the Route optimizer 420 may work much in the same way. It may also optimize for other metrics including but not limited to, vehicle throughput, traffic latency and prioritization for special/emergency vehicles. [0070] The Glide Schedule should not be thought of as a fixed solution. The Glide Controller 144 and Glide Solver 410 may continually adjust the Glide Schedule based on new or different data received. This data may be sensor data from one or more of the vehicular sensors, or this data may be received from the constraint databases 815 , 816 , 187 . . . 819 . In this way, the Glide System 100 is continually working, optimizing, and adjusting the Glide Schedule [0071] FIG. 5 and FIG. 6 show possible flow paths for the Glide System 100 from route request to route delivery. FIG. 5 shows a possible flow path for a Glide System 100 that is operating in the connected mode. This mode, as explained above, may denote that the Glide Controller 144 in the Glide enabled device 131 , 132 . . . 139 , 140 , 150 is connected to the Glide Servers 110 via the WAN 120 . FIG. 4B shows a possible flow path for a Glide System 100 that is operating without a final destination. This mode may denote that the Glide Controller 144 is simply looking a certain distance ahead of the current location and continually optimizing the route for the next x-miles. [0072] Step 511 in FIG. 5 describes the Requesting Device 811 a , 811 b sending route information and configuration data to the Request Manager 812 . The Requesting Device 811 a , 811 b may be any of a plethora of possible devices. In the simplest realization, the Requesting Device 811 a , 811 b may be a User 141 . The User 141 may input the route and configuration data via a Glide User Interface 143 . [0073] The User 141 may be prompted for different pieces of information related to the route to be requested. These pieces of information could include but are not limited to, starting and ending points of the route; waypoints throughout the route; and parameters to be optimized for. The Glide Controller 144 may provide (via the Glide User Interface 143 suggestions to the User 141 based on past routes or even other Glide Users with similar habits or destinations. [0074] The Glide Controller 144 may also predict the User's 144 routes and route preferences. An example of this may be predicting a route that is taken at 7:00 am every weekday morning with the starting point being the User's 141 home address, the ending point being the User's 141 work address and a waypoint at the local coffee shop. The Glide Controller 144 may predict this route and have the User's 141 typical preferences for this route auto-filled when the User 141 starts the system at 6:55 am. [0075] The Glide User Interface 143 may refer generally to a module capable of providing the User 141 a way to provide route information and parameters into the Glide Controller 144 . More specifically, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data. [0076] The Glide User Interface 143 may be a user's 141 cellular device, tablet or laptop computer. The Glide User Interface 143 may not necessarily be installed in the Glide enabled device 140 , but may be a device that is connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 , the Glide enabled device 140 , or the Glide WAN 120 . In this way, the Glide Controller 144 may be controlled remotely (outside of the Glide enabled device 140 ). This Glide User Interface 143 may be any device capable of accepting information from a User 141 . The Glide Use Interface 143 may include cellular phones, tablets, laptop computers or any other module capable of accepting inputs and communicating those inputs to the Request Manager 812 . [0077] In other realizations, the Requesting Device 811 a , 811 b may be a device similar to that of the Glide User Interface 143 . A User's 141 cellular phone, tablet, or laptop may be more than just the Glide User Interface 143 . The Requesting Device 811 b may not necessarily be installed in the Glide enabled device 131 , 132 . . . 139 , 140 , 150 , or it may not be integrated into the Glide Controller 144 . The Requesting Device 811 a , 811 b may be connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 or directly to the Request Manager 812 . [0078] In other realizations or embodiments, the Requesting Device 811 a , 811 b may be the traffic infrastructure 150 , or the Glide Servers 110 . [0079] Referring back to FIG. 5 , step 511 , the Requesting Device 811 a , 811 b (discussed above) may send the route configuration data to the Request Manager 812 . The route information from the Requesting Device 811 a , 811 b may be defined in a plurality of manners. [0080] The route information may be sent as a set of locations, starting, ending and waypoints in between; starting and ending; simply starting or simply ending. The route information may also be sent as a list of GPS points spaced along the desired route. [0081] Step 512 of FIG. 5 describes the Request Manager 812 inserting points along the route to gain the necessary granularity to accurately optimize the route. The purpose of this step is to create more data points for the Glide Solver 410 to calculate. More data points along the route means the Glide Solver 410 will be able to solve for more acceleration points, and this means the speed targets will have finer resolution. [0082] In step 512 of FIG. 5 , the Request Manager 812 may or may not insert additional points along the route. If the route data from step 511 was provided as a list of GPS points, and the Request Manager 812 determines the GPS points provide an adequate level of resolution (granularity), step 512 may not be carried out. [0083] Step 512 in FIG. 5 should not be limited to just the Request Manager 812 . In some embodiments of the Glide System 100 , the data insertion may be carried out by another functional block (e.g. the Glide Solver 410 ). [0084] In step 513 in FIG. 5 , the Request Manager 812 may fetch the necessary data from the constraint databases 815 , 816 , 817 . . . 819 . The constraint databases 815 , 816 , 817 . . . 819 may include information related to but not limited by, elevation, road speed, and road curvature. The Request Manager 812 may request data from the constraint databases 815 , 816 , 817 . . . 819 for each point along the requested route. These points may be the points created in step 512 , or they may be points provided by the Requesting Device 811 a , 811 b. [0085] The constraint databases 815 , 816 , 817 . . . 819 may be stored on the Glide Servers 110 , locally on the Glide Controller 144 , or in other locations accessible via the Glide System WAN 120 . Additionally, it may be possible to import constraint databases 815 , 816 , 817 . . . 819 into the Glide Controller 144 . The constraint data may also be read in from a media storage device that is connected to the local Glide Controller 144 . [0086] In addition to the constraint databases 815 , 816 , 817 . . . 819 , the Glide Solver 410 and/or Request Manager 812 may request other information from the Glide Servers 110 , 170 , onboard memory or infrastructure servers. [0087] Infrastructure servers and their databases may provide the information related but not limited to current traffic conditions, traffic light timing, current throughput, current throughput goals, current lane throughput, current lane throughput goals, traffic accidents, accident avoidance instructions, and emergency vehicle avoidance instructions. [0088] The Request Manager 812 may request data points from all necessary constraint data bases 815 , 816 , 817 . . . 819 and other data sources for all points along the request route. The Request Manager 812 may request data in parallel from all or some of the necessary constraint databases 815 , 816 , 817 . . . 819 and other data sources, or the Request Manager 812 may queue the data requests. If the Request Manager 812 queues the data requests, only one constraint database 815 , 816 , 817 . . . 819 may be queried at a time. [0089] Other Glide enabled vehicles 131 , 132 . . . 139 , 140 may also be a source of additional information that the Request Manager 812 may request data from. [0090] In step 514 in FIG. 5 , the constraint data collected by the Request Manager 812 from the constraint databases 815 , 816 , 817 . . . 819 and other data sources may be sent to the Glide Solver 410 . The Request Manager 812 may also send the route information, parameters and preferences that it received from the Requesting Device 811 a , 811 b to the Glide Solver 410 . [0091] The Glide Solver 410 may receive all of the data pertaining to the route from the Request Manager 812 at once (in bulk), or the Glide Solver 410 may receive all of the data from the Request Manager 812 in a stream as the Request Manager 812 requests the data from the constraint databases 815 , 816 , 817 . . . 819 . [0092] In step 515 in FIG. 5 , the Glide Solver 410 may use the data it received in step 514 from the Request Manager 812 to calculate the coefficient matrices of the constraints. [0093] In step 516 in FIG. 5 , the Glide Solver 410 may use the coefficient matrices constructed in step 515 to minimize the acceleration vector. The Glide Solver 410 may be an inequality constrained norm-2 solver that uses the coefficients calculated in step 515 to minimize the norm-2 of the acceleration for each point along the route. [0094] The norm-2 solver referenced above is depicted in FIG. 4 . With reference to FIG. 4 , the Glide Solver 410 , may include multiple algorithm blocks 420 , 430 . One of these blocks may be an Route optimizer 420 . This Route optimizer 420 may be the norm-2 solver referenced above. The acceleration vector that is being minimized is proportional to the energy vector. Minimizing the acceleration vector corresponds to minimizing the energy vector. [0095] Included as part of step 516 in FIG. 5 may be the Glide Solver 410 producing a set of acceleration points that constitute the solution to the minimized acceleration vector. [0096] In step 517 in FIG. 5 , the Glide Solver 410 may use the set of acceleration points created in step 516 to create a set of speed points along the route. This set of speeds along the route may serve as targets for the Glide Controller 410 to aim for as the vehicle progresses through the route. [0097] The target speed points along the route may be calculated via the minimized acceleration vector and any other factors that are vehicle, road or driver specific that might influence the movement of the vehicle. Two examples of factors that may be taken into account when the Glide Solver 410 creates the set of target speed points are the vehicle's drag coefficient as well as any load the vehicle might be carrying or pulling. [0098] In step 518 in FIG. 5 , the Request Manager 812 may receive the route results from the Glide Solver 410 , and the Request Manager 812 may send the Glide Solver's 410 results to the Requesting Device 811 a , 811 b . The Request Manager 812 may also send the inputs used for the Glide Solver 410 . [0099] If applicable, the Requesting Device 811 a , 811 b may display the results from the Glide Solver 410 on the Glide User Interface 143 . The Glide User Interface 143 may display information related but not limited to, estimated trip duration; estimated trip cost; estimated time spent moving versus idle or in traffic; total estimated energy consumption; and estimated refueling/recharging locations. [0100] Additionally, the User 141 may be able to view the results from the Glide Solver 410 and make changes to any of the input parameters that were previously provided. If the User 141 makes changes to the proposed route/trip, the Glide Request Manager 812 and Glide Solver 410 may recalculate the proposed route/trip with the new preferences or parameters proposed by the User 141 . The Request Manager 812 and Glide Solver 410 may return the edited results to the Requesting Device 811 a , 811 b and the Glide User Interface 143 . The new results may be displayed along with the previous results for the User 141 to compare. [0101] It may follow that the User 141 could input a range of route/trip parameters and preferences and the Request Manager 812 and Glide Solver 410 may return multiple different routes for the User 141 to pick from. In this way, the User 141 may be able to see how different parameters affect the results of the trip optimization. [0102] The flow diagram in FIG. 5 should not serve as an exclusive method for the Glide System 100 to complete a route request and optimization. FIG. 5 merely serves as an example for one possible way for the Glide System 100 to fulfill a route request. [0103] FIG. 6 shows a flow diagram for another possible mode of operation for the Glide System 100 . In FIG. 5 , the flow diagram depicted the possible steps the Glide System 100 may take when given route parameters. These route parameters may include starting, ending, and waypoint destinations. The flow diagram in FIG. 6 shows possible steps for the Glide System 100 operating without and final destination. [0104] In another mode, the User 141 may simply enable the Glide Controller 144 in a Glide enabled device 131 , 132 . . . 139 , 140 , 150 . In doing this, the Glide Controller 144 may look ahead for the next x-miles along the current route and optimize the route for the next x-miles. This is a functionally different mode from the previous example in that the end point is continuously moving. The Glide Controller 144 may continuously look ahead for the next x-miles, so the Glide Controller 144 is constantly updating its “end” destination. [0105] In step 611 in FIG. 6 , the Requesting Device 811 a , 811 b may enable the Glide Controller 144 . The Requesting Device 811 a , 811 b may be any of a plethora of possible devices. In the simplest realization, the Requesting Device 811 b may be a User 141 . The User 141 may enable the Glide Controller 144 via the Glide User Interface 143 . [0106] The Glide User Interface 143 may refer generally to a module capable of providing the User 141 a way to enable the Glide Controller 144 . In other modes of operation, the Glide User Interface 143 may refer generally to a module capable of providing the User 141 a way to provide route information and parameters into the Glide Controller 144 . More specifically, for all modes of operation, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data to and from the Glide Controller 144 . [0107] The Glide User Interface 143 may be a user's 141 cellular device, tablet or laptop computer. The Glide User Interface 143 may not necessarily be installed in the Glide enabled device 140 , but may be a device that is connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 , the Glide enabled device 140 , or the Glide WAN 120 . In this way, the Glide Controller 144 may be controlled remotely (outside of the Glide enabled device 140 ). This Glide User Interface 143 may be any device capable of accepting information from a User 141 . The Glide Use Interface 143 may include cellular phones, tablets, laptop computers or any other module capable of accepting inputs and communicating those inputs to the Request Manager 812 . [0108] In other realizations, the Requesting Device 811 a , 811 b may be a device similar to that of the Glide User Interface 143 . A User's 141 cellular phone, table, or laptop may be more than just the Glide User Interface 143 . The requesting Device 811 b may not necessarily be installed in the Glide enabled device 131 , 132 . . . 139 , 140 , 150 , or it may not be integrated into the Glide Controller 144 . The Requesting Device 811 a , 811 b may be connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 or directly to the Request Manager 812 . [0109] In other realizations or embodiments, the Requesting Device 811 a , 811 b may be the traffic infrastructure 150 , or the Glide Servers 110 . [0110] Referring back to FIG. 6 , step 611 , the Requesting Device 811 a , 811 b (discussed above) may enabled the Glide Controller 144 . In the connected embodiment, this may enabled the Glide Service 100 as well. [0111] The User 141 may be able to use a quick select menu to choose parameters that the Glide Controller 144 and Glide Solver 410 should optimize for. An example of this could be: the User 141 enables the Glide Controller 144 and uses the quick select menu on the Glide User Interface 143 to tell the Glide Controller 144 to optimize for time. The Glide Controller 144 may then continuously optimize the next x-miles ahead of the current position for time. [0112] In step 612 in FIG. 6 , the Request Manager 812 may insert points along the route for the next x-miles in order to create the granularity necessary to accurately optimize the next x-miles along the current route. The purpose of this step is to create more data points for the Glide Solver 410 to calculate. More data points along the route means the Glide Solver 410 will be able to solve for more acceleration points, and this means the speed targets will have finer resolution. [0113] Step 612 in FIG. 6 should not be limited to just the Request Manager 812 . In some embodiments of the Glide System 100 , the data insertion may be carried out by another functional block (e.g. the Glide Solver 410 ). [0114] In step 513 in FIG. 6 , the Request Manager 812 may fetch the necessary data from the constraint databases 815 , 816 , 817 . . . 819 . The constraint databases 815 , 816 , 817 . . . 819 may include information related to but not limited by, elevation, road speed, and road curvature. The Request Manager 812 may request data from the constraint databases 815 , 816 , 817 . . . 819 for each point along the requested route. These points may be the points created in step 512 , or they may be points provided by the Requesting Device 811 a , 811 b. [0115] The constraint databases 815 , 816 , 817 . . . 819 may be stored on the Glide Servers 110 , locally on the Glide Controller 144 , or in other locations accessible via the Glide System WAN 120 . Additionally, it may be possible to import constraint databases 815 , 816 , 817 . . . 819 into the Glide Controller 144 . The constraint data may also be read in from a media storage device that is connected to the local Glide Controller 144 . [0116] In addition to the constraint databases 815 , 816 , 817 . . . 819 , the Glide Solver 410 and/or Request Manager 812 may request other information from the Glide Servers 110 , 170 , onboard memory or infrastructure servers. [0117] Infrastructure servers and their databases may provide the information related but not limited to current traffic conditions, traffic light timing, current throughput, current throughput goals, current lane throughput, current lane throughput goals, traffic accidents, accident avoidance instructions, and emergency vehicle avoidance instructions. [0118] The Request Manager 812 may request data points from all necessary constraint data bases 815 , 816 , 817 . . . 819 and other data sources for all points along the request route. The Request Manager 812 may request data in parallel from all or some of the necessary constraint databases 815 , 816 , 817 . . . 819 and other data sources, or the Request Manager 812 may queue the data requests. If the Request Manager 812 queues the data requests, only one constraint database 815 , 816 , 817 . . . 819 may be queried at a time. [0119] Other Glide enabled vehicles 131 , 132 . . . 139 , 140 may also be a source of additional information that the Request Manager 812 may request data from. [0120] In step 514 in FIG. 6 , the constraint data collected by the Request Manager 812 from the constraint databases 815 , 816 , 817 . . . 819 and other data sources may be sent to the Glide Solver 410 . The Request Manager 812 may also send the route information, parameters and preferences that it received from the Requesting Device 811 a , 811 b to the Glide Solver 410 . [0121] The Glide Solver 410 may receive all of the data pertaining to the route from the Request Manager 812 at once (in bulk), or the Glide Solver 410 may receive all of the data from the Request Manager 812 in a stream as the Request Manager 812 requests the data from the constraint databases 815 , 816 , 817 . . . 819 . [0122] In step 515 in FIG. 6 , the Glide Solver 410 may use the data it received in step 514 from the Request Manager 812 to calculate the coefficient matrices of the constraints. [0123] In step 516 in FIG. 6 , the Glide Solver 410 may use the coefficient matrices constructed in step 515 to minimize the acceleration vector. The Glide Solver 410 may be an inequality constrained norm-2 solver that uses the coefficients calculated in step 515 to minimize the norm-2 of the acceleration for each point along the route for the next x-miles along the current route. [0124] The norm-2 solver referenced above is depicted in FIG. 4 . With reference to FIG. 4 , the Glide Solver 410 , may include multiple algorithm blocks 420 , 430 . One of these blocks may be an Route optimizer 420 . This Route optimizer 420 may be the norm-2 solver referenced above. The acceleration vector that is being minimized is proportional to the energy vector. Minimizing the acceleration vector corresponds to minimizing the energy vector. [0125] Included as part of step 516 in FIG. 6 may be the Glide Solver 410 producing a set of acceleration points that constitute the solution to the minimized acceleration vector. [0126] In step 517 in FIG. 6 , the Glide Solver 410 may use the set of acceleration points created in step 516 to create a set of speed points along the route for the next x-miles along the current route. This set of speeds along the route may serve as targets for the Glide Controller 410 to aim for as the vehicle progresses through the next x-miles of the route. [0127] The target speed points along the route for the next x-miles may be calculated via the minimized acceleration vector and any other factors that are vehicle, road or driver specific that might influence the movement of the vehicle. Two examples of factors that may be taken into account when the Glide Solver 410 creates the set of target speed points are the vehicle's drag coefficient as well as any load the vehicle might be carrying or pulling. [0128] In step 518 in FIG. 6 , the Request Manager 812 may receive the route results from the Glide Solver 410 , and the Request Manager 812 may send the Glide Solver's 410 results to the Requesting Device 811 a , 811 b . The Request Manager 812 may also send the inputs used for the Glide Solver 410 . [0129] It should be noted that the Glide Solver 410 may provide multiple different routes for the same starting and ending destinations. These multiple different routes may be displayed to the User 141 , and the User 141 may be able to choose the preferred route. In addition to providing multiple routes, the Glide Solver 410 may provide estimations for time of arrival, energy usage, and necessary refueling or recharging. The estimations or additional information provided by the Glide Solver 410 should not be limited to the above listed data. [0130] In other embodiments, third party routing services may be used to provide the multiple different routes. In this embodiment, the Glide Solver 410 may then be applied to the multiple different routes provided by the third party routing services. [0131] If applicable, the Requesting Device 811 a , 811 b may display the results from the Glide Solver 410 on the Glide User Interface 143 . The Glide User Interface 143 may display information related but not limited to, estimated running cost since the Glide Controller 144 has been enabled; estimated and running totals of time spent moving versus idle or in traffic; total estimated energy consumption since the Glide Controller 144 has been enabled; and estimated refueling/recharging locations based on the needs of the vehicle for the next x-miles of the route. [0132] Additionally, the User 141 may be able to view the results from the Glide Solver 410 and make changes to the quick select optimization selections that were originally made. If the User 141 makes changes to the quick select optimization selections, the Glide Request Manager 812 and Glide Solver 410 may recalculate the next x-miles of the current route with the new quick select selections provided by the User 141 . The Request Manager 812 and Glide Solver 410 may return the edited results to the Requesting Device 811 a , 811 b and the Glide User Interface 143 . The new results may be displayed along with the previous results for the User 141 to compare. Ultimately, the User 141 may be asked to select from one of the possible optimizations of the next x-miles, or the Glide Controller 144 may default to a preset optimization setting for the next x-miles if one is not chosen. [0133] The flow diagram in FIG. 6 should not serve as an exclusive method for the Glide System 100 to complete a route optimization for the next x-miles of the current route. FIG. 6 merely serves as an example for one possible way for the Glide System 100 to fulfill a request to optimize the next x-miles of the current route. III. Elevatier (Elevation Finder) [0134] FIG. 4 shows a possible functional block for the Glide Controller 144 and Glide Solver 410 . The Glide Solver 410 may include specific algorithms designed to complete tasks in the Glide System 100 . The Elevatier 430 may be one of these algorithms. [0135] The Elevatier 430 may describe an algorithm specifically designed for finding a point of data (related geographically) from a very large database of information. While not limiting the scope of application for this algorithm, the Glide System 100 may use this algorithm for quickly finding data related to elevation along the requested route. The general algorithm used in the Elevatier 430 may be applied to any rapid search function tasked with querying large databases for data points. [0136] The index and indexing algorithm used by the Elevatier 430 may include any of a wide range of algorithms and indexing methods. Specifically, an rtree indexing scheme and data structure may be used to organize data. It may also follow that an rtree spatial indexing algorithm may be used by the Elevatier 430 to search a database. The spatial data structure index and the spatial indexing algorithm should not be limited to one of an rtree nature; the rtree example serves only to show one possibility for the structure and algorithm. [0137] FIG. 9 shows how elevation data may be organized to allow for the Elevatier 430 to quickly extract data need by the Glide Solver 410 . The configuration file 910 for the given data may be broken into N regions 921 . . . 929 . An example of the regional level 921 . . . 929 could be sections of the continental United States (west, central, and east). These regions may then be broken down into sub-regions 931 , 932 . . . 939 , 940 . An example of this could be states within the larger region (Washington, Oregon, California, Arizona, Nevada and Idaho could be in the west region). FIG. 9 depicts two levels of data (regions 921 . . . 929 and sub-regions 931 , 932 . . . 939 , 940 ), but data organization should not be limited to two levels. Data organization levels may extend as many levels as necessary. To continue with the above example, the next layer could be regions within each state, then counties within each region, then cities within each county. [0138] All files for a given region may be stored in the same directory, and they may be indexed spatially. This may hold true for any region 921 . . . 929 or sub-region 931 , 932 . . . 939 , 940 level in the data organization scheme. Organization may include regions 921 . . . 929 and sub-regions 931 , 932 . . . 939 , 940 being stored in the same hierarchical level. The regions 921 . . . 929 and sub-regions 931 , 932 . . . 939 , 940 may also not be hierarchical. [0139] FIG. 10A shows how data may be manipulated between the raw data 1011 stored in memory (be it local or on a server) and the data that is accessed 1013 for delivery to the Request Manager 812 and eventually the Glide Solver 410 . [0140] Before the data point(s) 1014 being requested are found in the data base 1013 , the Elevatier 430 algorithm may rasterize the raw elevation data 1012 to produce and even spaced matrix 1013 of data points 1014 . FIG. 10A shows the matrix 1011 of un-rasterized (raw) data points 1012 . The Elevatier 430 algorithm may rasterized the raw data 1012 to produce a rasterized matrix 1013 of the rasterized data points 1014 . [0141] The Request Manager 812 may request a data point that already exists in the elevation database. If this is the case, the Elevatier 430 algorithm may simply rasterize the data and select the data point 1014 from the rasterized matrix 1013 . [0142] If the Request Manager 812 requests a data point that is not already in the elevation database, the Elevatier 430 may have to extrapolate the data point from the existing points in the database. [0143] There may be a functional block, included with the Elevatier that is an elevation request manager for the Elevatier. This elevation request manager may be different from the Request Manager 812 . While the Request Manager 812 may handle data between the Elevatier 430 , constraint databases 815 , 816 , 817 . . . 819 , the Glide Solver 410 , and the Requesting Device 811 a , 811 b , the elevation request manager may be a front end function of the Elevatier 430 that may handle incoming data point requests. [0144] To obtain the extrapolated point 1015 , that the Request Manager 812 has requested, a polygon 1016 may be created around the requested point 1015 . The points that make up the polygon vertices may include the polygon vertices' locations as well as the elevation information at the polygon points. The point of interest 1015 (the queried elevation point) may then be extrapolated from the points surrounding it (the vertices of the polygon). [0145] FIG. 10A serves only to illustrate how a data point that is not already in the database may be extrapolated from surrounding data points. It should in no way serve as a limiting or exclusive situation. For example, the polygon formed by already existing, surrounding data points may be a hexagon or other polygon. [0146] In addition to querying data points, the Elevatier 430 algorithm may also add points 1023 to the existing databases. FIG. 10B shows the un-rasterized (raw) data matrix 1021 including the raw data points 1022 . FIG. 10B also shows a new data point 1023 may be added to the existing data set. In this way, the Glide System 100 may take data collected from Glide enabled devices 131 , 132 . . . 139 , 140 , 150 and increase the size and accuracy of the Glide databases with this gathered information. [0147] FIG. 7 shows a possible flow path for the Elevatier 430 algorithm. FIG. 7 should in no way serve as a limiting or exclusive flow path; its purpose is simply to illustrate how a database querying algorithm like the Elevatier 430 could work. [0148] In step 710 in FIG. 7 , an elevation point may be queried by the Request Manager 812 . This requested data point could correspond to the geographic location of one of the route points created in step 512 or 612 in FIG. 5 and FIG. 6 , respectively. [0149] In step 720 a , the Elevatier 430 algorithm may search the configuration file 910 for the region(s) 921 . . . 929 that include the queried point. [0150] To complete step 720 a , the Elevatier 430 algorithm will cycle through two nested loops. The first loop may cycle through the regions 921 . . . 929 , and the second loop may cycle through the sub-regions 931 , 932 . . . 939 , 940 . [0151] In step 720 b in FIG. 7 , the region counter may be set to 0. Step 730 a may enter the second nested loop of the Elevatier 430 algorithm. The initial condition of the second nested loop is to set the sub-region counter to 0 730 b. [0152] In step 740 in FIG. 7 , the polygon contacting the queried point in a particular region and sub-region is stored. The information stored during this step may include but is not limited to the elevation data and the accuracy associated with the elevation data. [0153] Steps 750 and 760 in FIG. 7 may serve as loop checks to allow the Elevatier 430 algorithm to decide when to exit one of the loops. The loop indexes may be positively index each loop iteration to cycle through all sub-regions 931 , 932 . . . 939 and all regions 921 . . . 929 . [0154] In step 770 in FIG. 7 , all of the elevation points stored from step 740 may be compared, and the one(s) with the highest accuracy are saved. [0155] In step 780 in FIG. 7 , the polygon 1016 surrounding the point of interest 1015 may be formed, and the single point of interest 1015 can be extrapolated from the polygon 1016 . IV. Glide Controller Variations [0156] A Glide Controller 144 may have different configurations within the Glide System 100 . Three possible variations will now be discussed. These three variations should in no way limit the variation possibilities of the Glide Controller 144 within or outside of the Glide System 100 . [0157] FIG. 8A depicts one possible variation of the Glide Controller 144 within the Glide System 100 . In FIG. 8A , the Glide Controller 144 may include multiple modules. These modules may include the Requesting Device 811 a , the Request Manager 812 and the Glide Solver 410 . In this configuration, the Glide Controller 144 is also the Requesting Device 811 a. [0158] In FIG. 8A , the Requesting Device 811 a is shown as a sub component of the Glide Controller 144 . In this way, the Glide Controller 144 may be receiving the requested route from the internal Requesting Device 811 a . An example of this situation may include the Glide Controller 144 optimizing for the next x-miles, without receiving an ending destination. [0159] In FIG. 8A , the Request Manager 812 and Glide Solver 410 are hosted locally on the Glide Controller 144 . This means that computation carried out by the Route Optimizer 420 and the Elevatier 430 may occur locally on the Glide Controller 144 . [0160] In FIG. 8A , the constraint databases 815 , 816 , 817 . . . 819 are shown as existing on the Glide Servers 110 . It would follow that in this configuration, the Glide Controller 144 would be operating in the “connected”, subscription-based mode, where a User 141 may pay a temporally regular fee for regular communication 160 with the Glide Servers 110 . [0161] FIG. 8B depicts another possible variation of the Glide Controller 144 within the Glide System 100 . In FIG. 8B , the Glide Controller may include all of the functional blocks that have been previously discussed. This would include the Requesting Device 811 a , the Request Manager 812 , the Glide Solver 410 and the constraint databases 815 , 816 , 817 . . . 819 . In this configuration, like the last, the Glide Controller 144 is also the Requesting Device 811 a. [0162] In FIG. 8B , the Requesting Device 811 a is shown as a sub component of the Glide Controller 144 . In this way, the Glide Controller 144 may be receiving the requested route from the internal Requesting Device 811 a . An example of this situation may include the Glide Controller 144 optimizing for the next x-miles, without receiving an ending destination. [0163] In FIG. 8B , the Request Manager 812 and Glide Solver 410 are hosted locally on the Glide Controller 144 . This means that computation carried out by the Route optimizer 420 and the Elevatier 430 may occur locally on the Glide Controller 144 . [0164] In FIG. 8B , the constraint databases 815 , 816 , 817 . . . 819 are shown as existing locally on the Glide Controller 144 . It would follow that in this configuration, the Glide Controller 144 would be operating in the stand-alone mode, where the Glide Controller 144 may only communicate 160 with the Glide Servers 170 to apply firmware updates and database 815 , 816 , 817 . . . 819 data updates. [0165] FIG. 8C depicts yet another possible variation of the Glide Controller 144 within the Glide System 100 . In FIG. 8C , the Glide Controller may include the function blocks previously discussed, the Request Manager 812 , and the Glide Solver 410 , but may not be the Requesting Device 811 b. [0166] In the FIG. 8C variation, the Requesting Device 811 a may be a module in the Glide Controller 144 (similar to FIG. 8A , FIG. 8B ), or the Requesting Device 811 b may be a User accessing the Glide System 100 via the Glide User Interface 143 , or the Requesting Device 811 b may be a device similar to that of the Glide User Interface 143 (discussed in earlier sections). A User's 141 cellular phone, tablet, or laptop may be used as the Requesting Device 811 b . The Requesting Device 811 b may not necessarily be installed in the Glide enabled device 131 , 132 . . . 139 , 140 , 150 , or it may not be integrated into the Glide Controller 144 . The Requesting Device 811 b may be connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 or directly to the Request Manager 812 . [0167] FIG. 8A-8C should not serve as limiting or exclusive examples of variations to the Glide Controller. Other examples could include a variation where the Glide Servers 110 hold all of the functional blocks including the Request Manager 812 , the Glide Controller 410 , and the constraint databases 815 , 816 , 817 . . . 819 . In this variation, the computation carried about by the Glide Solver 410 would be carried out on the Glide Servers 110 , and the results would be sent back to the Glide Controller 144 , which may serve simply as a Glide WAN 120 terminal for the Glide User Interface 143 in a Glide enabled device 131 , 132 . . . 139 , 140 , 150 . [0168] It should be noted that the variations discussed above are not mutually exclusive. For one route optimization, the variation shown in FIG. 8A may hold, where the Glide Controller 144 is also the Requesting Device 811 a (e.g., the User 141 enables the Glide Controller 144 to optimize for the next x-miles along the current route). That same Glide Controller 144 for its next route optimization task may assume the variation shown in FIG. 8C where the Requesting Device 811 b is the User's 141 cellular device that is requesting a route optimization from the Glide Controller 144 and the Glide System 100 . V. Operational Modes and Communications [0169] The different modes of operation for the Glide System 100 will now be expanded on. The Glide System 100 may have multiple different modes that a Glide Controller 144 may operate in, and any Glide Controller 144 may operate in multiple different modes at once. These are different from the Glide Controller 144 variations discussed in the previous section. [0170] In the connected, subscription-based mode, a Glide Controller 144 may communicate via the Glide WAN 120 with the Glide Servers 110 to obtain the information necessary for the Glide Solver 410 to optimize the request route for the desired parameters. In this mode, the Glide Solver 410 may use available data; vehicle models; traffic models and vehicle State of Charge models (for hybrid or electric vehicles) to calculate acceleration points; speed targets, optimal lanes when to apply a certain power train (internal combustion versus electric versus both); when to apply regenerative deceleration; and which gears to use for maximum efficiency. This is an example of parameters and solutions the Glide Solver 410 may use and carry out; it should by no means serve as an exclusive list for what the Glide Solver 410 and Glide System 100 may do. [0171] In the stand-alone application, the Glide Controller 144 in the Glide enabled device 131 , 132 . . . 139 , 140 , 150 may not communicate 160 with the Glide Servers 110 , but may rather solve the route optimization using data included locally on the Glide Controller 144 . In this way, the Glide Controller 144 would not receiver data from the Glide Servers 110 that is pertinent to solving the route optimization. This stand-alone configuration may allow for a Glide Controller 144 to download firmware updates from the Glide Servers 170 . These firmware updates may include firmware that runs on a Glide Controller 144 as well as updates to the data stored locally on the Glide Controller 144 that the controller uses to solve the route optimization. This model may be compared to a GPS unit where the unit periodically downloads updates, but it relies on internal data for functionality. [0172] Both the subscription-based mode and the stand-alone mode may be able to carry out the same functionality in terms of route optimization. [0173] Both the subscription-based mode and stand-alone modes may be used with final destinations or simply with the Glide Controller 410 enabled to optimize the next x-miles on the current route. [0174] With infrastructure to vehicle communication 160 , a Glide Controller 144 may be operating on the traffic infrastructure 150 side of the Glide System 100 as well as in a Glide enabled vehicle 131 , 132 . . . 139 , 140 . The infrastructure may solve for parameters including but not limited to vehicle speeds; optimal lanes for traffic flow and throughput; speed smoothing and vehicle spacing; occupancy or vehicle type by lanes; traffic light sequencing based on flow patterns; and traffic behavior alteration for crashes and emergency vehicles. A Glide Controller 144 operating on the traffic infrastructure 150 may send instructions to alter driving behavior to Glide Controllers 144 operating in Glide enabled vehicles 131 , 132 . . . 139 , 140 . [0175] With this communication 160 from the transportation infrastructure to the vehicle, the Glide System 100 may be able to instruct vehicles to switch lanes or slow down to increase or meet a desired throughput of a particular area along a route. Additionally, the traffic infrastructure may be able to send instructions that will allow lane clearing for an accident ahead of a Glide enabled vehicle's 131 , 132 . . . 139 , 140 current location or for an emergency/special vehicle approaching a Glide enable vehicle's 131 , 132 . . . 139 , 140 location. [0176] The infrastructure to vehicle communication 160 may also allow the traffic infrastructure to speed smooth traffic in real-time or space vehicles for optimal travel efficiency. [0177] In vehicle to vehicle communication (Symbiotic Vehicular Synchronizer), one Glide Controller 144 may send notifications about upcoming events to other Glide enabled vehicles 131 , 132 . . . 139 , 140 behind and around it. These notifications may be used by the receiving Glide Controllers 144 to adjust the optimized route in real time. [0178] Vehicle to vehicle communication allows the optimized route to be a fluid solution that adjusts for real time data. This differs from current solutions that may require all information to be routed through system servers before clients may use the information. In allowing for real-time vehicle to vehicle communication, the Glide System may be proactive about route decisions based on information close in time and proximity to a Glide enabled vehicle 131 , 132 . . . 139 , 140 . [0179] Vehicle to vehicle communication may also occur via the Glide Servers. In this communication embodiment, a Glide enabled vehicle 131 , 132 . . . 139 , 140 may communication information to the Glide Servers 110 , 170 , which may then communicate necessary information to other Glide enabled vehicles 131 , 132 . . . 139 , 140 . The communication 160 to and from the Glide Servers 110 , 170 and the Glide enabled vehicles 131 , 132 . . . 139 , 140 may occur via the Glide WAN 120 . In this way, the Glide System 100 may build fluid constraint databases that respond to changing environments. [0180] Information shared by the Symbiotic Vehicular Synchronizer may include but is not limited to, traction failure of preceding vehicles (slippery section of a lane); traffic for the next y-miles along the current route or routes close in proximity to the current location of the vehicle; vertical motion and disturbances (bumps and potholes); breakdowns and accidents, for route and lane avoidance; Glide enabled vehicle locations for convoy opportunities and enhanced diving. [0181] It should be noted that all modes of operation for the Glide System may use the vehicular sensor suite that may be integrated into the vehicle. VI. Modifications and Enhancements [0182] As with any system involved with a complex task, there are always additions that can be made. The following serves as a short list of selected features that the Glide System 100 may employ to increase the completeness of the system. [0183] The Glide System 100 and Glide Controller 144 may include the ability to provide supplemental information regarding the requested or optimized route. This may include functionality to plan out rest stops where the route plan may include when and where to refuel/recharge; which power plant to refuel/recharge (in a hybrid topology); and rest stops and food options. The Glide System 100 and Glide Controller 144 may provide supplemental information including but not limited to, rest-stop information, food services information, refueling and/or recharging information, and lodging information. [0184] The ability of the Glide System 100 to provide recommendations on where to refuel and which power plant to replenish (in a hybrid topology) may be a necessary add-on for hypermiling. The variation in gasoline prices coupled with the sporadic placement of charging stations means there is a large amount of variation in the refueling/recharging plan for a route, especially a lengthy route. [0185] The Glide System 100 may be able to compare gasoline prices for the next z-miles along the route with the availability of charge stations and their costs. This refueling station analysis may then be compared to the length of the route and the current state of the power plant sources (gasoline level and battery charge level). The Glide Controller 144 may then make a decision on the most optimal place to refuel at, given the route preferences. This analysis may change the way the Glide Solver 410 calculates the acceleration schedule for the vehicle [0186] An example of route manipulation due to refueling options could be the following. If the Glide System 100 determines the next gasoline station prices to be expensive relative to another much closer to the final destination, the Glide Controller 144 may choose to have the Glide Solver 410 re-optimize the route, but this time the Glide Solver 410 may be instructed to weight the power plant usage towards a heavier usage of the electric powertrain. In this way, the Glide Controller 144 will save fuel in anticipation of bypassing the more expensive refueling station in favor of the refueling station close to the final destination. [0187] The Glide System 100 may include the ability to optimize for holistic cost versus time balancing which may include HOV/Toll lanes and casual carpool pickups and drop-offs. This could also include a time flexibility parameter for situations like urgent meetings, concerts or other time sensitive activities. [0188] The Glide System 100 may include the ability to estimate and adjust for trailering and other vehicle alterations that may be outside of the standard vehicle models. The Glide System 100 may also include the ability to adjust for weather considerations: snow, rain wind, etc. This may include the consideration of snow-chains or whether or not the vehicle is all-wheel-drive equipped and if a route requires that or not. VII. Glide User Interface [0189] The above discussions have included references to a Glide User Interface 143 . This interface may be embodied in any number of different ways. In a general sense, the Glide User Interface 143 may refer to a module capable of providing the User 141 a way to import route information into the Glide Controller 144 . More specifically, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data. [0190] The screen depictions discussed here should not serve as limiting or exclusive matter, but rather they should serve as examples to aid in the explanation of how the Glide User Interface 143 may function and show data. [0191] FIG. 11 depicts a possible screen that a User 141 could be shown while interfacing with the Glide User Interface 143 . 1100 may be generally referred to as the home screen. This is the screen that the User 141 may be returned to, upon requesting so, during operation of the Glide User Interface 143 . [0192] FIG. 11 depicts a possible home screen 1100 with multiple choices for the User 141 . If the User 141 does not want to input a final destination, the User 141 may select choice 1110 , which may request that the Glide System 100 operate without an end destination and rather optimize for the next x-miles. The User 141 may selection choice 1120 which may send the User 141 to a screen FIG. 12 that may prompt the User 141 for more information about the new route 1200 . [0193] FIG. 11 may also have a My Routes selection 1130 that when selected may show the User 141 the previous routes the User 141 has selected as well as routes or destinations the User 141 has saved in an Address Book. The Address Book may hold destinations as well as save routes. An example of this could include the Address Book holding the simple address of the User's 141 office building and holding the saved route to the office building with the route preferences that the User 141 usually selects for the route to the office building. [0194] FIG. 11 may also present the User 141 with a Connect Device selection 1150 , which when selected, may allow the User 141 to connect an eligible device to the Glide Controller 144 . The User 141 may be presented with a System Settings 1150 selection, where the settings for the Glide User Interface 143 and the Glide Controller 144 may be altered. The User 141 may also be presented with a My Glide selection 1160 , which may allow the User 141 to view and their Glide Profile. [0195] FIG. 11 may also present the User 141 with a Map selection 1170 which, when selected, may take the User 141 to a map view that may show the location and current statics of the vehicle. This may not necessarily enabled the Glide System 100 . [0196] FIG. 12 was referenced above when discussing new route information. FIG. 12 depicts a possible screen that may generally be referred to as the New Route Selection screen 1200 . The New Route Selection 1200 may include multiple ways and selections for the User 141 to fill in with regards to the new route. The New Route Selection 1200 may prompt the User 141 with a field 1210 to input the street address of the destination. When 1210 is selected, an on screen keyboard may present itself to aid the User 141 in inputting data. Additionally, the street address 1210 may be taken in using voice commands or the native driver interface that is installed in the vehicle. [0197] The New Route Selection 1200 may present the User 141 with options to access previously stored addresses, trips, and points of interest (POIs) 1220 , 1260 , 1270 . [0198] Selection 1220 in FIG. 12 may allow the User 141 to access previously stored address. After selecting an address from the Address Book, the User 141 may be returned to the New Route Selection screen 1200 to input the preferred optimization for the New Route. [0199] Selection 1260 in FIG. 12 may allow the User 141 to access previously completed or stored trips. After selecting a previously stored trip, the User 141 may be returned to the New Route Selection screen 1200 to input the preferred optimization for the new route. It may also be possible that the previously stored trip selection may include the optimization and route preferences from that trip. These preferences may already be selected or highlighted when the User 141 is returned to the New Route Selection screen 1220 . [0200] Selection 1270 in FIG. 12 may allow the User 141 to access a database of points of interest. After selecting a point of interest, the User 141 may be returned to the New Route Selection screen 1200 to input the preferred optimization for the New Route. [0201] FIG. 12 may also present the User 141 with route optimization selections 1230 a , 1230 b , 1230 c , 1230 d . These choices may include but are not limited to energy 1230 a , time 1230 b , cost 1230 c , and traffic 1230 d . The User 141 may be able to choose any number of optimization strategies for the new route. It may be that the first strategy selected will be the highest priority, and the last strategy selected will be the lowest priority. [0202] FIG. 12 may also present the User 141 with a Route selection 1240 , which when selected may send the selected information from the above discussion to the Glide System as a Requested Route. [0203] FIG. 12 the New Route Selection screen 1200 may also have selections for the Map screen 1170 and the home screen 1250 . The Map selection 1170 which, when selected, may take the User 141 to a map view that may show the location and current statics of the vehicle. This may not necessarily enabled the Glide System 100 . The home selection 1250 , when selected, may return the User 141 to the home screen 1100 . [0204] FIG. 13 shows a possible depiction of the guidance screen for the Glide User Interface 143 . 1300 may be generally referred to as the Guidance Screen. The Guidance Screen 1300 may include information about the vehicle and the current route. [0205] The Guidance Screen 1300 may display the current 1310 and target 1320 speeds for the vehicle. The target speed 1320 may represent the spatially next data point calculated by the Glide Solver 410 along the route. [0206] The Guidance Screen 1300 may display the systems calculated estimated time of arrival to the destination (if applicable). If the Glide System 100 is operating without a final destination, this piece of information may not be displayed. [0207] The Guidance Screen 1300 may display current efficiency of the trip, normalized against similar trips or a best estimated trip that doesn't use the Glide System 100 . The Guidance Screen 1300 may also have a Stats selection 1350 that may take the User 141 to another screen that displays more in depth stats for the trip. [0208] The Guidance Screen 1300 may also display information to alter the driver to the next driving operation that should be carried out as part of the trip plan. The map area 1360 of the Guidance Screen 1300 may display any number of different types of maps (multiple at one time or a single map at a time). [0209] In addition to a map 1360 , the Guidance Screen 1300 may display a Next Step section 1370 for the route. As shown in FIG. 13 this may include written instructions for the next step as well as a visual representation. Additionally, the Glide System may give an auditory message of the next step. [0210] The information the Guidance Screen 1300 displays should not be limited to the above discussion. Other information including battery state of charge, distance to next refueling station, and surrounding vehicles using the Glide System may also be displayed on the Guidance Screen 1300 . VIII. Glide Application and Web Service [0211] The Glide User Interface 143 installed in a Glide enabled device 131 , 132 . . . 139 , 140 , 150 may not be the only device capable of displaying Glide System information. As discussed above, there may be many devices capable of acting as a Glide User Interface 143 that is not necessary installed in a Glide enabled device 131 , 132 . . . 139 , 140 , 150 . [0212] Interaction between the User 141 and a Glide User Interface 143 may occur via a Glide Application or a Glide Web Service. The Glide Application or Web Service may run generally, on a computing device, and specifically, on a device with tactile or virtual buttons capable of receiving input and a method for reading information out to an operator. Devices may include but are not limited to, cellular telephones, tablet computers, laptop computers, desktop computers, and other variations of these devices. [0213] The Glide Application or Web Service may have the same functionality as the Glide User Interface described in the previous section. The Glide Application or Web Service may have a home screen 1100 similar to the one shown in FIG. 11 . It may be possible for the Glide Application or Web Service to take in route information from an operator using a screen similar to the New Route Selection screen 1200 shown in FIG. 12 . The Glide Application or Web Service may then store or send this information to a Glide Controller 144 . Additionally, the Glide Application or Web Service may be able to display real-time information pertaining to an in progress route using a screen similar to the Guidance Screen 1300 shown in FIG. 13 . [0214] The Glide Application or Web Service may connect to the Glide Servers 110 , 170 and directly to a Glide Controller 144 . The device running the Glide Application or Web Service may communicate with the Glide Servers 110 , 170 using any number of communication methods including but not limited to, 3G, 4G, or 5G cellular communication; or WiFi. The device running the Glide Application or Web Service may communicate with the Glide Controller 144 using any number of communication methods including but not limited to, 3G, 4G, or 5G cellular communication; WiFi, DSRC, Bluetooth, or ZigBee. IX. Glide Profile [0215] The Glide System 100 may allow Users 141 to create profiles that may be saved on the Glide Servers 110 , 170 . These profiles may include saved information pertaining to a particular User 141 or driver, or the profiles may include saved information pertaining to a particular vehicle. All types of Glide Profiles may save information pertaining to previous trips, saved addresses, saved settings/preferences, and accumulated statistics. Glide Profiles for either a User 141 or a Glide enabled device 131 , 132 . . . 139 , 140 should not be limited in scope by the current discussion. [0216] A User 141 may be able to access a particular Glide Profile from any number of Glide Controllers 144 . This may allow a User 141 to access a particular Glide Profile from a Glide Controller 144 or Glide User Interface 143 that may not necessarily be installed in a Glide enabled device 131 , 132 . . . 139 , 140 owned by the User 141 . [0217] Two examples of accessing a Glide Profile that may not be owned by the primary account holder may include using the Glide System 100 in a Glide enabled rental car, or using the Glide System 100 in a friend's Glide enabled vehicle. Continuing with the rental car example; a User 141 may be able to access saved routes, saved addresses, saved preferences, and saved statistics via their Glide Profile so that they may use the full extent of the Glide System 100 , while driving a Glide enabled rental vehicle. [0218] It may be possible for a User 141 to temporarily transfer paid Glide services to another Glide Controller 144 . An example of this may include, the rental car company pays only for the stand-alone Glide service, but the current User 141 (renter of the car) pays for the subscription based model with constant access to the Glide Servers 110 . In this example, the Glide Controller 144 in the rental car may be able to access the Glide Servers 110 , while the User's 141 Glide Profile is active on the Glide Controller 144 in the rental vehicle. [0219] It may be possible to access a Glide Profile from devices other than a Glide User Interface 143 . As discussed in the previous section, a Glide Application running on a computing device, may have the capabilities to access the Glide Servers 110 , 170 , to add and retrieve Glide Profile information. In this way, it may be possible for a User 141 to access a Glide Profile from a cellular device to input a destination or route parameters, save the destination or route parameters, and then access this data from a Glide User Interface 143 in a Glide enabled device 131 , 132 . . . 139 , 140 . [0220] In sum, the present invention provides a system and methods for optimizing a vehicle's route and Glide schedule using information related but not limited to traffic, time, cost, weather, vehicular sensor data, and refueling/recharging. The advantages of such a system include the ability to optimize and adjust a travel route based on a limitless number of parameters and inputs that would otherwise not be possible especially if these parameters and inputs were beyond the line of sight of the vehicle's operator. [0221] While this invention has been described in terms of several embodiments, there are alterations, modifications, permutations, and substitute equivalents, which fall within the scope of this invention. Although sub-section titles have been provided to aid in the description of the invention, these titles are merely illustrative and are not intended to limit the scope of the present invention. [0222] It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, modifications, permutations, and substitute equivalents as fall within the true spirit and scope of the present invention.
A vehicular glide solver receives a requested route defined by at least one route parameter. The solver optimizes the requested route using vehicular optimization criteria. The optimization includes analysis of at least one data set pertaining to the requested route, and provides a vehicular glide schedule for discrete points along the requested route in response to the route optimization. The solver dynamically adjusts the vehicular glide schedule in response to a change in one of the at least one data set.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority from U.S. Provisional Application No. 62/162,215 filed on May 15, 2015, entitled “Route Based Vehicle Speed Optimization for Fuel Efficiency”, which is hereby fully incorporated by reference.", "This application also claims priority from U.S. Provisional Application No. 62/162,258 filed on May 15, 2015, entitled “Route Aware Speed Control for Fuel Efficiency”, which is hereby fully incorporated by reference.", "This application further claims priority from U.S. Provisional Application No. 62/162,287 filed on May 15, 2015, entitled “Elevation Querying System”, which is hereby fully incorporated by reference.", "[0002] Further, this application is related to co-pending U.S. application Ser.", "No. ______, (Attorney Docket Number MGL-1602-US) filed May 11, 2016, entitled “Elevation Query Systems for Vehicular Route Optimization and Methods thereof”, which is hereby fully incorporated by reference.", "[0003] Additionally, this application is related to co-pending U.S. application Ser.", "No. ______, (Attorney Docket Number MGL-1603-US) filed May 11, 2016, entitled “System and Methods for Efficient Resource Management During Vehicular Journeys”, which is hereby fully incorporated by reference.", "BACKGROUND [0004] The present invention relates to systems and methods for efficiently deploying valuable resources, such as cost and duration, especially during extended vehicular trips.", "[0005] While many vehicles available today offer conveniences such as cruise control, they provide few options for assisting drivers interested in dynamically optimizing fuel efficiency.", "For example, cruise control works reasonably well for maintaining a constant speed on a straight and flat interstate freeway with moderate traffic.", "In newer and better equipped vehicles, adaptive cruise control enables these drivers to maintain appropriately safe spacing between vehicles when the vehicle ahead changes speed, while lane departure warning system alerts inattentive drivers who drift from their intended lane of traffic.", "However, the general goal of the current vehicular control systems is to minimize driver workload and/or to enhance driver safety.", "[0006] Some driver-agnostic and route-agnostic attempts at reducing fuel consumption do exist, and they include “one-size-fits-all”", "strategies such as capping the rate of acceleration or shifting gears at more efficient preset speeds, often marketed as “ECO”", "driving mode.", "However these “ECO”", "modes substantially compromise vehicular performance, and also ignore individual driver preferences and actual routes driven, thereby adversely impacts drivers'", "overall experience.", "[0007] It is therefore apparent that an urgent need exists for systems and methods targeted at increasing efficiency of vehicles while dynamically taking into consideration real-time route characteristics.", "With the average cost of new cars in the United States now exceeding $30,000, existing vehicles are expected to remain in service for ten or more years.", "Hence, in addition to improving the dynamic efficiency of new vehicles, such improved systems and methods enable a large number of existing vehicles to be retrofitted and transformed into dynamically efficient vehicles.", "SUMMARY [0008] To achieve the foregoing and in accordance with the present invention, systems and methods for dynamically and efficiently operating a vehicle along a route in real-time is provided.", "[0009] In one embodiment, a vehicular glide solver receives a requested route defined by at least one route parameter.", "The solver optimizes the requested route using vehicular optimization criteria, wherein the optimization includes analysis of at least one data set pertaining to the requested route, and provides a vehicular glide schedule for discrete points along the requested route in response to the route optimization.", "The solver dynamically adjusts the vehicular glide schedule in response to a change in one of the at least one data set.", "[0010] Note that the various features of the present invention described above may be practiced alone or in combination.", "These and other features of the present invention will be described in more detail below in the detailed description of the invention and in conjunction with the following figures.", "BRIEF DESCRIPTION OF THE DRAWINGS [0011] In order that the present invention may be more clearly ascertained, some embodiments will now be described, by way of example, with reference to the accompanying drawings, in which: [0012] FIGS. 1-4 are block diagrams illustrating one embodiment of a dynamic vehicular resource optimization system in accordance with the present invention;", "[0013] FIGS. 5-7 are flowcharts illustrating the embodiment of the dynamic vehicular resource optimization system of FIGS. 1-4 ;", "[0014] FIGS. 8A-8C are block diagrams illustrating three alternative implementations of a glide controller for the dynamic vehicular resource optimization system of FIGS. 1-4 ;", "[0015] FIGS. 9 and 10A-10B illustrate one embodiment of an elevatier for the dynamic vehicular resource optimization system of FIGS. 1-4 ;", "and [0016] FIGS. 11-13 are screenshots illustrating the embodiment of the dynamic vehicular resource optimization system of FIGS. 1-4 .", "DETAILED DESCRIPTION [0017] The present invention will now be described in detail with reference to several embodiments thereof as illustrated in the accompanying drawings.", "In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the present invention.", "It will be apparent, however, to one skilled in the art, that embodiments may be practiced without some or all of these specific details.", "In other instances, well known process steps and/or structures have not been described in detail in order to not unnecessarily obscure the present invention.", "The features and advantages of embodiments may be better understood with reference to the drawings and discussions that follow.", "[0018] Aspects, features and advantages of exemplary embodiments of the present invention will become better understood with regard to the following description in connection with the accompanying drawing(s).", "It should be apparent to those skilled in the art that the described embodiments of the present invention provided herein are illustrative only and not limiting, having been presented by way of example only.", "All features disclosed in this description may be replaced by alternative features serving the same or similar purpose, unless expressly stated otherwise.", "Therefore, numerous other embodiments of the modifications thereof are contemplated as falling within the scope of the present invention as defined herein and equivalents thereto.", "Hence, use of absolute and/or sequential terms, such as, for example, “always,” “will,” “will not,” “shall,” “shall not,” “must,” “must not,” “first,” “initially,” “next,” “subsequently,” “before,” “after,” “lastly,” and “finally,” are not meant to limit the scope of the present invention as the embodiments disclosed herein are merely exemplary.", "[0019] The present invention relates to systems and methods for optimizing a vehicle's route and Glide schedule using information related but not limited to traffic, time, cost, weather, vehicular sensor data, cost, and refueling/recharging.", "In particular, the present invention is directed to the novel methods and systems to optimize the route of a transportation vehicle based on optimization preferences, and provide the vehicle user and the vehicle with an optimized route based on the optimization preferences.", "Additionally, the present invention is directed to the novel methods and systems that enable a user to temporarily relinquish acceleration and braking (regenerative deceleration, engine braking, and friction braking) to the present invention for the purpose of increasing a vehicle's efficiency and optimizing one or more of a vehicle route's parameters (e.g. time, cost);", "this could be thought of as an advanced or “smart”", "cruise control.", "Additionally, the present invention is directed to the novel methods and systems that enable a transportation infrastructure (namely vehicular) to optimize one of many parameters, including but not limited to, traffic flow, total throughput, and lane avoidance/clearance, by providing vehicles with instructions directed at how to manipulate driving behaviors.", "[0020] The following discussion serves to explain the methods and systems of the present invention.", "There are multiple examples throughout the discussion that aid in the explanation of certain features or methods the present invention has or uses.", "For example, this discussion is primarily centered on the automotive transportation industry and movement in 2-dimensional space (constrained to roads).", "This should not limit the scope of application for the present invention.", "The systems and methods described here may be applied to planes, boats, submersibles, and spacecraft.", "Many of these modes of transportation are not limited in movement to 2-dimensions;", "it follows that the discussion should not limit the present invention to operating in the vehicle transportation sector, nor in 2-dimensional space.", "[0021] FIG. 1 shows one possible embodiment of the Glide System 100 .", "Communication between the Glide Servers 110 , 170 and Glide enabled devices 131 , 132 .", "139 , 140 , 150 may occur over a WAN (Wide Area Network) 120 .", "Although FIG. 1 depicts Glide enabled devices 131 , 132 .", "139 , 140 , 150 as motorized vehicles and traffic related infrastructure, this should not limit the scope of Glide enabled devices.", "[0022] There may be multiple instances of the Glide Servers 110 , 170 .", "These different instances of the servers may serve different purposes or may store different data.", "As an example, one set of Glide Servers 110 may be responsible for data pertaining to route optimization, while another instance of the Glide Servers 170 may be responsible only for providing firmware updates to Glide Controllers 144 .", "This may mean that a Glide Controller 144 will access Glide Servers 110 exclusively when performing route optimization.", "It would then follow that, when requesting firmware updates or periodic (monthly, quarterly, yearly) data refreshing, a Glide Controller 144 may only access Glide Server 170 .", "[0023] Throughout the rest of this discussion, Glider Servers 110 in FIG. 1 will be referenced when route data is being discussed, and Glider Servers 170 in FIG. 1 will be referenced when firmware updates and locally stored data refreshing are being discussed.", "This distinction between the two different blocks of FIG. 1 should in no way limit the number or responsibilities of different instances of the Glide Servers.", "[0024] Communication 160 in the Glide System 100 may happen between Glide enabled devices 131 , 132 .", "139 , 140 , 150 and the Glide Servers 110 , 120 or between Glide enabled devices 131 , 132 .", "139 , 140 , 150 .", "Communication 160 should not be limited to the above two cases.", "Communication 160 in the Glide System 100 may include but is not limited to, 4G and 5G cellular communication, DSRC, WiFi, ZigBee, and Bluetooth.", "[0025] There may be multiple mode variations that a Glide Controller 144 may operate in.", "These may include but are not limited to, a subscription-based model;", "a stand-alone configuration;", "and OEM licensed software.", "The mode variation that a Glide Controller 144 is operating in may determine the Glide Servers 110 , 170 that specific Glide Controller 144 has access to.", "[0026] In the subscription-based model, the Glide Controller 144 in a Glide enabled device 131 , 132 .", "139 , 140 , 150 may send and receive pertinent data to and from the Glide Servers 110 to be used to optimize a route for the desired parameters.", "The subscription based model may allow Glide Controllers 144 to communicate 160 in real-time with the Glide Servers 110 to gain new information pertinent to solving the route optimization.", "This model may be similar to OnStar systems where the user 141 may pay a subscription fee for continuous use of the Glide Servers 110 .", "[0027] In the stand-alone application, the Glide Controller 144 in the Glide enabled device 131 , 132 .", "139 , 140 , 150 may not communicate 160 with the Glide Servers 110 , but may rather solve the route optimization using data included locally on the Glide Controller 144 .", "In this way, the Glide Controller 144 would not receiver data from the Glide Servers 110 that is pertinent to solving the route optimization.", "This stand-alone configuration may allow for a Glide Controller 144 to download firmware updates from the Glide Servers 170 .", "These firmware updates may include firmware that runs on a Glide Controller 144 as well as updates to the data stored locally on the Glide Controller 144 that the controller uses to solve the route optimization.", "This model may be compared to a GPS unit where the unit periodically downloads updates, but it relies on internal data for functionality.", "[0028] A third possibility is for the Glide Controller 144 to be licensed to OEM (Original Equipment Manufacturers) for use in propriety or “in-house”", "developed products.", "An example of this may be the Glide software being installed directly into the electronic vehicular control unit (e.g. ECU) 142 of an OEM vehicle instead of as an after-market add-on.", "In this realization, the Glide functionality may operate in either the connected or stand-alone mode.", "[0029] These three models should not be considered the only embodiment variations that Glide Controllers 144 may operate in.", "It should be noted that all embodiments of the Glide System 100 may include the ability to solve the route optimization problem, regardless of if it is a connected system, stand-alone, licensed to an outside party or any other embodiment the system might assume.", "[0000] I. User and/or Vehicle Interfaces [0030] FIG. 1 shows the Glide System 100 with Glide enabled devices 131 , 132 .", "139 , 140 , 150 .", "Glide enabled vehicle 140 shows that the Glide Controller 144 may include a Glide User Interface 143 .", "The Glide User Interface 143 may refer generally to a module capable of providing the user 141 a way to import route information into the Glide Controller 144 .", "More specifically, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data.", "[0031] The Glide User Interface 143 may be a user's 141 cellular device, tablet or laptop computer.", "The Glide User Interface 143 may not necessarily be installed in the Glide enabled device 140 , but may be a device that is connected via a wireless communications protocol and WAN to the Glide Controller 144 , the Glide enabled device 140 , or the Glide WAN 120 .", "In this way, the Glide Controller 144 may be controlled remotely (outside of the Glide enabled device 140 ).", "[0032] The Glide User Interface 143 may be used to receive route parameters, preferences and general data from the User 141 ;", "it may also be used to display information to the User 141 .", "Information that the Glide User Interface 143 may report the user may include but is not limited to, trip duration;", "estimated time of arrival (ETA);", "trip cost (tolls, fuel consumption cost, etc.);", "current vehicle speed;", "next target speed;", "next target location;", "trip efficiency normalized by distance relative to other trips taken;", "trip efficiency normalized by distances relative to the same trip taken without the Glide System 100 ;", "the next driving instruction;", "or warning of hazards along the route.", "[0033] The information that the Glide User Interface 143 may display should in no way be limited by the above list.", "The Glide User Interface 143 may also be integrated into the vehicle's infotainment suite.", "In this realization, the Glide User Interface 143 may be tasked with displaying other vehicle related information including but not limited to, navigation maps and directions;", "maintenance alerts;", "and entertainment related information.", "[0034] FIG. 2 shows how a Glide Controller 144 may interface with the Glide enabled device 131 , 132 .", "139 , 140 , 150 that it is installed into and the user 141 of that device (if applicable).", "The Glide Controller may communicate with multiple vehicle peripheral systems 145 , 142 , 210 , 143 including but not limited to, vehicular sensors (e.g. GPS, radar, optical sensors, wheel speed sensors, accelerometers, gyroscopes and strain gauges) 145 ;", "the electronic vehicular control unit (e.g. ECU and cruise control specific controller) 142 ;", "and the vehicular control interface (e.g. accelerator and brake pedals and cruise controls) 210 .", "[0035] FIG. 2 depicts the data between the Glide Controller 144 and vehicle's peripherals 145 , 142 , 210 , 143 may be bidirectional.", "In this case, the Glide Controller 144 may take information from the peripherals while also sending data to or manipulating them.", "[0036] The Glide Controller 144 may integrate into the Glide enabled device 131 , 132 .", "139 , 140 , 150 in multiple ways.", "The following discussion is specific to integration into a vehicle but may also apply for integration into other devices;", "further, it should not be concluded that these are the only ways the Glide Controller 144 may integrate into a physical system.", "[0037] FIG. 3 shows one way the Glide Controller 144 may be integrated into the electronics of a vehicle.", "The Glide Controller 144 may be connected to any of or multiple of the vehicle's CAN busses 360 , which means it may be able to take data from and inject data onto the vehicle's communication bus 360 .", "In this way, the Glide Controller 144 may be able to manipulate the throttle request of the vehicle by adding specific messages onto the CAN bus 360 .", "In addition to manipulating the throttle request, the Glide Controller 144 may be able to manipulate other sensors or modules in the vehicle.", "Other information the Glide Controller 144 may manipulate may include but is not limited to, Batter Management System information (tractive battery voltage, tractive battery current, output and input tractive battery power);", "cylinder activation;", "braking (regenerative deceleration, engine braking, friction braking);", "gear and neutral selection;", "4 wheel, 2 wheel, and all-wheel drive selection;", "enabling and disabling manufacturer eco modes;", "and specifying a power plant to use (electric or gas) in hybrid systems.", "This may also allow the Glide Controller 144 to collect information from the vehicular sensors 310 , 320 , 330 , 340 , 350 , 370 .", "The vehicular sensors shown in FIG. 3 are representative only and should not limit the quantity or scope of the sensors that a Glide Controller 144 may take information from or give information to.", "[0038] The Glide Controller 144 may physically connect to the vehicle's accelerator pedal 210 .", "FIG. 4 shows the functional blocks for the Speed Control Interface 440 interacting with the vehicle's user interface (pedals) 210 .", "In this way, the accelerator pedal 210 may be physically actuated by the Glide Controller 144 to adjust the acceleration of the vehicle to match the route optimization that the Glide Controller 144 has been tasked with carrying out.", "[0039] The Glide Controller 144 may physically actuate the vehicle's accelerator pedal by using a vacuum servomotor that is driven by a microcontroller.", "In this way, the Glide Controller 144 may directly actuate the vehicle's accelerator pedal 210 through an electro-mechanical output.", "This is just an example of one way to interface with the vehicle's pedal and should not be considered an exclusive or limiting example.", "[0040] The Glide Controller 144 may physically connect to the vehicle's throttle cable.", "It may connect to the cable that is physically connected to the accelerator pedal, or it may connect to the throttle cable controlled by the vehicle's cruise control system.", "In this way, the Glide Controller 144 may physically actuate the vehicle's accelerator cable, which will influence the vehicle's speed.", "[0041] The Glide Controller's 144 Speed Control Interface 440 may actuate the throttle cable(s) via a vacuum servomotor and microcontroller, similar to the connection to the accelerator pedal that was just discussed.", "This is just an example of one way to interface with the throttle cable(s) and should not be considered an exclusive or limiting example.", "[0042] The Speed Control Interface 440 may be responsible for processing the Glide Schedule received from the Glide Solver 410 .", "This Glide Schedule may be a set of discretized points that pertain to locations along the requested route.", "These points may be the same optimization points that the Glide Solver 410 produces.", "The Speed Control Interface 440 may not be the only method for manipulating the performance of the vehicle.", "The Speed Control Interface 440 may also be responsible for producing Glide control messages.", "These control messages may be electronic and used to interface with the vehicular electronic communications.", "[0043] In an embodiment where the Speed Control Interface 440 is not used to manipulate the vehicle, or the vehicular controls, a User 141 may be presented with instructions or a Glide Schedule.", "In this way, the Glide Schedule may be presented to the User 141 via instructions pertaining to how to operate the vehicle to adhere to the optimization produced by the Glide Controller 144 .", "[0044] This set of instructions (manual carrying out of the Glide Schedule) may be presented visually to the User 141 via the Glide User Interface 143 , or the instructions may be presented audibly to the User 141 , or the instructions may be presented via the vehicular GPS unit.", "The Glide Controller 144 should not be limited by these examples in how it may present instructions to the User 141 .", "[0045] The Speed Control Interface 440 may receive the Glide Schedule from a plurality of sources.", "In the embodiment where the Glide Controller 144 is present in the vehicle, the Speed Control Interface 440 may receive the Glide Schedule locally from the Glide Controller 144 .", "In the embodiment where the Glide Controller 144 and its functionality is carried out remotely (non-locally—e.g., on the Glide Servers), the Speed Control Interface 440 may receive the Glide Schedule from a remote device (Glide Servers).", "These two examples serve to explain that the Glide Schedule may be received from a plurality of sources and does not server to exclude sources that may provide the Glide Schedule.", "[0046] The Glide Schedule and Glide Schedule messages may be communicated via a plurality of methods.", "The messages may be communicated via one or multiple copper wire busses and protocols including but not limited to, UART, USART, I2C, EIA-232, CANbus, CANopen, and LIN.", "The messages may be communicated via one or multiple wireless communications protocols including but not limited to, cellular 3G, 4G and 4GLTE;", "WiFi;", "Bluetooth;", "and ZigBee.", "The Glide Schedule messages may also be communicated via an optical communications bus and protocol.", "These physical busses and messaging protocols serve as examples and should not serve as exclusive lists, but examples of possibilities.", "[0047] The Glide control messages may be sent via the same busses and protocols listed above.", "Again, this does not serve as an exclusive list for how glide control messages may be communicated, but an example of possibilities.", "[0048] While the example carried through in this description looks at manipulating the accelerator pedal of the vehicle, it should be noted that the Speed Control Interface 440 may manipulate a plurality of vehicle controls.", "These vehicular controls may include but are not limited to throttle (accelerator), brake, regenerative braking, de-acceleration, transmission controller, and power-train selection control.", "The Speed Control Interface 440 may receive Glide Schedules pertaining to the manipulation and control of any number of these or more vehicular controls.", "The Speed Control Interface 440 may produce any number of Glide control messages pertaining to and aimed at the control of any number of these or more vehicular controls.", "The Speed Controller 440 may manipulate multiple vehicular controls using multiple different methods (mechanical actuation and electronic control).", "[0049] While FIG. 3 shows the Glide Controller 144 interfacing with the vehicle electrically (by the vehicle's electronics communications bus 360 —e.g. CANbus), there are other electrical methods for the Glide Controller 144 to interact with the vehicular sensors 310 , 320 , 330 , 340 , 350 , 360 and the electronic vehicular control unit (e.g. ECU) 142 .", "The Speed Control Interface 440 may inject or send Glide control messages via the vehicular electronics communication bus 360 (e.g. CANbus).", "II.", "Glide Solver [0050] FIG. 8B shows one possible block diagram of the route processing side of the Glide System 100 .", "The Requesting Device 811 a may send a route request to the Request Manager 812 .", "The requested route may be defined by start, end and waypoints;", "start and end;", "or simply start or end.", "The Requesting Device 811 a may also define the route as GPS coordinates spaced at regular intervals along the route.", "[0051] The Requesting Device 811 a may be a User 141 , an application (via a smartphone, table, or computer).", "The Requesting Device 811 a may be the Glide User Interface 143 .", "Additionally, the Requesting Device 811 a could be the Glide WAN 120 , if a User 141 is accessing a Glide Controller 144 via the Glide WAN 120 .", "[0052] In the standalone embodiment of the system, all of the blocks shown in FIG. 8B may be present in the Glide Controller 144 that is installed in the Glide enabled device 131 , 132 .", "139 , 140 , 150 ;", "in the connected embodiment, some, all, or none of these blocks may be present in Glide Controller 144 with the others present on the Glide Servers 110 .", "[0053] Returning to FIG. 8B , the request manager may then interact with both the Glide Solver 410 and the constraint databases 815 , 816 , 816 .", "819 to provide the Glide Solver 410 with the information it needs to successfully complete the requested route optimization.", "[0054] The constraint databases 815 , 816 , 817 .", "819 may include information related to but not limited by, elevation, drag force, road speed, road curvature, road conditions, traffic, and weather.", "The Glide Solver 410 may request data from these databases to aid in the optimization of the requested route.", "[0055] The constraint databases 815 , 816 , 817 .", "819 may be stored on the Glide Servers 110 , locally on the Glide Controller 144 or in other locations accessible via the Glide System WAN 120 .", "Additionally, it may be possible to import constraint databases 815 , 816 , 817 .", "819 into the Glide Controller 144 .", "An example of this could be data pertaining to a foreign country.", "The constraint data may be read from a media storage device that is connected to the Glide Controller 144 .", "[0056] In addition to the constraint databases 815 , 816 , 817 .", "819 , the Glide Solver 410 and/or Request Manager 812 may request other information from the Glide Servers 110 , 170 , onboard memory or infrastructure servers.", "[0057] Infrastructure servers and their databases may provide the information related but not limited to current traffic conditions, traffic light timing, current throughput, current throughput goals, current lane throughput, current lane throughput goals, traffic accidents, accident avoidance instructions, and emergency vehicle avoidance instructions.", "[0058] Other Glide enabled vehicles 131 , 132 .", "139 , 140 may be a source of additional information that the Glide Solver 410 or Request Manager 812 may request data from.", "[0059] Since the breadth of information the Glide Solver 410 and Request Manager 812 has access to is large, the data resources are clearly not limited to those mentioned above.", "[0060] Referring back to FIG. 8B , the Request Manager 812 receives a route from the Requesting Device 811 a , and then requests the necessary constraint information from the constraint databases 815 , 816 , 817 .", "819 for the requested route.", "The Request Manager 812 sends the constraint information and any route parameters provided by the Requesting Device 811 a or other parameter sources to the Glide Solver 410 .", "[0061] The Glide Solver 410 , shown in FIG. 4 as part of the Glide Controller 144 , may include multiple algorithm blocks.", "Two of these blocks, shown in FIG. 4 , may be the Route Optimizer 420 and the Elevatier 430 .", "[0062] The Route optimizer 420 may be used in all variations of the Glide System 100 .", "As stated above, these may include, systems installed in vehicles, systems installed in transportation infrastructures, and systems operating in any of the modes discussed in this specification.", "[0063] When installed in a vehicle, the Route Optimizer 420 may work by minimizing any number of parameter vectors of the vehicle from the starting point to the ending point of the route.", "The flow diagrams presented in the figure set use the positive direction acceleration vector as an example;", "this should not serve as a limiting or exclusive example.", "In minimizing this positive acceleration vector, the Glide Solver 410 minimizes the energy consumption necessary to complete the requested route.", "The Glide Solver 410 may minimize the norm-2 of the positive acceleration for each point along the route, or the Glide Solver 410 may minimize a piecewise linear function of the acceleration for each point along the route.", "The method for optimization should not be limited to the two previously mentioned methods.", "Any method of optimization may be applied in the Glide Solver 410 .", "From these discrete acceleration points, the Glide Solver 410 may extrapolate and send discrete speeds that the vehicle should reach at predetermined points along the route to the Glide Controller 144 and Speed Control Interface 440 .", "[0064] The acceleration example carried through this discussion is just one of many parameters that the Glide Solver 410 and the Glide System 100 may optimize for.", "The discretized points that the Glide Solver 410 produces may be generally called a Glide Schedule.", "This Glide Schedule may include discretized points for any number of vehicle parameters.", "The Glide Schedule may pertain to but is not excluded by, acceleration, engine revolutions-per-minute (RPM), motor RPM, gear selection, powertrain selection, braking, and regeneration (regenerative braking).", "[0065] The acceleration example carried throughout this description should not limit the scope of the parameters that the Glide Solver 410 or the Glide System 100 may solve for, but rather the example should illustrate how the Glide Solver 410 and Glide System 100 go about optimizing for a given parameter.", "[0066] The Glide Solver 410 may minimize for multiple parameters.", "In this case, the Glide Solver 410 may minimize a weighted function of the multiple parameters.", "[0067] In addition to minimizing the necessary energy for the route, the Glide Solver 410 may use user-configurable options and vehicle type to optimize for other route metrics including but not limited to, monetary cost, temporal trip duration, and travel time spent idle.", "[0068] The monetary cost or a trip may include but is not limited to, vehicular operating cost, fuel cost, charging cost, and maintenance cost.", "[0069] When installed in the transportation infrastructure, the Route optimizer 420 may work much in the same way.", "It may also optimize for other metrics including but not limited to, vehicle throughput, traffic latency and prioritization for special/emergency vehicles.", "[0070] The Glide Schedule should not be thought of as a fixed solution.", "The Glide Controller 144 and Glide Solver 410 may continually adjust the Glide Schedule based on new or different data received.", "This data may be sensor data from one or more of the vehicular sensors, or this data may be received from the constraint databases 815 , 816 , 187 .", "819 .", "In this way, the Glide System 100 is continually working, optimizing, and adjusting the Glide Schedule [0071] FIG. 5 and FIG. 6 show possible flow paths for the Glide System 100 from route request to route delivery.", "FIG. 5 shows a possible flow path for a Glide System 100 that is operating in the connected mode.", "This mode, as explained above, may denote that the Glide Controller 144 in the Glide enabled device 131 , 132 .", "139 , 140 , 150 is connected to the Glide Servers 110 via the WAN 120 .", "FIG. 4B shows a possible flow path for a Glide System 100 that is operating without a final destination.", "This mode may denote that the Glide Controller 144 is simply looking a certain distance ahead of the current location and continually optimizing the route for the next x-miles.", "[0072] Step 511 in FIG. 5 describes the Requesting Device 811 a , 811 b sending route information and configuration data to the Request Manager 812 .", "The Requesting Device 811 a , 811 b may be any of a plethora of possible devices.", "In the simplest realization, the Requesting Device 811 a , 811 b may be a User 141 .", "The User 141 may input the route and configuration data via a Glide User Interface 143 .", "[0073] The User 141 may be prompted for different pieces of information related to the route to be requested.", "These pieces of information could include but are not limited to, starting and ending points of the route;", "waypoints throughout the route;", "and parameters to be optimized for.", "The Glide Controller 144 may provide (via the Glide User Interface 143 suggestions to the User 141 based on past routes or even other Glide Users with similar habits or destinations.", "[0074] The Glide Controller 144 may also predict the User's 144 routes and route preferences.", "An example of this may be predicting a route that is taken at 7:00 am every weekday morning with the starting point being the User's 141 home address, the ending point being the User's 141 work address and a waypoint at the local coffee shop.", "The Glide Controller 144 may predict this route and have the User's 141 typical preferences for this route auto-filled when the User 141 starts the system at 6:55 am.", "[0075] The Glide User Interface 143 may refer generally to a module capable of providing the User 141 a way to provide route information and parameters into the Glide Controller 144 .", "More specifically, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data.", "[0076] The Glide User Interface 143 may be a user's 141 cellular device, tablet or laptop computer.", "The Glide User Interface 143 may not necessarily be installed in the Glide enabled device 140 , but may be a device that is connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 , the Glide enabled device 140 , or the Glide WAN 120 .", "In this way, the Glide Controller 144 may be controlled remotely (outside of the Glide enabled device 140 ).", "This Glide User Interface 143 may be any device capable of accepting information from a User 141 .", "The Glide Use Interface 143 may include cellular phones, tablets, laptop computers or any other module capable of accepting inputs and communicating those inputs to the Request Manager 812 .", "[0077] In other realizations, the Requesting Device 811 a , 811 b may be a device similar to that of the Glide User Interface 143 .", "A User's 141 cellular phone, tablet, or laptop may be more than just the Glide User Interface 143 .", "The Requesting Device 811 b may not necessarily be installed in the Glide enabled device 131 , 132 .", "139 , 140 , 150 , or it may not be integrated into the Glide Controller 144 .", "The Requesting Device 811 a , 811 b may be connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 or directly to the Request Manager 812 .", "[0078] In other realizations or embodiments, the Requesting Device 811 a , 811 b may be the traffic infrastructure 150 , or the Glide Servers 110 .", "[0079] Referring back to FIG. 5 , step 511 , the Requesting Device 811 a , 811 b (discussed above) may send the route configuration data to the Request Manager 812 .", "The route information from the Requesting Device 811 a , 811 b may be defined in a plurality of manners.", "[0080] The route information may be sent as a set of locations, starting, ending and waypoints in between;", "starting and ending;", "simply starting or simply ending.", "The route information may also be sent as a list of GPS points spaced along the desired route.", "[0081] Step 512 of FIG. 5 describes the Request Manager 812 inserting points along the route to gain the necessary granularity to accurately optimize the route.", "The purpose of this step is to create more data points for the Glide Solver 410 to calculate.", "More data points along the route means the Glide Solver 410 will be able to solve for more acceleration points, and this means the speed targets will have finer resolution.", "[0082] In step 512 of FIG. 5 , the Request Manager 812 may or may not insert additional points along the route.", "If the route data from step 511 was provided as a list of GPS points, and the Request Manager 812 determines the GPS points provide an adequate level of resolution (granularity), step 512 may not be carried out.", "[0083] Step 512 in FIG. 5 should not be limited to just the Request Manager 812 .", "In some embodiments of the Glide System 100 , the data insertion may be carried out by another functional block (e.g. the Glide Solver 410 ).", "[0084] In step 513 in FIG. 5 , the Request Manager 812 may fetch the necessary data from the constraint databases 815 , 816 , 817 .", "819 .", "The constraint databases 815 , 816 , 817 .", "819 may include information related to but not limited by, elevation, road speed, and road curvature.", "The Request Manager 812 may request data from the constraint databases 815 , 816 , 817 .", "819 for each point along the requested route.", "These points may be the points created in step 512 , or they may be points provided by the Requesting Device 811 a , 811 b. [0085] The constraint databases 815 , 816 , 817 .", "819 may be stored on the Glide Servers 110 , locally on the Glide Controller 144 , or in other locations accessible via the Glide System WAN 120 .", "Additionally, it may be possible to import constraint databases 815 , 816 , 817 .", "819 into the Glide Controller 144 .", "The constraint data may also be read in from a media storage device that is connected to the local Glide Controller 144 .", "[0086] In addition to the constraint databases 815 , 816 , 817 .", "819 , the Glide Solver 410 and/or Request Manager 812 may request other information from the Glide Servers 110 , 170 , onboard memory or infrastructure servers.", "[0087] Infrastructure servers and their databases may provide the information related but not limited to current traffic conditions, traffic light timing, current throughput, current throughput goals, current lane throughput, current lane throughput goals, traffic accidents, accident avoidance instructions, and emergency vehicle avoidance instructions.", "[0088] The Request Manager 812 may request data points from all necessary constraint data bases 815 , 816 , 817 .", "819 and other data sources for all points along the request route.", "The Request Manager 812 may request data in parallel from all or some of the necessary constraint databases 815 , 816 , 817 .", "819 and other data sources, or the Request Manager 812 may queue the data requests.", "If the Request Manager 812 queues the data requests, only one constraint database 815 , 816 , 817 .", "819 may be queried at a time.", "[0089] Other Glide enabled vehicles 131 , 132 .", "139 , 140 may also be a source of additional information that the Request Manager 812 may request data from.", "[0090] In step 514 in FIG. 5 , the constraint data collected by the Request Manager 812 from the constraint databases 815 , 816 , 817 .", "819 and other data sources may be sent to the Glide Solver 410 .", "The Request Manager 812 may also send the route information, parameters and preferences that it received from the Requesting Device 811 a , 811 b to the Glide Solver 410 .", "[0091] The Glide Solver 410 may receive all of the data pertaining to the route from the Request Manager 812 at once (in bulk), or the Glide Solver 410 may receive all of the data from the Request Manager 812 in a stream as the Request Manager 812 requests the data from the constraint databases 815 , 816 , 817 .", "819 .", "[0092] In step 515 in FIG. 5 , the Glide Solver 410 may use the data it received in step 514 from the Request Manager 812 to calculate the coefficient matrices of the constraints.", "[0093] In step 516 in FIG. 5 , the Glide Solver 410 may use the coefficient matrices constructed in step 515 to minimize the acceleration vector.", "The Glide Solver 410 may be an inequality constrained norm-2 solver that uses the coefficients calculated in step 515 to minimize the norm-2 of the acceleration for each point along the route.", "[0094] The norm-2 solver referenced above is depicted in FIG. 4 .", "With reference to FIG. 4 , the Glide Solver 410 , may include multiple algorithm blocks 420 , 430 .", "One of these blocks may be an Route optimizer 420 .", "This Route optimizer 420 may be the norm-2 solver referenced above.", "The acceleration vector that is being minimized is proportional to the energy vector.", "Minimizing the acceleration vector corresponds to minimizing the energy vector.", "[0095] Included as part of step 516 in FIG. 5 may be the Glide Solver 410 producing a set of acceleration points that constitute the solution to the minimized acceleration vector.", "[0096] In step 517 in FIG. 5 , the Glide Solver 410 may use the set of acceleration points created in step 516 to create a set of speed points along the route.", "This set of speeds along the route may serve as targets for the Glide Controller 410 to aim for as the vehicle progresses through the route.", "[0097] The target speed points along the route may be calculated via the minimized acceleration vector and any other factors that are vehicle, road or driver specific that might influence the movement of the vehicle.", "Two examples of factors that may be taken into account when the Glide Solver 410 creates the set of target speed points are the vehicle's drag coefficient as well as any load the vehicle might be carrying or pulling.", "[0098] In step 518 in FIG. 5 , the Request Manager 812 may receive the route results from the Glide Solver 410 , and the Request Manager 812 may send the Glide Solver's 410 results to the Requesting Device 811 a , 811 b .", "The Request Manager 812 may also send the inputs used for the Glide Solver 410 .", "[0099] If applicable, the Requesting Device 811 a , 811 b may display the results from the Glide Solver 410 on the Glide User Interface 143 .", "The Glide User Interface 143 may display information related but not limited to, estimated trip duration;", "estimated trip cost;", "estimated time spent moving versus idle or in traffic;", "total estimated energy consumption;", "and estimated refueling/recharging locations.", "[0100] Additionally, the User 141 may be able to view the results from the Glide Solver 410 and make changes to any of the input parameters that were previously provided.", "If the User 141 makes changes to the proposed route/trip, the Glide Request Manager 812 and Glide Solver 410 may recalculate the proposed route/trip with the new preferences or parameters proposed by the User 141 .", "The Request Manager 812 and Glide Solver 410 may return the edited results to the Requesting Device 811 a , 811 b and the Glide User Interface 143 .", "The new results may be displayed along with the previous results for the User 141 to compare.", "[0101] It may follow that the User 141 could input a range of route/trip parameters and preferences and the Request Manager 812 and Glide Solver 410 may return multiple different routes for the User 141 to pick from.", "In this way, the User 141 may be able to see how different parameters affect the results of the trip optimization.", "[0102] The flow diagram in FIG. 5 should not serve as an exclusive method for the Glide System 100 to complete a route request and optimization.", "FIG. 5 merely serves as an example for one possible way for the Glide System 100 to fulfill a route request.", "[0103] FIG. 6 shows a flow diagram for another possible mode of operation for the Glide System 100 .", "In FIG. 5 , the flow diagram depicted the possible steps the Glide System 100 may take when given route parameters.", "These route parameters may include starting, ending, and waypoint destinations.", "The flow diagram in FIG. 6 shows possible steps for the Glide System 100 operating without and final destination.", "[0104] In another mode, the User 141 may simply enable the Glide Controller 144 in a Glide enabled device 131 , 132 .", "139 , 140 , 150 .", "In doing this, the Glide Controller 144 may look ahead for the next x-miles along the current route and optimize the route for the next x-miles.", "This is a functionally different mode from the previous example in that the end point is continuously moving.", "The Glide Controller 144 may continuously look ahead for the next x-miles, so the Glide Controller 144 is constantly updating its “end”", "destination.", "[0105] In step 611 in FIG. 6 , the Requesting Device 811 a , 811 b may enable the Glide Controller 144 .", "The Requesting Device 811 a , 811 b may be any of a plethora of possible devices.", "In the simplest realization, the Requesting Device 811 b may be a User 141 .", "The User 141 may enable the Glide Controller 144 via the Glide User Interface 143 .", "[0106] The Glide User Interface 143 may refer generally to a module capable of providing the User 141 a way to enable the Glide Controller 144 .", "In other modes of operation, the Glide User Interface 143 may refer generally to a module capable of providing the User 141 a way to provide route information and parameters into the Glide Controller 144 .", "More specifically, for all modes of operation, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data to and from the Glide Controller 144 .", "[0107] The Glide User Interface 143 may be a user's 141 cellular device, tablet or laptop computer.", "The Glide User Interface 143 may not necessarily be installed in the Glide enabled device 140 , but may be a device that is connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 , the Glide enabled device 140 , or the Glide WAN 120 .", "In this way, the Glide Controller 144 may be controlled remotely (outside of the Glide enabled device 140 ).", "This Glide User Interface 143 may be any device capable of accepting information from a User 141 .", "The Glide Use Interface 143 may include cellular phones, tablets, laptop computers or any other module capable of accepting inputs and communicating those inputs to the Request Manager 812 .", "[0108] In other realizations, the Requesting Device 811 a , 811 b may be a device similar to that of the Glide User Interface 143 .", "A User's 141 cellular phone, table, or laptop may be more than just the Glide User Interface 143 .", "The requesting Device 811 b may not necessarily be installed in the Glide enabled device 131 , 132 .", "139 , 140 , 150 , or it may not be integrated into the Glide Controller 144 .", "The Requesting Device 811 a , 811 b may be connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 or directly to the Request Manager 812 .", "[0109] In other realizations or embodiments, the Requesting Device 811 a , 811 b may be the traffic infrastructure 150 , or the Glide Servers 110 .", "[0110] Referring back to FIG. 6 , step 611 , the Requesting Device 811 a , 811 b (discussed above) may enabled the Glide Controller 144 .", "In the connected embodiment, this may enabled the Glide Service 100 as well.", "[0111] The User 141 may be able to use a quick select menu to choose parameters that the Glide Controller 144 and Glide Solver 410 should optimize for.", "An example of this could be: the User 141 enables the Glide Controller 144 and uses the quick select menu on the Glide User Interface 143 to tell the Glide Controller 144 to optimize for time.", "The Glide Controller 144 may then continuously optimize the next x-miles ahead of the current position for time.", "[0112] In step 612 in FIG. 6 , the Request Manager 812 may insert points along the route for the next x-miles in order to create the granularity necessary to accurately optimize the next x-miles along the current route.", "The purpose of this step is to create more data points for the Glide Solver 410 to calculate.", "More data points along the route means the Glide Solver 410 will be able to solve for more acceleration points, and this means the speed targets will have finer resolution.", "[0113] Step 612 in FIG. 6 should not be limited to just the Request Manager 812 .", "In some embodiments of the Glide System 100 , the data insertion may be carried out by another functional block (e.g. the Glide Solver 410 ).", "[0114] In step 513 in FIG. 6 , the Request Manager 812 may fetch the necessary data from the constraint databases 815 , 816 , 817 .", "819 .", "The constraint databases 815 , 816 , 817 .", "819 may include information related to but not limited by, elevation, road speed, and road curvature.", "The Request Manager 812 may request data from the constraint databases 815 , 816 , 817 .", "819 for each point along the requested route.", "These points may be the points created in step 512 , or they may be points provided by the Requesting Device 811 a , 811 b. [0115] The constraint databases 815 , 816 , 817 .", "819 may be stored on the Glide Servers 110 , locally on the Glide Controller 144 , or in other locations accessible via the Glide System WAN 120 .", "Additionally, it may be possible to import constraint databases 815 , 816 , 817 .", "819 into the Glide Controller 144 .", "The constraint data may also be read in from a media storage device that is connected to the local Glide Controller 144 .", "[0116] In addition to the constraint databases 815 , 816 , 817 .", "819 , the Glide Solver 410 and/or Request Manager 812 may request other information from the Glide Servers 110 , 170 , onboard memory or infrastructure servers.", "[0117] Infrastructure servers and their databases may provide the information related but not limited to current traffic conditions, traffic light timing, current throughput, current throughput goals, current lane throughput, current lane throughput goals, traffic accidents, accident avoidance instructions, and emergency vehicle avoidance instructions.", "[0118] The Request Manager 812 may request data points from all necessary constraint data bases 815 , 816 , 817 .", "819 and other data sources for all points along the request route.", "The Request Manager 812 may request data in parallel from all or some of the necessary constraint databases 815 , 816 , 817 .", "819 and other data sources, or the Request Manager 812 may queue the data requests.", "If the Request Manager 812 queues the data requests, only one constraint database 815 , 816 , 817 .", "819 may be queried at a time.", "[0119] Other Glide enabled vehicles 131 , 132 .", "139 , 140 may also be a source of additional information that the Request Manager 812 may request data from.", "[0120] In step 514 in FIG. 6 , the constraint data collected by the Request Manager 812 from the constraint databases 815 , 816 , 817 .", "819 and other data sources may be sent to the Glide Solver 410 .", "The Request Manager 812 may also send the route information, parameters and preferences that it received from the Requesting Device 811 a , 811 b to the Glide Solver 410 .", "[0121] The Glide Solver 410 may receive all of the data pertaining to the route from the Request Manager 812 at once (in bulk), or the Glide Solver 410 may receive all of the data from the Request Manager 812 in a stream as the Request Manager 812 requests the data from the constraint databases 815 , 816 , 817 .", "819 .", "[0122] In step 515 in FIG. 6 , the Glide Solver 410 may use the data it received in step 514 from the Request Manager 812 to calculate the coefficient matrices of the constraints.", "[0123] In step 516 in FIG. 6 , the Glide Solver 410 may use the coefficient matrices constructed in step 515 to minimize the acceleration vector.", "The Glide Solver 410 may be an inequality constrained norm-2 solver that uses the coefficients calculated in step 515 to minimize the norm-2 of the acceleration for each point along the route for the next x-miles along the current route.", "[0124] The norm-2 solver referenced above is depicted in FIG. 4 .", "With reference to FIG. 4 , the Glide Solver 410 , may include multiple algorithm blocks 420 , 430 .", "One of these blocks may be an Route optimizer 420 .", "This Route optimizer 420 may be the norm-2 solver referenced above.", "The acceleration vector that is being minimized is proportional to the energy vector.", "Minimizing the acceleration vector corresponds to minimizing the energy vector.", "[0125] Included as part of step 516 in FIG. 6 may be the Glide Solver 410 producing a set of acceleration points that constitute the solution to the minimized acceleration vector.", "[0126] In step 517 in FIG. 6 , the Glide Solver 410 may use the set of acceleration points created in step 516 to create a set of speed points along the route for the next x-miles along the current route.", "This set of speeds along the route may serve as targets for the Glide Controller 410 to aim for as the vehicle progresses through the next x-miles of the route.", "[0127] The target speed points along the route for the next x-miles may be calculated via the minimized acceleration vector and any other factors that are vehicle, road or driver specific that might influence the movement of the vehicle.", "Two examples of factors that may be taken into account when the Glide Solver 410 creates the set of target speed points are the vehicle's drag coefficient as well as any load the vehicle might be carrying or pulling.", "[0128] In step 518 in FIG. 6 , the Request Manager 812 may receive the route results from the Glide Solver 410 , and the Request Manager 812 may send the Glide Solver's 410 results to the Requesting Device 811 a , 811 b .", "The Request Manager 812 may also send the inputs used for the Glide Solver 410 .", "[0129] It should be noted that the Glide Solver 410 may provide multiple different routes for the same starting and ending destinations.", "These multiple different routes may be displayed to the User 141 , and the User 141 may be able to choose the preferred route.", "In addition to providing multiple routes, the Glide Solver 410 may provide estimations for time of arrival, energy usage, and necessary refueling or recharging.", "The estimations or additional information provided by the Glide Solver 410 should not be limited to the above listed data.", "[0130] In other embodiments, third party routing services may be used to provide the multiple different routes.", "In this embodiment, the Glide Solver 410 may then be applied to the multiple different routes provided by the third party routing services.", "[0131] If applicable, the Requesting Device 811 a , 811 b may display the results from the Glide Solver 410 on the Glide User Interface 143 .", "The Glide User Interface 143 may display information related but not limited to, estimated running cost since the Glide Controller 144 has been enabled;", "estimated and running totals of time spent moving versus idle or in traffic;", "total estimated energy consumption since the Glide Controller 144 has been enabled;", "and estimated refueling/recharging locations based on the needs of the vehicle for the next x-miles of the route.", "[0132] Additionally, the User 141 may be able to view the results from the Glide Solver 410 and make changes to the quick select optimization selections that were originally made.", "If the User 141 makes changes to the quick select optimization selections, the Glide Request Manager 812 and Glide Solver 410 may recalculate the next x-miles of the current route with the new quick select selections provided by the User 141 .", "The Request Manager 812 and Glide Solver 410 may return the edited results to the Requesting Device 811 a , 811 b and the Glide User Interface 143 .", "The new results may be displayed along with the previous results for the User 141 to compare.", "Ultimately, the User 141 may be asked to select from one of the possible optimizations of the next x-miles, or the Glide Controller 144 may default to a preset optimization setting for the next x-miles if one is not chosen.", "[0133] The flow diagram in FIG. 6 should not serve as an exclusive method for the Glide System 100 to complete a route optimization for the next x-miles of the current route.", "FIG. 6 merely serves as an example for one possible way for the Glide System 100 to fulfill a request to optimize the next x-miles of the current route.", "III.", "Elevatier (Elevation Finder) [0134] FIG. 4 shows a possible functional block for the Glide Controller 144 and Glide Solver 410 .", "The Glide Solver 410 may include specific algorithms designed to complete tasks in the Glide System 100 .", "The Elevatier 430 may be one of these algorithms.", "[0135] The Elevatier 430 may describe an algorithm specifically designed for finding a point of data (related geographically) from a very large database of information.", "While not limiting the scope of application for this algorithm, the Glide System 100 may use this algorithm for quickly finding data related to elevation along the requested route.", "The general algorithm used in the Elevatier 430 may be applied to any rapid search function tasked with querying large databases for data points.", "[0136] The index and indexing algorithm used by the Elevatier 430 may include any of a wide range of algorithms and indexing methods.", "Specifically, an rtree indexing scheme and data structure may be used to organize data.", "It may also follow that an rtree spatial indexing algorithm may be used by the Elevatier 430 to search a database.", "The spatial data structure index and the spatial indexing algorithm should not be limited to one of an rtree nature;", "the rtree example serves only to show one possibility for the structure and algorithm.", "[0137] FIG. 9 shows how elevation data may be organized to allow for the Elevatier 430 to quickly extract data need by the Glide Solver 410 .", "The configuration file 910 for the given data may be broken into N regions 921 .", "929 .", "An example of the regional level 921 .", "929 could be sections of the continental United States (west, central, and east).", "These regions may then be broken down into sub-regions 931 , 932 .", "939 , 940 .", "An example of this could be states within the larger region (Washington, Oregon, California, Arizona, Nevada and Idaho could be in the west region).", "FIG. 9 depicts two levels of data (regions 921 .", "929 and sub-regions 931 , 932 .", "939 , 940 ), but data organization should not be limited to two levels.", "Data organization levels may extend as many levels as necessary.", "To continue with the above example, the next layer could be regions within each state, then counties within each region, then cities within each county.", "[0138] All files for a given region may be stored in the same directory, and they may be indexed spatially.", "This may hold true for any region 921 .", "929 or sub-region 931 , 932 .", "939 , 940 level in the data organization scheme.", "Organization may include regions 921 .", "929 and sub-regions 931 , 932 .", "939 , 940 being stored in the same hierarchical level.", "The regions 921 .", "929 and sub-regions 931 , 932 .", "939 , 940 may also not be hierarchical.", "[0139] FIG. 10A shows how data may be manipulated between the raw data 1011 stored in memory (be it local or on a server) and the data that is accessed 1013 for delivery to the Request Manager 812 and eventually the Glide Solver 410 .", "[0140] Before the data point(s) 1014 being requested are found in the data base 1013 , the Elevatier 430 algorithm may rasterize the raw elevation data 1012 to produce and even spaced matrix 1013 of data points 1014 .", "FIG. 10A shows the matrix 1011 of un-rasterized (raw) data points 1012 .", "The Elevatier 430 algorithm may rasterized the raw data 1012 to produce a rasterized matrix 1013 of the rasterized data points 1014 .", "[0141] The Request Manager 812 may request a data point that already exists in the elevation database.", "If this is the case, the Elevatier 430 algorithm may simply rasterize the data and select the data point 1014 from the rasterized matrix 1013 .", "[0142] If the Request Manager 812 requests a data point that is not already in the elevation database, the Elevatier 430 may have to extrapolate the data point from the existing points in the database.", "[0143] There may be a functional block, included with the Elevatier that is an elevation request manager for the Elevatier.", "This elevation request manager may be different from the Request Manager 812 .", "While the Request Manager 812 may handle data between the Elevatier 430 , constraint databases 815 , 816 , 817 .", "819 , the Glide Solver 410 , and the Requesting Device 811 a , 811 b , the elevation request manager may be a front end function of the Elevatier 430 that may handle incoming data point requests.", "[0144] To obtain the extrapolated point 1015 , that the Request Manager 812 has requested, a polygon 1016 may be created around the requested point 1015 .", "The points that make up the polygon vertices may include the polygon vertices'", "locations as well as the elevation information at the polygon points.", "The point of interest 1015 (the queried elevation point) may then be extrapolated from the points surrounding it (the vertices of the polygon).", "[0145] FIG. 10A serves only to illustrate how a data point that is not already in the database may be extrapolated from surrounding data points.", "It should in no way serve as a limiting or exclusive situation.", "For example, the polygon formed by already existing, surrounding data points may be a hexagon or other polygon.", "[0146] In addition to querying data points, the Elevatier 430 algorithm may also add points 1023 to the existing databases.", "FIG. 10B shows the un-rasterized (raw) data matrix 1021 including the raw data points 1022 .", "FIG. 10B also shows a new data point 1023 may be added to the existing data set.", "In this way, the Glide System 100 may take data collected from Glide enabled devices 131 , 132 .", "139 , 140 , 150 and increase the size and accuracy of the Glide databases with this gathered information.", "[0147] FIG. 7 shows a possible flow path for the Elevatier 430 algorithm.", "FIG. 7 should in no way serve as a limiting or exclusive flow path;", "its purpose is simply to illustrate how a database querying algorithm like the Elevatier 430 could work.", "[0148] In step 710 in FIG. 7 , an elevation point may be queried by the Request Manager 812 .", "This requested data point could correspond to the geographic location of one of the route points created in step 512 or 612 in FIG. 5 and FIG. 6 , respectively.", "[0149] In step 720 a , the Elevatier 430 algorithm may search the configuration file 910 for the region(s) 921 .", "929 that include the queried point.", "[0150] To complete step 720 a , the Elevatier 430 algorithm will cycle through two nested loops.", "The first loop may cycle through the regions 921 .", "929 , and the second loop may cycle through the sub-regions 931 , 932 .", "939 , 940 .", "[0151] In step 720 b in FIG. 7 , the region counter may be set to 0.", "Step 730 a may enter the second nested loop of the Elevatier 430 algorithm.", "The initial condition of the second nested loop is to set the sub-region counter to 0 730 b. [0152] In step 740 in FIG. 7 , the polygon contacting the queried point in a particular region and sub-region is stored.", "The information stored during this step may include but is not limited to the elevation data and the accuracy associated with the elevation data.", "[0153] Steps 750 and 760 in FIG. 7 may serve as loop checks to allow the Elevatier 430 algorithm to decide when to exit one of the loops.", "The loop indexes may be positively index each loop iteration to cycle through all sub-regions 931 , 932 .", "939 and all regions 921 .", "929 .", "[0154] In step 770 in FIG. 7 , all of the elevation points stored from step 740 may be compared, and the one(s) with the highest accuracy are saved.", "[0155] In step 780 in FIG. 7 , the polygon 1016 surrounding the point of interest 1015 may be formed, and the single point of interest 1015 can be extrapolated from the polygon 1016 .", "IV.", "Glide Controller Variations [0156] A Glide Controller 144 may have different configurations within the Glide System 100 .", "Three possible variations will now be discussed.", "These three variations should in no way limit the variation possibilities of the Glide Controller 144 within or outside of the Glide System 100 .", "[0157] FIG. 8A depicts one possible variation of the Glide Controller 144 within the Glide System 100 .", "In FIG. 8A , the Glide Controller 144 may include multiple modules.", "These modules may include the Requesting Device 811 a , the Request Manager 812 and the Glide Solver 410 .", "In this configuration, the Glide Controller 144 is also the Requesting Device 811 a. [0158] In FIG. 8A , the Requesting Device 811 a is shown as a sub component of the Glide Controller 144 .", "In this way, the Glide Controller 144 may be receiving the requested route from the internal Requesting Device 811 a .", "An example of this situation may include the Glide Controller 144 optimizing for the next x-miles, without receiving an ending destination.", "[0159] In FIG. 8A , the Request Manager 812 and Glide Solver 410 are hosted locally on the Glide Controller 144 .", "This means that computation carried out by the Route Optimizer 420 and the Elevatier 430 may occur locally on the Glide Controller 144 .", "[0160] In FIG. 8A , the constraint databases 815 , 816 , 817 .", "819 are shown as existing on the Glide Servers 110 .", "It would follow that in this configuration, the Glide Controller 144 would be operating in the “connected”, subscription-based mode, where a User 141 may pay a temporally regular fee for regular communication 160 with the Glide Servers 110 .", "[0161] FIG. 8B depicts another possible variation of the Glide Controller 144 within the Glide System 100 .", "In FIG. 8B , the Glide Controller may include all of the functional blocks that have been previously discussed.", "This would include the Requesting Device 811 a , the Request Manager 812 , the Glide Solver 410 and the constraint databases 815 , 816 , 817 .", "819 .", "In this configuration, like the last, the Glide Controller 144 is also the Requesting Device 811 a. [0162] In FIG. 8B , the Requesting Device 811 a is shown as a sub component of the Glide Controller 144 .", "In this way, the Glide Controller 144 may be receiving the requested route from the internal Requesting Device 811 a .", "An example of this situation may include the Glide Controller 144 optimizing for the next x-miles, without receiving an ending destination.", "[0163] In FIG. 8B , the Request Manager 812 and Glide Solver 410 are hosted locally on the Glide Controller 144 .", "This means that computation carried out by the Route optimizer 420 and the Elevatier 430 may occur locally on the Glide Controller 144 .", "[0164] In FIG. 8B , the constraint databases 815 , 816 , 817 .", "819 are shown as existing locally on the Glide Controller 144 .", "It would follow that in this configuration, the Glide Controller 144 would be operating in the stand-alone mode, where the Glide Controller 144 may only communicate 160 with the Glide Servers 170 to apply firmware updates and database 815 , 816 , 817 .", "819 data updates.", "[0165] FIG. 8C depicts yet another possible variation of the Glide Controller 144 within the Glide System 100 .", "In FIG. 8C , the Glide Controller may include the function blocks previously discussed, the Request Manager 812 , and the Glide Solver 410 , but may not be the Requesting Device 811 b. [0166] In the FIG. 8C variation, the Requesting Device 811 a may be a module in the Glide Controller 144 (similar to FIG. 8A , FIG. 8B ), or the Requesting Device 811 b may be a User accessing the Glide System 100 via the Glide User Interface 143 , or the Requesting Device 811 b may be a device similar to that of the Glide User Interface 143 (discussed in earlier sections).", "A User's 141 cellular phone, tablet, or laptop may be used as the Requesting Device 811 b .", "The Requesting Device 811 b may not necessarily be installed in the Glide enabled device 131 , 132 .", "139 , 140 , 150 , or it may not be integrated into the Glide Controller 144 .", "The Requesting Device 811 b may be connected via a wireless communications protocol and the Glide WAN 160 to the Glide Controller 144 or directly to the Request Manager 812 .", "[0167] FIG. 8A-8C should not serve as limiting or exclusive examples of variations to the Glide Controller.", "Other examples could include a variation where the Glide Servers 110 hold all of the functional blocks including the Request Manager 812 , the Glide Controller 410 , and the constraint databases 815 , 816 , 817 .", "819 .", "In this variation, the computation carried about by the Glide Solver 410 would be carried out on the Glide Servers 110 , and the results would be sent back to the Glide Controller 144 , which may serve simply as a Glide WAN 120 terminal for the Glide User Interface 143 in a Glide enabled device 131 , 132 .", "139 , 140 , 150 .", "[0168] It should be noted that the variations discussed above are not mutually exclusive.", "For one route optimization, the variation shown in FIG. 8A may hold, where the Glide Controller 144 is also the Requesting Device 811 a (e.g., the User 141 enables the Glide Controller 144 to optimize for the next x-miles along the current route).", "That same Glide Controller 144 for its next route optimization task may assume the variation shown in FIG. 8C where the Requesting Device 811 b is the User's 141 cellular device that is requesting a route optimization from the Glide Controller 144 and the Glide System 100 .", "V. Operational Modes and Communications [0169] The different modes of operation for the Glide System 100 will now be expanded on.", "The Glide System 100 may have multiple different modes that a Glide Controller 144 may operate in, and any Glide Controller 144 may operate in multiple different modes at once.", "These are different from the Glide Controller 144 variations discussed in the previous section.", "[0170] In the connected, subscription-based mode, a Glide Controller 144 may communicate via the Glide WAN 120 with the Glide Servers 110 to obtain the information necessary for the Glide Solver 410 to optimize the request route for the desired parameters.", "In this mode, the Glide Solver 410 may use available data;", "vehicle models;", "traffic models and vehicle State of Charge models (for hybrid or electric vehicles) to calculate acceleration points;", "speed targets, optimal lanes when to apply a certain power train (internal combustion versus electric versus both);", "when to apply regenerative deceleration;", "and which gears to use for maximum efficiency.", "This is an example of parameters and solutions the Glide Solver 410 may use and carry out;", "it should by no means serve as an exclusive list for what the Glide Solver 410 and Glide System 100 may do.", "[0171] In the stand-alone application, the Glide Controller 144 in the Glide enabled device 131 , 132 .", "139 , 140 , 150 may not communicate 160 with the Glide Servers 110 , but may rather solve the route optimization using data included locally on the Glide Controller 144 .", "In this way, the Glide Controller 144 would not receiver data from the Glide Servers 110 that is pertinent to solving the route optimization.", "This stand-alone configuration may allow for a Glide Controller 144 to download firmware updates from the Glide Servers 170 .", "These firmware updates may include firmware that runs on a Glide Controller 144 as well as updates to the data stored locally on the Glide Controller 144 that the controller uses to solve the route optimization.", "This model may be compared to a GPS unit where the unit periodically downloads updates, but it relies on internal data for functionality.", "[0172] Both the subscription-based mode and the stand-alone mode may be able to carry out the same functionality in terms of route optimization.", "[0173] Both the subscription-based mode and stand-alone modes may be used with final destinations or simply with the Glide Controller 410 enabled to optimize the next x-miles on the current route.", "[0174] With infrastructure to vehicle communication 160 , a Glide Controller 144 may be operating on the traffic infrastructure 150 side of the Glide System 100 as well as in a Glide enabled vehicle 131 , 132 .", "139 , 140 .", "The infrastructure may solve for parameters including but not limited to vehicle speeds;", "optimal lanes for traffic flow and throughput;", "speed smoothing and vehicle spacing;", "occupancy or vehicle type by lanes;", "traffic light sequencing based on flow patterns;", "and traffic behavior alteration for crashes and emergency vehicles.", "A Glide Controller 144 operating on the traffic infrastructure 150 may send instructions to alter driving behavior to Glide Controllers 144 operating in Glide enabled vehicles 131 , 132 .", "139 , 140 .", "[0175] With this communication 160 from the transportation infrastructure to the vehicle, the Glide System 100 may be able to instruct vehicles to switch lanes or slow down to increase or meet a desired throughput of a particular area along a route.", "Additionally, the traffic infrastructure may be able to send instructions that will allow lane clearing for an accident ahead of a Glide enabled vehicle's 131 , 132 .", "139 , 140 current location or for an emergency/special vehicle approaching a Glide enable vehicle's 131 , 132 .", "139 , 140 location.", "[0176] The infrastructure to vehicle communication 160 may also allow the traffic infrastructure to speed smooth traffic in real-time or space vehicles for optimal travel efficiency.", "[0177] In vehicle to vehicle communication (Symbiotic Vehicular Synchronizer), one Glide Controller 144 may send notifications about upcoming events to other Glide enabled vehicles 131 , 132 .", "139 , 140 behind and around it.", "These notifications may be used by the receiving Glide Controllers 144 to adjust the optimized route in real time.", "[0178] Vehicle to vehicle communication allows the optimized route to be a fluid solution that adjusts for real time data.", "This differs from current solutions that may require all information to be routed through system servers before clients may use the information.", "In allowing for real-time vehicle to vehicle communication, the Glide System may be proactive about route decisions based on information close in time and proximity to a Glide enabled vehicle 131 , 132 .", "139 , 140 .", "[0179] Vehicle to vehicle communication may also occur via the Glide Servers.", "In this communication embodiment, a Glide enabled vehicle 131 , 132 .", "139 , 140 may communication information to the Glide Servers 110 , 170 , which may then communicate necessary information to other Glide enabled vehicles 131 , 132 .", "139 , 140 .", "The communication 160 to and from the Glide Servers 110 , 170 and the Glide enabled vehicles 131 , 132 .", "139 , 140 may occur via the Glide WAN 120 .", "In this way, the Glide System 100 may build fluid constraint databases that respond to changing environments.", "[0180] Information shared by the Symbiotic Vehicular Synchronizer may include but is not limited to, traction failure of preceding vehicles (slippery section of a lane);", "traffic for the next y-miles along the current route or routes close in proximity to the current location of the vehicle;", "vertical motion and disturbances (bumps and potholes);", "breakdowns and accidents, for route and lane avoidance;", "Glide enabled vehicle locations for convoy opportunities and enhanced diving.", "[0181] It should be noted that all modes of operation for the Glide System may use the vehicular sensor suite that may be integrated into the vehicle.", "VI.", "Modifications and Enhancements [0182] As with any system involved with a complex task, there are always additions that can be made.", "The following serves as a short list of selected features that the Glide System 100 may employ to increase the completeness of the system.", "[0183] The Glide System 100 and Glide Controller 144 may include the ability to provide supplemental information regarding the requested or optimized route.", "This may include functionality to plan out rest stops where the route plan may include when and where to refuel/recharge;", "which power plant to refuel/recharge (in a hybrid topology);", "and rest stops and food options.", "The Glide System 100 and Glide Controller 144 may provide supplemental information including but not limited to, rest-stop information, food services information, refueling and/or recharging information, and lodging information.", "[0184] The ability of the Glide System 100 to provide recommendations on where to refuel and which power plant to replenish (in a hybrid topology) may be a necessary add-on for hypermiling.", "The variation in gasoline prices coupled with the sporadic placement of charging stations means there is a large amount of variation in the refueling/recharging plan for a route, especially a lengthy route.", "[0185] The Glide System 100 may be able to compare gasoline prices for the next z-miles along the route with the availability of charge stations and their costs.", "This refueling station analysis may then be compared to the length of the route and the current state of the power plant sources (gasoline level and battery charge level).", "The Glide Controller 144 may then make a decision on the most optimal place to refuel at, given the route preferences.", "This analysis may change the way the Glide Solver 410 calculates the acceleration schedule for the vehicle [0186] An example of route manipulation due to refueling options could be the following.", "If the Glide System 100 determines the next gasoline station prices to be expensive relative to another much closer to the final destination, the Glide Controller 144 may choose to have the Glide Solver 410 re-optimize the route, but this time the Glide Solver 410 may be instructed to weight the power plant usage towards a heavier usage of the electric powertrain.", "In this way, the Glide Controller 144 will save fuel in anticipation of bypassing the more expensive refueling station in favor of the refueling station close to the final destination.", "[0187] The Glide System 100 may include the ability to optimize for holistic cost versus time balancing which may include HOV/Toll lanes and casual carpool pickups and drop-offs.", "This could also include a time flexibility parameter for situations like urgent meetings, concerts or other time sensitive activities.", "[0188] The Glide System 100 may include the ability to estimate and adjust for trailering and other vehicle alterations that may be outside of the standard vehicle models.", "The Glide System 100 may also include the ability to adjust for weather considerations: snow, rain wind, etc.", "This may include the consideration of snow-chains or whether or not the vehicle is all-wheel-drive equipped and if a route requires that or not.", "VII.", "Glide User Interface [0189] The above discussions have included references to a Glide User Interface 143 .", "This interface may be embodied in any number of different ways.", "In a general sense, the Glide User Interface 143 may refer to a module capable of providing the User 141 a way to import route information into the Glide Controller 144 .", "More specifically, the Glide User Interface 143 may be a visual feedback device with tactile or virtual buttons capable of reading data in and outputting data.", "[0190] The screen depictions discussed here should not serve as limiting or exclusive matter, but rather they should serve as examples to aid in the explanation of how the Glide User Interface 143 may function and show data.", "[0191] FIG. 11 depicts a possible screen that a User 141 could be shown while interfacing with the Glide User Interface 143 .", "1100 may be generally referred to as the home screen.", "This is the screen that the User 141 may be returned to, upon requesting so, during operation of the Glide User Interface 143 .", "[0192] FIG. 11 depicts a possible home screen 1100 with multiple choices for the User 141 .", "If the User 141 does not want to input a final destination, the User 141 may select choice 1110 , which may request that the Glide System 100 operate without an end destination and rather optimize for the next x-miles.", "The User 141 may selection choice 1120 which may send the User 141 to a screen FIG. 12 that may prompt the User 141 for more information about the new route 1200 .", "[0193] FIG. 11 may also have a My Routes selection 1130 that when selected may show the User 141 the previous routes the User 141 has selected as well as routes or destinations the User 141 has saved in an Address Book.", "The Address Book may hold destinations as well as save routes.", "An example of this could include the Address Book holding the simple address of the User's 141 office building and holding the saved route to the office building with the route preferences that the User 141 usually selects for the route to the office building.", "[0194] FIG. 11 may also present the User 141 with a Connect Device selection 1150 , which when selected, may allow the User 141 to connect an eligible device to the Glide Controller 144 .", "The User 141 may be presented with a System Settings 1150 selection, where the settings for the Glide User Interface 143 and the Glide Controller 144 may be altered.", "The User 141 may also be presented with a My Glide selection 1160 , which may allow the User 141 to view and their Glide Profile.", "[0195] FIG. 11 may also present the User 141 with a Map selection 1170 which, when selected, may take the User 141 to a map view that may show the location and current statics of the vehicle.", "This may not necessarily enabled the Glide System 100 .", "[0196] FIG. 12 was referenced above when discussing new route information.", "FIG. 12 depicts a possible screen that may generally be referred to as the New Route Selection screen 1200 .", "The New Route Selection 1200 may include multiple ways and selections for the User 141 to fill in with regards to the new route.", "The New Route Selection 1200 may prompt the User 141 with a field 1210 to input the street address of the destination.", "When 1210 is selected, an on screen keyboard may present itself to aid the User 141 in inputting data.", "Additionally, the street address 1210 may be taken in using voice commands or the native driver interface that is installed in the vehicle.", "[0197] The New Route Selection 1200 may present the User 141 with options to access previously stored addresses, trips, and points of interest (POIs) 1220 , 1260 , 1270 .", "[0198] Selection 1220 in FIG. 12 may allow the User 141 to access previously stored address.", "After selecting an address from the Address Book, the User 141 may be returned to the New Route Selection screen 1200 to input the preferred optimization for the New Route.", "[0199] Selection 1260 in FIG. 12 may allow the User 141 to access previously completed or stored trips.", "After selecting a previously stored trip, the User 141 may be returned to the New Route Selection screen 1200 to input the preferred optimization for the new route.", "It may also be possible that the previously stored trip selection may include the optimization and route preferences from that trip.", "These preferences may already be selected or highlighted when the User 141 is returned to the New Route Selection screen 1220 .", "[0200] Selection 1270 in FIG. 12 may allow the User 141 to access a database of points of interest.", "After selecting a point of interest, the User 141 may be returned to the New Route Selection screen 1200 to input the preferred optimization for the New Route.", "[0201] FIG. 12 may also present the User 141 with route optimization selections 1230 a , 1230 b , 1230 c , 1230 d .", "These choices may include but are not limited to energy 1230 a , time 1230 b , cost 1230 c , and traffic 1230 d .", "The User 141 may be able to choose any number of optimization strategies for the new route.", "It may be that the first strategy selected will be the highest priority, and the last strategy selected will be the lowest priority.", "[0202] FIG. 12 may also present the User 141 with a Route selection 1240 , which when selected may send the selected information from the above discussion to the Glide System as a Requested Route.", "[0203] FIG. 12 the New Route Selection screen 1200 may also have selections for the Map screen 1170 and the home screen 1250 .", "The Map selection 1170 which, when selected, may take the User 141 to a map view that may show the location and current statics of the vehicle.", "This may not necessarily enabled the Glide System 100 .", "The home selection 1250 , when selected, may return the User 141 to the home screen 1100 .", "[0204] FIG. 13 shows a possible depiction of the guidance screen for the Glide User Interface 143 .", "1300 may be generally referred to as the Guidance Screen.", "The Guidance Screen 1300 may include information about the vehicle and the current route.", "[0205] The Guidance Screen 1300 may display the current 1310 and target 1320 speeds for the vehicle.", "The target speed 1320 may represent the spatially next data point calculated by the Glide Solver 410 along the route.", "[0206] The Guidance Screen 1300 may display the systems calculated estimated time of arrival to the destination (if applicable).", "If the Glide System 100 is operating without a final destination, this piece of information may not be displayed.", "[0207] The Guidance Screen 1300 may display current efficiency of the trip, normalized against similar trips or a best estimated trip that doesn't use the Glide System 100 .", "The Guidance Screen 1300 may also have a Stats selection 1350 that may take the User 141 to another screen that displays more in depth stats for the trip.", "[0208] The Guidance Screen 1300 may also display information to alter the driver to the next driving operation that should be carried out as part of the trip plan.", "The map area 1360 of the Guidance Screen 1300 may display any number of different types of maps (multiple at one time or a single map at a time).", "[0209] In addition to a map 1360 , the Guidance Screen 1300 may display a Next Step section 1370 for the route.", "As shown in FIG. 13 this may include written instructions for the next step as well as a visual representation.", "Additionally, the Glide System may give an auditory message of the next step.", "[0210] The information the Guidance Screen 1300 displays should not be limited to the above discussion.", "Other information including battery state of charge, distance to next refueling station, and surrounding vehicles using the Glide System may also be displayed on the Guidance Screen 1300 .", "VIII.", "Glide Application and Web Service [0211] The Glide User Interface 143 installed in a Glide enabled device 131 , 132 .", "139 , 140 , 150 may not be the only device capable of displaying Glide System information.", "As discussed above, there may be many devices capable of acting as a Glide User Interface 143 that is not necessary installed in a Glide enabled device 131 , 132 .", "139 , 140 , 150 .", "[0212] Interaction between the User 141 and a Glide User Interface 143 may occur via a Glide Application or a Glide Web Service.", "The Glide Application or Web Service may run generally, on a computing device, and specifically, on a device with tactile or virtual buttons capable of receiving input and a method for reading information out to an operator.", "Devices may include but are not limited to, cellular telephones, tablet computers, laptop computers, desktop computers, and other variations of these devices.", "[0213] The Glide Application or Web Service may have the same functionality as the Glide User Interface described in the previous section.", "The Glide Application or Web Service may have a home screen 1100 similar to the one shown in FIG. 11 .", "It may be possible for the Glide Application or Web Service to take in route information from an operator using a screen similar to the New Route Selection screen 1200 shown in FIG. 12 .", "The Glide Application or Web Service may then store or send this information to a Glide Controller 144 .", "Additionally, the Glide Application or Web Service may be able to display real-time information pertaining to an in progress route using a screen similar to the Guidance Screen 1300 shown in FIG. 13 .", "[0214] The Glide Application or Web Service may connect to the Glide Servers 110 , 170 and directly to a Glide Controller 144 .", "The device running the Glide Application or Web Service may communicate with the Glide Servers 110 , 170 using any number of communication methods including but not limited to, 3G, 4G, or 5G cellular communication;", "or WiFi.", "The device running the Glide Application or Web Service may communicate with the Glide Controller 144 using any number of communication methods including but not limited to, 3G, 4G, or 5G cellular communication;", "WiFi, DSRC, Bluetooth, or ZigBee.", "IX.", "Glide Profile [0215] The Glide System 100 may allow Users 141 to create profiles that may be saved on the Glide Servers 110 , 170 .", "These profiles may include saved information pertaining to a particular User 141 or driver, or the profiles may include saved information pertaining to a particular vehicle.", "All types of Glide Profiles may save information pertaining to previous trips, saved addresses, saved settings/preferences, and accumulated statistics.", "Glide Profiles for either a User 141 or a Glide enabled device 131 , 132 .", "139 , 140 should not be limited in scope by the current discussion.", "[0216] A User 141 may be able to access a particular Glide Profile from any number of Glide Controllers 144 .", "This may allow a User 141 to access a particular Glide Profile from a Glide Controller 144 or Glide User Interface 143 that may not necessarily be installed in a Glide enabled device 131 , 132 .", "139 , 140 owned by the User 141 .", "[0217] Two examples of accessing a Glide Profile that may not be owned by the primary account holder may include using the Glide System 100 in a Glide enabled rental car, or using the Glide System 100 in a friend's Glide enabled vehicle.", "Continuing with the rental car example;", "a User 141 may be able to access saved routes, saved addresses, saved preferences, and saved statistics via their Glide Profile so that they may use the full extent of the Glide System 100 , while driving a Glide enabled rental vehicle.", "[0218] It may be possible for a User 141 to temporarily transfer paid Glide services to another Glide Controller 144 .", "An example of this may include, the rental car company pays only for the stand-alone Glide service, but the current User 141 (renter of the car) pays for the subscription based model with constant access to the Glide Servers 110 .", "In this example, the Glide Controller 144 in the rental car may be able to access the Glide Servers 110 , while the User's 141 Glide Profile is active on the Glide Controller 144 in the rental vehicle.", "[0219] It may be possible to access a Glide Profile from devices other than a Glide User Interface 143 .", "As discussed in the previous section, a Glide Application running on a computing device, may have the capabilities to access the Glide Servers 110 , 170 , to add and retrieve Glide Profile information.", "In this way, it may be possible for a User 141 to access a Glide Profile from a cellular device to input a destination or route parameters, save the destination or route parameters, and then access this data from a Glide User Interface 143 in a Glide enabled device 131 , 132 .", "139 , 140 .", "[0220] In sum, the present invention provides a system and methods for optimizing a vehicle's route and Glide schedule using information related but not limited to traffic, time, cost, weather, vehicular sensor data, and refueling/recharging.", "The advantages of such a system include the ability to optimize and adjust a travel route based on a limitless number of parameters and inputs that would otherwise not be possible especially if these parameters and inputs were beyond the line of sight of the vehicle's operator.", "[0221] While this invention has been described in terms of several embodiments, there are alterations, modifications, permutations, and substitute equivalents, which fall within the scope of this invention.", "Although sub-section titles have been provided to aid in the description of the invention, these titles are merely illustrative and are not intended to limit the scope of the present invention.", "[0222] It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present invention.", "It is therefore intended that the following appended claims be interpreted as including all such alterations, modifications, permutations, and substitute equivalents as fall within the true spirit and scope of the present invention." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser. No. 13/521,857 (Attorney Docket No. 46507-703.831), filed Aug. 29, 2012, now U.S. Pat. No. ______, which is a U.S. National Stage Application of International Patent Application No. PCT/DE2011/000009 (Attorney Docket No. 46507-703.601), filed Jan. 10, 2011, which claims priority to Provisional Application No. 61/335,881 (Attorney Docket No. 46507-703.101), filed Jan. 13, 2010, the full disclosures of which are incorporated herein by reference in their entirety. BACKGROUND OF THE INVENTION Field of the Invention [0002] The invention concerns an arrangement with a blood pump and a gas exchanger for extracorporeal membrane oxygenation. SUMMARY OF THE INVENTION [0003] The heart, as the central organ of the circulatory system, is a hollow muscle with two chambers, which pumps the blood in circulation by contraction and relaxation. With its left chamber (left ventricle) the blood is pumped through the arterial blood vessels of the large circulation to the blood capillaries of the periphery of the body. The blood returns to the right chamber of the heart (right ventricle) through the venous blood vessels. From there it is pumped through the pulmonary arteries in the pulmonary circulation (small circulation) to the lungs and returns via the pulmonary veins to the left ventricle. The small circulation is located very high in the chest. [0004] In cardiac disease patients can reach a position in which an artificial circulation support system becomes the only possible, and therefore life-sustaining, treatment. While in cardiac cardiac support systems which replace the pump function of the right, left or both sides of the heart a direct connection to blood vessels in the chest must be produced, the ECMO systems (extracorporeal membrane oxygenation), which work by taking over and/or supporting the entire function of the internal circulation, i.e. of the right and left chamber and the lungs, enable a simpler connection capability. [0005] ECMO systems can be connected to peripheral blood vessels. This makes so-called cannulation easier and safer and means that it can also be used outside of specialist clinics. In addition, in an acute emergency an ECMO system can be cannulated considerably faster, thereby supplying the patient with the vital life support. [0006] ECMO systems consist of a blood pump and an oxygenator, which supports the lung function and thus reduces the CO 2 in the blood and allows the O 2 to accumulate. [0007] ECMO systems can pump the blood in parallel to the internal circulation, by the blood being taken from a vein (venously) and supplied to an artery (arterially). In this case the pump pumps the blood via the arterio-venous pressure difference and thus enables, in parallel with the heart, blood flow in the periphery of the body and hence to the vital organs. [0008] In cases of pulmonary disease, the use of ECMO systems may also be the only life-sustaining treatment option. If the lungs can no longer adequately fulfil their function even by artificial respiration, all other organs suffer due to the absence of CO 2 reduction and O 2 supply and the patient reaches a life-threatening situation. [0009] In the treatment of lung diseases using ECMO systems these can also be connected to the patient intravenously, since only the function of the lungs is taken over. [0010] Current ECMO systems include oxygenators, in which the gas exchange takes place by means of membrane fiber bundles. The transport of gas takes place, as is also the case in the lungs, via the concentration gradient between the blood and the oxygen which is supplied to the oxygenator. Oxygenators currently used in ECMO systems are borrowed from heart-lung machines, such as are used in operations on the heart during cardiac surgery. [0011] The pumps of the ECMO systems are also borrowed from the heart-lung machine. Centrifugal pumps with a radial or diagonal design are used, which are driven via an electric motor. [0012] In recent times, ECMO systems have been developed which combine such centrifugal pumps and oxygenators and therefore enable more compact systems with lower filling volumes (priming volumes). These systems are stationary in use and cannot be operated directly on the patient, since they are location-dependent and need to be fixed in appropriate, rigid mountings. [0013] In the case of stable cardiac function where only one lung support is required, a system is also used in which the pressure gradient between the arterial and venous vessels is exploited to permeate the oxygenator. These systems therefore operate without a pump. [0014] Due to the relatively large surface extraneous to the body, existing ECMO systems may only be used for limited periods of time, and accompanied by the use of anticoagulant drugs. In spite of the drugs, the systems tend to lead to the formation of thrombi and must be frequently replaced. [0015] They are complicated to operate and normally require specialist personnel familiar with operating heart-lung machines. [0016] The control consoles of the systems used are relatively complex and expensive. [0017] Even if ECMO systems are now used for patient transport, the drive units are relatively heavy because for transport purposes they require a non-mains power supply to allow stand-alone operation. [0018] In the systems without a pump problems can occur if the cardiac function deteriorates during the treatment. [0019] The object of the invention is to further develop an arrangement with a blood pump and a gas exchanger for extracorporeal membrane oxygenation. [0020] This object is achieved with an arrangement of generic kind, in which the blood pump is implemented as a pulsatile blood pump and arranged with the gas exchanger in the same housing. [0021] A structure is preferably selected in which the blood inlet line is directly connected to the pulsatile blood pump without a reservoir. A reservoir, which is usually found in heart-lung machines, is unnecessary since due to the pulsatile blood pump, limited suction pressures cannot lead to the critical suction in the blood vessel. [0022] Furthermore, an arrangement is proposed in which the blood outlet line is directly connected to the gas exchanger. A filter between the blood outlet and the gas exchanger, as is usual in heart-lung machines, can be intentionally omitted, since the atraumatic overall structure and the pulsatile pumping of the blood prevents the formation of emboli so that retardation of these is not necessary. The blood inlet and outlet lines are preferably embodied as cannula or tube connections, to be able to directly connect corresponding cannulas for connection to the patient, and therefore to keep the tubes as short as possible. [0023] Such an arrangement creates a system for extracorporeal membrane oxygenation which is easily transportable as a compact unit and can be deployed quickly. The structure allows it to operate with a small number of short supply lines, with the risk of a blood clot on the surfaces of blood supply lines being further reduced. It is therefore proposed that the blood inlet line and the blood outlet line each have a length of 80 cm or less as a connection to a patient. The system operates independent of location and requires no special mountings. Non-fixed operation directly on the patient is also possible. [0024] It is advantageous if a blood inlet line arranged on the housing and a blood outlet line arranged on the housing are oriented in the same direction. This means that be particularly short cannulas can be used and the housing can be arranged as close as possible to the patient. [0025] A further reduction in the length of the cannulas can be achieved by arranging a blood outlet line and a blood inlet line on the same side of the housing. [0026] A particularly compact structure is achieved by having the pulsatile blood pump act in an axial alignment of the gas exchanger. [0027] As the preferred design variant, the pulsatile blood pump is arranged radially inside the gas exchanger. [0028] Cumulatively or alternatively, the pulsatile blood pump can be arranged on a front face of the gas exchanger. [0029] Pulsatile blood pumps, or blood pumps working according to the pulsatile principle, are pumps which work according to the positive displacement principle. In the filling phase the blood passes through the passive opening inlet valve and enters the expanding pump chamber. In the ejection phase the volume in the pump chamber is compressed and the blood is ejected through the outlet valve, which is also passive opening. [0030] According to a particularly important aspect of the invention, which is essential to the invention independently of the other features of the invention, it is proposed that the pulsatile blood pump is driven pneumatically. The pulsatile blood pump can be driven with a plunger which acts on a piston in a cylinder, or which acts on a diaphragm. However, it is advantageous if the blood pump is driven with a pulsatile gas flow. This avoids the use of electrical components. This enables the entire arrangement to operate without, or with only a minimal supply of electrical power. [0031] It is particularly advantageous if the pulsatile blood pump and the gas exchanger are connected to the same gas source. This enables the pressurized gas required for the gas exchanger to be used as a driving gas for the blood pump as well. This aspect of the invention is also essential to the invention, independently of the other features of the invention. [0032] If the gas exchanger is connected via a valve to a pulsatile compressed gas supply, one line with pulsatile compressed gas is sufficient to supply the arrangement with gas for the gas exchanger and drive gas for the pump. Either the gas outlet of the pulsatile blood pump or of the pulsatile pump drive can be connected to the gas exchanger. [0033] According to a particularly important aspect of the invention, which is also essential to the invention independently of the other features of the invention, it is proposed that the pulsatile blood pump is implemented as a balloon pump. It has a balloon and an inlet and an outlet valve. A flexible balloon is simple and inexpensive to manufacture and also shows a high level of failure reliability over numerous load cycles. [0034] According to a further particularly important aspect of the invention, which is also essential to the invention independently of the other features of the invention, it is proposed that the pulsatile blood pump is embodied as a diaphragm pump, the diaphragm of which is pre-tensioned such that its passive position is that having the maximum filling of the pump. Accordingly, the positive displacement pump is embodied by a pre-tensioned diaphragm. This must allow the greatest filling of the pump chamber in its initial position, i.e. without driving pressure or force due to a plunger. The pump can therefore be operated by positive pressure. A negative pressure, which is otherwise standard, is not required. [0035] A compact structure arises if a positive displacement pump is surrounded by bundles of membrane fibers. [0036] The balloon of the pump is preferably pneumatically driven, while the membrane can be driven pneumatically or mechanically. [0037] An advantageous arrangement comprises the inlet, inlet valve, pump chamber, outlet valve, gas exchanger fibers and outlet in the flow direction. Alternatively, an arrangement in the flow direction of inlet, inlet valve, pump chamber, gas exchanger fibers, outlet valve and outlet is proposed. Thus the gas exchange process can be improved where appropriate by applying increasing pressures. [0038] An advantageous design variant is formed by an ECMO system with a centrally arranged balloon pump, in which an annular fiber bundle is radially permeated. The annular fiber bundle can be radially permeated with a length-to-diameter ratio less than or greater than or equal to 1:1. [0039] An alternative embodiment provides a diaphragm pump mounted on an end face and a barrel-shaped fiber bundle which is diagonally permeated. This barrel-shaped fiber bundle can be diagonally permeated with a length-to-diameter ratio of less than or equal to or greater than 1 : 1 . [0040] Instead of a centrally arranged balloon pump, an end-face mounted diaphragm pump can also be provided. [0041] The gas exchanger unit can be barrel shaped, square and/or flat. Suitable valves are ball valves, conical valves, disk valves or diaphragm valves. INCORPORATION BY REFERENCE [0042] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. BRIEF DESCRIPTION OF THE DRAWINGS [0043] Different arrangements according to the invention are shown in the figures, which serve as exemplary embodiments. Shown are: [0044] FIG. 1 an ECMO system consisting of a drive console and patient system with bypass for supplying the oxygenator, [0045] FIG. 2 an arrangement in accordance with FIG. 1 with two lines between drive console and patient system, [0046] FIG. 3 an arrangement with a pressure relief valve between drive console and patient system, [0047] FIG. 4 a housing with a radially internal balloon and two radially internal valves, [0048] FIG. 5 a housing in accordance with FIG. 4 with only one radially internal valve, [0049] FIG. 6 a housing with barrel-shaped gas exchanger fibers and a blood pump arranged on an end face, [0050] FIG. 7 a housing with annularly arranged gas exchanger fibers and a blood pump arranged on an end face, [0051] FIG. 8 a housing in which the blood pump and gas exchanger are arranged side by side in parallel, and [0052] FIG. 9 a system with a mechanically powered pump. DETAILED DESCRIPTION OF THE INVENTION [0053] The basis of the invention is an ECMO system, which pumps the blood with a positive displacement pump and in which the drive power is released by the compressed respiration gas. In this arrangement the gas is fed to a pneumatically operating drive console 1 . The console generates an alternating rising and falling pressure, which is fed via a line 2 to the pump of the patient system 3 ( FIG. 1 ). [0054] After the gas has passed through the console, instead of being passed to the environment it can be fed to the oxygenator of the patient system via a separate line 4 ( FIG. 2 ). A more effective utilization of the gas is therefore obtained. [0055] Furthermore, a solution is proposed in which, as described, a rising and falling pressure is fed to the pump and on the patient system 3 a pressure relief valve 6 is connected in parallel with the pump 5 , which is connected on the other side to the gas exchanger or oxygenator 7 of the patient system, and which at the same time supplies this with respiration gas at the upper pressure level ( FIG. 3 ), There is therefore only one supply line 8 to the patient system. [0056] As described above, a pulsatile blood pump is combined with an oxygenator in a compact unit, the patient system. The following schemes are proposed for this purpose. [0057] In one scheme ( FIG. 4 ) a balloon 10 is located in the pump chamber 9 , which is centrally arranged, and this balloon 10 is pressurized and relaxed with compressed air in a pulsatile manner with a connecting hose 11 . The blood passes from the patient via a nozzle 12 and a valve 13 to reach the pumping chamber 9 . Through a second valve 14 the blood reaches the gas exchanger fibers 15 , which can be arranged in an annular pattern. These are radially permeated and the blood thus reaches the outlet 16 . Opposite the outlet 16 a ventilation port 16 is provided, to simplify the filling and bleeding of the system. [0058] In an alternative arrangement ( FIG. 5 ), the second valve 18 is located behind the gas exchanger fibers in the flow direction. [0059] In a further scheme ( FIG. 6 ) the blood passes through a valve 19 into a pump chamber 20 which is bounded on one side by a flexible diaphragm 21 , and through a second valve 22 a or 22 b to the gas exchanger fibers 23 . The membrane is connected on the other side to a connecting hose 24 and via this it is pressurized and relaxed with compressed air by the drive assembly in a pulsatile manner. The gas exchanger fibers 23 can be in a barrel-shaped ( FIG. 6 ) or annular ( FIG. 7 ) arrangement. While in the barrel-shaped arrangement the valve 22 a is seated externally, in the annular arrangement is arranged centrally 22 b. After the blood flows through the oxygenation region, diagonally in the barrel-shaped fiber arrangement or radially in the annular arrangement, it reaches the outlet 23 , positioned low down, and from there passes back to the patient. When filling the system a ventilation port 17 near the outlet is useful. This is applied at the highest point of the system. [0060] In a further scheme ( FIG. 8 ) the pump unit and the gas exchanger unit are arranged in parallel. The blood passes through a nozzle 26 and 27 via a valve into the pump chamber 28 , in which a balloon 29 is located. This is pressurized with compressed air and relaxed in a pulsatile manner via the supply line 30 . Through an additional valve 31 the blood reaches the gas exchanger fibers 32 and from there passes back to the patient via the outlet nozzle 33 . [0061] In all solutions the gas exchanger fibers are supplied with respiration gas and the respiration gas is discharged via an inlet and outlet line 34 . [0062] Is conceivable that, in the solutions with the diaphragm ( FIGS. 6 and 7 ), these are mechanically driven by a pressure plate 35 and a plunger 36 ( FIG. 9 ). For this purpose a drive console with a suitable actuator is used. This actuator can also be pneumatic. [0063] Various valve geometries are proposed for the solutions described. This means that the invention can be implemented with ball valves as shown. Conical valves, disk valves or diaphragm valves are also conceivable, however. [0064] By various geometric arrangements of the pump chambers, valves, design of the valves and oxygenator fibers in combination with both schemes, different designs emerge which facilitate an extremely compact ECMO system. [0065] It is proposed to configure the blood inlet and outlet lines in one geometric direction, in order to simplify the connection to the patient and to keep the connection cannulas as short as possible. [0066] It is proposed to produce, deliver and store the system optionally already filled, so that it is quickly ready for use. [0067] The pulsatile blood pumping has an advantageous effect on the gas exchange in the oxygenator and the elution of the whole system by a continuous mixing of the blood, and an improved elution of critical areas. Thus, the formation of thrombi is counteracted. [0068] Both functional principles, in addition to the gas exchanger can also be combined with a heat exchanger. [0069] Since the pump energy is transferred via only one gas connection (with the exception of the last solution) and not mechanically via an electric motor connected to the system as is current practice, the system can be positioned more flexibly and closer to, or on, the patient. [0070] This results in different options for driving the pulsatile pump, which makes the device combination and usage more flexible. [0071] Since oxygen for the gas exchange in the oxygenator is available in compressed form in gas cylinders or via a centralized supply line, this gas pressure can be used to also facilitate the pulsatile drive using a suitable pneumatic circuit. No additional energy source is thus required, which facilitates a more compact, simpler and less expensive drive.
The invention relates to an arrangement having a blood pump and a gas exchanger for extracorporeal membrane oxygenation. According to the invention, the blood pump is designed as a pulsatile blood pump and is arranged with the gas exchanger in the same housing. The pulsatile blood pump and the gas exchanger are preferably connected to the same gas source so that the blood pump can be pneumatically driven. The novel ECMO system has a simple design, is flexible, and in particular can be used directly on the patient.
Concisely explain the essential features and purpose of the invention.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser.", "No. 13/521,857 (Attorney Docket No. 46507-703.831), filed Aug. 29, 2012, now U.S. Pat. No. ______, which is a U.S. National Stage Application of International Patent Application No. PCT/DE2011/000009 (Attorney Docket No. 46507-703.601), filed Jan. 10, 2011, which claims priority to Provisional Application No. 61/335,881 (Attorney Docket No. 46507-703.101), filed Jan. 13, 2010, the full disclosures of which are incorporated herein by reference in their entirety.", "BACKGROUND OF THE INVENTION Field of the Invention [0002] The invention concerns an arrangement with a blood pump and a gas exchanger for extracorporeal membrane oxygenation.", "SUMMARY OF THE INVENTION [0003] The heart, as the central organ of the circulatory system, is a hollow muscle with two chambers, which pumps the blood in circulation by contraction and relaxation.", "With its left chamber (left ventricle) the blood is pumped through the arterial blood vessels of the large circulation to the blood capillaries of the periphery of the body.", "The blood returns to the right chamber of the heart (right ventricle) through the venous blood vessels.", "From there it is pumped through the pulmonary arteries in the pulmonary circulation (small circulation) to the lungs and returns via the pulmonary veins to the left ventricle.", "The small circulation is located very high in the chest.", "[0004] In cardiac disease patients can reach a position in which an artificial circulation support system becomes the only possible, and therefore life-sustaining, treatment.", "While in cardiac cardiac support systems which replace the pump function of the right, left or both sides of the heart a direct connection to blood vessels in the chest must be produced, the ECMO systems (extracorporeal membrane oxygenation), which work by taking over and/or supporting the entire function of the internal circulation, i.e. of the right and left chamber and the lungs, enable a simpler connection capability.", "[0005] ECMO systems can be connected to peripheral blood vessels.", "This makes so-called cannulation easier and safer and means that it can also be used outside of specialist clinics.", "In addition, in an acute emergency an ECMO system can be cannulated considerably faster, thereby supplying the patient with the vital life support.", "[0006] ECMO systems consist of a blood pump and an oxygenator, which supports the lung function and thus reduces the CO 2 in the blood and allows the O 2 to accumulate.", "[0007] ECMO systems can pump the blood in parallel to the internal circulation, by the blood being taken from a vein (venously) and supplied to an artery (arterially).", "In this case the pump pumps the blood via the arterio-venous pressure difference and thus enables, in parallel with the heart, blood flow in the periphery of the body and hence to the vital organs.", "[0008] In cases of pulmonary disease, the use of ECMO systems may also be the only life-sustaining treatment option.", "If the lungs can no longer adequately fulfil their function even by artificial respiration, all other organs suffer due to the absence of CO 2 reduction and O 2 supply and the patient reaches a life-threatening situation.", "[0009] In the treatment of lung diseases using ECMO systems these can also be connected to the patient intravenously, since only the function of the lungs is taken over.", "[0010] Current ECMO systems include oxygenators, in which the gas exchange takes place by means of membrane fiber bundles.", "The transport of gas takes place, as is also the case in the lungs, via the concentration gradient between the blood and the oxygen which is supplied to the oxygenator.", "Oxygenators currently used in ECMO systems are borrowed from heart-lung machines, such as are used in operations on the heart during cardiac surgery.", "[0011] The pumps of the ECMO systems are also borrowed from the heart-lung machine.", "Centrifugal pumps with a radial or diagonal design are used, which are driven via an electric motor.", "[0012] In recent times, ECMO systems have been developed which combine such centrifugal pumps and oxygenators and therefore enable more compact systems with lower filling volumes (priming volumes).", "These systems are stationary in use and cannot be operated directly on the patient, since they are location-dependent and need to be fixed in appropriate, rigid mountings.", "[0013] In the case of stable cardiac function where only one lung support is required, a system is also used in which the pressure gradient between the arterial and venous vessels is exploited to permeate the oxygenator.", "These systems therefore operate without a pump.", "[0014] Due to the relatively large surface extraneous to the body, existing ECMO systems may only be used for limited periods of time, and accompanied by the use of anticoagulant drugs.", "In spite of the drugs, the systems tend to lead to the formation of thrombi and must be frequently replaced.", "[0015] They are complicated to operate and normally require specialist personnel familiar with operating heart-lung machines.", "[0016] The control consoles of the systems used are relatively complex and expensive.", "[0017] Even if ECMO systems are now used for patient transport, the drive units are relatively heavy because for transport purposes they require a non-mains power supply to allow stand-alone operation.", "[0018] In the systems without a pump problems can occur if the cardiac function deteriorates during the treatment.", "[0019] The object of the invention is to further develop an arrangement with a blood pump and a gas exchanger for extracorporeal membrane oxygenation.", "[0020] This object is achieved with an arrangement of generic kind, in which the blood pump is implemented as a pulsatile blood pump and arranged with the gas exchanger in the same housing.", "[0021] A structure is preferably selected in which the blood inlet line is directly connected to the pulsatile blood pump without a reservoir.", "A reservoir, which is usually found in heart-lung machines, is unnecessary since due to the pulsatile blood pump, limited suction pressures cannot lead to the critical suction in the blood vessel.", "[0022] Furthermore, an arrangement is proposed in which the blood outlet line is directly connected to the gas exchanger.", "A filter between the blood outlet and the gas exchanger, as is usual in heart-lung machines, can be intentionally omitted, since the atraumatic overall structure and the pulsatile pumping of the blood prevents the formation of emboli so that retardation of these is not necessary.", "The blood inlet and outlet lines are preferably embodied as cannula or tube connections, to be able to directly connect corresponding cannulas for connection to the patient, and therefore to keep the tubes as short as possible.", "[0023] Such an arrangement creates a system for extracorporeal membrane oxygenation which is easily transportable as a compact unit and can be deployed quickly.", "The structure allows it to operate with a small number of short supply lines, with the risk of a blood clot on the surfaces of blood supply lines being further reduced.", "It is therefore proposed that the blood inlet line and the blood outlet line each have a length of 80 cm or less as a connection to a patient.", "The system operates independent of location and requires no special mountings.", "Non-fixed operation directly on the patient is also possible.", "[0024] It is advantageous if a blood inlet line arranged on the housing and a blood outlet line arranged on the housing are oriented in the same direction.", "This means that be particularly short cannulas can be used and the housing can be arranged as close as possible to the patient.", "[0025] A further reduction in the length of the cannulas can be achieved by arranging a blood outlet line and a blood inlet line on the same side of the housing.", "[0026] A particularly compact structure is achieved by having the pulsatile blood pump act in an axial alignment of the gas exchanger.", "[0027] As the preferred design variant, the pulsatile blood pump is arranged radially inside the gas exchanger.", "[0028] Cumulatively or alternatively, the pulsatile blood pump can be arranged on a front face of the gas exchanger.", "[0029] Pulsatile blood pumps, or blood pumps working according to the pulsatile principle, are pumps which work according to the positive displacement principle.", "In the filling phase the blood passes through the passive opening inlet valve and enters the expanding pump chamber.", "In the ejection phase the volume in the pump chamber is compressed and the blood is ejected through the outlet valve, which is also passive opening.", "[0030] According to a particularly important aspect of the invention, which is essential to the invention independently of the other features of the invention, it is proposed that the pulsatile blood pump is driven pneumatically.", "The pulsatile blood pump can be driven with a plunger which acts on a piston in a cylinder, or which acts on a diaphragm.", "However, it is advantageous if the blood pump is driven with a pulsatile gas flow.", "This avoids the use of electrical components.", "This enables the entire arrangement to operate without, or with only a minimal supply of electrical power.", "[0031] It is particularly advantageous if the pulsatile blood pump and the gas exchanger are connected to the same gas source.", "This enables the pressurized gas required for the gas exchanger to be used as a driving gas for the blood pump as well.", "This aspect of the invention is also essential to the invention, independently of the other features of the invention.", "[0032] If the gas exchanger is connected via a valve to a pulsatile compressed gas supply, one line with pulsatile compressed gas is sufficient to supply the arrangement with gas for the gas exchanger and drive gas for the pump.", "Either the gas outlet of the pulsatile blood pump or of the pulsatile pump drive can be connected to the gas exchanger.", "[0033] According to a particularly important aspect of the invention, which is also essential to the invention independently of the other features of the invention, it is proposed that the pulsatile blood pump is implemented as a balloon pump.", "It has a balloon and an inlet and an outlet valve.", "A flexible balloon is simple and inexpensive to manufacture and also shows a high level of failure reliability over numerous load cycles.", "[0034] According to a further particularly important aspect of the invention, which is also essential to the invention independently of the other features of the invention, it is proposed that the pulsatile blood pump is embodied as a diaphragm pump, the diaphragm of which is pre-tensioned such that its passive position is that having the maximum filling of the pump.", "Accordingly, the positive displacement pump is embodied by a pre-tensioned diaphragm.", "This must allow the greatest filling of the pump chamber in its initial position, i.e. without driving pressure or force due to a plunger.", "The pump can therefore be operated by positive pressure.", "A negative pressure, which is otherwise standard, is not required.", "[0035] A compact structure arises if a positive displacement pump is surrounded by bundles of membrane fibers.", "[0036] The balloon of the pump is preferably pneumatically driven, while the membrane can be driven pneumatically or mechanically.", "[0037] An advantageous arrangement comprises the inlet, inlet valve, pump chamber, outlet valve, gas exchanger fibers and outlet in the flow direction.", "Alternatively, an arrangement in the flow direction of inlet, inlet valve, pump chamber, gas exchanger fibers, outlet valve and outlet is proposed.", "Thus the gas exchange process can be improved where appropriate by applying increasing pressures.", "[0038] An advantageous design variant is formed by an ECMO system with a centrally arranged balloon pump, in which an annular fiber bundle is radially permeated.", "The annular fiber bundle can be radially permeated with a length-to-diameter ratio less than or greater than or equal to 1:1.", "[0039] An alternative embodiment provides a diaphragm pump mounted on an end face and a barrel-shaped fiber bundle which is diagonally permeated.", "This barrel-shaped fiber bundle can be diagonally permeated with a length-to-diameter ratio of less than or equal to or greater than 1 : 1 .", "[0040] Instead of a centrally arranged balloon pump, an end-face mounted diaphragm pump can also be provided.", "[0041] The gas exchanger unit can be barrel shaped, square and/or flat.", "Suitable valves are ball valves, conical valves, disk valves or diaphragm valves.", "INCORPORATION BY REFERENCE [0042] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.", "BRIEF DESCRIPTION OF THE DRAWINGS [0043] Different arrangements according to the invention are shown in the figures, which serve as exemplary embodiments.", "Shown are: [0044] FIG. 1 an ECMO system consisting of a drive console and patient system with bypass for supplying the oxygenator, [0045] FIG. 2 an arrangement in accordance with FIG. 1 with two lines between drive console and patient system, [0046] FIG. 3 an arrangement with a pressure relief valve between drive console and patient system, [0047] FIG. 4 a housing with a radially internal balloon and two radially internal valves, [0048] FIG. 5 a housing in accordance with FIG. 4 with only one radially internal valve, [0049] FIG. 6 a housing with barrel-shaped gas exchanger fibers and a blood pump arranged on an end face, [0050] FIG. 7 a housing with annularly arranged gas exchanger fibers and a blood pump arranged on an end face, [0051] FIG. 8 a housing in which the blood pump and gas exchanger are arranged side by side in parallel, and [0052] FIG. 9 a system with a mechanically powered pump.", "DETAILED DESCRIPTION OF THE INVENTION [0053] The basis of the invention is an ECMO system, which pumps the blood with a positive displacement pump and in which the drive power is released by the compressed respiration gas.", "In this arrangement the gas is fed to a pneumatically operating drive console 1 .", "The console generates an alternating rising and falling pressure, which is fed via a line 2 to the pump of the patient system 3 ( FIG. 1 ).", "[0054] After the gas has passed through the console, instead of being passed to the environment it can be fed to the oxygenator of the patient system via a separate line 4 ( FIG. 2 ).", "A more effective utilization of the gas is therefore obtained.", "[0055] Furthermore, a solution is proposed in which, as described, a rising and falling pressure is fed to the pump and on the patient system 3 a pressure relief valve 6 is connected in parallel with the pump 5 , which is connected on the other side to the gas exchanger or oxygenator 7 of the patient system, and which at the same time supplies this with respiration gas at the upper pressure level ( FIG. 3 ), There is therefore only one supply line 8 to the patient system.", "[0056] As described above, a pulsatile blood pump is combined with an oxygenator in a compact unit, the patient system.", "The following schemes are proposed for this purpose.", "[0057] In one scheme ( FIG. 4 ) a balloon 10 is located in the pump chamber 9 , which is centrally arranged, and this balloon 10 is pressurized and relaxed with compressed air in a pulsatile manner with a connecting hose 11 .", "The blood passes from the patient via a nozzle 12 and a valve 13 to reach the pumping chamber 9 .", "Through a second valve 14 the blood reaches the gas exchanger fibers 15 , which can be arranged in an annular pattern.", "These are radially permeated and the blood thus reaches the outlet 16 .", "Opposite the outlet 16 a ventilation port 16 is provided, to simplify the filling and bleeding of the system.", "[0058] In an alternative arrangement ( FIG. 5 ), the second valve 18 is located behind the gas exchanger fibers in the flow direction.", "[0059] In a further scheme ( FIG. 6 ) the blood passes through a valve 19 into a pump chamber 20 which is bounded on one side by a flexible diaphragm 21 , and through a second valve 22 a or 22 b to the gas exchanger fibers 23 .", "The membrane is connected on the other side to a connecting hose 24 and via this it is pressurized and relaxed with compressed air by the drive assembly in a pulsatile manner.", "The gas exchanger fibers 23 can be in a barrel-shaped ( FIG. 6 ) or annular ( FIG. 7 ) arrangement.", "While in the barrel-shaped arrangement the valve 22 a is seated externally, in the annular arrangement is arranged centrally 22 b. After the blood flows through the oxygenation region, diagonally in the barrel-shaped fiber arrangement or radially in the annular arrangement, it reaches the outlet 23 , positioned low down, and from there passes back to the patient.", "When filling the system a ventilation port 17 near the outlet is useful.", "This is applied at the highest point of the system.", "[0060] In a further scheme ( FIG. 8 ) the pump unit and the gas exchanger unit are arranged in parallel.", "The blood passes through a nozzle 26 and 27 via a valve into the pump chamber 28 , in which a balloon 29 is located.", "This is pressurized with compressed air and relaxed in a pulsatile manner via the supply line 30 .", "Through an additional valve 31 the blood reaches the gas exchanger fibers 32 and from there passes back to the patient via the outlet nozzle 33 .", "[0061] In all solutions the gas exchanger fibers are supplied with respiration gas and the respiration gas is discharged via an inlet and outlet line 34 .", "[0062] Is conceivable that, in the solutions with the diaphragm ( FIGS. 6 and 7 ), these are mechanically driven by a pressure plate 35 and a plunger 36 ( FIG. 9 ).", "For this purpose a drive console with a suitable actuator is used.", "This actuator can also be pneumatic.", "[0063] Various valve geometries are proposed for the solutions described.", "This means that the invention can be implemented with ball valves as shown.", "Conical valves, disk valves or diaphragm valves are also conceivable, however.", "[0064] By various geometric arrangements of the pump chambers, valves, design of the valves and oxygenator fibers in combination with both schemes, different designs emerge which facilitate an extremely compact ECMO system.", "[0065] It is proposed to configure the blood inlet and outlet lines in one geometric direction, in order to simplify the connection to the patient and to keep the connection cannulas as short as possible.", "[0066] It is proposed to produce, deliver and store the system optionally already filled, so that it is quickly ready for use.", "[0067] The pulsatile blood pumping has an advantageous effect on the gas exchange in the oxygenator and the elution of the whole system by a continuous mixing of the blood, and an improved elution of critical areas.", "Thus, the formation of thrombi is counteracted.", "[0068] Both functional principles, in addition to the gas exchanger can also be combined with a heat exchanger.", "[0069] Since the pump energy is transferred via only one gas connection (with the exception of the last solution) and not mechanically via an electric motor connected to the system as is current practice, the system can be positioned more flexibly and closer to, or on, the patient.", "[0070] This results in different options for driving the pulsatile pump, which makes the device combination and usage more flexible.", "[0071] Since oxygen for the gas exchange in the oxygenator is available in compressed form in gas cylinders or via a centralized supply line, this gas pressure can be used to also facilitate the pulsatile drive using a suitable pneumatic circuit.", "No additional energy source is thus required, which facilitates a more compact, simpler and less expensive drive." ]
BACKGROUND OF INVENTION This invention relates to a force measuring device and, more particularly, to a measuring device having means for compensating for zero deviation and/or span deviation attributable to temperature change. A force measuring device, such as a weigher, for converting a force into a digital electrical signal and processing the signal for display may provide a non-zero value under a no-load condition or an incorrect value under a loaded condition. The former is referred to as "zero deviation" and the latter is referred to as "span deviation", both causing an error of measurement. Although this error can be removed by adjusting the device prior to use, it often appears again with variation of the surrounding temperature. Compensating for this error by using a temperature sensing element such as a thermistor has not been sufficiently successful. The opened Japanese patent specification No. 58-95220 disclosed a device in which a reference weight having a known weight value is actually weighed and a ratio of the weight value to the indicated value is calculated and stored as a correction coefficient, thereby compensating for the span deviation. However, a number of reference weights must be prepared for obtaining high accuracy, since the correction coefficient varies with the load to be measured. It is uneconomical and troublesome to always keep and use such a number of reference weights. SUMMARY OF INVENTION Accordingly, an object of this invention is to provide an improved force measuring device having no disadvantage or problem as above-mentioned and enabling compensation for temperature-dependent zero and/or span deviations. According to this invention, there is provided a force measuring device comprising force sensing means responsive to an applied force for producing a force signal indicative of this force, temperature sensing means responsive to temperature for producing a temperature signal indicative of this temperature, means for receiving various temperature signals and corresponding force signals under no-load condition and producing, by regressive analysis, an equation indicative of the relationship between both signals, means for storing this equation, and means for calculating a zero deviation by using this equation from a current temperature signal under loaded condition, thereby correcting the current force signal. The force measuring device of this invention may further comprise means for receiving various temperature signals and corresponding force signals under reference loaded condition and producing, by regressive analysis, a second equation indicative of the relationship between both signals, means for storing the second equation, and means for calculating a span deviation by this equation from a current temperature signal under loaded condition, thereby correcting the current force signal. These and other objects and features of this invention will be described in more detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram representing a first embodiment of the force measuring device of this invention; FIG. 2 is a flow chart representing a program for obtaining an equation representing the relationship between zero deviation and temperature data in the first embodiment; FIG. 3 is a block diagram representing a second embodiment of the force measuring device of this invention; FIG. 4 is a diagram representing a temperature-dependent variation of the relationship between applied load versus its indicated value; and FIG. 5 is a block diagram representing a modified example of the force data generator 2 used in the above embodiments. DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown an embodiment of the force measuring device of this invention as a weighing device. In the drawing, 1 denotes a weighing device using a load cell of vibratory string type and 2 denotes a force data generating circuit for processing an electrical signal from the load cell to product a digital signal W indicative of the applied load or weight. The mechanical and electrical configurations of these components 1 and 2 are disclosed in detail in Japanese opened patent specification No., 59-131131 and have no direct connection to this invention. Therefore, a further description thereof will be omitted. Reference character 3 denotes a temperature sensitive element such as a thermocouple or thermistor for sensing temperature and providing a temperature indicative electrical signal to a temperature data generating circuit 4 for prossesing this signal to produce a digital signal x indicative of the sensed temperature. The circuit 4 includes an amplifier and an analog-to-digital (A/D) convertor and is well-known in the art. Therefore, no further description will be made thereon. The output digital signals W and X of both data generators 2 and 4 are stored in a memory 5 for use in determination of an equation for calculating zero deviation as described below. As well-known in the art, zero deviation Y at temperature X is generally given by a quadratic equation Y=aX 2 +bX+c. This equation is not completely determinative since the coefficients "a" and "b" and the constant "c" are variant among respective devices. According to this invention, therefore, these values are determined for each device using a technique of regressive analysis. This process will be described below with reference to the flow chart of FIG. 2. Initially, the device is unloaded and adjusted at a predetermined reference temperature such as 20° C. to indicate zero weight. Thereafter, the surrounding temperature is changed successively within a desired range of use, for example, -10° C. to +40° C. and the weight indicative signals W 0 , W 1 , . . . W n from the force data generator 2 and corresponding temperature indicative signals X 0 , X 1 , . . . X n are stored in the memory 5 in step 11. This weight and temperature data are read out by an equation generator arithmetic 6 and processed as follows. It is well-known in the field of regressive analysis that the above-mentioned coefficients "a" and "b" and constant "c" are given as follows: ##EQU1## These values of "a", "b" and "c" are calculated by step 12 in the equation generator 6. The quadratic equation aX 2 +bX+c using the calculated values is stored in another memory 7 by step 13. The memory 5 and equation generator 6 may be included in a microcomputer which is detachably coupled to the data generators 2 and 4 and the second memory 7. When the device is used for a weighing operation, a zero deviation generator 8 uses a current temperature data X from the temperature data generator 4 in the equation read out from the memory 7 to calculate the value of zero deviation Y at that time. The calculated deviation Y is subtracted from a current force data W in a subtracter 9 and the resultant zero-corrected weight value is indicated by an indicator 10. The memory 7, zero deviation generator 8 and subtracter 9 may be included in a microcomputer. FIG. 3 shows a second embodiment of this invention, which can compensate not only for zero deviation but also for span deviation. In this embodiment, the components 2 to 8 are identical to those in the first embodiment of FIG. 1. Zero deviation ε t corresponds to Y at any temperature "t" with respect to predetermined reference temperature and is provided from the zero deviation generator 8 to a correction arithmetic unit 19. FIG. 4 exaggeratedly shows temperature dependent variation of applied load versus indicated value characteristic, wherein 20° C. is selected as the reference temperature. As shown, both zero and span deviation in a force measuring device vary with temperature. Although the span deviation does not vary with variation of the applied load, it varies linearly with temperature according to the following relationship: γ.sub.t =(W.sub.t -W.sub.r)/W.sub.r where W t and W r are weight data provided by the data generators 2 at temperature "t" and the reference temperature "r", respectively, and γ t is a constant referred to as "span deviation factor". Therefore, W t =W r (1+γ t ). Considering both the span deviation and the zero deviation: W.sub.t =W.sub.r (1+γ.sub.t)+ε.sub.t Therefore, W.sub.r =(W.sub.t -ε.sub.t)/(1+γ.sub.t) (1) or W.sub.r =(W.sub.t -ε.sub.t)(1-γ.sub.t) when γ.sub.t <<1. (2) Accordingly, if the span deviation factor γ t is known, the zero and span deviations can be compensated for at any temperature using the equation (1) or (2). Although the span deviation has a linear relationship to the temperature "t", its relation to the temperature data X provided by the temperature data generator 4 is not always linear due to non-linearity of the temperature sensing element which is used. In accordance with this invention, therefore, the span deviation factor γ t is approximated as a quadratic function of the temperature data X as in the first embodiment, for example, γ t =AX 2 +BX+C. Then, the values of A, B and C are calculated by regressive analysis as described above in a second equation generator 16. This calculation is identical to that executed in the first equation generator 6 except that the weight data W i used here are previously zero-corrected in the correction arithmetic 19 and stored in a memory 15 together with the corresponding temperature data X i . The determined equation is stored in a memory 17 and used in a span deviation coefficient generator 18 with the temperature data X from the temperature data generator 4 every weighing operation for calculating the coefficient γ t at current temperature. The calculated span deviation coefficient γ t is applied to the correction arithmetic 19 together with the zero deviation ε t at the same temperature and used for calculating the zero and span-corrected weight data W r using the equation (1) or (2) which is previously stored in the unit 19. The corrected data is indicated by the indicator 10. The components 5 to 8 and 15 to 19 may be included in a microcomputer. The force data generator 2 may be of any configuration which can provide digital data. FIG. 5 shows an example of this configuration in which an analog data from a load cell 21 is amplified by an amplifier 22 and converted into digital form by an A/D convertor 23 and the resultant digital data is applied to a span correction circuit 24 for previously compensating for an inherent span error independet of temperature. In the above-mentioned embodiment, the span deviation coefficient γ t is defined as (W t -W r )/W r . However, it may be defined as W t /W r . In the latter case, an equation W r =(W t -ε t )/γ t is used in the arithmetic unit 19 instead of Equation (1) or (2). The relation between the temperature data X and ε t or γ t may be represented with another equation of higher order. The technique of regressive analysis can be used also in this case as known by those skilled in this field though the analyzing program may differ more or less. The components 5 and 6 and/or 15 and 16 used for determination of the zero deviation and span deviation factor equations, respectively, become unnecessary after determination of the equations. Therefore, it is preferable to make these components detachable from the device so that they can be used for the same purpose in other devices.
A force measuring device, such as a weighing device, having device for automatically compensating for temperature-induced zero and span deviations. The device includes force and temperature sensors for producing force and temperature indicative signals, respectively. Device for processing processes these force and temperature signals at various temperatures in no-load and reference-load conditions by regressive analysis in order to obtain and store in memory equations representing the zero and span deviations with temperature. During use of the force measuring device for measurement, the device uses the stored equations to calculate the zero and span deviations from the current temperature to correct the force indicative signal.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "BACKGROUND OF INVENTION This invention relates to a force measuring device and, more particularly, to a measuring device having means for compensating for zero deviation and/or span deviation attributable to temperature change.", "A force measuring device, such as a weigher, for converting a force into a digital electrical signal and processing the signal for display may provide a non-zero value under a no-load condition or an incorrect value under a loaded condition.", "The former is referred to as "zero deviation"", "and the latter is referred to as "span deviation", both causing an error of measurement.", "Although this error can be removed by adjusting the device prior to use, it often appears again with variation of the surrounding temperature.", "Compensating for this error by using a temperature sensing element such as a thermistor has not been sufficiently successful.", "The opened Japanese patent specification No. 58-95220 disclosed a device in which a reference weight having a known weight value is actually weighed and a ratio of the weight value to the indicated value is calculated and stored as a correction coefficient, thereby compensating for the span deviation.", "However, a number of reference weights must be prepared for obtaining high accuracy, since the correction coefficient varies with the load to be measured.", "It is uneconomical and troublesome to always keep and use such a number of reference weights.", "SUMMARY OF INVENTION Accordingly, an object of this invention is to provide an improved force measuring device having no disadvantage or problem as above-mentioned and enabling compensation for temperature-dependent zero and/or span deviations.", "According to this invention, there is provided a force measuring device comprising force sensing means responsive to an applied force for producing a force signal indicative of this force, temperature sensing means responsive to temperature for producing a temperature signal indicative of this temperature, means for receiving various temperature signals and corresponding force signals under no-load condition and producing, by regressive analysis, an equation indicative of the relationship between both signals, means for storing this equation, and means for calculating a zero deviation by using this equation from a current temperature signal under loaded condition, thereby correcting the current force signal.", "The force measuring device of this invention may further comprise means for receiving various temperature signals and corresponding force signals under reference loaded condition and producing, by regressive analysis, a second equation indicative of the relationship between both signals, means for storing the second equation, and means for calculating a span deviation by this equation from a current temperature signal under loaded condition, thereby correcting the current force signal.", "These and other objects and features of this invention will be described in more detail with reference to the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram representing a first embodiment of the force measuring device of this invention;", "FIG. 2 is a flow chart representing a program for obtaining an equation representing the relationship between zero deviation and temperature data in the first embodiment;", "FIG. 3 is a block diagram representing a second embodiment of the force measuring device of this invention;", "FIG. 4 is a diagram representing a temperature-dependent variation of the relationship between applied load versus its indicated value;", "and FIG. 5 is a block diagram representing a modified example of the force data generator 2 used in the above embodiments.", "DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown an embodiment of the force measuring device of this invention as a weighing device.", "In the drawing, 1 denotes a weighing device using a load cell of vibratory string type and 2 denotes a force data generating circuit for processing an electrical signal from the load cell to product a digital signal W indicative of the applied load or weight.", "The mechanical and electrical configurations of these components 1 and 2 are disclosed in detail in Japanese opened patent specification No., 59-131131 and have no direct connection to this invention.", "Therefore, a further description thereof will be omitted.", "Reference character 3 denotes a temperature sensitive element such as a thermocouple or thermistor for sensing temperature and providing a temperature indicative electrical signal to a temperature data generating circuit 4 for prossesing this signal to produce a digital signal x indicative of the sensed temperature.", "The circuit 4 includes an amplifier and an analog-to-digital (A/D) convertor and is well-known in the art.", "Therefore, no further description will be made thereon.", "The output digital signals W and X of both data generators 2 and 4 are stored in a memory 5 for use in determination of an equation for calculating zero deviation as described below.", "As well-known in the art, zero deviation Y at temperature X is generally given by a quadratic equation Y=aX 2 +bX+c.", "This equation is not completely determinative since the coefficients "a"", "and "b"", "and the constant "c"", "are variant among respective devices.", "According to this invention, therefore, these values are determined for each device using a technique of regressive analysis.", "This process will be described below with reference to the flow chart of FIG. 2. Initially, the device is unloaded and adjusted at a predetermined reference temperature such as 20° C. to indicate zero weight.", "Thereafter, the surrounding temperature is changed successively within a desired range of use, for example, -10° C. to +40° C. and the weight indicative signals W 0 , W 1 , .", "W n from the force data generator 2 and corresponding temperature indicative signals X 0 , X 1 , .", "X n are stored in the memory 5 in step 11.", "This weight and temperature data are read out by an equation generator arithmetic 6 and processed as follows.", "It is well-known in the field of regressive analysis that the above-mentioned coefficients "a"", "and "b"", "and constant "c"", "are given as follows: ##EQU1## These values of "a", "b"", "and "c"", "are calculated by step 12 in the equation generator 6.", "The quadratic equation aX 2 +bX+c using the calculated values is stored in another memory 7 by step 13.", "The memory 5 and equation generator 6 may be included in a microcomputer which is detachably coupled to the data generators 2 and 4 and the second memory 7.", "When the device is used for a weighing operation, a zero deviation generator 8 uses a current temperature data X from the temperature data generator 4 in the equation read out from the memory 7 to calculate the value of zero deviation Y at that time.", "The calculated deviation Y is subtracted from a current force data W in a subtracter 9 and the resultant zero-corrected weight value is indicated by an indicator 10.", "The memory 7, zero deviation generator 8 and subtracter 9 may be included in a microcomputer.", "FIG. 3 shows a second embodiment of this invention, which can compensate not only for zero deviation but also for span deviation.", "In this embodiment, the components 2 to 8 are identical to those in the first embodiment of FIG. 1. Zero deviation ε t corresponds to Y at any temperature "t"", "with respect to predetermined reference temperature and is provided from the zero deviation generator 8 to a correction arithmetic unit 19.", "FIG. 4 exaggeratedly shows temperature dependent variation of applied load versus indicated value characteristic, wherein 20° C. is selected as the reference temperature.", "As shown, both zero and span deviation in a force measuring device vary with temperature.", "Although the span deviation does not vary with variation of the applied load, it varies linearly with temperature according to the following relationship: γ.", "sub.", "t =(W.", "sub.", "t -W.", "sub.", "r)/W.", "sub.", "r where W t and W r are weight data provided by the data generators 2 at temperature "t"", "and the reference temperature "r", respectively, and γ t is a constant referred to as "span deviation factor".", "Therefore, W t =W r (1+γ t ).", "Considering both the span deviation and the zero deviation: W.sub.", "t =W.", "sub.", "r (1+γ.", "sub.", "t)+ε.", "sub.", "t Therefore, W.sub.", "r =(W.", "sub.", "t -ε.", "sub.", "t)/(1+γ.", "sub.", "t) (1) or W.sub.", "r =(W.", "sub.", "t -ε.", "sub.", "t)(1-γ.", "sub.", "t) when γ.", "sub.", "t <<1.", "(2) Accordingly, if the span deviation factor γ t is known, the zero and span deviations can be compensated for at any temperature using the equation (1) or (2).", "Although the span deviation has a linear relationship to the temperature "t", its relation to the temperature data X provided by the temperature data generator 4 is not always linear due to non-linearity of the temperature sensing element which is used.", "In accordance with this invention, therefore, the span deviation factor γ t is approximated as a quadratic function of the temperature data X as in the first embodiment, for example, γ t =AX 2 +BX+C.", "Then, the values of A, B and C are calculated by regressive analysis as described above in a second equation generator 16.", "This calculation is identical to that executed in the first equation generator 6 except that the weight data W i used here are previously zero-corrected in the correction arithmetic 19 and stored in a memory 15 together with the corresponding temperature data X i .", "The determined equation is stored in a memory 17 and used in a span deviation coefficient generator 18 with the temperature data X from the temperature data generator 4 every weighing operation for calculating the coefficient γ t at current temperature.", "The calculated span deviation coefficient γ t is applied to the correction arithmetic 19 together with the zero deviation ε t at the same temperature and used for calculating the zero and span-corrected weight data W r using the equation (1) or (2) which is previously stored in the unit 19.", "The corrected data is indicated by the indicator 10.", "The components 5 to 8 and 15 to 19 may be included in a microcomputer.", "The force data generator 2 may be of any configuration which can provide digital data.", "FIG. 5 shows an example of this configuration in which an analog data from a load cell 21 is amplified by an amplifier 22 and converted into digital form by an A/D convertor 23 and the resultant digital data is applied to a span correction circuit 24 for previously compensating for an inherent span error independet of temperature.", "In the above-mentioned embodiment, the span deviation coefficient γ t is defined as (W t -W r )/W r .", "However, it may be defined as W t /W r .", "In the latter case, an equation W r =(W t -ε t )/γ t is used in the arithmetic unit 19 instead of Equation (1) or (2).", "The relation between the temperature data X and ε t or γ t may be represented with another equation of higher order.", "The technique of regressive analysis can be used also in this case as known by those skilled in this field though the analyzing program may differ more or less.", "The components 5 and 6 and/or 15 and 16 used for determination of the zero deviation and span deviation factor equations, respectively, become unnecessary after determination of the equations.", "Therefore, it is preferable to make these components detachable from the device so that they can be used for the same purpose in other devices." ]
FIELD OF THE INVENTION The invention relates to a class of copolyesters which display optical anisotropy in the molten state and to the shaped articles, fibers and films obtained from the optically anisotropic melts. BACKGROUND OF THE INVENTION Liquid crystalline polymers (LCPs) are macromolecules possessing significant orientation in either the molten state or in concentrated solution. The state of their solution (lyotropic) or melt (thermotropic) is between the boundaries of solid crystals and isotropic liquids. In the solid state these highly ordered polymers display exceptional strength properties in the direction of orientation. By designing molecules containing only relatively inert chemical bonds, preparation of thermally and oxidatively stable high-performance materials is possible. A review of thermotropic LCPs can be found in Kwolek et al., "Liquid Crystalline Polymers", "Encyclopedia of Polymer Science and Engineering " 2nd Ed, Vol. 9, pp 23-55 (1987). Among those listed are polyesters. Many liquid crystalline polyesters display several of the desirable attributes of these compounds. Unfortunately, most have too high of a melt temperature for economical melt fabrication. There is a growing need in the thermoplastic engineering industries to provide for new and improved polyesters and copolyesters which possess a high degree of processability while concurrently exhibiting superior mechanical properties. SUMMARY OF THE INVENTION The invention concerns copolymers capable of forming an optically anisotropic melt comprising recurring structural units (a) independently each occurrence selected from the group consisting of Formula I; recurring structural units (b) independently each occurrence selected from the group consisting of Formulas II and III; and optionally recurring structural units (c) independently each occurrence selected from the group consisting of Formula IV: ##STR2## wherein R independently each occurrence is a chemically inert substituent. DETAILED DESCRIPTION Preferably, R is independently selected from the group consisting of hydrogen, halo, lower alkyl and methoxy. Most preferably, R is each occurrence hydrogen. Desirable molar percent ranges for these copolyesters are from 35 mole percent to 95 mole percent of independently recurring units of Formula I, from 5 mole percent to 50 mole percent of independently recurring units of Formulas II or from 5 mole percent to 65 mole percent of independently recurring units of Formulas III, or from 5 mole percent to 50 mole percent of independently recurring units of Formulas II, III and IV wherein the ratio of Formula II and III units to Formula IV units varies from 100:0 to 10:90. More preferable molar percent ranges for these copolyesters are from 50 mole percent to 90 mole percent of independently recurring units of Formula I, from 10 mole percent to 50 mole percent of independently recurring units of Formulas II or III, or from 10 mole percent to 50 mole percent of independently recurring units of Formulas II, III and IV wherein the ratio of Formula II and III units to Formula IV units varies from 100:0 to 10:90. The most preferred molar percent ranges are from 60 mole percent to 90 mole percent of independently recurring units of Formula I, from 10 mole percent to 40 mole percent of independently recurring units of Formulas II or III, or from 10 mole percent to 40 mole percent of independently recurring units of Formulas II, III and IV wherein the ratio of Formula II and III units to Formula IV units varies from 100:0 to 10:90. The copolymers may be formed by a variety of ester-forming techniques from difunctional organic compounds possessing functional groups which upon polycondensation form the requisite recurring units. For example, the functional groups of the organic aromatic compounds may independently contain carboxylic acid groups or acid halide groups and functional groups reactive therewith such as hydroxyl or acyloxy groups. In a preferred embodiment, the organic reactants comprise lower acyloxy and carboxylic acid functionality. For example, lower acyl esters of 4-hydroxybenzoic acid, 3-phenyl-4-hydroxybenzoic acid, 3-benzoyl-4-hydroxybenzoic acid, 3-phenoxy-4-hydroxybenzoic acid wherein the hydroxy group is esterified are more preferred as reactants. The lower acyl groups preferably have from 2 to 4 carbon atoms. Most preferably, the acetate esters are used. The organic compounds may be allowed to react under anhydrous conditions in an inert atmosphere via a melt acidolysis procedure, in a suitable solvent via a solution procedure, or in a heat exchange medium via a slurry polymerization as described in Calundann, U.S. Pat. No. 4,067,852. Additional suitable reaction conditions are described in Schaefgen, U.S. Pat. No. 4,118,372. The teachings of the foregoing U.S. patents are incorporated herein by reference. A preferable technique is the melt acidolysis technique. A catalyst may or may not be used in the polymerization process. If one is used, representative catalysts for use in the process include dialkyl tin oxides (e.g., dibutyl tin oxide), diaryl tin oxides, titanium dioxide, alkoxy titanium silicates, titanium alkoxides, Lewis acids, hydrogen halides (e.g., HCl), alkali and alkaline earth metal salts of carboxylic acids (e.g., sodium acetate). The quantity of catalyst utilized typically is from 0.001 to 1 weight percent based upon total reactant weight, and most commonly from 0.01 to 0.2 weight percent. In a preferred method of polymerization, a catalyst is not used. Liquid crystalline copolyester melts of this invention may be extruded into articles such as fibers which have outstanding strength and stiffness and will maintain their useful properties at elevated temperatures. Such fibers would be useful as tire cords, reinforcement in hoses, cables, conveyor belts or composite structures with matrixes prepared from other resinous materials. Articles may be films formed from the copolyesters which will have excellent solvent and chemical resistance. In addition, they should have low flammability and good electrical insulating properties. They would be useful as cable wrap, electric motor dielectric film and wire insulation. These copolyesters are useful for the manufacture of shaped articles such as those which are injection molded possessing high strength, stiffness, chemical resistance and low flammability. Conventional additives and processing aids can be added to the copolyester melts of the invention to improve the properties of articles made therefrom. Examples of additives are oxidation stabilizers; heat stabilizers; ultraviolet light (UV) stabilizers; lubricants; mold release agents; dyes and pigments; fibrous or powdered fillers and reinforcing agents; nucleating agents; and plasticizers. Examples of oxidation stabilizers and heat stabilizers are halides of metals of group I of the Periodic Table, used alone and used as a mixture with copper (I) halides or sterically hindered phenols in concentrations from 0.001 to 1 weight percent based on the weight of the copolyester composition. Examples of UV stabilizers are substituted resorcinols, salicylates, benzotriazoles, benzophenones and mixtures of these, which are added, for example, in amounts from 0.001 to 2 weight percent based on the weight of the copolyester composition. Dyes and pigments are used, for example, in amounts from 0.001 to 5 weight percent based on the weight of the copolyester composition. Examples are nigrosine, titanium dioxide, cadmium sulfide, phthalocyanine dyes, ultramarine blue and carbon black. Examples of fillers and reinforcing agents are carbon fibers, glass fibers, amorphous silica, calcium silicate, aluminum silicate, magnesium carbonate, kaolin, chalk, powdered quartz, mica and feldspar, which may be present in a concentration from 0.5 to 70 weight percent, based on the total weight of the filled material. Examples of nucleating agents are talc, calcium fluoride, sodium phenylphosphonate, alumina and finely divided polytetrafluoroethylene. Suitably, the nucleating agent may be present in an amount from 0.001 to 1 percent by weight. Plasticizers, such as phthalates, hydrocarbon oils and sulfonamides can be included in an amount of from 0.0001 to 20 weight percent, based on the weight of the composition. Also included in the composition of the invention, in addition to or in partial replacement of the reactants of Formulas I, II, III or IV are amounts of other aromatic polymerizable units whose presence do not interfere with the excellent mechanical properties of these copolyesters. Examples of such aromatic units comprising these additional repeating units are 2-hydroxy-6-naphthoic acid, 4-hydroxy-4'-carboxybiphenyl and 3-hydroxybenzoic acid. Preparation of 4-Acetoxybenzoic Acid An amount of 4-hydroxybenzoic acid (92.1 grams (g), 0.67 mole) was dissolved in a solution of sodium hydroxide (NaOH) (53.4 g, 1.33 moles) and 1.33 liters (L) of water in a 4 L beaker. The solution was stirred and cooled to a temperature of 0° C. by adding crushed ice, then acetic anhydride (102.1 g, 1.00 mole) was added. The temperature was maintained at -2° C. for 1 hour by adding one kilogram (kg) of crushed ice. A solution of concentrated hydrochloric acid (HCl) (144.7 g, 1.42 moles) in 267 milliliters (ml) of water was added. The slurry was stirred briefly and filtered. The product was washed twice by stirring it with 2 L portions of fresh water then filtered and dried in a vacuum oven at 80° C. for 16 hours. After recrystallization from methyl isobutyl ketone, the product consisted of 111 g of white crystals with a melting point (m.p.) of 192° C. to 192.5° C. Preparation of 3-Benzoyl-4-Acetoxybenzoic Acid A solution of benzoyl chloride (24.2 g, 0.30 mole) in 25 ml of cyclohexane was added over 5 minutes to a refluxing mixture of p-methylanisole (44.0 g, 0.36 mole), anhydrous zinc chloride (0.41 g, 3 millimoles (mmol)) and 75 ml of cyclohexane. The mixture was refluxed under nitrogen for 23 hours. After 2.5 hours, an additional 0.41 g of anhydrous zinc chloride was added. The resulting black solution was washed two times with 100 ml of 0.5N sodium hydroxide (NaOH), then with 1N hydrochloric acid (HCl), then with a 5 weight percent solution of aqueous sodium bicarbonate (NaHCO 3 ) and water. The clear yellow solution was dried with magnesium sulfate (MgSO 4 ), then the solvent was removed and the viscous yellow oil which remained was vacuum distilled through a six inch Vigreaux column. The product, 2-methoxy-5-methylbenzophenone was collected as a clear colorless oil which slowly crystallized. An amount of 2-methoxy-5-methylbenzophenone (14.2 g, 62.7 mmol) and a solution of potassium permanganate (KMnO 4 ) (24.8 g, 157 mmol) in 300 ml of water were stirred under reflux (102° C.) for one hour. The reaction mixture was cooled to 45° C. and sodium hydrogen sulfite (NaHSO 3 ) (45 g, 0.44 mole) was dissolved in the reaction mixture. Slowly 50 g of concentrated HCl was added. The white solid which was produced was taken up twice in 250 ml of ether. The combined organic phase was extracted twice with 150 ml of 0.67N NaOH. The ether phase was dried with MgSO 4 and the ether was removed. There remained 7.49 g of unreacted starting material. The combined basic extracts were acidified with concentrated HCl and extracted twice with 250 ml of ether. The ether extracts were dried with MgSO 4 and concentrated to produce 3-benzoyl-4-methoxybenzoic acid. The product was recrystallized from a mixture of 100 ml of ethanol and 200 ml of water. A solution of 3-benzoyl-4-methoxybenzoic acid (10.23 g, 40 mole), 100 ml of 48 weight percent aqueous hydrobromic acid (HBr) (149 g, 0.88 mole) and 200 ml of acetic acid was refluxed under nitrogen. After five hours, a white solid began to separate. After 22 hours, the slurry was cooled in ice and filtered. The white solid which was collected was washed with water and dried in a vacuum oven. There remained white granular 3-benzoyl-4-hydroxybenzoic acid. Acetic anhydride (10.5 g, 0.103 mmol) was added to a solution of 3-benzoyl-4-hydroxybenzoic acid (12.5 g, 51.6 mole) and NaOH (4.33 g, 0.108 mmol) in 250 ml of water under nitrogen. The clear colorless solution was stirred at 8° C. for one hour. The product separated initially as a colorless oil which soon crystallized to a white solid. The slurry was made strongly acidic by adding concentrated HCl, and was extracted with ether. The ether extract was washed with water, and dried with MgSO 4 and evaporated to dryness providing crude acetoxy acid. The crude product was recrystallized from a mixture of 200 ml of toluene and 150 ml of cyclohexane to give 3-benzoyl-4-acetoxybenzoic acid with a m.p. of 162.5° C. to 163° C. Preparation of 3-Phenyl-4-Acetoxybenzoic Acid A solution of 2-hydroxybiphenyl (51.2 g, 0.300 mole), 50 weight percent aqueous NaOH solution (28.6 g, 0.360 mole) and 120 ml of deionized water were added to a one-liter, three-necked, round-bottom flask equipped with a cold water condenser, nitrogen inlet, thermometer, and an air-powered paddle stirrer. The solution was stirred under nitrogen until homogeneous, then 175 ml of a methylene chloride solution of bromoethane (65.3 g, 0.600 mole) and tetrabutylammonium bromide (9.70 g, 0.030 mole) was added with vigorous stirring. The reaction mixture was stirred at room temperature for 22 hours. The mixture was transferred to a one-liter separatory funnel and the organic layer was decanted and saved. Before discarding the aqueous layer, it was extracted with 25 ml of methylene chloride. The methylene chloride extract was added to the organic reaction solution which was added to a bottle containing 100 ml of 10 weight percent aqueous NaOH solution. The mixture was shaken vigorously for 0.5 hours on a mechanical shaker. The separated aqueous layer was discarded. The organic layer was washed twice with 50 ml of 1N HCl followed by a 50 ml deionized water wash. The organic solution was stored over anhydrous MgSO 4 for several hours then the solvent was removed by rotary evaporation to provide a salmon-colored liquid. The sides of the flask were scraped with a glass stirring rod inducing crystallization of the product, 2-ethoxybiphenyl. A solution of 2-ethoxybiphenyl (19.8 g, 0.100 mole) and 100 ml of carbon disulfide were added to a 250-ml, three-necked, round-bottom reaction flask equipped with a cold water condenser, nitrogen inlet, thermometer and polytetrafluoroethylene-coated magnetic stir bar. The solution was maintained under nitrogen and brought to a mild reflux at approximately 46° C. Anhydrous aluminum chloride (AlCl 3 ) (13.8 g, 0.104 mole) was added slowly to the refluxing solution via a dropping funnel. A green, heterogeneous mixture was formed. Approximately 60 ml of a carbon disulfide solution containing acetyl chloride (8.07 g, 0.103 mole) was added dropwise to the refluxing reaction solution over 100 minutes. The reaction solution was refluxed for an additional hour after the last acetyl chloride addition, then cooled to room temperature. The reaction solution was poured slowly into a cold HCl solution and stirred. The contents were then transferred to a 500 ml separatory funnel, shaken, and the separated organic layer was stored over anhydrous MgSO 4 . Before discarding, the aqueous layer was washed with 25 ml of layer. The dried organic layer was filtered and the volatiles were rotary evaporated off leaving a tan solid which was dried under vacuum at 60° C. for two hours yielding a crude product. The solid was recrystallized from hexane to give 3-phenyl-4-ethoxyacetophenone. A mixture of 3-phenyl-4-ethoxyacetophenone (32.2 g, 0.134 mole) and 250 ml of p-dioxane was added to a one-liter, three-necked, round-bottom flask equipped with a pressure equalizing dropping funnel, thermometer and a polytetrafluoroethylene-coated magnetic stir bar. The mixture was stirred to dissolve the solid, then 480 mi of sodium hypobromite solution (0.53 mole), prepared by dissolving NaOH (126 g, 3.15 moles) in 600 ml of deionized water, followed by dropwise addition of 45 ml of bromine (0.87 mole) over a 60 minute time period, was added. The solution temperature rose from 22° C. to 48° C. during the addition. The reaction solution was stirred an additional 15 minutes after the last of the NaOBr addition, then a solution of 40 weight percent aqueous NaHSO 3 (41.9 g, 1.61 moles) was added to remove any remaining NaOBr. The solution was then immersed in an ice bath and acidified to a pH of 2 with concentrated HCl. A light yellow solid precipitated upon acidification. The solid was filtered, recrystallized from a dioxane and water mixture, filtered and dried under vacuum at 60° C. overnight to yield a light yellow solid of 3-phenyl-4-ethoxybenzoic acid. A solution of 3-phenyl-4-ethoxybenzoic acid (26.6 g, 0.110 mole) and 550 ml of acetic acid was added to a one-liter, three-necked, round-bottom flask equipped with a 250 ml pressure equalizing dropping funnel, thermometer, cold water condenser, nitrogen inlet adapter and a polytetrafluoroethylene-coated magnetic stir bar. The flask was purged with nitrogen and the solution was brought to reflux. Approximately 125 ml of a 48 weight percent solution of HBr was added dropwise over fifteen minutes to the refluxing solution. The solution was refluxed for 30 hours. Without cooling, the solvent was rotary evaporated off leaving a slurry of a pinkish solid. The slurry was poured into one liter of deionized water and the mixture was stirred for one hour and filtered. The filter cake was dried in an 80° C. vacuum oven for three hours yielding 3-phenyl-4-hydroxybenzoic acid. A solution of 3-phenyl-4-hydroxybenzoic acid (131.1 g, 0.061 mole) and a 50 weight percent aqueous solution of NaOH (10.5 g, 0.131 mole) in 350 ml of deionized water was added to a 500 ml, three-necked, round-bottom flask equipped with a thermometer and a polytetrafluoroethylene-coated magnetic stir bar. The solution was stirred to homogeneity and then immersed in an ice water bath. With the solution temperature at 10° C., acetic anhydride (12.7 g, 0.124 mole) was added rapidly with stirring. Immediately, a white precipitate began to form. The reaction mixture was stirred for one hour at 10° C., then neutralized with concentrated HCl. The precipitate was filtered, washed in 500 ml of deionized water for one hour, filtered, and dried in an 80° C. vacuum oven for three hours yielding an off-white solid. The solid was recrystallized from a toluene and hexane mixture to give a fluffy white solid, 3-phenyl-4-acetoxybenzoic acid with a m.p. of 185° C. to 187° C. Preparation of 3-Phenoxy-4-Acetoxybenzoic Acid A solution of bromine (79.9 g, 0.500 mole) in 100 ml of carbon tetrachloride (CCl 4 ) was slowly added over a 15 minute period to a stirred solution of 4-methylanisole (61.1 g, 0.500 mole) in 400 ml Of CCl 4 at 25° C. in the dark. Gaseous HBr evolved. Slight cooling was used to keep the temperature at 25° C. to 30° C. After 1.5 hours, the evolution of HBr stopped and the deep red solution was allowed to stand in the dark overnight. The reaction mass was washed with aqueous solutions of NaHSO 3 and NaHCO 3 , then with water. The solution was dried, concentrated and vacuum distilled through a 30 cm column packed with ceramic saddles. The fraction boiling between 102° C. and 105° C. at 8 mm Hg was collected. The product, 2-bromo-4-methylanisole was a clear colorless liquid. A stirred mixture of phenol (20.7 g, 0.220 mole) and powdered KOH (12.3 g, 0.220 mole) was slowly heated to 167° C. under nitrogen. At 120° C., the reaction mass became a clear colorless liquid. The pressure was slowly reduced. At 150 mm Hg, water began to distill. When most of the water had been removed, the reaction mass solidified. The white solid was held at 167° C. and 1 mm Hg for 30 minutes to remove the last traces of water, then cooled to room temperature. Electrolytic copper dust (70 milligrams (mg), 0.0011 gram-atoms), 2-bromo-4-methylanisole (40.4 g, 0.200 mole) and phenol (10.4 g, 0.110 mole) were added, then the flask was lowered into an oil bath that had been preheated to 200° C. All the solid dissolved. The dark red liquid was stirred under nitrogen at 200° C. for 3.5 hours. The reaction mass was cooled, diluted with 500 ml of ether, and washed three times with 100 ml portions of 1N NaOH, then with 1N HCl, then with 5 weight percent aqueous NaHCO 3 solution and with water. The solution was filtered to remove a few droplets of undissolved black tar, then cooled in dry ice. The product, 2-phenoxy-4-methylanisole separated as an oil which slowly crystallized. A solution of 2-phenoxy-4-methylanisole (26.9 g, 0.126 mole), KMnO 4 (48.8 g, 0.315 mole), 240 ml of deionized water and 480 ml of pyridine was added to a two-liter, one-necked, round-bottom flask equipped with a reflux condenser and a polytetrafluoroethylene-coated magnetic stir bar. The solution was brought to reflux while stirring for 1.5 hours at which point the solution was brown and the heating mantle was removed. The mixture was brought to near dryness on a rotary evaporator. Approximately 250 ml of deionized water was added to the flask with NaHSO 3 (41.6 g, 0.400 mole). Concentrated HCl was added slowly to the aqueous solution resulting in the precipitation of an off-white solid. The solid was filtered and washed in 600 ml of deionized water for one hour, refiltered and dissolved in 250 ml of deionized water with NaOH (0.15 mole). The aqueous solution was extracted with 125 ml of ether to remove unreacted starting material. The aqueous layer was added dropwise into a rapidly stirred dilute acid solution of HCl (0.2 mole) in 600 mi of water, resulting in the precipitation of a white, finely divided solid. The white solid was collected and dried at 100° C. under vacuum for four hours yielding an off-white solid that was 3-phenoxy-4-methoxybenzoic acid. A solution of 3-phenoxy-4-methoxybenzoic acid (17.0 g, 0.07 mole), a 48 weight percent aqueous solution of HBr (165 ml, 1.39 mole) and 350 ml of glacial acetic acid was added to a 1-liter, one-necked, round-bottom flask equipped with a reflux condenser, nitrogen inlet adapter and a polytetrafluoroethylene-coated magnetic stir bar. The solution was heated under nitrogen and refluxed for 16 hours. While still hot, the flask was transferred to a rotary evaporator and the volatiles were removed leaving a salmon-colored solid which was added to 200 ml of 1.25N NaOH solution (0.25 mole). Most of the solid dissolved. The insoluble portion was filtered off. The remaining aqueous base solution was added dropwise to a stirred aqueous HCl solution (0.25 mole in 400 ml deionized water) resulting in the precipitation of a salmon-colored solid. The solid was washed in 300 ml of deionized water for 1 hour, filtered, dried at room temperature overnight, and dried under vacuum at 100° C. for 1 hour yielding 3-phenoxy-4-hydroxybenzoic acid. A solution of 3-phenoxy-4-hydroxybenzoic acid (13.9 g, 0.0560 mole), 200 ml of deionized water, and NaOH (11.2 g of 50 weight percent aqueous solution, 0.140 mole) was added to a 500-ml conical flask equipped with a thermometer and a polytetrafluoroethylene-coated magnetic stir bar. The reaction flask was immersed in an ice bath and stirred. Acetic anhydride (12.2 g, 0.120 mole) was added rapidly to the stirred solution causing a temperature increase from 7° C. to 12° C. Approximately one minute after the acetic anhydride addition, a precipitate began to appear. The solution was stirred for one hour at 5° C. to 7° C. and was neutralized with concentrated HCl (15 g, 0.15 mole) causing further precipitation. The off-white precipitate was filtered and washed with 200 ml of deionized water for one hour, refiltered and dried at 80° C. under vacuum for two hours yielding an off-white solid. This product was recrystallized from toluene, filtered and dried one hour under vacuum to yield an off-white solid which was 3-phenoxy-4-acetoxybenzoic acid with a m.p. of 181° C. to 183° C. Having described the invention, the following examples are provided as further illustrative and are not to be construed as limiting. General Melt Polymerization Procedure Small-scale melt polymerizations were carried out in 15 mm internal diameter (I.D.) polymerization tubes for 1 to 3 g quantities and in 24 mm I.D. polymerization tubes for 6 g quantities. The tubes were fitted with a head equipped with an adjustable capillary tube, a combined distillate delivery tube and air condenser, a receiver and a combined nitrogen inlet and vacuum port. The lower portion of the polymerization tube was heated in a small, vertical hot air oven. After the reactants were added to the polymerization tube, it was evacuated and refilled with nitrogen three times, then heated to 260° C. After the reactants had melted to form a liquid reaction mass, a capillary tube was lowered below the liquid surface and the nitrogen flow was adjusted to show a slow stream of bubbles passing through the liquid. The polymerization was held at 260° C. until about one half of the theoretical amount of acetic acid had been collected. At this point, the temperature was increased and the pressure was reduced at a rate sufficient to keep the rate of acetic acid evolution steady. A typical heating schedule was 1 hour at 260° C., 1 hour at 300° C. and 1 hour at 320° C. The liquid was then put under vacuum of 1 mm Hg at 340° C. for 30 minutes. The viscosity of the reaction mass was periodically measured by moving the capillary through the liquid. The capillary was raised to a position about 1 cm above the reaction mass before the mass became solid or extremely viscous. The polymerization was stopped when approximately all the theoretically calculated amount of acetic acid had been collected. The reaction mass was cooled and a polymer plug formed which was removed from the tube, then ground up on a centrifugal grinder. Melt temperature analysis was carried out using differential scanning calorimetry (DSC) on a 15 mg compressed pellet at a heating and cooling rate of 20° C. per minute on a Mettler DSC-30 low temperature cell with a Mettler TC10A thermal analysis processor (Mettler Instrument Corp., Hightstown, N.J.). Optical anisotropy of the copolyester melts can be determined by examination of the materials with the use of an optical microscope. The equipment used for determining the optical anisotropy of the copolyesters of the present invention included a TH 600 hot stage, (Linkham Scientific Instruments LTD, Surrey, England) and a Nikon Optiphot Microscope equipped with crossed polarizers and a 35 mm camera (Nikon Instrument Group, Nikon, Inc., Garden City, N.Y.). A thin film of the polymers shown in Tables I and II were optically anisotropic above their DSC-determined melting temperature when observed through a polarizing microscope. EXAMPLES I THROUGH V Preparation of Capolyesters from 4-Acetoxybenzoic Acid and 3-Benzoyl-4-acetoxybenzoic Acid The copolyesters of these examples were prepared using the general melt polymerization procedure as described above. The mole fraction of the 4-acetoxybenzoic acid (4-ABA), the remainder being 3-benzoyl-4-acetoxybenzoic acid, the glass transition temperature, Tg, and the melt temperature, Tm, are shown in Table I. TABLE I______________________________________Thermal Data for Copolyesters Prepared From3-Benzoyl-4-acetoxybenzoicAcid and 4-Acetoxybenzoic AcidMole Fraction4-ABA Tg (°C.) Tm (°C.)______________________________________0.35 110 1520.50 120 1520.65 112 1840.75 114 3060.85 -- 334______________________________________ EXAMPLES VI THROUGH VIII Preparation of Copolyesters from 4-Acetoxybenzoic Acid and 3-Phenoxy-4-acetoxybenzoic Acid The copolyesters of these examples were prepared using the general melt polymerization procedure as described above. The mole fraction of the 4-ABA, the remainder being 3-phenoxy-4-acetoxybenzoic acid, the glass transition temperature, Tg, and the melt temperature, Tm, are shown in Table II. TABLE II______________________________________Thermal Data for Copolyesters Prepared from 3-Phenoxy-4-acetoxybenzoic Acid and 4-Acetoxybenzoic AcidMole Fraction4-ABA Tg (°C.) Tm (°C.)______________________________________0.50 116 2610.60 132 3270.70 121 326______________________________________
The invention relates to a class of copolymers capable of forming an optically anisotropic melt comprising recurring structural units (a) independently each occurrence selected from the group consisting of Formula I; recurring structural units (b) independently each occurrence selected from the group consisting of Formulas II and III; and optionally recurring structural units (c) independently each occurrence selected from the group consisting of Formula IV: ##STR1## wherein R independently each occurrence is a chemically inert substituent.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "FIELD OF THE INVENTION The invention relates to a class of copolyesters which display optical anisotropy in the molten state and to the shaped articles, fibers and films obtained from the optically anisotropic melts.", "BACKGROUND OF THE INVENTION Liquid crystalline polymers (LCPs) are macromolecules possessing significant orientation in either the molten state or in concentrated solution.", "The state of their solution (lyotropic) or melt (thermotropic) is between the boundaries of solid crystals and isotropic liquids.", "In the solid state these highly ordered polymers display exceptional strength properties in the direction of orientation.", "By designing molecules containing only relatively inert chemical bonds, preparation of thermally and oxidatively stable high-performance materials is possible.", "A review of thermotropic LCPs can be found in Kwolek et al.", ", "Liquid Crystalline Polymers", "Encyclopedia of Polymer Science and Engineering "", "2nd Ed, Vol. 9, pp 23-55 (1987).", "Among those listed are polyesters.", "Many liquid crystalline polyesters display several of the desirable attributes of these compounds.", "Unfortunately, most have too high of a melt temperature for economical melt fabrication.", "There is a growing need in the thermoplastic engineering industries to provide for new and improved polyesters and copolyesters which possess a high degree of processability while concurrently exhibiting superior mechanical properties.", "SUMMARY OF THE INVENTION The invention concerns copolymers capable of forming an optically anisotropic melt comprising recurring structural units (a) independently each occurrence selected from the group consisting of Formula I;", "recurring structural units (b) independently each occurrence selected from the group consisting of Formulas II and III;", "and optionally recurring structural units (c) independently each occurrence selected from the group consisting of Formula IV: ##STR2## wherein R independently each occurrence is a chemically inert substituent.", "DETAILED DESCRIPTION Preferably, R is independently selected from the group consisting of hydrogen, halo, lower alkyl and methoxy.", "Most preferably, R is each occurrence hydrogen.", "Desirable molar percent ranges for these copolyesters are from 35 mole percent to 95 mole percent of independently recurring units of Formula I, from 5 mole percent to 50 mole percent of independently recurring units of Formulas II or from 5 mole percent to 65 mole percent of independently recurring units of Formulas III, or from 5 mole percent to 50 mole percent of independently recurring units of Formulas II, III and IV wherein the ratio of Formula II and III units to Formula IV units varies from 100:0 to 10:90.", "More preferable molar percent ranges for these copolyesters are from 50 mole percent to 90 mole percent of independently recurring units of Formula I, from 10 mole percent to 50 mole percent of independently recurring units of Formulas II or III, or from 10 mole percent to 50 mole percent of independently recurring units of Formulas II, III and IV wherein the ratio of Formula II and III units to Formula IV units varies from 100:0 to 10:90.", "The most preferred molar percent ranges are from 60 mole percent to 90 mole percent of independently recurring units of Formula I, from 10 mole percent to 40 mole percent of independently recurring units of Formulas II or III, or from 10 mole percent to 40 mole percent of independently recurring units of Formulas II, III and IV wherein the ratio of Formula II and III units to Formula IV units varies from 100:0 to 10:90.", "The copolymers may be formed by a variety of ester-forming techniques from difunctional organic compounds possessing functional groups which upon polycondensation form the requisite recurring units.", "For example, the functional groups of the organic aromatic compounds may independently contain carboxylic acid groups or acid halide groups and functional groups reactive therewith such as hydroxyl or acyloxy groups.", "In a preferred embodiment, the organic reactants comprise lower acyloxy and carboxylic acid functionality.", "For example, lower acyl esters of 4-hydroxybenzoic acid, 3-phenyl-4-hydroxybenzoic acid, 3-benzoyl-4-hydroxybenzoic acid, 3-phenoxy-4-hydroxybenzoic acid wherein the hydroxy group is esterified are more preferred as reactants.", "The lower acyl groups preferably have from 2 to 4 carbon atoms.", "Most preferably, the acetate esters are used.", "The organic compounds may be allowed to react under anhydrous conditions in an inert atmosphere via a melt acidolysis procedure, in a suitable solvent via a solution procedure, or in a heat exchange medium via a slurry polymerization as described in Calundann, U.S. Pat. No. 4,067,852.", "Additional suitable reaction conditions are described in Schaefgen, U.S. Pat. No. 4,118,372.", "The teachings of the foregoing U.S. patents are incorporated herein by reference.", "A preferable technique is the melt acidolysis technique.", "A catalyst may or may not be used in the polymerization process.", "If one is used, representative catalysts for use in the process include dialkyl tin oxides (e.g., dibutyl tin oxide), diaryl tin oxides, titanium dioxide, alkoxy titanium silicates, titanium alkoxides, Lewis acids, hydrogen halides (e.g., HCl), alkali and alkaline earth metal salts of carboxylic acids (e.g., sodium acetate).", "The quantity of catalyst utilized typically is from 0.001 to 1 weight percent based upon total reactant weight, and most commonly from 0.01 to 0.2 weight percent.", "In a preferred method of polymerization, a catalyst is not used.", "Liquid crystalline copolyester melts of this invention may be extruded into articles such as fibers which have outstanding strength and stiffness and will maintain their useful properties at elevated temperatures.", "Such fibers would be useful as tire cords, reinforcement in hoses, cables, conveyor belts or composite structures with matrixes prepared from other resinous materials.", "Articles may be films formed from the copolyesters which will have excellent solvent and chemical resistance.", "In addition, they should have low flammability and good electrical insulating properties.", "They would be useful as cable wrap, electric motor dielectric film and wire insulation.", "These copolyesters are useful for the manufacture of shaped articles such as those which are injection molded possessing high strength, stiffness, chemical resistance and low flammability.", "Conventional additives and processing aids can be added to the copolyester melts of the invention to improve the properties of articles made therefrom.", "Examples of additives are oxidation stabilizers;", "heat stabilizers;", "ultraviolet light (UV) stabilizers;", "lubricants;", "mold release agents;", "dyes and pigments;", "fibrous or powdered fillers and reinforcing agents;", "nucleating agents;", "and plasticizers.", "Examples of oxidation stabilizers and heat stabilizers are halides of metals of group I of the Periodic Table, used alone and used as a mixture with copper (I) halides or sterically hindered phenols in concentrations from 0.001 to 1 weight percent based on the weight of the copolyester composition.", "Examples of UV stabilizers are substituted resorcinols, salicylates, benzotriazoles, benzophenones and mixtures of these, which are added, for example, in amounts from 0.001 to 2 weight percent based on the weight of the copolyester composition.", "Dyes and pigments are used, for example, in amounts from 0.001 to 5 weight percent based on the weight of the copolyester composition.", "Examples are nigrosine, titanium dioxide, cadmium sulfide, phthalocyanine dyes, ultramarine blue and carbon black.", "Examples of fillers and reinforcing agents are carbon fibers, glass fibers, amorphous silica, calcium silicate, aluminum silicate, magnesium carbonate, kaolin, chalk, powdered quartz, mica and feldspar, which may be present in a concentration from 0.5 to 70 weight percent, based on the total weight of the filled material.", "Examples of nucleating agents are talc, calcium fluoride, sodium phenylphosphonate, alumina and finely divided polytetrafluoroethylene.", "Suitably, the nucleating agent may be present in an amount from 0.001 to 1 percent by weight.", "Plasticizers, such as phthalates, hydrocarbon oils and sulfonamides can be included in an amount of from 0.0001 to 20 weight percent, based on the weight of the composition.", "Also included in the composition of the invention, in addition to or in partial replacement of the reactants of Formulas I, II, III or IV are amounts of other aromatic polymerizable units whose presence do not interfere with the excellent mechanical properties of these copolyesters.", "Examples of such aromatic units comprising these additional repeating units are 2-hydroxy-6-naphthoic acid, 4-hydroxy-4'-carboxybiphenyl and 3-hydroxybenzoic acid.", "Preparation of 4-Acetoxybenzoic Acid An amount of 4-hydroxybenzoic acid (92.1 grams (g), 0.67 mole) was dissolved in a solution of sodium hydroxide (NaOH) (53.4 g, 1.33 moles) and 1.33 liters (L) of water in a 4 L beaker.", "The solution was stirred and cooled to a temperature of 0° C. by adding crushed ice, then acetic anhydride (102.1 g, 1.00 mole) was added.", "The temperature was maintained at -2° C. for 1 hour by adding one kilogram (kg) of crushed ice.", "A solution of concentrated hydrochloric acid (HCl) (144.7 g, 1.42 moles) in 267 milliliters (ml) of water was added.", "The slurry was stirred briefly and filtered.", "The product was washed twice by stirring it with 2 L portions of fresh water then filtered and dried in a vacuum oven at 80° C. for 16 hours.", "After recrystallization from methyl isobutyl ketone, the product consisted of 111 g of white crystals with a melting point (m.p.) of 192° C. to 192.5° C. Preparation of 3-Benzoyl-4-Acetoxybenzoic Acid A solution of benzoyl chloride (24.2 g, 0.30 mole) in 25 ml of cyclohexane was added over 5 minutes to a refluxing mixture of p-methylanisole (44.0 g, 0.36 mole), anhydrous zinc chloride (0.41 g, 3 millimoles (mmol)) and 75 ml of cyclohexane.", "The mixture was refluxed under nitrogen for 23 hours.", "After 2.5 hours, an additional 0.41 g of anhydrous zinc chloride was added.", "The resulting black solution was washed two times with 100 ml of 0.5N sodium hydroxide (NaOH), then with 1N hydrochloric acid (HCl), then with a 5 weight percent solution of aqueous sodium bicarbonate (NaHCO 3 ) and water.", "The clear yellow solution was dried with magnesium sulfate (MgSO 4 ), then the solvent was removed and the viscous yellow oil which remained was vacuum distilled through a six inch Vigreaux column.", "The product, 2-methoxy-5-methylbenzophenone was collected as a clear colorless oil which slowly crystallized.", "An amount of 2-methoxy-5-methylbenzophenone (14.2 g, 62.7 mmol) and a solution of potassium permanganate (KMnO 4 ) (24.8 g, 157 mmol) in 300 ml of water were stirred under reflux (102° C.) for one hour.", "The reaction mixture was cooled to 45° C. and sodium hydrogen sulfite (NaHSO 3 ) (45 g, 0.44 mole) was dissolved in the reaction mixture.", "Slowly 50 g of concentrated HCl was added.", "The white solid which was produced was taken up twice in 250 ml of ether.", "The combined organic phase was extracted twice with 150 ml of 0.67N NaOH.", "The ether phase was dried with MgSO 4 and the ether was removed.", "There remained 7.49 g of unreacted starting material.", "The combined basic extracts were acidified with concentrated HCl and extracted twice with 250 ml of ether.", "The ether extracts were dried with MgSO 4 and concentrated to produce 3-benzoyl-4-methoxybenzoic acid.", "The product was recrystallized from a mixture of 100 ml of ethanol and 200 ml of water.", "A solution of 3-benzoyl-4-methoxybenzoic acid (10.23 g, 40 mole), 100 ml of 48 weight percent aqueous hydrobromic acid (HBr) (149 g, 0.88 mole) and 200 ml of acetic acid was refluxed under nitrogen.", "After five hours, a white solid began to separate.", "After 22 hours, the slurry was cooled in ice and filtered.", "The white solid which was collected was washed with water and dried in a vacuum oven.", "There remained white granular 3-benzoyl-4-hydroxybenzoic acid.", "Acetic anhydride (10.5 g, 0.103 mmol) was added to a solution of 3-benzoyl-4-hydroxybenzoic acid (12.5 g, 51.6 mole) and NaOH (4.33 g, 0.108 mmol) in 250 ml of water under nitrogen.", "The clear colorless solution was stirred at 8° C. for one hour.", "The product separated initially as a colorless oil which soon crystallized to a white solid.", "The slurry was made strongly acidic by adding concentrated HCl, and was extracted with ether.", "The ether extract was washed with water, and dried with MgSO 4 and evaporated to dryness providing crude acetoxy acid.", "The crude product was recrystallized from a mixture of 200 ml of toluene and 150 ml of cyclohexane to give 3-benzoyl-4-acetoxybenzoic acid with a m.p. of 162.5° C. to 163° C. Preparation of 3-Phenyl-4-Acetoxybenzoic Acid A solution of 2-hydroxybiphenyl (51.2 g, 0.300 mole), 50 weight percent aqueous NaOH solution (28.6 g, 0.360 mole) and 120 ml of deionized water were added to a one-liter, three-necked, round-bottom flask equipped with a cold water condenser, nitrogen inlet, thermometer, and an air-powered paddle stirrer.", "The solution was stirred under nitrogen until homogeneous, then 175 ml of a methylene chloride solution of bromoethane (65.3 g, 0.600 mole) and tetrabutylammonium bromide (9.70 g, 0.030 mole) was added with vigorous stirring.", "The reaction mixture was stirred at room temperature for 22 hours.", "The mixture was transferred to a one-liter separatory funnel and the organic layer was decanted and saved.", "Before discarding the aqueous layer, it was extracted with 25 ml of methylene chloride.", "The methylene chloride extract was added to the organic reaction solution which was added to a bottle containing 100 ml of 10 weight percent aqueous NaOH solution.", "The mixture was shaken vigorously for 0.5 hours on a mechanical shaker.", "The separated aqueous layer was discarded.", "The organic layer was washed twice with 50 ml of 1N HCl followed by a 50 ml deionized water wash.", "The organic solution was stored over anhydrous MgSO 4 for several hours then the solvent was removed by rotary evaporation to provide a salmon-colored liquid.", "The sides of the flask were scraped with a glass stirring rod inducing crystallization of the product, 2-ethoxybiphenyl.", "A solution of 2-ethoxybiphenyl (19.8 g, 0.100 mole) and 100 ml of carbon disulfide were added to a 250-ml, three-necked, round-bottom reaction flask equipped with a cold water condenser, nitrogen inlet, thermometer and polytetrafluoroethylene-coated magnetic stir bar.", "The solution was maintained under nitrogen and brought to a mild reflux at approximately 46° C. Anhydrous aluminum chloride (AlCl 3 ) (13.8 g, 0.104 mole) was added slowly to the refluxing solution via a dropping funnel.", "A green, heterogeneous mixture was formed.", "Approximately 60 ml of a carbon disulfide solution containing acetyl chloride (8.07 g, 0.103 mole) was added dropwise to the refluxing reaction solution over 100 minutes.", "The reaction solution was refluxed for an additional hour after the last acetyl chloride addition, then cooled to room temperature.", "The reaction solution was poured slowly into a cold HCl solution and stirred.", "The contents were then transferred to a 500 ml separatory funnel, shaken, and the separated organic layer was stored over anhydrous MgSO 4 .", "Before discarding, the aqueous layer was washed with 25 ml of layer.", "The dried organic layer was filtered and the volatiles were rotary evaporated off leaving a tan solid which was dried under vacuum at 60° C. for two hours yielding a crude product.", "The solid was recrystallized from hexane to give 3-phenyl-4-ethoxyacetophenone.", "A mixture of 3-phenyl-4-ethoxyacetophenone (32.2 g, 0.134 mole) and 250 ml of p-dioxane was added to a one-liter, three-necked, round-bottom flask equipped with a pressure equalizing dropping funnel, thermometer and a polytetrafluoroethylene-coated magnetic stir bar.", "The mixture was stirred to dissolve the solid, then 480 mi of sodium hypobromite solution (0.53 mole), prepared by dissolving NaOH (126 g, 3.15 moles) in 600 ml of deionized water, followed by dropwise addition of 45 ml of bromine (0.87 mole) over a 60 minute time period, was added.", "The solution temperature rose from 22° C. to 48° C. during the addition.", "The reaction solution was stirred an additional 15 minutes after the last of the NaOBr addition, then a solution of 40 weight percent aqueous NaHSO 3 (41.9 g, 1.61 moles) was added to remove any remaining NaOBr.", "The solution was then immersed in an ice bath and acidified to a pH of 2 with concentrated HCl.", "A light yellow solid precipitated upon acidification.", "The solid was filtered, recrystallized from a dioxane and water mixture, filtered and dried under vacuum at 60° C. overnight to yield a light yellow solid of 3-phenyl-4-ethoxybenzoic acid.", "A solution of 3-phenyl-4-ethoxybenzoic acid (26.6 g, 0.110 mole) and 550 ml of acetic acid was added to a one-liter, three-necked, round-bottom flask equipped with a 250 ml pressure equalizing dropping funnel, thermometer, cold water condenser, nitrogen inlet adapter and a polytetrafluoroethylene-coated magnetic stir bar.", "The flask was purged with nitrogen and the solution was brought to reflux.", "Approximately 125 ml of a 48 weight percent solution of HBr was added dropwise over fifteen minutes to the refluxing solution.", "The solution was refluxed for 30 hours.", "Without cooling, the solvent was rotary evaporated off leaving a slurry of a pinkish solid.", "The slurry was poured into one liter of deionized water and the mixture was stirred for one hour and filtered.", "The filter cake was dried in an 80° C. vacuum oven for three hours yielding 3-phenyl-4-hydroxybenzoic acid.", "A solution of 3-phenyl-4-hydroxybenzoic acid (131.1 g, 0.061 mole) and a 50 weight percent aqueous solution of NaOH (10.5 g, 0.131 mole) in 350 ml of deionized water was added to a 500 ml, three-necked, round-bottom flask equipped with a thermometer and a polytetrafluoroethylene-coated magnetic stir bar.", "The solution was stirred to homogeneity and then immersed in an ice water bath.", "With the solution temperature at 10° C., acetic anhydride (12.7 g, 0.124 mole) was added rapidly with stirring.", "Immediately, a white precipitate began to form.", "The reaction mixture was stirred for one hour at 10° C., then neutralized with concentrated HCl.", "The precipitate was filtered, washed in 500 ml of deionized water for one hour, filtered, and dried in an 80° C. vacuum oven for three hours yielding an off-white solid.", "The solid was recrystallized from a toluene and hexane mixture to give a fluffy white solid, 3-phenyl-4-acetoxybenzoic acid with a m.p. of 185° C. to 187° C. Preparation of 3-Phenoxy-4-Acetoxybenzoic Acid A solution of bromine (79.9 g, 0.500 mole) in 100 ml of carbon tetrachloride (CCl 4 ) was slowly added over a 15 minute period to a stirred solution of 4-methylanisole (61.1 g, 0.500 mole) in 400 ml Of CCl 4 at 25° C. in the dark.", "Gaseous HBr evolved.", "Slight cooling was used to keep the temperature at 25° C. to 30° C. After 1.5 hours, the evolution of HBr stopped and the deep red solution was allowed to stand in the dark overnight.", "The reaction mass was washed with aqueous solutions of NaHSO 3 and NaHCO 3 , then with water.", "The solution was dried, concentrated and vacuum distilled through a 30 cm column packed with ceramic saddles.", "The fraction boiling between 102° C. and 105° C. at 8 mm Hg was collected.", "The product, 2-bromo-4-methylanisole was a clear colorless liquid.", "A stirred mixture of phenol (20.7 g, 0.220 mole) and powdered KOH (12.3 g, 0.220 mole) was slowly heated to 167° C. under nitrogen.", "At 120° C., the reaction mass became a clear colorless liquid.", "The pressure was slowly reduced.", "At 150 mm Hg, water began to distill.", "When most of the water had been removed, the reaction mass solidified.", "The white solid was held at 167° C. and 1 mm Hg for 30 minutes to remove the last traces of water, then cooled to room temperature.", "Electrolytic copper dust (70 milligrams (mg), 0.0011 gram-atoms), 2-bromo-4-methylanisole (40.4 g, 0.200 mole) and phenol (10.4 g, 0.110 mole) were added, then the flask was lowered into an oil bath that had been preheated to 200° C. All the solid dissolved.", "The dark red liquid was stirred under nitrogen at 200° C. for 3.5 hours.", "The reaction mass was cooled, diluted with 500 ml of ether, and washed three times with 100 ml portions of 1N NaOH, then with 1N HCl, then with 5 weight percent aqueous NaHCO 3 solution and with water.", "The solution was filtered to remove a few droplets of undissolved black tar, then cooled in dry ice.", "The product, 2-phenoxy-4-methylanisole separated as an oil which slowly crystallized.", "A solution of 2-phenoxy-4-methylanisole (26.9 g, 0.126 mole), KMnO 4 (48.8 g, 0.315 mole), 240 ml of deionized water and 480 ml of pyridine was added to a two-liter, one-necked, round-bottom flask equipped with a reflux condenser and a polytetrafluoroethylene-coated magnetic stir bar.", "The solution was brought to reflux while stirring for 1.5 hours at which point the solution was brown and the heating mantle was removed.", "The mixture was brought to near dryness on a rotary evaporator.", "Approximately 250 ml of deionized water was added to the flask with NaHSO 3 (41.6 g, 0.400 mole).", "Concentrated HCl was added slowly to the aqueous solution resulting in the precipitation of an off-white solid.", "The solid was filtered and washed in 600 ml of deionized water for one hour, refiltered and dissolved in 250 ml of deionized water with NaOH (0.15 mole).", "The aqueous solution was extracted with 125 ml of ether to remove unreacted starting material.", "The aqueous layer was added dropwise into a rapidly stirred dilute acid solution of HCl (0.2 mole) in 600 mi of water, resulting in the precipitation of a white, finely divided solid.", "The white solid was collected and dried at 100° C. under vacuum for four hours yielding an off-white solid that was 3-phenoxy-4-methoxybenzoic acid.", "A solution of 3-phenoxy-4-methoxybenzoic acid (17.0 g, 0.07 mole), a 48 weight percent aqueous solution of HBr (165 ml, 1.39 mole) and 350 ml of glacial acetic acid was added to a 1-liter, one-necked, round-bottom flask equipped with a reflux condenser, nitrogen inlet adapter and a polytetrafluoroethylene-coated magnetic stir bar.", "The solution was heated under nitrogen and refluxed for 16 hours.", "While still hot, the flask was transferred to a rotary evaporator and the volatiles were removed leaving a salmon-colored solid which was added to 200 ml of 1.25N NaOH solution (0.25 mole).", "Most of the solid dissolved.", "The insoluble portion was filtered off.", "The remaining aqueous base solution was added dropwise to a stirred aqueous HCl solution (0.25 mole in 400 ml deionized water) resulting in the precipitation of a salmon-colored solid.", "The solid was washed in 300 ml of deionized water for 1 hour, filtered, dried at room temperature overnight, and dried under vacuum at 100° C. for 1 hour yielding 3-phenoxy-4-hydroxybenzoic acid.", "A solution of 3-phenoxy-4-hydroxybenzoic acid (13.9 g, 0.0560 mole), 200 ml of deionized water, and NaOH (11.2 g of 50 weight percent aqueous solution, 0.140 mole) was added to a 500-ml conical flask equipped with a thermometer and a polytetrafluoroethylene-coated magnetic stir bar.", "The reaction flask was immersed in an ice bath and stirred.", "Acetic anhydride (12.2 g, 0.120 mole) was added rapidly to the stirred solution causing a temperature increase from 7° C. to 12° C. Approximately one minute after the acetic anhydride addition, a precipitate began to appear.", "The solution was stirred for one hour at 5° C. to 7° C. and was neutralized with concentrated HCl (15 g, 0.15 mole) causing further precipitation.", "The off-white precipitate was filtered and washed with 200 ml of deionized water for one hour, refiltered and dried at 80° C. under vacuum for two hours yielding an off-white solid.", "This product was recrystallized from toluene, filtered and dried one hour under vacuum to yield an off-white solid which was 3-phenoxy-4-acetoxybenzoic acid with a m.p. of 181° C. to 183° C. Having described the invention, the following examples are provided as further illustrative and are not to be construed as limiting.", "General Melt Polymerization Procedure Small-scale melt polymerizations were carried out in 15 mm internal diameter (I.D.) polymerization tubes for 1 to 3 g quantities and in 24 mm I.D. polymerization tubes for 6 g quantities.", "The tubes were fitted with a head equipped with an adjustable capillary tube, a combined distillate delivery tube and air condenser, a receiver and a combined nitrogen inlet and vacuum port.", "The lower portion of the polymerization tube was heated in a small, vertical hot air oven.", "After the reactants were added to the polymerization tube, it was evacuated and refilled with nitrogen three times, then heated to 260° C. After the reactants had melted to form a liquid reaction mass, a capillary tube was lowered below the liquid surface and the nitrogen flow was adjusted to show a slow stream of bubbles passing through the liquid.", "The polymerization was held at 260° C. until about one half of the theoretical amount of acetic acid had been collected.", "At this point, the temperature was increased and the pressure was reduced at a rate sufficient to keep the rate of acetic acid evolution steady.", "A typical heating schedule was 1 hour at 260° C., 1 hour at 300° C. and 1 hour at 320° C. The liquid was then put under vacuum of 1 mm Hg at 340° C. for 30 minutes.", "The viscosity of the reaction mass was periodically measured by moving the capillary through the liquid.", "The capillary was raised to a position about 1 cm above the reaction mass before the mass became solid or extremely viscous.", "The polymerization was stopped when approximately all the theoretically calculated amount of acetic acid had been collected.", "The reaction mass was cooled and a polymer plug formed which was removed from the tube, then ground up on a centrifugal grinder.", "Melt temperature analysis was carried out using differential scanning calorimetry (DSC) on a 15 mg compressed pellet at a heating and cooling rate of 20° C. per minute on a Mettler DSC-30 low temperature cell with a Mettler TC10A thermal analysis processor (Mettler Instrument Corp.", ", Hightstown, N.J.).", "Optical anisotropy of the copolyester melts can be determined by examination of the materials with the use of an optical microscope.", "The equipment used for determining the optical anisotropy of the copolyesters of the present invention included a TH 600 hot stage, (Linkham Scientific Instruments LTD, Surrey, England) and a Nikon Optiphot Microscope equipped with crossed polarizers and a 35 mm camera (Nikon Instrument Group, Nikon, Inc., Garden City, N.Y.).", "A thin film of the polymers shown in Tables I and II were optically anisotropic above their DSC-determined melting temperature when observed through a polarizing microscope.", "EXAMPLES I THROUGH V Preparation of Capolyesters from 4-Acetoxybenzoic Acid and 3-Benzoyl-4-acetoxybenzoic Acid The copolyesters of these examples were prepared using the general melt polymerization procedure as described above.", "The mole fraction of the 4-acetoxybenzoic acid (4-ABA), the remainder being 3-benzoyl-4-acetoxybenzoic acid, the glass transition temperature, Tg, and the melt temperature, Tm, are shown in Table I. TABLE I______________________________________Thermal Data for Copolyesters Prepared From3-Benzoyl-4-acetoxybenzoicAcid and 4-Acetoxybenzoic AcidMole Fraction4-ABA Tg (°C.) Tm (°C.)______________________________________0.35 110 1520.50 120 1520.65 112 1840.75 114 3060.85 -- 334______________________________________ EXAMPLES VI THROUGH VIII Preparation of Copolyesters from 4-Acetoxybenzoic Acid and 3-Phenoxy-4-acetoxybenzoic Acid The copolyesters of these examples were prepared using the general melt polymerization procedure as described above.", "The mole fraction of the 4-ABA, the remainder being 3-phenoxy-4-acetoxybenzoic acid, the glass transition temperature, Tg, and the melt temperature, Tm, are shown in Table II.", "TABLE II______________________________________Thermal Data for Copolyesters Prepared from 3-Phenoxy-4-acetoxybenzoic Acid and 4-Acetoxybenzoic AcidMole Fraction4-ABA Tg (°C.) Tm (°C.)______________________________________0.50 116 2610.60 132 3270.70 121 326______________________________________" ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as an electrophotographic copier, a printer, a facsimile device, and a compound device thereof, and more particularly to a developer replenishing device suitable for use in this image forming apparatus. 2. Description of the Related Art In an electrophotographic image forming apparatus, an image is typically created by forming a toner image using a so-called developer containing a toner and a carrier. The toner is steadily consumed as image formation progresses, and therefore a toner storage container serving as a toner cartridge filled with toner is generally used, and when all of the toner in the toner storage container has been consumed, new toner is supplied by replacing the toner storage container with a new toner storage container. Since toner is a powder, it is important to discharge the toner such that as little toner as possible remains in the toner storage container. Conventional methods for conveying toner from the interior of the container to a container outlet portion include a method of providing a screw known as an auger in the interior of the container and conveying the toner in a single direction by rotating the screw, a method of providing a spiral projection known as a screw bottle on the inner surface of a cylindrical portion of a tubular container and rotating the container such that the toner is conveyed little by little to an outlet portion of the container, and so on. The present inventor has proposed a method of discharging toner from a toner storage container by applying acceleration to the toner storage container through an asymmetric reciprocating motion such that the toner in the container is moved in a single direction by inertia and discharged through a discharge port provided in the downward direction of the container. In the toner conveyance method employing an auger, a member must be provided in the interior of the container and rotated, and therefore the structure of the container becomes complicated. In the toner conveyance method employing a screw bottle, no member need be provided in the interior of the container, and therefore the structure of the container is simple, but since the container is rotated, the container must be formed with a cylindrical main body and provided with an outlet in one end surface (the shape of a normal bottle laid on its side). Hence, in comparison with a rectangular parallelepiped-shaped container, the amount of toner that can be stored in the container is small, the container is not easy to hold and may slip out of the hand during replacement, and so on. Meanwhile, with the method of applying a reciprocating motion (in the lateral direction) to the container to move the toner inside the container such that the toner is discharged through a discharge port provided in the lower side of the container (to be referred to hereafter as a reciprocation method) a simple container shape such as a rectangular parallelepiped that can hold a large amount of toner (that has little dead space) may be employed, and since there is no need to provide a conveyor member inside the container, a low-cost, compact replenishing device can be realized. Moreover, a bag-shaped container constituted by a flexible sheet may be used, enabling savings in natural resources and costs. However, a reciprocation type replenishing device is greatly disadvantaged in that the resultant vibration causes abnormal images (banding). Hence, to cancel out the effect of vibration generated during reciprocation of the container on the main body, a method of providing a movable stopper and causing the container and stopper to collide at opposite phase speeds has been proposed. However, even slight vibration affects image formation, and therefore a replenishment method in which vibration is reduced to the greatest extent possible is required. Meanwhile, during image formation, residual toner is generated following transfer, and conventionally, this residual toner is recovered in a recovery bottle. A method of provided the container with a recovery chamber in advance and recovering the residual toner in the container has also been proposed, but when this method is employed, the constitution of a residual toner moving device and the capacity of the container decrease, and the cost of the container rises due to its complexity. It is therefore difficult to incorporate this method into an actual product. Technologies relating to the present invention are also disclosed in, e.g., Japanese Unexamined Patent Application Publication 2003-098813, Japanese Unexamined Patent Application Publication 2005-292300, Japanese Unexamined Patent Application Publication S63-010424, and Japanese Unexamined Patent Application Publication 2002-148924. SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner replenishing device for an image forming apparatus which can solve the conventional problems described above by realizing a container and a device having a high toner volumetric efficiency and a low cost, suppressing vibration during toner replenishment to a minimum, and storing recovered toner without impairing the volumetric efficiency of unused toner. In an aspect of the present invention, a developer replenishing device is provided with a developer container storing a developer used in an image forming apparatus, and replenishes a developing device of the image forming apparatus with the developer in the developer container. The developer container is rectangular in a horizontal direction, and comprises an outside container storing unused developer and a deformable inside container enveloped by the outside container. The developer replenishing device comprises a developer discharge port, provided in the outside container, for discharging the developer from the interior of the outside container; an air supply port for introducing air into the inside container; and air supplying means for supplying air to the air supply port. In another aspect of the present invention, a developer container stores a developer used in an image forming apparatus. The developer container is rectangular in a horizontal direction, and comprises an outside container storing unused developer and a deformable inside container enveloped by the outside container, and further comprises a developer discharge port, provided in the outside container, for discharging the developer from the interior of the outside container; and an air supply port for introducing air into the inside container. In another aspect of the present invention, an image forming apparatus uses a developer replenishing device. The developer replenishing device is provided with a developer container storing a developer used in the image forming apparatus, and replenishes a developing device of the image forming apparatus with the developer in the developer container. The developer container is rectangular in a horizontal direction, and comprises an outside container storing unused developer and a deformable inside container enveloped by the outside container. The developer replenishing device comprises a developer discharge port, provided in the outside container, for discharging the developer from the interior of the outside container; an air supply port for introducing air into the inside container; and air supplying means for supplying air to the air supply port. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken with the accompanying drawings, in which: FIG. 1 is a view showing the overall constitution of an image forming apparatus (printer) to which the present invention is applied; FIG. 2 is a view showing the overall constitution of an electrophotographic image forming apparatus in which an embodiment of a developer replenishing device according to the present invention is used in a toner replenishment portion; FIG. 3 is a view showing a state in which a discharge outlet shutter is attached to a toner container shown in FIG. 2 ; FIG. 4 is an exterior perspective view of the toner container seen from below; FIGS. 5 to 7 are view showing a process of supplying toner from the toner container; FIG. 8 is a view showing the overall constitution of an image forming apparatus in which a second embodiment of the developer replenishing device according to the present invention is used in a toner replenishment portion; FIG. 9 is an exterior perspective view of a toner container shown in FIG. 8 ; FIG. 10 is a view showing one bag container (an outside container or an inside container) of the toner container before being formed into a bag shape; FIG. 11 is a sectional view of a sheet adhered to the bag container; FIG. 12 is a view showing that the bag container has a duplex structure consisting of the inside container and the outside container; FIG. 13 is a view showing a state in which only the outside container is expanded from the state shown in FIG. 12 ; and FIG. 14 is an exterior perspective view showing the constitution of a toner container according to a third embodiment of the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below on the basis of the attached drawings. First Embodiment FIG. 1 shows the overall constitution of an image forming apparatus (printer) to which this embodiment is applied. As shown in the drawing, in this image forming apparatus, four toner containers 131 Y, 131 M, 131 C, 131 K corresponding to four colors (yellow, magenta, cyan, black) are disposed detachably (replaceably) in a toner container storage portion above an image forming apparatus main body 100 . An intermediate transfer unit 130 is disposed beneath the toner container storage portion, and image creating portions 1 Y, 1 M, 1 C, 1 K corresponding to the four colors (yellow, magenta, cyan, black) are arranged in series so as to face an intermediate transfer belt 180 of the intermediate transfer unit 130 . For example, the image creating portion 1 Y corresponding to yellow is constituted by a photosensitive drum 2 Y, and a charging portion, a developing device (development portion), a cleaning portion, a neutralizing portion (not shown), and so on, which are arranged around the photosensitive drum 2 Y. Image creating processes (a charging process, an exposure process, a development process, a transfer process and a cleaning process) are implemented on the photosensitive drum 2 Y to form a yellow image on the photosensitive drum 2 Y. Apart from the color of the used toner, the other three image creating portions 1 M, 1 C, 1 K have a substantially identical constitution to the image creating portion 1 Y corresponding to yellow, and respectively form images in the corresponding toner colors. Accordingly, in the following description, the symbols Y, M, C, K denoting the colors will be omitted except where necessary. The photosensitive drum 2 is driven to rotate in the clockwise direction of the drawing by a drive motor, not shown in the drawing. Then, in the position of the charging portion, the surface of the photosensitive drum 2 is uniformly charged (charging process). An electrostatic latent image corresponding to yellow is then formed on the surface of the photosensitive drum 2 by exposing and scanning the surface of the photosensitive drum 2 with a laser beam emitted from an exposing device 120 in an irradiation position (exposure process). Next, the electrostatic latent image on the surface of the photosensitive drum 2 is developed in a position facing the developing device to form a yellow toner image (development process). The toner image on the photosensitive drum 2 is then transferred onto the intermediate transfer belt 180 in a position facing the intermediate transfer belt 180 and a primary transfer bias rollers 140 Y, 140 M, 140 C, 140 K (primary transfer process). At this time, a small amount of non-transferred toner remains on the photosensitive drum 2 . However, the non-transferred toner remaining on the photosensitive drum 2 is then mechanically recovered by a cleaning blade in a position facing the cleaning portion (cleaning process). Finally, the remaining potential on the photosensitive drum 2 is removed in a position facing the neutralizing portion, not shown in the drawing, whereupon the series of image creating processes executed on the photosensitive drum 2 is terminated. The other image creating portions 1 M, 1 C, 1 K perform the image creating processes described above in a similar manner to the yellow image creating portion 1 Y, whereupon the toner image of each color formed on the respective photosensitive drums 2 are superposed onto the intermediate transfer belt 180 such that a color image is formed on the intermediate transfer belt 180 . The intermediate transfer unit 130 is constituted by the intermediate transfer belt 180 , four primary transfer bias rollers, a secondary transfer backup roller 180 a, a cleaning backup roller, a tension roller 180 c, an intermediate transfer cleaning portion 190 , and so on. The intermediate transfer belt 180 is stretched and supported by the two rollers 180 a, 180 c, and is moved in the direction of the arrow in FIG. 1 when one of the rollers is driven to rotate. The four primary transfer bias rollers 140 Y, 140 M, 140 C, 140 K sandwich the intermediate transfer belt 180 on the opposite side of the photosensitive drum 2 to form a primary transfer nip. A transfer bias having a reverse polarity to the polarity of the toner is applied to the primary transfer bias roller 140 . The intermediate transfer belt 180 travels in the direction of the arrow in the drawing, thereby passing through the primary transfer nip of each primary transfer bias roller 140 in sequence, and thus the toner images of the four colors on the respective photosensitive drums 2 are subjected to primary transfer so as to be superposed onto the intermediate transfer belt 180 . Next, in the position of a secondary transfer nip formed by sandwiching the intermediate transfer belt 180 between the secondary transfer backup roller 180 a and a secondary transfer roller 141 , the color toner image formed on the intermediate transfer belt 180 is transferred onto a copying subject material P such as transfer paper that has been conveyed to the position of the secondary transfer nip. At this time, non-transferred toner that has not been transferred onto the copying subject material P remains on the intermediate transfer belt 180 , and therefore the non-transferred toner on the intermediate transfer belt 180 is recovered in the position of the intermediate transfer cleaning portion 190 , whereupon the series of transfer processes executed on the intermediate transfer belt 180 is terminated. Note that the copying subject material P conveyed to the position of the secondary transfer nip is conveyed from a tray 160 disposed beneath the apparatus main body via a feed roller 160 a, a registration roller pair 151 , and so on. A plurality of sheets of the copying subject material P such as transfer paper are stacked and stored on the tray 160 , and by driving the feed roller 160 a to rotate in the counter-clockwise direction of FIG. 1 , the uppermost sheet of the copying subject material P is fed between the rollers of the registration roller pair 151 . The copying subject material P conveyed to the registration roller pair 151 is halted temporarily in the position of a roller nip formed when rotation of the registration roller pair 151 is halted, and at a timing corresponding to the color image on the intermediate transfer belt 180 , the registration roller pair 151 are driven to rotate such that the copying subject material P is conveyed toward the secondary transfer nip. Once the color image has been transferred onto the copying subject material P in the position of the secondary transfer nip, the copying subject material P is conveyed to a fixing portion 170 , where heat and pressure are supplied from a fixing roller, a pressure roller, and so on to fix the color image transferred onto the surface. The copying subject material P is then discharged to the exterior of the apparatus via a discharge roller pair, and stacked. At this point, the series of image forming processes executed by the image forming apparatus is terminated. FIG. 2 shows an example of an electrophotographic image forming apparatus using a developer replenishing device according to this embodiment in a toner replenishing portion. In the drawing, the reference numeral 2 denotes a photosensitive body. Similarly to a typical electrophotographic process, a uniform charge is applied to the photosensitive body 2 by a charging device 3 , and then the photosensitive body 2 receives exposure light L corresponding to an image formed by an exposing device, not shown in the drawing, whereby an electrostatic latent image is formed thereon. The reference numeral 4 in the drawing denotes a developing device, which is a unit for forming a toner image by developing the electrostatic latent image using toner. The reference numeral 50 in the drawing is a conventional, well-known cleaning device for recovering residual toner from the photosensitive body 2 following transfer and transferring the toner to a recovery bottle, not shown in the drawing. In this apparatus, the toner image formed on the photosensitive body 2 is transferred onto a sheet of transfer paper fed from a feeding device, not shown in the drawing, by a transfer device, not shown in the drawing (or via an intermediate transfer belt). The toner image is then fixed onto the transfer paper by a fixing device, not shown in the drawing, whereupon the image is output. The reference numeral 5 in the drawing denotes a toner container having a substantially square or substantially rectangular front surface cross-section and formed so as to extend horizontally in the lengthwise direction. The toner container 5 is attached from the right side to the left side in the drawing. Assuming that the right side of the drawing is the front surface of the apparatus main body, for example, the toner container 5 is inserted toward the rear side from the main body front surface. A toner replenishing device 10 for replenishing toner consumed during image formation is provided in series with the developing device 4 . The developing device 4 shown in the drawing is a so-called two-component developing device that stores a developer 8 formed by mixing together a toner and a carrier. The reference symbols 5 a and 6 a in the drawing denote two conveyance screws for agitating the developer. Further, the reference numeral 7 in the drawing denotes a development roller having magnets of different polarities fixed to the interior thereof and a sleeve that rotates on the outer periphery thereof. The development roller 7 creates a toner image by developing a latent image while holding the agitated developer on the sleeve of the roller surface with the magnets. The reference numeral 9 in the drawing denotes a doctor blade, which is used to restrict the developer on the development roller to a fixed height. In the developing device 4 , toner is consumed steadily as image formation progresses. The developing device 4 comprises a toner concentration sensor 34 that constantly detects the toner concentration of the developer 8 . When the toner concentration of the developer 8 falls below a predetermined value, control is performed to transmit an operation signal to the toner replenishing device 10 . The toner replenishing device 10 serves as a part for replenishing toner. An outside container 12 and an inside container 13 constituting the toner container 11 are flexible, bag-shaped toner storage members formed by one or more layers of a flexible sheet made of resin, such as polyethylene or nylon, or paper and having a thickness of approximately 50 to 200 μm. The reference numeral 14 in the drawing denotes a discharge mouthpiece portion provided with a toner discharge port 14 a, which is constituted by a hard material such as resin and welded or adhered to the outside container 12 as shown in the drawing. When the same material is used for the flexible members and the rigid member, the materials do not have to be separated when the container is reused, and therefore an improvement in recycling efficiency is achieved. New toner T is stored in the outside container 12 , and when the toner T is consumed, the whole container is exchanged for a new one. The reference numeral 15 in the drawing denotes a rigid base plate made of resin or the like, which is fixed detachably to the flexible container through fitting, adhesion, or the like so that the container can be attached easily to the machine main body. The used toner container 11 may be sent back to the maker from the user for recycling and reuse. In this case, the flexible container alone may be incinerated and used as thermal energy, and the hard members such as the base plate and mouthpiece may be reused. Incinerating members that use few natural resources and reusing components that use a lot of natural resources in this manner is an extremely effective method of recycling. The reference numeral 22 in the drawing denotes a supply mouthpiece comprising a supply port for supplying air to the inside container 13 . The supply mouthpiece 22 is constituted by a hard material such as resin, and is adhered to the inside container 13 and outside container 12 as shown in the drawing. Similarly to the discharge mouthpiece, when the supply mouthpiece 22 uses an identical material to the flexible members, an improvement in recycling efficiency is achieved. As described above, when the toner container 11 is attached in the direction of an arrow A in the drawing by a guide member, not shown in the drawing, provided on the replenishing device main body, a discharge nozzle 16 is attached to the discharge mouthpiece 14 while pushing a discharge port shutter 17 toward the right side of the drawing. The discharge mouthpiece is provided with seals 15 a , 15 b which come into close contact with the discharge nozzle 16 and the shutter 17 , respectively, such that a toner discharge path extending from the interior of the container to the discharge port 14 a , a discharge tube 25 , and a powder pump 40 is hermetically sealed from the outside. Thus, the powder pump 40 becomes capable of pumping the toner T through suction pressure, as will be described below. A member 18 is biased upwardly by a spring 19 . FIG. 3 shows a state in which the discharge port shutter 17 is attached to the toner container 11 of FIG. 1 (a state prior to insertion of the shutter or when the container has been detached from the main body). When attaching the toner container 11 , a supply nozzle 24 is simultaneously inserted into a slit provided in a supply port seal 23 formed from a sponge material and attached to the supply mouthpiece 22 . The supply port seal 23 comes into close contact with the supply nozzle 24 , similarly to the seals 15 a, 15 b, such that a supply path for air or the toner T extending from the supply tube 20 and supply mouthpiece 22 to the interior of the container is hermetically sealed from the outside. Thus, an air pump 30 becomes capable of supplying air. Note that the air pump 30 is a conventional, well-known diaphragm type air pump, and description thereof has been omitted. FIG. 4 shows the toner container 11 from below. It can be seen from FIG. 4 that the positions of the toner discharge mouthpiece portion 14 and discharge nozzle 14 a do not overlap the positions of the supply mouthpiece 22 * and supply nozzle 24 in the lengthwise direction. A toner discharging action of the toner replenishing device will now be described. When a toner replenishment signal is issued by the toner concentration sensor 34 of the developing device 4 , the air pump 30 is activated for a predetermined time period. Thus, air is supplied to the inside container 13 . At the start of use, the toner is carried on top of the inside container 13 and the front surface side of the inside container 13 is pressed by the gravitational force of the toner T. The inside container 13 then gradually expands from a position near the supply port such that the toner T is pushed forward (in the supply direction) slightly in accordance with the expansion of the inside container 13 . Next, the powder pump 40 is activated such that suction pressure is generated, and as a result, the toner T near the discharge port moves through the interior of the discharge tube 25 toward the left side of the drawing and is thus supplied to the developing device 4 via the powder pump 40 . This operation is repeated every time a replenishment signal is issued, whereby the inside container expands gradually, as shown in FIGS. 5 , 6 and 7 , and the toner T moves successively toward the discharge mouthpiece portion. The amount of replenishment toner supplied each time may be controlled by adjusting the activation time of the air pump 30 and the activation time of the powder pump. The powder pump 40 is a uniaxial eccentric screw pump formed from a rigid material such as metal or resin, and comprises a rotatable male screw-shaped rotor 41 , and a stator 42 formed from an elastic material such as rubber or soft resin and having a fixed, female screw-shaped hole. The rotor and stator are separated by a predetermined space that is hermetically sealed by a predetermined amount of interlocking. When the rotor rotates, the space moves and suction pressure is generated in the resulting replenishment path, allowing the toner T to move through the replenishment path. Second Embodiment FIG. 8 shows a developer replenishing device according to this embodiment. Parts common to both FIG. 8 and FIG. 1 have been allocated identical reference symbols, and duplicate description thereof has been omitted. In this embodiment, recovered toner recovered by the cleaning device 50 are conveyed by the suction and discharge of the air pump 30 such that a mixture of toner and air is supplied to the inside container 13 , and a space formed in the interior of the toner container 11 following toner discharge is used to store the recovered toner. Thus, a dedicated waste toner bottle is not required, enabling a reduce in component costs and a reduction in the size of the machine main body corresponding to the space required to provide the waste toner bottle. FIG. 9 shows the exterior of the toner container 11 . FIG. 10 shows one of the bag containers (the outside container or the inside container) of the toner container 11 before being formed into a bag shape. The bag container is constituted by four sheets, an upper surface sheet 61 , side face sheets 62 , 63 , and a bottom surface sheet 64 . The side face sheets are folded in half and sandwiched between the upper surface and bottom surface sheets, and then the sheets laminated as shown in the drawing. The sheets are then adhered to each other by adhering or welding approximately 2 to 10 mm of the periphery ( 65 a , 65 b , 65 c ). Heat welding enables particularly easy manufacture, and is therefore used most often. FIG. 11 shows the cross-section of the adhered sheets. In this embodiment, the inside container and outside container have a duplex structure, and therefore the inside container 13 is enveloped in the outside container 12 to form a structure such as that shown in FIG. 12 . The bottom surface of the outside container 12 and the bottom surface of the inside container 13 are welded or adhered to each other so that it is possible to expand only the outside container 12 or both the outside container and inside container. FIG. 13 shows a state in which only the outside container 12 is expanded. Third Embodiment FIG. 14 shows the exterior of a toner container according to this embodiment. In this embodiment, three heat-welded portions 80 a, 80 b, 80 c are provided such that the interior space is partitioned into four. The side of a reference symbol B in the drawing is the supply mouthpiece side, and when air or a mixture of air and toner is supplied from this side, first only the part extending from the B side to the welded part 80 a expands. When this part expands fully, the resultant expansion pressure causes the welded part 80 a to tear open such that the toner container expands into a connected space extending from the B side to the heat-welded portion 80 b. When more air or toner is supplied, the heat-welded portion 80 b also tears open such that the toner container expands into a connected space extending from B to the heat-welded portion 80 c, and when even more air or toner is supplied, finally the heat-welded portion 80 c tears open such that the toner container is fully expanded. Thus, the inside container 13 expands steadily and reliably from a position removed from the discharge port, and therefore all of the toner T in the outside container 12 is discharged reliably without becoming trapped between the inside container 13 and the upper surface of the outside container 12 . As a result, a superior toner replenishing device in which no toner remains after use can be realized. Various modifications will become possible for those skilled in the art after receiving the teachings of the present disclosure without departing from the scope thereof.
A toner replenishing device that provides a container and a device having a high toner volumetric efficiency and a low cost, suppresses vibration during replenishment to a minimum, and stores recovered toner without impairing the volumetric efficiency of unused toner is constituted by a developer replenishing device which is provided with a developer container storing a developer used in an image forming apparatus and replenishes a developing device of the image forming apparatus with the developer in the developer container. The developer container is rectangular in a horizontal direction, and comprises an outside container storing unused developer and a deformable inside container enveloped by the outside container. The developer replenishing device comprises a developer discharging mouthpiece portion for discharging the developer from the interior of the container, which is provided in a lengthwise direction end portion of the outside container, an air supply nozzle, provided in an opposite side end portion to the developer discharging mouthpiece portion in the lengthwise direction, for introducing air into the inside container, and an air pump for supplying air to the supply nozzle.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as an electrophotographic copier, a printer, a facsimile device, and a compound device thereof, and more particularly to a developer replenishing device suitable for use in this image forming apparatus.", "Description of the Related Art In an electrophotographic image forming apparatus, an image is typically created by forming a toner image using a so-called developer containing a toner and a carrier.", "The toner is steadily consumed as image formation progresses, and therefore a toner storage container serving as a toner cartridge filled with toner is generally used, and when all of the toner in the toner storage container has been consumed, new toner is supplied by replacing the toner storage container with a new toner storage container.", "Since toner is a powder, it is important to discharge the toner such that as little toner as possible remains in the toner storage container.", "Conventional methods for conveying toner from the interior of the container to a container outlet portion include a method of providing a screw known as an auger in the interior of the container and conveying the toner in a single direction by rotating the screw, a method of providing a spiral projection known as a screw bottle on the inner surface of a cylindrical portion of a tubular container and rotating the container such that the toner is conveyed little by little to an outlet portion of the container, and so on.", "The present inventor has proposed a method of discharging toner from a toner storage container by applying acceleration to the toner storage container through an asymmetric reciprocating motion such that the toner in the container is moved in a single direction by inertia and discharged through a discharge port provided in the downward direction of the container.", "In the toner conveyance method employing an auger, a member must be provided in the interior of the container and rotated, and therefore the structure of the container becomes complicated.", "In the toner conveyance method employing a screw bottle, no member need be provided in the interior of the container, and therefore the structure of the container is simple, but since the container is rotated, the container must be formed with a cylindrical main body and provided with an outlet in one end surface (the shape of a normal bottle laid on its side).", "Hence, in comparison with a rectangular parallelepiped-shaped container, the amount of toner that can be stored in the container is small, the container is not easy to hold and may slip out of the hand during replacement, and so on.", "Meanwhile, with the method of applying a reciprocating motion (in the lateral direction) to the container to move the toner inside the container such that the toner is discharged through a discharge port provided in the lower side of the container (to be referred to hereafter as a reciprocation method) a simple container shape such as a rectangular parallelepiped that can hold a large amount of toner (that has little dead space) may be employed, and since there is no need to provide a conveyor member inside the container, a low-cost, compact replenishing device can be realized.", "Moreover, a bag-shaped container constituted by a flexible sheet may be used, enabling savings in natural resources and costs.", "However, a reciprocation type replenishing device is greatly disadvantaged in that the resultant vibration causes abnormal images (banding).", "Hence, to cancel out the effect of vibration generated during reciprocation of the container on the main body, a method of providing a movable stopper and causing the container and stopper to collide at opposite phase speeds has been proposed.", "However, even slight vibration affects image formation, and therefore a replenishment method in which vibration is reduced to the greatest extent possible is required.", "Meanwhile, during image formation, residual toner is generated following transfer, and conventionally, this residual toner is recovered in a recovery bottle.", "A method of provided the container with a recovery chamber in advance and recovering the residual toner in the container has also been proposed, but when this method is employed, the constitution of a residual toner moving device and the capacity of the container decrease, and the cost of the container rises due to its complexity.", "It is therefore difficult to incorporate this method into an actual product.", "Technologies relating to the present invention are also disclosed in, e.g., Japanese Unexamined Patent Application Publication 2003-098813, Japanese Unexamined Patent Application Publication 2005-292300, Japanese Unexamined Patent Application Publication S63-010424, and Japanese Unexamined Patent Application Publication 2002-148924.", "SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner replenishing device for an image forming apparatus which can solve the conventional problems described above by realizing a container and a device having a high toner volumetric efficiency and a low cost, suppressing vibration during toner replenishment to a minimum, and storing recovered toner without impairing the volumetric efficiency of unused toner.", "In an aspect of the present invention, a developer replenishing device is provided with a developer container storing a developer used in an image forming apparatus, and replenishes a developing device of the image forming apparatus with the developer in the developer container.", "The developer container is rectangular in a horizontal direction, and comprises an outside container storing unused developer and a deformable inside container enveloped by the outside container.", "The developer replenishing device comprises a developer discharge port, provided in the outside container, for discharging the developer from the interior of the outside container;", "an air supply port for introducing air into the inside container;", "and air supplying means for supplying air to the air supply port.", "In another aspect of the present invention, a developer container stores a developer used in an image forming apparatus.", "The developer container is rectangular in a horizontal direction, and comprises an outside container storing unused developer and a deformable inside container enveloped by the outside container, and further comprises a developer discharge port, provided in the outside container, for discharging the developer from the interior of the outside container;", "and an air supply port for introducing air into the inside container.", "In another aspect of the present invention, an image forming apparatus uses a developer replenishing device.", "The developer replenishing device is provided with a developer container storing a developer used in the image forming apparatus, and replenishes a developing device of the image forming apparatus with the developer in the developer container.", "The developer container is rectangular in a horizontal direction, and comprises an outside container storing unused developer and a deformable inside container enveloped by the outside container.", "The developer replenishing device comprises a developer discharge port, provided in the outside container, for discharging the developer from the interior of the outside container;", "an air supply port for introducing air into the inside container;", "and air supplying means for supplying air to the air supply port.", "BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken with the accompanying drawings, in which: FIG. 1 is a view showing the overall constitution of an image forming apparatus (printer) to which the present invention is applied;", "FIG. 2 is a view showing the overall constitution of an electrophotographic image forming apparatus in which an embodiment of a developer replenishing device according to the present invention is used in a toner replenishment portion;", "FIG. 3 is a view showing a state in which a discharge outlet shutter is attached to a toner container shown in FIG. 2 ;", "FIG. 4 is an exterior perspective view of the toner container seen from below;", "FIGS. 5 to 7 are view showing a process of supplying toner from the toner container;", "FIG. 8 is a view showing the overall constitution of an image forming apparatus in which a second embodiment of the developer replenishing device according to the present invention is used in a toner replenishment portion;", "FIG. 9 is an exterior perspective view of a toner container shown in FIG. 8 ;", "FIG. 10 is a view showing one bag container (an outside container or an inside container) of the toner container before being formed into a bag shape;", "FIG. 11 is a sectional view of a sheet adhered to the bag container;", "FIG. 12 is a view showing that the bag container has a duplex structure consisting of the inside container and the outside container;", "FIG. 13 is a view showing a state in which only the outside container is expanded from the state shown in FIG. 12 ;", "and FIG. 14 is an exterior perspective view showing the constitution of a toner container according to a third embodiment of the present invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below on the basis of the attached drawings.", "First Embodiment FIG. 1 shows the overall constitution of an image forming apparatus (printer) to which this embodiment is applied.", "As shown in the drawing, in this image forming apparatus, four toner containers 131 Y, 131 M, 131 C, 131 K corresponding to four colors (yellow, magenta, cyan, black) are disposed detachably (replaceably) in a toner container storage portion above an image forming apparatus main body 100 .", "An intermediate transfer unit 130 is disposed beneath the toner container storage portion, and image creating portions 1 Y, 1 M, 1 C, 1 K corresponding to the four colors (yellow, magenta, cyan, black) are arranged in series so as to face an intermediate transfer belt 180 of the intermediate transfer unit 130 .", "For example, the image creating portion 1 Y corresponding to yellow is constituted by a photosensitive drum 2 Y, and a charging portion, a developing device (development portion), a cleaning portion, a neutralizing portion (not shown), and so on, which are arranged around the photosensitive drum 2 Y. Image creating processes (a charging process, an exposure process, a development process, a transfer process and a cleaning process) are implemented on the photosensitive drum 2 Y to form a yellow image on the photosensitive drum 2 Y. Apart from the color of the used toner, the other three image creating portions 1 M, 1 C, 1 K have a substantially identical constitution to the image creating portion 1 Y corresponding to yellow, and respectively form images in the corresponding toner colors.", "Accordingly, in the following description, the symbols Y, M, C, K denoting the colors will be omitted except where necessary.", "The photosensitive drum 2 is driven to rotate in the clockwise direction of the drawing by a drive motor, not shown in the drawing.", "Then, in the position of the charging portion, the surface of the photosensitive drum 2 is uniformly charged (charging process).", "An electrostatic latent image corresponding to yellow is then formed on the surface of the photosensitive drum 2 by exposing and scanning the surface of the photosensitive drum 2 with a laser beam emitted from an exposing device 120 in an irradiation position (exposure process).", "Next, the electrostatic latent image on the surface of the photosensitive drum 2 is developed in a position facing the developing device to form a yellow toner image (development process).", "The toner image on the photosensitive drum 2 is then transferred onto the intermediate transfer belt 180 in a position facing the intermediate transfer belt 180 and a primary transfer bias rollers 140 Y, 140 M, 140 C, 140 K (primary transfer process).", "At this time, a small amount of non-transferred toner remains on the photosensitive drum 2 .", "However, the non-transferred toner remaining on the photosensitive drum 2 is then mechanically recovered by a cleaning blade in a position facing the cleaning portion (cleaning process).", "Finally, the remaining potential on the photosensitive drum 2 is removed in a position facing the neutralizing portion, not shown in the drawing, whereupon the series of image creating processes executed on the photosensitive drum 2 is terminated.", "The other image creating portions 1 M, 1 C, 1 K perform the image creating processes described above in a similar manner to the yellow image creating portion 1 Y, whereupon the toner image of each color formed on the respective photosensitive drums 2 are superposed onto the intermediate transfer belt 180 such that a color image is formed on the intermediate transfer belt 180 .", "The intermediate transfer unit 130 is constituted by the intermediate transfer belt 180 , four primary transfer bias rollers, a secondary transfer backup roller 180 a, a cleaning backup roller, a tension roller 180 c, an intermediate transfer cleaning portion 190 , and so on.", "The intermediate transfer belt 180 is stretched and supported by the two rollers 180 a, 180 c, and is moved in the direction of the arrow in FIG. 1 when one of the rollers is driven to rotate.", "The four primary transfer bias rollers 140 Y, 140 M, 140 C, 140 K sandwich the intermediate transfer belt 180 on the opposite side of the photosensitive drum 2 to form a primary transfer nip.", "A transfer bias having a reverse polarity to the polarity of the toner is applied to the primary transfer bias roller 140 .", "The intermediate transfer belt 180 travels in the direction of the arrow in the drawing, thereby passing through the primary transfer nip of each primary transfer bias roller 140 in sequence, and thus the toner images of the four colors on the respective photosensitive drums 2 are subjected to primary transfer so as to be superposed onto the intermediate transfer belt 180 .", "Next, in the position of a secondary transfer nip formed by sandwiching the intermediate transfer belt 180 between the secondary transfer backup roller 180 a and a secondary transfer roller 141 , the color toner image formed on the intermediate transfer belt 180 is transferred onto a copying subject material P such as transfer paper that has been conveyed to the position of the secondary transfer nip.", "At this time, non-transferred toner that has not been transferred onto the copying subject material P remains on the intermediate transfer belt 180 , and therefore the non-transferred toner on the intermediate transfer belt 180 is recovered in the position of the intermediate transfer cleaning portion 190 , whereupon the series of transfer processes executed on the intermediate transfer belt 180 is terminated.", "Note that the copying subject material P conveyed to the position of the secondary transfer nip is conveyed from a tray 160 disposed beneath the apparatus main body via a feed roller 160 a, a registration roller pair 151 , and so on.", "A plurality of sheets of the copying subject material P such as transfer paper are stacked and stored on the tray 160 , and by driving the feed roller 160 a to rotate in the counter-clockwise direction of FIG. 1 , the uppermost sheet of the copying subject material P is fed between the rollers of the registration roller pair 151 .", "The copying subject material P conveyed to the registration roller pair 151 is halted temporarily in the position of a roller nip formed when rotation of the registration roller pair 151 is halted, and at a timing corresponding to the color image on the intermediate transfer belt 180 , the registration roller pair 151 are driven to rotate such that the copying subject material P is conveyed toward the secondary transfer nip.", "Once the color image has been transferred onto the copying subject material P in the position of the secondary transfer nip, the copying subject material P is conveyed to a fixing portion 170 , where heat and pressure are supplied from a fixing roller, a pressure roller, and so on to fix the color image transferred onto the surface.", "The copying subject material P is then discharged to the exterior of the apparatus via a discharge roller pair, and stacked.", "At this point, the series of image forming processes executed by the image forming apparatus is terminated.", "FIG. 2 shows an example of an electrophotographic image forming apparatus using a developer replenishing device according to this embodiment in a toner replenishing portion.", "In the drawing, the reference numeral 2 denotes a photosensitive body.", "Similarly to a typical electrophotographic process, a uniform charge is applied to the photosensitive body 2 by a charging device 3 , and then the photosensitive body 2 receives exposure light L corresponding to an image formed by an exposing device, not shown in the drawing, whereby an electrostatic latent image is formed thereon.", "The reference numeral 4 in the drawing denotes a developing device, which is a unit for forming a toner image by developing the electrostatic latent image using toner.", "The reference numeral 50 in the drawing is a conventional, well-known cleaning device for recovering residual toner from the photosensitive body 2 following transfer and transferring the toner to a recovery bottle, not shown in the drawing.", "In this apparatus, the toner image formed on the photosensitive body 2 is transferred onto a sheet of transfer paper fed from a feeding device, not shown in the drawing, by a transfer device, not shown in the drawing (or via an intermediate transfer belt).", "The toner image is then fixed onto the transfer paper by a fixing device, not shown in the drawing, whereupon the image is output.", "The reference numeral 5 in the drawing denotes a toner container having a substantially square or substantially rectangular front surface cross-section and formed so as to extend horizontally in the lengthwise direction.", "The toner container 5 is attached from the right side to the left side in the drawing.", "Assuming that the right side of the drawing is the front surface of the apparatus main body, for example, the toner container 5 is inserted toward the rear side from the main body front surface.", "A toner replenishing device 10 for replenishing toner consumed during image formation is provided in series with the developing device 4 .", "The developing device 4 shown in the drawing is a so-called two-component developing device that stores a developer 8 formed by mixing together a toner and a carrier.", "The reference symbols 5 a and 6 a in the drawing denote two conveyance screws for agitating the developer.", "Further, the reference numeral 7 in the drawing denotes a development roller having magnets of different polarities fixed to the interior thereof and a sleeve that rotates on the outer periphery thereof.", "The development roller 7 creates a toner image by developing a latent image while holding the agitated developer on the sleeve of the roller surface with the magnets.", "The reference numeral 9 in the drawing denotes a doctor blade, which is used to restrict the developer on the development roller to a fixed height.", "In the developing device 4 , toner is consumed steadily as image formation progresses.", "The developing device 4 comprises a toner concentration sensor 34 that constantly detects the toner concentration of the developer 8 .", "When the toner concentration of the developer 8 falls below a predetermined value, control is performed to transmit an operation signal to the toner replenishing device 10 .", "The toner replenishing device 10 serves as a part for replenishing toner.", "An outside container 12 and an inside container 13 constituting the toner container 11 are flexible, bag-shaped toner storage members formed by one or more layers of a flexible sheet made of resin, such as polyethylene or nylon, or paper and having a thickness of approximately 50 to 200 μm.", "The reference numeral 14 in the drawing denotes a discharge mouthpiece portion provided with a toner discharge port 14 a, which is constituted by a hard material such as resin and welded or adhered to the outside container 12 as shown in the drawing.", "When the same material is used for the flexible members and the rigid member, the materials do not have to be separated when the container is reused, and therefore an improvement in recycling efficiency is achieved.", "New toner T is stored in the outside container 12 , and when the toner T is consumed, the whole container is exchanged for a new one.", "The reference numeral 15 in the drawing denotes a rigid base plate made of resin or the like, which is fixed detachably to the flexible container through fitting, adhesion, or the like so that the container can be attached easily to the machine main body.", "The used toner container 11 may be sent back to the maker from the user for recycling and reuse.", "In this case, the flexible container alone may be incinerated and used as thermal energy, and the hard members such as the base plate and mouthpiece may be reused.", "Incinerating members that use few natural resources and reusing components that use a lot of natural resources in this manner is an extremely effective method of recycling.", "The reference numeral 22 in the drawing denotes a supply mouthpiece comprising a supply port for supplying air to the inside container 13 .", "The supply mouthpiece 22 is constituted by a hard material such as resin, and is adhered to the inside container 13 and outside container 12 as shown in the drawing.", "Similarly to the discharge mouthpiece, when the supply mouthpiece 22 uses an identical material to the flexible members, an improvement in recycling efficiency is achieved.", "As described above, when the toner container 11 is attached in the direction of an arrow A in the drawing by a guide member, not shown in the drawing, provided on the replenishing device main body, a discharge nozzle 16 is attached to the discharge mouthpiece 14 while pushing a discharge port shutter 17 toward the right side of the drawing.", "The discharge mouthpiece is provided with seals 15 a , 15 b which come into close contact with the discharge nozzle 16 and the shutter 17 , respectively, such that a toner discharge path extending from the interior of the container to the discharge port 14 a , a discharge tube 25 , and a powder pump 40 is hermetically sealed from the outside.", "Thus, the powder pump 40 becomes capable of pumping the toner T through suction pressure, as will be described below.", "A member 18 is biased upwardly by a spring 19 .", "FIG. 3 shows a state in which the discharge port shutter 17 is attached to the toner container 11 of FIG. 1 (a state prior to insertion of the shutter or when the container has been detached from the main body).", "When attaching the toner container 11 , a supply nozzle 24 is simultaneously inserted into a slit provided in a supply port seal 23 formed from a sponge material and attached to the supply mouthpiece 22 .", "The supply port seal 23 comes into close contact with the supply nozzle 24 , similarly to the seals 15 a, 15 b, such that a supply path for air or the toner T extending from the supply tube 20 and supply mouthpiece 22 to the interior of the container is hermetically sealed from the outside.", "Thus, an air pump 30 becomes capable of supplying air.", "Note that the air pump 30 is a conventional, well-known diaphragm type air pump, and description thereof has been omitted.", "FIG. 4 shows the toner container 11 from below.", "It can be seen from FIG. 4 that the positions of the toner discharge mouthpiece portion 14 and discharge nozzle 14 a do not overlap the positions of the supply mouthpiece 22 * and supply nozzle 24 in the lengthwise direction.", "A toner discharging action of the toner replenishing device will now be described.", "When a toner replenishment signal is issued by the toner concentration sensor 34 of the developing device 4 , the air pump 30 is activated for a predetermined time period.", "Thus, air is supplied to the inside container 13 .", "At the start of use, the toner is carried on top of the inside container 13 and the front surface side of the inside container 13 is pressed by the gravitational force of the toner T. The inside container 13 then gradually expands from a position near the supply port such that the toner T is pushed forward (in the supply direction) slightly in accordance with the expansion of the inside container 13 .", "Next, the powder pump 40 is activated such that suction pressure is generated, and as a result, the toner T near the discharge port moves through the interior of the discharge tube 25 toward the left side of the drawing and is thus supplied to the developing device 4 via the powder pump 40 .", "This operation is repeated every time a replenishment signal is issued, whereby the inside container expands gradually, as shown in FIGS. 5 , 6 and 7 , and the toner T moves successively toward the discharge mouthpiece portion.", "The amount of replenishment toner supplied each time may be controlled by adjusting the activation time of the air pump 30 and the activation time of the powder pump.", "The powder pump 40 is a uniaxial eccentric screw pump formed from a rigid material such as metal or resin, and comprises a rotatable male screw-shaped rotor 41 , and a stator 42 formed from an elastic material such as rubber or soft resin and having a fixed, female screw-shaped hole.", "The rotor and stator are separated by a predetermined space that is hermetically sealed by a predetermined amount of interlocking.", "When the rotor rotates, the space moves and suction pressure is generated in the resulting replenishment path, allowing the toner T to move through the replenishment path.", "Second Embodiment FIG. 8 shows a developer replenishing device according to this embodiment.", "Parts common to both FIG. 8 and FIG. 1 have been allocated identical reference symbols, and duplicate description thereof has been omitted.", "In this embodiment, recovered toner recovered by the cleaning device 50 are conveyed by the suction and discharge of the air pump 30 such that a mixture of toner and air is supplied to the inside container 13 , and a space formed in the interior of the toner container 11 following toner discharge is used to store the recovered toner.", "Thus, a dedicated waste toner bottle is not required, enabling a reduce in component costs and a reduction in the size of the machine main body corresponding to the space required to provide the waste toner bottle.", "FIG. 9 shows the exterior of the toner container 11 .", "FIG. 10 shows one of the bag containers (the outside container or the inside container) of the toner container 11 before being formed into a bag shape.", "The bag container is constituted by four sheets, an upper surface sheet 61 , side face sheets 62 , 63 , and a bottom surface sheet 64 .", "The side face sheets are folded in half and sandwiched between the upper surface and bottom surface sheets, and then the sheets laminated as shown in the drawing.", "The sheets are then adhered to each other by adhering or welding approximately 2 to 10 mm of the periphery ( 65 a , 65 b , 65 c ).", "Heat welding enables particularly easy manufacture, and is therefore used most often.", "FIG. 11 shows the cross-section of the adhered sheets.", "In this embodiment, the inside container and outside container have a duplex structure, and therefore the inside container 13 is enveloped in the outside container 12 to form a structure such as that shown in FIG. 12 .", "The bottom surface of the outside container 12 and the bottom surface of the inside container 13 are welded or adhered to each other so that it is possible to expand only the outside container 12 or both the outside container and inside container.", "FIG. 13 shows a state in which only the outside container 12 is expanded.", "Third Embodiment FIG. 14 shows the exterior of a toner container according to this embodiment.", "In this embodiment, three heat-welded portions 80 a, 80 b, 80 c are provided such that the interior space is partitioned into four.", "The side of a reference symbol B in the drawing is the supply mouthpiece side, and when air or a mixture of air and toner is supplied from this side, first only the part extending from the B side to the welded part 80 a expands.", "When this part expands fully, the resultant expansion pressure causes the welded part 80 a to tear open such that the toner container expands into a connected space extending from the B side to the heat-welded portion 80 b. When more air or toner is supplied, the heat-welded portion 80 b also tears open such that the toner container expands into a connected space extending from B to the heat-welded portion 80 c, and when even more air or toner is supplied, finally the heat-welded portion 80 c tears open such that the toner container is fully expanded.", "Thus, the inside container 13 expands steadily and reliably from a position removed from the discharge port, and therefore all of the toner T in the outside container 12 is discharged reliably without becoming trapped between the inside container 13 and the upper surface of the outside container 12 .", "As a result, a superior toner replenishing device in which no toner remains after use can be realized.", "Various modifications will become possible for those skilled in the art after receiving the teachings of the present disclosure without departing from the scope thereof." ]
This is a continuation of U.S. application Ser. No. 08/026,239, filed Mar. 1, 1993, now abandoned, which is a continuation of U.S. application Ser. No. 07/780,6654 filed Oct. 18, 1990, now abandoned. FIELD OF THE INVENTION The present invention relates to position control system, particularly those position systems being advantageously used with optical disk recorders. BACKGROUND OF THE INVENTION Both magnetic and optical disk recorders employ either a 14 large plurality of concentric record tracks or a single spiraling record track. The tracks on optical disks are identified by any one of a plurality of surface configurations on the optical medium (disk). A common configuration is a disk-shaped medium having circularly concentric Groove or a single spiral groove, for indicating the location of the record tracks. In both magnetic and optical disks recorders, means are provided for faithfully following one of the addressed record tracks. When it is desired to scan a track other than a currently scanned track, a track seek operation is provided; that is, the track following is aborted and a track seek algorithm is initiated which causes the effective disconnection of the track following operation. When seeking from one track to another track, magnetic and optical recorder must keep track of its current track on the disk as well as the desired track. This is typically done using a tracking error signal (TES). Tracks are counted as a recording head is moved radially across the tracks between the current track and the desired track. As is well known in the art, during a seek operation, a light beam is moved along with the recording head radially across the tracks. As the light beam moves across the tracks, the TES appears as a sinusoidal or substantial sinusoidal waveform. The peaks of TES are produced at the cliffs between the tracks and grooves on the disk surface. In this manner, the tracks are one full cycle apart. The simplest method of determining position from the TES is to produce a pulse whenever the TES crosses a zero reference point and then count these pulses. This method, however, is susceptible to miscounting due to noise and disk defects. A superior method, which is used today, utilizes a plurality of TES detectors to indicate zero crossing points and positive and negative peaks. Two peaks of opposite polarities must be encountered before a track crossing is counted. This method allows for greater noise tolerance on the TES. However, media defects can still occasionally result in either the seek operation being too long, i.e. it missed counting a track, or the seek being too short, i.e. counting a defect as a track. As is known in the art, both of these conditions can be recovered from quickly and easily. The only time a defect can cause a serious problem is when it occurs at the end of the seek operation when a tracking servo is activated. The tracking servo attempts to maintain the TES at the zero reference point. If the tracking servo is activated on a upward slope of the TES when the seeking operation is in a direction toward an outer edge of the disk, the tracking servo will lock on the target track. If, however, the tracking servo is activated on the downward slope, the TES would be opposite to what is needed for a stable condition. Thus, the recording head will "skate" over the disk. In essence, the head will move at an accelerated pace during the downward slope and decelerate over the upward slope. As a result of this activity, a time consuming recovery procedure must activated to stop the skating motion and to lock on the target track. Thus, it is important to activate the tracking servo on the correct slope after a seek operation. U.S. Pat. No. 4,839,876 discloses an optical disk recorder which includes a position servo control loop for causing a beam of radiation to faithfully follow a track on the disk, jump from a current track to an adjacent track or to a small number of tracks away from the current track. Operation of the position servo loop is altered by selectively reversing the phase of a differentiated position error signal and integrating the differentiated position error signal for comparison with a sawtooth signal for moving the beam of radiation from the current track to an immediately adjacent track under continuous position servo control. Upon reaching the adjacent track, the sawtooth signal returns to a reference potential for initiating track following. The servo error signal and the sawtooth signal does not cause any significant perturbations in the positioning servo loop operation. This patent does not address the problem encountering media defects during a seek operation. U.S. Pat. No. 5,038,333 discloses a track-seeking apparatus of a disk recorder which employs a track-crossing sensor to produce track-crossing signals. An oscillator is slaved to the sensor for supplying substitute track-crossing pulses in the absence of the sensor providing such pulses or when the radial velocity exceeds a threshold velocity. A velocity profile means alters the oscillator frequency so that the oscillator produces track-crossing pulses in accordance with the profile. This patent does not address the problem of the encountering media defects during a seek operation. U.S. Pat. No. 5,001,732 discloses a track counter for optical disk which counts the number of tracks a light beam passes upon when an optical head moves over an optical disk in a radial direction. The track counter includes a passage signal generating circuit which generates a signal each time the reflected light of the the light beam passes over a track. A counter counts the signals generated by the passage signal generating circuit. A counter suspending circuit determines that the light beam will pass over a specific position of a track and suspends the action of the counter for a predetermined period of time. A count value compensating circuit assumes the number of tracks the light beam passed during the predetermined period of time and adds this assumed number to the count value of the counter. This invention address problems on the disk in designated areas. It does not address the problem of encountering media defects which may occur in areas other than the designated areas. Accordingly, it is desired to provide for a drive which is less susceptible to poor optical media quality and provides for more reliability during seek operations. SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved positioning system having enhanced track counting and accommodation of defects during track seeking operations. In an optical disk recorder, during the sensing of closely-spaced, position-indicating, machine-sensible indicia, a first peak of a track error signal is detected. In response to the first peak being detected, a half-track counter is decremented from a value which depends upon the position of the destination track relative to a current track. In response to the occurrence of a selected value of the half-track counter and the presence of a zero crossing of the tracking error signal, a first timer is activated to mask any defects occurring during the selected first half cycle of the last cycle of the tracking error signal. The half-track counter is again decremented in response to a second peak being detected and the occurrence of a next-to-last zero crossing of the tracking error signal and a second timer is then activated to mask any subsequent defects occurring during the second half cycle of the tracking error signal. The seek operation is terminated when the count value in the half-track counter equals zero and a final zero crossing is detected. Thereafter, a track following operation is activated. The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a simplified block diagram of an optical disk recorder/player in accordance with the present invention. FIG. 2 spatially illustrates the relationship of tracks and tracking error signals. FIG. 3 is a waveform illustrating a defect occurring during a second half cycle of the last cycle of a tracking error signal. FIG. 4 is a block diagram of a circuit for masking the type of defect shown in FIG. 3 in accordance with the present invention. FIG. 5 is a waveform illustrating a defect occurring during the first and second half cycles of the last cycle of a tracking error signal. FIG. 6 is a block diagram of a circuit for masking the types of defects shown in FIG. 5 in accordance with the present invention. FIG. 7 is a flow chart illustrating the steps utilized in masking the defects shown in FIGS. 3 and 5. DETAILED DESCRIPTION Referring now more particularly to the appended drawing, like numerals indicate like structural parts and features in the various figures. An optical recorder with which the present invention may be advantageously employed is shown in FIG. 1. A magnetooptic record disk 30 is mounted on spindle 31 for rotation by motor 32. Optical head-carrying arm 33 on head-arm carriage generally denoted by numeral 34, moves radially of disk 30. A frame 35 of recorder suitably mounts carriage 34 for reciprocating radial motions. The radial motions of carriage 34 enable access to any one of a plurality of concentric tracks or circumvolutions of a spiral track for recording and recovering data on and from the disk. Linear actuator 36 suitably mounted on frame 35, radially moves carriage 34 for enabling track accessing. The recorder is suitably attached to one or more host processors 37, such host processors may be control units, personal computers, large system computers, communication systems, image process processors, and the like. Attaching circuits 38 provide the logical and electrical connections between the optical recorder and the attaching host processors 37. Microprocessor 40 controls the recorder including the attachment to the host processor 37. Control data, status data, commands and the like are exchanged between attaching circuits 38 and microprocessor 40 via bidirectional bus 43. Included in microprocessor 40 is a program or microcode storing, read-only memory (ROM) 41 and a data and control signal storing random access memory (RAM) 42. The optics of the recorder include an objective or focussing lens 45 mounted for focussing and tracking motions on head-arm 33 by fine actuator 46. This actuator includes mechanisms for moving lens 45 toward and away from disk 30 for focussing and for radial movements parallel to carriage 34 motions; for example, for changing tracks within a range of 100 tracks so that carriage 34 need not be actuated each time a track adjacent to a track currently being accessed is to be accessed. Numeral 47 denotes a two-way light path between lens 45 and disk 30. In magnetooptic recording, magnet 48 (in a constructed embodiment magnet 48 is an electromagnet) provides a weak magnetic steering field for directing the remnant magnetization direction of a small spot on disk 30 illuminated by laser light from lens 45. The laser light spot heats the illuminated spot on the record disk to a temperature above the Curie point of the magnetooptic layer (not shown, but can be an alloy of rare earth and transitional metals as taught by Chaudhari et al., U.S. Pat. No. 3,949,387). This heating enables magnet 48 to direct the remnant magnetization to a desired direction of magnetization as the spot cools below the Curie point temperature. Magnet 48 is shown as oriented in the "write" direction, i.e., binary ones recorded on disk 30 normally are "north pole remnant magnetization". To erase disk 30, magnet 48 rotates so the south pole is adjacent disk 30. Magnet 48 control 49, which is mechanically coupled to rotatable magnet 48 as indicated by dashed line 50, controls the write and erase directions. Microprocessor 40 supplies control signals over line 51 to control 49 for effecting reversal of the recording direction. It is necessary to control the radial position of the beam following path 47, such that a track or circumvolution is faithfully followed and that a desired track or circumvolution is quickly and precisely accessed. To this end, focus and tracking circuits 54 control both the coarse actuator 36 and fine actuator 46. The positioning of carriage 34 by actuator 36 is precisely controlled by control signals supplied by circuits 54 over line 55 to actuator 36. Additionally, circuits 54 control signals travel over lines 57 and 58, respectively, for focus and fine tracking and switching actions of fine actuator 46. Lines 57, 58 respectively carry a position error signal to circuits 54 and a position control signal from circuits 54 to the focus and tracking mechanisms of actuator 46. Sensor 56 senses the relative position of fine actuator 46 to head-arm carriage 33. The focus and tracking position sensing is achieved by analyzing laser light reflected from disk 30 over path 47, thence through lens 45, through one-half mirror 60 and to be reflected by half-mirror 61 to a so-called "quad detector" 62. Quad detector 62 has four photo elements which respectively supply signals on four lines collectively denominated by numeral 63 to focus and tracking circuits 54. Aligning one axis of the detector 62 with a track center line, track following operations are enabled. Focussing operations are achieved by comparing the light intensities detected by the four photo elements in the quad detector 62. Focus and tracking circuits 54 analyze the signals on lines 63 to control both focus and tracking. Recording or writing data onto disk 30 is next described. It is assumed that magnet 48 is rotated to the desired position for recording data. Microprocessor 40 supplies a control signal over line 65 to laser control 66 for indicating that a recording operation is to ensue. This means that laser 67 is energized by control 66 to emit a high-intensity, laser light beam for recording; in contrast, for reading, the laser 67 emitted laser light beam is a reduced intensity for not heating the laser illuminated spot on disk 30 above the Curie point. Control 66 supplies its control signal over line 68 to laser 67 and receives a feedback signal over line 69 indicating the laser 67 emitted light intensity. Control 68 adjusts the light intensity to the desired value. Laser 67, a semiconductor laser such as a gallium arsenide diode laser, can be modulated by data signals so the emitted light beam represents the data to be recorded by intensity modulation. In this regard, data circuits 75 (later described) supply data-indicating signals over line 78 to laser 67 for effecting such modulation. This modulated light beam passes through polarizer 70 (linearly polarizing the beam), thence through collimating lens 71 toward half mirror 60 for being reflected toward disk 30 through lens 45. Data circuits 75 are prepared for recording by the microprocessor 40 supplied control signals over line 76. Microprocessor 40 in preparing circuits 75 is responding to commands for recording received from a host processor 37 via attaching circuits 38. Once data circuits 75 are prepared, data is transferred directly between host processor 37 to data circuits 75 through attaching circuits 38. Data circuits 75 also includes ancillary circuits (not shown) relating to disk 30 format signals, error detection and correction and the like. Circuits 75, during a read or recovery action, strip the ancillary signals from the readback signals before supply corrected data signals over bus 77 to host processor 37 via attaching to 38. Reading or recovering data from disk 30 for transmission to a host processor requires optical and electrical processing of the laser light beam from the disk 30. That portion of the reflected light (which has its linear polarization from polarizer 70 rotated by disk 30 recording using the Kerr effect) travels along the two-way light path 47, through lens 45 and half-mirrors 60 and 61 to the data detection portion 79 of the head-arm 33 optics. Half-mirror or beam splitter 80 divides the reflected beam into two equal intensity beams both having the same reflected rotated linear polarization. The half-mirror 80 reflected light travels through a first polarizer 81, which is set to pass only that reflected light which was rotated when the remnant magnetization on disk 30 spot being accessed has a "north" or binary one indication. This passed light impinges on photo cell 82 for supplying a suitable indicating signal to differential amplifier 85. When the reflected light was rotated by a "south" or erased pole direction remnant magnetization, then polarizer 81 passes no or very little light resulting in no active signal being supplied by photocell 82. The opposite operation occurs by polarizer 83 which passes only "south" rotated laser light beam to photo cell 84. Photocell 84 supplies its signal indicating its received laser light to the second input of differential amplifier 85. The amplifier 85 supplies the resulting difference signal (data representing) to data circuits 75 for detection. The detected signals include not only data that is recorded but also all of the so-called ancillary signals as well. The term "data" as used herein is intended to include any and all information-bearing signals, preferably of the digital or discrete value type. The rotational position and rotational speed of spindle 31 is sensed by a suitable tachometer or emitter sensor 90. Sensor 90, preferably of the optical sensing type that senses dark and light spots on a tachometer wheel (not shown) of spindle 31, supplies the "tach" signals (digital signals) to RPS circuit 91 which detects the rotational position of spindle 31 and supplies rotational information-bearing signals to microprocessor 40. Microprocessor 40 employs such rotational signals for controlling access to data storing segments on disk 30 as is widely practiced in the magnetic data storing disks. Additionally, the sensor 90 signals also travel to spindle speed control circuits 93 for controlling motor 32 to rotate spindle 31 at a constant rotational speed. Control 93 may include a crystal controlled oscillator for controlling motor 32 speed, as is well known. Microprocessor 40 supplies control signals over line 94 to control 93 in the usual manner. Referring to FIG. 2, a portion of the information-bearing surface of disk 30 is illustrated. The disk 30 is formed with two sets of concentric rings, one set being tracks or mesas 100 and the second set being grooves 102. When the light beam 47 is focused into a groove 102, the TES is at a zero crossing position 104, i.e. when exactly centered, the sensed TES should be at zero. As the light beam 47 moves from one track to another track, the amplitude of TES changes as a sinusoid with the direction of change indicating the direction of tracking error. As the light beam 47 scans transversely (radially) across the tracks 100 or grooves 102, TES takes the sinusoidal shape wherein zero axis crossings in a first direction signify crossing the center of the grooves. Similarly, when the light beam 47 is crossing the tracks 100, the zero access crossing of TES is in the opposite direction. In essence, the peaks of TES are produced at the cliffs between the tracks 100 and the grooves 102 on the surface of the disk 30. FIG. 3 illustrates a portion of a TES signal 110 wherein a defect 112 occurs during the last half cycle of the signal. It is understood that a seek in an opposite direction would invert the polarity of the TES and its slope in the discussion to follow. As stated above, one method of minimizing the susceptibility of the optical recorder to noise and disk defects is to use three TES detectors (not shown). These detectors indicate when the TES crosses a zero reference point and the positive peaks and the negative peaks of TES. Two peaks of opposite polarities must be encountered before a track is counted. Further as noted above, the TES signal 110 is sinusoidal whose positive peak exceeds a positive threshold 116 and whose negative peak exceeds a negative threshold 118. The positive and negative peaks of TES signal 110 must exceed the respective thresholds 116 and 118 in order to be considered a peak during a seek operation. Moreover, the TES signal 110 normally crosses a zero reference point 114 between positive and negative peaks. At the conclusion of a seek operation, a track servo (not shown) is activated to continue a track following operation on the desired track. Detail of the tracking circuits are disclosed in U.S. Pat. No. 5,038,333 which issued to W. W. Chow et al, assigned to the assignee of the present case and is hereby incorporated herein by reference. During the second half cycle of the last cycle of the TES signal 110, the defect 112 causes the detection of a negative pulse which exceeds the negative threshold 118 and could be interpreted as a zero crossing. The tracking servo normally activates after sequence of a positive pulse, a first zero crossing, a negative pulse and a second zero crossing. Moreover, if the tracking servo activates on an upward slope of the TES signal 110 after encountering the above sequence, it will be in a stable condition and will successfully lock onto the desired track. In view of the defect 112, the sequence includes a positive pulse, a first zero crossing, a negative pulse and a second zero crossing. However, the slope of the TES signal 110 is downward which cause an unstable condition when the tracking servo activates and causes a error in a subsequent track following operation. FIG. 4 shows a block diagram of a masking circuit 130 which eliminates the error caused by the defect 112 (FIG. 3) encountered during the last half cycle of the TES signal 110. Circuit 130 includes a half-track counter 132. Prior to a seek operation, counter 132 is loaded with a count value which is equal to the number of half-tracks between the present track and the desired track. For purposes of illustration and not limitation, if a seek operation to be executed involves a movement to a track which is two tracks away from the current track, the count value in counter 132 is set equal to a value of four which coincides to four half-tracks. Thereafter, counter 132 is decremented one count for each half-track of movement. As is shown in FIG. 3, one half-track is equal to one half cycle of the TES signal 110. Circuit 130 further includes an AND gate 134 which receives an indication when the TES signal 110 performs a zero crossing and and input from a decoder/comparator 136. Comparator 136 compares the count value of the counter 132 with a value of one. Gate 134 is coupled to a timer circuit 138. The timer circuit 138 is coupled to the seek control logic 140. The details of the timer circuit and the seek control logic are well known in the art and will not be discussed here. In operation, during a seek operation, the optical recorder will always arrive at the destination or desired track with a constant velocity plus or minus some tolerance. Thus, any defect that may occur during the downward slope of the last peak can be masked out. The timer circuit 138 is activated upon the occurrence of the next-to-last zero crossing of the TES signal 110 and a count value of one in the counter 132. The next-to-last zero crossing of the TES signal 110 occurs when the count value of the counter 132 equals a value of one and zero crossing of the TES signal occurs. The activation of timer circuit 138 facilitates the blocking of the final zero crossing point of the TES signal 110 for a predetermined time. The timer circuit 138 must have a time interval which is equal to the time required to reach a last peak immediately prior to the required time to terminate the seek operation. FIG. 5 illustrates a TES signal 110' wherein a defect 150 occurs in the first half cycle and a defect 152 occurs during the second half cycle of the signal. The TES signal 110' is sinusoidal whose positive peak exceed a positive threshold 116' and whose negative peak exceed a negative threshold 118'. The positive and negative peaks of TES signal 110' must exceed the respective thresholds 116' and 118' in order to be considered a peak during a seek operation. Moreover, the TES signal 110' normally crosses a zero reference point 114' between positive and negative peaks. Although defect 150 is slightly different from defect 112, the same techniques can be used to resolve the media defect condition. As illustrated in FIG. 5, defect 150 goes beyond the threshold point 118' and would appear as a true track crossing. With this condition, the normal seek algorithm would be fooled into activating the tracking servo on the wrong slope of the TES signal 110'. Moreover, as set forth above, in view of the constant and predictable velocity (within a specific tolerance) at the end of the seek operation, it can be predicted, using a masking circuit similar to circuit 130, that the last peak caused by defect 150 comes well before the predicted time. FIG. 6 illustrates a block diagram of a masking circuit 160 which eliminates the errors caused by the defects 150 and 152 (FIG. 5). Circuit 160 includes a half-track counter 132'. Prior to a seek operation, counter 132' is loaded with a count value which is equal to the number of half-tracks between the present track and the desired track. For purposes of illustration and not limitation, if a seek operation to be executed involves a movement to a track which is two tracks away from the current track, the count value in counter 132' is set equal to a value of four which coincides to four half-tracks. Thereafter, counter 132' is decremented one count for each half-track of movement. Circuit 160 further includes an AND gate 134' which receives an indication when the TES signal 110' performs a zero crossing and an input from a decoder/comparator 136'. Comparator 136' compares the count value of the counter 132' with values of one and two. AND gate 134' is coupled to a first timer circuit 138'. The first timer circuit 138' is coupled an input of an AND gate 139. AND gates 134' and 139 each receive an input from the comparator 136' and an indication when a zero crossing has occurred. AND gate 139 is coupled to a second timer circuit 144. The second timer circuit 144 is coupled to the seek control logic 148. The details of the timer circuits 138' and 144, and the seek control logic 148 are well known in the art and will not be discussed here. In operation, during a seek operation, the optical recorder will always arrive at the destination or desired track with a constant velocity plus or minus some tolerance. Thus, any defect that may occur during the downward slope of the last peak can be masked out. The first timer circuit 138' is activated upon the occurrence of the zero crossing of the TES signal 110' and when the count value of the half-track counter 132' equals two. The count value of two in the half-track counter 132' represents either the first half cycle of the TES signal 110' if the destination track is the next adjacent track or the first half cycle of the last track prior to the destination track. The activation of the first timer circuit 138' facilitates the blocking of the defect 150 of the TES signal 110' for a predetermined time. The first timer circuit 138' must have a time interval which is equal to the time required to reach beyond the expected passing of threshold 116' but prior to the next-to-last zero crossing point 145 (FIG.5). When the first timer 138' has timed-out, it sends a signal to AND gate 139. Upon the occurrence of a count value of one in the half-track counter 136' and that of the next-to-last zero crossing point, the second timer circuit 144 is activated to mask out the defect 152 in a similar manner set forth above for defect 112. FIG. 7 is a flow chart which illustrates the steps utilized in masking out media defects encountered during a seek operation in accordance with the present invention. In step 170, prior to initiating the seek operation, the half-track counter 132 or 132' are loaded with the appropriate count value reflective of the number of half-tracks between the current track and the destination or desired track. Step 172 determines whether a first peak has been detected. Step 174 decrements the half-track counter 132 or 132' subsequent to the detection of the first peak. Step 176 determines whether a second peak has been detected and whether the first mask procedure has not been activated. Step 178 facilitates the decrementing of the half-track counter 132 or 132' in response to the second peak being detected and the first mask procedure not being activated. Step 180 determines whether the half-track counter 132 or 132' has reached a count of zero. Step 182 determines whether the second mask procedure is activated and whether there has been a zero crossing. If the second mask procedure is not activated and there is a zero crossing, the seek operation is completed and a track following operation is initiated in step 184. While the invention has been particularly shown and described with reference to preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.
In an optical disk recorder, during the sensing of closely-spaced, position-indicating, machine-sensible indicia, a first peak of a track error signal is detected. In response to the first peak being detected, a half-track counter is decremented from a value which depends upon the position of the destination track relative to a current track. In response to the occurrence of a selected value of the half-track counter and the presence of a zero crossing of the tracking error signal, a first timer is activated to mask any defects occurring during the selected first half cycle of the last cycle of the tracking error signal. The half-track counter is again decremented in response to a second peak being detected and the occurrence of a next-to-last zero crossing of the tracking error signal and a second timer is then activated to mask any subsequent defects occurring during the second half cycle of the tracking error signal. The seek operation is terminated when the count value in the half-track counter equals zero and a final zero crossing is detected. Thereafter, a track following operation is activated.
Provide a concise summary of the essential information conveyed in the context.
[ "This is a continuation of U.S. application Ser.", "No. 08/026,239, filed Mar. 1, 1993, now abandoned, which is a continuation of U.S. application Ser.", "No. 07/780,6654 filed Oct. 18, 1990, now abandoned.", "FIELD OF THE INVENTION The present invention relates to position control system, particularly those position systems being advantageously used with optical disk recorders.", "BACKGROUND OF THE INVENTION Both magnetic and optical disk recorders employ either a 14 large plurality of concentric record tracks or a single spiraling record track.", "The tracks on optical disks are identified by any one of a plurality of surface configurations on the optical medium (disk).", "A common configuration is a disk-shaped medium having circularly concentric Groove or a single spiral groove, for indicating the location of the record tracks.", "In both magnetic and optical disks recorders, means are provided for faithfully following one of the addressed record tracks.", "When it is desired to scan a track other than a currently scanned track, a track seek operation is provided;", "that is, the track following is aborted and a track seek algorithm is initiated which causes the effective disconnection of the track following operation.", "When seeking from one track to another track, magnetic and optical recorder must keep track of its current track on the disk as well as the desired track.", "This is typically done using a tracking error signal (TES).", "Tracks are counted as a recording head is moved radially across the tracks between the current track and the desired track.", "As is well known in the art, during a seek operation, a light beam is moved along with the recording head radially across the tracks.", "As the light beam moves across the tracks, the TES appears as a sinusoidal or substantial sinusoidal waveform.", "The peaks of TES are produced at the cliffs between the tracks and grooves on the disk surface.", "In this manner, the tracks are one full cycle apart.", "The simplest method of determining position from the TES is to produce a pulse whenever the TES crosses a zero reference point and then count these pulses.", "This method, however, is susceptible to miscounting due to noise and disk defects.", "A superior method, which is used today, utilizes a plurality of TES detectors to indicate zero crossing points and positive and negative peaks.", "Two peaks of opposite polarities must be encountered before a track crossing is counted.", "This method allows for greater noise tolerance on the TES.", "However, media defects can still occasionally result in either the seek operation being too long, i.e. it missed counting a track, or the seek being too short, i.e. counting a defect as a track.", "As is known in the art, both of these conditions can be recovered from quickly and easily.", "The only time a defect can cause a serious problem is when it occurs at the end of the seek operation when a tracking servo is activated.", "The tracking servo attempts to maintain the TES at the zero reference point.", "If the tracking servo is activated on a upward slope of the TES when the seeking operation is in a direction toward an outer edge of the disk, the tracking servo will lock on the target track.", "If, however, the tracking servo is activated on the downward slope, the TES would be opposite to what is needed for a stable condition.", "Thus, the recording head will "skate"", "over the disk.", "In essence, the head will move at an accelerated pace during the downward slope and decelerate over the upward slope.", "As a result of this activity, a time consuming recovery procedure must activated to stop the skating motion and to lock on the target track.", "Thus, it is important to activate the tracking servo on the correct slope after a seek operation.", "U.S. Pat. No. 4,839,876 discloses an optical disk recorder which includes a position servo control loop for causing a beam of radiation to faithfully follow a track on the disk, jump from a current track to an adjacent track or to a small number of tracks away from the current track.", "Operation of the position servo loop is altered by selectively reversing the phase of a differentiated position error signal and integrating the differentiated position error signal for comparison with a sawtooth signal for moving the beam of radiation from the current track to an immediately adjacent track under continuous position servo control.", "Upon reaching the adjacent track, the sawtooth signal returns to a reference potential for initiating track following.", "The servo error signal and the sawtooth signal does not cause any significant perturbations in the positioning servo loop operation.", "This patent does not address the problem encountering media defects during a seek operation.", "U.S. Pat. No. 5,038,333 discloses a track-seeking apparatus of a disk recorder which employs a track-crossing sensor to produce track-crossing signals.", "An oscillator is slaved to the sensor for supplying substitute track-crossing pulses in the absence of the sensor providing such pulses or when the radial velocity exceeds a threshold velocity.", "A velocity profile means alters the oscillator frequency so that the oscillator produces track-crossing pulses in accordance with the profile.", "This patent does not address the problem of the encountering media defects during a seek operation.", "U.S. Pat. No. 5,001,732 discloses a track counter for optical disk which counts the number of tracks a light beam passes upon when an optical head moves over an optical disk in a radial direction.", "The track counter includes a passage signal generating circuit which generates a signal each time the reflected light of the the light beam passes over a track.", "A counter counts the signals generated by the passage signal generating circuit.", "A counter suspending circuit determines that the light beam will pass over a specific position of a track and suspends the action of the counter for a predetermined period of time.", "A count value compensating circuit assumes the number of tracks the light beam passed during the predetermined period of time and adds this assumed number to the count value of the counter.", "This invention address problems on the disk in designated areas.", "It does not address the problem of encountering media defects which may occur in areas other than the designated areas.", "Accordingly, it is desired to provide for a drive which is less susceptible to poor optical media quality and provides for more reliability during seek operations.", "SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved positioning system having enhanced track counting and accommodation of defects during track seeking operations.", "In an optical disk recorder, during the sensing of closely-spaced, position-indicating, machine-sensible indicia, a first peak of a track error signal is detected.", "In response to the first peak being detected, a half-track counter is decremented from a value which depends upon the position of the destination track relative to a current track.", "In response to the occurrence of a selected value of the half-track counter and the presence of a zero crossing of the tracking error signal, a first timer is activated to mask any defects occurring during the selected first half cycle of the last cycle of the tracking error signal.", "The half-track counter is again decremented in response to a second peak being detected and the occurrence of a next-to-last zero crossing of the tracking error signal and a second timer is then activated to mask any subsequent defects occurring during the second half cycle of the tracking error signal.", "The seek operation is terminated when the count value in the half-track counter equals zero and a final zero crossing is detected.", "Thereafter, a track following operation is activated.", "The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a simplified block diagram of an optical disk recorder/player in accordance with the present invention.", "FIG. 2 spatially illustrates the relationship of tracks and tracking error signals.", "FIG. 3 is a waveform illustrating a defect occurring during a second half cycle of the last cycle of a tracking error signal.", "FIG. 4 is a block diagram of a circuit for masking the type of defect shown in FIG. 3 in accordance with the present invention.", "FIG. 5 is a waveform illustrating a defect occurring during the first and second half cycles of the last cycle of a tracking error signal.", "FIG. 6 is a block diagram of a circuit for masking the types of defects shown in FIG. 5 in accordance with the present invention.", "FIG. 7 is a flow chart illustrating the steps utilized in masking the defects shown in FIGS. 3 and 5.", "DETAILED DESCRIPTION Referring now more particularly to the appended drawing, like numerals indicate like structural parts and features in the various figures.", "An optical recorder with which the present invention may be advantageously employed is shown in FIG. 1. A magnetooptic record disk 30 is mounted on spindle 31 for rotation by motor 32.", "Optical head-carrying arm 33 on head-arm carriage generally denoted by numeral 34, moves radially of disk 30.", "A frame 35 of recorder suitably mounts carriage 34 for reciprocating radial motions.", "The radial motions of carriage 34 enable access to any one of a plurality of concentric tracks or circumvolutions of a spiral track for recording and recovering data on and from the disk.", "Linear actuator 36 suitably mounted on frame 35, radially moves carriage 34 for enabling track accessing.", "The recorder is suitably attached to one or more host processors 37, such host processors may be control units, personal computers, large system computers, communication systems, image process processors, and the like.", "Attaching circuits 38 provide the logical and electrical connections between the optical recorder and the attaching host processors 37.", "Microprocessor 40 controls the recorder including the attachment to the host processor 37.", "Control data, status data, commands and the like are exchanged between attaching circuits 38 and microprocessor 40 via bidirectional bus 43.", "Included in microprocessor 40 is a program or microcode storing, read-only memory (ROM) 41 and a data and control signal storing random access memory (RAM) 42.", "The optics of the recorder include an objective or focussing lens 45 mounted for focussing and tracking motions on head-arm 33 by fine actuator 46.", "This actuator includes mechanisms for moving lens 45 toward and away from disk 30 for focussing and for radial movements parallel to carriage 34 motions;", "for example, for changing tracks within a range of 100 tracks so that carriage 34 need not be actuated each time a track adjacent to a track currently being accessed is to be accessed.", "Numeral 47 denotes a two-way light path between lens 45 and disk 30.", "In magnetooptic recording, magnet 48 (in a constructed embodiment magnet 48 is an electromagnet) provides a weak magnetic steering field for directing the remnant magnetization direction of a small spot on disk 30 illuminated by laser light from lens 45.", "The laser light spot heats the illuminated spot on the record disk to a temperature above the Curie point of the magnetooptic layer (not shown, but can be an alloy of rare earth and transitional metals as taught by Chaudhari et al.", ", U.S. Pat. No. 3,949,387).", "This heating enables magnet 48 to direct the remnant magnetization to a desired direction of magnetization as the spot cools below the Curie point temperature.", "Magnet 48 is shown as oriented in the "write"", "direction, i.e., binary ones recorded on disk 30 normally are "north pole remnant magnetization".", "To erase disk 30, magnet 48 rotates so the south pole is adjacent disk 30.", "Magnet 48 control 49, which is mechanically coupled to rotatable magnet 48 as indicated by dashed line 50, controls the write and erase directions.", "Microprocessor 40 supplies control signals over line 51 to control 49 for effecting reversal of the recording direction.", "It is necessary to control the radial position of the beam following path 47, such that a track or circumvolution is faithfully followed and that a desired track or circumvolution is quickly and precisely accessed.", "To this end, focus and tracking circuits 54 control both the coarse actuator 36 and fine actuator 46.", "The positioning of carriage 34 by actuator 36 is precisely controlled by control signals supplied by circuits 54 over line 55 to actuator 36.", "Additionally, circuits 54 control signals travel over lines 57 and 58, respectively, for focus and fine tracking and switching actions of fine actuator 46.", "Lines 57, 58 respectively carry a position error signal to circuits 54 and a position control signal from circuits 54 to the focus and tracking mechanisms of actuator 46.", "Sensor 56 senses the relative position of fine actuator 46 to head-arm carriage 33.", "The focus and tracking position sensing is achieved by analyzing laser light reflected from disk 30 over path 47, thence through lens 45, through one-half mirror 60 and to be reflected by half-mirror 61 to a so-called "quad detector"", "62.", "Quad detector 62 has four photo elements which respectively supply signals on four lines collectively denominated by numeral 63 to focus and tracking circuits 54.", "Aligning one axis of the detector 62 with a track center line, track following operations are enabled.", "Focussing operations are achieved by comparing the light intensities detected by the four photo elements in the quad detector 62.", "Focus and tracking circuits 54 analyze the signals on lines 63 to control both focus and tracking.", "Recording or writing data onto disk 30 is next described.", "It is assumed that magnet 48 is rotated to the desired position for recording data.", "Microprocessor 40 supplies a control signal over line 65 to laser control 66 for indicating that a recording operation is to ensue.", "This means that laser 67 is energized by control 66 to emit a high-intensity, laser light beam for recording;", "in contrast, for reading, the laser 67 emitted laser light beam is a reduced intensity for not heating the laser illuminated spot on disk 30 above the Curie point.", "Control 66 supplies its control signal over line 68 to laser 67 and receives a feedback signal over line 69 indicating the laser 67 emitted light intensity.", "Control 68 adjusts the light intensity to the desired value.", "Laser 67, a semiconductor laser such as a gallium arsenide diode laser, can be modulated by data signals so the emitted light beam represents the data to be recorded by intensity modulation.", "In this regard, data circuits 75 (later described) supply data-indicating signals over line 78 to laser 67 for effecting such modulation.", "This modulated light beam passes through polarizer 70 (linearly polarizing the beam), thence through collimating lens 71 toward half mirror 60 for being reflected toward disk 30 through lens 45.", "Data circuits 75 are prepared for recording by the microprocessor 40 supplied control signals over line 76.", "Microprocessor 40 in preparing circuits 75 is responding to commands for recording received from a host processor 37 via attaching circuits 38.", "Once data circuits 75 are prepared, data is transferred directly between host processor 37 to data circuits 75 through attaching circuits 38.", "Data circuits 75 also includes ancillary circuits (not shown) relating to disk 30 format signals, error detection and correction and the like.", "Circuits 75, during a read or recovery action, strip the ancillary signals from the readback signals before supply corrected data signals over bus 77 to host processor 37 via attaching to 38.", "Reading or recovering data from disk 30 for transmission to a host processor requires optical and electrical processing of the laser light beam from the disk 30.", "That portion of the reflected light (which has its linear polarization from polarizer 70 rotated by disk 30 recording using the Kerr effect) travels along the two-way light path 47, through lens 45 and half-mirrors 60 and 61 to the data detection portion 79 of the head-arm 33 optics.", "Half-mirror or beam splitter 80 divides the reflected beam into two equal intensity beams both having the same reflected rotated linear polarization.", "The half-mirror 80 reflected light travels through a first polarizer 81, which is set to pass only that reflected light which was rotated when the remnant magnetization on disk 30 spot being accessed has a "north"", "or binary one indication.", "This passed light impinges on photo cell 82 for supplying a suitable indicating signal to differential amplifier 85.", "When the reflected light was rotated by a "south"", "or erased pole direction remnant magnetization, then polarizer 81 passes no or very little light resulting in no active signal being supplied by photocell 82.", "The opposite operation occurs by polarizer 83 which passes only "south"", "rotated laser light beam to photo cell 84.", "Photocell 84 supplies its signal indicating its received laser light to the second input of differential amplifier 85.", "The amplifier 85 supplies the resulting difference signal (data representing) to data circuits 75 for detection.", "The detected signals include not only data that is recorded but also all of the so-called ancillary signals as well.", "The term "data"", "as used herein is intended to include any and all information-bearing signals, preferably of the digital or discrete value type.", "The rotational position and rotational speed of spindle 31 is sensed by a suitable tachometer or emitter sensor 90.", "Sensor 90, preferably of the optical sensing type that senses dark and light spots on a tachometer wheel (not shown) of spindle 31, supplies the "tach"", "signals (digital signals) to RPS circuit 91 which detects the rotational position of spindle 31 and supplies rotational information-bearing signals to microprocessor 40.", "Microprocessor 40 employs such rotational signals for controlling access to data storing segments on disk 30 as is widely practiced in the magnetic data storing disks.", "Additionally, the sensor 90 signals also travel to spindle speed control circuits 93 for controlling motor 32 to rotate spindle 31 at a constant rotational speed.", "Control 93 may include a crystal controlled oscillator for controlling motor 32 speed, as is well known.", "Microprocessor 40 supplies control signals over line 94 to control 93 in the usual manner.", "Referring to FIG. 2, a portion of the information-bearing surface of disk 30 is illustrated.", "The disk 30 is formed with two sets of concentric rings, one set being tracks or mesas 100 and the second set being grooves 102.", "When the light beam 47 is focused into a groove 102, the TES is at a zero crossing position 104, i.e. when exactly centered, the sensed TES should be at zero.", "As the light beam 47 moves from one track to another track, the amplitude of TES changes as a sinusoid with the direction of change indicating the direction of tracking error.", "As the light beam 47 scans transversely (radially) across the tracks 100 or grooves 102, TES takes the sinusoidal shape wherein zero axis crossings in a first direction signify crossing the center of the grooves.", "Similarly, when the light beam 47 is crossing the tracks 100, the zero access crossing of TES is in the opposite direction.", "In essence, the peaks of TES are produced at the cliffs between the tracks 100 and the grooves 102 on the surface of the disk 30.", "FIG. 3 illustrates a portion of a TES signal 110 wherein a defect 112 occurs during the last half cycle of the signal.", "It is understood that a seek in an opposite direction would invert the polarity of the TES and its slope in the discussion to follow.", "As stated above, one method of minimizing the susceptibility of the optical recorder to noise and disk defects is to use three TES detectors (not shown).", "These detectors indicate when the TES crosses a zero reference point and the positive peaks and the negative peaks of TES.", "Two peaks of opposite polarities must be encountered before a track is counted.", "Further as noted above, the TES signal 110 is sinusoidal whose positive peak exceeds a positive threshold 116 and whose negative peak exceeds a negative threshold 118.", "The positive and negative peaks of TES signal 110 must exceed the respective thresholds 116 and 118 in order to be considered a peak during a seek operation.", "Moreover, the TES signal 110 normally crosses a zero reference point 114 between positive and negative peaks.", "At the conclusion of a seek operation, a track servo (not shown) is activated to continue a track following operation on the desired track.", "Detail of the tracking circuits are disclosed in U.S. Pat. No. 5,038,333 which issued to W. W. Chow et al, assigned to the assignee of the present case and is hereby incorporated herein by reference.", "During the second half cycle of the last cycle of the TES signal 110, the defect 112 causes the detection of a negative pulse which exceeds the negative threshold 118 and could be interpreted as a zero crossing.", "The tracking servo normally activates after sequence of a positive pulse, a first zero crossing, a negative pulse and a second zero crossing.", "Moreover, if the tracking servo activates on an upward slope of the TES signal 110 after encountering the above sequence, it will be in a stable condition and will successfully lock onto the desired track.", "In view of the defect 112, the sequence includes a positive pulse, a first zero crossing, a negative pulse and a second zero crossing.", "However, the slope of the TES signal 110 is downward which cause an unstable condition when the tracking servo activates and causes a error in a subsequent track following operation.", "FIG. 4 shows a block diagram of a masking circuit 130 which eliminates the error caused by the defect 112 (FIG.", "3) encountered during the last half cycle of the TES signal 110.", "Circuit 130 includes a half-track counter 132.", "Prior to a seek operation, counter 132 is loaded with a count value which is equal to the number of half-tracks between the present track and the desired track.", "For purposes of illustration and not limitation, if a seek operation to be executed involves a movement to a track which is two tracks away from the current track, the count value in counter 132 is set equal to a value of four which coincides to four half-tracks.", "Thereafter, counter 132 is decremented one count for each half-track of movement.", "As is shown in FIG. 3, one half-track is equal to one half cycle of the TES signal 110.", "Circuit 130 further includes an AND gate 134 which receives an indication when the TES signal 110 performs a zero crossing and and input from a decoder/comparator 136.", "Comparator 136 compares the count value of the counter 132 with a value of one.", "Gate 134 is coupled to a timer circuit 138.", "The timer circuit 138 is coupled to the seek control logic 140.", "The details of the timer circuit and the seek control logic are well known in the art and will not be discussed here.", "In operation, during a seek operation, the optical recorder will always arrive at the destination or desired track with a constant velocity plus or minus some tolerance.", "Thus, any defect that may occur during the downward slope of the last peak can be masked out.", "The timer circuit 138 is activated upon the occurrence of the next-to-last zero crossing of the TES signal 110 and a count value of one in the counter 132.", "The next-to-last zero crossing of the TES signal 110 occurs when the count value of the counter 132 equals a value of one and zero crossing of the TES signal occurs.", "The activation of timer circuit 138 facilitates the blocking of the final zero crossing point of the TES signal 110 for a predetermined time.", "The timer circuit 138 must have a time interval which is equal to the time required to reach a last peak immediately prior to the required time to terminate the seek operation.", "FIG. 5 illustrates a TES signal 110'", "wherein a defect 150 occurs in the first half cycle and a defect 152 occurs during the second half cycle of the signal.", "The TES signal 110'", "is sinusoidal whose positive peak exceed a positive threshold 116'", "and whose negative peak exceed a negative threshold 118'.", "The positive and negative peaks of TES signal 110'", "must exceed the respective thresholds 116'", "and 118'", "in order to be considered a peak during a seek operation.", "Moreover, the TES signal 110'", "normally crosses a zero reference point 114'", "between positive and negative peaks.", "Although defect 150 is slightly different from defect 112, the same techniques can be used to resolve the media defect condition.", "As illustrated in FIG. 5, defect 150 goes beyond the threshold point 118'", "and would appear as a true track crossing.", "With this condition, the normal seek algorithm would be fooled into activating the tracking servo on the wrong slope of the TES signal 110'.", "Moreover, as set forth above, in view of the constant and predictable velocity (within a specific tolerance) at the end of the seek operation, it can be predicted, using a masking circuit similar to circuit 130, that the last peak caused by defect 150 comes well before the predicted time.", "FIG. 6 illustrates a block diagram of a masking circuit 160 which eliminates the errors caused by the defects 150 and 152 (FIG.", "5).", "Circuit 160 includes a half-track counter 132'.", "Prior to a seek operation, counter 132'", "is loaded with a count value which is equal to the number of half-tracks between the present track and the desired track.", "For purposes of illustration and not limitation, if a seek operation to be executed involves a movement to a track which is two tracks away from the current track, the count value in counter 132'", "is set equal to a value of four which coincides to four half-tracks.", "Thereafter, counter 132'", "is decremented one count for each half-track of movement.", "Circuit 160 further includes an AND gate 134'", "which receives an indication when the TES signal 110'", "performs a zero crossing and an input from a decoder/comparator 136'.", "Comparator 136'", "compares the count value of the counter 132'", "with values of one and two.", "AND gate 134'", "is coupled to a first timer circuit 138'.", "The first timer circuit 138'", "is coupled an input of an AND gate 139.", "AND gates 134'", "and 139 each receive an input from the comparator 136'", "and an indication when a zero crossing has occurred.", "AND gate 139 is coupled to a second timer circuit 144.", "The second timer circuit 144 is coupled to the seek control logic 148.", "The details of the timer circuits 138'", "and 144, and the seek control logic 148 are well known in the art and will not be discussed here.", "In operation, during a seek operation, the optical recorder will always arrive at the destination or desired track with a constant velocity plus or minus some tolerance.", "Thus, any defect that may occur during the downward slope of the last peak can be masked out.", "The first timer circuit 138'", "is activated upon the occurrence of the zero crossing of the TES signal 110'", "and when the count value of the half-track counter 132'", "equals two.", "The count value of two in the half-track counter 132'", "represents either the first half cycle of the TES signal 110'", "if the destination track is the next adjacent track or the first half cycle of the last track prior to the destination track.", "The activation of the first timer circuit 138'", "facilitates the blocking of the defect 150 of the TES signal 110'", "for a predetermined time.", "The first timer circuit 138'", "must have a time interval which is equal to the time required to reach beyond the expected passing of threshold 116'", "but prior to the next-to-last zero crossing point 145 (FIG[.", "].5).", "When the first timer 138'", "has timed-out, it sends a signal to AND gate 139.", "Upon the occurrence of a count value of one in the half-track counter 136'", "and that of the next-to-last zero crossing point, the second timer circuit 144 is activated to mask out the defect 152 in a similar manner set forth above for defect 112.", "FIG. 7 is a flow chart which illustrates the steps utilized in masking out media defects encountered during a seek operation in accordance with the present invention.", "In step 170, prior to initiating the seek operation, the half-track counter 132 or 132'", "are loaded with the appropriate count value reflective of the number of half-tracks between the current track and the destination or desired track.", "Step 172 determines whether a first peak has been detected.", "Step 174 decrements the half-track counter 132 or 132'", "subsequent to the detection of the first peak.", "Step 176 determines whether a second peak has been detected and whether the first mask procedure has not been activated.", "Step 178 facilitates the decrementing of the half-track counter 132 or 132'", "in response to the second peak being detected and the first mask procedure not being activated.", "Step 180 determines whether the half-track counter 132 or 132'", "has reached a count of zero.", "Step 182 determines whether the second mask procedure is activated and whether there has been a zero crossing.", "If the second mask procedure is not activated and there is a zero crossing, the seek operation is completed and a track following operation is initiated in step 184.", "While the invention has been particularly shown and described with reference to preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention." ]
This is a division of application Ser. No. 833,293, filed Feb. 25, 1986, now U.S. Pat. No. 4,723,876. BACKGROUND OF THE INVENTION Frequently, large structures, such as offshore platforms, are anchored to the earth with tubular piles. Those piles are inserted through structural members of the platform and driven into the earth. They are then attached or "grouted" to the structural member. Often, these piles extend several hundred feet into the earth. The length, number, and size of the pilings are in large part determined by the type of soil through which the piles are driven. Characteristics of the soil are normally determined before fabrication of the structure by analysis of soil samples or by other means. Unfortunately, in some cases, the soil characteristics are inaccurately predicted and it is found that the as-driven piles provide inadequate support for the structure after the structure is installed. On other occasions, the soil qualities can be accurately determined, but it may be desirable to enhance the load capability of the piling. In still other cases, the structure is installed in permafrost and the frozen condition of the soil must be maintained to prevent settling of the structure. Various methods of increasing or maintaining the load-bearing capacity of piles have been developed. For example, "anchor bumps" can be created on the pile to increase the load-bearing capacity and pull out resistance of the pile (U.S. Pat. No. 3,995,438). In some cases this may, however, not sufficiently increase the capacity of the pile. Methods of maintaining the frozen condition of the soil have also been described (French Pat. No. 475,226, see also U.S. Pat. No. 4,111,258). These methods rely on the circulation of cold ambient air through the pile to maintain the frozen condition of the soil. Such methods could not be applied in an area where extremely cold ambient conditions do not exist for a substantial portion of the year. Further, they provide only for the maintenance of the soil in the frozen condition to prevent subsidence and do not provide increased pull-out capacity. Ground freezing has been used in order to provide temporary structural support while installing a subterranean tunnel, to prevent settling of a runway set on permafrost, and to prevent water encroachment during the installation of a ventilation shaft (Braun, B., and Nash, W. R., "Ground Freezing for Construction", Civil Engineering, Jan., 1985, pp 54-56). In none of the above situations is a permanent method of substantially increasing the loadbearing and pull-out capacity of a tubular pile provided. In summary, it is clear that an improved method of substantially enhancing the load-bearing and pull-out capacity of a pile is desirable. BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention provides a means and method for increasing the capacity of tubular piles by freezing one or more areas of soil surrounding the piles. The invention would be used where a tubular pile, whose design capacity was to be provided through shaft friction, is incapable of supporting design loads because adequate shaft friction cannot be developed, or where the frozen condition of soil surrounding the pile must be maintained to prevent settling. The preferred embodiment features a sealed, cone-shaped refrigeration unit which is lowered into the pile of an offshore platform. Below the refrigeration unit, the pile is filled with a brine solution (such as calcium chloride), the bottom of the pile being sealed with a concrete plug. Seawater fills the pile above the refrigeration unit and is allowed to commingle with seawater above the mud-line. The refrigeration unit forms a tight seal in the pile to prevent commingling of the seawater above the unit and the brine below the unit and serves as a thermal barrier between the seawater and the brine. The refrigeration unit consists of from 1 to 3 motor-driven refrigeration compressors of the type commonly known to one skilled in the art. In the preferred embodiment, 3 compressors each having a capacity of from 10 to 20 horsepower are installed in each refrigeration unit. This would be sufficient to cool the brine to approximately -20° to --30° C. The condenser for the refrigeration unit protrudes into the seawater above the refrigeration unit and the seawater provides condensor cooling. Seawater circulates within the pile by natural convection. The refrigeration evaporator and expansion tank extend into and cool the brine solution. In turn, the brine cools and eventually freezes the in-situ pore water surrounding the pile and eventually the adjacent soil sediments thus forming a large frozen soil mass. The net result is that the pile has greatly increased capacity against downward and pull-out load applications. The major components contributing to this increased capacity are the increased side friction and end bearing between the frozen and unfrozen soil masses, both being transferred through the indirect adfreeze bond between the steel pile and surrounding soil. OBJECTS OF THE INVENTION It is the particular object of the invention to provide a method of increasing or maintaining the load bearing capacity of a tubular pile by freezing and/or maintaining the frozen condition of soil in an area surrounding the pile. It is a further object of the invention to provide the apparatus and by which the soil surrounding a pile can be frozen and/or maintained in a frozen condition. It is a further object of the invention to provide the method and apparatus for installing and maintaining a down-pile, pile shaft freezing apparatus. Additional objects and advantages of the present invention will become apparent from reading the following detailed description in view of the accompanying drawings which are made part of this specification. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts an offshore platform with a detailed cross section of one pile into which a refrigeration unit has been installed; FIG. 2 is a cross section of the refrigeration unit which generally depicts the flow of refrigerant through the system and the circulation of brine and seawater in the pile; FIG. 3 is a cross section of a refrigeration unit showing details of the internal components of the refrigeration unit; FIG. 4 shows three top plan views of the refrigeration unit at the top level, middle level, and bottom level; FIG. 5 shows a cross section of the manner in which the refrigeration unit is lowered into the pile; FIG. 6 shows a cross section of the refrigeration unit after being lowered into its final position within the pile; FIG. 7 shows a cross section of the umbilical as it is pulled by a work boat; and FIG. 8 shows a cross section of the umbilical tied to a marker buoy. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 generally illustrates the concept of down-pile foundation pile shaft freezing in the preferred embodiment. In this embodiment, sealed refrigeration units 1 are placed inside the tubular pilings 2 of an offshore platform 3 a predetermined distance above a bottom brine seal, which is a concrete plug 4 in the preferred embodiment. The area between the refrigeration unit 1 and the cement plug 4 is filled with CaCl 2 or a similar secondary refrigerant 5 which has a freezing point sufficiently lower than the water contained within the soil surrounding the pile. Although CaCl 2 is described in the preferred embodiment, other secondary refrigerants may be used depending on the design operating temperature which will account for factors such as the necessary adfreeze strength, soil property variations with temperature, and other factors. Various secondary refrigerants are well-known in the art. For example, ethylene glycol, or alcohol/water mixtures might also be used. Seawater 6 is allowed to freely enter and leave the pile 2 above the refrigeration unit 1. The refrigeration unit 1 forms a tight seal with the pile 2 which prevents commingling of the seawater above the refrigeration unit and the brine below the refrigeration unit and serves to thermally insulate the cold brine and ambient seawater Each refrigeration unit 1 is provided with power from the platform 3 from an umbilical 7. The umbilicals from the various piles are routed through a common caisson 8 on each platform leg 9. These caissons are routed through the jacket pile installation guides 10. Instrumentation lines (not shown) are also included in the umbilical lines. FIG. 2 illustrates generally the operation of the refrigeration unit. Identical pieces of equipment from FIG. 1 are identically numbered Refrigerant of a type commonly used in the art (propane in the preferred embodiment) is compressed in the refrigeration compressor 11 and warm, compressed refrigerant flows into a falling film condenser 12 where heat is transferred to the surrounding, cooler seawater 6 and the refrigerant condenses. Refrigerants other than propane are well-known to one skilled in the art and could also be utilized (for example, ammonia) As the seawater is warmed, it becomes buoyant and rises in the piling [illustrated by arrows 13]. Cooler seawater displaces the warm seawater so that the area surrounding the condenser remains cool [illustrated by arrows 14]. The condensed refrigerant passes through an expansion valve 15 to a low pressure evaporation tank 16 and evaporator 17. As the refrigerant boils, it absorbs energy from the brine in the evaporator and the brine 5 cools. The brine, like the seawater, is circulated by natural convection, i.e., as the brine is cooled it falls and is replaced by warmer brine. As heat is transferred from the surrounding soil 18 to the brine, the soil cools and the pore water contained within the soil freezes. Eventually, a large frozen mass of soil 19 surrounding the pile is formed. The size of this frozen mass and rate of formation can be determined from thermodynamic calculations familiar to one skilled in the art. Adhesive friction between the tubular pile and the frozen soil [depicted by arrow 20] is significantly greater than shaft friction between a tubular pile and unfrozen soil [depicted by arrow 21]. Provided adfreeze strength between the tubular pile and frozen soil is sufficiently strong to transfer loading, the frozen mass surrounding the pile provides increased support because: (1) Side friction area, with time after initiation of freezing, available to transfer loading into the native unfrozen soil mass is much greater than that available without freezing, thus allowing increased support capability; and (2) End bearing area formed due to the freezing process forms an additional support component (depicted by arrows 22) contributing to increased foundation capacity over that provided by the pile alone (depicted by arrows 23). Power and instrumentation lines for the refrigeration unit enter the refrigeration unit through the umbilical 7. Insulation 24 is provided around the refrigeration unit to prevent freezing of the seawater from indirect contact with the brine. Packers 25 and grout 26 hold the unit in place. Greater detail regarding the refrigeration units is provided in FIGS. 3 and 4. Again, identical pieces of equipment are identically numbered with FIGS. 1 and 2. FIG. 4 is a cutaway planar view of the refrigeration unit. The far left section 27 is a view beneath the refrigeration unit in the brine bath. The far right section 28 is a view within the refrigeration unit. The top section 29 is a view of the top of the refrigeration unit at the seawater level. It should be noted that one or more refrigeration compressors may be included within a single refrigeration unit. FIG. 4 illustrates the arrangement of equipment that would be appropriate for a refrigeration unit having 3 compressors (a "triplex" system), but the claims are not so limited. The advantage of using 3 compressors are: (1) It provides high the start-up capacity necessary to freeze the soil; and (2). It provides back-up compressors after the soil is frozen and it becomes unnecessary to run all three compressors. The main body of the refrigeration unit consists of a sealed, tapered, steel vessel 30 which fits within the tubular pile. The vessel contains one or more hermetically sealed compressors 11 driven by electric motors 32. An insulation barrier is provided around the the vessel 24. The vessel is tapered to allow for the flow of fluids around it as it is raised and lowered into the pile. The vessel contains ballast weights 33 which provide neutral buoyancy for the entire package. The vessel is grouted to the pile to hold it in place, but in the event that the unit would need to be removed, the tapered shape would result in less effort to break the grout. The effort required to remove the refrigeration unit from the pile is further reduced by coating the vessel with a bond breaking agent. An evaporator 17 and refrigerant tank 16 are suspended beneath the vessel for each refrigeration compressor in the unit. The condenser discharge line 34, expansion valve 15 and compressor suction line all protrude through the top of the refrigerant tank. The compressor is provided with protection from liquids which are well known in the art (not shown). The condenser 12 is mounted on top of the vessel. The compressor is equipped with a cooling water jacket 36 which circulates warm water to a jacket water cooler 37 which is also mounted on top of the vessel and is cooled with seawater contained within the pile. To provide protection to the exposed portions of the refrigeration unit during installation and maintenance, an upper tripod frame 38 and a lower tripod frame 39, constructed of tubular steel members, are attached to the top and bottom of the vessel, respectively. The upper tripod frame also serves as an attachment point for the drill string used in installation/removal of the unit. Installation of the refrigeration unit is illustrated in FIGS. 5 through 8. Referring first to FIG. 5, pile guides 10 adjacent to the jacket legs 9 are used as guides to lower the refrigeration unit 1 into position. A work-over rig 40 or similar structure is used to lower the refrigeration unit into place. A drill string 41 of the type commonly used in oil well drilling operations can be used to suspend the refrigeration unit. Centralizers 42 and a submersible vehicle 43 may also be used to help guide the refrigeration unit into place. Referring to FIG. 6, the umbilical, grout and packer hoses 43 are held to the drill string with clamps 44 and lowered with the refrigeration unit. When the refrigeration unit reaches the pile 2, it is inserted into the pile and lowered to the proper level. A quick disconnect 45 is inserted in the drill string so that the final position of the quick disconnect will be slightly above the top of the pile. When the unit is lowered to the correct elevation, brine solution is pumped down the drill string. Since the density of the brine is greater than that of the seawater, the brine displaces seawater in the lower portion of the pile. Packers 25 are then set and the annulus between the vessel and the pile is pumped with grout 26. The wall of the vessel is precoated with a bond-breaking agent so that the vessel may be broken free of the grout should retrieval be necessary. After the grout has set, the drill string is broken with the quick disconnect. The drill string, grout and packer hoses are then retrieved. Referring to FIG. 7, a wire rope 46 from a work boat 47 is attached to a sliding thimble 48 located on the umbilical 48. The wire rope is used to pull the umbilical and preinstalled messenger line 49 out of the pile and lay it on the ocean floor 50. Referring to FIG. 8, the messenger line is pulled on deck of a work boat and attached to a marker buoy 51. Referring back to FIG. 1, caisson 8 is lowered along the jacket leg 9 and secured to the pile guides 10. A second messenger line is lowered through the caisson, passed to the work boat, and the umbilical is pulled through the caisson. This procedure is followed for each of the piles on the platform. Power and instrumentation are then connected to the umbilicals and the system is placed in operation. While certain specific embodiments of the invention have been described in detail, the invention is not to be limited to these embodiments, but rather by the scope of the appended claims.
The invention relates to a method and apparatus for increasing the capacity of a tubular driven pile. A refrigeration unit is lowered into the pile and grouted in place above a cement plug. The area between the refrigeration unit and the plug is filled with a secondary refrigerant. Seawater fills the pile above the refrigeration unit and is used for refrigeration unit cooling. The refrigeration unit cools the brine until the soil surrounding the pile is frozen. The adfreeze strength of the frozen soil and the pile increase the pullout resistance of the pile. Further, the end-bearing capacity of the pile is increased as a result of the large frozen mass surrounding the pile.
Briefly describe the main idea outlined in the provided context.
[ "This is a division of application Ser.", "No. 833,293, filed Feb. 25, 1986, now U.S. Pat. No. 4,723,876.", "BACKGROUND OF THE INVENTION Frequently, large structures, such as offshore platforms, are anchored to the earth with tubular piles.", "Those piles are inserted through structural members of the platform and driven into the earth.", "They are then attached or "grouted"", "to the structural member.", "Often, these piles extend several hundred feet into the earth.", "The length, number, and size of the pilings are in large part determined by the type of soil through which the piles are driven.", "Characteristics of the soil are normally determined before fabrication of the structure by analysis of soil samples or by other means.", "Unfortunately, in some cases, the soil characteristics are inaccurately predicted and it is found that the as-driven piles provide inadequate support for the structure after the structure is installed.", "On other occasions, the soil qualities can be accurately determined, but it may be desirable to enhance the load capability of the piling.", "In still other cases, the structure is installed in permafrost and the frozen condition of the soil must be maintained to prevent settling of the structure.", "Various methods of increasing or maintaining the load-bearing capacity of piles have been developed.", "For example, "anchor bumps"", "can be created on the pile to increase the load-bearing capacity and pull out resistance of the pile (U.S. Pat. No. 3,995,438).", "In some cases this may, however, not sufficiently increase the capacity of the pile.", "Methods of maintaining the frozen condition of the soil have also been described (French Pat. No. 475,226, see also U.S. Pat. No. 4,111,258).", "These methods rely on the circulation of cold ambient air through the pile to maintain the frozen condition of the soil.", "Such methods could not be applied in an area where extremely cold ambient conditions do not exist for a substantial portion of the year.", "Further, they provide only for the maintenance of the soil in the frozen condition to prevent subsidence and do not provide increased pull-out capacity.", "Ground freezing has been used in order to provide temporary structural support while installing a subterranean tunnel, to prevent settling of a runway set on permafrost, and to prevent water encroachment during the installation of a ventilation shaft (Braun, B., and Nash, W. R., "Ground Freezing for Construction", Civil Engineering, Jan., 1985, pp 54-56).", "In none of the above situations is a permanent method of substantially increasing the loadbearing and pull-out capacity of a tubular pile provided.", "In summary, it is clear that an improved method of substantially enhancing the load-bearing and pull-out capacity of a pile is desirable.", "BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention provides a means and method for increasing the capacity of tubular piles by freezing one or more areas of soil surrounding the piles.", "The invention would be used where a tubular pile, whose design capacity was to be provided through shaft friction, is incapable of supporting design loads because adequate shaft friction cannot be developed, or where the frozen condition of soil surrounding the pile must be maintained to prevent settling.", "The preferred embodiment features a sealed, cone-shaped refrigeration unit which is lowered into the pile of an offshore platform.", "Below the refrigeration unit, the pile is filled with a brine solution (such as calcium chloride), the bottom of the pile being sealed with a concrete plug.", "Seawater fills the pile above the refrigeration unit and is allowed to commingle with seawater above the mud-line.", "The refrigeration unit forms a tight seal in the pile to prevent commingling of the seawater above the unit and the brine below the unit and serves as a thermal barrier between the seawater and the brine.", "The refrigeration unit consists of from 1 to 3 motor-driven refrigeration compressors of the type commonly known to one skilled in the art.", "In the preferred embodiment, 3 compressors each having a capacity of from 10 to 20 horsepower are installed in each refrigeration unit.", "This would be sufficient to cool the brine to approximately -20° to --30° C. The condenser for the refrigeration unit protrudes into the seawater above the refrigeration unit and the seawater provides condensor cooling.", "Seawater circulates within the pile by natural convection.", "The refrigeration evaporator and expansion tank extend into and cool the brine solution.", "In turn, the brine cools and eventually freezes the in-situ pore water surrounding the pile and eventually the adjacent soil sediments thus forming a large frozen soil mass.", "The net result is that the pile has greatly increased capacity against downward and pull-out load applications.", "The major components contributing to this increased capacity are the increased side friction and end bearing between the frozen and unfrozen soil masses, both being transferred through the indirect adfreeze bond between the steel pile and surrounding soil.", "OBJECTS OF THE INVENTION It is the particular object of the invention to provide a method of increasing or maintaining the load bearing capacity of a tubular pile by freezing and/or maintaining the frozen condition of soil in an area surrounding the pile.", "It is a further object of the invention to provide the apparatus and by which the soil surrounding a pile can be frozen and/or maintained in a frozen condition.", "It is a further object of the invention to provide the method and apparatus for installing and maintaining a down-pile, pile shaft freezing apparatus.", "Additional objects and advantages of the present invention will become apparent from reading the following detailed description in view of the accompanying drawings which are made part of this specification.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts an offshore platform with a detailed cross section of one pile into which a refrigeration unit has been installed;", "FIG. 2 is a cross section of the refrigeration unit which generally depicts the flow of refrigerant through the system and the circulation of brine and seawater in the pile;", "FIG. 3 is a cross section of a refrigeration unit showing details of the internal components of the refrigeration unit;", "FIG. 4 shows three top plan views of the refrigeration unit at the top level, middle level, and bottom level;", "FIG. 5 shows a cross section of the manner in which the refrigeration unit is lowered into the pile;", "FIG. 6 shows a cross section of the refrigeration unit after being lowered into its final position within the pile;", "FIG. 7 shows a cross section of the umbilical as it is pulled by a work boat;", "and FIG. 8 shows a cross section of the umbilical tied to a marker buoy.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 generally illustrates the concept of down-pile foundation pile shaft freezing in the preferred embodiment.", "In this embodiment, sealed refrigeration units 1 are placed inside the tubular pilings 2 of an offshore platform 3 a predetermined distance above a bottom brine seal, which is a concrete plug 4 in the preferred embodiment.", "The area between the refrigeration unit 1 and the cement plug 4 is filled with CaCl 2 or a similar secondary refrigerant 5 which has a freezing point sufficiently lower than the water contained within the soil surrounding the pile.", "Although CaCl 2 is described in the preferred embodiment, other secondary refrigerants may be used depending on the design operating temperature which will account for factors such as the necessary adfreeze strength, soil property variations with temperature, and other factors.", "Various secondary refrigerants are well-known in the art.", "For example, ethylene glycol, or alcohol/water mixtures might also be used.", "Seawater 6 is allowed to freely enter and leave the pile 2 above the refrigeration unit 1.", "The refrigeration unit 1 forms a tight seal with the pile 2 which prevents commingling of the seawater above the refrigeration unit and the brine below the refrigeration unit and serves to thermally insulate the cold brine and ambient seawater Each refrigeration unit 1 is provided with power from the platform 3 from an umbilical 7.", "The umbilicals from the various piles are routed through a common caisson 8 on each platform leg 9.", "These caissons are routed through the jacket pile installation guides 10.", "Instrumentation lines (not shown) are also included in the umbilical lines.", "FIG. 2 illustrates generally the operation of the refrigeration unit.", "Identical pieces of equipment from FIG. 1 are identically numbered Refrigerant of a type commonly used in the art (propane in the preferred embodiment) is compressed in the refrigeration compressor 11 and warm, compressed refrigerant flows into a falling film condenser 12 where heat is transferred to the surrounding, cooler seawater 6 and the refrigerant condenses.", "Refrigerants other than propane are well-known to one skilled in the art and could also be utilized (for example, ammonia) As the seawater is warmed, it becomes buoyant and rises in the piling [illustrated by arrows 13].", "Cooler seawater displaces the warm seawater so that the area surrounding the condenser remains cool [illustrated by arrows 14].", "The condensed refrigerant passes through an expansion valve 15 to a low pressure evaporation tank 16 and evaporator 17.", "As the refrigerant boils, it absorbs energy from the brine in the evaporator and the brine 5 cools.", "The brine, like the seawater, is circulated by natural convection, i.e., as the brine is cooled it falls and is replaced by warmer brine.", "As heat is transferred from the surrounding soil 18 to the brine, the soil cools and the pore water contained within the soil freezes.", "Eventually, a large frozen mass of soil 19 surrounding the pile is formed.", "The size of this frozen mass and rate of formation can be determined from thermodynamic calculations familiar to one skilled in the art.", "Adhesive friction between the tubular pile and the frozen soil [depicted by arrow 20] is significantly greater than shaft friction between a tubular pile and unfrozen soil [depicted by arrow 21].", "Provided adfreeze strength between the tubular pile and frozen soil is sufficiently strong to transfer loading, the frozen mass surrounding the pile provides increased support because: (1) Side friction area, with time after initiation of freezing, available to transfer loading into the native unfrozen soil mass is much greater than that available without freezing, thus allowing increased support capability;", "and (2) End bearing area formed due to the freezing process forms an additional support component (depicted by arrows 22) contributing to increased foundation capacity over that provided by the pile alone (depicted by arrows 23).", "Power and instrumentation lines for the refrigeration unit enter the refrigeration unit through the umbilical 7.", "Insulation 24 is provided around the refrigeration unit to prevent freezing of the seawater from indirect contact with the brine.", "Packers 25 and grout 26 hold the unit in place.", "Greater detail regarding the refrigeration units is provided in FIGS. 3 and 4.", "Again, identical pieces of equipment are identically numbered with FIGS. 1 and 2.", "FIG. 4 is a cutaway planar view of the refrigeration unit.", "The far left section 27 is a view beneath the refrigeration unit in the brine bath.", "The far right section 28 is a view within the refrigeration unit.", "The top section 29 is a view of the top of the refrigeration unit at the seawater level.", "It should be noted that one or more refrigeration compressors may be included within a single refrigeration unit.", "FIG. 4 illustrates the arrangement of equipment that would be appropriate for a refrigeration unit having 3 compressors (a "triplex"", "system), but the claims are not so limited.", "The advantage of using 3 compressors are: (1) It provides high the start-up capacity necessary to freeze the soil;", "and (2).", "It provides back-up compressors after the soil is frozen and it becomes unnecessary to run all three compressors.", "The main body of the refrigeration unit consists of a sealed, tapered, steel vessel 30 which fits within the tubular pile.", "The vessel contains one or more hermetically sealed compressors 11 driven by electric motors 32.", "An insulation barrier is provided around the the vessel 24.", "The vessel is tapered to allow for the flow of fluids around it as it is raised and lowered into the pile.", "The vessel contains ballast weights 33 which provide neutral buoyancy for the entire package.", "The vessel is grouted to the pile to hold it in place, but in the event that the unit would need to be removed, the tapered shape would result in less effort to break the grout.", "The effort required to remove the refrigeration unit from the pile is further reduced by coating the vessel with a bond breaking agent.", "An evaporator 17 and refrigerant tank 16 are suspended beneath the vessel for each refrigeration compressor in the unit.", "The condenser discharge line 34, expansion valve 15 and compressor suction line all protrude through the top of the refrigerant tank.", "The compressor is provided with protection from liquids which are well known in the art (not shown).", "The condenser 12 is mounted on top of the vessel.", "The compressor is equipped with a cooling water jacket 36 which circulates warm water to a jacket water cooler 37 which is also mounted on top of the vessel and is cooled with seawater contained within the pile.", "To provide protection to the exposed portions of the refrigeration unit during installation and maintenance, an upper tripod frame 38 and a lower tripod frame 39, constructed of tubular steel members, are attached to the top and bottom of the vessel, respectively.", "The upper tripod frame also serves as an attachment point for the drill string used in installation/removal of the unit.", "Installation of the refrigeration unit is illustrated in FIGS. 5 through 8.", "Referring first to FIG. 5, pile guides 10 adjacent to the jacket legs 9 are used as guides to lower the refrigeration unit 1 into position.", "A work-over rig 40 or similar structure is used to lower the refrigeration unit into place.", "A drill string 41 of the type commonly used in oil well drilling operations can be used to suspend the refrigeration unit.", "Centralizers 42 and a submersible vehicle 43 may also be used to help guide the refrigeration unit into place.", "Referring to FIG. 6, the umbilical, grout and packer hoses 43 are held to the drill string with clamps 44 and lowered with the refrigeration unit.", "When the refrigeration unit reaches the pile 2, it is inserted into the pile and lowered to the proper level.", "A quick disconnect 45 is inserted in the drill string so that the final position of the quick disconnect will be slightly above the top of the pile.", "When the unit is lowered to the correct elevation, brine solution is pumped down the drill string.", "Since the density of the brine is greater than that of the seawater, the brine displaces seawater in the lower portion of the pile.", "Packers 25 are then set and the annulus between the vessel and the pile is pumped with grout 26.", "The wall of the vessel is precoated with a bond-breaking agent so that the vessel may be broken free of the grout should retrieval be necessary.", "After the grout has set, the drill string is broken with the quick disconnect.", "The drill string, grout and packer hoses are then retrieved.", "Referring to FIG. 7, a wire rope 46 from a work boat 47 is attached to a sliding thimble 48 located on the umbilical 48.", "The wire rope is used to pull the umbilical and preinstalled messenger line 49 out of the pile and lay it on the ocean floor 50.", "Referring to FIG. 8, the messenger line is pulled on deck of a work boat and attached to a marker buoy 51.", "Referring back to FIG. 1, caisson 8 is lowered along the jacket leg 9 and secured to the pile guides 10.", "A second messenger line is lowered through the caisson, passed to the work boat, and the umbilical is pulled through the caisson.", "This procedure is followed for each of the piles on the platform.", "Power and instrumentation are then connected to the umbilicals and the system is placed in operation.", "While certain specific embodiments of the invention have been described in detail, the invention is not to be limited to these embodiments, but rather by the scope of the appended claims." ]
BACKGROUND OF THE INVENTION 1. Field of Invention This invention pertains to the art of methods and apparatuses for use in lawn mowers, and more specifically to methods and apparatuses for use with a bail used with an operator present control. 2. Description of the Related Art It is well known to provide lawn mowers, such as walk-behind lawn mowers, with apparatuses and methods for detecting if the operator is properly positioned with respect to the lawn mower. Such apparatuses are often termed "operator present controls." Typically such operator present controls include a bail which is pivotably connected to the control handle of the lawn mower. The operator is required to hold the bail against the control handle thereby permitting the cutting blades of the mower to rotate. Should the operator release the bail, it is biased to pivot about the control handle thereby disengaging the cutting blades. It is known in the art to combine a bail with some type of member used to stop the pivoting of the bail when the operator has released it. For example, U.S. Pat. No. 4,805,386 discloses a bail stop that includes a clip for fastening to the bail. Similarly, U.S. Pat. No. 5,261,214 discloses a bail pivot stop that snap fits to the associated bail. All such bail stops are purportedly effective in stopping the pivoting motion of the bail. However, all such bail stops are separate pieces requiring separate manufacture and increased assembly during the manufacturing process. Thus, separate bail stops become expensive additions in the lawn mower art. The improved bail of this present invention does not require a separate bail stop. Therefore, the problems mentioned above are reduced in ways that are simple and efficient while providing better and more advantageous results. SUMMARY OF THE INVENTION According to one aspect of the present invention, there is provided a bail for use with an operator present control on an associated lawn mower. The bail includes a cross bar, first and second side bars operatively connected to the cross bar, first and second shafts operatively connected to the first and second side bars, and a pivot stop member rigidly connected to the first shaft. The pivot stop member is positioned within a hollow portion of the control handle of the lawn mower. According to another aspect of the present invention, there is provided an operator present control system for use with an associated lawn mower. The operator present control system includes disengaging means for selectively disengaging the cutting blades of the lawn mower, a bail that includes a pivot stop member that is positioned within a hollow portion of the control handle of the lawn mower, and connecting means for connecting the bail to the disengaging means. According to another aspect of the present invention, there is provided a method of stopping a bail that is used with an associated lawn mower. The method includes the steps of pivoting the bail in a first direction, contacting a pivot stop member with an inside surface of the control handle of the lawn mower, and stopping the bail. One advantage of the present invention is that a separate bail stop is not required. Another advantage of the present invention is that the pivot stop member is integrally formed of a single material along with the bail. Another advantage of the present invention is that it is easy to manufacture and can be made economically. Still other benefits and advantages of the invention will become apparent to those skilled in the art to which it pertains upon a reading and understanding of the following detailed specification. BRIEF DESCRIPTION OF THE DRAWINGS The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein: FIG. 1 is a perspective side view of a typical lawn mower that is equipped with the improved bail of the present invention. FIG. 2 is a side elevation view of the bail of this invention showing the first and second shafts. FIG. 3 is a bottom view of the bail taken along the line 3--3 of FIG. 2. FIG. 4 is a first end elevational view of the bail taken along the line 4--4 of FIG. 2 showing the angle between the pivot stop member and the first side bar. FIG. 5 is a second end elevational view of the bail taken along the line 5--5 of FIG. 2 showing the aperture in the second side bar. FIG. 6 is a sectional view taken along the line A--A of FIG. 1 showing the bail fully pivoted in a second direction, disabling the disengaging means and thereby permitting the cutting blades to rotate. FIG. 7 is a sectional view taken along the sides A--A of FIG. 1 showing the bail fully pivoted in a first direction, enabling the disengaging means and thereby preventing the cutting blades from rotating. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings wherein the showings are for purposes of illustrating a preferred embodiment of the invention only and not for purposes of limiting the same, FIG. 1 shows a lawn mower 10 which is equipped with a bail 30 in accordance with this invention. The preferred embodiment is directed to a walk-behind lawn mower but the invention is applicable to other mowers, and other applications as well. The lawn mower 10 includes a mower deck 12 which has cutting blades 13 within it. The cutting blades 13 can be of any type currently known in the art and therefore will not be discussed in any detail. An engine 14, which can be of any type chosen with sound engineering judgement, is used to rotate the cutting blades 13 in a manner commonly known in the art and therefore will not be discussed further. The engine 14 is mounted to the mower deck 12. The lawn mower 10 also includes front and back wheels 15, 16 though wheels are not required for this invention. A control handle 20 is operatively connected to the mower deck 12 by first and second legs 21, 22. Preferably the first and second legs 21, 22 are hollow. However it is only required for this invention that the first leg 21 have a first hollow portion 23 and that the second leg 22 have a second hole 26. The first hollow portion 23 has a first hole 25 for receiving the bail 30 as will be discussed further below. Similarly, it is preferred that a second hollow portion 24 in the second leg 22 has the second hole 26 for receiving the bail 30. Still referring to FIG. 1, the lawn mower 10 also includes an operator present control system 18 which is used to detect if the operator is in the correct position with respect to the lawn mower 10. In particular, the operator present control system 18 detects if the operator is holding the bail 30 against the control handle 20. The bail 30 is selectively pivotable in first direction 28 and second direction 29. The operator present control system 18 also includes disengaging means 32 for selectively disengaging the cutting blades 13 and connecting means 34 for connecting the bail 30 to the disengaging means 32. The disengaging means 32 can be of any type chosen with sound engineering judgement and currently known in the art such as engine kill switch, blade brake, blade brake clutch (BBC) and other similar devices. The connecting means 34 can also be of any type chosen with sound engineering judgement, but in this preferred embodiment is a cable 35. The operator present control system 18 preferably also includes a biasing means 36 for biasing the bail 30 in the first direction 28. In this preferred embodiment the biasing means 36 includes a spring 37 that is positioned between the cable 35 and the disengaging means 32. Thus, the spring 37 biases the bail 30 in first direction 28 by applying tension in a second direction 39 to the cable 35. The operator present control system 18 also includes the bail 30 which is operatively connected to the first and second legs 21, 22 of the control handle 20 as will be discussed further below. It should be noted that it is not necessary for the bail 30 of this invention to be used with an operator present control system. With reference now to FIGS. 1-5, the bail 30 of the preferred embodiment includes a cross bar 40 having first and second ends 41, 42. Rigidly connected to the first end 41 of the cross bar 40 is a first end 44 of a first side bar 43 that also has a second end 45. Similarly, rigidly connected to the second end 42 of the cross bar 40 is a first end 47 of a second side bar 46 that also has a second end 48. In this preferred embodiment the second side bar 46 has an aperture 49 for receiving the cable 35 by means currently known in the art. Rigidly connected to the second end 45 of the first side bar 43 is a first shaft 50. Similarly, rigidly attached to the second end 48 of the second side bar 46 is a second shaft 51. The first and second shafts 50, 51 are pivotably received inside the first and second holes 25, 26 of the first and second hollow portions 23, 24 of the first and second legs 21, 22. With reference now to FIGS. 2-5, the bail also includes a pivot stop member 54 that has first and second ends 55, 56. The first end 55 of the pivot stop 54 is rigidly connected to the first shaft 50. Though not necessary for this invention, it is preferred that the first shaft 50 and the pivot stop 54 are integrally formed of a single bar. In fact, in this preferred embodiment the bail 30 which includes the cross bar 40 the first and second side bars 43, 46, the first and second shafts 50, 51 and the pivot stop member 54 are all integrally formed of a single bar. By integrally formed of a single bar it is meant that a bar, that is preferably made of steel, is bent by means commonly known in the art, into the shape shown in FIGS. 2-5. Of course other shapes could be used for this invention. The pivot stop member 54 has a length L which will be discussed further below. The pivot stop member 54 forms an angle A with respect to the first side bar 43 that is within the range of 5° to 90°. In the preferred embodiment, the angle A is within the range of 35° to 45°. The purpose of the angle A will be discussed further below. With reference now to FIGS. 6-7, the position of the pivot stop member 54 within the first hollow portion 23 of the first leg 21 will now be discussed. The first hollow portion 23 has an inner diameter D and an inner surface 27. The length L of the pivot stop member 54 should be within the range of (0.4 times the inner diameter D) and (the internal diameter D) but is preferably within the range of (0.5 times the inner diameter D) and (0.7 times the inner diameter D). FIG. 7 shows the second end 56 of the pivot stop member 54 contacting the inner surface 27 of the first hollow portion 23 of the first leg 21 of the control handle 20. With reference now to FIGS. 1, 6-7, the operation of the bail 30 will now be discussed. FIG. 7 shows the position of the bail 30 when the lawn mower 10 is in a normal inoperative condition. Before the engine 14 can be started, the operator must pivot the bail 30 in second direction 29. This motion causes a tension force to be applied to the cable 35 in first direction 38. In this way, the operator overcomes the biasing force of the spring 37 and thereby disables the disengaging means 32. When the bail 30 is moved in second direction 29 until it reaches the position shown in FIG. 6, the operator may then start the engine 14 and thereby rotate the cutting blades 13. As long as the bail 30 remains in the position shown in FIG. 6, the operator may use the lawn mower 10 for mowing an associated lawn (not shown) in a manner commonly known in the art. Should the operator for any reason release the bail 30, the bail 30 will be forced to pivot in first direction 28 by the biasing force of the spring 37 applying a tension in the second direction 39 to the cable 35. The bail 30 will continue to pivot in first direction 28 until the second end 56 of the pivot stop member 54 contacts the inner surface 27 of the first hollow portion 23. When this occurs, the bail 30 will be prevented from pivoting any further in first direction 28. With the bail 30 positioned as shown in FIG. 7, the disengaging means 32 will be enabled and will thus prevent the cutting blades 13 from rotating preferably by stopping the engine 14. The invention has been described with reference to a preferred embodiment. Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalence thereof.
An improved bail is provided for use on a lawn mower. The bail includes a pivot stop member that is integral with the bail and which is positioned within a first hollow portion of a first leg of a control handle attached to the lawn mower. To stop the bail from pivoting in a first direction, the bail is released by the operator. A second end of a pivot stop member then comes into contact with the inside surface of the hollow portion of the first leg. This stops the bail from pivoting.
Condense the core contents of the given document.
[ "BACKGROUND OF THE INVENTION 1.", "Field of Invention This invention pertains to the art of methods and apparatuses for use in lawn mowers, and more specifically to methods and apparatuses for use with a bail used with an operator present control.", "Description of the Related Art It is well known to provide lawn mowers, such as walk-behind lawn mowers, with apparatuses and methods for detecting if the operator is properly positioned with respect to the lawn mower.", "Such apparatuses are often termed "operator present controls.", """, "Typically such operator present controls include a bail which is pivotably connected to the control handle of the lawn mower.", "The operator is required to hold the bail against the control handle thereby permitting the cutting blades of the mower to rotate.", "Should the operator release the bail, it is biased to pivot about the control handle thereby disengaging the cutting blades.", "It is known in the art to combine a bail with some type of member used to stop the pivoting of the bail when the operator has released it.", "For example, U.S. Pat. No. 4,805,386 discloses a bail stop that includes a clip for fastening to the bail.", "Similarly, U.S. Pat. No. 5,261,214 discloses a bail pivot stop that snap fits to the associated bail.", "All such bail stops are purportedly effective in stopping the pivoting motion of the bail.", "However, all such bail stops are separate pieces requiring separate manufacture and increased assembly during the manufacturing process.", "Thus, separate bail stops become expensive additions in the lawn mower art.", "The improved bail of this present invention does not require a separate bail stop.", "Therefore, the problems mentioned above are reduced in ways that are simple and efficient while providing better and more advantageous results.", "SUMMARY OF THE INVENTION According to one aspect of the present invention, there is provided a bail for use with an operator present control on an associated lawn mower.", "The bail includes a cross bar, first and second side bars operatively connected to the cross bar, first and second shafts operatively connected to the first and second side bars, and a pivot stop member rigidly connected to the first shaft.", "The pivot stop member is positioned within a hollow portion of the control handle of the lawn mower.", "According to another aspect of the present invention, there is provided an operator present control system for use with an associated lawn mower.", "The operator present control system includes disengaging means for selectively disengaging the cutting blades of the lawn mower, a bail that includes a pivot stop member that is positioned within a hollow portion of the control handle of the lawn mower, and connecting means for connecting the bail to the disengaging means.", "According to another aspect of the present invention, there is provided a method of stopping a bail that is used with an associated lawn mower.", "The method includes the steps of pivoting the bail in a first direction, contacting a pivot stop member with an inside surface of the control handle of the lawn mower, and stopping the bail.", "One advantage of the present invention is that a separate bail stop is not required.", "Another advantage of the present invention is that the pivot stop member is integrally formed of a single material along with the bail.", "Another advantage of the present invention is that it is easy to manufacture and can be made economically.", "Still other benefits and advantages of the invention will become apparent to those skilled in the art to which it pertains upon a reading and understanding of the following detailed specification.", "BRIEF DESCRIPTION OF THE DRAWINGS The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein: FIG. 1 is a perspective side view of a typical lawn mower that is equipped with the improved bail of the present invention.", "FIG. 2 is a side elevation view of the bail of this invention showing the first and second shafts.", "FIG. 3 is a bottom view of the bail taken along the line 3--3 of FIG. 2. FIG. 4 is a first end elevational view of the bail taken along the line 4--4 of FIG. 2 showing the angle between the pivot stop member and the first side bar.", "FIG. 5 is a second end elevational view of the bail taken along the line 5--5 of FIG. 2 showing the aperture in the second side bar.", "FIG. 6 is a sectional view taken along the line A--A of FIG. 1 showing the bail fully pivoted in a second direction, disabling the disengaging means and thereby permitting the cutting blades to rotate.", "FIG. 7 is a sectional view taken along the sides A--A of FIG. 1 showing the bail fully pivoted in a first direction, enabling the disengaging means and thereby preventing the cutting blades from rotating.", "DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings wherein the showings are for purposes of illustrating a preferred embodiment of the invention only and not for purposes of limiting the same, FIG. 1 shows a lawn mower 10 which is equipped with a bail 30 in accordance with this invention.", "The preferred embodiment is directed to a walk-behind lawn mower but the invention is applicable to other mowers, and other applications as well.", "The lawn mower 10 includes a mower deck 12 which has cutting blades 13 within it.", "The cutting blades 13 can be of any type currently known in the art and therefore will not be discussed in any detail.", "An engine 14, which can be of any type chosen with sound engineering judgement, is used to rotate the cutting blades 13 in a manner commonly known in the art and therefore will not be discussed further.", "The engine 14 is mounted to the mower deck 12.", "The lawn mower 10 also includes front and back wheels 15, 16 though wheels are not required for this invention.", "A control handle 20 is operatively connected to the mower deck 12 by first and second legs 21, 22.", "Preferably the first and second legs 21, 22 are hollow.", "However it is only required for this invention that the first leg 21 have a first hollow portion 23 and that the second leg 22 have a second hole 26.", "The first hollow portion 23 has a first hole 25 for receiving the bail 30 as will be discussed further below.", "Similarly, it is preferred that a second hollow portion 24 in the second leg 22 has the second hole 26 for receiving the bail 30.", "Still referring to FIG. 1, the lawn mower 10 also includes an operator present control system 18 which is used to detect if the operator is in the correct position with respect to the lawn mower 10.", "In particular, the operator present control system 18 detects if the operator is holding the bail 30 against the control handle 20.", "The bail 30 is selectively pivotable in first direction 28 and second direction 29.", "The operator present control system 18 also includes disengaging means 32 for selectively disengaging the cutting blades 13 and connecting means 34 for connecting the bail 30 to the disengaging means 32.", "The disengaging means 32 can be of any type chosen with sound engineering judgement and currently known in the art such as engine kill switch, blade brake, blade brake clutch (BBC) and other similar devices.", "The connecting means 34 can also be of any type chosen with sound engineering judgement, but in this preferred embodiment is a cable 35.", "The operator present control system 18 preferably also includes a biasing means 36 for biasing the bail 30 in the first direction 28.", "In this preferred embodiment the biasing means 36 includes a spring 37 that is positioned between the cable 35 and the disengaging means 32.", "Thus, the spring 37 biases the bail 30 in first direction 28 by applying tension in a second direction 39 to the cable 35.", "The operator present control system 18 also includes the bail 30 which is operatively connected to the first and second legs 21, 22 of the control handle 20 as will be discussed further below.", "It should be noted that it is not necessary for the bail 30 of this invention to be used with an operator present control system.", "With reference now to FIGS. 1-5, the bail 30 of the preferred embodiment includes a cross bar 40 having first and second ends 41, 42.", "Rigidly connected to the first end 41 of the cross bar 40 is a first end 44 of a first side bar 43 that also has a second end 45.", "Similarly, rigidly connected to the second end 42 of the cross bar 40 is a first end 47 of a second side bar 46 that also has a second end 48.", "In this preferred embodiment the second side bar 46 has an aperture 49 for receiving the cable 35 by means currently known in the art.", "Rigidly connected to the second end 45 of the first side bar 43 is a first shaft 50.", "Similarly, rigidly attached to the second end 48 of the second side bar 46 is a second shaft 51.", "The first and second shafts 50, 51 are pivotably received inside the first and second holes 25, 26 of the first and second hollow portions 23, 24 of the first and second legs 21, 22.", "With reference now to FIGS. 2-5, the bail also includes a pivot stop member 54 that has first and second ends 55, 56.", "The first end 55 of the pivot stop 54 is rigidly connected to the first shaft 50.", "Though not necessary for this invention, it is preferred that the first shaft 50 and the pivot stop 54 are integrally formed of a single bar.", "In fact, in this preferred embodiment the bail 30 which includes the cross bar 40 the first and second side bars 43, 46, the first and second shafts 50, 51 and the pivot stop member 54 are all integrally formed of a single bar.", "By integrally formed of a single bar it is meant that a bar, that is preferably made of steel, is bent by means commonly known in the art, into the shape shown in FIGS. 2-5.", "Of course other shapes could be used for this invention.", "The pivot stop member 54 has a length L which will be discussed further below.", "The pivot stop member 54 forms an angle A with respect to the first side bar 43 that is within the range of 5° to 90°.", "In the preferred embodiment, the angle A is within the range of 35° to 45°.", "The purpose of the angle A will be discussed further below.", "With reference now to FIGS. 6-7, the position of the pivot stop member 54 within the first hollow portion 23 of the first leg 21 will now be discussed.", "The first hollow portion 23 has an inner diameter D and an inner surface 27.", "The length L of the pivot stop member 54 should be within the range of (0.4 times the inner diameter D) and (the internal diameter D) but is preferably within the range of (0.5 times the inner diameter D) and (0.7 times the inner diameter D).", "FIG. 7 shows the second end 56 of the pivot stop member 54 contacting the inner surface 27 of the first hollow portion 23 of the first leg 21 of the control handle 20.", "With reference now to FIGS. 1, 6-7, the operation of the bail 30 will now be discussed.", "FIG. 7 shows the position of the bail 30 when the lawn mower 10 is in a normal inoperative condition.", "Before the engine 14 can be started, the operator must pivot the bail 30 in second direction 29.", "This motion causes a tension force to be applied to the cable 35 in first direction 38.", "In this way, the operator overcomes the biasing force of the spring 37 and thereby disables the disengaging means 32.", "When the bail 30 is moved in second direction 29 until it reaches the position shown in FIG. 6, the operator may then start the engine 14 and thereby rotate the cutting blades 13.", "As long as the bail 30 remains in the position shown in FIG. 6, the operator may use the lawn mower 10 for mowing an associated lawn (not shown) in a manner commonly known in the art.", "Should the operator for any reason release the bail 30, the bail 30 will be forced to pivot in first direction 28 by the biasing force of the spring 37 applying a tension in the second direction 39 to the cable 35.", "The bail 30 will continue to pivot in first direction 28 until the second end 56 of the pivot stop member 54 contacts the inner surface 27 of the first hollow portion 23.", "When this occurs, the bail 30 will be prevented from pivoting any further in first direction 28.", "With the bail 30 positioned as shown in FIG. 7, the disengaging means 32 will be enabled and will thus prevent the cutting blades 13 from rotating preferably by stopping the engine 14.", "The invention has been described with reference to a preferred embodiment.", "Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification.", "It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalence thereof." ]
RELATED PATENT APPLICATION [0001] The present invention is related to, “Compiler Apparatus and Method for Unrolling a Superblock in a Computer Program”, filed as Ser. No. 10/282,811, filed on Oct. 29, 2002, by the same inventors and owned by the current assignee at the time of the invention. The subject matter of Ser. No. 10/282,811 is hereby included by reference in its entirety. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention generally relates to computer systems, and more specifically relates to compilers that generate executable code for computer systems. [0004] 2. Description of the Related Art [0005] Since the dawn of the computer age, computer systems have evolved into extremely sophisticated devices, and computer systems may be found in many different settings. Dramatic advances in both hardware and software (e.g., computer programs) have drastically improved the performance of computer systems. Modern software has become very complex when compared to early computer programs. Many modern computer programs have tens or hundreds of thousands of instructions. The execution time (and hence, performance) of a computer program is very closely related to the number of instructions that are executed as the computer program runs. Thus, as the size and complexity of computer programs increase, the execution time of the computer program increases as well. [0006] Unlike early computer programs, modern computer programs are typically written in a high-level language that is easy to understand by a human programmer. Special software tools known as compilers take the human-readable form of a computer program, known as “source code”, and convert it into “machine code” or “object code” instructions that may be executed by a computer system. Because a compiler generates the stream of machine code instructions that are eventually executed on a computer system, the manner in which the compiler converts the source code to object code affects the execution time of the computer program. [0007] The execution time of a computer program is a function of the arrangement and type of instructions within the computer program. Loops affect the execution time of a computer program. If a computer program contains many loops, or contains any loops that are executed a relatively large number of times, the time spent executing loops will significantly impact the execution time of a computer program. [0008] In order to optimize the performance of modern computer programs, profilers have been developed to measure the run-time performance of a computer program. Profilers typically generate profile data that estimates how often different portions of the computer program are executed. Using profile data, an optimizer (such as an optimizing compiler) may make decisions to optimize loops in a computer program in order to improve the execution speed of the computer program. [0009] Known methods for using profile data to optimize loops in a computer program do not provide an optimal solution in cases where a single hot trace (that is, a single path through which execution follows for most iterations of a loop) does not extend from a beginning of a loop to an end of the loop. As a result, the prior art may yield inefficiencies in loops that result in a slower execution time for the computer program. Application Ser. No. 10/282,811 teaches a method for improving efficiencies in loops by identifying a hot trace and unrolling that hot trace; however additional improvements in loop efficiencies are needed to maximize performance of the computer system. SUMMARY OF THE INVENTION [0010] The present invention provides for loop unrolling for a class of loops that have not previously been unrolled. This class of loops comprises loops that are too large to be completely unrolled, and which lack a single hot trace that covers an entire loop iteration. [0011] In an embodiment, a method identifies loops which contain partial hot traces, using profile data. A hot trace comprises a sequence of blocks where, with high probability, control passes from each block to the next block in the sequence. A partial hot trace is a hot trace in a loop that does not cover an entire loop iteration. The method identifies a set of instructions which constitute a proper superset of the partial hot trace and a proper subset of the entire loop and which forms a complete loop iteration. This set of instructions is then unrolled (i.e., duplicated), without unrolling the entire loop. [0012] In an embodiment, an augmentation path set is identified. An augmentation path set has more than one path, or trace, through the augmentation path set, each trace in the augmentation path set having similar likelihood of being executed. A sum of the probabilities of executing each of the traces in the augmentation path set is similar to the probability of executing a particular block in the partial hot trace. Trace likelihood is determined using profile data. [0013] In an embodiment, an augmentation path set lies between a beginning of the loop and a beginning of the partial hot trace. The method augments the partial hot trace by appending the partial hot trace to the augmentation path set, forming an augmented hot trace. Unrolling of the augmented hot trace is then performed as taught for unrolling a hot trace in application Ser. No. 10/282,811. [0014] In an embodiment, an augmentation path set lies between an end of the partial hot trace and an end of the loop. The method augments the partial hot trace by appending the augmentation path set to the end of the partial hot trace, forming an augmented hot trace. Unrolling of the augmented hot trace is then performed as taught for unrolling a hot trace in application Ser. No. 10/282,811. [0015] In an embodiment, an augmentation path set lies between a first portion of the partial hot trace and a second portion of the partial hot trace. The method augments the partial hot trace by inserting the augmentation path set between the first portion of the partial hot trace and the second portion of the partial hot trace, forming an augmented hot trace. Unrolling of the augmented hot trace is then performed as taught for unrolling a hot trace in application Ser. No. 10/282,811. BRIEF DESCRIPTION OF THE DRAWINGS [0016] So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. [0017] It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. [0018] FIG. 1A shows a group of blocks in a computer program, with each transition from one block to a subsequently executed block having profiling data shown. [0019] FIG. 1B shows the group of blocks of FIG. 1A , but showing identification of a partial hot trace, an augmentation path set, and an augmented hot trace. [0020] FIG. 1C shows the augmented hot trace identified in FIG. 2 unrolled. [0021] FIG. 2A shows a group of blocks in a computer program, with each transition from one block to a subsequently executed block having profiling data shown. [0022] FIG. 2B shows the group of blocks of FIG. 2A , but showing identification of multiple partial hot traces, the partial hot traces being separated by an augmentation path set; and an augmented hot trace. [0023] FIG. 2C shows the augmented hot trace of FIG. 2B unrolled. [0024] FIG. 3 is a flow diagram describing a method of unrolling loops, including unrolling augmented hot traces. [0025] FIG. 4A shows multiple augmentation path sets and multiple partial hot traces occurring in a loop, comprising an augmented hot trace. [0026] FIG. 4B shows the augmented hot trace of FIG. 4A unrolled. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0027] The present invention provides for loop unrolling for a class of loops that have not previously been unrolled. This class of loops comprises loops that are too large to be completely unrolled, and which lack a single hot trace that covers an entire loop iteration. [0028] Turning now to FIG. 1A , a loop comprising blocks A-L is shown. Block PE is simply a loop post exit block. Profiling has been performed to determine likelihood (probabilities) of transition from one block to another, expressed as number of times the transition occurred. For example, the profiler determined that 50 transitions into the loop occurred during the period profiled. There were 250 transitions from block A to block B; 250 transitions from block A to block C. Other transition frequencies are shown next to the corresponding transition arrows. Prior compiler techniques have identified a hot trace through a loop and unrolled the trace to provide faster-running code. That is, if a sequence of blocks from a beginning of a loop to an end of a loop has a high probability of being traversed during each iteration of the loop, various trace unrolling strategies have been used. The loop shown in FIG. 1A does not have such a hot trace, since blocks B and C have similar (equal in the example of FIG. 1A ) probability of being executed. Prior trace unrolling techniques are not applicable for unrolling the loop of FIG. 1A . [0029] FIG. 1B shows the loop of FIG. 1A with a further identification of groups of blocks. A partial hot trace 10 comprising blocks D, E, and L is identified using profiling data. Blocks D, E, and L are each executed 490 times according to the profiling data. However, Blocks D, E, and L do not make up a complete path from the beginning of the loop (i.e., block A) to the end of the loop (i.e., block L), and therefore is a partial hot trace. [0030] A candidate augmentation path set 11 is identified using profiling data. A candidate augmentation path set comprises two or more blocks (A, B, and C in augmentation path set 11 in FIG. 1B ), each block having a relatively high probability of being executed during an iteration of the loop under consideration, the candidate augmentation path set being executed in series with the partial hot trace. [0031] A candidate augmentation path set has more than one path, or trace, through the candidate augmentation path set, each trace in the candidate augmentation path set having similar likelihood of being executed. A sum of the probabilities, or likelihoods, of executing each of the traces in the candidate augmentation path set is similar to (for example, within 25%) the probability of executing a particular block in the partial hot trace. For example, in partial hot trace 10 , block D is executed 500 times per the profile data. Blocks E and L in partial hot trace 10 are executed 490 times each. In the identified candidate augmentation path set 11 , block A is executed 500 times. Blocks C and D are each executed 250 times, for a total likelihood of 500. The likelihood of executing block B plus the likelihood of executing block C (total of 500) is similar to the number of executions of blocks in partial hot trace 10 (500 for block D; 490 for block E; 490 for block L). [0032] Determination of optimal unrolling methods considers advantages of reducing loop overhead, (e.g., incrementing loop counters, testing against a limit, branching) versus “code bloat”, where repetition of code during an unrolling process introduces large amounts of executable code, inclusion of which might cause needed cache lines to be disadvantageously replaced. For example, in FIG. 1B , if block B were to represent a very complex set of instructions resulting in several thousand bytes of instructions, consuming perhaps ten or more cache lines, block B (and hence candidate augmentation path set 11 ) may be rejected as an augmentation path set. [0033] Code bloat could also arise if a candidate augmentation path set comprises a large number of similarly probable traces, even if each trace is very short. For example, in an extreme case, a candidate augmentation path set could comprise 100 equally probable traces where each trace has a 1% probability of being executed. Unrolling a loop comprising such a candidate augmentation path set would result in repeating 99 unused paths in each iteration of the unroll. Such unsuitable candidate augmentation path sets are rejected as augmentation path sets. The actual number of traces having similar probabilities in a candidate augmentation path set that will be used as an augmentation path set needs to be considered based on specific characteristics of a particular computer system. In particular, cache size, cache line size, and other factors need to be considered. Advantageously, the maximum number of traces in an acceptable candidate augmentation path set is programmable, so that experimentation can be done to determine an optimum number. [0034] Although, as described above, an augmentation path set is accepted from a candidate augmentation path set in which the number of traces having similar probability is a determinant of selection, the number of traces is typically fairly small. Advantageously in many computer systems, an augmentation path set suitable for combining with a partial hot trace comprises two or three traces of similar probability, each trace being within 25% of the probability of execution of each of the other traces. Again, actual number of traces for acceptance must be determined for a particular computer system. [0035] Also advantageously, a selected augmentation path set comprises a relatively few instructions in each trace through the augmentation path set. Again, the number of instructions in each trace through the augmentation path set should be relatively small, and experimentation as to practical numbers of instructions in traces through the augmentation path set is necessary. The actual number, as above for the number of traces, depends on many factors relating to a particular computer system's design. Advantageously, in many computer systems, no more than ten, and preferably no more than five instructions are executed in any trace of an augmentation path set. [0036] In FIG. 1B , augmentation path set 11 lies between the top of partial hot trace 10 and the beginning of the loop. An augmented hot trace 12 is formed by concatenation of partial hot trace 10 and augmentation path set 11 . In another embodiment, an augmentation path set lies between the bottom of the partial hot trace and the end of the loop. In yet another embodiment, a first augmentation path set lies between the top of the partial hot trace and the beginning of the loop, and a second augmentation path set lies between the bottom of the partial hot trace and the end of the loop. [0037] FIG. 1C shows an example of unrolling of augmented hot trace set 12 without unrolling the entire loop. Blocks A 1 , B 1 , C 1 , D 1 , E 1 , and L 1 make up a first unrolled iteration of the loop; blocks A 2 , B 2 , C 2 , D 2 , E 2 , and L 2 make up a second unrolled iteration of the loop. A 1 and A 2 (and similarly, B 1 and B 2 , etc) are code instances of similarly named blocks in FIGS. 1A and 1B , without the numeric suffixes (e.g., A 1 and A 2 are instances of A). Rarely executed code (“cold traces”) is not unrolled, as doing so would tend to “bloat” the resultant code, as well as to introduce complexities that could lead to nonoptimal code, poor use of cache memory, or both. Branching to the rarely executed code (blocks F, G, H, I, J, K) is performed when needed from blocks D 1 and D 2 . A separate instantiation of block L (L′ in FIG. 1C ) is created in the set of rarely executed code to complete the loop in the example, thereby avoiding a branch back into the augmented hot trace from blocks J and K. Count rectification and other considerations of loop unrolling is performed as known by those skilled in the art, in particular, as taught in Ser. No. 10/282,811. The number of repetitions of an augmented hot trace such as augmented hot trace 12 in FIG. 1B can be any number, as will be appreciated by those skilled in the art. [0038] FIG. 2A shows another loop that can be considered for partial unrolling that has not been capable of being partially unrolled before. As with the example loop of FIG. 1A , exemplary profiling data is associated with each transition. The loop begins with block AX and ends with block HX. Block PEX is a post exit block. Block IX is seen to be rarely executed. [0039] FIG. 2B shows an identification of two partial hot traces. A first partial hot trace 20 A comprises blocks AX and BX. A second partial hot trace 20 B comprises blocks EX, GX, and HX. Blocks CX, and DX are identified as an augmentation path set 21 ; profiling data showing similar frequencies of transitions through CX and DX. As discussed before, even though augmentation path set 21 has been identified as a candidate augmentation path set, it advantageously is further examined to determine if it is suitable for being repeated in an unrolling of the loop. As before, code size (e.g., number of bytes of instructions and number of traces in a particular candidate augmentation path set) must be examined for suitability for selection of the candidate augmentation path set as an augmentation path set. The example of FIG. 2B and FIG. 2C assumes selection as an augmentation path set. [0040] FIG. 2C shows the loop of FIGS. 2A and 2B partially unrolled, with two iterations of the loop partially unrolled. Similarly named blocks (with numeric suffixes) are instances of the same block of the original loop. For example, Blocks AX 1 and AX 2 are instances of block AX. IX is a block in a “cold trace” (seldomly executed) and is not unrolled. A separate instance HX′ of the last block in the loop (i.e., HX) is placed after IX, in order to avoid branching back into the augmented hot trace. [0041] As before, to be accepted as an augmentation path set, the number of traces in a candidate augmentation path set and the number of instructions in a particular trace in a candidate augmentation path set are limited by considerations related to performance of the loop. These considerations include such system specifics as cache line size and cache size. [0042] As before, the number of iterations that are unrolled is determined by tradeoffs known in the art. Any number of iterations is contemplated. [0043] FIG. 3 shows a flowchart of an embodiment of a method to examine a program and produce partially unrolled loops, including unrolled augmented hot traces. Whereas the flowchart of FIG. 3 shows the method used once to partially unroll a loop, the method can be used for any and all instances of loops. [0044] The method begins with step 31 . [0045] In step 32 , a loop in the program's code is identified. The loop is first examined for a hot trace that extends from a beginning of the loop to an end of the loop. If such a hot trace exists, the hot trace is unrolled in step 34 . [0046] If a hot trace does not exist, control passes to step 35 , where the loop is further examined for presence of a partial hot trace. If no partial hot trace is found, no unrolling of the loop is performed, as shown in block 38 . If, however, one or more partial hot traces are found, control passes to step 36 which further examines the loop for existence of a candidate augmentation path set. Step 36 examines candidates for augmentation path sets for suitability, as described earlier (e.g., amount of code in each trace in the candidate augmentation path set and number of traces in the candidate augmentation path set). If one or more augmentation path sets are found, control passes to step 37 , which combines the one or more partial hot traces with the one or more augmentation path sets to form an augmented hot trace. Step 39 partially unrolls the augmented hot trace with “cold blocks” not being unrolled. [0047] Step 40 ends one iteration of the method. Typically, this method is used for each loop in the program under consideration. [0048] FIG. 4A illustrates the case where partial hot traces exist within a method, interspersed with augmentation path sets. The augmented hot trace 50 in FIG. 4A is composed of a series of augmented path sets (APS 1 , APS 2 , APS 3 ) and partial hot traces (PHT 1 , PHT 2 , PHT 3 ). Using profile data, cold traces such as COLD in FIG. 4A are excluded from the unrolling process resulting in a partially unrolled loop. PEY is the method exit point. [0049] FIG. 4B shows the loop of FIG. 4A partially unrolled. In FIG. 4B , each unique augmentation path set (APS) and partial hot trace (PHT) is identified by a numerical and an alphabetic suffix following the APS and PHT labels which comprise the augmented hot trace. The numerical suffix identifies each APS and PHT combination that comprises the augmented hot traces of 50 A and 50 B. The alphabetic suffix indicates how many instances of a particular hot trace have been partially unrolled—in the case of FIG. 4B , the loop in FIG. 4A has been partially unrolled twice; once instance of augmented hot trace 50 as indicated by augmented hot trace 50 A and another instance of augmented hot trace 50 , augmented hot trace 50 B. Using profile data, each of the unique augmented hot traces in the loop is advantageously unrolled while each cold trace, e.g. COLD in FIG. 4B , is not unrolled. [0050] The method described can be executed by a program product, such as a compiler. The program product contains instructions, that when executed by a suitable computer, perform the steps of the method. The program product resides on a computer readable media including but not limited to floppy disks, CD-ROMs, DVD disks, and magnetic tapes. The computer readable media can also be a network interface, such as the Worldwide Web, or any network coupling computers together over which program products may be transmitted. The present invention contemplates any media upon which a program product may be stored or over which a program product can be distributed. [0051] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
Methods and apparatus are disclosed for improved loop unrolling by a compiler. A large class of loops exists for which effective loop unrolling has not previously been performed because they are too large to be completely unrolled, but which do not have a single hot trace that covers an entire loop iteration. The present invention recognizes such loops that have partial hot traces identified using profile data. A set of instructions which constitute a proper superset of the hot trace and a proper subset of the entire loop, and which forms a complete loop iteration is identified. This set of instructions can then be unrolled without unrolling the entire loop.
Briefly describe the main idea outlined in the provided context.
[ "RELATED PATENT APPLICATION [0001] The present invention is related to, “Compiler Apparatus and Method for Unrolling a Superblock in a Computer Program”, filed as Ser.", "No. 10/282,811, filed on Oct. 29, 2002, by the same inventors and owned by the current assignee at the time of the invention.", "The subject matter of Ser.", "No. 10/282,811 is hereby included by reference in its entirety.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] The present invention generally relates to computer systems, and more specifically relates to compilers that generate executable code for computer systems.", "[0004] 2.", "Description of the Related Art [0005] Since the dawn of the computer age, computer systems have evolved into extremely sophisticated devices, and computer systems may be found in many different settings.", "Dramatic advances in both hardware and software (e.g., computer programs) have drastically improved the performance of computer systems.", "Modern software has become very complex when compared to early computer programs.", "Many modern computer programs have tens or hundreds of thousands of instructions.", "The execution time (and hence, performance) of a computer program is very closely related to the number of instructions that are executed as the computer program runs.", "Thus, as the size and complexity of computer programs increase, the execution time of the computer program increases as well.", "[0006] Unlike early computer programs, modern computer programs are typically written in a high-level language that is easy to understand by a human programmer.", "Special software tools known as compilers take the human-readable form of a computer program, known as “source code”, and convert it into “machine code”", "or “object code”", "instructions that may be executed by a computer system.", "Because a compiler generates the stream of machine code instructions that are eventually executed on a computer system, the manner in which the compiler converts the source code to object code affects the execution time of the computer program.", "[0007] The execution time of a computer program is a function of the arrangement and type of instructions within the computer program.", "Loops affect the execution time of a computer program.", "If a computer program contains many loops, or contains any loops that are executed a relatively large number of times, the time spent executing loops will significantly impact the execution time of a computer program.", "[0008] In order to optimize the performance of modern computer programs, profilers have been developed to measure the run-time performance of a computer program.", "Profilers typically generate profile data that estimates how often different portions of the computer program are executed.", "Using profile data, an optimizer (such as an optimizing compiler) may make decisions to optimize loops in a computer program in order to improve the execution speed of the computer program.", "[0009] Known methods for using profile data to optimize loops in a computer program do not provide an optimal solution in cases where a single hot trace (that is, a single path through which execution follows for most iterations of a loop) does not extend from a beginning of a loop to an end of the loop.", "As a result, the prior art may yield inefficiencies in loops that result in a slower execution time for the computer program.", "Application Ser.", "No. 10/282,811 teaches a method for improving efficiencies in loops by identifying a hot trace and unrolling that hot trace;", "however additional improvements in loop efficiencies are needed to maximize performance of the computer system.", "SUMMARY OF THE INVENTION [0010] The present invention provides for loop unrolling for a class of loops that have not previously been unrolled.", "This class of loops comprises loops that are too large to be completely unrolled, and which lack a single hot trace that covers an entire loop iteration.", "[0011] In an embodiment, a method identifies loops which contain partial hot traces, using profile data.", "A hot trace comprises a sequence of blocks where, with high probability, control passes from each block to the next block in the sequence.", "A partial hot trace is a hot trace in a loop that does not cover an entire loop iteration.", "The method identifies a set of instructions which constitute a proper superset of the partial hot trace and a proper subset of the entire loop and which forms a complete loop iteration.", "This set of instructions is then unrolled (i.e., duplicated), without unrolling the entire loop.", "[0012] In an embodiment, an augmentation path set is identified.", "An augmentation path set has more than one path, or trace, through the augmentation path set, each trace in the augmentation path set having similar likelihood of being executed.", "A sum of the probabilities of executing each of the traces in the augmentation path set is similar to the probability of executing a particular block in the partial hot trace.", "Trace likelihood is determined using profile data.", "[0013] In an embodiment, an augmentation path set lies between a beginning of the loop and a beginning of the partial hot trace.", "The method augments the partial hot trace by appending the partial hot trace to the augmentation path set, forming an augmented hot trace.", "Unrolling of the augmented hot trace is then performed as taught for unrolling a hot trace in application Ser.", "No. 10/282,811.", "[0014] In an embodiment, an augmentation path set lies between an end of the partial hot trace and an end of the loop.", "The method augments the partial hot trace by appending the augmentation path set to the end of the partial hot trace, forming an augmented hot trace.", "Unrolling of the augmented hot trace is then performed as taught for unrolling a hot trace in application Ser.", "No. 10/282,811.", "[0015] In an embodiment, an augmentation path set lies between a first portion of the partial hot trace and a second portion of the partial hot trace.", "The method augments the partial hot trace by inserting the augmentation path set between the first portion of the partial hot trace and the second portion of the partial hot trace, forming an augmented hot trace.", "Unrolling of the augmented hot trace is then performed as taught for unrolling a hot trace in application Ser.", "No. 10/282,811.", "BRIEF DESCRIPTION OF THE DRAWINGS [0016] So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.", "[0017] It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.", "[0018] FIG. 1A shows a group of blocks in a computer program, with each transition from one block to a subsequently executed block having profiling data shown.", "[0019] FIG. 1B shows the group of blocks of FIG. 1A , but showing identification of a partial hot trace, an augmentation path set, and an augmented hot trace.", "[0020] FIG. 1C shows the augmented hot trace identified in FIG. 2 unrolled.", "[0021] FIG. 2A shows a group of blocks in a computer program, with each transition from one block to a subsequently executed block having profiling data shown.", "[0022] FIG. 2B shows the group of blocks of FIG. 2A , but showing identification of multiple partial hot traces, the partial hot traces being separated by an augmentation path set;", "and an augmented hot trace.", "[0023] FIG. 2C shows the augmented hot trace of FIG. 2B unrolled.", "[0024] FIG. 3 is a flow diagram describing a method of unrolling loops, including unrolling augmented hot traces.", "[0025] FIG. 4A shows multiple augmentation path sets and multiple partial hot traces occurring in a loop, comprising an augmented hot trace.", "[0026] FIG. 4B shows the augmented hot trace of FIG. 4A unrolled.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0027] The present invention provides for loop unrolling for a class of loops that have not previously been unrolled.", "This class of loops comprises loops that are too large to be completely unrolled, and which lack a single hot trace that covers an entire loop iteration.", "[0028] Turning now to FIG. 1A , a loop comprising blocks A-L is shown.", "Block PE is simply a loop post exit block.", "Profiling has been performed to determine likelihood (probabilities) of transition from one block to another, expressed as number of times the transition occurred.", "For example, the profiler determined that 50 transitions into the loop occurred during the period profiled.", "There were 250 transitions from block A to block B;", "250 transitions from block A to block C. Other transition frequencies are shown next to the corresponding transition arrows.", "Prior compiler techniques have identified a hot trace through a loop and unrolled the trace to provide faster-running code.", "That is, if a sequence of blocks from a beginning of a loop to an end of a loop has a high probability of being traversed during each iteration of the loop, various trace unrolling strategies have been used.", "The loop shown in FIG. 1A does not have such a hot trace, since blocks B and C have similar (equal in the example of FIG. 1A ) probability of being executed.", "Prior trace unrolling techniques are not applicable for unrolling the loop of FIG. 1A .", "[0029] FIG. 1B shows the loop of FIG. 1A with a further identification of groups of blocks.", "A partial hot trace 10 comprising blocks D, E, and L is identified using profiling data.", "Blocks D, E, and L are each executed 490 times according to the profiling data.", "However, Blocks D, E, and L do not make up a complete path from the beginning of the loop (i.e., block A) to the end of the loop (i.e., block L), and therefore is a partial hot trace.", "[0030] A candidate augmentation path set 11 is identified using profiling data.", "A candidate augmentation path set comprises two or more blocks (A, B, and C in augmentation path set 11 in FIG. 1B ), each block having a relatively high probability of being executed during an iteration of the loop under consideration, the candidate augmentation path set being executed in series with the partial hot trace.", "[0031] A candidate augmentation path set has more than one path, or trace, through the candidate augmentation path set, each trace in the candidate augmentation path set having similar likelihood of being executed.", "A sum of the probabilities, or likelihoods, of executing each of the traces in the candidate augmentation path set is similar to (for example, within 25%) the probability of executing a particular block in the partial hot trace.", "For example, in partial hot trace 10 , block D is executed 500 times per the profile data.", "Blocks E and L in partial hot trace 10 are executed 490 times each.", "In the identified candidate augmentation path set 11 , block A is executed 500 times.", "Blocks C and D are each executed 250 times, for a total likelihood of 500.", "The likelihood of executing block B plus the likelihood of executing block C (total of 500) is similar to the number of executions of blocks in partial hot trace 10 (500 for block D;", "490 for block E;", "490 for block L).", "[0032] Determination of optimal unrolling methods considers advantages of reducing loop overhead, (e.g., incrementing loop counters, testing against a limit, branching) versus “code bloat”, where repetition of code during an unrolling process introduces large amounts of executable code, inclusion of which might cause needed cache lines to be disadvantageously replaced.", "For example, in FIG. 1B , if block B were to represent a very complex set of instructions resulting in several thousand bytes of instructions, consuming perhaps ten or more cache lines, block B (and hence candidate augmentation path set 11 ) may be rejected as an augmentation path set.", "[0033] Code bloat could also arise if a candidate augmentation path set comprises a large number of similarly probable traces, even if each trace is very short.", "For example, in an extreme case, a candidate augmentation path set could comprise 100 equally probable traces where each trace has a 1% probability of being executed.", "Unrolling a loop comprising such a candidate augmentation path set would result in repeating 99 unused paths in each iteration of the unroll.", "Such unsuitable candidate augmentation path sets are rejected as augmentation path sets.", "The actual number of traces having similar probabilities in a candidate augmentation path set that will be used as an augmentation path set needs to be considered based on specific characteristics of a particular computer system.", "In particular, cache size, cache line size, and other factors need to be considered.", "Advantageously, the maximum number of traces in an acceptable candidate augmentation path set is programmable, so that experimentation can be done to determine an optimum number.", "[0034] Although, as described above, an augmentation path set is accepted from a candidate augmentation path set in which the number of traces having similar probability is a determinant of selection, the number of traces is typically fairly small.", "Advantageously in many computer systems, an augmentation path set suitable for combining with a partial hot trace comprises two or three traces of similar probability, each trace being within 25% of the probability of execution of each of the other traces.", "Again, actual number of traces for acceptance must be determined for a particular computer system.", "[0035] Also advantageously, a selected augmentation path set comprises a relatively few instructions in each trace through the augmentation path set.", "Again, the number of instructions in each trace through the augmentation path set should be relatively small, and experimentation as to practical numbers of instructions in traces through the augmentation path set is necessary.", "The actual number, as above for the number of traces, depends on many factors relating to a particular computer system's design.", "Advantageously, in many computer systems, no more than ten, and preferably no more than five instructions are executed in any trace of an augmentation path set.", "[0036] In FIG. 1B , augmentation path set 11 lies between the top of partial hot trace 10 and the beginning of the loop.", "An augmented hot trace 12 is formed by concatenation of partial hot trace 10 and augmentation path set 11 .", "In another embodiment, an augmentation path set lies between the bottom of the partial hot trace and the end of the loop.", "In yet another embodiment, a first augmentation path set lies between the top of the partial hot trace and the beginning of the loop, and a second augmentation path set lies between the bottom of the partial hot trace and the end of the loop.", "[0037] FIG. 1C shows an example of unrolling of augmented hot trace set 12 without unrolling the entire loop.", "Blocks A 1 , B 1 , C 1 , D 1 , E 1 , and L 1 make up a first unrolled iteration of the loop;", "blocks A 2 , B 2 , C 2 , D 2 , E 2 , and L 2 make up a second unrolled iteration of the loop.", "A 1 and A 2 (and similarly, B 1 and B 2 , etc) are code instances of similarly named blocks in FIGS. 1A and 1B , without the numeric suffixes (e.g., A 1 and A 2 are instances of A).", "Rarely executed code (“cold traces”) is not unrolled, as doing so would tend to “bloat”", "the resultant code, as well as to introduce complexities that could lead to nonoptimal code, poor use of cache memory, or both.", "Branching to the rarely executed code (blocks F, G, H, I, J, K) is performed when needed from blocks D 1 and D 2 .", "A separate instantiation of block L (L′ in FIG. 1C ) is created in the set of rarely executed code to complete the loop in the example, thereby avoiding a branch back into the augmented hot trace from blocks J and K. Count rectification and other considerations of loop unrolling is performed as known by those skilled in the art, in particular, as taught in Ser.", "No. 10/282,811.", "The number of repetitions of an augmented hot trace such as augmented hot trace 12 in FIG. 1B can be any number, as will be appreciated by those skilled in the art.", "[0038] FIG. 2A shows another loop that can be considered for partial unrolling that has not been capable of being partially unrolled before.", "As with the example loop of FIG. 1A , exemplary profiling data is associated with each transition.", "The loop begins with block AX and ends with block HX.", "Block PEX is a post exit block.", "Block IX is seen to be rarely executed.", "[0039] FIG. 2B shows an identification of two partial hot traces.", "A first partial hot trace 20 A comprises blocks AX and BX.", "A second partial hot trace 20 B comprises blocks EX, GX, and HX.", "Blocks CX, and DX are identified as an augmentation path set 21 ;", "profiling data showing similar frequencies of transitions through CX and DX.", "As discussed before, even though augmentation path set 21 has been identified as a candidate augmentation path set, it advantageously is further examined to determine if it is suitable for being repeated in an unrolling of the loop.", "As before, code size (e.g., number of bytes of instructions and number of traces in a particular candidate augmentation path set) must be examined for suitability for selection of the candidate augmentation path set as an augmentation path set.", "The example of FIG. 2B and FIG. 2C assumes selection as an augmentation path set.", "[0040] FIG. 2C shows the loop of FIGS. 2A and 2B partially unrolled, with two iterations of the loop partially unrolled.", "Similarly named blocks (with numeric suffixes) are instances of the same block of the original loop.", "For example, Blocks AX 1 and AX 2 are instances of block AX.", "IX is a block in a “cold trace”", "(seldomly executed) and is not unrolled.", "A separate instance HX′ of the last block in the loop (i.e., HX) is placed after IX, in order to avoid branching back into the augmented hot trace.", "[0041] As before, to be accepted as an augmentation path set, the number of traces in a candidate augmentation path set and the number of instructions in a particular trace in a candidate augmentation path set are limited by considerations related to performance of the loop.", "These considerations include such system specifics as cache line size and cache size.", "[0042] As before, the number of iterations that are unrolled is determined by tradeoffs known in the art.", "Any number of iterations is contemplated.", "[0043] FIG. 3 shows a flowchart of an embodiment of a method to examine a program and produce partially unrolled loops, including unrolled augmented hot traces.", "Whereas the flowchart of FIG. 3 shows the method used once to partially unroll a loop, the method can be used for any and all instances of loops.", "[0044] The method begins with step 31 .", "[0045] In step 32 , a loop in the program's code is identified.", "The loop is first examined for a hot trace that extends from a beginning of the loop to an end of the loop.", "If such a hot trace exists, the hot trace is unrolled in step 34 .", "[0046] If a hot trace does not exist, control passes to step 35 , where the loop is further examined for presence of a partial hot trace.", "If no partial hot trace is found, no unrolling of the loop is performed, as shown in block 38 .", "If, however, one or more partial hot traces are found, control passes to step 36 which further examines the loop for existence of a candidate augmentation path set.", "Step 36 examines candidates for augmentation path sets for suitability, as described earlier (e.g., amount of code in each trace in the candidate augmentation path set and number of traces in the candidate augmentation path set).", "If one or more augmentation path sets are found, control passes to step 37 , which combines the one or more partial hot traces with the one or more augmentation path sets to form an augmented hot trace.", "Step 39 partially unrolls the augmented hot trace with “cold blocks”", "not being unrolled.", "[0047] Step 40 ends one iteration of the method.", "Typically, this method is used for each loop in the program under consideration.", "[0048] FIG. 4A illustrates the case where partial hot traces exist within a method, interspersed with augmentation path sets.", "The augmented hot trace 50 in FIG. 4A is composed of a series of augmented path sets (APS 1 , APS 2 , APS 3 ) and partial hot traces (PHT 1 , PHT 2 , PHT 3 ).", "Using profile data, cold traces such as COLD in FIG. 4A are excluded from the unrolling process resulting in a partially unrolled loop.", "PEY is the method exit point.", "[0049] FIG. 4B shows the loop of FIG. 4A partially unrolled.", "In FIG. 4B , each unique augmentation path set (APS) and partial hot trace (PHT) is identified by a numerical and an alphabetic suffix following the APS and PHT labels which comprise the augmented hot trace.", "The numerical suffix identifies each APS and PHT combination that comprises the augmented hot traces of 50 A and 50 B. The alphabetic suffix indicates how many instances of a particular hot trace have been partially unrolled—in the case of FIG. 4B , the loop in FIG. 4A has been partially unrolled twice;", "once instance of augmented hot trace 50 as indicated by augmented hot trace 50 A and another instance of augmented hot trace 50 , augmented hot trace 50 B. Using profile data, each of the unique augmented hot traces in the loop is advantageously unrolled while each cold trace, e.g. COLD in FIG. 4B , is not unrolled.", "[0050] The method described can be executed by a program product, such as a compiler.", "The program product contains instructions, that when executed by a suitable computer, perform the steps of the method.", "The program product resides on a computer readable media including but not limited to floppy disks, CD-ROMs, DVD disks, and magnetic tapes.", "The computer readable media can also be a network interface, such as the Worldwide Web, or any network coupling computers together over which program products may be transmitted.", "The present invention contemplates any media upon which a program product may be stored or over which a program product can be distributed.", "[0051] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow." ]
This application claims priority to U.S. provisional application No. 60/491,255, filed Jul. 31, 2003, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a method of diagnosing tuberculosis by culturing lymphocytes from a subject to produce antibodies, and measuring the concentration of antibodies reactive with a tuberculosis antigen. 2. Background Information Tuberculosis (TB) remains a major global health problem and is the most frequent cause of death from a single infectious agent [1]. The appearance of multidrug-resistant strains of Mycobacterium tuberculosis and the HIV/AIDS epidemic have contributed to the resurgence of active TB in humans. Thus, WHO declared tuberculosis a global emergency in 1993. Surveys carried out in Bangladesh from 1987 to the present suggest the smear positive TB case rate in Bangladesh to be between 1-1.8% [2-5]. Early diagnosis of TB is crucial to prevent the spread of the disease in the community. However, the clinical and laboratory diagnosis, follow-up of the infection activity and response to the therapy is not always easy to evaluate [6, 7]. Although, culture of bacteria is the gold standard in diagnosis and follow-up of disease, it can take up to 6-8 weeks to isolate M. tuberculosis . It is estimated that a false negative culture result may be obtained in 10-20% of TB cases [8, 9]. A rapid serological test for diagnosis, follow-up of disease activity and response to therapy would be very useful to the clinicians [10, 11]. The PPD skin test (Mantoux test) is an important tool for diagnosis of latent TB infection and disease in the developed world but it has low predictive value in Bacillus-Calmette-Guerin (BCG)-vaccinated individuals as well as in individuals living in areas endemic for TB due to cross-reactivity with BCG and atypical mycobacteria, and false negative reactions in malnourished children [12-14]. BCG has been used as an antigen in enzyme immunoassays in in vitro studies to determine the disease activity but was aborted due to difficulties in interpretation, or differentiating between active or past disease, and low sensitivity and specificity, respectively [15-19]. With the identification of regions of M. tuberculosis genome that are missing in BCG and nontuberculous mycobacterium, new antigens have been identified providing better opportunities for development of novel diagnostic tools [20-22]. The introduction of these antigens resulted in a much higher sensitivity and specificity in cell response assays [23]. However, serological tests based on mycobacterial antigens to detect circulating antibodies have been hampered by decreased sensitivity and cross-reactivity with other mycobacteria [24-28] or have relatively limited utility in the diagnosis of tuberculosis in countries where tuberculosis is endemic [29]. Several molecular biological techniques have been proposed as indicators of disease activity in pulmonary and extrapulmonary tuberculosis [30, 31] and are currently the most sensitive and specific diagnostic tests. However, a recent study on inter-laboratory comparisons of PCR-based TB diagnosis have demonstrated the complications of obtaining reproducible results with such sensitive techniques where false positive results can be a major problem [32]. The diagnosis of tuberculosis is currently made using one of several methods: 1) a positive culture for tuberculosis from a sputum or other biological sample, 2) a positive smear of sputum in which typical tuberculosis organisms are seen microscopically, 3) a positive histological examination of tissue from the patient, 4) a positive skin test (PPD) in a patient with a clinical examination suggestive of tuberculosis. These methods suffer from a number of drawbacks. First, culture methods are time consuming, generally taking several weeks to perform. In addition, if the amount of sample being tested is insufficient, they result in substantial numbers of false negatives. The sputum smear suffers from poor sensitivity. The histological examination requires an invasive procedure and is generally only performed in the case of extrapulmonary tuberculosis. The skin test results in many false positive and false negative reactions; furthermore, a positive result does not distinguish between active disease, inactive infection, prior immunization with BCG vaccine, or exposure to similar organism(s). Although a number of blood tests have been explored in attempts to overcome these problems, all have suffered from a lack of sensitivity and specificity. Thus, there is a need for a test that will more rapidly detect tuberculosis infection, and that will distinguish active disease from inactive disease, BCG vaccination, and exposure to similar organisms. In vitro assay of antibody secretion by lymphocytes (“ALS assay”) has been previously used to measure postvaccination immunity following cholera vaccination [33] but has not been used for the detection of active infection, in particular active tuberculosis infection. In the present invention we demonstrate the diagnostic potential of tuberculosis-specific ALS responses in Bangladeshi subjects for the assessment of active pulmonary tuberculosis and detection of infection in exposed symptom-free contacts of TB index cases. SUMMARY OF THE INVENTION The present invention provides a method for the detection of active infection with tuberculosis and other infectious diseases that makes use of antibodies produced in vitro by lymphocytes from peripheral blood. This method can also be used for identifying subclinical TB infection in asymptomatic contacts of TB index cases that later progress to active TB. The method uses a sample of blood of a patient suspected of having a specific infectious disease (e.g. tuberculosis). Lymphocytes from the patient sample are separated from other blood cells and are cultured under suitable conditions, following which the concentration of antibodies specific for the infectious disease present in the culture medium are measured. Culture of the lymphocytes can be carried out for a suitable time period to obtain a measurable concentration of antibodies specific for the suspected disease, compared to a baseline (“0”) value measured in normal control subjects. In the case of tuberculosis, a period of 1-5 days, preferably 3 days, has been found to be suitable. A skilled practitioner will be able to determine other suitable time-periods for tuberculosis and other diseases using routine experimentation. Antibody concentrations can be determined by measuring the amount of antibody bound to an antigen specific for the microorganism causing a particular disease using methods that are known in the art, for example, Enzyme-linked Immunosorbent Assay (ELISA). In an alternative embodiment of the invention, other known methods of detecting antibody production in circulating lymphocytes, or counting the numbers of antibody secreting cells, can be used. For example, the cells may be enumerated using methods such as Enzyme-linked Immunospot (ELISPOT) or may be labeled using fluorescent labeled antibody and counted using a Fluorescence Activating Cell Sorter. To measure the number of antibody producing cells using fluorescent labeled antibody, it is assumed that the antibody for the disease of interest (e.g. an antituberculosis antibody) is located on the surface of the lymphocyte. After separation from the other cells (as in the ALS assay), the lymphocytes are mixed and incubated with antigen (e.g. BCG, PPD, early secretory antigenic target-6 (ESAT-6), lipoarabinomannan (LAM), culture-filtrate protein (CFP) or other suitable tuberculosis antigen for a suitable period (e.g one hour). The cells are then washed to remove any unbound antigen, and mixed and incubated with a fluorescent labeled antibody to the disease of interest (e.g. a labeled antituberculosis antibody). This labeled antibody will only bind to the cells that have already bound the tuberculosis antigen. The concentration of these cells can then be determined by counting the fluorescent cells using a fluorescent activated cell sorter or a fluorescent microscope. In the case of tuberculosis BCG, PPD, ESAT-6, LAM, CFP and other crude or purified antigens that are representative of tuberculosis bacteria can be used. The amount of antibody secreted by the lymphocytes of the test subject (or the number of actively secreting lymphocytes) is compared to the amount secreted by a normal (control) subject, who is known to be uninfected. Antibody production may also be compared with that of subjects who have received BCG vaccine. An increase in the titer of antibody in the patients above that of the control subjects is indicative of active tuberculosis infection. The amount of the increase above that of the controls is determined by statistical analysis such that the titers of groups of subjects with infection is statistically higher than the titers of groups of control subjects. Suitable standard curves can be run to establish antibody levels that are indicative of active infection for other diseases and antigens, using control subjects and subjects that are known to be actively infected. Culture conditions for lymphocytes are familiar to those skilled in the art and are described in the attached manuscript. Typical steps in the lymphocyte culture methods include separating the lymphocytes from the other cells in the blood, adjusting the cell concentrations to a standard number of cells per milliliter, and culturing them in a suitable tissue culture medium in an incubator at about 37° C. with a 5% CO 2 atmosphere. Other diseases for which the method should be particularly suitable are other chronic infections such as chronic fungal infections (e.g. coccidiomycosis, histoplasmosis) chronic bacterial infections (e.g. Helicobactor pylori ), chronic parasitic infection (e.g. visceral leishmaniasis). These infections, like tuberculosis, may also result in inactive infections and active infections, and the test is expected to help distinguish active from inactive infection. Accordingly, in one embodiment, the invention provides a method of diagnosing tuberculosis in a subject comprising culturing lymphocytes from said subject under suitable conditions such that antibodies are produced, and measuring the concentration of antibodies reactive with a tuberculosis antigen, wherein an increase in said concentration over a normal control sample is indicative of active tuberculosis infection. Control samples representing known positive and negative samples, can be included for quality control purposes. From a baseline value determined for the control samples, a cutoff point for the diagnosis of infection will generally be selected that represents a value that has been predetermined by testing control and patient populations or which is in the best judgment of the practitioner the level of antibody at which a positive diagnosis can be made, e.g. 10% above control, 20% above control, etc., depending on the patient population and the experience of the practitioner. Preferably, the lymphocytes are cultured for 1-5 days, more preferably for 2-4 days. In one preferred embodiment, the lymphocytes are separated from other blood cells prior to culture. The tuberculosis antigen used for this aspect of the invention may be any antigen that is specific for tuberculosis and that is capable of eliciting antibody production from lymphocytes under suitable culture conditions. Preferably, the antigen is selected from the group consisting of BCG, PPD, ESAT-6, LAM and CFP. The invention also includes a method of diagnosing tuberculosis in a subject comprising i) obtaining a blood sample from said subject; ii) separating lymphocytes from the sample; iii) culturing the lymphocytes in a culture medium under suitable conditions; iv) measuring the concentration of antibodies reactive with a tuberculosis antigen in said medium; wherein an increase in said concentration over a normal control sample is indicative of active tuberculosis infection. Preferably, the antigen is selected from the group consisting of BCG, PPD, ESAT-6, LAM and CFP. The assay also enables detection of infection in exposed, symptom-free contacts, which are at greater risk of developing active TB. The potential applications of the ALS assay would include evaluation of recent TB contacts in countries with high TB rates and in industrialized countries for contact tracing as well as for screening of immigrants from TB endemic countries. In particularly preferred embodiments of the methods of the invention, antibodies are detected using ELISA or an immunochromatographic method. The concentration of antibody-producing lymphocytes in the peripheral blood may be measured using ELISPOT or by tagging the lymphocytes with a detectable marker, such as a radioisotopically labeled or fluorescent labeled antibody. The invention also includes a method of diagnosing active infection in a subject comprising culturing lymphocytes from said subject under suitable conditions such that antibodies are produced and measuring the concentration of antibodies reactive with a target disease antigen, wherein an increase in said concentration over a normal control sample is indicative of active infection with the target disease. In one preferred embodiment of this aspect of the invention, the target disease is a chronic infection, such as, for example, tuberculosis, coccidiomycosis, histoplasmosis, Helicobactor pylori , or visceral leishmaniasis. The lymphocytes are cultured for a suitable time period necessary for antibody production, generally 1-5 days, more preferably 2-4 days. Preferably, the lymphocytes are separated from other blood cells prior to culture. The invention also includes a method of diagnosing active infection of a target disease in a subject, said method comprising measuring the number of lymphocytes present in a blood sample obtained from said subject that secret antibodies reactive with a specific target disease antigen, wherein an increase in said number over a normal control sample is indicative of active infection with the target disease. In one preferred embodiment of this aspect of the invention, the target disease is a chronic infection, for example, tuberculosis, coccidiomycosis, or histoplasmosis, Helicobactor pylori , or visceral leishmaniasis. The invention also includes a kit for carrying out the methods of the invention, the kit comprising a suitable antigen specific for the disease to be detected, and optionally reagents needed for culturing lymphocytes and detecting any resulting antibodies. The kit might also include reagents for carrying out suitable baseline and/or control samples. Assuming that the laboratory to be conducting the test would have basic laboratory supplies and equipment such as a CO 2 incubator, centrifuge, ELISA reader, plastics, etc, the kit for the detection of tuberculosis might include, for example: 1. A tube for collecting a blood sample and reagents/supplies for separating lymphocytes (mononuclear cells), or a Vacutainer™ CPT™ tube (Becton Dickinson) single tube system for collection of whole blood and separation of mononuclear cells 2. Tube(s) or plate for culturing the lymphocytes 3. Tissue culture media for maintaining the lymphocytes in culture for up to 5 days. 4. A vial for holding the tissue culture media after the lymphocytes have been incubated, (e.g. microfuge tubes or cryovials) 5. A microtiter plate coated with TB antigen for carrying out the ELISA reaction 6. control reagents which known to give positive and negative reactions as quality control standards 7. Enzyme labeled antibody for the ELISA test 8. Substrate for the ELISA test 9. Buffers for the ELISA test Although the inventors do not intend to be bound by any particular theory, it is believed that active infection results in constant stimulation of antibody-producing cells and that this stimulation results in constant circulation of antibody-producing cells in the peripheral blood. In contrast, old inactive infection or prior vaccination may result in high antibody serum titers, but not in constant stimulation, thus there will be few antibody-producing cells circulating in the peripheral blood. References cited herein are hereby incorporated by reference. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 . Comparison of BCG-specific IgG responses (relative titers) in lymphocyte secretions at various cell concentrations in patients and healthy controls. Each point represents average titers of BCG-specific IgG with standard error of mean (±SE). Significantly higher BCG-specific IgG titers were obtained at higher cell concentrations (2-10×10 6 cells/mL) compared to 1×10 6 cells/mL (P<0.001). Healthy controls had consistently low BCG-specific IgG titers at all cell concentrations. FIG. 2 . Comparison of BCG-specific IgG responses (relative titers) in lymphocyte secretions at various incubation time intervals in patients and healthy controls. The horizontal bars represent geometric mean titers of specific IgG. TB patients (▴) had significantly high specific IgG titers at all time points compared to healthy controls (●) (P<0.001). Healthy controls had consistently low BCG-specific IgG titers at all incubation time points. FIGS. 3A and 3B . The ALS responses to BCG ( FIG. 3A ) and PPD ( FIG. 3B ) in patients with tuberculosis (●) were significantly higher than in non-tuberculosis patients (▪) and healthy controls (▴, ▾) (P<0.001). Statistical comparison between groups were performed using the ANOVA or ANOVA on ranks. Short horizontal lines represent geometric mean titers for the groups. FIGS. 4A and 4B . Receiver-operator characteristic (ROC) curves were constructed from ALS responses to BCG ( FIG. 4A ) and PPD ( FIG. 4B ) in 49 tuberculosis patients and in 35 healthy controls. Some potential cutoff levels are indicated by arrows. DETAILED DESCRIPTION OF THE INVENTION Materials and Methods Study Subjects and Sampling. Adult patients with suspected pulmonary tuberculosis from the National Institute of Diseases of the Chest and Hospital (NIDCH) in Dhaka, Bangladesh were prospectively studied. The diagnosis of tuberculosis was established by the clinical presentation, chest X-ray examination and sputum smear positivity. Clinical evaluation included lung opacity, pyrexia, weight loss, high erythrocyte sedimentation rate (ESR) and positive sputum smear. Sputum was collected twice on consecutive days for mycobacterial culture from each patient after enrollment. Diagnosis was further confirmed when sputum culture was found to be positive. All patients received standard therapy that included rifampicin, isoniazid, pyrazinamide and ethambutol. Most of these patients had been ill for 3-5 months prior to inclusion in the study. Tuberculin skin test was not performed in these patients since in Bangladesh BCG is given to about 80% of people, exposure to environmental mycobacteria is considered to be widespread and incidence of tuberculosis infection is high rendering the skin test less specific [5, 34, 35). The history and inspection for typical scar included detecting a scar resulting from previous vaccination with M. bovis BCG. Although it is also possible that some patients may not develop a scar after vaccination and may be falsely grouped as non-vaccinated, most of these patients were however able to tell whether they were vaccinated or not with the exception of two who were unsure of their vaccination status and did not have the scars. They were grouped as non-vaccinated. Patients attending the hospital with symptoms suggestive of tuberculosis with lung opacity, high ESR but sputum smear negative and culture negative were enrolled as non-tuberculosis patients. Healthy laboratory personnel (with no known exposure to M. tuberculosis ) were also selected as healthy controls. Tuberculin skin test was performed on these healthy controls only. Blood was collected from each patient at enrollment with <4 weeks of antimycobacterial drug treatment. In addition, blood was also collected from the non-tuberculosis patients and healthy subjects. The study was approved by the ethical review committee of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B): International Center for Health and Population Research in Dhaka. Signed informed consent was obtained from each study subject according to the guidelines of the ethical review committee. Sputum Culture Sputum from patients were collected at the NIDCH and were cultured for M. tuberculosis at the ICDDR,B on Lowenstein Jensen medium using standard culture techniques. Antibodies from Lymphocyte Secretions (ALS). Peripheral blood mononuclear cells (PBMC) were separated from blood upon Ficoll-Paque by differential centrifugation, and were suspended in 24-well tissue culture plates (Costar, Cambridge, Mass.) in RPMI 1640 culture medium (GIBCO BRL, Grand Island, N.Y.) containing 10% fetal bovine serum (GIBCO), 2 mM L-glutamine and 1% amphotericin B-penicillin-streptomycin-mix (Sigma Chemicals Co., St; Louis, Mo.). Different dilutions of PBMC (1×10 6 , 2×10 6 , 5×10 6 and 1×10 7 cells/ml) were incubated at 37° C. with 5% CO 2 . Culture supernatants were collected at 24, 48, 72 and 96 hours post incubation. A cocktail of protease inhibitors (4-aminoethyl benzenesulfonyl flouride, 0.2 μg/ml; Aprotinin, 1 μg/ml; Leupeptin 10 μm; sodium azide 1 mg/ml in PBS) were added to the supernatants and were stored at −70° C. until used for the assay. Antigen-Specific IgG Antibodies in Lymphocyte Secretions. Antigens tested for the method were BCG (Freeze-dried, glutamate-BCG vaccine for intradermal use, lot # 1861, Japan BCG Laboratories, Japan; no preservatives added, saline used as diluent), and purified protein derivative (PPD, Sigma Chemical Co, St Louis, Mo.). Antibody (IgG) titers were measured in supernatants by the enzyme-linked immunosorbant assay (ELISA). Polystyrene microtitre plates (Nunc-Maxisorp) were first coated with BCG vaccine (1 μg/well) or PPD (1 μg/well) in carbonate buffer (0.1 M sodium bicarbonate and 5 mM magnesium chloride, pH-9.8) and incubated overnight at 4° C. After washing, the plates were blocked with 10% FBS in phosphate buffered saline (PBS, pH 7.2) and incubated at 37° C. for 60 minutes. Lymphocyte supernatants were thawed and brought to room temperature. Following washing with PBS-tween, lymphocyte supernatants of appropriate dilutions (diluted in 10% FBS in PBS) were added (100 μL/well) and incubated for 2 hours at 37° C. Plates were washed and rabbit anti human IgG HRP conjugate (1:100) in PBS containing 10% FBS was added and incubated for 2 hours at room temperature. After washing, freshly prepared substrate (O-phenylenediamine (OPD; 1 mg/ml in 0.1M sodium citrate (pH-4.5) buffer and H 2 O 2 ) was added and the plates were developed. The enzyme reaction was stopped with 1.0 M H 2 SO 4 and optical density (OD) was measured after 20 min at 492 nm. Pooled sera from M. tuberculosis culture positive patients were used as positive control (OD>1.0). Antigen-specific responses were expressed as relative titers, which were defined as the optical density multiplied by the dilution factor of the specimen [36]. Statistical Analysis Statistical analyses were carried out using the SigmaStat software (Jandel Scientific, San Rafael, Calif.). Comparisons between the groups were made using the One Way Analysis of Variance (ANOVA) or ANOVA on ranks as appropriate. P-values were considered significant when ≦0.05. Receiver-operator characteristic (ROC) curves were constructed to describe the relation between the sensitivity and specificity at varying cutoff levels of BCG- or PPD-specific IgG titers in lymphocyte secretions (ALS). Results Demography of Patients Forty-nine patients with suspected pulmonary TB were recruited from Institute of Diseases of the Chest and Hospital (IDCH). Only those patients who had two consecutive-sputum specimens positive for acid-fast bacilli (AFB) were included in the study. Out of 49 patients with smear positive pulmonary TB, 45 patients were culture positive for M. tuberculosis (92%) and 2 had contaminated culture and 2 were culture negative. All patients received the standard treatment and for therapy-resistant cases, the treatment was modified. Median age of the patients was 30 years with a range of 18 to 57 years. Thirty-six of forty-nine TB patients were males and thirteen were females. Among them, thirty-five were BCG vaccinated (having a BCG scar). Patients with non-tuberculosis illness (n=35) included patients with bronchiectasis (n=22), lung cancer (n=7), lung abscess (n=4) and aspergillosis (n=2). The diagnosis was confirmed by histology or cytology. Thirty-five healthy individuals (laboratory personnel) were included in the study as healthy controls all of whom except one were BCG vaccinated. Lymphocyte Numbers and Supernatant Dilution. Culture supernatants from different concentrations of cell suspensions and different incubation time points were used to determine antigen-specific IgG titers. With higher concentration of PBMC, higher BCG-specific IgG titers were obtained ( FIG. 1 ). BCG-specific IgG titers were significantly higher in supernatants of 2, 5 and 10 million cells compared to that in 1 million cells (P<0.001). For 2 to 10×10 6 PBMC/ml, the supernatants need to be diluted 2-4 times. However with the cell concentration of 1×10 6 PBMC/ml, undiluted supernatants had to be used. Since the PBMC counts are usually low in moderate to severely sick TB patients, we opted for one million cell/ml suspensions. BCG- and PPD-Specific Antibodies in Lymphocyte Secretions A gradual increase in relative titers of BCG-specific antibody was found from 48 to 72 hours with a slight decline in the titers at 96 hours ( FIG. 2 ). The titers at 24 h were low and only studied in a few subjects. The optimum time point was found to be 72 hours. Pulmonary TB patients had significantly higher BCG-specific IgG antibody titers than healthy subjects (P<0.001), and non-TB patients (P<0.001) at all time points ( FIG. 3A ). Response to PPD ( FIG. 3B ) was similar to that seen with BCG-vaccine. There was no significant difference in the BCG-specific antibody titers between patients with (35 vaccinated; geometric mean (GM) of relative titer-0.67) or without BCG vaccination (14 non-vaccinated; GM=0.75) (P=0.5). Cutoff Level to Define a Positive Test Result ROC curves were constructed from the ALS responses to BCG or PPD comparing TB patients with healthy controls. The selection of the best cutoff point value was based on the level at which the accuracy was maximum. The best cutoff point was found to be 0.42 with a sensitivity of 92.5% and a specificity of 80% for the BCG-ALS assay ( FIG. 4A ). For PPD-specific response, the best cut-off value was 0.32 with a sensitivity of 73% and a specificity of 80% for the ALS assay ( Fig. 4B ). The sensitivity and specificity for BCG-ALS assay were higher than those ofPPD-specific ALS assay. The positive predictive value of the assay was 97%. Discussion A rapid diagnostic assay that can detect patients with active tuberculosis is urgently needed to control and prevent the spread of pulmonary tuberculosis. We report a novel technique to rapidly identify such patients by culturing peripheral blood lymphocytes and detection of tuberculosis-specific antibodies in lymphocyte secretions. Comparison between bacteriologically confirmed TB patients and non-tuberculosis patients (having illness in which TB was part of the differential diagnosis) or healthy controls showed a significant difference in the BCG antigen-specific-IgG antibody responses in the secretions. The sensitivity and specificity of the test were about 93% and 80% respectively indicating that the combination of the ALS and ELISA assays using BCG vaccine as an antigen would enable rapid detection of M tuberculosis infection (within 4-5 days) in patients with active tuberculosis. Prior BCG vaccination did not hamper the test for identification of TB and could successfully differentiate between BCG-vaccinated and M. tuberculosis infected patients. The positive predictive value of the test was 97%. Detection of antigen specific antibody secreting cells (ASC) have been used for monitoring therapeutic responses in TB patients [37]. We evaluated the ALS technique because we hypothesized that active tuberculosis would provide continuous antigen stimulation resulting in antibody producing cells in circulation. By contrast inactive tuberculosis might result in high antibody titers in serum but would be less likely to stimulate antibody producing cells in circulation. In addition, it is easier to perform ALS assay and the supernatant can also be stored for future use to detect antigen-specific antibodies, novel antigens, cytokines and other mediators. BCG-vaccine and PPD were chosen as antigens for the easy availability and assessment of a broad spectrum of TB-specific antibodies, since they cover a vast array of protein and lipid antigens. ALS response to both BCG and PPD were similar however, the sensitivity and specificity of the BCG-specific ALS response were higher. Our ongoing follow-up study of family contacts indicates that increased ALS responses to BCG or PPD are associated with increased risk of developing active TB. Various purified protein antigens have been tested for diagnostic applications; for example, ESAT-6, which is a small molecular weight peptide expressed by M. tuberculosis, M. bovis and M. africanum and is absent from all strains of M. bovis and most of the environmental mycobacteria. Recent studies have found ESAT-6 to be a highly promising antigen for immunodiagnosis of active M. tuberculosis infection in nonendemic regions [38-41]. However, in regions endemic for tuberculosis such as The Gambia, India and Bangladesh, contacts of TB patients had significantly higher ESAT-6 specific response than TB patients [29, 42] thereby limiting the use of the method to nonendemic countries. There is a long term persistence of ESAT-6 specific antibodies in patients in remission from pulmonary TB in endemic areas making it difficult to discriminate between latent TB or remission from TB [43]. In conclusion, the use of the ALS specimens with the standard ELISA technique holds potential as a future TB-specific diagnostic test. With the extensive availability of ELISA technology in developing country settings, this method should be applicable both in developing countries endemic for TB as well as industrialized countries for screening of suspected patients. Since this method does not require specimen from the site of disease, it should also be useful in diagnosis of paucibacillary childhood TB. References cited herein are listed below for convenience. 1. WHO report 1999. Global Tuberculosis Control: Communicable Diseases, WHO. Geneva: World Health Organization, 1999. 2. Director General (DG) Health Services: Report on the national prevalence survey on tuberculosis in Bangladesh, 1987-88. Dhaka: Dhaka: Ministry of Health and Family Welfare. 1989. 3. Kumaresan J A R M, Murray C J L. Tuberculosis. In: Murray C L J L A, ed. Global Health Statistics—global burden of disease and injury series. Vol. 2. Boston, Mass.: Harvard University press, 1996:142-7. 4. Global Tuberculosis Control: Surveillance, Planning, Financing. In: Organization WH, ed. WHO Report 2002: Geneva, Switzerland, 2002. 5. Surveillance for multidrug resistant Mycobacterium tuberculosis. 2001-2002. ICDDR,B: Health and Science Bulletin. Vol. 1, 2002:6-10. 6. Ameglio F, Giannarelli D, Cordiali-Fei P, et al. Use of discriminant analysis to assess disease activity in pulmonary tuberculosis with a panel of specific and nonspecific serum markers. Am J Clin Pathol 1994;101:719-25. 7. Saltini C, Colizzi V. Soluble immunological markers of disease activity in tuberculosis. Eur Respir J 1999;14:485-6. 8. Kothadia S N, Deshmukh S and Saoji A M. Evaluation of direct microscopy as a screening test in the diagnosis of pulmonary tuberculosis. Indian J Pathol Microbiol 1990;33:68-73. 9. Pottumarthy S M A, Harrison A C, Wells V C. Evaluation of the tuberculin gamma interferon assay: potential to replace the Montoux skin test. J CLin Microbiol 1999;37(10):3229-32. 10. al-Hajjaj M S, Gad-el-Rab M O, al-Orainey I O and al-Kassimi F A. Improved sensitivity for detection of tuberculosis cases by a modified Anda-TB ELISA test. Tuber Lung Dis 1999;79:181-5. 11. Yilmaz A, Ece F, Bayramgurler B, Akkaya E and Baran R. The value of Ca 125 in the evaluation of tuberculosis activity. Respir Med 2001;95:666-9. 12. Huebner R E S M, Bass J B. The tuberculin skin test. Clin Infect Dis 1993;17:968-75. 13. Donald P R. Childhood tuberculosis. Curr Opin Pulm Med 2000;6:187-92. 14. Fine P E, Sterne J A, Ponnighaus J M and Rees R J. Delayed-type hypersensitivity, mycobacterial vaccines and protective immunity. Lancet 1994;344: 1245-9. 15. Dhand R, Ganguly N K, Vaishnavi C, Gilhotra R and Malik S K. False-positive reactions with enzyme-linked immunosorbent assay of Mycobacterium tuberculosis antigens in pleural fluid. J Med Microbiol 1988;26:241-3. 16. Wang C R, Liu M F, Chen M Y, Lin T P, Cheng C S and Chuang C Y. Enzyme-linked immunosorbent assay with BCG sonicate antigen for diagnostic potential of mycobacterial infection in Taiwan. Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi 1989;22:97-104. 17. Aoki A, Hagiwara E, Shirai A, et al. [Their titers and recognized molecules of IgG class anti-BCG antibody in sera from patients with tuberculosis]. Nihon Kyobu Shikkan Gakkai Zasshi 1990;28:729-35. 18. Banchuin N, Wongwajana S, Pumprueg U and Jearanaisilavong J. Value of an ELISA for mycobacterial antigen detection as a routine diagnostic test of pulmonary tuberculosis. Asian Pac J Allergy Immunol 1990;8:5-11. 19. Lu C Z, Qiao J, Shen T and Link H. Early diagnosis of tuberculous meningitis by detection of anti-BCG secreting cells in cerebrospinal fluid. Lancet 1990;336:10-3. 20. Arend S M A P, Meijgaarden K E V, Skojot R L V, Subronto Y W, Dissel J T V, Ottenhoff T H M. Detection of active tuberculosis infection by T cell responses to early-secreted antigenic target 6-kDa protein and culture filtrate protein 10. J Infect Dis 2000; 181:1850-4. 21. Doherty M L, Cassidy J P. New perspectives on bovine tuberculosis. Vet J 2002;163:109-10. 22. Pollock J M, Andersen P. The potential of the ESAT-6 antigen secreted by virulent mycobacteria for specific diagnosis of tuberculosis. J Infect Dis 1997;175:1251-4. 23. van Pinxteren L A H R P, Affer E M, Pollock J, Andersen P. Diagnosis of tuberculosis based on the two specific antigens ESAT-6 and CFP10. Clin Diagnos Lab Immunol 2000;7:155-60. 24. Querol J M, Oltra C, Granda D, et al. [Usefulness of IgG and IgM detection against antigen 60 in the diagnosis of thoracic tuberculosis]. An Med Intema 1993; 10:271-4. 25. Qadri S M, Smith K K. Nonspecificity of the Anda A60-tb ELISA test for serodiagnosis of mycobacterial disease. Can J Microbiol 1992;38:804-6. 26. Maes R F. Evaluation of the avidity of IgG anti-mycobacterial antibodies in tuberculous patients serum by an A-60 immunoassay. Eur J Epidemiol 1991;7:188-90. 27. Delacourt C, Gobin J, Gaillard J L, de Blic J, Veron M and Scheinmann P. Value of ELISA using antigen 60 for the diagnosis of tuberculosis in children. Chest 1993;104:393-8. 28. Turneer M, Van Nerom E, Nyabenda J, Waelbroeck A, Duvivier A and Toppet M. Determination of humoral immunoglobulins M and G directed against mycobacterial antigen 60 failed to diagnose primary tuberculosis and mycobacterial adenitis in children. Am.J Respir Crit Care Med 1994;150:1508-12. 29. Vekemans J, Lienhardt C, Sillah J S, et al. Tuberculosis contacts but not patients have higher gamma interferon responses to ESAT-6 than do community controls in The Gambia. Infect Immun 2001;69:6554-7. 30. Lyashchenko K, Colangeli R, Houde M, Al-Jahdali H, Menzies D and Gennaro M L. Heterogeneous antibody responses in tuberculosis. Infect Immun 1998;66:3936-40. 31. Daniel T. Immunodiagnosis of tuberculosis. In: S G, ed. Tuberculosis. Boston: Little Brown and Company, 1996:223-33 32. Noordhoek G T, Arend H J K, Bjune G, et al. Sensitivity and specificity of PCR for detection of Mycobacterium tuberculosis : a blind comparison study among seven laboratories. J Clin. Microb. 1994;32:277-84. 33. Chang H S, Sack D A. Development of a novel in vitro assay (ALS assay) for evaluation of vaccine-induced antibody secretion from circulating mucosal lymphocytes. Clin Diagn Lab Immunol 2001;8:482-8. 34. Organization W H. Global tuberculosis control, 1999. WHO/CDS/TB/2000.275. Geneva, Switzerland.: World Health Organization, 2000 35. Fine P. Variation in protection by BCG: implications of end for heterologous immunity. Lancet 1995;346:1339-45. 36. Islam D W B, Ryd M, Lindberg A A, Christensson B. Immunoglobulin subclass distribution and dynamics of Shigella -specific antibody responses in serum and stool samples in shigellosis. Infect Immun 1995;63:2054-61. 37. Sousa A O W A, Poinsignon Y, Simonney N, Gerber F, Lavergne F, Herrmann J L, Lagrange P H. Kinetics of circulating antibodies, immune complex and specific antibody-secreting cells in tuberculosis patients during 6 months of antimicrobial therapy. Tubercle Lung Dis 2000;80(1):27-33. 38. Andersen P, Munk M E, Pollock J M and Doherty T M. Specific immune-based diagnosis of tuberculosis. Lancet 2000;356:1099-104. 39. Johnson P D, Stuart R L, Grayson M L, et al. Tuberculin-purified protein derivative-, MPT-64- and ESAT-6-stimulated gamma interferon responses in medical students before and after Mycobacterium bovis BCG vaccination and in patients with tuberculosis. Clin Diagn Lab Immunol 1999;6:934-7. 40. Lein A D, von Reyn C F, Ravn P, Horsburgh C R, Jr., Alexander L N and Andersen P. Cellular immune responses to ESAT-6 discriminate between patients with pulmonary disease due to Mycobacterium avium complex and those with pulmonary disease due to Mycobacterium tuberculosis . Clin Diagn Lab Immunol 1999;6:606-9. 41. Ravn P, Demissie A, Eguale T, et al. Human T cell responses to the ESAT-6 antigen from Mycobacterium tuberculosis . J Infect Dis 1999;179:637-45. 42. Lalvani A, Nagvenkar P, Udwadia Z, et al. Enumeration of T cells specific for RD1-encoded antigens suggests a high prevalence of latent Mycobacterium tuberculosis infection in healthy urban Indians. J Infect Dis 2001;183:469-77. 43. Wu-Hsieh B A, Chen C-K, Chang J-H, et al. Long-lived immune response to early secretory antigenic target 6 in individuals who had recovered from tuberculosis. Clin Infect Dis 2001;33:1336-40. 44. Azim T, Islam M N, Bogaerts J, et al. Prevalence of HIV and syphilis among high-risk groups in Bangladesh. Aids 2000;14:210-1. 45. Azim T, Bogaerts J, Yirrell D L, et al. Injecting drug users in Bangladesh: prevalence of syphilis, hepatitis, HIV and HIV subtypes. Aids 2002;16:121-3.
A method and kit for the detection of an infectious disease, particularly tuberculosis, wherein lymphocytes of a subject are incubated with a disease-specific antigen, and the level of antibody production is measured, the production of antibodies above a baseline level being indicative of infection.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "This application claims priority to U.S. provisional application No. 60/491,255, filed Jul. 31, 2003, the entire contents of which are incorporated herein by reference.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The invention relates to a method of diagnosing tuberculosis by culturing lymphocytes from a subject to produce antibodies, and measuring the concentration of antibodies reactive with a tuberculosis antigen.", "Background Information Tuberculosis (TB) remains a major global health problem and is the most frequent cause of death from a single infectious agent [1].", "The appearance of multidrug-resistant strains of Mycobacterium tuberculosis and the HIV/AIDS epidemic have contributed to the resurgence of active TB in humans.", "Thus, WHO declared tuberculosis a global emergency in 1993.", "Surveys carried out in Bangladesh from 1987 to the present suggest the smear positive TB case rate in Bangladesh to be between 1-1.8% [2-5].", "Early diagnosis of TB is crucial to prevent the spread of the disease in the community.", "However, the clinical and laboratory diagnosis, follow-up of the infection activity and response to the therapy is not always easy to evaluate [6, 7].", "Although, culture of bacteria is the gold standard in diagnosis and follow-up of disease, it can take up to 6-8 weeks to isolate M. tuberculosis .", "It is estimated that a false negative culture result may be obtained in 10-20% of TB cases [8, 9].", "A rapid serological test for diagnosis, follow-up of disease activity and response to therapy would be very useful to the clinicians [10, 11].", "The PPD skin test (Mantoux test) is an important tool for diagnosis of latent TB infection and disease in the developed world but it has low predictive value in Bacillus-Calmette-Guerin (BCG)-vaccinated individuals as well as in individuals living in areas endemic for TB due to cross-reactivity with BCG and atypical mycobacteria, and false negative reactions in malnourished children [12-14].", "BCG has been used as an antigen in enzyme immunoassays in in vitro studies to determine the disease activity but was aborted due to difficulties in interpretation, or differentiating between active or past disease, and low sensitivity and specificity, respectively [15-19].", "With the identification of regions of M. tuberculosis genome that are missing in BCG and nontuberculous mycobacterium, new antigens have been identified providing better opportunities for development of novel diagnostic tools [20-22].", "The introduction of these antigens resulted in a much higher sensitivity and specificity in cell response assays [23].", "However, serological tests based on mycobacterial antigens to detect circulating antibodies have been hampered by decreased sensitivity and cross-reactivity with other mycobacteria [24-28] or have relatively limited utility in the diagnosis of tuberculosis in countries where tuberculosis is endemic [29].", "Several molecular biological techniques have been proposed as indicators of disease activity in pulmonary and extrapulmonary tuberculosis [30, 31] and are currently the most sensitive and specific diagnostic tests.", "However, a recent study on inter-laboratory comparisons of PCR-based TB diagnosis have demonstrated the complications of obtaining reproducible results with such sensitive techniques where false positive results can be a major problem [32].", "The diagnosis of tuberculosis is currently made using one of several methods: 1) a positive culture for tuberculosis from a sputum or other biological sample, 2) a positive smear of sputum in which typical tuberculosis organisms are seen microscopically, 3) a positive histological examination of tissue from the patient, 4) a positive skin test (PPD) in a patient with a clinical examination suggestive of tuberculosis.", "These methods suffer from a number of drawbacks.", "First, culture methods are time consuming, generally taking several weeks to perform.", "In addition, if the amount of sample being tested is insufficient, they result in substantial numbers of false negatives.", "The sputum smear suffers from poor sensitivity.", "The histological examination requires an invasive procedure and is generally only performed in the case of extrapulmonary tuberculosis.", "The skin test results in many false positive and false negative reactions;", "furthermore, a positive result does not distinguish between active disease, inactive infection, prior immunization with BCG vaccine, or exposure to similar organism(s).", "Although a number of blood tests have been explored in attempts to overcome these problems, all have suffered from a lack of sensitivity and specificity.", "Thus, there is a need for a test that will more rapidly detect tuberculosis infection, and that will distinguish active disease from inactive disease, BCG vaccination, and exposure to similar organisms.", "In vitro assay of antibody secretion by lymphocytes (“ALS assay”) has been previously used to measure postvaccination immunity following cholera vaccination [33] but has not been used for the detection of active infection, in particular active tuberculosis infection.", "In the present invention we demonstrate the diagnostic potential of tuberculosis-specific ALS responses in Bangladeshi subjects for the assessment of active pulmonary tuberculosis and detection of infection in exposed symptom-free contacts of TB index cases.", "SUMMARY OF THE INVENTION The present invention provides a method for the detection of active infection with tuberculosis and other infectious diseases that makes use of antibodies produced in vitro by lymphocytes from peripheral blood.", "This method can also be used for identifying subclinical TB infection in asymptomatic contacts of TB index cases that later progress to active TB.", "The method uses a sample of blood of a patient suspected of having a specific infectious disease (e.g. tuberculosis).", "Lymphocytes from the patient sample are separated from other blood cells and are cultured under suitable conditions, following which the concentration of antibodies specific for the infectious disease present in the culture medium are measured.", "Culture of the lymphocytes can be carried out for a suitable time period to obtain a measurable concentration of antibodies specific for the suspected disease, compared to a baseline (“0”) value measured in normal control subjects.", "In the case of tuberculosis, a period of 1-5 days, preferably 3 days, has been found to be suitable.", "A skilled practitioner will be able to determine other suitable time-periods for tuberculosis and other diseases using routine experimentation.", "Antibody concentrations can be determined by measuring the amount of antibody bound to an antigen specific for the microorganism causing a particular disease using methods that are known in the art, for example, Enzyme-linked Immunosorbent Assay (ELISA).", "In an alternative embodiment of the invention, other known methods of detecting antibody production in circulating lymphocytes, or counting the numbers of antibody secreting cells, can be used.", "For example, the cells may be enumerated using methods such as Enzyme-linked Immunospot (ELISPOT) or may be labeled using fluorescent labeled antibody and counted using a Fluorescence Activating Cell Sorter.", "To measure the number of antibody producing cells using fluorescent labeled antibody, it is assumed that the antibody for the disease of interest (e.g. an antituberculosis antibody) is located on the surface of the lymphocyte.", "After separation from the other cells (as in the ALS assay), the lymphocytes are mixed and incubated with antigen (e.g. BCG, PPD, early secretory antigenic target-6 (ESAT-6), lipoarabinomannan (LAM), culture-filtrate protein (CFP) or other suitable tuberculosis antigen for a suitable period (e.", "g one hour).", "The cells are then washed to remove any unbound antigen, and mixed and incubated with a fluorescent labeled antibody to the disease of interest (e.g. a labeled antituberculosis antibody).", "This labeled antibody will only bind to the cells that have already bound the tuberculosis antigen.", "The concentration of these cells can then be determined by counting the fluorescent cells using a fluorescent activated cell sorter or a fluorescent microscope.", "In the case of tuberculosis BCG, PPD, ESAT-6, LAM, CFP and other crude or purified antigens that are representative of tuberculosis bacteria can be used.", "The amount of antibody secreted by the lymphocytes of the test subject (or the number of actively secreting lymphocytes) is compared to the amount secreted by a normal (control) subject, who is known to be uninfected.", "Antibody production may also be compared with that of subjects who have received BCG vaccine.", "An increase in the titer of antibody in the patients above that of the control subjects is indicative of active tuberculosis infection.", "The amount of the increase above that of the controls is determined by statistical analysis such that the titers of groups of subjects with infection is statistically higher than the titers of groups of control subjects.", "Suitable standard curves can be run to establish antibody levels that are indicative of active infection for other diseases and antigens, using control subjects and subjects that are known to be actively infected.", "Culture conditions for lymphocytes are familiar to those skilled in the art and are described in the attached manuscript.", "Typical steps in the lymphocyte culture methods include separating the lymphocytes from the other cells in the blood, adjusting the cell concentrations to a standard number of cells per milliliter, and culturing them in a suitable tissue culture medium in an incubator at about 37° C. with a 5% CO 2 atmosphere.", "Other diseases for which the method should be particularly suitable are other chronic infections such as chronic fungal infections (e.g. coccidiomycosis, histoplasmosis) chronic bacterial infections (e.g. Helicobactor pylori ), chronic parasitic infection (e.g. visceral leishmaniasis).", "These infections, like tuberculosis, may also result in inactive infections and active infections, and the test is expected to help distinguish active from inactive infection.", "Accordingly, in one embodiment, the invention provides a method of diagnosing tuberculosis in a subject comprising culturing lymphocytes from said subject under suitable conditions such that antibodies are produced, and measuring the concentration of antibodies reactive with a tuberculosis antigen, wherein an increase in said concentration over a normal control sample is indicative of active tuberculosis infection.", "Control samples representing known positive and negative samples, can be included for quality control purposes.", "From a baseline value determined for the control samples, a cutoff point for the diagnosis of infection will generally be selected that represents a value that has been predetermined by testing control and patient populations or which is in the best judgment of the practitioner the level of antibody at which a positive diagnosis can be made, e.g. 10% above control, 20% above control, etc.", ", depending on the patient population and the experience of the practitioner.", "Preferably, the lymphocytes are cultured for 1-5 days, more preferably for 2-4 days.", "In one preferred embodiment, the lymphocytes are separated from other blood cells prior to culture.", "The tuberculosis antigen used for this aspect of the invention may be any antigen that is specific for tuberculosis and that is capable of eliciting antibody production from lymphocytes under suitable culture conditions.", "Preferably, the antigen is selected from the group consisting of BCG, PPD, ESAT-6, LAM and CFP.", "The invention also includes a method of diagnosing tuberculosis in a subject comprising i) obtaining a blood sample from said subject;", "ii) separating lymphocytes from the sample;", "iii) culturing the lymphocytes in a culture medium under suitable conditions;", "iv) measuring the concentration of antibodies reactive with a tuberculosis antigen in said medium;", "wherein an increase in said concentration over a normal control sample is indicative of active tuberculosis infection.", "Preferably, the antigen is selected from the group consisting of BCG, PPD, ESAT-6, LAM and CFP.", "The assay also enables detection of infection in exposed, symptom-free contacts, which are at greater risk of developing active TB.", "The potential applications of the ALS assay would include evaluation of recent TB contacts in countries with high TB rates and in industrialized countries for contact tracing as well as for screening of immigrants from TB endemic countries.", "In particularly preferred embodiments of the methods of the invention, antibodies are detected using ELISA or an immunochromatographic method.", "The concentration of antibody-producing lymphocytes in the peripheral blood may be measured using ELISPOT or by tagging the lymphocytes with a detectable marker, such as a radioisotopically labeled or fluorescent labeled antibody.", "The invention also includes a method of diagnosing active infection in a subject comprising culturing lymphocytes from said subject under suitable conditions such that antibodies are produced and measuring the concentration of antibodies reactive with a target disease antigen, wherein an increase in said concentration over a normal control sample is indicative of active infection with the target disease.", "In one preferred embodiment of this aspect of the invention, the target disease is a chronic infection, such as, for example, tuberculosis, coccidiomycosis, histoplasmosis, Helicobactor pylori , or visceral leishmaniasis.", "The lymphocytes are cultured for a suitable time period necessary for antibody production, generally 1-5 days, more preferably 2-4 days.", "Preferably, the lymphocytes are separated from other blood cells prior to culture.", "The invention also includes a method of diagnosing active infection of a target disease in a subject, said method comprising measuring the number of lymphocytes present in a blood sample obtained from said subject that secret antibodies reactive with a specific target disease antigen, wherein an increase in said number over a normal control sample is indicative of active infection with the target disease.", "In one preferred embodiment of this aspect of the invention, the target disease is a chronic infection, for example, tuberculosis, coccidiomycosis, or histoplasmosis, Helicobactor pylori , or visceral leishmaniasis.", "The invention also includes a kit for carrying out the methods of the invention, the kit comprising a suitable antigen specific for the disease to be detected, and optionally reagents needed for culturing lymphocytes and detecting any resulting antibodies.", "The kit might also include reagents for carrying out suitable baseline and/or control samples.", "Assuming that the laboratory to be conducting the test would have basic laboratory supplies and equipment such as a CO 2 incubator, centrifuge, ELISA reader, plastics, etc, the kit for the detection of tuberculosis might include, for example: 1.", "A tube for collecting a blood sample and reagents/supplies for separating lymphocytes (mononuclear cells), or a Vacutainer™ CPT™ tube (Becton Dickinson) single tube system for collection of whole blood and separation of mononuclear cells 2.", "Tube(s) or plate for culturing the lymphocytes 3.", "Tissue culture media for maintaining the lymphocytes in culture for up to 5 days.", "A vial for holding the tissue culture media after the lymphocytes have been incubated, (e.g. microfuge tubes or cryovials) 5.", "A microtiter plate coated with TB antigen for carrying out the ELISA reaction 6.", "control reagents which known to give positive and negative reactions as quality control standards 7.", "Enzyme labeled antibody for the ELISA test 8.", "Substrate for the ELISA test 9.", "Buffers for the ELISA test Although the inventors do not intend to be bound by any particular theory, it is believed that active infection results in constant stimulation of antibody-producing cells and that this stimulation results in constant circulation of antibody-producing cells in the peripheral blood.", "In contrast, old inactive infection or prior vaccination may result in high antibody serum titers, but not in constant stimulation, thus there will be few antibody-producing cells circulating in the peripheral blood.", "References cited herein are hereby incorporated by reference.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 .", "Comparison of BCG-specific IgG responses (relative titers) in lymphocyte secretions at various cell concentrations in patients and healthy controls.", "Each point represents average titers of BCG-specific IgG with standard error of mean (±SE).", "Significantly higher BCG-specific IgG titers were obtained at higher cell concentrations (2-10×10 6 cells/mL) compared to 1×10 6 cells/mL (P<0.001).", "Healthy controls had consistently low BCG-specific IgG titers at all cell concentrations.", "FIG. 2 .", "Comparison of BCG-specific IgG responses (relative titers) in lymphocyte secretions at various incubation time intervals in patients and healthy controls.", "The horizontal bars represent geometric mean titers of specific IgG.", "TB patients (▴) had significantly high specific IgG titers at all time points compared to healthy controls (●) (P<0.001).", "Healthy controls had consistently low BCG-specific IgG titers at all incubation time points.", "FIGS. 3A and 3B .", "The ALS responses to BCG ( FIG. 3A ) and PPD ( FIG. 3B ) in patients with tuberculosis (●) were significantly higher than in non-tuberculosis patients (▪) and healthy controls (▴, ▾) (P<0.001).", "Statistical comparison between groups were performed using the ANOVA or ANOVA on ranks.", "Short horizontal lines represent geometric mean titers for the groups.", "FIGS. 4A and 4B .", "Receiver-operator characteristic (ROC) curves were constructed from ALS responses to BCG ( FIG. 4A ) and PPD ( FIG. 4B ) in 49 tuberculosis patients and in 35 healthy controls.", "Some potential cutoff levels are indicated by arrows.", "DETAILED DESCRIPTION OF THE INVENTION Materials and Methods Study Subjects and Sampling.", "Adult patients with suspected pulmonary tuberculosis from the National Institute of Diseases of the Chest and Hospital (NIDCH) in Dhaka, Bangladesh were prospectively studied.", "The diagnosis of tuberculosis was established by the clinical presentation, chest X-ray examination and sputum smear positivity.", "Clinical evaluation included lung opacity, pyrexia, weight loss, high erythrocyte sedimentation rate (ESR) and positive sputum smear.", "Sputum was collected twice on consecutive days for mycobacterial culture from each patient after enrollment.", "Diagnosis was further confirmed when sputum culture was found to be positive.", "All patients received standard therapy that included rifampicin, isoniazid, pyrazinamide and ethambutol.", "Most of these patients had been ill for 3-5 months prior to inclusion in the study.", "Tuberculin skin test was not performed in these patients since in Bangladesh BCG is given to about 80% of people, exposure to environmental mycobacteria is considered to be widespread and incidence of tuberculosis infection is high rendering the skin test less specific [5, 34, 35).", "The history and inspection for typical scar included detecting a scar resulting from previous vaccination with M. bovis BCG.", "Although it is also possible that some patients may not develop a scar after vaccination and may be falsely grouped as non-vaccinated, most of these patients were however able to tell whether they were vaccinated or not with the exception of two who were unsure of their vaccination status and did not have the scars.", "They were grouped as non-vaccinated.", "Patients attending the hospital with symptoms suggestive of tuberculosis with lung opacity, high ESR but sputum smear negative and culture negative were enrolled as non-tuberculosis patients.", "Healthy laboratory personnel (with no known exposure to M. tuberculosis ) were also selected as healthy controls.", "Tuberculin skin test was performed on these healthy controls only.", "Blood was collected from each patient at enrollment with <4 weeks of antimycobacterial drug treatment.", "In addition, blood was also collected from the non-tuberculosis patients and healthy subjects.", "The study was approved by the ethical review committee of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B): International Center for Health and Population Research in Dhaka.", "Signed informed consent was obtained from each study subject according to the guidelines of the ethical review committee.", "Sputum Culture Sputum from patients were collected at the NIDCH and were cultured for M. tuberculosis at the ICDDR,B on Lowenstein Jensen medium using standard culture techniques.", "Antibodies from Lymphocyte Secretions (ALS).", "Peripheral blood mononuclear cells (PBMC) were separated from blood upon Ficoll-Paque by differential centrifugation, and were suspended in 24-well tissue culture plates (Costar, Cambridge, Mass.) in RPMI 1640 culture medium (GIBCO BRL, Grand Island, N.Y.) containing 10% fetal bovine serum (GIBCO), 2 mM L-glutamine and 1% amphotericin B-penicillin-streptomycin-mix (Sigma Chemicals Co., St;", "Louis, Mo.).", "Different dilutions of PBMC (1×10 6 , 2×10 6 , 5×10 6 and 1×10 7 cells/ml) were incubated at 37° C. with 5% CO 2 .", "Culture supernatants were collected at 24, 48, 72 and 96 hours post incubation.", "A cocktail of protease inhibitors (4-aminoethyl benzenesulfonyl flouride, 0.2 μg/ml;", "Aprotinin, 1 μg/ml;", "Leupeptin 10 μm;", "sodium azide 1 mg/ml in PBS) were added to the supernatants and were stored at −70° C. until used for the assay.", "Antigen-Specific IgG Antibodies in Lymphocyte Secretions.", "Antigens tested for the method were BCG (Freeze-dried, glutamate-BCG vaccine for intradermal use, lot # 1861, Japan BCG Laboratories, Japan;", "no preservatives added, saline used as diluent), and purified protein derivative (PPD, Sigma Chemical Co, St Louis, Mo.).", "Antibody (IgG) titers were measured in supernatants by the enzyme-linked immunosorbant assay (ELISA).", "Polystyrene microtitre plates (Nunc-Maxisorp) were first coated with BCG vaccine (1 μg/well) or PPD (1 μg/well) in carbonate buffer (0.1 M sodium bicarbonate and 5 mM magnesium chloride, pH-9.8) and incubated overnight at 4° C. After washing, the plates were blocked with 10% FBS in phosphate buffered saline (PBS, pH 7.2) and incubated at 37° C. for 60 minutes.", "Lymphocyte supernatants were thawed and brought to room temperature.", "Following washing with PBS-tween, lymphocyte supernatants of appropriate dilutions (diluted in 10% FBS in PBS) were added (100 μL/well) and incubated for 2 hours at 37° C. Plates were washed and rabbit anti human IgG HRP conjugate (1:100) in PBS containing 10% FBS was added and incubated for 2 hours at room temperature.", "After washing, freshly prepared substrate (O-phenylenediamine (OPD;", "1 mg/ml in 0.1M sodium citrate (pH-4.5) buffer and H 2 O 2 ) was added and the plates were developed.", "The enzyme reaction was stopped with 1.0 M H 2 SO 4 and optical density (OD) was measured after 20 min at 492 nm.", "Pooled sera from M. tuberculosis culture positive patients were used as positive control (OD>1.0).", "Antigen-specific responses were expressed as relative titers, which were defined as the optical density multiplied by the dilution factor of the specimen [36].", "Statistical Analysis Statistical analyses were carried out using the SigmaStat software (Jandel Scientific, San Rafael, Calif.).", "Comparisons between the groups were made using the One Way Analysis of Variance (ANOVA) or ANOVA on ranks as appropriate.", "P-values were considered significant when ≦0.05.", "Receiver-operator characteristic (ROC) curves were constructed to describe the relation between the sensitivity and specificity at varying cutoff levels of BCG- or PPD-specific IgG titers in lymphocyte secretions (ALS).", "Results Demography of Patients Forty-nine patients with suspected pulmonary TB were recruited from Institute of Diseases of the Chest and Hospital (IDCH).", "Only those patients who had two consecutive-sputum specimens positive for acid-fast bacilli (AFB) were included in the study.", "Out of 49 patients with smear positive pulmonary TB, 45 patients were culture positive for M. tuberculosis (92%) and 2 had contaminated culture and 2 were culture negative.", "All patients received the standard treatment and for therapy-resistant cases, the treatment was modified.", "Median age of the patients was 30 years with a range of 18 to 57 years.", "Thirty-six of forty-nine TB patients were males and thirteen were females.", "Among them, thirty-five were BCG vaccinated (having a BCG scar).", "Patients with non-tuberculosis illness (n=35) included patients with bronchiectasis (n=22), lung cancer (n=7), lung abscess (n=4) and aspergillosis (n=2).", "The diagnosis was confirmed by histology or cytology.", "Thirty-five healthy individuals (laboratory personnel) were included in the study as healthy controls all of whom except one were BCG vaccinated.", "Lymphocyte Numbers and Supernatant Dilution.", "Culture supernatants from different concentrations of cell suspensions and different incubation time points were used to determine antigen-specific IgG titers.", "With higher concentration of PBMC, higher BCG-specific IgG titers were obtained ( FIG. 1 ).", "BCG-specific IgG titers were significantly higher in supernatants of 2, 5 and 10 million cells compared to that in 1 million cells (P<0.001).", "For 2 to 10×10 6 PBMC/ml, the supernatants need to be diluted 2-4 times.", "However with the cell concentration of 1×10 6 PBMC/ml, undiluted supernatants had to be used.", "Since the PBMC counts are usually low in moderate to severely sick TB patients, we opted for one million cell/ml suspensions.", "BCG- and PPD-Specific Antibodies in Lymphocyte Secretions A gradual increase in relative titers of BCG-specific antibody was found from 48 to 72 hours with a slight decline in the titers at 96 hours ( FIG. 2 ).", "The titers at 24 h were low and only studied in a few subjects.", "The optimum time point was found to be 72 hours.", "Pulmonary TB patients had significantly higher BCG-specific IgG antibody titers than healthy subjects (P<0.001), and non-TB patients (P<0.001) at all time points ( FIG. 3A ).", "Response to PPD ( FIG. 3B ) was similar to that seen with BCG-vaccine.", "There was no significant difference in the BCG-specific antibody titers between patients with (35 vaccinated;", "geometric mean (GM) of relative titer-0.67) or without BCG vaccination (14 non-vaccinated;", "GM=0.75) (P=0.5).", "Cutoff Level to Define a Positive Test Result ROC curves were constructed from the ALS responses to BCG or PPD comparing TB patients with healthy controls.", "The selection of the best cutoff point value was based on the level at which the accuracy was maximum.", "The best cutoff point was found to be 0.42 with a sensitivity of 92.5% and a specificity of 80% for the BCG-ALS assay ( FIG. 4A ).", "For PPD-specific response, the best cut-off value was 0.32 with a sensitivity of 73% and a specificity of 80% for the ALS assay ( Fig.", "4B ).", "The sensitivity and specificity for BCG-ALS assay were higher than those ofPPD-specific ALS assay.", "The positive predictive value of the assay was 97%.", "Discussion A rapid diagnostic assay that can detect patients with active tuberculosis is urgently needed to control and prevent the spread of pulmonary tuberculosis.", "We report a novel technique to rapidly identify such patients by culturing peripheral blood lymphocytes and detection of tuberculosis-specific antibodies in lymphocyte secretions.", "Comparison between bacteriologically confirmed TB patients and non-tuberculosis patients (having illness in which TB was part of the differential diagnosis) or healthy controls showed a significant difference in the BCG antigen-specific-IgG antibody responses in the secretions.", "The sensitivity and specificity of the test were about 93% and 80% respectively indicating that the combination of the ALS and ELISA assays using BCG vaccine as an antigen would enable rapid detection of M tuberculosis infection (within 4-5 days) in patients with active tuberculosis.", "Prior BCG vaccination did not hamper the test for identification of TB and could successfully differentiate between BCG-vaccinated and M. tuberculosis infected patients.", "The positive predictive value of the test was 97%.", "Detection of antigen specific antibody secreting cells (ASC) have been used for monitoring therapeutic responses in TB patients [37].", "We evaluated the ALS technique because we hypothesized that active tuberculosis would provide continuous antigen stimulation resulting in antibody producing cells in circulation.", "By contrast inactive tuberculosis might result in high antibody titers in serum but would be less likely to stimulate antibody producing cells in circulation.", "In addition, it is easier to perform ALS assay and the supernatant can also be stored for future use to detect antigen-specific antibodies, novel antigens, cytokines and other mediators.", "BCG-vaccine and PPD were chosen as antigens for the easy availability and assessment of a broad spectrum of TB-specific antibodies, since they cover a vast array of protein and lipid antigens.", "ALS response to both BCG and PPD were similar however, the sensitivity and specificity of the BCG-specific ALS response were higher.", "Our ongoing follow-up study of family contacts indicates that increased ALS responses to BCG or PPD are associated with increased risk of developing active TB.", "Various purified protein antigens have been tested for diagnostic applications;", "for example, ESAT-6, which is a small molecular weight peptide expressed by M. tuberculosis, M. bovis and M. africanum and is absent from all strains of M. bovis and most of the environmental mycobacteria.", "Recent studies have found ESAT-6 to be a highly promising antigen for immunodiagnosis of active M. tuberculosis infection in nonendemic regions [38-41].", "However, in regions endemic for tuberculosis such as The Gambia, India and Bangladesh, contacts of TB patients had significantly higher ESAT-6 specific response than TB patients [29, 42] thereby limiting the use of the method to nonendemic countries.", "There is a long term persistence of ESAT-6 specific antibodies in patients in remission from pulmonary TB in endemic areas making it difficult to discriminate between latent TB or remission from TB [43].", "In conclusion, the use of the ALS specimens with the standard ELISA technique holds potential as a future TB-specific diagnostic test.", "With the extensive availability of ELISA technology in developing country settings, this method should be applicable both in developing countries endemic for TB as well as industrialized countries for screening of suspected patients.", "Since this method does not require specimen from the site of disease, it should also be useful in diagnosis of paucibacillary childhood TB.", "References cited herein are listed below for convenience.", "WHO report 1999.", "Global Tuberculosis Control: Communicable Diseases, WHO.", "Geneva: World Health Organization, 1999.", "Director General (DG) Health Services: Report on the national prevalence survey on tuberculosis in Bangladesh, 1987-88.", "Dhaka: Dhaka: Ministry of Health and Family Welfare.", "1989.", "Kumaresan J A R M, Murray C J L. 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CROSS-REFERENCE TO RELATED APPLICATION [0001] The present application claims priority of U.S. provisional application Ser. No. 60/532,289, filed Dec. 23, 2003. [0002] The present invention was made with the support of the United States Air Force, Contract No. F496200210205 and National Science Foundation Contract No. CTS0210005. The U.S. Government has certain rights in the invention. BACKGROUND OF THE INVENTION [0003] The layer-by-layer (LbL) assembly [1] , which is based on alternating electrostatic adsorption of oppositely charged materials (polyelectrolytes [1] , dendrimers [2] , proteins [3] , clays [4] , and nanoparticles [5,6] ), has been applied for the fabrication of a wide variety of functional ultrathin organized films. [7] These films with tunable internal multilayered organization have potential applications in nanoelectronic, optoelectronic, and magnetic technologies, as well for opto-mechanical, chemical and bio sensing, and nanotribology. [8,9] [0004] Recently, a new approach of a spin self-assembly [10] or spin-assembly [11] was suggested, which combined the spin coating and LbL techniques to make a cost and time-efficient technology for the fabrication of multilayered films from polyelectrolytes, dendrimers, and inorganic nanoparticles on planar substrates. [10,11,12,13] It has been shown that, in the framework of this approach, fast and efficient layer deposition under shear forces resulted in well-ordered multilayered structures with modest non-uniformity of the films and some properties different from “conventional” LbL films. However, this approach was not been used to fabricate multilayered, nanoparticle containing, truly nanoscale LbL films with exceptional mechanical parameters in the most demanding free-suspended or free-standing state where overall integrity and stability of the nanoscale films with macroscopic lateral dimensions play a critical role. Free standing organized organic-inorganic films are considered as prospective sensing compliant membranes for photo, opto, and thermal microdevices. [14] [0005] To date, several different approaches were implemented for the fabrication of free-standing nanoscale films from polymers and inorganic nanoparticles: cast films [15]1 , “growth from” reactions on the patterned surface [16] , cross-linking of amphiphilic Langmuir films [17] , and the deposition of the LbL multilayers onto a sacrificial or pH sensitive substrate. [18,19,20] However, all these approaches included slow (from hours to days) and multistep routines, e.g., in Langinuir approach: monolayer formation, deposition, and crosslinking. Moreover, they multilayer LbL films are either limited to relatively thin 100-300 nm) polymer films or thick (300-5000 nm) composite organic-inorganic (with inorganic particles, platelets, fibers) films with uniformity issues. Usually, the thin LbL films are extremely fragile and corresponding composite films must be prepared relatively thick to accommodate filler irregularities. The mechanical characteristics achievable for these films are characterized by the elastic modulus values of several GPa and ultimate tensile strength of 40-70 MPa with a record value for carbon nanotube thick films of 220 GPa. [19] SUMMARY OF THE INVENTION [0006] The present invention provides a compliant, highly-uniform, extremely robust, smooth, and long-living free standing nanoscale membranes with excellent mechanical characteristics. The present membranes comprise two or more polyelectrolyte multilayers with a central interlayer containing gold nanoparticles ( FIG. 1 a ) having a general cross-sectional formula: [(P cat −P an ) n P cat /Met/(P cat −P an ) n P cat ] m wherein P cat −P an represents a bilayer of a cationic polymer, such as an acid addition salt of a polyamine, and an anionic polymer, such as a polysulfonic acid salt, and Met is a nanoparticle of a metal such as silver or gold; preferably, m is 1-10 and n is 2-50 to yield a film thickness of about 20-500 nm, preferably about 15-250 nm, more preferably about 20-80 nm. Preferably, the membranes are formed by spin-assisted layer-by-layer assembly on a sacrificial substrate layer. [0007] The central metal interlayer can be used in sensors to enhance an optical response and detect surface plasmon resonances from the deflected membranes as will be discussed hereinbelow. Uniform nanoscale films that have a thickness in the range from 20 to 70 nm, depending on the numbers of layers, can be constructed using with a spin-assisted layer-by-layer LbL (SA-LbL) assembly method. The films can be fabricated within several minutes unlike usual methods requiring several hours. The films of the invention can sustain significant, multiple elastic deformations with a life time of at least ten million cycles. The parameters achieved here (the elastic modulus of about 10-50 GPa, e.g., about 30-40 GPa, the ultimate strain of 2%, and the ultimate tensile strength of 130 MPa) surpass those known for much thicker (microns) nanoparticle-containing free standing LbL films. [0008] The membrane of the present invention can be prepared by a process comprising depositing layers of the cationic polymer (P cat ), the anionic polymer (P an ), and the inert nanoparticles layer-by-layer using spin-assisted deposition, onto the surface of a substrate. Preferably the surface has been pre-coated by spin-assisted deposition of a layer of a nonionic polymer that is soluble in an organic solvent that does not dissolve P an or P cat , thus permitting the release of the film post-deposition, by simply dissolving the nonionic polymer. The nonionic polymer can be a polysaccharide, such as a cellulosic polymer, such as cellulose acetate, or other chemically-modified cellulose. The individual polymer layers can be crosslinked if necessary. The substrate can also be inorganic, such as a silicon wafer. [0009] The present invention also provides a detection cell comprising a chamber formed by enclosing (or capping) a channel passing through a solid substrate at one end by a compliant membrane of the invention, and by enclosing (or capping) the channel at the other end by a rigid membrane that is transparent to the energy sought to be detected. The chamber can be cylindrical (the chamber walls can form a cylinder) or can be formed into other shapes as desired. The chamber can be filled with an inert gas such as argon, or with air. [0010] The passage of the energy to be detected, such as photothermal energy, through the rigid membrane and into the chamber, causes a detectable elastic reversible deflection of the compliant membrane, which can be detected and measured by a suitably-placed detection means. The chamber or chambers can be about 0.1-10 μm in diameter, and can be formed as perforations in a planar substrate sheet such as a polysilicon sheet. Thus, a single solid substrate sheet can comprise a plurality of the detection cells of the invention. Preferably, the substrate sheet is about ≦100 nm in thickness. The membrane preferably possesses an elastic modulus of about 10-50 MPa, and can exhibit high absorption in the 8-12 μm wavelength range. BRIEF DESCRIPTION OF THE FIGURES [0011] FIG. 1 a ) Sketch of the microstructure of the free-standing film with a central gold nanoparticle intralayer sandwiched between two symmetrical polymer multilayers (n=3 is selected for illustration); b) large scale topographical image of (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 SA-LbL film on the silicon substrate; c) UV-vis spectrum for (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 demonstrating major adsorption bands caused by PSS adsorption as well as individual and collective surface plasmon resonances within gold nanoparticle intralayer; d) schematic of a free-suspended, highly compliant, multi-layered nano-scale membrane with layered nanoparticle/polymer organization deposited on a perforated substrate. Left: initial planar state. Right: membrane in deflected state, acting as a photo-thermally sensitive element. [0012] FIG. 2 a ) Large scale AFM image of (PAH-PSS) 3 PAH/Au/PAH(PSS-PAH) 3 free-standing film released and lifted-up by a silicon substrate; b) height histogram and the AFM image of the released SA-LbL film edge used to obtain the thickness and microroughness of the film; c) high-resolution AFM topographical image of (PAH-PSS) 3 PAH/Au/PAH(PSS-PAH) 3 free-standing film released and lifted-up by a silicon substrate; d) thickness of the SA-LbL free-standing films as a function of the number of polymer bilayers. [0013] FIG. 3 a ) Photograph of a released piece of (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 film on the water surface; b) Top view photograph of (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 SA-LbL film lifted-up by the 100 μm copper grid, several cells with broken film are indicated with white arrows; c, d) side view of the free-standing film that deformed by different pressures applied from below; e) the elastic deflection of the central part of 600 μm free-standing film under different pressure measured experimentally (squares) and a corresponding theoretical fit (line). [0014] FIG. 4 ( a ). Scheme of fabrication of gold nanoparticles-polyelectrolytes multilayers. a) assembly of PEI monolayer on a silicon wafer; b) gold nanoparticle monolayer deposited by adsorption on PEI surface; c) Au/(PAH-PSS) n PAH multilayers fabricated with SA LBL assembly of polyelectrolyte layers; d) assembly of [Au/(PAH-PSS) n PAH] 2 multilayer structure; FIG. 4 ( b ). Scheme of fabrication of free-standing film. [0015] FIG. 5 . a) AFM topographical image of well-separated larger gold nanoparticles, diameter: 12.7±1.3 nm; b) AFM topographical image of smaller gold nanoparticles, diameter: 2.3±1.2 nm; c) height histogram of gold nanoparticles with the diameter of 12.7±1.3 nm obtained from AFM data; d) UV-visible extinction spectrum of larger and smaller gold nanoparticle solutions. [0016] FIG. 6 . AFM topographical images of gold nanoparticle monolayer with different surface coverage fabricated by using different concentrations of solution, z-scale is 30 nm: a) the lowest surface coverage obtained from 1.5×10 −10 mol/L solution; b) low surface coverage of 2% obtained from 1.5×10 −9 mol/L solution; c) the highest surface coverage of 22% obtained from 1.5×10 −8 mol/L solution; d) larger scale area of same sample as c; e, f) high resolution topographical image (300×300 nm) of gold nanoparticles with surface coverage of 8% obtained with conventional silicon tip (e) and carbon nanotube tip (f). The appearance of nanoparticles is affected by the tip dilation, which is sensitive to a low point between particles reachable by the tip. [0017] FIG. 7 . Top: UV-visible extinction spectra of gold nanoparticle monolayers with different surface coverages. Bottom: the variation of positions of two resonance bands and their intensity ratio. [0018] FIG. 8 . AFM topography image and line scan profile of Au/(PAH-PSS)PAH multilayered films. a) large scale AFM image; b) higher resolution AFM image; c) AFM image of the film edge; d) cross-section of the image (c). Z scale is 30 nm. [0019] FIG. 9 . a) UV-visible extinction spectra of Au/(PAH-PSS) n PAH multilayers, with n of 1, 3 and 5, respectively. Gold nanoparticle surface coverage is 5%. b) The variation of plasmon resonance peak positions and their intensity ratio (the intensity of second to first plasmon peak). [0020] FIG. 10 . AFM topographical images of [Au/(PAH-PSS) 5 PAH] 2 film, z-scale is 30 nm. a) higher-resolution image, b) large scale image; c) the variation of the film thickness for [Au/(PAH-PSS) n PAH] m for different combinations of n and m. Two data points for m=3 are presented for illustrative purposes. [0021] FIG. 11 . Top: UV-visible extinction spectrum of [Au/(PAH-PSS) n PAH] 2 film with 22% gold nanoparticle surface density with three major adsorption bands marked. Bottom: a linear increase of the absorption at 225 nm with the bilayer number n. [0022] FIG. 12 . Top: UV-visible extinction spectra of [Au/(PAH-PSS) n PAH] 2 films with high gold nanoparticle density (22% surface coverage), with n equals to 1, 2, 3, and 4. These spectra can be fitted with three Lorentzian peaks, as shown for the n=1. Bottom: the variation of plasmon resonance peak positions and the intensity ratio (the intensity of second to first plasmon peak). [0023] FIG. 13 . Top: UV-visible extinction spectra of [Au/(PAH-PSS) n PAH] 2 films with medium gold nanoparticle density (15% surface coverage), with n equals to 0, 1, 2, 3, 4, and 5. Bottom: the variation of plasmon resonance peak positions and their intensity ratio (the intensity of second to first plasmon peak). [0024] FIG. 14 . Top: UV-visible extinction spectra of [Au/(PAH-PSS) n PAH] 2 films with different gold nanoparticle density. Bottom: the variation of plasmon resonance peak positions and their intensity ratio (the intensity of second to first plasmon peak). [0025] FIG. 15 . Microstructure of the film composed of two gold nanoparticles layers separated by three polymer layers, [Au/(PAH-PSS) 1 PAH] 2 , demonstrating different distance:diameter ratio for intralayer and interlayer distances and used for the estimation of total film thickness. It shows that for incomplete gold nanoparticles layers the thickness of the film with two gold nanoparticles layers is below a doubled value for a single layer. [0026] FIG. 16 . Scheme of apparatus for performing bulge test of supported film. [0027] FIG. 17 . Graph and photomicrographs demonstrating mechanical properties of free-standing films. [0028] FIG. 18 . Graph and diagram depicting micromechanical properties of free-standing films. DETAILED DESCRIPTION OF THE INVENTION [0029] The major sensitive element in the sensor of the present invention is composed of highly compliant, ultrathin (40-400 nm), multilayered elastomeric membrane, with its supporting layer responsible for carrying external loads and providing a free-suspension/non-planar shape, if needed ( FIG. 1 d ). The membrane's mechanosensitive layer is capable of significant reversible deformations, while providing the transduction of mechanical stresses to an external detector ( FIG. 16 ). Initial spacing in the multi-nanolayered membrane can be established during the layer-by-layer fabrication process, with the deposition of alternating layers of nanoparticles and appropriately charged polymer electrolyte. Equilibrium spacing in the free-suspended state gives rise to a characteristic adsorption band in the visible range, which can be detected with UV-Vis spectroscopy. Stretching of the membrane is due to external stimuli (e.g., increasing air pressure in isolated cells of the perforated support (see FIG. 1 d )). This leads to deviation from the initial planar configuration and changes of spacing in the multi-layered structure detectable via surface plasmon spectroscopy. Perforated solid substrates will be selected for their highly planar surfaces, with hole sizes of 0.1 to several tenths of a micrometers up to about 10 μm, and that can be assembled with thin and rigid bottom walls. Such substrates can be micro-fabricated from polysilicon. [0030] Using the present compliant, multi-layered nanoscale membranes as a mechano- and thermosensitive element results in a great increase in the sensitivity of photo-thermal detection. Indeed, current silicon-based, microfabricated photo-thermal Golay cells are capable of detecting temperature gradients with the 0.2 K interval with a resolution surpassing 10 −2 K. Yamashita et al., Sensors & Activators A, 66, 29 (1998). A limiting factor is the brittleness of the silicon membrane, with a maximum deflection of 1 μm (0.03% elastic deformation), which limits the effective temperature window. In addition, the high bending modulus and capacitance detection limits the minimum detectable deflection and volume variation to values above 0.01%. [0031] By contrast, large elastic (reversible) deflections of the sensing element can be easily observed for compliant polymer membranes with multi-nanolayered internal organization, thus expanding the detectable temperature window tremendously. W. A. Goedel et al., Langmuir, 14, 3470 (1998). For compliant membranes, temperature parameters may be estimated from the equation for pressure-deflection relationships in a free-suspended circular membrane: ΔP= 8 Eh (Δ d ) 3 /3(1 −v ) a 4   (1) where ΔP is pressure applied/detected, E is elastic modulus, h is membrane thickness, Δd is membrane deflection, a is membrane diameter, and v is Poisson's ration. V. W. Beems, in Structures and Properties of Thin Films, C. A. Neugebauer et al. eds.) John Wiley (1959) at page 183. Taking the typical dimensions of micro-fabricated Golay cells and the PVT relationship reported before with parameters for compliant materials (i.e., E=10 MPa, v=0.5), one may obtain a theoretical limit of about 10 −5 K for the temperature sensitivity of the compliant membrane, which is several orders of magnitude better than for the present silicon-based Golay cells. [0032] The present invention thus provides for the miniaturization of IR sensors down to a sub-micrometer scale. Indeed, the reduction of the membrane diameter, a, from a “microscopic” millimeter scale in current Si-based design inevitably results in a dramatic decrease in sensitivity, as defined by a given membrane deflection (see equation [1]). For instance, any attempt to miniaturize the silicon-based Golay cell, reducing its diameter to below about 10 μm, would result in increasing its bending stiffniess by six orders of magnitude, which in turn would make this “miniature” cell inoperable. Given that, for compliant, nanometer-thick membranes, the product Eh(Ad) 3 in equation (1) can be reduced by 10-12 orders of magnitude, a manifold increase in sensitivity can be achieved, even for compliant membranes of 1 μm and less in diameter. Thus, this approach promises the prospect of “shrinking” the spatial dimensions of sensors to microscopic proportions, from the current 10 −3 m and 10 −6 m for lateral dimension and thickness, respectively, to 10 μm and <100 nm—a truly nanoscopic scale. This opens a new path for the microfabrication of an array of sensitive elements composed to provide IR imaging capability ( FIG. 1 d ). Having an array of holes with individually suspended sensitive membrane elements, one may address the question of detecting the surface distribution of thermal gradients—and thus realize imaging capabilities unachievable with current Golay design. [0033] Sensitivity limits and covered temperature ranges for Golay cells micro-fabricated with compliant membranes may be estimated using Yamashita's graphical analysis. For identical cell parameters and expanded, detectable deflection limits, one may estimate that minimum recognizable ΔT/T o can be as low as 10 −6 , or ΔT=10 −4 K, and that the temperature window covered will expand to several degrees, instead of the 0.2 K in silicon-based designs of the cell. [0034] The present compliant membranes preferably exhibit high linear elastic deformation to at least 20% (i.e., high bending deformation with linear response); low elastic modulus of 10-50 MPa (to provide low bending resistance at low external pressure); a high Poissson's ration of 0.5 (i.e., low tendency to plastic deformation); high yield strength (to assure low creep at high elastic deformation); and low thermal conductivity (for faster reaction on thermal flux). Secondary properties of the compliant membrane include optical transparency or reflectance (for effective optical detection), and high absorption in the 8-12 μm wavelength range (enhanced sensitivity). Polymers with chemical compositions appropriate for this design will be used as soft interlayers or first “template” layers for multi-nanolayered membranes. [0035] Another major element used to compose inorganic interlayers with distinguishable optical properties will be inorganic nanoparticles such as gold or silver. It is well known that that assemblies of inorganic particles (e.g., gold nanoparticles with diameters of 10-100 nm in dilute solution) show a strong absorption band in the UV-visible wavelength related to plasmon resonance. R. S. Reynolds et al., J. Amer. Chem. Soc., 122, 3795 (2000). ( FIG. 5 .) The position of this band depends upon diameter, the type of packing, and average inter-particle spacing. Organized assemblies from these nanoparticles in solution and in monolayer states show “signature” behavior controlled by level of aggregation. Layer-by-layer (LBL) techniques offer a versatile route to the creation of multi-layered films of nanoparticle materials with controllable composition and film thickness. [0036] For free-suspended membranes with diameters of several micrometers, nanoscale defections will result in significant spacing changes within organized gold nanoparticle interlayers, which can cause a detectable shift of the absorption band on a scale of several nanometers. Optimization of the membrane microstructure in terms of its spacing, particle diameter, number of layers, and matrix compliance should result in increased detection capabilities. Currently, UV-visible spectroscopy is used for detecting the photo-chromic properties of organic monolayers as thin as 2 nm. If necessary, mechanochromic polymers can be included in the inner layer. Other approaches, such as surface plasmon spectroscopy, can be used to detect microstructural variations in the gold-containing interlayer. C. A. Mirkin, Inorg. Chem., 39, 2258 (2000). Mechanochromic polymers have conjugated bonds, and their photochromic response depends upon the conformational status of the macromolecular segments, which may be affected by local mechanical stress. [0037] Alternatively, the compliant interlayer incorporating gold nanoparticle assemblies can be used as a highly reflective layer in a detection scheme based upon laser beam reflection principles. This scheme is widely used in highly sensitive instrumentation such as atomic force microscopes, and allows the detection of minute surface deflections on the scale of a fraction of a nanometer. D. Sarid, Scanning Force Microscopy, Oxford U. Press, New York (1991). The optical reflection scheme with photodiode array used currently for AFM experiments may be modified to measure the vertical deflection of free-suspended membranes. The possibility of a combined detection scheme (e.g., the reflection scheme for nanometer deflections and the absorption scheme for larger membrane deflections) is an option for implementing higher sensitivities and a wider range of detectable temperatures in future research based on this project. [0038] Moderately excessive pressure within the cell will result in the non-planar, dome-like shape of the compliant membrane ( FIG. 1 d ). Such a stressed state is much more sensitive to external variable pressure. Along with thermal flux variations, this non-planar shape can be explored for establishing a stress-mediated regime for the highest sensitivities. Conditions for membrane modulation close to its resonance frequency may be adjusted by varying chopper speed and the membrane's dimensions. Preliminary estimates by effective mass approach show that the principal mechanical resonance of compliant membranes may vary from several Hertz to several thousand Hertz. J. J. Hazel, Thin Solid Films, 339, 249 (1999). Periodic response will be detected in such a state, and any random fluctuations will be canceled out over several cycles. Free-suspended nanoscale membranes can be much more sensitive systems under such stressed conditions, and thus are susceptible to consistent external disturbances. In addition, a stressed membrane produced by controlled variation of excess pressure within the closed cell may maintain the stable, non-planar shape with micrometer-scale diameter, thereby serving as a microresonator for incoming electromagnetic radiation. EXAMPLE 1 [0039] Gold nanoparticle-polymer multilayer films of the general formula (PAH-PSS) n PAH/Au/(PAH-PSS) n PAH which comprise a central gold nanoparticle layer covered with polymer multilayers (n=3-11) were fabricated by SA-LbL method ( FIGS. 4 a - b ). [0040] Gold nanoparticles (12.7±1.3 nm in diameter) were synthesized according to the known procedure. [24] Resulting gold nanoparticles are slightly negatively charged and can be used for electrostatic LbL assembly as was demonstrated elsewhere. [25] Polyelectrolytes, poly(ethylene imine) (PEI M w =25,000), poly(allylamine hydrochloride) (PAH, M w =65,000), and poly(sodium 4-styrenesulfonate) (PSS, M w =70,000) were purchased from Aldrich and used as received. For SA-LBL deposition, PEI (1%), PAH (0.2%), and PSS (0.2%) solution were prepared with Nanopure water (18MΩ·cm). Silicon wafers with typical size 10×20 mm were immersed in piranha solution for 30 minutes and then rinsed throughout with pure water before used according to the usual procedure. [26] For SA-LBL deposition the method described earlier was used [10,11] : A 150 μL polymer solution was dropped onto the substrate and the substrate was rotated at 3000 rpm for 15 seconds. Then the substrate was rinsed twice with Nanopure water and dried with spinning (ca. 30 seconds). All routines for film fabrication were conducted under Cleanroom class 100 conditions to avoid contamination with dust microparticles usually observed when functionalized surfaces are exposed to ambient air. [0041] For free-standing film fabrication, a method introduced by Kotov et al. [18] , was used in which cellulose acetate (CA) is used as a sacrificial layer prepared as cast films. However, to enhance in-plane uniformity of the LbL films, spin-coating was used to apply the polymer layers to a spin-deposited ultrathin layer of CA on a silicon wafer. Free standing LbL films were prepared with the following operations: (a) spin coating the CA layer from a 1% acetone solution; (b) deposition of (PAH-PSS) n PAH multilayers with SA-LBL method; (c) deposition of gold nanoparticles with either spin-assisted or with conventional LbL assembly to reach a higher surface coverage, (d) additional deposition of (PAH-PSS) n PAH multilayers; (e) immersion the film on the substrate in acetone to dissolve the underlying CA layer. In the course of the release procedure, the ultrathin multilayered films containing gold nanoparticles with a general structure (PAH-PSS) n PAH/Au/(PAH-PSS) n PAH, were submerged in the acetone solution. These films were picked up with different solid substrates (usually copper grids with grid dimensions below 100 μm and a copper holder with a central hole of 600 μm in diameter) for further investigations. The SA-LBL films were investigated with atomic force microscopy (AFM) in the tapping mode with Nanoscope IIIA, Dimension 3000 and Multimode microscopes (Digital Instruments, Inc) according to the usual procedure adapted in our laboratory for ultrathin polymer films. [27] Optical properties of gold nanoparticle solutions and the multilayered films on quartz substrates were measured with Shimadzu 1601 UV-visible spectrometer. [0042] All films fabricated showed uniform surface morphology on a large scale (>10 μm across) with only few isolated large surface features and no corrugations and cracks ( FIG. 1 b ). The microroughness of these films still located on the silicon substrate did not exceed 15 nm within the 10×10 μm surface area and was mainly caused by the gold nanoparticles with a diameter of 12.7 nm. UV-vis spectra for the multilayered films showed three major adsorption bands associated with PSS layers, as well as individual and collective surface plasmon resonances generated by gold nanoparticles embedded in a polymer matrix ( FIG. 1 c ). The thickness of the films increased virtually linearly with the number of the polymer layers as expected for the multilayered LbL films. The minimum thickness achieved was 20 nm and it was limited by the presence of the gold nanoparticles as demonstrated in FIG. 1 . [0043] Atomic force microscopy (AFM) imaging of the SA-LbL free suspended films collected on a silicon wafer after release from the sacrificial layer revealed a smooth and uniform surface without large scale corrugations and wrinkles usually observed for conventional free standing composite LbL films ( FIG. 2 a ). Moreover, the surface microroughness decreased slightly to 8-10 nm due to the surface relaxation after the film release. The lateral sizes of the undamaged pieces of the released film can reach 1 cm across. Higher resolution AFM images ( FIGS. 2 b , 2 c ) revealed an intralayer gold nanoparticle aggregation coated with the polymer multilayers in accordance with the microstructure sketch presented in FIG. 1 . The thickness of these released films was measured with the AFM bearing analysis at the film edge areas ( FIG. 2 b ). The height histogram confirmed very good uniformity and flatness of the released films on a large scale and the absence of any significant corrugations, a distinctive feature of the SA-LbL films in comparison with conventional free-suspended LbL films containing inorganic particles. The film thickness increased with a number of deposited layers and followed a linear relationship, a signature of well-ordered, multilayered films ( FIG. 2 d ). The increment was measured to be close to 1.4 nm per polymer layer, which is in agreement with the results on conventional LbL PSS-PAH films on the solid substrates. [0044] As discussed hereinbelow, the SA-LbL films submerged in acetone after release can be transferred onto the water surface. Although the films are less than 70 nm thick, they can be easily observed because of their light-blue color, which comes from the plasmon resonance of dense gold nanoparticles in the film as will be discussed in a separate publication. [21] FIG. 3 a shows the optical image of SA-LbL film with size around 4×4 mm floating on the water surface. [0045] Several channel-containing or “holey” substrates like single-hole plates and normal copper grids can be used to pick up the films, which are very stable under normal condition without any support. When films are used to cover a 600 μm diameter hole no breaking or other damage occurs for at least a month. SA-LbL films suspended over smaller size holes, keep their characteristics for many months. FIG. 3 b shows the image of SA-LbL film on the 200 mesh grid with the cell dimensions of 100×100 μm, which had been kept under normal condition for 3 months. The majority of the rectangular cells of the grid were covered with the uniform SA-LbL film, which is brighter than other areas due to the light reflection enhanced by the presence of the gold nanoparticle intralayer. At the left part of the image, several areas of the film were broken during the lifting process (see an arrow pointing on such an area). These free-standing films were very robust and could be stored under ambient conditions for several months without losing their elastic properties. The minimum overall thickness of the SA-LbL films we were able to release and transfer were about 20 nm. This includes the gold nanoparticles intralayer that is 12.7 nm thick and, thus, only about 9 nm of the surrounding polymer layers was contributed by 10-15 polymer chains ( FIG. 1 ). [0046] Despite this nanoscale thickness, the SA-LbL free-suspended films fabricated here were capable of sustaining significant and repeatable mechanical deformations as were probed with a bulging test as described in detail in literature. [17,22,23] This test was performed with the free-standing film covering a 600 μm diameter hole by applying a hydrostatic pressure from one side to the film and detecting its deflection with an optical microscope ( FIG. 1 b ). FIGS. 3 c and 3 d show the side view optical images of the SA-LbL film with two different pressures. The film deformation can be clearly observed with the film displacement reaching 50 μm for the pressure reaching 4.0 kPa. This displacement corresponds to the relatively high mechanical strain of up to 1.5%. This deformation was completely reversible and the film underwent a complete transformation into a flat state when the pressure was released. This test can be repeated in multiple cycles without damaging the free standing film. These results confirmed AFM observations discussed above regarding the high uniformity and integrity of extremely thin nanoparticle-containing films obtained with the SA-LbL assembly. Detailed studies accomplished in accordance with J. J. Vlasak et al., J. Mater. Res., 7, 3242 (1992) (Ref. 23), demonstrated that film deflection indeed followed a power law expected for the uniform elastic deformation of thin film as will be discussed hereinbelow (see data and fit in FIG. 3 e ). [0047] These measurements show that the elastic modulus values can reach 30-40 GPa for elastic deformations as high as 2%. The ultimate tensile strength as high as 130 MPa was reached as well. Moreover, considering that without external pressure but under influence of external fluctuations (acoustic noise) the free-standing films show random deviations of about 1 μm with a frequency of about 5 Hz and are stable under these conditions for more than a month, a life time of about ten million cycles can be estimated. These are record parameters, which far exceed mechanical parameters reported to date and are close to that demonstrated for relatively thick (up to microns) nanofiber-reinforced LbL films, and far exceed mechanical parameters reported to date and are close to that demonstrated for relatively thick (up to microns) nanofiber-reinforced LbL films. [19] REFERENCES [0000] [1 ] Y. Lvov, G. Decher, H. Möhwald, Langmuir 1993, 9, 481. Y. Lvov, K. Ariga, I. Ichinose, T. Kunitake, J. Am. Chem. Soc. 1995, 117, 6117. G. Decher, Y. Lvov, J. Schmitt, Thin Solid Films 1994, 244, 772. M. Yu, Y. Lvov, D. Decher, Crystallography Reports 1994, 39, 628. S. Y. Yang, M. F. Rubner, J. Am. 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Symp. 2002, 177, 175. F. Mallwitz, W. A. Goedel, Angew. Chem. Int. Ed. 2001, 40, 2645. W. A. Goedel, R. Heger, Langmuir 1998, 14, 3470. [18] A. A. Mamedov, N. A. Kotov, Langmuir 2000, 16, 5530. [19] A. A. Mamedov, N. A. Kotov, M. Prato, D. M. Guldi, J. P. Wicksted, A. Hirsch, Nature Mater. 2002, 1, 190. Z. Tang, N. A. Kotov, S. Magonov, B. Ozturk, Nature Mater. 2003, 2, 413. [20] S. T. Dubas, T. R. Farhat, J. B. Schlenoff, J Am. Chem. Soc. 2001, 123, 5368. [21] C. Jiang, S. Markutsya, V. V. Tsukruk, Langmuir submitted. [22] J. W. Beams, in Structure and Properties of Thin Solid Films , (Eds: C. A. Neugebauer, J. B. Newkirk, D. A. Vermilyea), John Wiley: New York 1959, p 183. [23] J. J. Vlasak, W. D. Nix, J Mater. Res. 1992, 7, 3242. [24] Grabar, K. C.; Freeman, R. G.; Hommer, M. B.; Natan, M. J. Anal. Chem. 1995, 67, 735. [25] C. Jiang, S. Markutsy, V. V. Tsukruk, Polymer Materials: Sci. & Eng. 2003, 89, 346. [26] V. V. Tsukruk, V. N. Bliznyuk, Langmuir 1998, 14, 446. [27] V. V. Tsukruk, Rubber Chem. Technol. 1997, 70, 430. V. V. Tsukruk, D. H. Reneker, Polymer, 1995, 36, 1791. EXAMPLE 2 Collective and Individual Plasmon Resonances in Nanoparticle Films Obtained by Spin-Assisted Layer-by-Layer Assembly [0000] Experimental [0075] Reagents and Materials. Polymer for LbL assembly, namely, poly(ethylene imine) (PEI, M w =25 000), poly(allylamine hydrochloride) (PAH, M w =65 000), and poly(sodium 4-styrenesulfonate) (PSS, M w =70 000) were purchased from Aldrich and used without further purification. Ultra-pure water with a resistivity of 18 MΩ·cm used in all experiments was purified with a Nanopure® system. Quartz substrates were cleaned with a fresh Royal solution (HNO 3 :HCl, V:V=1:3). Silicon wafers cut to a typical size of 10×20 mm were cleaned in a piranha solution (H 2 SO 4 :H 2 O 2 , V:V=1:3), according to a usual procedure adapted in our laboratory. [33] Attention: Royal and Piranha solutions are extremely dangerous and should be very carefully treated. Silicon wafers of the {100} orientation with one side polished (Semiconductor Processing, Co.) and quartz plates with both sides polished (Chemglass Co.) were atomically smooth. After cleaning, the substrates were then rinsed thoroughly with Nanopure water and dried with dry nitrogen before used. [0076] Fabrication of gold nanoparticles/LbL multilayers. Gold nanoparticles of different diameters from 2 to 25 nm were prepared according to the known procedure described in the literature. [34,35] Small size particles were synthesized by using thiocyanate as a reducing agent, while larger nanoparticles were obtained by using sodium citrate. For example, particles with 12.7 nm diameter used throughout in this study were synthesized as follows: 5 mL 1% sodium citrate solution was quickly injected into 50 mL of 1 mM HAuCl 4 boiling solution. The solution was kept under boiling conditions for 10 min and continuously stirred for an additional 15 min. Gold nanoparticle solutions were stored at room temperature in a dark area and used within 3 weeks. Sodium citrate left in the solution after the synthesis of gold particles surrounds the gold nanoparticles so that they are quite stable in solution. These nanoparticles bear modest negative charge under normal pH conditions. [16,36] [0077] For initial modification of the silicon surface, freshly cleaned substrates were first immersed in 1% PEI solution for 15 min to form a polyelectrolyte monolayer with a thickness of about 1 nm. After activation with HCl solution, the slightly positively charged substrates were immersed in gold nanoparticle solution for a certain time period ranging from 1 to 30 min to facilitate electrostatically driven adsorption. Then, the substrates were rinsed with pure water to remove the loosely tethered particles. [0078] The multilayered films with different thicknesses were fabricated by the spin-assembly or spin-assisted LbL (SA-LbL) method, which is a combination of spin-coating and conventional LbL techniques. Spin-assisted LbL technique has been recently introduced as a time- and cost efficient assembly and successfully applied to a range of polyelectrolytes and nanoparticles. [37,38] The thickness of the deposited layers can be controlled by solvent evaporation, spin speed, spin time, and solute concentration. [39] We applied SA-LbL to construct polymer multilayers and nanoparticle-containing layers with low density of nanoparticles. However, conventional LbL was exploited to deposit high-density nanoparticle interlayers. This way, we fabricated [Au(PAH-PSS) n PAH] m films as presented in FIG. 4 . According to usual LbL terminology, n (ranging from 0 to 15) corresponded to the number of polymer bilayers and m (ranging from 1 to 3) corresponded to the number of gold nanoparticle/polymer bilayers. Polyelectrolytes were dissolved in Nanopure water with 0.2% concentration. In the course of SA-LbL fabrication, a droplet of 150 μL polyelectrolyte solution was dropped on the silicon substrate and rotated for 20 seconds with 3000 rpm rotation speed. The substrates were rinsed twice by Nanopure water and dried while spinning for 30 seconds. This procedure was repeated until a designed number of the bilayers n was achieved. All SA-LbL films were prepared in a class 100 clean room to avoid contamination and to assure high optical quality of the films. Fabrication time of about 2 minute per bilayer resulted in very time-efficient procedure: films with 10-20 bilayers were fabricated within 20-40 minutes instead of usual 5-10 hours with manual or robotic arm routines. [0079] Optical properties of gold nanoparticle solutions and multilayered SA-LbL films on quartz substrates were measured with Shimadzu 1601 UV-visible spectrometer. Structure characterization was conducted with atomic force microscopy (AFM). AFM topographical and phase images were collected with Dimension or Multimode AFM microscopes (Digital Instrument) in the tapping mode under ambient condition in accordance with a usual procedure adapted in our laboratory. [40] Silicon tips with spring constants of 50 N/m were used for most scans. Tip radii were in the range of 20-40 nm as calculated from the profiles of a reference gold nanoparticle standard. [41] For selected high-resolution images, carbon nanotube tips with tip radius of 5-11 nm (Nanodevices) were used. AFM images were obtained on different scales ranging from 500 nm to 50 μm with a scanning rate of 1 Hz. To obtain the surface microroughness, a 1×1 μm surface area was normally measured. A film thickness was routinely obtained from the bearing analysis of the surface areas with a scratch produced by a sharp steel needle. Independently, the thickness of the polymer multilayers was measured with a Compel Ellipsometer (InOmTech, Inc.). The average thickness of the SiO 2 layer was measured prior to the polymer deposition and used for the analysis of the ellipsometry data with a double-layer model. [42] The refractive indices for polymers and silicon oxides were taken from literature. [43,44] However, it is worth noting that due to the strong absorption, the thickness of films with high-density gold particles cannot be obtained easily from ellipsometry measurement. [0000] Results and Discussions [0080] Monolayer of Gold Nanoparticles. From the analysis of AFM images of the gold nanoparticles, the mean diameter was estimated from surface histograms constructed for at least 50-100 nanoparticles ( FIG. 5 ). After analyzing size distribution and optical properties for several batches of gold nanoparticles with a diameter ranging from 2 nm to 25 nm, for further studies the nanoparticles with the average diameter of 12.7±1.3 nm were selected ( FIG. 5 c ). The nanoparticle diameter and its variation (˜10%) were close to the results from Grabar et al. [34] This selection gave us nanoparticles of reasonable solution concentration, high storage life-time, relatively narrow size distribution, and clear optical response. [0081] The final concentration of gold in the solution was close to 1 mmol/L. Therefore, the aggregation number per particle was about 6×10 4 and the concentration of gold nanoparticles was about 1.5×10 −8 mol/L assuming a complete reaction. UV-visible spectra of these solutions displayed a strong plasmon resonance peak around 519±0.5 nm caused by SPR of individual nanoparticles ( FIG. 5 d ). [45,46] This strong absorption gives the solution of gold nanoparticles characteristic intense burgundy color. [0082] Gold nanoparticles are rarely adsorbed on a bare silicon surface due to unfavorable Coulombic interactions (both surfaces are slightly negatively charged): only 40-50 nanoparticles were found in the surface area of 10×10 μm. The modification of the silicon surface with a positively charged PEI monolayer resulted in efficient, electrostatically driven adsorption of gold nanoparticles: 1200 nanoparticles were found within 1×1 μm on the PEI surface. Additional surface activation by 0.01 mol/L HCl solution resulted in significant increase of the surface coverage: 1800 gold nanoparticles were found within the 1 μm 2 surface area. [0083] To control the gold nanoparticle density (surface coverage and interparticle distance) during the deposition, the assembly on the PEI monolayer was stopped by a “sudden dilute” technique and the substrate was then rinsed and dried. Increasing the deposition time resulted in the higher surface coverage increasing from 250 nanoparticles/μm 2 for short deposition time up to a saturation limit of 1800 particles/μm 2 . The concentration of gold nanoparticles solution is the most important factor affecting the surface coverage ( FIG. 6 ). For the lowest surface coverage tested here, the mean distance between nanoparticles was about 88 nm that exceeded their diameter manifold (distance:diameter ratio of 7:1). For the medium surface coverage of 5-10%, the interparticle distance decreased to 40-50 nm (distance:diameter ratio of 4:1). Finally, at the saturation level, a virtually “complete monolayer” of gold nanoparticles became visible on AFM images ( FIGS. 6 c and 6 d ). Large-scale AFM images showed a smooth, high quality surface with microroughness below 5 nm and absence of microscopic bumps originating from external contaminations. However, this smooth surface morphology at high magnification represented a common AFM artifact associated with tip dilation of the lateral dimensions of nanoscale objects. [47] Misleading AFM images of “complete” monolayers should be treated with great care. This effect is demonstrated in FIGS. 6 e and 6 f , displaying two high-resolution AFM images of the gold nanoparticles obtained with an ordinary silicon tip and a carbon nanotube tip. The dilation effect was much smaller (but still present) on the AFM image obtained with the nanotube tip that allowed evaluation of nanoparticle concentration for the highest surface coverage. This corresponded to the surface coverage of 22% and the average interparticle distance of 26 nm or 2:1 distance-diameter ratio. This distance falls in the range where effective collective SPR between neighboring nanoparticles is expected. Achieving higher surface concentration under these conditions was prevented by repulsive interactions among nanoparticles. This value was relatively high considering that maximum achievable surface coverage that produces 1:1 distance:diameter ratio for different symmetries of particles is within 75-91% and the percolation limit for spherical particles is close to 55%. [48] These parameters can only be reached for lightly charged nanoparticles. [4] [0084] FIG. 7 shows the UV-visible extinction spectra of gold nanoparticle monolayers with different surface coverages. Unlike the spectrum for solution in FIG. 5 , two broad peaks were observed in the region of 500 to 700 nm. These peaks could be clearly separated after background subtraction and fitting with Lorentzian functions as demonstrated for one spectrum in FIG. 7 . The strong and sharp extinction peak, which appeared around 518±0.5 nm with the width of 53 nm, was virtually unchanged for all monolayers and was caused by the plasmon resonance of isolated gold nanoparticles similarly to dilute solutions. The height of this peak showed almost linear increase with the increase of the surface density. [0085] Another broad peak appeared around 615 nm at low surface concentration and was red-shifted to 635 nm for the highest surface coverage ( FIG. 7 ). The appearance of this second peak is associated with interparticle resonances, which strongly depend upon the distance:diameter ratio among other factors. [28,14,49,50] The absorption at this wavelength was very minor for low surface coverage when the distance:diameter ratio was relatively high (4:1 to 7:1) and increased dramatically for the higher surface coverage. It became predominant (integral intensity is 200 higher for the second peak than the first peak) for the 22% surface coverage when the distance:diameter ratio decreased to 2:1. In fact, such a shape was predicted for a pair of nanoparticles when the distance:diameter ratio falls below 2:1 but it is not usually observed because of low surface coverage achieved experimentally. [17,50] A dominance of collective plasmon resonance was observed for monolayers with the distance:diameter ratio below 3:1 ( FIG. 7 ). [0086] Because of insufficient surface coverage and non-uniformity of interparticle distance distribution in a vast majority of experiments, only a gradual red-shifting of a broad peak is usually observed without separation of collective and individual resonances. [17] In contrast, this broad peak was not originated from the red shift of the individual particle plasmon peak but had a composite nature and contained both individual and collective plasmon resonances. [50,51 ] Collective surface plasmon band depends strongly on interparticle separation and, thus, is sensitive to the chemical environment of the particle and its interaction with surroundings. [36,50,52] As shown below, nanoparticle-containing multilayers with sufficiently small interparticle distance produced a strong appearance of the distinctive collective resonance peak, which was sensitive to changing the inter-particle distance of gold nanoparticles within intra- and inter layered structures. [0087] Gold Nanoparticles-Polymer Multilayer Films. The fabrication of the multilayered films began with the deposition of a first polymer bilayer on top of the gold nanoparticle monolayer ( FIG. 4 ). FIG. 8 shows the AFM images of a gold nanoparticle array with PAH-PSS bilayer spin-assembled on top. A large-scale AFM image (10×10 μm) showed uniformity of this film with overall microroughness not exceeding 2.5 nm. Higher-resolution AFM image of the same layer, Au/(PAH-PSS)PAH, showed surface coverage similar to that measured before spin-assembly of top polymer layers. This indicated that the gold nanoparticles were strongly attached to the surface of the PEI monolayer and were not dissolved or washed away during the spin-coating and spin-rinsing. [0088] The surface of the Au/(PAH-PSS)PAH film was relatively rough due to incomplete surface coverage with gold nanoparticles as indicated by significant surface microroughness. As can be seen from the line scan across the scratched film, the gold nanoparticle were covered by PAH-PSS bilayer resulting in a total thickness of nanoparticles aggregates of about 15 nm (the diameter of 12.7 nm+2.3 nm of PAH-PSS bilayer) ( FIG. 8 ). The PAH-PSS bilayer thickness of 2.7 nm was independently obtained from the film areas without gold nanoparticles. The surface microroughness decreased with an additional deposition of the polymer bilayers. Indeed, for the sample Au/(PAH-PSS) 10 PAH, where 10 bilayer were deposited, the multilayer film was very smooth with the microroughness well below 2 nm. [0089] UV-visible spectra of Au/(PAH-PSS) n PAH multilayers measured for 5% surface coverage of gold nanoparticles revealed virtually constant intensity of the red-shifted first peak appearing around 535 nm with exact positions of 532±0.5, 536±0.5 and 538±0.5 nm for Au/(PAH-PSS) n PAH with n equal to 1, 3 and 5, respectively ( FIG. 9 ). These peaks were 13 to 20 nm red-shifted compared to gold nanoparticle solution (519 nm). This red-shift was usually observed for the gold nanoparticles coated with a polymer layer or dissolved in different solvents and is caused by changing dielectric environment. [53,54] For a matrix with a large refractive index, the position of the surface plasmon band would shift to longer wavelength. [30] With increasing the bilayer number, thicker films covering the gold nanoparticle resulted in the further red-shift of the adsorption peak. It should be noted that the second peak for Au/(PAH-PSS) n PAH multilayers changed similarly ( FIG. 9 ). With a larger number of polymer layers deposited on the gold nanoparticles, the intensity increased and the peak was further red-shifted. This can also be explained by the changing interparticle interaction because of the added dielectric layers. However, collective resonance was much more sensitive to the environment composition because red-shifting was more pronounced with the position changing from 630 nm to 720 nm ( FIG. 9 ). Finally, a strong absorption peak appearing around 225 nm was caused by the contribution from the PSS chains and was used here for independent control of polymer layer deposition. [37] The linear increase of that peak with the number of deposited layers was another strong evidence of the multilayer fabrication despite sparse arrangement of the gold nanoparticles. [0090] As a next step, multilayered films were made containing two and three gold layers designed as presented in FIG. 4 . Both large-scale and higher-resolution AFM topography images of [Au/(PAH-PSS) 5 PAH] 2 films with a high density of gold nanoparticles possessed microroughness of 4 nm within 1×1 μm surface areas and a film thickness of 40 nm. The thickness of the multilayered films [Au/(PAH-PSS) n PAH] m changed linearly with the number of polymer bilayers for different combinations of gold nanoparticles and polymer layers for larger n ( FIG. 10 ). Deviations from linear behavior observed for a small number of bilayers can be explained by partially filling the polyelectrolyte into the empty space between the gold nanoparticles. The linear increase is a strong evidence of the formation of the multilayered structure in the films. The slope of the thickness dependence upon a number of polymer bilayers gives the average PAH-PSS bilayer thickness of 3.2 nm in the [Au/(PAH-PSS) n PAH] 2 film for larger n. This value is close to the estimated thickness of the first bilayer (2.7 nm as discussed above) and corresponds to the results of ellipsometry measurement of (PAH-PSS) n multilayers, which were spin-assembled without gold nanoparticles. [25] [0091] UV-visible spectrum of the gold nanoparticle-polymer films with high density of gold nanoparticles (22% surface coverage) is shown in FIG. 11 . Three clear peaks can be obviously observed for [Au/(PAH-PSS) n PAH] 2 film. The peak at 225 nm showed a linear increase of the PSS material with increasing number of deposited bilayers ( FIG. 11 b ). The intensity of strong plasmon resonance of individual nanoparticles at 540 nm was twice that for [Au/(PAH-PSS) n PAH] films with a single gold nanoparticle layer, which indicates good reproducibility in the deposition of the second gold-containing layer. The strong collective resonance peak appeared at 640 nm. This peak was also observed for gold nanoparticle monolayers and was associated with interparticle interactions within the layer (intralayer resonance). One can expect that an additional contribution associated with additional interactions between the gold nanoparticles located in adjacent layers (interlayer resonance) can be detected for some multilayer combinations. Such separate contribution are not experimentally observed for such small nanoparticles due, probably, to the masking by very strong intralayer resonance. Thus, a series of multilayers was fabricated with increasing number of polymer bilayers between gold intralayers to assure different intra- and inter-layer spacings that can be instructive in separation of inter- and intra-layer resonance contributions. [0092] The UV spectra of the [Au/(PAH-PSS) n PAH] 2 multilayers with two layers containing 22% gold nanoparticle separated by the polymer interlayer with different thicknesses (n varied from 1 to 4 that corresponds to the thickness changing from 6.6 nm to 27 nm) showed two clear major peaks with a significant long-wavelength contribution around 800 nm appeared during fitting analysis ( FIG. 12 ). Similar results were obtained for films containing three gold nanoparticle layers [Au/(PAH-PSS) n PAH] 3 . A plasmon band of isolated gold nanoparticles in these films was further red-shifted due to the presence of additional polymer layers and appeared around 548 nm. The collective plasmon resonance peak appeared in the range of 630-640 nm, as was observed before. This peak is very broad with long-lasting right shoulder ( FIG. 12 ). [0093] Similar spectra were observed for the [Au/(PAH-PSS) n PAH] 2 film with lower concentration of gold nanoparticles ( FIG. 13 ). For the film with a single polymer layer between the two gold nanolayers (n=0), we observed a very strong plasmon peak at 656 nm with its intensity 8 times higher than the intensity of individual plasmon resonance. Increasing a separation between gold-containing nanolayers caused decreasing intensity and a blue-shift of this peak ( FIG. 13 ). The position of this maximum and its intensity became similar to that observed for the gold nanoparticle monolayer only when distance between layers increased above distance:diameter ratio of 2:1. [0094] To clarify this behavior and verify the nature of observed long-wave resonance, several new [Au/(PAH-PSS) n PAH] 2 films with gold layers separated by three polymer layers (about 7 nm thick) were prepared by using solutions with different concentrations of gold nanoparticles ( FIG. 14 ). Indeed, only an individual plasmon peak was observed for the multilayers with an average intra-layer distance:diameter ratio between 4:1 and 7:1. Obviously the very low overall concentration of gold nanoparticles was not sufficient to generate any collective resonances. For multilayers with a higher concentration of gold nanoparticles (distance:diameter ratio of 3:1 and lower), an additional contribution in the range of 600-660 nm showed up with a clearly separated second, red-shifted peak appearing for gold nanoparticle content of 15% and higher (distance:diameter ratio of 2.5:1 and 2:1) ( FIG. 14 ). Optical data obtained for selected [Au/(PAH-PSS) n PAH] 3 films followed general trends described above. [0095] However, what is more important is the-clear appearance of a long-wavelength contribution for higher concentration of gold nanoparticles, which showed up as a wide peak at 780-790 nm similarly to that appeared on the fitting result in FIG. 12 ( FIGS. 12-14 ). The maximum contribution of this additional peak (reaching up to 40% of integral intensity) revealed for the multilayered film with two polymer bilayers between gold layers. This contribution decreased for both smaller and larger separations of gold layers to below 20% of integral intensity suggesting that the optimized interlayer distance of about 6 nm is required to enhance the appearance of interlayer resonance for the films studied here. These changes (intensity and maximum position) directly related to the variation of the interlayer spacing while the intralayer spacing remains unchanged directly suggest the presence of a strong contribution from interparticle resonances between gold nanolayers in addition to intralayer resonance discussed above. This phenomenon confirms the suggestion made above on the presence of the independent contribution originating from collective resonance between gold nanoparticles, which belong to different interlayers in the multilayer films (interlayer collective resonances) in addition to usually observed intralayer collective resonances. [0096] Film microstructure and optical properties. The results on optical properties presented above can be understood considering the real microstructure of gold multilayers derived from AFM data. The sketch of [Au/(PAH-PSS) n PAH] 2 film with the distance:diameter ratio of 2:1 is presented in FIG. 15 . The formation of bi-layered gold films with incomplete surface coverage and a small number of polymer bilayers in-between inevitably goes through a stage of “filling” of the “empty” space available within the first deposited gold nanoparticle monolayer. In this case, the polymer layers form shells around gold nanoparticles with the thickness controlled by a number of bilayers in the manner presented in FIG. 15 . Estimated total thickness of the two layer gold nanoparticle film with three polymer layers between them and parameters obtained from experimental data is about 32 nm, which is fairly close to the experimental result of 38 nm ( FIG. 10 ). [0097] For this microstructure, distance:diameter ratio is determined by equation 1+nL/D where L is the thickness of a polymer layer and D is the diameter of gold nanoparticles. Considering that, for a small number of layers, the thickness of the individual polymer layer is about 1.4 nm, we can estimate distance:diameter ratio for this microstructure to be close to 1.3:1. For this ratio, a strong collective resonance contribution in the range of 800 nm was both predicted theoretically and observed experimentally for metal nanoparticles with larger diameters. [28,55] In thicker films, gradual increase of the separation between gold-containing layers causes an increasing distance:diameter ratio to values close to intralayer values and, thus, gradual disappearance of this contribution for thicker films. It is obvious that achieving higher nanoparticle density and reaching its theoretical percolation limit of 55% for 2D systems of short-range ordered spherical objects [56,57] should result in a much stronger interlayer collective resonance contribution and clear separation of intralayer and interlayer contributions that is a subject of current investigation. Such a phenomenon, if achieved, can be critical for opto-mechanical sensing applications of gold-containing multilayer films that rely on the detection of changes of local intralayer and interlayer microstructures. [0098] In accord with the present invention, organized multilayer films from inert metal nanoparticles and polyelectrolyte multilayers have been fabricated very time efficiently with LbL and spin-assisted LbL assembly techniques. SA-LbL films [Au/(PAH-PSS) n PAH] m with different designs possessed well organized microstructure with uniform surface morphology and high optical quality. [0099] The present invention thus provides compliant, highly-uniform, robust, smooth, and long-living free standing LbL films with record high mechanical parameters. These are true nanoscale films with an overall thickness ranging from 20 to 70 nm for films with a different number of layers. These free-standing films can be manufactured very time-efficiently with SA LbL assembly with an exceptionally high level of uniformity and integrity. These properties facilitate their ability to sustain multiple elastic deformations unachievable for the multilayered films fabricated with conventional LbL techniques. These unexpected properties are believed to be due to different conformation of the macromolecules adsorbed under the conditions of the shear stresses and adapting a much more spread state allowing for more uniform in-plane coverage of the stratified interfaces. The parameters achieved here for these nanoscale free-standing films (the elastic modulus of 30-40 GPa, the ultimate strain of 2%, and the ultimate tensile strength of 130 MPa) surpass those known for much thicker nanoparticle-containing free standing LbL films reported to date and possess a life time of millions of deformational cycles. [0100] All SA-LbL films showed the strong extinction peak in the range of 510-550 nm, which is due to the plasmon resonance of the individual gold nanoparticles red-shifted because of a local dielectric environment. For films with sufficient gold nanoparticle density within the layers (10-22%), the second strong peak was consistently observed between 620-660 nm, which is due to the collective plasmon resonance from intralayer interparticle coupling. Finally, under certain conditions, interlayer interparticle resonance can be separated as an additional, independent contribution around 800 nm in UV-visible spectra. This observation was obtained for multilayer films with a conventional level of the dense surface coverage (that is within 10-20% surface coverage). [58] The independent and concurrent detection of all individual, intralayer, and interlayer plasmon resonances for carefully designed multilayered films with higher content of gold nanoparticles achievable with LbL assembly can be critical for sensing applications which involve monitoring of opto-mechanical properties of these optically active films. The present invention thus provides a first example of robust, high-sensitive, free-suspended film of this type. EXAMPLE 2—REFERENCES [0000] [4] . Fendler, J. H. Chem. Mater. 2001, 13, 3196. [14] . Félidj, N.; Aubard, J.; Lévi, G.; Krenn, J. R.; Salerno, M.; Schider, G.; Lamprech, B.; Leitner, L. A.; Aussenegg, F. R. Phys. Rev. B 2002, 65, 075419. [16] . Caruso, F.; Spasova, M.; Salgueiriño-Maceira, V.; Liz-Marzán, L. Adv. Mater. 2001, 13, 1090; Westcott, S. L.; Oldenburg, S. J.; Lee, T. R.; Halas, N. J. Langmuir 1998, 14, 5396; Gittins, D. I.; Caruso, F. J. Phys. Chem. B 2001, 105, 6846. [17] . Schmitt, J.; Decher, G.; Dressick, W. J.; Brandow, S. L.; Geer, R. E.; Shashidhar, R.; Calvert, J. M. Adv. Mater. 1997, 9, 61. [25] . Decher, G. Science 1997, 277, 1232; Lvov, Y.; Ariga, K.; Ichinose, I.; Kunitake, T. J. Am. Chem. Soc. 1995, 117, 6117; Lvov, Y.; Decher, G.; Möhwald, H. Langmuir 1993, 9, 481; Decher, G.; Lvov, Y.; Schmitt, J. Thin Solid Films 1994, 244, 772; Lvov, Y.; Decher, D. Crystallography Reports, 1994, 39, 628. [28] . Rechberger, W.; Hohenau, A.; Leitner, A.; Krenn, J. R.; Lamprecht, B.; Aussenegg, F. R. Opt. Commun. 2003, 220, 137. [30] . Mulvaney, P. Langmuir 1996, 12, 788. [31] . Sastry, M.; Gole, A.; Patil, V. Thin Solid Films 2001, 384, 125. [32] . Taleb, A.; Petit, C.; Pileni, M. P. J. Phys. Chem. B 1998, 102, 2214. [33] . Tsukruk, V. V.; Bliznyuk, V. N. Langmuir, 1998, 14, 446. [34] . Grabar, K. C.; Freeman, R. G.; Hommer, M. B.; Natan, M. J. Anal. Chem. 1995, 67, 735. [35] . Johnson, S. R.; Evans, S. D.; Mahon, S. W.; Ulman, A. Supermolecular Sci. 1997, 4, 329. [36] . Malikova, N.; Pastoriza-Santos, I.; Schierhom, M.; Kotov, N. A.; Liz-Marzán, L. Langmuir, 2002, 18, 3694. [37] . Cho, J.; Char, K,; Hong, J.-D.; Lee, K.-B. Adv. Mater., 2001, 13, 1076. [38] . Chiarelli, P. A.; Johal, M. S.; Casson, J. L.; Roberts, J. B.; Robinson, J. M.; Wang, H.-L. Adv. Mater. 2001, 13, 1167. [39] . Chiarelli, P. A.; Johal, M. S.; Holmes, D. J.; Casson, J. L.; Robinson, J. M.; Wang, H.-L. Langmuir, 2002, 18, 168. [40] . Tsukruk, V. V.; Reneker, D. H. Polymer 1995, 36, 1791. Tsukruk, V. V. Rubber Chem. Techn. 1997, 70, 430. Ratner, B.; Tsukruk, V. V., Eds. Scanning Probe Microscopy of Polymers, ACS Symposium Series 1998, 694. [41] . Vesenka, J.; Manne, S.; Giberson, R.; Marsh, T.; Henderson, E. Biophysical J. 1993, 65, 992. [42] . Azzam, R. M. A.; Bashara, N. M. Ellipsometry and Polarized Light . Amsterdam; New York: North-Holland Pub. Co. 1977. [43] . Aranishi, Y.; Takahashi, H. Jpn. Kokai Tokkyo Koho 2000, 6. [44] . Van Krevelen, D. W. Properties of Polymers , Elsevier, Amsterdam, 1997. [45] . Bohren, C. F.; Huffman, D. R. Absorption and Scattering of Light by Small Particles ; John Wiley and Sons: New York, 1983. [46] . Kreibig, U.; Vollmer, M. Optical Properties of Metal Clusters , Springer Press: Berlin, 1995. [47] . Magonov, S.; Whangbo, M.-H. Surface Analysis with STM and AFM , VCH, Weinheim, 1996. [48] . Karim, A.; Tsukruk, V. V.; Douglas, J. F.; Satija, S. K.; Fetters, L. J.; Reneker, D. H.; [0126] Foster M. D. J. Phys., II, 1995, 5, 1441. [49] . Jensen, T. R.; Malinsky, M. D.; Haynes, C. L.; Van Duyne, R. P. J. Phys. Chem. B 2000, 104, 10549. [50] . Schmitt, J.; Mächtle, P.; Eck, D.; Höhwald, H.; Helm, C. A. Langmuir 1999, 15, 3256. [51] . Westcott, S. L.; Oldenburg, S. J.; Lee, T. R.; Halas, N. J. Chem. Phys. Lett., 1999, 300, 651. [52] . Ung, T.; Liz-Marzán, L. M.; Mulvaney, P. J. Phys. Chem. B 2001, 105, 3441. [53] . Mayya, K. S.; Schoeler, B.; Caruso, F. Adv. Funct. Mater. 2003, 13, 183. [54] . Huang, S.; Minami, K.; Sakaue, H.; Shigubara, S.; Takahagi, T. J. Appl. Phys. 2002, 92, 7486. [55] . Lal, S.; Westcott, S. L.; Taylor, R. N.; Jackson, J. B.; Nordlander, P.; Halas, N. J. J. Phys. Chem. B 2002, 106, 5609. [56] . Kooij, E. S.; Brouwer, E. A. M.; Wormeester, H.; Poelsema, B. Langmuir 2002, 18, 7677. [57] . Yu, A.; Liang, Z.; Cho, J.; Caruso, F. Nano Lett., 2003, 3, 1203. [58] . Schmitt, J.; Decher, G.; Dressik, W. J.; Brandow, S. L.; Geer, R.; Shashidar, R. Calvert, J. M. Adv. Mater., 1997, 9, 61. [0137] All publications, patents and patent applications are incorporated herein by reference. While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for purposes of illustration it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein may be varied considerably without departing from the basic principles of the invention.
A compliant free-standing multilayer membrane is provided of the cross-sectional formula: [( P cat −P an ) n P cat /Met /( P cat −P an ) n P cat ] m wherein (P cat 31 P an ) represents a bilayer of an anionic polymer and a cationic polymer between at least one layer of Met; n is about 1-50, m is about 1-10; Met is an inert metal nanoparticle; P cat is a cationic polymer and P an is an anionic polymer, preferably prepared by a spin-assisted layer-by-layer assembly on a sacrificial substrate layer.
Condense the core contents of the given document.
[ "CROSS-REFERENCE TO RELATED APPLICATION [0001] The present application claims priority of U.S. provisional application Ser.", "No. 60/532,289, filed Dec. 23, 2003.", "[0002] The present invention was made with the support of the United States Air Force, Contract No. F496200210205 and National Science Foundation Contract No. CTS0210005.", "The U.S. Government has certain rights in the invention.", "BACKGROUND OF THE INVENTION [0003] The layer-by-layer (LbL) assembly [1] , which is based on alternating electrostatic adsorption of oppositely charged materials (polyelectrolytes [1] , dendrimers [2] , proteins [3] , clays [4] , and nanoparticles [5,6] ), has been applied for the fabrication of a wide variety of functional ultrathin organized films.", "[7] These films with tunable internal multilayered organization have potential applications in nanoelectronic, optoelectronic, and magnetic technologies, as well for opto-mechanical, chemical and bio sensing, and nanotribology.", "[8,9] [0004] Recently, a new approach of a spin self-assembly [10] or spin-assembly [11] was suggested, which combined the spin coating and LbL techniques to make a cost and time-efficient technology for the fabrication of multilayered films from polyelectrolytes, dendrimers, and inorganic nanoparticles on planar substrates.", "[10,11,12,13] It has been shown that, in the framework of this approach, fast and efficient layer deposition under shear forces resulted in well-ordered multilayered structures with modest non-uniformity of the films and some properties different from “conventional”", "LbL films.", "However, this approach was not been used to fabricate multilayered, nanoparticle containing, truly nanoscale LbL films with exceptional mechanical parameters in the most demanding free-suspended or free-standing state where overall integrity and stability of the nanoscale films with macroscopic lateral dimensions play a critical role.", "Free standing organized organic-inorganic films are considered as prospective sensing compliant membranes for photo, opto, and thermal microdevices.", "[14] [0005] To date, several different approaches were implemented for the fabrication of free-standing nanoscale films from polymers and inorganic nanoparticles: cast films [15]1 , “growth from”", "reactions on the patterned surface [16] , cross-linking of amphiphilic Langmuir films [17] , and the deposition of the LbL multilayers onto a sacrificial or pH sensitive substrate.", "[18,19,20] However, all these approaches included slow (from hours to days) and multistep routines, e.g., in Langinuir approach: monolayer formation, deposition, and crosslinking.", "Moreover, they multilayer LbL films are either limited to relatively thin 100-300 nm) polymer films or thick (300-5000 nm) composite organic-inorganic (with inorganic particles, platelets, fibers) films with uniformity issues.", "Usually, the thin LbL films are extremely fragile and corresponding composite films must be prepared relatively thick to accommodate filler irregularities.", "The mechanical characteristics achievable for these films are characterized by the elastic modulus values of several GPa and ultimate tensile strength of 40-70 MPa with a record value for carbon nanotube thick films of 220 GPa.", "[19] SUMMARY OF THE INVENTION [0006] The present invention provides a compliant, highly-uniform, extremely robust, smooth, and long-living free standing nanoscale membranes with excellent mechanical characteristics.", "The present membranes comprise two or more polyelectrolyte multilayers with a central interlayer containing gold nanoparticles ( FIG. 1 a ) having a general cross-sectional formula: [(P cat −P an ) n P cat /Met/(P cat −P an ) n P cat ] m wherein P cat −P an represents a bilayer of a cationic polymer, such as an acid addition salt of a polyamine, and an anionic polymer, such as a polysulfonic acid salt, and Met is a nanoparticle of a metal such as silver or gold;", "preferably, m is 1-10 and n is 2-50 to yield a film thickness of about 20-500 nm, preferably about 15-250 nm, more preferably about 20-80 nm.", "Preferably, the membranes are formed by spin-assisted layer-by-layer assembly on a sacrificial substrate layer.", "[0007] The central metal interlayer can be used in sensors to enhance an optical response and detect surface plasmon resonances from the deflected membranes as will be discussed hereinbelow.", "Uniform nanoscale films that have a thickness in the range from 20 to 70 nm, depending on the numbers of layers, can be constructed using with a spin-assisted layer-by-layer LbL (SA-LbL) assembly method.", "The films can be fabricated within several minutes unlike usual methods requiring several hours.", "The films of the invention can sustain significant, multiple elastic deformations with a life time of at least ten million cycles.", "The parameters achieved here (the elastic modulus of about 10-50 GPa, e.g., about 30-40 GPa, the ultimate strain of 2%, and the ultimate tensile strength of 130 MPa) surpass those known for much thicker (microns) nanoparticle-containing free standing LbL films.", "[0008] The membrane of the present invention can be prepared by a process comprising depositing layers of the cationic polymer (P cat ), the anionic polymer (P an ), and the inert nanoparticles layer-by-layer using spin-assisted deposition, onto the surface of a substrate.", "Preferably the surface has been pre-coated by spin-assisted deposition of a layer of a nonionic polymer that is soluble in an organic solvent that does not dissolve P an or P cat , thus permitting the release of the film post-deposition, by simply dissolving the nonionic polymer.", "The nonionic polymer can be a polysaccharide, such as a cellulosic polymer, such as cellulose acetate, or other chemically-modified cellulose.", "The individual polymer layers can be crosslinked if necessary.", "The substrate can also be inorganic, such as a silicon wafer.", "[0009] The present invention also provides a detection cell comprising a chamber formed by enclosing (or capping) a channel passing through a solid substrate at one end by a compliant membrane of the invention, and by enclosing (or capping) the channel at the other end by a rigid membrane that is transparent to the energy sought to be detected.", "The chamber can be cylindrical (the chamber walls can form a cylinder) or can be formed into other shapes as desired.", "The chamber can be filled with an inert gas such as argon, or with air.", "[0010] The passage of the energy to be detected, such as photothermal energy, through the rigid membrane and into the chamber, causes a detectable elastic reversible deflection of the compliant membrane, which can be detected and measured by a suitably-placed detection means.", "The chamber or chambers can be about 0.1-10 μm in diameter, and can be formed as perforations in a planar substrate sheet such as a polysilicon sheet.", "Thus, a single solid substrate sheet can comprise a plurality of the detection cells of the invention.", "Preferably, the substrate sheet is about ≦100 nm in thickness.", "The membrane preferably possesses an elastic modulus of about 10-50 MPa, and can exhibit high absorption in the 8-12 μm wavelength range.", "BRIEF DESCRIPTION OF THE FIGURES [0011] FIG. 1 a ) Sketch of the microstructure of the free-standing film with a central gold nanoparticle intralayer sandwiched between two symmetrical polymer multilayers (n=3 is selected for illustration);", "b) large scale topographical image of (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 SA-LbL film on the silicon substrate;", "c) UV-vis spectrum for (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 demonstrating major adsorption bands caused by PSS adsorption as well as individual and collective surface plasmon resonances within gold nanoparticle intralayer;", "d) schematic of a free-suspended, highly compliant, multi-layered nano-scale membrane with layered nanoparticle/polymer organization deposited on a perforated substrate.", "Left: initial planar state.", "Right: membrane in deflected state, acting as a photo-thermally sensitive element.", "[0012] FIG. 2 a ) Large scale AFM image of (PAH-PSS) 3 PAH/Au/PAH(PSS-PAH) 3 free-standing film released and lifted-up by a silicon substrate;", "b) height histogram and the AFM image of the released SA-LbL film edge used to obtain the thickness and microroughness of the film;", "c) high-resolution AFM topographical image of (PAH-PSS) 3 PAH/Au/PAH(PSS-PAH) 3 free-standing film released and lifted-up by a silicon substrate;", "d) thickness of the SA-LbL free-standing films as a function of the number of polymer bilayers.", "[0013] FIG. 3 a ) Photograph of a released piece of (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 film on the water surface;", "b) Top view photograph of (PAH-PSS) 7 PAH/Au/PAH(PSS-PAH) 7 SA-LbL film lifted-up by the 100 μm copper grid, several cells with broken film are indicated with white arrows;", "c, d) side view of the free-standing film that deformed by different pressures applied from below;", "e) the elastic deflection of the central part of 600 μm free-standing film under different pressure measured experimentally (squares) and a corresponding theoretical fit (line).", "[0014] FIG. 4 ( a ).", "Scheme of fabrication of gold nanoparticles-polyelectrolytes multilayers.", "a) assembly of PEI monolayer on a silicon wafer;", "b) gold nanoparticle monolayer deposited by adsorption on PEI surface;", "c) Au/(PAH-PSS) n PAH multilayers fabricated with SA LBL assembly of polyelectrolyte layers;", "d) assembly of [Au/(PAH-PSS) n PAH] 2 multilayer structure;", "FIG. 4 ( b ).", "Scheme of fabrication of free-standing film.", "[0015] FIG. 5 .", "a) AFM topographical image of well-separated larger gold nanoparticles, diameter: 12.7±1.3 nm;", "b) AFM topographical image of smaller gold nanoparticles, diameter: 2.3±1.2 nm;", "c) height histogram of gold nanoparticles with the diameter of 12.7±1.3 nm obtained from AFM data;", "d) UV-visible extinction spectrum of larger and smaller gold nanoparticle solutions.", "[0016] FIG. 6 .", "AFM topographical images of gold nanoparticle monolayer with different surface coverage fabricated by using different concentrations of solution, z-scale is 30 nm: a) the lowest surface coverage obtained from 1.5×10 −10 mol/L solution;", "b) low surface coverage of 2% obtained from 1.5×10 −9 mol/L solution;", "c) the highest surface coverage of 22% obtained from 1.5×10 −8 mol/L solution;", "d) larger scale area of same sample as c;", "e, f) high resolution topographical image (300×300 nm) of gold nanoparticles with surface coverage of 8% obtained with conventional silicon tip (e) and carbon nanotube tip (f).", "The appearance of nanoparticles is affected by the tip dilation, which is sensitive to a low point between particles reachable by the tip.", "[0017] FIG. 7 .", "Top: UV-visible extinction spectra of gold nanoparticle monolayers with different surface coverages.", "Bottom: the variation of positions of two resonance bands and their intensity ratio.", "[0018] FIG. 8 .", "AFM topography image and line scan profile of Au/(PAH-PSS)PAH multilayered films.", "a) large scale AFM image;", "b) higher resolution AFM image;", "c) AFM image of the film edge;", "d) cross-section of the image (c).", "Z scale is 30 nm.", "[0019] FIG. 9 .", "a) UV-visible extinction spectra of Au/(PAH-PSS) n PAH multilayers, with n of 1, 3 and 5, respectively.", "Gold nanoparticle surface coverage is 5%.", "b) The variation of plasmon resonance peak positions and their intensity ratio (the intensity of second to first plasmon peak).", "[0020] FIG. 10 .", "AFM topographical images of [Au/(PAH-PSS) 5 PAH] 2 film, z-scale is 30 nm.", "a) higher-resolution image, b) large scale image;", "c) the variation of the film thickness for [Au/(PAH-PSS) n PAH] m for different combinations of n and m. Two data points for m=3 are presented for illustrative purposes.", "[0021] FIG. 11 .", "Top: UV-visible extinction spectrum of [Au/(PAH-PSS) n PAH] 2 film with 22% gold nanoparticle surface density with three major adsorption bands marked.", "Bottom: a linear increase of the absorption at 225 nm with the bilayer number n. [0022] FIG. 12 .", "Top: UV-visible extinction spectra of [Au/(PAH-PSS) n PAH] 2 films with high gold nanoparticle density (22% surface coverage), with n equals to 1, 2, 3, and 4.", "These spectra can be fitted with three Lorentzian peaks, as shown for the n=1.", "Bottom: the variation of plasmon resonance peak positions and the intensity ratio (the intensity of second to first plasmon peak).", "[0023] FIG. 13 .", "Top: UV-visible extinction spectra of [Au/(PAH-PSS) n PAH] 2 films with medium gold nanoparticle density (15% surface coverage), with n equals to 0, 1, 2, 3, 4, and 5.", "Bottom: the variation of plasmon resonance peak positions and their intensity ratio (the intensity of second to first plasmon peak).", "[0024] FIG. 14 .", "Top: UV-visible extinction spectra of [Au/(PAH-PSS) n PAH] 2 films with different gold nanoparticle density.", "Bottom: the variation of plasmon resonance peak positions and their intensity ratio (the intensity of second to first plasmon peak).", "[0025] FIG. 15 .", "Microstructure of the film composed of two gold nanoparticles layers separated by three polymer layers, [Au/(PAH-PSS) 1 PAH] 2 , demonstrating different distance:diameter ratio for intralayer and interlayer distances and used for the estimation of total film thickness.", "It shows that for incomplete gold nanoparticles layers the thickness of the film with two gold nanoparticles layers is below a doubled value for a single layer.", "[0026] FIG. 16 .", "Scheme of apparatus for performing bulge test of supported film.", "[0027] FIG. 17 .", "Graph and photomicrographs demonstrating mechanical properties of free-standing films.", "[0028] FIG. 18 .", "Graph and diagram depicting micromechanical properties of free-standing films.", "DETAILED DESCRIPTION OF THE INVENTION [0029] The major sensitive element in the sensor of the present invention is composed of highly compliant, ultrathin (40-400 nm), multilayered elastomeric membrane, with its supporting layer responsible for carrying external loads and providing a free-suspension/non-planar shape, if needed ( FIG. 1 d ).", "The membrane's mechanosensitive layer is capable of significant reversible deformations, while providing the transduction of mechanical stresses to an external detector ( FIG. 16 ).", "Initial spacing in the multi-nanolayered membrane can be established during the layer-by-layer fabrication process, with the deposition of alternating layers of nanoparticles and appropriately charged polymer electrolyte.", "Equilibrium spacing in the free-suspended state gives rise to a characteristic adsorption band in the visible range, which can be detected with UV-Vis spectroscopy.", "Stretching of the membrane is due to external stimuli (e.g., increasing air pressure in isolated cells of the perforated support (see FIG. 1 d )).", "This leads to deviation from the initial planar configuration and changes of spacing in the multi-layered structure detectable via surface plasmon spectroscopy.", "Perforated solid substrates will be selected for their highly planar surfaces, with hole sizes of 0.1 to several tenths of a micrometers up to about 10 μm, and that can be assembled with thin and rigid bottom walls.", "Such substrates can be micro-fabricated from polysilicon.", "[0030] Using the present compliant, multi-layered nanoscale membranes as a mechano- and thermosensitive element results in a great increase in the sensitivity of photo-thermal detection.", "Indeed, current silicon-based, microfabricated photo-thermal Golay cells are capable of detecting temperature gradients with the 0.2 K interval with a resolution surpassing 10 −2 K. Yamashita et al.", ", Sensors &", "Activators A, 66, 29 (1998).", "A limiting factor is the brittleness of the silicon membrane, with a maximum deflection of 1 μm (0.03% elastic deformation), which limits the effective temperature window.", "In addition, the high bending modulus and capacitance detection limits the minimum detectable deflection and volume variation to values above 0.01%.", "[0031] By contrast, large elastic (reversible) deflections of the sensing element can be easily observed for compliant polymer membranes with multi-nanolayered internal organization, thus expanding the detectable temperature window tremendously.", "W. A. Goedel et al.", ", Langmuir, 14, 3470 (1998).", "For compliant membranes, temperature parameters may be estimated from the equation for pressure-deflection relationships in a free-suspended circular membrane: ΔP= 8 Eh (Δ d ) 3 /3(1 −v ) a 4 (1) where ΔP is pressure applied/detected, E is elastic modulus, h is membrane thickness, Δd is membrane deflection, a is membrane diameter, and v is Poisson's ration.", "V. W. Beems, in Structures and Properties of Thin Films, C. A. Neugebauer et al.", "eds.) John Wiley (1959) at page 183.", "Taking the typical dimensions of micro-fabricated Golay cells and the PVT relationship reported before with parameters for compliant materials (i.e., E=10 MPa, v=0.5), one may obtain a theoretical limit of about 10 −5 K for the temperature sensitivity of the compliant membrane, which is several orders of magnitude better than for the present silicon-based Golay cells.", "[0032] The present invention thus provides for the miniaturization of IR sensors down to a sub-micrometer scale.", "Indeed, the reduction of the membrane diameter, a, from a “microscopic”", "millimeter scale in current Si-based design inevitably results in a dramatic decrease in sensitivity, as defined by a given membrane deflection (see equation [1]).", "For instance, any attempt to miniaturize the silicon-based Golay cell, reducing its diameter to below about 10 μm, would result in increasing its bending stiffniess by six orders of magnitude, which in turn would make this “miniature”", "cell inoperable.", "Given that, for compliant, nanometer-thick membranes, the product Eh(Ad) 3 in equation (1) can be reduced by 10-12 orders of magnitude, a manifold increase in sensitivity can be achieved, even for compliant membranes of 1 μm and less in diameter.", "Thus, this approach promises the prospect of “shrinking”", "the spatial dimensions of sensors to microscopic proportions, from the current 10 −3 m and 10 −6 m for lateral dimension and thickness, respectively, to 10 μm and <100 nm—a truly nanoscopic scale.", "This opens a new path for the microfabrication of an array of sensitive elements composed to provide IR imaging capability ( FIG. 1 d ).", "Having an array of holes with individually suspended sensitive membrane elements, one may address the question of detecting the surface distribution of thermal gradients—and thus realize imaging capabilities unachievable with current Golay design.", "[0033] Sensitivity limits and covered temperature ranges for Golay cells micro-fabricated with compliant membranes may be estimated using Yamashita's graphical analysis.", "For identical cell parameters and expanded, detectable deflection limits, one may estimate that minimum recognizable ΔT/T o can be as low as 10 −6 , or ΔT=10 −4 K, and that the temperature window covered will expand to several degrees, instead of the 0.2 K in silicon-based designs of the cell.", "[0034] The present compliant membranes preferably exhibit high linear elastic deformation to at least 20% (i.e., high bending deformation with linear response);", "low elastic modulus of 10-50 MPa (to provide low bending resistance at low external pressure);", "a high Poissson's ration of 0.5 (i.e., low tendency to plastic deformation);", "high yield strength (to assure low creep at high elastic deformation);", "and low thermal conductivity (for faster reaction on thermal flux).", "Secondary properties of the compliant membrane include optical transparency or reflectance (for effective optical detection), and high absorption in the 8-12 μm wavelength range (enhanced sensitivity).", "Polymers with chemical compositions appropriate for this design will be used as soft interlayers or first “template”", "layers for multi-nanolayered membranes.", "[0035] Another major element used to compose inorganic interlayers with distinguishable optical properties will be inorganic nanoparticles such as gold or silver.", "It is well known that that assemblies of inorganic particles (e.g., gold nanoparticles with diameters of 10-100 nm in dilute solution) show a strong absorption band in the UV-visible wavelength related to plasmon resonance.", "R. S. Reynolds et al.", ", J. Amer.", "Chem.", "Soc.", ", 122, 3795 (2000).", "( FIG. 5 .) The position of this band depends upon diameter, the type of packing, and average inter-particle spacing.", "Organized assemblies from these nanoparticles in solution and in monolayer states show “signature”", "behavior controlled by level of aggregation.", "Layer-by-layer (LBL) techniques offer a versatile route to the creation of multi-layered films of nanoparticle materials with controllable composition and film thickness.", "[0036] For free-suspended membranes with diameters of several micrometers, nanoscale defections will result in significant spacing changes within organized gold nanoparticle interlayers, which can cause a detectable shift of the absorption band on a scale of several nanometers.", "Optimization of the membrane microstructure in terms of its spacing, particle diameter, number of layers, and matrix compliance should result in increased detection capabilities.", "Currently, UV-visible spectroscopy is used for detecting the photo-chromic properties of organic monolayers as thin as 2 nm.", "If necessary, mechanochromic polymers can be included in the inner layer.", "Other approaches, such as surface plasmon spectroscopy, can be used to detect microstructural variations in the gold-containing interlayer.", "C. A. Mirkin, Inorg.", "Chem.", ", 39, 2258 (2000).", "Mechanochromic polymers have conjugated bonds, and their photochromic response depends upon the conformational status of the macromolecular segments, which may be affected by local mechanical stress.", "[0037] Alternatively, the compliant interlayer incorporating gold nanoparticle assemblies can be used as a highly reflective layer in a detection scheme based upon laser beam reflection principles.", "This scheme is widely used in highly sensitive instrumentation such as atomic force microscopes, and allows the detection of minute surface deflections on the scale of a fraction of a nanometer.", "D. Sarid, Scanning Force Microscopy, Oxford U. Press, New York (1991).", "The optical reflection scheme with photodiode array used currently for AFM experiments may be modified to measure the vertical deflection of free-suspended membranes.", "The possibility of a combined detection scheme (e.g., the reflection scheme for nanometer deflections and the absorption scheme for larger membrane deflections) is an option for implementing higher sensitivities and a wider range of detectable temperatures in future research based on this project.", "[0038] Moderately excessive pressure within the cell will result in the non-planar, dome-like shape of the compliant membrane ( FIG. 1 d ).", "Such a stressed state is much more sensitive to external variable pressure.", "Along with thermal flux variations, this non-planar shape can be explored for establishing a stress-mediated regime for the highest sensitivities.", "Conditions for membrane modulation close to its resonance frequency may be adjusted by varying chopper speed and the membrane's dimensions.", "Preliminary estimates by effective mass approach show that the principal mechanical resonance of compliant membranes may vary from several Hertz to several thousand Hertz.", "J. J. Hazel, Thin Solid Films, 339, 249 (1999).", "Periodic response will be detected in such a state, and any random fluctuations will be canceled out over several cycles.", "Free-suspended nanoscale membranes can be much more sensitive systems under such stressed conditions, and thus are susceptible to consistent external disturbances.", "In addition, a stressed membrane produced by controlled variation of excess pressure within the closed cell may maintain the stable, non-planar shape with micrometer-scale diameter, thereby serving as a microresonator for incoming electromagnetic radiation.", "EXAMPLE 1 [0039] Gold nanoparticle-polymer multilayer films of the general formula (PAH-PSS) n PAH/Au/(PAH-PSS) n PAH which comprise a central gold nanoparticle layer covered with polymer multilayers (n=3-11) were fabricated by SA-LbL method ( FIGS. 4 a - b ).", "[0040] Gold nanoparticles (12.7±1.3 nm in diameter) were synthesized according to the known procedure.", "[24] Resulting gold nanoparticles are slightly negatively charged and can be used for electrostatic LbL assembly as was demonstrated elsewhere.", "[25] Polyelectrolytes, poly(ethylene imine) (PEI M w =25,000), poly(allylamine hydrochloride) (PAH, M w =65,000), and poly(sodium 4-styrenesulfonate) (PSS, M w =70,000) were purchased from Aldrich and used as received.", "For SA-LBL deposition, PEI (1%), PAH (0.2%), and PSS (0.2%) solution were prepared with Nanopure water (18MΩ·cm).", "Silicon wafers with typical size 10×20 mm were immersed in piranha solution for 30 minutes and then rinsed throughout with pure water before used according to the usual procedure.", "[26] For SA-LBL deposition the method described earlier was used [10,11] : A 150 μL polymer solution was dropped onto the substrate and the substrate was rotated at 3000 rpm for 15 seconds.", "Then the substrate was rinsed twice with Nanopure water and dried with spinning (ca.", "30 seconds).", "All routines for film fabrication were conducted under Cleanroom class 100 conditions to avoid contamination with dust microparticles usually observed when functionalized surfaces are exposed to ambient air.", "[0041] For free-standing film fabrication, a method introduced by Kotov et al.", "[18] , was used in which cellulose acetate (CA) is used as a sacrificial layer prepared as cast films.", "However, to enhance in-plane uniformity of the LbL films, spin-coating was used to apply the polymer layers to a spin-deposited ultrathin layer of CA on a silicon wafer.", "Free standing LbL films were prepared with the following operations: (a) spin coating the CA layer from a 1% acetone solution;", "(b) deposition of (PAH-PSS) n PAH multilayers with SA-LBL method;", "(c) deposition of gold nanoparticles with either spin-assisted or with conventional LbL assembly to reach a higher surface coverage, (d) additional deposition of (PAH-PSS) n PAH multilayers;", "(e) immersion the film on the substrate in acetone to dissolve the underlying CA layer.", "In the course of the release procedure, the ultrathin multilayered films containing gold nanoparticles with a general structure (PAH-PSS) n PAH/Au/(PAH-PSS) n PAH, were submerged in the acetone solution.", "These films were picked up with different solid substrates (usually copper grids with grid dimensions below 100 μm and a copper holder with a central hole of 600 μm in diameter) for further investigations.", "The SA-LBL films were investigated with atomic force microscopy (AFM) in the tapping mode with Nanoscope IIIA, Dimension 3000 and Multimode microscopes (Digital Instruments, Inc) according to the usual procedure adapted in our laboratory for ultrathin polymer films.", "[27] Optical properties of gold nanoparticle solutions and the multilayered films on quartz substrates were measured with Shimadzu 1601 UV-visible spectrometer.", "[0042] All films fabricated showed uniform surface morphology on a large scale (>10 μm across) with only few isolated large surface features and no corrugations and cracks ( FIG. 1 b ).", "The microroughness of these films still located on the silicon substrate did not exceed 15 nm within the 10×10 μm surface area and was mainly caused by the gold nanoparticles with a diameter of 12.7 nm.", "UV-vis spectra for the multilayered films showed three major adsorption bands associated with PSS layers, as well as individual and collective surface plasmon resonances generated by gold nanoparticles embedded in a polymer matrix ( FIG. 1 c ).", "The thickness of the films increased virtually linearly with the number of the polymer layers as expected for the multilayered LbL films.", "The minimum thickness achieved was 20 nm and it was limited by the presence of the gold nanoparticles as demonstrated in FIG. 1 .", "[0043] Atomic force microscopy (AFM) imaging of the SA-LbL free suspended films collected on a silicon wafer after release from the sacrificial layer revealed a smooth and uniform surface without large scale corrugations and wrinkles usually observed for conventional free standing composite LbL films ( FIG. 2 a ).", "Moreover, the surface microroughness decreased slightly to 8-10 nm due to the surface relaxation after the film release.", "The lateral sizes of the undamaged pieces of the released film can reach 1 cm across.", "Higher resolution AFM images ( FIGS. 2 b , 2 c ) revealed an intralayer gold nanoparticle aggregation coated with the polymer multilayers in accordance with the microstructure sketch presented in FIG. 1 .", "The thickness of these released films was measured with the AFM bearing analysis at the film edge areas ( FIG. 2 b ).", "The height histogram confirmed very good uniformity and flatness of the released films on a large scale and the absence of any significant corrugations, a distinctive feature of the SA-LbL films in comparison with conventional free-suspended LbL films containing inorganic particles.", "The film thickness increased with a number of deposited layers and followed a linear relationship, a signature of well-ordered, multilayered films ( FIG. 2 d ).", "The increment was measured to be close to 1.4 nm per polymer layer, which is in agreement with the results on conventional LbL PSS-PAH films on the solid substrates.", "[0044] As discussed hereinbelow, the SA-LbL films submerged in acetone after release can be transferred onto the water surface.", "Although the films are less than 70 nm thick, they can be easily observed because of their light-blue color, which comes from the plasmon resonance of dense gold nanoparticles in the film as will be discussed in a separate publication.", "[21] FIG. 3 a shows the optical image of SA-LbL film with size around 4×4 mm floating on the water surface.", "[0045] Several channel-containing or “holey”", "substrates like single-hole plates and normal copper grids can be used to pick up the films, which are very stable under normal condition without any support.", "When films are used to cover a 600 μm diameter hole no breaking or other damage occurs for at least a month.", "SA-LbL films suspended over smaller size holes, keep their characteristics for many months.", "FIG. 3 b shows the image of SA-LbL film on the 200 mesh grid with the cell dimensions of 100×100 μm, which had been kept under normal condition for 3 months.", "The majority of the rectangular cells of the grid were covered with the uniform SA-LbL film, which is brighter than other areas due to the light reflection enhanced by the presence of the gold nanoparticle intralayer.", "At the left part of the image, several areas of the film were broken during the lifting process (see an arrow pointing on such an area).", "These free-standing films were very robust and could be stored under ambient conditions for several months without losing their elastic properties.", "The minimum overall thickness of the SA-LbL films we were able to release and transfer were about 20 nm.", "This includes the gold nanoparticles intralayer that is 12.7 nm thick and, thus, only about 9 nm of the surrounding polymer layers was contributed by 10-15 polymer chains ( FIG. 1 ).", "[0046] Despite this nanoscale thickness, the SA-LbL free-suspended films fabricated here were capable of sustaining significant and repeatable mechanical deformations as were probed with a bulging test as described in detail in literature.", "[17,22,23] This test was performed with the free-standing film covering a 600 μm diameter hole by applying a hydrostatic pressure from one side to the film and detecting its deflection with an optical microscope ( FIG. 1 b ).", "FIGS. 3 c and 3 d show the side view optical images of the SA-LbL film with two different pressures.", "The film deformation can be clearly observed with the film displacement reaching 50 μm for the pressure reaching 4.0 kPa.", "This displacement corresponds to the relatively high mechanical strain of up to 1.5%.", "This deformation was completely reversible and the film underwent a complete transformation into a flat state when the pressure was released.", "This test can be repeated in multiple cycles without damaging the free standing film.", "These results confirmed AFM observations discussed above regarding the high uniformity and integrity of extremely thin nanoparticle-containing films obtained with the SA-LbL assembly.", "Detailed studies accomplished in accordance with J. J. Vlasak et al.", ", J. Mater.", "Res.", ", 7, 3242 (1992) (Ref.", "23), demonstrated that film deflection indeed followed a power law expected for the uniform elastic deformation of thin film as will be discussed hereinbelow (see data and fit in FIG. 3 e ).", "[0047] These measurements show that the elastic modulus values can reach 30-40 GPa for elastic deformations as high as 2%.", "The ultimate tensile strength as high as 130 MPa was reached as well.", "Moreover, considering that without external pressure but under influence of external fluctuations (acoustic noise) the free-standing films show random deviations of about 1 μm with a frequency of about 5 Hz and are stable under these conditions for more than a month, a life time of about ten million cycles can be estimated.", "These are record parameters, which far exceed mechanical parameters reported to date and are close to that demonstrated for relatively thick (up to microns) nanofiber-reinforced LbL films, and far exceed mechanical parameters reported to date and are close to that demonstrated for relatively thick (up to microns) nanofiber-reinforced LbL films.", "[19] REFERENCES [0000] [1 ] Y. 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Reneker, Polymer, 1995, 36, 1791.", "EXAMPLE 2 Collective and Individual Plasmon Resonances in Nanoparticle Films Obtained by Spin-Assisted Layer-by-Layer Assembly [0000] Experimental [0075] Reagents and Materials.", "Polymer for LbL assembly, namely, poly(ethylene imine) (PEI, M w =25 000), poly(allylamine hydrochloride) (PAH, M w =65 000), and poly(sodium 4-styrenesulfonate) (PSS, M w =70 000) were purchased from Aldrich and used without further purification.", "Ultra-pure water with a resistivity of 18 MΩ·cm used in all experiments was purified with a Nanopure® system.", "Quartz substrates were cleaned with a fresh Royal solution (HNO 3 :HCl, V:V=1:3).", "Silicon wafers cut to a typical size of 10×20 mm were cleaned in a piranha solution (H 2 SO 4 :H 2 O 2 , V:V=1:3), according to a usual procedure adapted in our laboratory.", "[33] Attention: Royal and Piranha solutions are extremely dangerous and should be very carefully treated.", "Silicon wafers of the {100} orientation with one side polished (Semiconductor Processing, Co.) and quartz plates with both sides polished (Chemglass Co.) were atomically smooth.", "After cleaning, the substrates were then rinsed thoroughly with Nanopure water and dried with dry nitrogen before used.", "[0076] Fabrication of gold nanoparticles/LbL multilayers.", "Gold nanoparticles of different diameters from 2 to 25 nm were prepared according to the known procedure described in the literature.", "[34,35] Small size particles were synthesized by using thiocyanate as a reducing agent, while larger nanoparticles were obtained by using sodium citrate.", "For example, particles with 12.7 nm diameter used throughout in this study were synthesized as follows: 5 mL 1% sodium citrate solution was quickly injected into 50 mL of 1 mM HAuCl 4 boiling solution.", "The solution was kept under boiling conditions for 10 min and continuously stirred for an additional 15 min.", "Gold nanoparticle solutions were stored at room temperature in a dark area and used within 3 weeks.", "Sodium citrate left in the solution after the synthesis of gold particles surrounds the gold nanoparticles so that they are quite stable in solution.", "These nanoparticles bear modest negative charge under normal pH conditions.", "[16,36] [0077] For initial modification of the silicon surface, freshly cleaned substrates were first immersed in 1% PEI solution for 15 min to form a polyelectrolyte monolayer with a thickness of about 1 nm.", "After activation with HCl solution, the slightly positively charged substrates were immersed in gold nanoparticle solution for a certain time period ranging from 1 to 30 min to facilitate electrostatically driven adsorption.", "Then, the substrates were rinsed with pure water to remove the loosely tethered particles.", "[0078] The multilayered films with different thicknesses were fabricated by the spin-assembly or spin-assisted LbL (SA-LbL) method, which is a combination of spin-coating and conventional LbL techniques.", "Spin-assisted LbL technique has been recently introduced as a time- and cost efficient assembly and successfully applied to a range of polyelectrolytes and nanoparticles.", "[37,38] The thickness of the deposited layers can be controlled by solvent evaporation, spin speed, spin time, and solute concentration.", "[39] We applied SA-LbL to construct polymer multilayers and nanoparticle-containing layers with low density of nanoparticles.", "However, conventional LbL was exploited to deposit high-density nanoparticle interlayers.", "This way, we fabricated [Au(PAH-PSS) n PAH] m films as presented in FIG. 4 .", "According to usual LbL terminology, n (ranging from 0 to 15) corresponded to the number of polymer bilayers and m (ranging from 1 to 3) corresponded to the number of gold nanoparticle/polymer bilayers.", "Polyelectrolytes were dissolved in Nanopure water with 0.2% concentration.", "In the course of SA-LbL fabrication, a droplet of 150 μL polyelectrolyte solution was dropped on the silicon substrate and rotated for 20 seconds with 3000 rpm rotation speed.", "The substrates were rinsed twice by Nanopure water and dried while spinning for 30 seconds.", "This procedure was repeated until a designed number of the bilayers n was achieved.", "All SA-LbL films were prepared in a class 100 clean room to avoid contamination and to assure high optical quality of the films.", "Fabrication time of about 2 minute per bilayer resulted in very time-efficient procedure: films with 10-20 bilayers were fabricated within 20-40 minutes instead of usual 5-10 hours with manual or robotic arm routines.", "[0079] Optical properties of gold nanoparticle solutions and multilayered SA-LbL films on quartz substrates were measured with Shimadzu 1601 UV-visible spectrometer.", "Structure characterization was conducted with atomic force microscopy (AFM).", "AFM topographical and phase images were collected with Dimension or Multimode AFM microscopes (Digital Instrument) in the tapping mode under ambient condition in accordance with a usual procedure adapted in our laboratory.", "[40] Silicon tips with spring constants of 50 N/m were used for most scans.", "Tip radii were in the range of 20-40 nm as calculated from the profiles of a reference gold nanoparticle standard.", "[41] For selected high-resolution images, carbon nanotube tips with tip radius of 5-11 nm (Nanodevices) were used.", "AFM images were obtained on different scales ranging from 500 nm to 50 μm with a scanning rate of 1 Hz.", "To obtain the surface microroughness, a 1×1 μm surface area was normally measured.", "A film thickness was routinely obtained from the bearing analysis of the surface areas with a scratch produced by a sharp steel needle.", "Independently, the thickness of the polymer multilayers was measured with a Compel Ellipsometer (InOmTech, Inc.).", "The average thickness of the SiO 2 layer was measured prior to the polymer deposition and used for the analysis of the ellipsometry data with a double-layer model.", "[42] The refractive indices for polymers and silicon oxides were taken from literature.", "[43,44] However, it is worth noting that due to the strong absorption, the thickness of films with high-density gold particles cannot be obtained easily from ellipsometry measurement.", "[0000] Results and Discussions [0080] Monolayer of Gold Nanoparticles.", "From the analysis of AFM images of the gold nanoparticles, the mean diameter was estimated from surface histograms constructed for at least 50-100 nanoparticles ( FIG. 5 ).", "After analyzing size distribution and optical properties for several batches of gold nanoparticles with a diameter ranging from 2 nm to 25 nm, for further studies the nanoparticles with the average diameter of 12.7±1.3 nm were selected ( FIG. 5 c ).", "The nanoparticle diameter and its variation (˜10%) were close to the results from Grabar et al.", "[34] This selection gave us nanoparticles of reasonable solution concentration, high storage life-time, relatively narrow size distribution, and clear optical response.", "[0081] The final concentration of gold in the solution was close to 1 mmol/L.", "Therefore, the aggregation number per particle was about 6×10 4 and the concentration of gold nanoparticles was about 1.5×10 −8 mol/L assuming a complete reaction.", "UV-visible spectra of these solutions displayed a strong plasmon resonance peak around 519±0.5 nm caused by SPR of individual nanoparticles ( FIG. 5 d ).", "[45,46] This strong absorption gives the solution of gold nanoparticles characteristic intense burgundy color.", "[0082] Gold nanoparticles are rarely adsorbed on a bare silicon surface due to unfavorable Coulombic interactions (both surfaces are slightly negatively charged): only 40-50 nanoparticles were found in the surface area of 10×10 μm.", "The modification of the silicon surface with a positively charged PEI monolayer resulted in efficient, electrostatically driven adsorption of gold nanoparticles: 1200 nanoparticles were found within 1×1 μm on the PEI surface.", "Additional surface activation by 0.01 mol/L HCl solution resulted in significant increase of the surface coverage: 1800 gold nanoparticles were found within the 1 μm 2 surface area.", "[0083] To control the gold nanoparticle density (surface coverage and interparticle distance) during the deposition, the assembly on the PEI monolayer was stopped by a “sudden dilute”", "technique and the substrate was then rinsed and dried.", "Increasing the deposition time resulted in the higher surface coverage increasing from 250 nanoparticles/μm 2 for short deposition time up to a saturation limit of 1800 particles/μm 2 .", "The concentration of gold nanoparticles solution is the most important factor affecting the surface coverage ( FIG. 6 ).", "For the lowest surface coverage tested here, the mean distance between nanoparticles was about 88 nm that exceeded their diameter manifold (distance:diameter ratio of 7:1).", "For the medium surface coverage of 5-10%, the interparticle distance decreased to 40-50 nm (distance:diameter ratio of 4:1).", "Finally, at the saturation level, a virtually “complete monolayer”", "of gold nanoparticles became visible on AFM images ( FIGS. 6 c and 6 d ).", "Large-scale AFM images showed a smooth, high quality surface with microroughness below 5 nm and absence of microscopic bumps originating from external contaminations.", "However, this smooth surface morphology at high magnification represented a common AFM artifact associated with tip dilation of the lateral dimensions of nanoscale objects.", "[47] Misleading AFM images of “complete”", "monolayers should be treated with great care.", "This effect is demonstrated in FIGS. 6 e and 6 f , displaying two high-resolution AFM images of the gold nanoparticles obtained with an ordinary silicon tip and a carbon nanotube tip.", "The dilation effect was much smaller (but still present) on the AFM image obtained with the nanotube tip that allowed evaluation of nanoparticle concentration for the highest surface coverage.", "This corresponded to the surface coverage of 22% and the average interparticle distance of 26 nm or 2:1 distance-diameter ratio.", "This distance falls in the range where effective collective SPR between neighboring nanoparticles is expected.", "Achieving higher surface concentration under these conditions was prevented by repulsive interactions among nanoparticles.", "This value was relatively high considering that maximum achievable surface coverage that produces 1:1 distance:diameter ratio for different symmetries of particles is within 75-91% and the percolation limit for spherical particles is close to 55%.", "[48] These parameters can only be reached for lightly charged nanoparticles.", "[4] [0084] FIG. 7 shows the UV-visible extinction spectra of gold nanoparticle monolayers with different surface coverages.", "Unlike the spectrum for solution in FIG. 5 , two broad peaks were observed in the region of 500 to 700 nm.", "These peaks could be clearly separated after background subtraction and fitting with Lorentzian functions as demonstrated for one spectrum in FIG. 7 .", "The strong and sharp extinction peak, which appeared around 518±0.5 nm with the width of 53 nm, was virtually unchanged for all monolayers and was caused by the plasmon resonance of isolated gold nanoparticles similarly to dilute solutions.", "The height of this peak showed almost linear increase with the increase of the surface density.", "[0085] Another broad peak appeared around 615 nm at low surface concentration and was red-shifted to 635 nm for the highest surface coverage ( FIG. 7 ).", "The appearance of this second peak is associated with interparticle resonances, which strongly depend upon the distance:diameter ratio among other factors.", "[28,14,49,50] The absorption at this wavelength was very minor for low surface coverage when the distance:diameter ratio was relatively high (4:1 to 7:1) and increased dramatically for the higher surface coverage.", "It became predominant (integral intensity is 200 higher for the second peak than the first peak) for the 22% surface coverage when the distance:diameter ratio decreased to 2:1.", "In fact, such a shape was predicted for a pair of nanoparticles when the distance:diameter ratio falls below 2:1 but it is not usually observed because of low surface coverage achieved experimentally.", "[17,50] A dominance of collective plasmon resonance was observed for monolayers with the distance:diameter ratio below 3:1 ( FIG. 7 ).", "[0086] Because of insufficient surface coverage and non-uniformity of interparticle distance distribution in a vast majority of experiments, only a gradual red-shifting of a broad peak is usually observed without separation of collective and individual resonances.", "[17] In contrast, this broad peak was not originated from the red shift of the individual particle plasmon peak but had a composite nature and contained both individual and collective plasmon resonances.", "[50,51 ] Collective surface plasmon band depends strongly on interparticle separation and, thus, is sensitive to the chemical environment of the particle and its interaction with surroundings.", "[36,50,52] As shown below, nanoparticle-containing multilayers with sufficiently small interparticle distance produced a strong appearance of the distinctive collective resonance peak, which was sensitive to changing the inter-particle distance of gold nanoparticles within intra- and inter layered structures.", "[0087] Gold Nanoparticles-Polymer Multilayer Films.", "The fabrication of the multilayered films began with the deposition of a first polymer bilayer on top of the gold nanoparticle monolayer ( FIG. 4 ).", "FIG. 8 shows the AFM images of a gold nanoparticle array with PAH-PSS bilayer spin-assembled on top.", "A large-scale AFM image (10×10 μm) showed uniformity of this film with overall microroughness not exceeding 2.5 nm.", "Higher-resolution AFM image of the same layer, Au/(PAH-PSS)PAH, showed surface coverage similar to that measured before spin-assembly of top polymer layers.", "This indicated that the gold nanoparticles were strongly attached to the surface of the PEI monolayer and were not dissolved or washed away during the spin-coating and spin-rinsing.", "[0088] The surface of the Au/(PAH-PSS)PAH film was relatively rough due to incomplete surface coverage with gold nanoparticles as indicated by significant surface microroughness.", "As can be seen from the line scan across the scratched film, the gold nanoparticle were covered by PAH-PSS bilayer resulting in a total thickness of nanoparticles aggregates of about 15 nm (the diameter of 12.7 nm+2.3 nm of PAH-PSS bilayer) ( FIG. 8 ).", "The PAH-PSS bilayer thickness of 2.7 nm was independently obtained from the film areas without gold nanoparticles.", "The surface microroughness decreased with an additional deposition of the polymer bilayers.", "Indeed, for the sample Au/(PAH-PSS) 10 PAH, where 10 bilayer were deposited, the multilayer film was very smooth with the microroughness well below 2 nm.", "[0089] UV-visible spectra of Au/(PAH-PSS) n PAH multilayers measured for 5% surface coverage of gold nanoparticles revealed virtually constant intensity of the red-shifted first peak appearing around 535 nm with exact positions of 532±0.5, 536±0.5 and 538±0.5 nm for Au/(PAH-PSS) n PAH with n equal to 1, 3 and 5, respectively ( FIG. 9 ).", "These peaks were 13 to 20 nm red-shifted compared to gold nanoparticle solution (519 nm).", "This red-shift was usually observed for the gold nanoparticles coated with a polymer layer or dissolved in different solvents and is caused by changing dielectric environment.", "[53,54] For a matrix with a large refractive index, the position of the surface plasmon band would shift to longer wavelength.", "[30] With increasing the bilayer number, thicker films covering the gold nanoparticle resulted in the further red-shift of the adsorption peak.", "It should be noted that the second peak for Au/(PAH-PSS) n PAH multilayers changed similarly ( FIG. 9 ).", "With a larger number of polymer layers deposited on the gold nanoparticles, the intensity increased and the peak was further red-shifted.", "This can also be explained by the changing interparticle interaction because of the added dielectric layers.", "However, collective resonance was much more sensitive to the environment composition because red-shifting was more pronounced with the position changing from 630 nm to 720 nm ( FIG. 9 ).", "Finally, a strong absorption peak appearing around 225 nm was caused by the contribution from the PSS chains and was used here for independent control of polymer layer deposition.", "[37] The linear increase of that peak with the number of deposited layers was another strong evidence of the multilayer fabrication despite sparse arrangement of the gold nanoparticles.", "[0090] As a next step, multilayered films were made containing two and three gold layers designed as presented in FIG. 4 .", "Both large-scale and higher-resolution AFM topography images of [Au/(PAH-PSS) 5 PAH] 2 films with a high density of gold nanoparticles possessed microroughness of 4 nm within 1×1 μm surface areas and a film thickness of 40 nm.", "The thickness of the multilayered films [Au/(PAH-PSS) n PAH] m changed linearly with the number of polymer bilayers for different combinations of gold nanoparticles and polymer layers for larger n ( FIG. 10 ).", "Deviations from linear behavior observed for a small number of bilayers can be explained by partially filling the polyelectrolyte into the empty space between the gold nanoparticles.", "The linear increase is a strong evidence of the formation of the multilayered structure in the films.", "The slope of the thickness dependence upon a number of polymer bilayers gives the average PAH-PSS bilayer thickness of 3.2 nm in the [Au/(PAH-PSS) n PAH] 2 film for larger n. This value is close to the estimated thickness of the first bilayer (2.7 nm as discussed above) and corresponds to the results of ellipsometry measurement of (PAH-PSS) n multilayers, which were spin-assembled without gold nanoparticles.", "[25] [0091] UV-visible spectrum of the gold nanoparticle-polymer films with high density of gold nanoparticles (22% surface coverage) is shown in FIG. 11 .", "Three clear peaks can be obviously observed for [Au/(PAH-PSS) n PAH] 2 film.", "The peak at 225 nm showed a linear increase of the PSS material with increasing number of deposited bilayers ( FIG. 11 b ).", "The intensity of strong plasmon resonance of individual nanoparticles at 540 nm was twice that for [Au/(PAH-PSS) n PAH] films with a single gold nanoparticle layer, which indicates good reproducibility in the deposition of the second gold-containing layer.", "The strong collective resonance peak appeared at 640 nm.", "This peak was also observed for gold nanoparticle monolayers and was associated with interparticle interactions within the layer (intralayer resonance).", "One can expect that an additional contribution associated with additional interactions between the gold nanoparticles located in adjacent layers (interlayer resonance) can be detected for some multilayer combinations.", "Such separate contribution are not experimentally observed for such small nanoparticles due, probably, to the masking by very strong intralayer resonance.", "Thus, a series of multilayers was fabricated with increasing number of polymer bilayers between gold intralayers to assure different intra- and inter-layer spacings that can be instructive in separation of inter- and intra-layer resonance contributions.", "[0092] The UV spectra of the [Au/(PAH-PSS) n PAH] 2 multilayers with two layers containing 22% gold nanoparticle separated by the polymer interlayer with different thicknesses (n varied from 1 to 4 that corresponds to the thickness changing from 6.6 nm to 27 nm) showed two clear major peaks with a significant long-wavelength contribution around 800 nm appeared during fitting analysis ( FIG. 12 ).", "Similar results were obtained for films containing three gold nanoparticle layers [Au/(PAH-PSS) n PAH] 3 .", "A plasmon band of isolated gold nanoparticles in these films was further red-shifted due to the presence of additional polymer layers and appeared around 548 nm.", "The collective plasmon resonance peak appeared in the range of 630-640 nm, as was observed before.", "This peak is very broad with long-lasting right shoulder ( FIG. 12 ).", "[0093] Similar spectra were observed for the [Au/(PAH-PSS) n PAH] 2 film with lower concentration of gold nanoparticles ( FIG. 13 ).", "For the film with a single polymer layer between the two gold nanolayers (n=0), we observed a very strong plasmon peak at 656 nm with its intensity 8 times higher than the intensity of individual plasmon resonance.", "Increasing a separation between gold-containing nanolayers caused decreasing intensity and a blue-shift of this peak ( FIG. 13 ).", "The position of this maximum and its intensity became similar to that observed for the gold nanoparticle monolayer only when distance between layers increased above distance:diameter ratio of 2:1.", "[0094] To clarify this behavior and verify the nature of observed long-wave resonance, several new [Au/(PAH-PSS) n PAH] 2 films with gold layers separated by three polymer layers (about 7 nm thick) were prepared by using solutions with different concentrations of gold nanoparticles ( FIG. 14 ).", "Indeed, only an individual plasmon peak was observed for the multilayers with an average intra-layer distance:diameter ratio between 4:1 and 7:1.", "Obviously the very low overall concentration of gold nanoparticles was not sufficient to generate any collective resonances.", "For multilayers with a higher concentration of gold nanoparticles (distance:diameter ratio of 3:1 and lower), an additional contribution in the range of 600-660 nm showed up with a clearly separated second, red-shifted peak appearing for gold nanoparticle content of 15% and higher (distance:diameter ratio of 2.5:1 and 2:1) ( FIG. 14 ).", "Optical data obtained for selected [Au/(PAH-PSS) n PAH] 3 films followed general trends described above.", "[0095] However, what is more important is the-clear appearance of a long-wavelength contribution for higher concentration of gold nanoparticles, which showed up as a wide peak at 780-790 nm similarly to that appeared on the fitting result in FIG. 12 ( FIGS. 12-14 ).", "The maximum contribution of this additional peak (reaching up to 40% of integral intensity) revealed for the multilayered film with two polymer bilayers between gold layers.", "This contribution decreased for both smaller and larger separations of gold layers to below 20% of integral intensity suggesting that the optimized interlayer distance of about 6 nm is required to enhance the appearance of interlayer resonance for the films studied here.", "These changes (intensity and maximum position) directly related to the variation of the interlayer spacing while the intralayer spacing remains unchanged directly suggest the presence of a strong contribution from interparticle resonances between gold nanolayers in addition to intralayer resonance discussed above.", "This phenomenon confirms the suggestion made above on the presence of the independent contribution originating from collective resonance between gold nanoparticles, which belong to different interlayers in the multilayer films (interlayer collective resonances) in addition to usually observed intralayer collective resonances.", "[0096] Film microstructure and optical properties.", "The results on optical properties presented above can be understood considering the real microstructure of gold multilayers derived from AFM data.", "The sketch of [Au/(PAH-PSS) n PAH] 2 film with the distance:diameter ratio of 2:1 is presented in FIG. 15 .", "The formation of bi-layered gold films with incomplete surface coverage and a small number of polymer bilayers in-between inevitably goes through a stage of “filling”", "of the “empty”", "space available within the first deposited gold nanoparticle monolayer.", "In this case, the polymer layers form shells around gold nanoparticles with the thickness controlled by a number of bilayers in the manner presented in FIG. 15 .", "Estimated total thickness of the two layer gold nanoparticle film with three polymer layers between them and parameters obtained from experimental data is about 32 nm, which is fairly close to the experimental result of 38 nm ( FIG. 10 ).", "[0097] For this microstructure, distance:diameter ratio is determined by equation 1+nL/D where L is the thickness of a polymer layer and D is the diameter of gold nanoparticles.", "Considering that, for a small number of layers, the thickness of the individual polymer layer is about 1.4 nm, we can estimate distance:diameter ratio for this microstructure to be close to 1.3:1.", "For this ratio, a strong collective resonance contribution in the range of 800 nm was both predicted theoretically and observed experimentally for metal nanoparticles with larger diameters.", "[28,55] In thicker films, gradual increase of the separation between gold-containing layers causes an increasing distance:diameter ratio to values close to intralayer values and, thus, gradual disappearance of this contribution for thicker films.", "It is obvious that achieving higher nanoparticle density and reaching its theoretical percolation limit of 55% for 2D systems of short-range ordered spherical objects [56,57] should result in a much stronger interlayer collective resonance contribution and clear separation of intralayer and interlayer contributions that is a subject of current investigation.", "Such a phenomenon, if achieved, can be critical for opto-mechanical sensing applications of gold-containing multilayer films that rely on the detection of changes of local intralayer and interlayer microstructures.", "[0098] In accord with the present invention, organized multilayer films from inert metal nanoparticles and polyelectrolyte multilayers have been fabricated very time efficiently with LbL and spin-assisted LbL assembly techniques.", "SA-LbL films [Au/(PAH-PSS) n PAH] m with different designs possessed well organized microstructure with uniform surface morphology and high optical quality.", "[0099] The present invention thus provides compliant, highly-uniform, robust, smooth, and long-living free standing LbL films with record high mechanical parameters.", "These are true nanoscale films with an overall thickness ranging from 20 to 70 nm for films with a different number of layers.", "These free-standing films can be manufactured very time-efficiently with SA LbL assembly with an exceptionally high level of uniformity and integrity.", "These properties facilitate their ability to sustain multiple elastic deformations unachievable for the multilayered films fabricated with conventional LbL techniques.", "These unexpected properties are believed to be due to different conformation of the macromolecules adsorbed under the conditions of the shear stresses and adapting a much more spread state allowing for more uniform in-plane coverage of the stratified interfaces.", "The parameters achieved here for these nanoscale free-standing films (the elastic modulus of 30-40 GPa, the ultimate strain of 2%, and the ultimate tensile strength of 130 MPa) surpass those known for much thicker nanoparticle-containing free standing LbL films reported to date and possess a life time of millions of deformational cycles.", "[0100] All SA-LbL films showed the strong extinction peak in the range of 510-550 nm, which is due to the plasmon resonance of the individual gold nanoparticles red-shifted because of a local dielectric environment.", "For films with sufficient gold nanoparticle density within the layers (10-22%), the second strong peak was consistently observed between 620-660 nm, which is due to the collective plasmon resonance from intralayer interparticle coupling.", "Finally, under certain conditions, interlayer interparticle resonance can be separated as an additional, independent contribution around 800 nm in UV-visible spectra.", "This observation was obtained for multilayer films with a conventional level of the dense surface coverage (that is within 10-20% surface coverage).", "[58] The independent and concurrent detection of all individual, intralayer, and interlayer plasmon resonances for carefully designed multilayered films with higher content of gold nanoparticles achievable with LbL assembly can be critical for sensing applications which involve monitoring of opto-mechanical properties of these optically active films.", "The present invention thus provides a first example of robust, high-sensitive, free-suspended film of this type.", "EXAMPLE 2—REFERENCES [0000] [4] .", "Fendler, J. 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Adv.", "Mater.", ", 1997, 9, 61.", "[0137] All publications, patents and patent applications are incorporated herein by reference.", "While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for purposes of illustration it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein may be varied considerably without departing from the basic principles of the invention." ]
CROSS REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of the Provisional Application Ser. No. 60/442,498 filed on Jan. 24, 2003, and is a continuation in part of U.S. application Ser. No. 10/342,422, filed on Jan. 13, 2003, which claims the benefit of U.S. Provisional Application No. 60/347,763, filed on Jan. 11, 2002. FIELD OF THE INVENTION [0002] The present invention relates to a method and apparatus for controlling the flow of a fluid within a piping apparatus, and more particularly to a piping apparatus that controls the flow of a fluid for backwashing a filter. BACKGROUND OF THE INVENTION [0003] In the past, fluid from cooling towers was directly discharged without the benefit of treatment or recycling for reuse the cooling tower. However, since the 1970's, such discharge has been subject to EPA pre-treatment standards and NPDES effluent limitations, as well as local regulations. Additionally, such “once through” fluid usage leads to high fluid and sewerage cost. [0004] In response to regulatory restrictions and fluid cost, fluid filtration devices have been developed to treat cooling tower discharge for recycling back to the cooling tower. It is important that the fluid quality from such treatment devices be sufficient to prevent scaling, erosion, and biological fouling in the cooling tower. Of particular importance is the removal efficiency of suspended solids. The concentration of suspended solids in cooling tower inlet fluid affects the number of times that the fluid can be recycled before solids precipitate from solution. Clearly, fluid with high initial suspended solids can be recycled only a minimal number of times before precipitation occurs in comparison to more purified fluid. [0005] A common treatment device that provides full flow filtration of process fluid from a cooling tower is a sand bed filters. During normal operation, fluid flows into the filter inlet at and through the pumping apparatus to the inlet on the top of the tank. The fluid is then sprayed out over a bed of filter media, that can be sand or other media known in the art. The fluid then percolates down through the filter media to the exit piping. There, it flows to the filter outlet, where it is pumped for reuse in the cooling tower or other application. [0006] Due to large quantities of dissolved solids and other contaminants in the fluid that accrue in the filter media during the normal operation cycle, there are a finite number of circulations that can be made by the fluid. When solid and contaminant concentration increases, the pressure at which the pump must operate increases. Also, the amount of throughput in the filter decreases. When this reaches a predefined critical level, a backwash cycle is signaled. [0007] During the backwash cycle, fluid is not pumped through the filter media in the normal downward direction. Instead, the effluent is pumped up through the bottom of the filter media, entering the filtration tank from what is the “exit piping” in normal operation. The fluid is pumped back up through the filter media at a rate slow enough that it will not cause undue disturbance therein, and result in the unwanted disposal of the filter media. However, the upward action of the fluid is sufficient to remove any trapped solids and contaminants from the filter media. When the backwash reaches the “entrance hole, it is pumped out, and directed a waste valve that purges the backwash fluid from the system. [0008] Depending on the availability of a fluid supply from the external, it is sometimes advantageous to backwash the filter media with external fluid or process fluid. Interchange from one fluid source to another usually requires extensive retooling of the pumping apparatus, and downtime for the cooling tower. [0009] For example, if external fluid becomes available after operation of the treatment filter, it is often desirable to convert the piping apparatus in order to utilize the external fluid for backwashing. Backwashing with external fluid is advantageous since it is clear or suspended solids. In contrast, by backwashing with processed fluid from the cooling tower, suspended solids within the process fluid are introduced into the filter media during backwashing. As such, some of the solids may become impregnated into the filter media. Another example, that is typical of filtration device startup, the initial process fluid contains a very high amount of solids. This concentration of solids within the process fluid decreases after the cooling tower has been used for a while. As such, it would be desirable to utilize external fluid for backwashing during the break-in period for the cooling tower, and then utilize process fluid from the cooling tower for backwashing once the cooling tower break-in period is completed. Such ability to switch between external fluid and cooling tower process fluid for backwashing allows for the clean external fluid to be used when the process fluid contains the highest amounts of solids, and for the process fluid, once cleaner, to be used in order to save on the cost of fluid usage. [0010] What is needed is for a piping apparatus that is adapted for use with a filtration device, wherein the piping apparatus easily allows external fluid or process fluid to be interchangeably used for backwashing the filtration device. DESCRIPTION OF THE PRIOR ART [0011] Applicant is aware of the following U.S. patent concerning an apparatus using a filter media for treating fluid: U.S. Pat. No. Issue Date Inventor Title  4,141,824 Feb. 27, 1979 Smith Tangentially fed upflow sand filter method and apparatus U.S. App Jan. 13, 2002 Morgan et al. Tangentially Fed 10/342,422 Meida Filter and Apparatus [0012] Smith, U.S. Pat. No. 4,141,824, discloses an apparatus for purifying fluid by filtration in which fluid is passed upwardly through one or more sand beds supported in a tower, at a slow rate so that the sand bed in not disturbed. Fluid feed to each tower is accomplished by tangentic flow from an inlet. Backwash of the sand bed is accomplished by opening a duct valve at the coned lower end which forms the base of the tower in which the sand bed is supported. Bacterial activity in the lower part of the sand bed is controlled to enhance purification of the fluid. Additionally, chemical treatment of the fluid may be used in conjunction with filtration to further treat the fluid. [0013] Morgan et al., U.S. application Ser. No. 10/342,422, discloses a fluid treatment device for purifying process fluid by filtration wherein process fluid is tangentially introduced and caused to swirl in the housing above a filter media, before passing downwards through silica and gravel beds. The swirling increases the through capacity of the treatment device and reduces the amount of particles that would otherwise become imbedded in the filter media. Backwashing is accomplished by forcing fluid, through first and second components of the fluidizer, into the filter media. The first component is a channel formed in the manifold which provides backwash fluid to the bottom of the gravel bed. The second component provides backwash fluid at the gravel bed—silica bed interface by a series of radially spaced fluidizer arms. The fluidizer manifold provides complete fluidization of the filter media such that the filter media does not have no flow, or low flow, areas. SUMMARY OF THE INVENTION [0014] The present invention is a piping apparatus that is adapted for use with a filtration device, wherein the piping apparatus easily allows source or process fluids to be interchangeably used for reversing the flow in a filtration device. It will enable easy conversion from one source of flow to another either by a slight piping modification or as an individual unit with dual source modes integral to the system. This invention can be integral to or separate from the filtration system. OBJECTS OF THE INVENTION [0015] The principal object of the invention is to provide an improved method for facilitating the backwash of a fluid treatment facility. [0016] The another object of the invention is to provide an improved method for facilitating the backwash of a fluid treatment facility, whereby the backwash effluent can be easily alternated between a external fluid source and a process fluid source. [0017] Another object of the invention is to provide an improved piping apparatus that facilitates the easy switching from a external fluid backwash source to a process fluid backwash source. [0018] Another object of the invention is to provide a fluid treatment device utilizing this improved piping apparatus for removing suspended solids from process fluid. [0019] A further object of the present invention is to provide a fluid treatment device utilizing this improved piping apparatus that efficiency removes suspended solids, including those of small diameter. [0020] Another object of the invention is to within one system provide the capability to use either an external or source fluid for backwash in a single system. A result of this is that the system can move from one source to another source of backwash fluid by either manually moving a valve or by repositioning a switch on the control panel. [0021] A further object within this arrangement is to be able, by using any number of monitoring devices (such as a conductivity meter), to have the control system automatically select the source of backwash fluid. BRIEF DESCRIPTION OF THE DRAWINGS [0022] The foregoing and other objects will be become more readily apparent by referring to the following detailed description and the appended drawings in which: [0023] [0023]FIG. 1 is a front view of the invented fluid treatment device and piping assembly; [0024] [0024]FIG. 2 is a side view of the fluid treatment device and piping assembly of FIG. 1; [0025] [0025]FIG. 3 is a simplified schematic of the piping assembly of FIGS. 1 and 2, depicting the liquid media flow during normal operation of the fluid treatment device and piping assembly. [0026] [0026]FIG. 4 is a simplified schematic of the piping assembly of FIGS. 1 and 2, depicting the liquid media flow through the fluid treatment device and piping assembly in a process fluid backwash configuration. [0027] [0027]FIG. 5 is a simplified schematic of the piping assembly of FIGS. 1 and 2, depicting the liquid media flow through the fluid treatment device and piping assembly in an external fluid backwash configuration. DETAILED DESCRIPTION [0028] The present invention is a filtration treatment device having a filter media for purifying a fluid. Not to be construed as limiting, the treatment device is typically employed to treat process fluid from a cooling tower for reuse by the cooling tower. The filter media effectively removes suspended solids from the process fluid. Periodically, the filter media is backwashed in order to remove captured solids therefrom. The device is configured to provide superior solids removal during backwashing thereby increasing the effective life of the filter media. [0029] Referring now to the drawings, and particularly to FIGS. 1 and 2, a fluid treatment device 10 is shown comprising a filter media 12 contained within a housing 14 . Process fluid, from a source such as, for example, a cooling tower, is passed downwardly through the media 12 in order to filter organic and inorganic matter from the process fluid. [0030] A piping assembly 16 handles the process fluid for delivery to the treatment device 10 , the treatment device effluent for returning to the cooling tower, or to some other location, and backwash fluid, when backwashing is being performed. Specifically, the piping assembly 16 includes a first manifold 20 and second manifold 21 and an actuator 23 having a plurality of three way valves to control flow into the following conduits: a process fluid conduit 22 for conveying process fluid from the source, an inlet conduit 24 for delivering process fluid to the device 10 for treatment, an outlet conduit 26 for carrying effluent from the treatment device 10 and for conveying backwash, a return conduit 28 for returning effluent for reuse by the source, and a waste conduit 30 (FIG. 2) for conveying backwash to a settling pond or other location for further treatment. For simplicity, components that are nonessential to the present invention such as extraneous valves, pumps, pressure gauges, and the like, are omitted from description as these elements are conventional and may be provided as necessary by the skilled practitioner in the art. Flow meters may also be provided as desired or required for proper operation of the treatment device 10 . [0031] An external conduit 27 is provided in the piping assembly 16 , such that one can select the source of backwash fluid with which to flood the filter device. The external conduit 27 is integrally connected to the second manifold piping assembly 21 such that the selected external fluid backwash or process fluid backwash is directed through the outlet conduit 26 and into the treatment device 10 . [0032] The treatment device 10 floods with backwash fluid until the effluent level therein rises to the level of the inlet conduit 24 . The effluent then flows out of the treatment device 10 through the inlet conduit 24 . The backwashed effluent is then directed to the waste conduit 30 , where it exits the piping assembly 16 to a holding tank, treatment pond, or the like. [0033] The housing 14 defines a chamber having a cylindrical intermediate portion 42 , a top portion 44 and a conical bottom portion 46 , which are respectively defend by a circular side wall 48 , a concave top wall 50 that closes the top of the housing 14 , and a conical lower wall 52 that forms the bottom of the housing 14 . These housing 14 portions are joined by conventional welding to hold the filter media 12 . The housing 14 is supported on a suitable foundation, not shown, by a plurality of spaced columns 55 , in conventional manner. Suitable cross braces, not shown, for the columns 55 may also be provided. [0034] The intermediate portion 42 of the housing 14 may be of any suitable diameter, but in most applications the diameter will be between 2 feet and 3 feet. The housing 14 may also be of any suitable height, but typical will be between 5 feet and 7 feet so that the filter media 12 can be of sufficient depth. The depth of the filter media 12 , for a given application, is determined by known engineering methods taking into account the degree of process fluid purification desired and the point of decreasing returns where excessive pumping pressures are encountered without great benefaction to fluid purity. [0035] A loading port 58 is provided in the top of the housing 14 for loading filter media 12 . Also provided in the top portion 44 of the housing 14 is an air release valve 60 for preventing inadvertent rupture of the housing 14 due to pressure changes during operation and backwashing. A cleanout port, not shown, is provided in the lower end of the housing 14 for filter media 12 removal under atypical scenarios wherein the filter media 12 has become contaminated or impacted. [0036] The inlet conduit 24 is sealedly fixed through the circular side wall 48 , preferably by welding, so that the process fluid conveyed there-through is introduced, preferably tangentially, into the housing 14 above the filter media 12 . If tangential communication between the inlet conduit 24 and circular side wall 48 the fluid is caused to circularly swirl along the top of the filter media 12 . There is sufficient freeboard between the inlet conduit 24 and the filter media 12 to accommodate swirling. [0037] The filter media 12 comprises a gravel bed (not shown) which substantially fills the hemispherical bottom portion 46 of the housing 14 to a height above that of the exit conduit. A silica bed (not shown) which is supported by the gravel bed partially fills the intermediate portion 42 of the housing 14 . Although different gravel and silica may be used, pea gravel sized ⅛ inch to ¼ inch is suitable, and the silica is preferably spherical with about a 0.35 mm diameter, or optionally, may have an irregular shape. The filter media 12 is preferably configured to remove particles that are at least 0.45 microns in size from process fluid as it passes downwardly there-through. Conventional engineering methods are used to properly select the size and packing density of the gravel and silica and, accordingly, to select the desired filter media removal efficiency. [0038] Normal flow of the process fluid through the piping apparatus is shown in FIG. 3. Fluid from the cooling tower or other application enters the piping apparatus 16 through the process fluid conduit 22 . The process fluid then flows into the first manifold 20 , where it is directed into the housing 14 of the treatment device 10 via the inlet conduit 24 . The process fluid then percolates down through the filter media 12 contained by the treatment device 10 . The now filtered fluid flows out of the housing 14 through the outlet conduit 26 . The filtered fluid is then directed through the second manifold 21 and out of the piping assembly 16 through the return conduit 28 , for reuse in the cooling tower or other application. [0039] By introducing the process fluid tangentially into the treatment device 10 , the fluid is caused to swirl above the silica bed. The swirling assists in preventing channeling through the filter media 12 . Moreover, the velocity of the swirling fluid is greater near the peripheral than the center, disturbing the silica bed to become slightly coned shaped. The cone shape increases the effective surface area of the silica bed and, hence, its capacity to treat fluid. Overall, the swirling, in conjunction with the coned silica bed, enables the filter bed to operate at an increased flow rate of approximately 25 to 30 percent. The device 10 can be configured to treat various flow rates. Notwithstanding, it is expected that a common treatment capacity of the present invention will be about 25-30 gals/min/ft 2 . [0040] Swirling the process fluid is also advantageous in that it imparts a centripetal force component to the flow whereby suspended solids are forced outwardly to the circular sidewall 48 where a percentage of the suspended solids are kept in suspension. By temporarily or permanently keeping solids in suspension, fewer particles become deeply embedded in the filter media 12 or in the interstitial spacing of the media 12 . Accordingly, upon backwashing, suspended solids quickly separate from the filter media 12 . Since particles are more efficiently removed from the filter media 12 , significantly less backwash fluid, in the range of about 50-60 percent, is required than with conventional filters of similar treatment capacity. This efficiency difference exists because traditional filters linearly introduce fluid through a filter media 12 which drives the particles deeply into the media 12 where they become impacted. Consequently, greater backwash flow is required to remove particles from the interstitial spaces deep within the filter media 12 . [0041] Initially, process fluid is tangentially fed into the treatment device 10 through the inlet conduit 24 to impart a swirling motion to the process fluid above the upper surface of the silica bed. The swirling fluid causes the silica bed to become coned, increasing the silica bed's effective surface area. Since the surface area is enlarged, the rate in which the silica bed can treat the process fluid is increased. [0042] Additionally, by causing the process fluid to swirl, a percentage of the suspended solids is maintained in suspension above the silica bed while the process fluid passes downward through the filter media 12 where the remaining solids are stripped out from the process fluid. Hence, swirling the process fluid reduces particulate matter loading to the filter media 12 , and reduces the amount of particles that would have become deeply imbedded or impacted in the filter media 12 . Upon passing through the filter media 12 , the purified fluid egresses the housing 14 through outlet conduit 26 disposed at the bottom of the housing 14 . The cleansed effluent is returned to the cooling tower for reuse. [0043] In order to effectuate backwashing, flow is reversed through the treatment device 10 so that process fluid, external fluid, or collected effluent, flows into the device 10 through the outlet conduit 26 , is forced upwardly through the filter media 12 , then exits the housing 14 through the inlet conduit 24 for proper disposal. As an example, for the device 10 to treat 25 - 30 gals/min/ft 2 , backwash fluid is introduced into the filter media 12 at a preferred rate of about 25 gal/min/ft 2 to fully fluidized the filter media 12 and to carry particles having a specific gravity that is less than that of gravel and silica from the housing 14 . The freeboard within the housing 14 between the upper surface of the silica bed and the inlet conduit 24 is sufficient to enable settling of any silica which may be carried up by the rising backwash fluid. The frequency of backwashing can be controlled by a pressure switch, timer or manually actuated. When using a pressure switch, the preferred pressure drop is approximately 5-12 pounds/inch 2 . [0044] As backwash fluid is passed upwardly through the filter media 12 , particles with a lower specific gravity than that of gravel or silica are carried through the filter media 12 and egress the housing 14 via the inlet conduit 24 for proper disposal. There is sufficient freeboard between the silica bed and the inlet conduit 24 to allow silica, which have become entrained in the backwash, to settle back to the silica bed. [0045] Complete fluidization of the filter media 12 during backwash is preferred in order to thoroughly clean the media 12 of imbedded particles, re-stratify the filter media 12 and to break any bonding of the media 12 (for example, calcification from hard fluid). If the filter media 12 is not completely fluidized during backwashing, the filter media 12 may see no flow or minimal flow conditions. At these low flow areas, captured particles are not removed and the media 12 is not fully re-stratified. No flow conditions combined with non-removed foreign particles are detrimental since they provide a breeding ground for bacteria. Furthermore, an unfluidized filter media 12 becomes compacted, reducing the treatment capacity of the treatment device, and thus requiring replacement. [0046] Complete fluidization of the filter media 12 includes the steps of lifting the entire filter media 12 from its fully packed condition and allowing it to expand at least 30 percent. This allows gravel, silica and captured particle to break free from neighboring matter. [0047] Under typical loading conditions, the backwashing method of the present invention is so effective at removing particulate matter that significant bacteria growth does not occur in the filter media 12 . Additionally, a flocking agent is not typically required since the treatment device 10 removes suspended solids at such a high efficiency. Notwithstanding the superior performance of the treatment device 10 , under certain situation it may be desirable to provide chlorine or bromine for bacteria treatment, or a flocking agent, such as alum. As such, known automated or manual devices can be added to the fluid treatment device 10 . [0048] When utilizing process fluid backwash as exemplified in FIG. 4, the process fluid flows in through the process fluid conduit 22 . Through the use of a series of actuators 23 , the fluid flow is directed across a check valve 36 . In normal operation, the check valve 36 remains in a closed position, with the process fluid not exerting enough pressure upon it to cause the valve to open. However, when utilizing external fluid in the backwash configuration, the process fluid is physically blocked from its normal course of flow from the process fluid conduit 20 into the inlet conduit 24 . The pressure inside the piping assembly 16 increases as more process fluid is forced in therein. This pressure increase causes the check valve 36 (not shown) to open. The process fluid can then flow from the process conduit 20 into the outlet conduit 26 , and enter the treatment device 10 from the reverse direction. Note that the return conduit 28 has also been blocked in this configuration, by a corresponding actuator movement to that described previously. The process fluid flows from the second manifold 21 into the outlet conduit 26 where it enters the treatment device 10 . The treatment device 10 then floods until the effluent level therein rises to the level of the inlet conduit 24 . The effluent then flows out of the treatment device 10 through the inlet conduit 24 . The backwashed effluent is then directed to the waste conduit 30 , where it exits the piping assembly 16 to a holding tank, treatment pond, or the like. [0049] As shown in FIG. 5, when utilizing the external fluid for the backwash media, external fluid is allowed to enter the piping apparatus 16 from the external conduit 27 where it is then directed into the manifold 20 . The one-way check valve 36 (not shown) prevents the external fluid from flowing back through the process fluid conduit 22 , and into the cooling tower. The external fluid flows from the second manifold 21 where it is directed by the actuator 23 (not shown) into the outlet conduit 26 where it enters the treatment device 10 . The treatment device 10 then floods until the effluent level therein rises to the level of the inlet conduit 24 . The effluent then flows out of the treatment device 10 through the inlet conduit 24 . The backwashed effluent is then directed to the waste conduit 30 , where it exits the piping assembly 16 to a holding tank, treatment pond, or the like. SUMMARY OF THE ACHIEVEMENT OF THE OBJECTS OF THE INVENTION [0050] From the foregoing, it is readily apparent that we have invented a piping apparatus for use with a fluid treatment device having a filter media for purifying process fluid. The piping apparatus allows for easy selection between a plurality of backwash sources, preferably between an internal or process fluid source, and an external or external fluid source. [0051] It is to be understood that the foregoing description and specific embodiments are merely illustrative of the best mode of the invention and the principles thereof, and that various modifications and additions may be made to the apparatus by those skilled in the art, without departing from the spirit and scope of this invention, which is therefore understood to be limited only by the scope of the appended claims.
A piping apparatus for use with a filtration device, the piping apparatus easily allowing a plurality of fluid sources interchangeably used for backwashing the filtration device. The piping apparatus consists of an inlet conduit, an outlet conduit and a process conduit, and at least one additional conduit. In normal operation, process fluid flows into from the process conduit to the inlet conduit, into the filtration device, and out the outlet conduit for reuse in the attached process. Backwashing is accomplished by forcing fluid from either the process conduit or the additional conduit through the outlet conduit into the filtration device and then out of the inlet conduit. A plurality of backwash sources are provided such that an operator can selectably choose between the plurality of backwash fluids. A system of valves and actuators are provided to direct flow into the selected conduits, and to prevent cross-contamination of the backwash sources.
Briefly describe the main invention outlined in the provided context.
[ "CROSS REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of the Provisional Application Ser.", "No. 60/442,498 filed on Jan. 24, 2003, and is a continuation in part of U.S. application Ser.", "No. 10/342,422, filed on Jan. 13, 2003, which claims the benefit of U.S. Provisional Application No. 60/347,763, filed on Jan. 11, 2002.", "FIELD OF THE INVENTION [0002] The present invention relates to a method and apparatus for controlling the flow of a fluid within a piping apparatus, and more particularly to a piping apparatus that controls the flow of a fluid for backwashing a filter.", "BACKGROUND OF THE INVENTION [0003] In the past, fluid from cooling towers was directly discharged without the benefit of treatment or recycling for reuse the cooling tower.", "However, since the 1970's, such discharge has been subject to EPA pre-treatment standards and NPDES effluent limitations, as well as local regulations.", "Additionally, such “once through”", "fluid usage leads to high fluid and sewerage cost.", "[0004] In response to regulatory restrictions and fluid cost, fluid filtration devices have been developed to treat cooling tower discharge for recycling back to the cooling tower.", "It is important that the fluid quality from such treatment devices be sufficient to prevent scaling, erosion, and biological fouling in the cooling tower.", "Of particular importance is the removal efficiency of suspended solids.", "The concentration of suspended solids in cooling tower inlet fluid affects the number of times that the fluid can be recycled before solids precipitate from solution.", "Clearly, fluid with high initial suspended solids can be recycled only a minimal number of times before precipitation occurs in comparison to more purified fluid.", "[0005] A common treatment device that provides full flow filtration of process fluid from a cooling tower is a sand bed filters.", "During normal operation, fluid flows into the filter inlet at and through the pumping apparatus to the inlet on the top of the tank.", "The fluid is then sprayed out over a bed of filter media, that can be sand or other media known in the art.", "The fluid then percolates down through the filter media to the exit piping.", "There, it flows to the filter outlet, where it is pumped for reuse in the cooling tower or other application.", "[0006] Due to large quantities of dissolved solids and other contaminants in the fluid that accrue in the filter media during the normal operation cycle, there are a finite number of circulations that can be made by the fluid.", "When solid and contaminant concentration increases, the pressure at which the pump must operate increases.", "Also, the amount of throughput in the filter decreases.", "When this reaches a predefined critical level, a backwash cycle is signaled.", "[0007] During the backwash cycle, fluid is not pumped through the filter media in the normal downward direction.", "Instead, the effluent is pumped up through the bottom of the filter media, entering the filtration tank from what is the “exit piping”", "in normal operation.", "The fluid is pumped back up through the filter media at a rate slow enough that it will not cause undue disturbance therein, and result in the unwanted disposal of the filter media.", "However, the upward action of the fluid is sufficient to remove any trapped solids and contaminants from the filter media.", "When the backwash reaches the “entrance hole, it is pumped out, and directed a waste valve that purges the backwash fluid from the system.", "[0008] Depending on the availability of a fluid supply from the external, it is sometimes advantageous to backwash the filter media with external fluid or process fluid.", "Interchange from one fluid source to another usually requires extensive retooling of the pumping apparatus, and downtime for the cooling tower.", "[0009] For example, if external fluid becomes available after operation of the treatment filter, it is often desirable to convert the piping apparatus in order to utilize the external fluid for backwashing.", "Backwashing with external fluid is advantageous since it is clear or suspended solids.", "In contrast, by backwashing with processed fluid from the cooling tower, suspended solids within the process fluid are introduced into the filter media during backwashing.", "As such, some of the solids may become impregnated into the filter media.", "Another example, that is typical of filtration device startup, the initial process fluid contains a very high amount of solids.", "This concentration of solids within the process fluid decreases after the cooling tower has been used for a while.", "As such, it would be desirable to utilize external fluid for backwashing during the break-in period for the cooling tower, and then utilize process fluid from the cooling tower for backwashing once the cooling tower break-in period is completed.", "Such ability to switch between external fluid and cooling tower process fluid for backwashing allows for the clean external fluid to be used when the process fluid contains the highest amounts of solids, and for the process fluid, once cleaner, to be used in order to save on the cost of fluid usage.", "[0010] What is needed is for a piping apparatus that is adapted for use with a filtration device, wherein the piping apparatus easily allows external fluid or process fluid to be interchangeably used for backwashing the filtration device.", "DESCRIPTION OF THE PRIOR ART [0011] Applicant is aware of the following U.S. patent concerning an apparatus using a filter media for treating fluid: U.S. Pat. No. Issue Date Inventor Title 4,141,824 Feb. 27, 1979 Smith Tangentially fed upflow sand filter method and apparatus U.S. App Jan. 13, 2002 Morgan et al.", "Tangentially Fed 10/342,422 Meida Filter and Apparatus [0012] Smith, U.S. Pat. No. 4,141,824, discloses an apparatus for purifying fluid by filtration in which fluid is passed upwardly through one or more sand beds supported in a tower, at a slow rate so that the sand bed in not disturbed.", "Fluid feed to each tower is accomplished by tangentic flow from an inlet.", "Backwash of the sand bed is accomplished by opening a duct valve at the coned lower end which forms the base of the tower in which the sand bed is supported.", "Bacterial activity in the lower part of the sand bed is controlled to enhance purification of the fluid.", "Additionally, chemical treatment of the fluid may be used in conjunction with filtration to further treat the fluid.", "[0013] Morgan et al.", ", U.S. application Ser.", "No. 10/342,422, discloses a fluid treatment device for purifying process fluid by filtration wherein process fluid is tangentially introduced and caused to swirl in the housing above a filter media, before passing downwards through silica and gravel beds.", "The swirling increases the through capacity of the treatment device and reduces the amount of particles that would otherwise become imbedded in the filter media.", "Backwashing is accomplished by forcing fluid, through first and second components of the fluidizer, into the filter media.", "The first component is a channel formed in the manifold which provides backwash fluid to the bottom of the gravel bed.", "The second component provides backwash fluid at the gravel bed—silica bed interface by a series of radially spaced fluidizer arms.", "The fluidizer manifold provides complete fluidization of the filter media such that the filter media does not have no flow, or low flow, areas.", "SUMMARY OF THE INVENTION [0014] The present invention is a piping apparatus that is adapted for use with a filtration device, wherein the piping apparatus easily allows source or process fluids to be interchangeably used for reversing the flow in a filtration device.", "It will enable easy conversion from one source of flow to another either by a slight piping modification or as an individual unit with dual source modes integral to the system.", "This invention can be integral to or separate from the filtration system.", "OBJECTS OF THE INVENTION [0015] The principal object of the invention is to provide an improved method for facilitating the backwash of a fluid treatment facility.", "[0016] The another object of the invention is to provide an improved method for facilitating the backwash of a fluid treatment facility, whereby the backwash effluent can be easily alternated between a external fluid source and a process fluid source.", "[0017] Another object of the invention is to provide an improved piping apparatus that facilitates the easy switching from a external fluid backwash source to a process fluid backwash source.", "[0018] Another object of the invention is to provide a fluid treatment device utilizing this improved piping apparatus for removing suspended solids from process fluid.", "[0019] A further object of the present invention is to provide a fluid treatment device utilizing this improved piping apparatus that efficiency removes suspended solids, including those of small diameter.", "[0020] Another object of the invention is to within one system provide the capability to use either an external or source fluid for backwash in a single system.", "A result of this is that the system can move from one source to another source of backwash fluid by either manually moving a valve or by repositioning a switch on the control panel.", "[0021] A further object within this arrangement is to be able, by using any number of monitoring devices (such as a conductivity meter), to have the control system automatically select the source of backwash fluid.", "BRIEF DESCRIPTION OF THE DRAWINGS [0022] The foregoing and other objects will be become more readily apparent by referring to the following detailed description and the appended drawings in which: [0023] [0023 ]FIG. 1 is a front view of the invented fluid treatment device and piping assembly;", "[0024] [0024 ]FIG. 2 is a side view of the fluid treatment device and piping assembly of FIG. 1;", "[0025] [0025 ]FIG. 3 is a simplified schematic of the piping assembly of FIGS. 1 and 2, depicting the liquid media flow during normal operation of the fluid treatment device and piping assembly.", "[0026] [0026 ]FIG. 4 is a simplified schematic of the piping assembly of FIGS. 1 and 2, depicting the liquid media flow through the fluid treatment device and piping assembly in a process fluid backwash configuration.", "[0027] [0027 ]FIG. 5 is a simplified schematic of the piping assembly of FIGS. 1 and 2, depicting the liquid media flow through the fluid treatment device and piping assembly in an external fluid backwash configuration.", "DETAILED DESCRIPTION [0028] The present invention is a filtration treatment device having a filter media for purifying a fluid.", "Not to be construed as limiting, the treatment device is typically employed to treat process fluid from a cooling tower for reuse by the cooling tower.", "The filter media effectively removes suspended solids from the process fluid.", "Periodically, the filter media is backwashed in order to remove captured solids therefrom.", "The device is configured to provide superior solids removal during backwashing thereby increasing the effective life of the filter media.", "[0029] Referring now to the drawings, and particularly to FIGS. 1 and 2, a fluid treatment device 10 is shown comprising a filter media 12 contained within a housing 14 .", "Process fluid, from a source such as, for example, a cooling tower, is passed downwardly through the media 12 in order to filter organic and inorganic matter from the process fluid.", "[0030] A piping assembly 16 handles the process fluid for delivery to the treatment device 10 , the treatment device effluent for returning to the cooling tower, or to some other location, and backwash fluid, when backwashing is being performed.", "Specifically, the piping assembly 16 includes a first manifold 20 and second manifold 21 and an actuator 23 having a plurality of three way valves to control flow into the following conduits: a process fluid conduit 22 for conveying process fluid from the source, an inlet conduit 24 for delivering process fluid to the device 10 for treatment, an outlet conduit 26 for carrying effluent from the treatment device 10 and for conveying backwash, a return conduit 28 for returning effluent for reuse by the source, and a waste conduit 30 (FIG.", "2) for conveying backwash to a settling pond or other location for further treatment.", "For simplicity, components that are nonessential to the present invention such as extraneous valves, pumps, pressure gauges, and the like, are omitted from description as these elements are conventional and may be provided as necessary by the skilled practitioner in the art.", "Flow meters may also be provided as desired or required for proper operation of the treatment device 10 .", "[0031] An external conduit 27 is provided in the piping assembly 16 , such that one can select the source of backwash fluid with which to flood the filter device.", "The external conduit 27 is integrally connected to the second manifold piping assembly 21 such that the selected external fluid backwash or process fluid backwash is directed through the outlet conduit 26 and into the treatment device 10 .", "[0032] The treatment device 10 floods with backwash fluid until the effluent level therein rises to the level of the inlet conduit 24 .", "The effluent then flows out of the treatment device 10 through the inlet conduit 24 .", "The backwashed effluent is then directed to the waste conduit 30 , where it exits the piping assembly 16 to a holding tank, treatment pond, or the like.", "[0033] The housing 14 defines a chamber having a cylindrical intermediate portion 42 , a top portion 44 and a conical bottom portion 46 , which are respectively defend by a circular side wall 48 , a concave top wall 50 that closes the top of the housing 14 , and a conical lower wall 52 that forms the bottom of the housing 14 .", "These housing 14 portions are joined by conventional welding to hold the filter media 12 .", "The housing 14 is supported on a suitable foundation, not shown, by a plurality of spaced columns 55 , in conventional manner.", "Suitable cross braces, not shown, for the columns 55 may also be provided.", "[0034] The intermediate portion 42 of the housing 14 may be of any suitable diameter, but in most applications the diameter will be between 2 feet and 3 feet.", "The housing 14 may also be of any suitable height, but typical will be between 5 feet and 7 feet so that the filter media 12 can be of sufficient depth.", "The depth of the filter media 12 , for a given application, is determined by known engineering methods taking into account the degree of process fluid purification desired and the point of decreasing returns where excessive pumping pressures are encountered without great benefaction to fluid purity.", "[0035] A loading port 58 is provided in the top of the housing 14 for loading filter media 12 .", "Also provided in the top portion 44 of the housing 14 is an air release valve 60 for preventing inadvertent rupture of the housing 14 due to pressure changes during operation and backwashing.", "A cleanout port, not shown, is provided in the lower end of the housing 14 for filter media 12 removal under atypical scenarios wherein the filter media 12 has become contaminated or impacted.", "[0036] The inlet conduit 24 is sealedly fixed through the circular side wall 48 , preferably by welding, so that the process fluid conveyed there-through is introduced, preferably tangentially, into the housing 14 above the filter media 12 .", "If tangential communication between the inlet conduit 24 and circular side wall 48 the fluid is caused to circularly swirl along the top of the filter media 12 .", "There is sufficient freeboard between the inlet conduit 24 and the filter media 12 to accommodate swirling.", "[0037] The filter media 12 comprises a gravel bed (not shown) which substantially fills the hemispherical bottom portion 46 of the housing 14 to a height above that of the exit conduit.", "A silica bed (not shown) which is supported by the gravel bed partially fills the intermediate portion 42 of the housing 14 .", "Although different gravel and silica may be used, pea gravel sized ⅛ inch to ¼ inch is suitable, and the silica is preferably spherical with about a 0.35 mm diameter, or optionally, may have an irregular shape.", "The filter media 12 is preferably configured to remove particles that are at least 0.45 microns in size from process fluid as it passes downwardly there-through.", "Conventional engineering methods are used to properly select the size and packing density of the gravel and silica and, accordingly, to select the desired filter media removal efficiency.", "[0038] Normal flow of the process fluid through the piping apparatus is shown in FIG. 3. Fluid from the cooling tower or other application enters the piping apparatus 16 through the process fluid conduit 22 .", "The process fluid then flows into the first manifold 20 , where it is directed into the housing 14 of the treatment device 10 via the inlet conduit 24 .", "The process fluid then percolates down through the filter media 12 contained by the treatment device 10 .", "The now filtered fluid flows out of the housing 14 through the outlet conduit 26 .", "The filtered fluid is then directed through the second manifold 21 and out of the piping assembly 16 through the return conduit 28 , for reuse in the cooling tower or other application.", "[0039] By introducing the process fluid tangentially into the treatment device 10 , the fluid is caused to swirl above the silica bed.", "The swirling assists in preventing channeling through the filter media 12 .", "Moreover, the velocity of the swirling fluid is greater near the peripheral than the center, disturbing the silica bed to become slightly coned shaped.", "The cone shape increases the effective surface area of the silica bed and, hence, its capacity to treat fluid.", "Overall, the swirling, in conjunction with the coned silica bed, enables the filter bed to operate at an increased flow rate of approximately 25 to 30 percent.", "The device 10 can be configured to treat various flow rates.", "Notwithstanding, it is expected that a common treatment capacity of the present invention will be about 25-30 gals/min/ft 2 .", "[0040] Swirling the process fluid is also advantageous in that it imparts a centripetal force component to the flow whereby suspended solids are forced outwardly to the circular sidewall 48 where a percentage of the suspended solids are kept in suspension.", "By temporarily or permanently keeping solids in suspension, fewer particles become deeply embedded in the filter media 12 or in the interstitial spacing of the media 12 .", "Accordingly, upon backwashing, suspended solids quickly separate from the filter media 12 .", "Since particles are more efficiently removed from the filter media 12 , significantly less backwash fluid, in the range of about 50-60 percent, is required than with conventional filters of similar treatment capacity.", "This efficiency difference exists because traditional filters linearly introduce fluid through a filter media 12 which drives the particles deeply into the media 12 where they become impacted.", "Consequently, greater backwash flow is required to remove particles from the interstitial spaces deep within the filter media 12 .", "[0041] Initially, process fluid is tangentially fed into the treatment device 10 through the inlet conduit 24 to impart a swirling motion to the process fluid above the upper surface of the silica bed.", "The swirling fluid causes the silica bed to become coned, increasing the silica bed's effective surface area.", "Since the surface area is enlarged, the rate in which the silica bed can treat the process fluid is increased.", "[0042] Additionally, by causing the process fluid to swirl, a percentage of the suspended solids is maintained in suspension above the silica bed while the process fluid passes downward through the filter media 12 where the remaining solids are stripped out from the process fluid.", "Hence, swirling the process fluid reduces particulate matter loading to the filter media 12 , and reduces the amount of particles that would have become deeply imbedded or impacted in the filter media 12 .", "Upon passing through the filter media 12 , the purified fluid egresses the housing 14 through outlet conduit 26 disposed at the bottom of the housing 14 .", "The cleansed effluent is returned to the cooling tower for reuse.", "[0043] In order to effectuate backwashing, flow is reversed through the treatment device 10 so that process fluid, external fluid, or collected effluent, flows into the device 10 through the outlet conduit 26 , is forced upwardly through the filter media 12 , then exits the housing 14 through the inlet conduit 24 for proper disposal.", "As an example, for the device 10 to treat 25 - 30 gals/min/ft 2 , backwash fluid is introduced into the filter media 12 at a preferred rate of about 25 gal/min/ft 2 to fully fluidized the filter media 12 and to carry particles having a specific gravity that is less than that of gravel and silica from the housing 14 .", "The freeboard within the housing 14 between the upper surface of the silica bed and the inlet conduit 24 is sufficient to enable settling of any silica which may be carried up by the rising backwash fluid.", "The frequency of backwashing can be controlled by a pressure switch, timer or manually actuated.", "When using a pressure switch, the preferred pressure drop is approximately 5-12 pounds/inch 2 .", "[0044] As backwash fluid is passed upwardly through the filter media 12 , particles with a lower specific gravity than that of gravel or silica are carried through the filter media 12 and egress the housing 14 via the inlet conduit 24 for proper disposal.", "There is sufficient freeboard between the silica bed and the inlet conduit 24 to allow silica, which have become entrained in the backwash, to settle back to the silica bed.", "[0045] Complete fluidization of the filter media 12 during backwash is preferred in order to thoroughly clean the media 12 of imbedded particles, re-stratify the filter media 12 and to break any bonding of the media 12 (for example, calcification from hard fluid).", "If the filter media 12 is not completely fluidized during backwashing, the filter media 12 may see no flow or minimal flow conditions.", "At these low flow areas, captured particles are not removed and the media 12 is not fully re-stratified.", "No flow conditions combined with non-removed foreign particles are detrimental since they provide a breeding ground for bacteria.", "Furthermore, an unfluidized filter media 12 becomes compacted, reducing the treatment capacity of the treatment device, and thus requiring replacement.", "[0046] Complete fluidization of the filter media 12 includes the steps of lifting the entire filter media 12 from its fully packed condition and allowing it to expand at least 30 percent.", "This allows gravel, silica and captured particle to break free from neighboring matter.", "[0047] Under typical loading conditions, the backwashing method of the present invention is so effective at removing particulate matter that significant bacteria growth does not occur in the filter media 12 .", "Additionally, a flocking agent is not typically required since the treatment device 10 removes suspended solids at such a high efficiency.", "Notwithstanding the superior performance of the treatment device 10 , under certain situation it may be desirable to provide chlorine or bromine for bacteria treatment, or a flocking agent, such as alum.", "As such, known automated or manual devices can be added to the fluid treatment device 10 .", "[0048] When utilizing process fluid backwash as exemplified in FIG. 4, the process fluid flows in through the process fluid conduit 22 .", "Through the use of a series of actuators 23 , the fluid flow is directed across a check valve 36 .", "In normal operation, the check valve 36 remains in a closed position, with the process fluid not exerting enough pressure upon it to cause the valve to open.", "However, when utilizing external fluid in the backwash configuration, the process fluid is physically blocked from its normal course of flow from the process fluid conduit 20 into the inlet conduit 24 .", "The pressure inside the piping assembly 16 increases as more process fluid is forced in therein.", "This pressure increase causes the check valve 36 (not shown) to open.", "The process fluid can then flow from the process conduit 20 into the outlet conduit 26 , and enter the treatment device 10 from the reverse direction.", "Note that the return conduit 28 has also been blocked in this configuration, by a corresponding actuator movement to that described previously.", "The process fluid flows from the second manifold 21 into the outlet conduit 26 where it enters the treatment device 10 .", "The treatment device 10 then floods until the effluent level therein rises to the level of the inlet conduit 24 .", "The effluent then flows out of the treatment device 10 through the inlet conduit 24 .", "The backwashed effluent is then directed to the waste conduit 30 , where it exits the piping assembly 16 to a holding tank, treatment pond, or the like.", "[0049] As shown in FIG. 5, when utilizing the external fluid for the backwash media, external fluid is allowed to enter the piping apparatus 16 from the external conduit 27 where it is then directed into the manifold 20 .", "The one-way check valve 36 (not shown) prevents the external fluid from flowing back through the process fluid conduit 22 , and into the cooling tower.", "The external fluid flows from the second manifold 21 where it is directed by the actuator 23 (not shown) into the outlet conduit 26 where it enters the treatment device 10 .", "The treatment device 10 then floods until the effluent level therein rises to the level of the inlet conduit 24 .", "The effluent then flows out of the treatment device 10 through the inlet conduit 24 .", "The backwashed effluent is then directed to the waste conduit 30 , where it exits the piping assembly 16 to a holding tank, treatment pond, or the like.", "SUMMARY OF THE ACHIEVEMENT OF THE OBJECTS OF THE INVENTION [0050] From the foregoing, it is readily apparent that we have invented a piping apparatus for use with a fluid treatment device having a filter media for purifying process fluid.", "The piping apparatus allows for easy selection between a plurality of backwash sources, preferably between an internal or process fluid source, and an external or external fluid source.", "[0051] It is to be understood that the foregoing description and specific embodiments are merely illustrative of the best mode of the invention and the principles thereof, and that various modifications and additions may be made to the apparatus by those skilled in the art, without departing from the spirit and scope of this invention, which is therefore understood to be limited only by the scope of the appended claims." ]
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention generally relates to a power supply adapter, and more particularly to a power supply adapter with a foldable plug module. [0003] 2. The Related Art [0004] A power supply adapter is widely used in many electronic devices for converting alternating current (AC) power into direct current (DC) power so as to supply the required DC power to operate or charge the electronic devices. [0005] A conventional power supply adapter is disclosed in U.S. Pat. No. 6,548,755. According to disclosure of the patent, the power supply adapter includes a first casing, a second casing, a rotatable cylinder and a projecting plug. The first casing defines a cavity at a front end thereof. Two vertical plates are mounted on the second casing for supporting the rotatable cylinder. The projecting plug is formed on a front end of the rotatable cylinder and extends from a cavity space defined by the front end of the first casing and the second casing. By rotating the rotatable cylinder, the angle of the projecting plug is changed. [0006] However, the power supply adapter of this type fails to locate the projecting plug stably in place when the projecting plug is raised to mate with other electronic apparatus, thus leading to unstable connection between the projecting plug and the electronic apparatus. Then, an improved power supply adapter capable of locating the projecting plug stably is desired. SUMMARY OF THE INVENTION [0007] Accordingly, an object of the present invention is to provide a power supply adapter capable of firming a plug module thereof. The power supply adapter comprises a casing defining at least one inserting groove therein, at least one resilient piece disposed in the casing and having a locating portion and a resisting portion extended gradually upward from the locating portion, and a plug module rotatablely disposed in the casing. The plug module has at least one retaining block disposed in the inserting groove of the casing and capable of rotating around the resisting portion of the resilient piece. A connecting terminal runs through the retaining block to form an inserting portion and a projecting portion at opposite sides of the retaining block. The projecting portion is capable of compressing the resisting portion when the inserting portion is raised erectly to be exposed externally from the inserting groove. [0008] As described above, the power supply adapter utilizes the resilient piece to fix the inserting portion of the plug module because the resisting portion exerts elastic force upon the projecting portion when the projecting portion compresses the resisting portion, so as that the inserting portion is capable of stably connecting with other electronic apparatus. BRIEF DESCRIPTION OF THE DRAWINGS [0009] The present invention will be apparent to those skilled in the art by reading the following description of a preferred embodiment thereof, with reference to the attached drawings, in which: [0010] FIG. 1 is an exploded view of a power supply adapter according to an embodiment of the present invention; [0011] FIG. 2 is a perspective view of an upper casing of the power supply adapter of FIG. 1 while viewed from inside of the upper casing; [0012] FIG. 3 is an assembly view of the power supply adapter without the upper casing; [0013] FIG. 4 is a perspective view of the power supply adapter of FIG. 1 ; [0014] FIG. 5 is a cross-sectional view of the power supply adapter of which plug module is raised; [0015] FIG. 6 is a cross-sectional view of the power supply adapter of which the plug module is folded to a stowed position; and [0016] FIG. 7 is a perspective view of a power supply adapter according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0017] Referring to FIG. 1 , a power supply adapter 1 in accordance with the present invention includes an upper casing 10 , a bearing frame 20 , a locating screw 30 , a plug module 40 , a pair of resilient pieces 50 , a printed circuit board (PCB) 60 , a pair of conductive members 70 and a lower casing 80 which can couple with the upper casing 10 to form a receiving space 13 therebetween for receiving the bearing frame 20 , the locating screw 30 , the plug module 40 , the two resilient pieces 50 , the PCB 60 and the two conductive members 70 therein. [0018] With reference to FIG. 1 and FIG. 2 , the upper casing 10 has a top board 11 and two sideboards 12 extended downward from two lateral sides of the top board 11 respectively. Partial material of the front portion of the top board 11 is removed so as to form a bottom portion 141 , a rear portion 142 and two sidewalls (not labeled). The bottom portion 141 , the rear portion 142 and the two sidewalls define in conjunction a receiving recess 14 . Two separate inserting grooves 15 are defined on the top board 11 and communicate with inside of the upper casing 10 . The inserting grooves 15 are arranged in the rear portion 142 respectively to communicate with the receiving recess 14 . A first hollow locating pillar 16 is protruded upon an opposite side of the bottom portion 141 at a substantially middle portion thereof. Two pairs of locating posts 17 are also extended from the side, upon which the first locating pillar 16 is protruded, of the bottom portion 141 . One pair of the locating posts 17 is disposed at opposite sides of the first locating pillar 16 and the other pair of the locating posts 17 is adjacent to the rear portion of the opposite side of the bottom portion 141 . A reverse side of the top board 11 defines two pairs of first vertical plates 18 which protrude downward. Every one pair of the first vertical plates 18 is disposed at opposite sides of the inserting groove 15 . Each of the vertical plates 18 defines a first semicircular concave gap 181 on a bottom portion thereof. A front end of each of the vertical plates 18 connects with a reverse side of the rear portion 142 . A retaining plate 19 extends downward from the reverse side of the top board 11 . Two ends of the retaining plate 19 respectively connect with rear ends of the vertical plates 18 adjacent to the sideboards 12 . The retaining plate 19 defines a retaining hole 191 at a top portion thereof. [0019] Referring to FIG. 1 , the bearing frame 20 has a base wall 21 , two sidewalls 23 extending upward from opposite sides of the base wall 21 and a rear wall 26 extending upward from a rear side of the base wall 21 and connecting with the sidewalls 23 . A front portion of the base wall 21 defines two first locating holes 25 at opposite sides thereof. The front portion of the base wall 21 stretches forwardly from a middle portion thereof to form a tongue portion 22 defining a second hollow locating pillar 221 downward. Each of the sidewalls 23 defines a second semicircular concave gap 231 thereon. An opening 242 is defined in the middle of the rear wall 26 . A locking portion 24 extends upward from the rear of the base wall 21 corresponding to the middle position of the opening 242 . A top end of the locking portion 24 protrudes backward to form a hook portion 241 thereon. [0020] With reference to FIG. 1 and FIG. 3 , the plug module 40 includes a pair of retaining blocks 42 keeping a distance from each other. Each of the retaining blocks 42 is of substantially square-shape and defines an arc-shaped surface 421 which smoothly connects a bottom surface with a rear surface of the retaining block 42 . A central shaft 41 transversely passes through the center of the retaining blocks 42 and two ends thereof respectively protrude outside. Two sheet-shaped connecting terminals 43 longitudinally run through the middle of the retaining blocks 42 and the central shaft 41 respectively. The connecting terminal 43 has an inserting portion 431 at front of the retaining block 42 and a projecting portion 432 extended out of the back portion of the retaining block 42 . [0021] Referring to FIG. 1 , each of the resilient pieces 50 is conductive and has a planar locating portion 51 defining two second locating holes 511 therein. A front end of the locating portion 51 perpendicularly extends downward to form a contact portion 52 . A protrusion 521 is projected forwardly from the contact portion 52 . An arc-shaped resisting portion 53 smoothly extends rearward and upward from a rear end of the locating portion 51 . [0022] The PCB 60 defines two pairs of inserting holes 61 at a front end thereof and a plurality of fixing notches 62 at opposite sides thereof. [0023] Each conductive member 70 is of substantial M-shape. The conductive member 70 has a receiving groove 71 which gradually becomes wider and wider from top to bottom. Two inserting pins 72 extend downward from opposite sides of the receiving groove 71 . [0024] The lower casing 80 defines a plurality of wedging blocks 81 on a bottom surface thereof and connected with opposite sides thereof. [0025] Please refer to FIG. 1 to FIG. 4 . In assembly, the locating portions 51 of the resilient pieces 50 are respectively disposed on the opposite sides of the base wall 21 of the bearing frame 20 . The resisting portion 53 is disposed above the base wall 21 . The second locating hole 511 disposed at the rear of the locating portion 51 and the first locating hole 25 of the bearing frame 20 have the same axle center. The plug module 40 is placed on the bearing frame 20 . The two ends of the central shaft 41 are respectively received in the second concave gaps 231 . The retaining blocks 42 are disposed on the resisting portions 53 . The arc-shaped surface 421 of the retaining block 42 touches a surface of the resisting portion 53 . Then the combination of the bearing frame 20 , the plug module 40 and the resilient pieces 50 couples with the upper casing 10 . The first locating pillar 16 is inserted in the second locating pillar 221 of the bearing frame 20 . Then the locating screw 30 is mounted in the second locating pillar 221 for fixing the bearing frame 20 with the upper casing 10 . The locating posts 17 are respectively disposed in both the second locating holes 511 and the first locating holes 25 . The vertical plates 18 adjacent to the sideboard 12 are coupled with the sidewalls 23 of the bearing frame 20 . The two ends of the central shaft 41 are placed in the first concave gaps 181 and the second concave gaps 231 . The retaining blocks 42 are disposed in the inserting grooves 15 and the inserting portions 431 respectively protrude outside. The hook portion 241 of the bearing frame 20 is located in the retaining hole 191 of the upper casing 10 . The conductive members 70 are located on the PCB 60 for electrical connection. The inserting pins 72 are respectively inserted in the inserting holes 61 . Then the contact portions 52 of the resilient pieces 50 are received in the receiving grooves 71 . The PCB 60 is mounted in the lower casing 80 . The wedging blocks 81 engage with the fixing notches 62 . [0026] Please refer to FIG. 5 and FIG. 6 . When the power supply adapter 1 is in use, the inserting portions 431 of the connecting terminals 43 of the plug module 40 are raised erectly to connect with other electronic apparatus. At this time, the projecting portions 432 of the connecting terminals 43 compress the resisting portions 53 of the resilient pieces 50 , which not only enable the electrical connection between the PCB 60 and the connecting terminals 43 , but also ensure the inserting portions 431 stably connect with the electronic apparatus because of the resisting portions 53 exerting elastic force upon the projecting portions 432 . When the power supply adapter 1 is not in use, the inserting portions 431 are laid and received in the receiving recess 14 of the upper casing 10 for conveniently being carried. Meanwhile, the projecting portions 432 come off the resisting portions 53 . [0027] As described above, the power supply adapter 1 of the present invention utilizes the resilient pieces 50 to attain electrical connection with the PCB 60 and simultaneously fix the inserting portions 431 of the plug module 40 , so that the inserting portions 431 are capable of stably connecting with the electronic apparatus. [0028] The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. Such as another embodiment shown in FIG. 7 , in which the rear portion 142 of the upper casing 10 extends forward into the receiving recess 14 to divide the receiving recess 14 into two. When the power supply adapter 1 is not in use, the inserting portions 431 are received in the corresponding receiving recesses 14 and located at two sides of the rear portion 142 so as to prevent the inserting portions 431 from being broken and be conveniently carried. Such modifications and variations that may be apparent to those skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims.
A power supply adapter includes a casing defining at least one inserting groove therein, at least one resilient piece disposed in the casing and having a locating portion and a resisting portion extended gradually upward from the locating portion, and a plug module rotatablely disposed in the casing. The plug module has at least one retaining block disposed in the inserting groove of the casing and capable of rotating around the resisting portion of the resilient piece. A connecting terminal runs through the retaining block to form an inserting portion and a projecting portion at opposite sides of the retaining block. The projecting portion is capable of compressing the resisting portion when the inserting portion is raised erectly to be exposed externally from the inserting groove.
Briefly summarize the main idea's components and working principles as described in the context.
[ "BACKGROUND OF THE INVENTION [0001] 1.", "Field of the Invention [0002] The present invention generally relates to a power supply adapter, and more particularly to a power supply adapter with a foldable plug module.", "[0003] 2.", "The Related Art [0004] A power supply adapter is widely used in many electronic devices for converting alternating current (AC) power into direct current (DC) power so as to supply the required DC power to operate or charge the electronic devices.", "[0005] A conventional power supply adapter is disclosed in U.S. Pat. No. 6,548,755.", "According to disclosure of the patent, the power supply adapter includes a first casing, a second casing, a rotatable cylinder and a projecting plug.", "The first casing defines a cavity at a front end thereof.", "Two vertical plates are mounted on the second casing for supporting the rotatable cylinder.", "The projecting plug is formed on a front end of the rotatable cylinder and extends from a cavity space defined by the front end of the first casing and the second casing.", "By rotating the rotatable cylinder, the angle of the projecting plug is changed.", "[0006] However, the power supply adapter of this type fails to locate the projecting plug stably in place when the projecting plug is raised to mate with other electronic apparatus, thus leading to unstable connection between the projecting plug and the electronic apparatus.", "Then, an improved power supply adapter capable of locating the projecting plug stably is desired.", "SUMMARY OF THE INVENTION [0007] Accordingly, an object of the present invention is to provide a power supply adapter capable of firming a plug module thereof.", "The power supply adapter comprises a casing defining at least one inserting groove therein, at least one resilient piece disposed in the casing and having a locating portion and a resisting portion extended gradually upward from the locating portion, and a plug module rotatablely disposed in the casing.", "The plug module has at least one retaining block disposed in the inserting groove of the casing and capable of rotating around the resisting portion of the resilient piece.", "A connecting terminal runs through the retaining block to form an inserting portion and a projecting portion at opposite sides of the retaining block.", "The projecting portion is capable of compressing the resisting portion when the inserting portion is raised erectly to be exposed externally from the inserting groove.", "[0008] As described above, the power supply adapter utilizes the resilient piece to fix the inserting portion of the plug module because the resisting portion exerts elastic force upon the projecting portion when the projecting portion compresses the resisting portion, so as that the inserting portion is capable of stably connecting with other electronic apparatus.", "BRIEF DESCRIPTION OF THE DRAWINGS [0009] The present invention will be apparent to those skilled in the art by reading the following description of a preferred embodiment thereof, with reference to the attached drawings, in which: [0010] FIG. 1 is an exploded view of a power supply adapter according to an embodiment of the present invention;", "[0011] FIG. 2 is a perspective view of an upper casing of the power supply adapter of FIG. 1 while viewed from inside of the upper casing;", "[0012] FIG. 3 is an assembly view of the power supply adapter without the upper casing;", "[0013] FIG. 4 is a perspective view of the power supply adapter of FIG. 1 ;", "[0014] FIG. 5 is a cross-sectional view of the power supply adapter of which plug module is raised;", "[0015] FIG. 6 is a cross-sectional view of the power supply adapter of which the plug module is folded to a stowed position;", "and [0016] FIG. 7 is a perspective view of a power supply adapter according to another embodiment of the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0017] Referring to FIG. 1 , a power supply adapter 1 in accordance with the present invention includes an upper casing 10 , a bearing frame 20 , a locating screw 30 , a plug module 40 , a pair of resilient pieces 50 , a printed circuit board (PCB) 60 , a pair of conductive members 70 and a lower casing 80 which can couple with the upper casing 10 to form a receiving space 13 therebetween for receiving the bearing frame 20 , the locating screw 30 , the plug module 40 , the two resilient pieces 50 , the PCB 60 and the two conductive members 70 therein.", "[0018] With reference to FIG. 1 and FIG. 2 , the upper casing 10 has a top board 11 and two sideboards 12 extended downward from two lateral sides of the top board 11 respectively.", "Partial material of the front portion of the top board 11 is removed so as to form a bottom portion 141 , a rear portion 142 and two sidewalls (not labeled).", "The bottom portion 141 , the rear portion 142 and the two sidewalls define in conjunction a receiving recess 14 .", "Two separate inserting grooves 15 are defined on the top board 11 and communicate with inside of the upper casing 10 .", "The inserting grooves 15 are arranged in the rear portion 142 respectively to communicate with the receiving recess 14 .", "A first hollow locating pillar 16 is protruded upon an opposite side of the bottom portion 141 at a substantially middle portion thereof.", "Two pairs of locating posts 17 are also extended from the side, upon which the first locating pillar 16 is protruded, of the bottom portion 141 .", "One pair of the locating posts 17 is disposed at opposite sides of the first locating pillar 16 and the other pair of the locating posts 17 is adjacent to the rear portion of the opposite side of the bottom portion 141 .", "A reverse side of the top board 11 defines two pairs of first vertical plates 18 which protrude downward.", "Every one pair of the first vertical plates 18 is disposed at opposite sides of the inserting groove 15 .", "Each of the vertical plates 18 defines a first semicircular concave gap 181 on a bottom portion thereof.", "A front end of each of the vertical plates 18 connects with a reverse side of the rear portion 142 .", "A retaining plate 19 extends downward from the reverse side of the top board 11 .", "Two ends of the retaining plate 19 respectively connect with rear ends of the vertical plates 18 adjacent to the sideboards 12 .", "The retaining plate 19 defines a retaining hole 191 at a top portion thereof.", "[0019] Referring to FIG. 1 , the bearing frame 20 has a base wall 21 , two sidewalls 23 extending upward from opposite sides of the base wall 21 and a rear wall 26 extending upward from a rear side of the base wall 21 and connecting with the sidewalls 23 .", "A front portion of the base wall 21 defines two first locating holes 25 at opposite sides thereof.", "The front portion of the base wall 21 stretches forwardly from a middle portion thereof to form a tongue portion 22 defining a second hollow locating pillar 221 downward.", "Each of the sidewalls 23 defines a second semicircular concave gap 231 thereon.", "An opening 242 is defined in the middle of the rear wall 26 .", "A locking portion 24 extends upward from the rear of the base wall 21 corresponding to the middle position of the opening 242 .", "A top end of the locking portion 24 protrudes backward to form a hook portion 241 thereon.", "[0020] With reference to FIG. 1 and FIG. 3 , the plug module 40 includes a pair of retaining blocks 42 keeping a distance from each other.", "Each of the retaining blocks 42 is of substantially square-shape and defines an arc-shaped surface 421 which smoothly connects a bottom surface with a rear surface of the retaining block 42 .", "A central shaft 41 transversely passes through the center of the retaining blocks 42 and two ends thereof respectively protrude outside.", "Two sheet-shaped connecting terminals 43 longitudinally run through the middle of the retaining blocks 42 and the central shaft 41 respectively.", "The connecting terminal 43 has an inserting portion 431 at front of the retaining block 42 and a projecting portion 432 extended out of the back portion of the retaining block 42 .", "[0021] Referring to FIG. 1 , each of the resilient pieces 50 is conductive and has a planar locating portion 51 defining two second locating holes 511 therein.", "A front end of the locating portion 51 perpendicularly extends downward to form a contact portion 52 .", "A protrusion 521 is projected forwardly from the contact portion 52 .", "An arc-shaped resisting portion 53 smoothly extends rearward and upward from a rear end of the locating portion 51 .", "[0022] The PCB 60 defines two pairs of inserting holes 61 at a front end thereof and a plurality of fixing notches 62 at opposite sides thereof.", "[0023] Each conductive member 70 is of substantial M-shape.", "The conductive member 70 has a receiving groove 71 which gradually becomes wider and wider from top to bottom.", "Two inserting pins 72 extend downward from opposite sides of the receiving groove 71 .", "[0024] The lower casing 80 defines a plurality of wedging blocks 81 on a bottom surface thereof and connected with opposite sides thereof.", "[0025] Please refer to FIG. 1 to FIG. 4 .", "In assembly, the locating portions 51 of the resilient pieces 50 are respectively disposed on the opposite sides of the base wall 21 of the bearing frame 20 .", "The resisting portion 53 is disposed above the base wall 21 .", "The second locating hole 511 disposed at the rear of the locating portion 51 and the first locating hole 25 of the bearing frame 20 have the same axle center.", "The plug module 40 is placed on the bearing frame 20 .", "The two ends of the central shaft 41 are respectively received in the second concave gaps 231 .", "The retaining blocks 42 are disposed on the resisting portions 53 .", "The arc-shaped surface 421 of the retaining block 42 touches a surface of the resisting portion 53 .", "Then the combination of the bearing frame 20 , the plug module 40 and the resilient pieces 50 couples with the upper casing 10 .", "The first locating pillar 16 is inserted in the second locating pillar 221 of the bearing frame 20 .", "Then the locating screw 30 is mounted in the second locating pillar 221 for fixing the bearing frame 20 with the upper casing 10 .", "The locating posts 17 are respectively disposed in both the second locating holes 511 and the first locating holes 25 .", "The vertical plates 18 adjacent to the sideboard 12 are coupled with the sidewalls 23 of the bearing frame 20 .", "The two ends of the central shaft 41 are placed in the first concave gaps 181 and the second concave gaps 231 .", "The retaining blocks 42 are disposed in the inserting grooves 15 and the inserting portions 431 respectively protrude outside.", "The hook portion 241 of the bearing frame 20 is located in the retaining hole 191 of the upper casing 10 .", "The conductive members 70 are located on the PCB 60 for electrical connection.", "The inserting pins 72 are respectively inserted in the inserting holes 61 .", "Then the contact portions 52 of the resilient pieces 50 are received in the receiving grooves 71 .", "The PCB 60 is mounted in the lower casing 80 .", "The wedging blocks 81 engage with the fixing notches 62 .", "[0026] Please refer to FIG. 5 and FIG. 6 .", "When the power supply adapter 1 is in use, the inserting portions 431 of the connecting terminals 43 of the plug module 40 are raised erectly to connect with other electronic apparatus.", "At this time, the projecting portions 432 of the connecting terminals 43 compress the resisting portions 53 of the resilient pieces 50 , which not only enable the electrical connection between the PCB 60 and the connecting terminals 43 , but also ensure the inserting portions 431 stably connect with the electronic apparatus because of the resisting portions 53 exerting elastic force upon the projecting portions 432 .", "When the power supply adapter 1 is not in use, the inserting portions 431 are laid and received in the receiving recess 14 of the upper casing 10 for conveniently being carried.", "Meanwhile, the projecting portions 432 come off the resisting portions 53 .", "[0027] As described above, the power supply adapter 1 of the present invention utilizes the resilient pieces 50 to attain electrical connection with the PCB 60 and simultaneously fix the inserting portions 431 of the plug module 40 , so that the inserting portions 431 are capable of stably connecting with the electronic apparatus.", "[0028] The foregoing description of the present invention has been presented for purposes of illustration and description.", "It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching.", "Such as another embodiment shown in FIG. 7 , in which the rear portion 142 of the upper casing 10 extends forward into the receiving recess 14 to divide the receiving recess 14 into two.", "When the power supply adapter 1 is not in use, the inserting portions 431 are received in the corresponding receiving recesses 14 and located at two sides of the rear portion 142 so as to prevent the inserting portions 431 from being broken and be conveniently carried.", "Such modifications and variations that may be apparent to those skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims." ]
REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser. No. 12/203,047, filed Sep. 2, 2008, which claims priority to U.S. Provisional Patent Application Nos. 60/969,452 filed Aug. 31, 2007 and 61/083,839 filed Jul. 25, 2008, and to PCT International Patent Application PCT/NZ2008/000225 filed Sep. 1, 2008, and is a continuation-in-part of U.S. patent application Ser. No. 11/745,993 filed May 8, 2007, now U.S. Pat. No. 7,649,086, which claims priority to U.S. Provisional Patent Application Nos. 60/746,682 filed May 8, 2006 and 60/869,057 filed Dec. 7, 2006. FIELD OF THE INVENTION [0002] The present invention relates to lignin and other products, such as xylose, xylitol, furfural, fermentable sugars, cellulose and hemi-cellulose products isolated from plant materials, methods for isolating such products from plant materials, and compositions containing such plant-derived products. BACKGROUND [0003] Mounting global energy demands have dramatically increased the cost of fossil-fuel-based energy sources and petrochemicals. And, the environment has been harmed, perhaps irreparably, in an effort to meet this demand by discovery and extraction of fossil-fuel feedstocks, and by processing of those raw feedstocks to produce ever increasing amounts of fuel, petrochemicals, and the like. Petrochemicals furthermore provide the majority of raw materials used in many plastics and chemical industries. The present invention is directed to providing isolated, plant-derived, renewable and sustainable compositions that have multiple utilities and that provide renewable and sustainable substitutes for fossil-fuel derived and petrochemical feedstocks. [0004] Lignin is a complex, high molecular weight polymer that occurs naturally in plant materials, and is one of the most abundant renewable raw materials available on earth. Lignin is present in all vascular plants and constitutes from about a quarter to a third of the dry mass of wood. It is covalently linked to hemicellulose in plant cell walls, thereby crosslinking a variety of plant polysaccharides. Lignin is characterized by relatively high strength, rigidity, impact strength and high resistance to ultra-violet light and, in wood, has a high degree of heterogeneity, lacking a defined primary structure. [0005] Lignin molecules are generally large, cross-linked macromolecules and may have molecular masses in excess of 10,000 in their native form in plant material. The degree of lignin polymerization in nature is difficult to determine, since lignin is fragmented during extraction. Various types of lignin have been characterized and described, with the lignin properties generally depending on the extraction methodology. There are three monolignol monomers, which are methoxylated to various degrees: p-coumaryl alcohol, coniferyl alcohol, and synapyl alcohol. These monomers are incorporated in lignin polymers in the form of phenylpropanoids p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S). Different plants exhibit different proportions of the phenylpropanoids. [0006] The polyphenolic nature of lignin and its low toxicity, together with many additional properties (such as its dispersing, binding, complexing and emulsifying, thermal stability, specific UV-absorbing, water repellent and conductivity characteristics), make it an attractive renewable replacement for toxic and expensive fossil fuel-derived polymer feedstocks. Unlike synthetic polymers, lignin is biodegradable in nature. In spite of its biodegradability, lignin is known to be one of the most durable biopolymers available. [0007] Large quantities of lignin are produced as a by-product of the pulp and paper industry. Despite its unique and desirable characteristics as a natural product with multiple beneficial chemical, physical and biological properties, and its abundance, lignin isolated from plant materials remains largely under-exploited. The heterogeneity and low reactivity of lignin recovered from waste effluent produced by the pulp and paper industry has resulted in limited industrial utilization of this highly abundant and renewable natural product. [0008] Lignin is recovered from sulfite or Kraft wood pulping processes as lignosulfonates containing significant amounts of contaminants. The recovered lignin molecules lack stereoregularity, with repeating units being heterogeneous and complex. In general, lignin obtained as a by-product of the Kraft process (referred to as Kraft lignin) requires further processing and/or modification, as described in U.S. Pat. Nos. 5,866,642 and 5,202,403, in order to increase its reactivity and to allow its use in the formation of higher value products. Kraft lignin preparations contain a mixture of lignin sulfonate and degraded lignin, together with numerous decomposition products, such as sugars, free sulfurous acid and sulfates. The phenolic structures of the Kraft lignin are highly modified and condensed. The sulfite process for wood treatment produces a water soluble sulfonated lignin preparation that contains a high content of sugars, sugar acids and sugar degradation products, as well as resinous extractives and organic constituents with multiple coordination sites. The costs associated with the purification and functionalization required to make these low grade lignin preparations useful have limited their utilization in high value application markets. [0009] The use of organic solvents for lignin extraction prior to carbohydrate hydrolysis as disclosed, for example, in U.S. Pat. Nos. 4,764,596, 5,788,812 and 5,010,156, was shown to improve the quality of the resulting lignin, but the use of a catalyst in combination with various types of solvents under severe conditions often produced lignin having altered reactivity (McDonough (1992) TAPPI Solvent Pulping Seminar, Boston, Mass., The Institute of Paper Science and Technology ; Pan and Sano (2000) Holzforschung 54:61-65; Oliet et al. (2001) J. Wood Chem. Technol. 21:81-95; Xu et al. (2006) Industrial Crops and Products 23:180-193). [0010] The reactivity of lignin depends mainly on the presence and frequency of aliphatic, phenolic hydroxyl and carbonyl groups, which varies depending on the lignin source and the extraction process used to obtain the lignin. The average molecular weight and polydispersity of lignin in the preparation also has a great impact on its reactivity. [0011] As demonstrated in the many attempts to replace phenol with lignin in the formation of phenol-based resins, the low reactivity of the lignin means that only a small amount of phenol can be displaced without affecting the mechanical and physical properties of the final resin (çetin and Özmen (2002) Int. J. Adhesion and Adhesives 22:477-480; çetin and Özmen (2003) Turk. J. Agric. For. 27:183-189; Sellers et al. (2004) For. Prod. J. 54:45-51). Similar difficulties are encountered when lignin is employed in other types of applications. For example, the thermostability of lignin used to produce carbon fibers by spinning, as described in U.S. Pat. No. 6,765,028, and the carbonization of the resulting lignin fibers, are largely influenced by the method of lignin extraction and the origin and composition of the lignin (Kadla et al. (2002) Carbon 40:2913-2920). [0012] When acidic ethanol-extracted lignin was used as a polyol for the experimental preparation of polyurethane (PU), replacement of 35% to 50% of the PU resin was achieved without compromising the integrity of the lignin-based PU film (Vanderlaan and Thring (1998) Biomass and Bioenergy 14:525-531; Ni and Thring (2003) Int. J. Polymeric Materials 52:685-707). Smaller ratios of replacement of PU resin (<10%) have been achieved by direct blending of soda lignin in pre-formed PU resin (Ciobanu et al. (2004) Industrial Crops and Products 20:231-241). [0013] Polymer blending is also a convenient method to develop lignin based products with desirable properties. (See, e.g., Kubo and Kadla (2003) Biomacromolecules 4(3):561-567; Feldman et al. (2003) J. Appl. Polym. Sci. 89:2000-2010; Alexy et al. (2004) J. Appl. Polym. Sci. 94:1855-1860; Banu et al. (2006) J. Appl. Polym. Sci. 101:2732-2748) The efficiency and quality of the polymer blend is normally closely related to the chemical and physical properties of the lignin preparation, such as monomer type(s), molecular weight and distribution, which depends on the origin of the lignin and method used for its extraction, isolation and harvesting. [0014] Upgrading lignin through chemical functionalization has been shown to be a good strategy for the successful incorporation of plant-derived lignins in high value products. However, these reactions are costly when low grade or low reactivity lignin is used as the substrate for chemical modification. Large amounts of reactants are required, together with longer reaction times and higher temperatures, to achieve relatively low rates of transformation of low grade and low reactivity lignins. This adds to the cost of the lignin feedstock and reduces its desirability for use in various types of industrial processes. SUMMARY OF THE INVENTION [0015] In one aspect, the present invention provides isolated, high grade lignin polymers derived from plant materials, as well as methods for isolating lignin from plant materials, compositions comprising the high grade lignin polymers and methods for using such lignin polymers in high value products. The disclosed lignin is more suitable for use as a feedstock for making downstream products than lignin extracted from plant materials using alternative methods, such as acid or alkaline extraction or steam explosion techniques, and has distinct properties compared to lignin polymers isolated from plant materials using alternative techniques. [0016] The plant material employed in the disclosed methods for producing a high grade isolated lignin product is preferably a lignocellulosic plant material selected from the group consisting of: woody or herbaceous materials, agricultural and/or forestry plant materials and residues, and dedicated energy crops. In some embodiments, the plant material comprises a hardwood material, and in some embodiments the plant material comprises a coppicable hardwood material, such as a coppicable shrub. In certain embodiments, the plant material employed comprises a material selected from a group consisting of Salix (e.g., Salix schwerinii, Salix viminalis ), Poplar, Eucalyptus , Mesquite, Jatropha, Pine, switch grass, miscanthus, sugar cane bagasse, soybean stover, corn stover, rice straw and husks, cotton husks, barley straw, wheat straw, corn fiberwood fiber, oil palm (e.g., Elaeis guineensis, Eiaeis oleifera ) frond, trunk, empty fruit-bunch, kernels, fruit fibers, shell and residues of oil palm materials, and combinations thereof. Additional plant materials may be used. The present invention contemplates isolated lignin and other extraction products derived from any of these materials, and downstream products comprising lignin and other extraction products derived from any of these materials. [0017] In some embodiments, plant materials comprising a higher proportion of syringyl (S)-lignin compared to guaiacyl (G)-lignin are preferred for processing to recover high grade isolated lignin. Plant materials having a S:G lignin ratio of at least 1:1 are preferred for some applications; plant materials having a S:G lignin ratio of at least 2:1 are preferred for some applications; and plant materials having a S:G lignin ratio of at least 3:1 or about 4:1 are preferred for some applications. The present invention comprehends isolated lignin and other extraction products derived from such plant materials, as well as compositions comprising isolated lignin and other extraction products derived from such plant materials. [0018] In one aspect, high grade lignin and other extraction products may be isolated as a product of a solvent extraction process for treating plant materials such as the process disclosed in U.S. patent application Ser. No. 11/745,993, filed May 8, 2007 and published Nov. 8, 2007 as US 2007/0259412 A1, the disclosure of which is hereby incorporated by reference in its entirety. In this aspect, lignin is isolated from a plant material in a modified ORGANOSOLV™ (aqueous ethanol solvent) extraction process that involves contacting the plant material with a solution comprising up to about 70% ethanol in water at a temperature of approximately 170° C. to 210° C. and a pressure of from about 19-30 barg for a retention time sufficient to produce a “black liquor” solution containing lignin soluble in the aqueous ethanol solvent. In another aspect, lignin may be isolated from a plant material in a modified ORGANOSOLV™ (aqueous ethanol solvent) extraction process that involves contacting the plant material with a solution comprising up to about 80% ethanol in water, in some circumstances using a solution comprising from about 60% to about 80% ethanol in water, under conditions similar to those described above. [0019] The modified ORGANOSOLV™ extraction is preferably carried out substantially in the absence of an introduced acid catalyst. For example, the reaction mixture may contain less than 1% of an introduced acid catalyst and, according to some embodiments, the reaction mixture contains less than 0.5% of an introduced acid catalyst. In some embodiments, the modified ORGANOSOLV™ extraction process is carried out in the absence of an introduced acid catalyst. [0020] The black liquor produced using a modified ORGANOSOLV™ extraction process as described above may be flash evaporated to remove some of the solvent, and additional solvent may be steam-stripped from the liquor. The lignin may then be precipitated, separated by filtration and/or centrifugation, and dried. As a consequence of the mild nature of the modified ORGANOSOLV™ extraction process (treatment with aqueous ethanol solvent in the substantial absence of a biocatalyst), the extracted lignin is minimally modified from its native form and contains fewer contaminants (e.g., salts, sugars and/or degradation products) than lignins produced using Kraft or sulfite processes. The lignin produced by the modified ORGANOSOLV™ extraction process thus offers much greater potential as a bio-based feedstock material for use in a variety of processes and syntheses than lignin produced during paper pulp production or from other biomass fractionation processes using catalysts and more severe extraction conditions. [0021] High grade lignin of the present invention may thus be isolated from a plant material in a modified ORGANOSOLV™ extraction process that involves contacting the plant material with a solvent comprising up to 80% ethanol in water, in some embodiments from about 60% to 80% ethanol in water and, in some embodiments, about 70% ethanol in water. The temperature of the materials undergoing the modified ORGANOSOLV™ extraction process may be approximately 170° C. to 210° C., in some embodiments approximately 180° to 200° C., and in yet other embodiments approximately 185° to 195° C. The pressure in the reaction chamber during modified ORGANOSOLV™ processing is generally from about 19-30 barg. For any given solvent composition, desired temperatures during modified ORGANOSOLV™ processing produce pressures that substantially prevent the solvent from boiling. [0022] According to some embodiments, the solvent extraction is carried out on a substantially continuous processing basis, in a reaction vessel that provides co-current or countercurrent flow of solvent and biomass feedstock. The modified ORGANOSOLV™ process, as described herein, particularly employing continuous processing, reduces the re-condensation and re-deposition of lignin often seen in batch reactors by allowing removal of solvent at temperatures well above the normal boiling point of the solvent. Alternatively, the solvent extraction may be carried out as a batch reaction or, according to some embodiments, as a batch reaction repeated two or more times. The solids:liquid ratio during solvent extraction is preferably at least 1:1 and, in some embodiments may be at least 1:2, in some embodiments at least 1:3; and in yet additional embodiments up to about 1:4. [0023] Residence time of the plant material in the reaction chamber, or solvent extraction digester, is generally at least about 20 minutes and may be from about 20 to 80 minutes. In alternative embodiments, the residence time may be from about 30 to 70 minutes or, in yet other embodiments, from about 40 to 60 minutes. A residence time in the solvent extraction digester sufficient to produce a “black liquor” solution containing lignin soluble in the aqueous ethanol solvent is suitable. The modified ORGANOSOLV™ extraction is preferably carried out substantially in the absence of an acid or alkaline catalyst. For example, the reaction mixture may contain less than 1% of an introduced acid or alkaline catalyst and, according to some embodiments, the reaction mixture contains no introduced acid or alkaline catalyst. [0024] In certain embodiments, the modified ORGANOSOLV™ extraction is carried out at a pH (measured with a glass electrode at room temperature) in the range of from about 3 to 9.5. In yet other embodiments, the modified ORGANOSOLV™ extraction is carried out at a pH of more than about 4 and less than about 8 and, in still other embodiments, the modified ORGANOSOLV™ extraction is carried out at a pH of more than about 5 and less than about 7. [0025] In another embodiment, a hot water treatment may be used alone, or in combination with (e.g., following) a solvent extraction process, to extract additional lignin from plant material, and/or from a plant pulp material recovered following solvent extraction. Suitable hot water treatments may involve contacting the plant or pulp material with an aqueous solution (e.g., water) at an elevated temperature (e.g. from about 130° C. and 220° C.) and at an elevated a pressure (e.g. from about 2-25 barg) for a retention time sufficient to remove hemicellulose sugars from the plant and/or plant pulp material, and then separating the aqueous solution from the treated solids and harvesting isolated lignin from the aqueous solution to produce a high grade lignin product. [0026] Water-soluble sugars such as xylose, as well as acetic acid and/or furfural may also be recovered from the aqueous hot water treatment solution. The resulting plant pulp material may be further processed to hydrolyze cellulose present in the plant material to glucose. This further processing may, for example, involve saccarification and/or fermentation. In one embodiment, the resulting plant pulp material is contacted with: (i) an aqueous solution comprising cellulase, β-glucosidase and temperature-tolerant yeast, (ii) yeast growth media, and (iii) buffer to hydrolyze cellulose present in the plant pulp material to glucose, which in turn may be fermented to produce ethanol. [0027] Lignin extracted from plant materials in a solvent extraction process as described above may be isolated and harvested, for example, by depressurizing the black liquor removed from the solvent extraction process, and removing the solvent (using, e.g., flash cooling, steam stripping, and similar processes), followed by precipitation of lignin. Precipitation of isolated lignin may be accomplished, for example, by dilution of the solvent mixture (generally from about 2 to 10 times, by volume) with an aqueous solution such as water and, optionally, by lowering the pH to less than about 3 by addition of acid. Addition of acid is generally not required, or the requirements are minimal, for harvesting lignin extracted from Salix and other hardwoods, but acid addition may be desirable for precipitation of lignin derived from other plant materials. In general, the use of hydrochloric acid is preferred to the use of other mineral acids if acid addition is desirable for precipitating lignin. This may desirably reduce the formation of condensation reaction products during processing. The isolated lignin precipitate may be harvested by filtration or centrifugation or settling, and dried. [0028] Alternatively, lignin extracted from plant materials in a solvent extraction and/or a hot water process and solubilized in an aqueous solvent solution may be isolated, for example, using a dissolved-gas-flotation process (e.g., “DAF-like process”). The solubilized lignin and solvent solution (e.g., black liquor) is generally cooled and may optionally be filtered, and is then mixed with a gasified solution. The gasified solution is generally an aqueous solution such as water. The volume of gasified solution is preferably from about 2 to 10 times that of the lignin solvent solution. In one embodiment, black liquor may be introduced into a mixing device that provides conditions of generally high fluid shear to provide rapid and substantially complete mixing of gasified solution with the black liquor. The gasified solution may be supersaturated, for example, with a gas such as CO 2 , nitrogen, air, or a gas mixture. During mixing with the aqueous solution, the hydrophobic lignin precipitates and is immiscible in the aqueous solution. Gas bubbles attach to the precipitated lignin and transport the precipitated lignin to the surface of the vessel, where it may be harvested using a DAF clarifier or by physical removal of the precipitated, buoyant lignin particulates. This lignin separation technique is an effective and gentle processing technique for recovering high grade lignin isolated from plant material using solvent extraction techniques, and may additionally be used to isolate lignin extracted from plant material using other techniques for extracting lignin from plant materials. Lignin separation and harvesting using a dissolved-gas-flotation technique may be carried out on either a batch basis or a continuous or semi-continuous processing basis. [0029] In another aspect, methods for recovering lignin from an aqueous suspension of lignin are provided. These methods may be useful in recovering lignin which has been precipitated from an aqueous ethanol solution by dilution, and the precipitate subsequently washed in water. Such methods include adding at least one component selected from the group consisting of: ethanol at a concentration of less than 40% v/v; ammonium salts other than ammonium bicarbonate; and detergents other than Tween™ 80 or sodium dodecyl sulphate. This causes the lignin to flocculate, whereby the lignin may be readily harvested from the suspension. In certain embodiments, ethanol is added at a concentration of between about 2% and 38% v/v, for example at a concentration of about 9% to about 29% v/v. The ammonium salt may, for example, be ammonium sulfate or ammonium chloride, and may be added at a concentration greater than 4 mM. Detergents that may be effectively employed in such methods include, but are not limited to, Triton™ X-100, Triton™ X-114 and Nonidet™ P40. In one embodiment the detergent is added at a concentration greater than 4 ppm. This method can be useful for desalting any type of lignin preparation, to separate lignin from unreacted product and/or to selectively recover lignin sub-fractions for specific applications. [0030] Because of its superior quality and its distinctive properties and structure, the high grade isolated lignin disclosed herein may be preferred over lignin isolated using different methodologies in the formulation of lignin-containing materials. The high grade lignin disclosed herein may be introduced, for example, in a variety of carbon based materials to provide products having an equivalent or higher quality than those produced using fossil fuel-derived raw materials or feedstocks, or other plant-derived lignins. Because of its superior blending capacity, the high grade isolated lignin disclosed herein may also be introduced in generally high proportions in a variety of resins used in the formulation of adhesives, films, plastics, paints, coatings and foams. The disclosed isolated lignin is also suitably reactive with other materials containing cross-linkable functional groups and amenable to chemical modification, resulting in increased reactivity. In general, shorter reaction times are required, and lower amounts of reactant are used and lost in processing isolated lignin of the present invention, resulting in cost reduction and more efficient chemical lignin modification. Also, as a consequence of its substantial homogeneity and purity, the thermal degradation of the isolated lignin disclosed herein generally yields a less complex mixture of products that may be upgraded or purified in further processing. [0031] Isolated lignin of the present invention, derived from renewable and sustainable plant sources may be used, in many applications, as a substitute for petrochemicals and fossil fuel derived materials that are currently used as raw materials in the plastics and chemical industries. As a consequence of its distinctive structural properties, substantial homogeneity and composition, isolated lignin disclosed herein may be used, for example, as a renewable and sustainable phenol biopolymer for synthesizing phenolic and epoxy resins, providing a substitute feedstock for the petrochemical-based phenol polymers that are currently used as feedstocks for synthesizing phenolic and epoxy resins. [0032] Phenolic resins encompass a variety of products formed by the reaction of phenol and aldehydes. Phenolic resin based adhesive acts as a matrix for binding together various substrates, including wood, paper, fibers (e.g., fiberglass), and particles (e.g., wood flour, foundry sand, etc.), to form cross-linked composites. Other aromatic hydrocarbons used in these reactions include cresols, xylenols, and substituted phenols. The aldehydes are usually formaldehyde, paraformaldehyde and/or furfural. Various other additives and reinforcing compositions may also be used to provide resins and end-use materials having a variety of properties. [0033] Epoxy resins, like phenolic resins, are liquid or solid resins which cure to form hard, insoluble, chemical resistant plastics. Resins derived from bisphenol-A are among the most widely used epoxy resins. Bisphenol A is produced by liquid-phase condensation of phenol with acetone (a by-product of phenol synthesis). The chemistry of epoxy resin and the range of commercially available variations allow cured polymers to be produced with a very broad range of properties. The exceptional adhesion performance of epoxy resin is due to the presence of polar hydroxyl and ether groups in the backbone structure of the resin. Epoxy resins are also known for their chemical and heat resistance properties. There are many ways of modifying epoxy resins: for example, addition of fillers, flexibilizers, viscosity reducers, colorants, thickeners, accelerators, adhesion promoters. As a result many formulations tailored to the requirement of the end user can be achieved. These modifications are made to reduce costs, to improve performance, and to improve processing convenience. The applications for epoxy based materials are extensive and include coatings, adhesives and composite materials. Tremendous growth in the electronics market has markedly increased the demand for the epoxy resins for the manufacture of printed circuit boards and epoxy moulding compounds for semiconductor encapsulation. [0034] Lignin has been used as a phenol replacement in thermoset resin. Olivares, (1988), Wood Science and Technology, 22:15; Sarkar (2000), Journal of Adhesion Science and Technology, 14:1179; çetin (2002) Int. J. Adhesion and Adhesives 22:477; çetin (2003) Turk. J. Agric. For. 27:183-189; Sellers, (2004) For. Prod. J. 54:45. Phenolic adhesive (liquid or powder) has been formulated with lignin from various sources to replace from 20-80% of the phenol component, or as filler in the resin itself. The inclusion of lignin in resin formulations generally reduces the curing time and the cost of production of the resin, and yields a product with improved strength, water resistance, thermal stability and durability. [0035] The use of lignin to partially displace phenol in adhesive manufacture has also been successfully applied to the manufacture of friction products including automotive brake pads and mouldings. The preference for lignin, in the case of phenol-formaldehyde based adhesives, is also based on documented co-displacement of formaldehyde in addition to the reduction in emissions of toxic volatile organic compounds. Bisphenol A based epoxy adhesive has been modified by polyblending with lignin. [0036] Epoxy resin formulations containing at least 50% lignin exhibit acceptable physical and electrical properties for a wide range of applications. IBM developed epoxy/lignin resin formulation for the fabrication of printed wiring boards to reduce the environmental concerns with the fabrication, assembly, and disposal of this product. The laminates formed from lignin based resins are processed in a similar fashion to current laminates, minimizing the financial considerations of converting to this resin system. In one study, a comparison of the lignin-based resin and current resins through a life-cycle assessment indicated a 40% reduction in energy consumption for the lignochemical based resin. Isolated lignin of the present invention may be used in any and all of these applications. [0037] The disclosed lignin may also provide a polyol backbone for reaction to produce compositions such as polyurethane resins. In this application, the disclosed lignin may replace petrochemical-based polyol feedstocks currently used in the production of polyurethane resins. Polyols are compounds with multiple hydroxyl functional groups available for organic reactions. More than 75% of all the polyols produced globally are used in the manufacturing of polyurethane resin. The polyols provide the backbone structure of the PU resin and may be polyether, polyester, polyolefin or vegetable oil based; the first two being the most widely used. Polyether-based polyols are generally obtained from the base-catalyzed polymerization of cyclic ethers (propylene, ethylene and butylene oxides) to a hydroxyl or amine-containing initiator. Polyester polyols are generally produced by condensation of a diol (ethylene glycol, propylene glycol) and a dicarboxylic acid. Aromatic polyester polyols are generally derived from phthalic acid. A major cost in the production of polyols is attributed to the costs of propylene oxide. Propylene oxide (PO) is a liquid commodity chemical (derived from butane/isobutane, propylene, methanol and oxygen), used in the production of derivative products, including polyether polyols, propylene glycol, propylene glycol ethers and various other products. [0038] Polyether polyols are used for the formulation of polyurethane resin for manufacture of softer, elastic and more flexible products (spandex elastomeric fibers and soft rubber parts, as well as soft foam) used in automobile and recreational vehicle seats, carpet underlay, furniture upholstering, bedding, and packaging. Polyfunctional polyester polyols are largely used in the formulation of polyurethane resin used for the manufacture of more rigid products such as low density foams of high grade thermal insulation, or structural construction products. Polyurethane rigid foam has grown in use because of its combination of low heat transfer and cost effectiveness. Applications for polyester flexible urethane foam include gaskets, air filters, sound-absorbing elements, and clothing inter liners (laminated to a textile material). Generally, polyether-based foams have a greater hydrolysis resistance, are easier to process, and cost less. Polyester-based foams have a more uniform structure with higher mechanical properties and better oil and oxidative degradation resistance. Both types can be sprayed, moulded, foamed in place, or furnished in sheets cut from slab. [0039] Aromatic polyester polyol has become the polyol of choice for the formulation of rigid polyurethane foam. The use of aromatic polyester polyol in conjunction with polyurethane chemistry has counteracted the adverse effects of the flammability characteristic resulting from a change to non-CFC blowing agents. Polyester polyols provide superior mechanical properties, such as tensile strength, abrasion, and wear resistance, as well as solvent and oil resistance, to the polyurethanes in which they are used. With the phase-out of hydrochlorofluorocarbon blowing agents, polyester polyol producers are challenged to provide products to the polyurethane industry suitable for use with next generation blowing agents. New products must produce foams with an excellent balance of properties, and concurrently maintain cost-effectiveness and environmentally friendliness. [0040] Lignins, like polyols, have multiple aromatic and aliphatic hydroxyl functional groups making them reactive towards MDI or TDI (diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI)). With its aromatic ring, lignin can act as a flame retardant (like phthalic acid derived aromatic polyester polyol) in polyurethane applications. Lignin has been used to replace the polyol component of polyurethane resins, prepared by the polyaddition reaction of a difunctional isocyanate molecule to the hydroxyl groups of the polyol forming a series of block copolymers with alternating hard and soft phases. A whole spectrum of PU can be prepared from a wide range of polyols with different functionality and molecular weights and just a few types of di-isocyanate. One of the most desirable attributes of polyurethanes is their ability to be turned into foam by the addition of a blowing agent. Use of lignin in the rigid foam industry would improve both hydrolytic and UV resistance. Lignin of the present invention may be efficiently introduced in the formulation, for example, of polyurethane coatings, adhesives and foams. [0041] The isolated lignin disclosed herein may be used in any and all of these applications, for example, as a filler or to replace specific components in the formulation of plastics resins (such as phenols, epoxies, polyurethanes, polyvinyls, polyethylenes, polypropylenes, polystyrenes, polyimides, polycarbonates, formaldehydes, acrylics, acrylonitrile-butadiene-styrenes and alkyds-based), used in the manufacturing of thermoset or thermoplastic material such as adhesives, binders, coatings, films, foams, rubbers, elastomers, carbon fibers and composites. [0042] Polyvinyl chloride (PVC) is an extremely versatile material and can be converted into rigid products, and flexible articles when compounded with plasticizers. Unmodified PVC resin has very little utility due to poor physical properties and processability. PVC is almost always converted into a compound by the incorporation of additives such as plasticizers, heat stabilizers, light stabilizers, lubricants, processing aids, impact modifiers, fillers, flame retardants/smoke suppressors, and, optionally, pigments. Rigid PVC applications include pipes and fittings largely for water service; profiles for windows, doors, and siding; film and sheet for packaging and construction; and blow moulded containers for household and health and beauty products. Flexible PVC with high plasticizers loading is used in a variety of applications including film and sheet for packaging, coated fabrics for upholstery and wall coverings, floor coverings for institutional and home use (bathrooms and kitchens), tubing for medical and food/drink uses, and wire and cable insulation. [0043] The manufacture of PVC is generally expensive, and raw material costs are generally high. In addition, there is considerable PVC-related toxicity, including toxic and potentially endocrine-disrupting effects of various additives used in PVC compounds, use of chlorine with potential for atmospheric ozone depletion, formation of dioxin from incineration of PVC and possible leaching of hazardous materials following disposal of PVC. Partial replacement of PVC (20 parts) with different lignins is already feasible for some formulations that can be successfully used as matrices for a high level of calcium carbonate filler in flooring products. The introduction of the isolated lignin of the present invention in these types of materials will not only reduce the cost and environmental imprint of plastics made from these materials but will also produce plastics with a better resistance to UV, thermal, hydrolytic, oxidative and biological destabilization. [0044] Carbon fibers are generally used as long, thin strands of material about 0.005-0.010 mm in diameter, and composed mostly of carbon atoms. Several thousand carbon fibers are twisted together to form a yarn, which may be used itself, or woven into a fabric. The yarn or fabric may be combined with epoxy, for example, and wound or moulded into shapes to form various composite materials. [0045] Carbon fibers are generally made using a partly chemical and partly mechanical process. Acrylonitrile plastic is mixed with another plastic (such as methyl acrylate) and reacted with a catalyst. The precursor blend is then extruded into long fibers, and stretched to a desired diameter. The fibers must then be stabilized (via heating in air at low temperatures 200-300° C.), before carbonizing them (via heating in the absence of oxygen at high temperatures (e.g. 1000-3000° C.). The fibers undergo a surface oxidation to allow them to react more effectively with chemical and mechanical bonding. The final treatment is to coat the fibers (sizing) which protects them from damage in winding and weaving. The coated fibers are wound onto bobbins, and are referred to as a “tow” that can be twisted into yarns of various sizes. Carbon fibers are generally supplied by producers as a continuous fiber or as a chopped fiber. Carbon fibers may be combined with thermoset and thermoplastic resin systems and are mainly applied to reinforce polymers, much like glass fibers have been used for decades in fiber glass. They have many uses in specialty type industries like the aerospace industry, and automobile industry. [0046] The disclosed lignin may be used as a carbon skeleton suitable for manufacturing carbon fibers and carbon fiber compositions, and may replace synthetic polymers such as polyacrylonitrile (PAN) in the production of carbon fibers and carbon fiber compositions. [0047] The disclosed lignin moreover provides a superior feedstock that may be broken down to provide aromatic or repeated units that are useful as fine chemicals. In addition, the disclosed lignin may be used as a superior quality feedstock for thermodegradation to bio-oil, synthesis gas, char, or fine chemicals via hydrothermal treatment, gasification or pyrolysis. The high grade isolated lignin disclosed herein may also be employed as a plasticizer, as a UV stabilizer, as described, for example, in U.S. Pat. No. 5,939,089, or as a water repellent. [0048] In addition, because of its unique properties (molecular weight profile, chemical and molecular structures), the lignin disclosed herein can be employed in various applications to provide antioxidant, immunopotentiation, anti-mutagenic, anti-viral and/or anti-bacterial activity, and to improve the general health of animals or humans. [0049] Because the disclosed isolated lignin has a generally high reactivity and a generally low contaminant composition, higher ratios of the disclosed isolated lignin can be used as a feedstock for making many products requiring polymer feedstocks without deleteriously affecting the properties of the final product. As a result, the high grade isolated lignin disclosed herein may be employed in a wide range of products, leading to a reduction in the amount of fossil fuel carbon, toxic substances and non-biodegradable materials required to manufacture these products and thereby contributing to the efficient and sustainable use of resources. In addition, the high grade isolated lignin disclosed herein is a relatively inexpensive feedstock and drastically reduces the cost of materials such as carbon composites, epoxy-type resins, polyurethane and other products that otherwise require high cost, petrochemical-derived feedstocks. [0050] Processing of biomaterials using a modified ORGANOSOLV™ process that employs a low boiling solvent, preferably comprising ethanol, and substantially in the absence of an acid catalyst, also increases the recovery and integrity of xylan polymers. In a hot water treatment, either alone, or following a solvent extraction process, the xylan polymers are hydrolyzed, yielding their monomer units in the water hydrolysate. The xylose rich water hydrolysate provides another valuable product stream from which crystalline xylose, furfural and/or xylitol may be derived. The xylose rich water stream may also be used as a fermentation substrate for the production of ethanol, xylitol and other valuable fermentation products, providing additional valuable polymer feedstocks for use directly or for further processing. [0051] Xylose may thus also be produced using the processing methodology disclosed herein. Specifically, large quantities of the five carbon sugar xylose are released as a yellow liquor in a hot water washing of pulp, independently of or following lignin removal by solvent extraction. Currently, xylose-rich yellow liquors are generally produced by acid hydrolysis of birch wood, bagasse, rice husks, corn and wheat straw. Xylose, furfural, xylitol and other products of an extraction process (e.g., a hot water extraction process as disclosed herein), using the plant material feedstocks disclosed, herein are also contemplated as products of the present invention. [0052] Xylose is used for the production of furfural used in the formulation of industrial solvents. Xylose of the present invention may be used for the production of furfural, as well as directly, or in xylose-derived products, as a food or beverage additive in human, animal and other organism feeds. In addition, xylose of the present invention may be used as a feedstock for conversion (e.g., via hydrogenation) to xylitol, a sugar alcohol used as non-carcinogenic, low calorie sweetening compound. Xylose and concentrated xylose syrups and crystalline cellulose of the present invention are suitable for use as ingredients by food industries (human and animal, for example). The xylose-rich yellow liquor of the present invention may also be used without further processing as a fermentation substrate for the biochemical production of ethanol. In various aspects, products of the present invention include: the xylose-rich yellow liquor derived using the methods disclosed herein; xylose isolated from the yellow liquor; and yellow liquor and isolated xylose derived from hardwoods, including copiccable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein. [0053] Xylitol is used as a low calorie food sweetener. It is as sweet as sucrose, provides a cooling effect, has no after-taste, and is safe for diabetics as it is metabolized independently of insulin. It has 40% less calories than sugar and is the only sweetener to show both passive and active anti-caries effects. Xylitol is used in a wide range of applications in the food industry as a sugar substitute (e.g. in confectionery, gum and soda) and in the pharmaceutical and personal care industries (e.g. in oral hygiene products and cosmetic products). [0054] Xylitol is produced commercially by hydrogenation of xylose obtained from birch wood sulphite pulping liquor and other xylan-rich substrates. The production process involves the extraction and purification of xylose from the pulping liquor, a chemical hydrogenation reaction, and the recovery of xylitol by chromatographic methods. The chemical based conversion of xylans to xylitol is approximately 50-60% efficient. Alternative technology based on microbial reduction of xylose from xylan rich hydrolysate is considered to be ‘cleaner’ and generally requires less energy than the chemical conversion. The present invention contemplates xylitol produced by hydrogenation of xylose isolated from hardwoods, including coppicable shrubs such as Salix . In various aspects, products of the present invention include: xylitol produced using the xylose-rich yellow liquor derived using the methods disclosed herein; xylitol produced using xylose isolated from the yellow liquor; and xylitol produced using isolated xylose derived from hardwoods, including coppicable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein. [0055] Furfural is an aromatic aldehyde obtained by catalytic dehydration of a xylose concentrate solution. Furfural is an intermediate commodity chemical used in synthesizing a range of specialized chemical products, starting mainly with furfural alcohol (FFA), which also has many derivatives. Furfural is used in the production of resin (phenol, acetone, or urea based) used as a binding agent in foundry technologies or in the manufacture of composite for the aeronautic and automotive industries. Furfural is also used as a selective solvent in petroleum production of lubricants. There are many other uses (e.g. adhesive, flavoring and as a precursor for many specialty chemicals), but resins account for over 70 percent of the market. Furfural is highly regarded for its thermosetting properties, physical strength and corrosion resistance. Furfural is important in terms of its presence, as a carbohydrate, in a chemical industry dominated by hydrocarbons. [0056] In addition to providing a high quality xylose suitable for conversion to furfural, modified ORGANOSOLV™ treatment followed by hot water extraction provides a furfural-rich yellow liquor. In various aspects, products of the present invention include: furfural produced using the furfural-rich yellow liquor derived using the methods disclosed herein; and furfural derived from hardwoods, including coppicable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein. [0057] In yet other aspects, products of the present invention include celluloses, sugars (e.b., glucose), hemicelluloses, and downstream products produced using such products, including ethanol and other fermentation products derived from hardwoods, including coppicable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein. [0058] These and additional features of the present invention and the manner of obtaining them will become apparent, and the invention will be best understood, by reference to the following more detailed description and the accompanying drawings. BRIEF DESCRIPTION OF THE FIGURES [0059] FIG. 1 is a schematic of the first stage (ethanol extraction) of an integrated process for the production of biofuel and lignin from wood chips. [0060] FIG. 2 is a schematic of the second stage (hot water treatment) of an integrated process for the production of biofuel and lignin from wood chips. [0061] FIG. 3 is a schematic of the third stage (simultaneous saccharification and fermentation) of an integrated process for the production of biofuel and lignin from wood chips. [0062] FIG. 4 is a schematic of the fourth stage (product separation/purification) of an integrated process for the production of biofuel and lignin from wood chips. [0063] FIG. 5 is the 2D 13 C- 1 H correlation (HSQC) spectra of lignin side chain regions, acquired during NMR analysis of an isolated lignin sample described herein. [0064] FIG. 6 is the 2D 13 C- 1 H correlation (HSQC) spectra of side chain region, acquired during NMR analysis of a Kraft lignin (Sigma-Aldrich #370959) sample. [0065] FIG. 7 shows the volume integration of the 2D 13 C- 1 H correlation (HSQC) spectra of side aromatic units, acquired during NMR analysis of an isolated lignin sample described herein. [0066] FIG. 8 illustrates gel filtration elution profiles showing the molecular weight distribution of an isolated lignin sample of the present invention in FIG. 8A (BJL5), a commercial Kraft lignin (Sigma-Aldrich #370959) sample in FIG. 8B , and a commercial ORGANOSOLV lignin (Sigma-Aldrich, #37101-7) sample in FIG. 8C . DETAILED DESCRIPTION [0067] As discussed above, the present invention provides high grade isolated lignin polymers obtained from processing of plant materials, such as lignocellulosic plant materials. Ligocellulosic plant materials are harvested, air-dried and stockpiled. Reduction of the particle size of the harvested plant material may be desired prior to processing, and this can be achieved using a chipper or similar device to mechanically reduce the size of the plant material feedstock. Suitable size reduction techniques are well known in the art and one of ordinary skill in the art may readily determine appropriate particle sizes and size distributions for various types of feedstocks used in the present invention. [0068] In one solvent extraction methodology, the first stage of the process disclosed herein is a modified ORGANOSOLV™, or aqueous ethanol extraction (illustrated schematically in FIG. 1 ). In one embodiment, this involves continuously contacting a lignocellulosic plant material with a counter-current flow of an aqueous solution comprising up to 80% ethanol, undertaken at a temperature of approximately 170° C. to 210° C. and a pressure of 19-30 barg. In one embodiment, the digester is a screw contactor operating with wood chips being fed and discharged via cup and cone pressure plugs or feed screws. Solvent passes against the flow of solids so that plant material exiting the digester is exposed to fresh (solute free) ethanol solution, while chips entering the digester, which have the highest extractable content, are exposed to the most solute laden solvent solution. [0069] Solvent entering the digester may be pressure pumped to maintain the operating pressure therein and to provide the hydraulic drive to pass against the flow of chips. Solvent from within the digester is re-circulated through external heaters, for example steam heaters, on a continuous basis to bring the wood chips up to the operating temperature quickly and to maintain the temperature. Operating conditions (such as time, temperature profile, pressure and solids/liquid ratio) within the digester may be optimized to provide maximum removal of water insoluble lignin from the plant material. As the plant material exits the digester and is exposed to lower pressures, a portion of the solvent content therein evaporates, resulting in cooling of the treated plant material. In alternative embodiments, the plant material may be displaced in the digester using gravity in a downward gradient. Solvent entering the digester may be pumped against the flow of solids. Multiple solvent extraction stages may be provided. Lignin is solubilized in the aqueous ethanol solvent (“black liquor”) and may be isolated from the “black liquor” produced during solvent extraction. [0070] Plant material, or pulp, discharged from a solvent extraction stage of the process still contains some ethanol, which is preferably removed prior to a subsequent water extraction step. Solvent removal may be achieved by means of a steam stripping operation. The vapors recovered from both this operation and from other solvent recovery techniques, may be collected and re-used directly with the fresh solvent stream. In this way the latent heat content of the vapors is recovered. [0071] The de-solventized plant pulp material may optionally be processed in a second stage of extraction (illustrated schematically in FIG. 2 ), which may be undertaken in comparable equipment and in a comparable fashion to the ethanol extraction described above, with the difference being that high pressure hot water (preferably at a pressure of approximately 2 to 25 barg and a temperature of approximately 130° C. to 220° C.) is utilized to solubilize the hemicellulose sugars in the plant pulp material. As the solids exit the hot water digester and the pressure is reduced, flash evaporation of steam occurs. This may be recovered for direct re-use with the fresh hot water entering as fresh extraction solvent at the solids discharge end of the digester. The treated plant pulp is also cooled as a result of this flash evaporation. [0072] The non soluble constituents of the initial plant material that remain in the pulp after two stages of extraction (solvent and hot water) are primarily cellulose and other sugars present in the form of a hydrolyzable pulp. This material may be hydrolyzed to produce glucose. In one hydrolysis procedure, the hydrolyzable pulp is transferred to one of a series of batch SSF (simultaneous saccharification and fermentation) vessels, together with temperature-tolerant yeast, yeast growth media, cellulase, β-glucosidase, buffer and water to dilute the solids to the required solid/liquid ratio (illustrated schematically in FIG. 3 ). In these vessels, the cellulose is hydrolyzed to produce glucose, which is in turn fermented to produce ethanol. Low levels of ethanol are maintained in the fermentor by continuous removal of the produced ethanol to avoid fermentation inhibition. The process is optimized for maximum cellulose hydrolysis and fermentation to ethanol. The vessel contents at the end of the batch fermentation will be discharged via a filter and the retained solids will be disposed of, or recovered to be further processed to yield additional products. The filtrate, consisting primarily of ethanol and water, may be concentrated to produce hydrous and/or anhydrous ethanol as desired, using methods well known to those of skill in the art. A portion of the hydrous ethanol product may be re-utilized in the first, ethanol extraction stage. [0073] Products, such as high grade lignin, are separated and purified as illustrated schematically in FIG. 4 . In one embodiment, the black liquor (ethanol/water/lignin solution) exiting the solvent extraction digester in the first stage may be depressurized before passing to a flash cooling vessel in which the solvent is evaporated. Further ethanol may then be steam-stripped from the liquor prior to transfer to one of a series of batch vessels, in which precipitation of lignin from the liquor is promoted through dilution (generally from about 2 to 10 times, by volume) with water. The pH of the diluted black liquor may be reduced by acid addition to increase the lignin precipitation rate, if desired. After settling, the lignin sludge may be dewatered by filtration and/or centrifugation and dried to produce an isolated lignin product. [0074] Alternatively, the lignin solubilized in the black liquor may be recovered using a dissolved gas flotation (DAF-like) based process as described below. Because of its low cost, gentle recovery conditions and rapid recovery, the dissolved gas flotation method described herein is preferred for many lignin isolation and harvesting processes compared to conventional methods like settling and centrifuging and may be used to harvest lignin extracted from plant materials using a variety of extraction techniques. In this embodiment, after flash cooling, the black liquor may optionally be filtered and the solubilized lignin in an aqueous solvent solution is then mixed with a gasified aqueous solution (e.g., water). The gasified solution contains a high concentration of a gas such as air, nitrogen, CO 2 , mixtures thereof, and the like. The pressure and gas flow rates may be adjusted to provide desirable gas concentrations, properties, etc. in the lignin recovery vessel. [0075] Gasified aqueous solutions may be prepared, for example, by storing water in a pressure vessel under nitrogen, carbon dioxide or any other suitable gas at a pressure of at least 2 barg. The water level in the pressure vessel is regulated by the use of a float valve or similar device. Compressed air, nitrogen or carbon dioxide (such as CO 2 recovered from the fermentation process) may be admitted at the base of the tank, and the incoming gas may be passed through a sparger to increase the dissolution rate of the gas in the aqueous solution. The gasified solution is withdrawn from the pressure vessel through a metering valve which regulates its flow rate. As the gasified solution leaves the tank and is mixed with the black liquor, the decrease in pressure leads to the generation of many small gas bubbles (“microbubbles”) which attach to the hydrophobic lignin precipitate as it forms, and cause it to float to the surface. [0076] In one embodiment, (optionally filtered) black liquor comprising lignin solubilized in an aqueous solvent solution is pumped (using, for example, a metering pump) into a mixing device, such as a venturi mixer or a similar device. The mixing device preferably creates conditions of high fluid shear to provide rapid and complete mixing of the gasified water with the black liquor, and is preferably constructed from materials that minimize the amount of lignin adhering to the surfaces of the device. When the solubilized lignin is diluted in the aqueous solution, the hydrophobic lignin precipitates and forms immiscible particulates in the aqueous solution. Microbubbles of gas attach themselves to the immiscible lignin particles and transport them to the surface of the mixed solution. The floating lignin may then be separated by mechanical means. In one embodiment, the floating lignin particulates are pushed toward a conveyer belt by means of a paddle, for example. The conveyer belt may be constructed from a porous material, allowing partial dewatering of the lignin as it is harvested. The speed and length of the conveyer belt may be adjusted to provide optimum harvesting efficiency and lignin drying. It will be apparent to one of ordinary skill in the art that different types of lignin harvesting processes may also be used. After lignin removal, the ethanol may be separated from the water and recycled, while the aqueous fraction may be combined with a hot water stream for use in further processing, such as xylose and water soluble product recovery. [0077] The present invention further provides methods for recovering lignin from an aqueous suspension of lignin. In one embodiment, the lignin may be recovered from water washes by a process in which ammonium salts (e.g., 10 mM ammonium chloride or ammonium sulfate, but not ammonium bicarbonate) or low concentration detergents (e.g., 50 parts per million of Triton™ X-100 ((C 14 H 22 O(C 2 H 4 O)n) or Nonidet™ P40 (nonylphenyl-polyethylene glycol), but not Tween™ 80 (polyoxyethylene (20) sorbitan monooleate) or sodium dodecyl sulphate, are added to the solution. This causes the lignin suspended in the water washes to flocculate, facilitating harvesting of the washed lignin. The effects of detergents and ammonium salts are additive. The use of ammonium chloride to aid in the harvesting of washed lignin precipitates may be particularly advantageous, as ammonium chloride is volatile, and excess ammonium chloride can thus be easily removed from the harvested lignin during the drying process. Ethanol may also be used to recover the washed lignin. At low concentrations (for example less than 35% v/v), ethanol induces the precipitation of lignin from a water suspension. The use of ethanol in this process is particularly advantageous because it is volatile and can thus be easily removed from the harvested lignin during the drying process. [0078] Raw lignin material isolated from Salix viminalis or Salix schwerinii ‘Kinuyanagi’ using the process described above employing 70% aqueous ethanol at 185° C. for 60 minutes, and harvested by precipitation and centrifugation from the black liquor or using the dissolved gas flotation described above, was shown to have a high degree of similarity to natural lignin, to retain a high degree of reactivity and to be relatively pure, with a minimal amount of carbohydrate contamination. In preferred embodiments, isolated lignin preparations of the present invention comprise less than about 1.0% sugars; in some embodiments less than about 0.2% sugars and, in yet additional embodiments, less than about 0.5% sugars. In some embodiments, isolated lignin compositions of the present invention have a carbohydrate composition of less than about 0.2 g per liter supernatant detectable by HPLC using an ion exclusion column following hydrolysis of the lignin preparation with concentrated sulfuric acid. In addition, isolated lignin preparations of the present invention are substantially free from salts and particulate components. [0079] Isolated lignin having a relatively high ratio of syringyl (S) units is preferred for many applications. Lignin extracted from Salix viminalis or Salix schwerinii ‘Kinuyanagi,’ or a mixture of both species, with 70% ethanol at 185° C. for a retention time of 60 minutes and harvested by precipitation and centrifugation was composed of approximately 80% syringyl (S) units (ratio S:G of 4:1) and had a low degree of chemical modification with a high proportion of β-aryl-ether and resinol subunits. In some embodiments, isolated lignin compositions of the present invention have a syringyl unit content of at least about 50%, in some embodiments, of at least about 60%, in yet other embodiments, of at least about 70%, and in still other embodiments of at least about 80%. Isolated lignin compositions of the present invention preferably have an S:G ratio of at least about 2:1; more preferably at least about 3:1 and, even more preferably for some applications, at least about 4:1. [0080] Isolated lignin preparations made as described herein have an average molecular weight of about two to three times higher than comparative commercial Kraft and ORGANOSOLV lignin preparations, as demonstrated by the experimental evidence presented in Example 6, below. In some embodiments, isolated lignin compositions of the present invention have a weight average molecular mass (determined as described below) of at least about 4,000. In some embodiments, isolated lignin compositions disclosed herein have a weight average molecular mass (determined as described below) of at least about 4,500, and in yet other embodiments, the disclosed isolated lignin compositions have a weight average molecular mass (determined as described below) of at least about 5,000. In still other embodiments, isolated lignin compositions of the present invention have a weight average molecular mass (determined as described below) of at least about 5,500. [0081] The isolated lignin preparations also have relatively high numbers of reactive hydroxyl groups that are important to provide reactivity with other chemicals or polymers, as well as high numbers of methoxyl groups of 30 to 40 per 100 units. In addition, the high grade isolated lignin disclosed herein is minimally modified and therefore has a reactivity that is closer to that of natural (“native”) lignin. Isolated lignin compositions of the present invention generally comprise detectable quantities of at least three side chains selected from the group consisting of phenylcoumaran, resinol, α-ethoxy-β-aryl-ether, and cinnamyl alcohol side chains. According to some embodiments, isolated lignin compositions of the present invention comprise detectable quantities of phenylcoumaran, resinol, α-ethoxy-β-aryl-ether, and cinnamyl alcohol side chains. The side chains present in isolated lignin preparations may be detected and measured using nuclear magnetic resonance spectroscopy analysis, for example. [0082] High grade isolated lignin compositions of the present invention generally have a high ratio of β-aryl-ether subunits, generally at least about 40%, in some embodiments at least about 50%, and in yet other embodiments at least about 60%. High grade isolated lignin compositions of the present invention also have a generally high ratio of resinol subunits, generally at least about 6%, in some embodiments at least about 8%, and in yet other embodiments at least about 10%. [0083] Because of its purity, homogeneity and unique reactivity, the isolated lignin preparations obtained as described herein can be used without further processing. However, if desired, residual volatile compounds may be removed by heat treatment, and non-volatile residual compounds may be removed, for example, using a water wash. In some embodiments, the isolated, raw lignin may be recovered from a water suspension using a selective flocculation method as described herein. In some embodiments, the isolated lignin may be harvested from the black liquor using a dissolved gas flotation technique as described herein. [0084] The high grade isolated lignin disclosed herein is useful as a feedstock for a variety of downstream industrial processes and material manufacturing processes. In one embodiment, the high grade isolated lignin described herein can be melted or dry spun at a desired temperature and speed to produce carbon fibers using methods well known to those of skill in the art and including, but not limited to, those taught in U.S. Pat. Nos. 3,461,082 and 5,344,921. Because of its homogeneity, the disclosed lignin has the capacity to form regular, continuous filaments of carbon during extrusion. Also, because of the higher S unit ratio and lower condensation level, lignin prepared from Salix using the process described herein is stable during the thermostabilization of the carbon filament. If required, the spinning, extrusion and/or carbonization can be facilitated by blending the disclosed lignin with a plasticizer (for example polyvinyl alcohol (PVAL), polyethylene oxide (PEO) or polyester (PES)) or by condensation of lignin units following chemical modification of the lignin. The melting and extrusion of polycondensed high grade lignin or lignin polymer blend can also be useful for the production of composites and plastics. [0085] Superior lignin-based polyurethane (PU) can be formulated by using the disclosed lignin either directly as a polyol precursor or blended with other polyol types (for example, polyethylene glycol (PEG), polyethyleneadipate (PEA) and/or polypropylene glycol (PPG)) to react with an isocyanate radical of polyisocyanates or isocyanate-terminated polyurethane prepolymers either in the presence or absence of a catalyst. The efficient functionalization of the disclosed lignin with diisocyanates also allows, upon reaction with polyols, the formulation of a high quality PU resin. In addition, the disclosed lignin can be functionalized with an epoxide for further reaction with an isocyanate or added as filler to a prepared PU resin. PU resin prepared using the disclosed high grade lignin can be used as a lower cost, high quality, adhesive and/or coating, or can be easily cast and cured for the formation of high quality films. When water or a foaming agent is added to the formulation of the lignin based PU, foams of various density levels can be produced. [0086] Superior phenolic resins can also be formulated from the disclosed high grade lignin. Because of its higher reactivity compared to Kraft and sulfite lignins, the disclosed lignin will provide a superior replacement of phenol in many phenol based resins used in a wide variety of applications, ranging from adhesives to composites. The disclosed high grade lignin can be either directly blended with the phenol resin or incorporated into the resin at high ratios by condensation or derivatization with phenol or formaldehyde. The disclosed lignin may thus be used to produce a safe and biodegradable resin. [0087] The natural properties of the high grade lignin disclosed herein can be modified by polymer blending. The lignin is able to form proper hydrogen bonding for miscible blend formation with plasticizing agents such as polyethylene oxide (PEO), polyethylene terephthalate (PET), polyvinyl pyrrolidone (PVP), polyvinyl chloride (PVC), polyvinyl acetate (PVA), polyethene-co-vinylacetate (EVA), polypropylene (PP), polyethylene (PE) and others, allowing further control of its thermal processability. This can be useful, for example, to facilitate the spinning, extrusion and/or casting of the lignin-based final product, or in the making of adhesives, paints coatings, plastics and the like. The stronger intermolecular interaction between polymers and the disclosed high grade lignin will create superior lignin-polymer blends with a positive impact on the derived composite. [0088] The viscoelastic properties of lignin can also be altered and modified through chemical introduction of unsaturated carbonyl groups or nitrogen-containing compounds. Another advantage of the unique properties of the disclosed high grade lignin is the efficiency and lower cost of chemical conversion of its phenol, alkene or hydroxyl moieties into other functional groups. The disclosed lignin is more amenable to alkylation and dealkylation, oxyalkylation (for example, oxypropylation, for production of polyoxyalkylene polyethers), amination, carboxylation, acylation, halogenation, nitration, hydrogenolysis, methylolation, oxidation, reduction, polymerization, sulfomethylation, sulfonation, silylation, phosphorylation, nitroxide formation, grafting and composite formation. In general, such lignin modifications are inefficient and costly due to the presence of impurities, heterogeneity and high level of altered moieties in the conventional lignin preparations. These modifications can be performed more efficiently and at lower cost on the disclosed high grade lignin to produce useful polymeric materials. [0089] Reactive epoxy functionality can be added at lower cost to the disclosed high grade lignin than with conventional lignin preparations. The disclosed lignin can be directly reacted with ethylene-unsaturated groups or hydroxypropyl groups to prepare a lignin-based epoxide with good solubility that may be used in co-polymerization reactions. The disclosed lignin is also a superior substrate for conversion into polyols by propoxylation (reaction with propylene oxide such as 2-methyloxirane) or ethoxylation (reaction with ethylenoxide such as oxirane) chain extension reaction. Epoxide-lignin resin may be cured to a hard infusible plastic and may also be reacted with fatty acids to produce resins for paints and inks or may be reacted with various amines to produce polyamines or polyamides for use as adhesives or plastics. Epoxidized high grade lignin may also be employed to reduce the need for polyol in PU resin and for displacement of phenol epoxy resin. [0090] The following examples are offered by way of illustration and not by way of limitation. Example 1 Recovery of Lignin from Salix Preparation and Composition Analysis of Untreated Salix Biomass [0091] Stems of Salix viminalis or Salix schwerinii ‘Kinuyanagi’ were chipped with a garden mulcher. The wood chips were dried at 40° C. for 24 hours and sieved by hand between two wire meshes of British test sieve with apertures of 2.8 and 4 mm. The composition of the sieved and unsieved Salix chips was assessed, with the results being shown in Table 1. The mass composition was assessed using laboratory analytical procedures (LAPs) developed by the National Renewable Energy Laboratory (NREL, Golden, Colo.). Values are expressed as gram of component per 100 g of dry untreated chips. Extractives were isolated using a Soxhlet extractor, dried and weighed. Lignin concentrations were determined after chemical hydrolysis of the Salix chips (4 hours with 72% sulfuric acid at 102° C.). Acid soluble lignin was measured by densitometry at 320 nm and the concentration of the non-acid soluble lignin was measured by weight minus ash. The percentage of glucan and xylan present in the samples were determined after chemical hydrolysis (4 hours with 72% sulfuric acid at 102° C.). Acid soluble sugar was measured by HPLC using the appropriate range of xylose and glucose standards. The composition of the untreated Salix material was determined and is shown below in Table 1. [0000] TABLE 1 Composition of untreated Salix biomass (*= Sieved material) Ex- trac- tive Lignin (%) Sugar (%) Salix variety (%) Soluble Insoluble Total Glucan Xylan Salix viminalis * 16 2 31 33 23 9 Salix viminalis 8 3 24 27 34 8 Salix schwerinii 6 5 23 28 32 14 Salix schwerinii 4 5 22 27 33 12 Kinuyanagi Salix schwerinii 4 3 25 28 33 9 Kinuyanagi Salix schwerinii 2 4 28 32 35 9 Kinuyanagi + Salix viminalis Salix schwerinii 2 4 25 29 30 8 Kinuyanagi + Salix viminalis Average 6 4 25 29 31 10 Standard 5 1 3 3 4 2 Deviation Pre-Treatment of Salix Biomass [0092] A modified ORGANOSOLV™ treatment of Salix chips was tested in 100 ml experimental digester and 3 l packed-bed experimental digester that were able to process 6 g and 300 g of dry wood chips, respectively. The design of these two digesters is illustrated in and described with reference to FIG. 5 (100 ml digester) and FIG. 6 (3 l packed-bed digester) of U.S. Patent Publication US 2007/0259412 A1. A 40 l digester was also designed and tested for the recovery of natural lignin from Salix biomass at larger scale (shown in and described with reference to FIG. 7 of U.S. Patent Publication US 2007/0259412 A1). The 40 l digester processed 6 kg of dry biomass. Process conditions for solvent treatment of the Salix chips and subsequent hot water treatment of the plant pulp material recovered from the solvent treatment are also described in U.S. Patent Publication US 2007/0259412 A1. Lignin from the 100 ml and 3 l digesters was harvested by precipitation and centrifugation as described in U.S. Patent Publication US 2007/0259412 A1. Lignin from the 40 liter digester was harvested by precipitation and centrifugation and, in some instances, by dissolved air flotation techniques described herein. [0093] At all scales (100 ml, 3 l packed-bed, and 40 l batch), sequential solvent extraction using an aqueous solution comprising 70% ethanol followed by hot water treatment resulted in the removal of over 30% of the total lignin content of the untreated chips. The majority of the lignin (28 to 32%) was solubilized during the solvent extraction using the 70% ethanol aqueous solution, and an additional 3 to 8% of the total lignin was removed during the subsequent hot water treatment. [0094] The ratio of lignin to DM removed by the 70% ethanol treatment reached 35% in the first hour of treatment retention time at a temperature of 170° C. to 190° C. using the 100 ml and the 3 l packed-bed digesters. The lignin composition of the DM removed in the 3 l packed-bed digester during the second hour of treatment retention time increased by 5% and reached 50% after 4 hours. After 8 hours retention time in the reactor, the lignin content of the DM removed increased only by another 10% to reach 60%. In the 40 l batch digester, the ratio of lignin to DM removed varied from 30 to 48% when Salix dry chips were treated with 70% ethanol solvent. The proportion of the total lignin content in the untreated chips that was recovered in the 70% ethanol solvent using each of the three digesters varied over time. The high recovery of total lignin (32%±3) in 60 minutes using the smaller 100 ml digester reflected the higher rate of DM removal achieved with this digester. With the 3 l packed-bed digester, similar recovery was achieved within 200 to 240 minutes of treatment retention time. The amount of total lignin recovered using the 40 l batch digester varied between 22 and 44% of the initial lignin content of the Salix chips, corresponding to 6 to 13% of the initial DM loaded. Example 2 Harvesting Precipitated Lignin by Dissolved Air Flotation [0095] Lignin was precipitated from black liquor, and the precipitate harvested using a dissolved gas (air) flotation technique (“DAF”), as follows. Water was supersaturated with nitrogen by storage under elevated nitrogen pressure (2 barg) for at least 30 minutes. The water was allowed to leave the pressure vessel through a metering valve which regulated the flow rate of aerated water at 26 ml/min. Filtered black liquor (containing 12.4 g of lignin per liter) was pumped from the black liquor tank at various flow rates using a peristaltic pump. The aerated water and black liquor were mixed in a venturi mixing device and delivered into a flotation tank. Upon rapid mixing with the gassified water, the lignin in the black liquor precipitated, flocculated and floated to the surface of the tank. The supernatant passed under a dam and overflowed out of the tank. Based on the tank volume and the liquid flow rates, the residence time of the precipitate in the tank was calculated to be about three minutes. A paddle wheel device was used to move the lignin precipitate to one end of the precipitation tank. A porous moving belt of nylon mesh was used to lift the precipitated lignin out of the tank and drain off the supernatant liquid. A Perspex scraper was used to harvest the lignin from the belt and allow it to fall into the collection tank. [0096] The relative flow rates of the aerated water and black liquor were varied, and the best yields of precipitated lignin were obtained where the water flow rate was at least three times the black liquor flow rate. Various venturi mixing devices were tested, and the best devices were found to be those which delivered the black liquor into the venturi through a small nozzle having a diameter of approximately 0.2 mm. This provided black liquor linear velocities of about 5 msec, implying that high shear rates are important to give good mixing. The venturi throat which gave best mixing had a diameter of 1 mm, which would give a linear flow rate for the mixture of 0.7 msec. [0097] Use of the optimal conditions detailed above gave a lignin harvesting yield of 89% of theoretical. A further 3.6% of the lignin yield remained in suspension, and floated to the surface of the supernatant at later times. This suggests that a longer residence time of the precipitate in the tank would give a higher yield. The lignin sludge harvested from the belt was found to contain 4% w/v lignin. Pressing the sludge between two pieces of filter paper increased the lignin concentration to 20% w/v. This indicates that a belt press or similar device could be used to increase the solids content of the lignin sludge, and consequently facilitate drying of the sludge. After air-drying, the lignin harvested by the DAF technique disclosed herein yielded a light brown powder containing about 10% moisture. [0098] The precipitation was found to occur optimally at a temperature of about 20° C. Temperatures above 35° C. gave a dense, sticky precipitate in poor yield. Example 3 Large-Scale Harvesting of Lignin by DAF [0099] Lignin was precipitated from black liquor, and the precipitate harvested by dissolved gas (air) flotation, on a larger scale as follows. Water was supersaturated with air by storage under compressed air pressure (2 barg). The water was allowed to leave the pressure vessel through a metering valve which regulated the flow rate of aerated water at 4.5 l/min. Filtered black liquor (containing 14.8 g of lignin per liter) was pumped from the black liquor tank at 1.4 l/min using a peristaltic pump, and the aerated water and black liquor were mixed in a venturi mixing device and delivered into a flotation tank. (The mixing ratio of aerated water to black liquor was 3.2:1) The venturi jet had a diameter of 2.5 mm, which would yield a black liquor linear velocity of 1.2 msec. The venturi throat had a diameter of 7 mm, implying a linear velocity for the mixture of 2.6 msec. The lignin in the black liquor precipitated, flocculated and floated to the surface of the tank. When the tank was full the floating lignin was allowed to stand for 30 mins and then harvested manually with a plastic scoop. The solids content of the lignin sludge varied in repeated experiments from 6-14% lignin w/v. The sludge was placed in a porous fabric bag and allowed to drain overnight. This typically increased the lignin solids content to about 23% w/v. The lignin sludge was then air-dried and sieved to yield a light brown powder containing about 10% moisture. Example 4 Flocculation of an Aqueous Lignin Suspension [0100] The ability of various additives to cause flocculation of lignin in an aqueous suspension of lignin was examined. The results of these studies are provided in Table 2, below. [0000] TABLE 2 Flocculation of lignin Additive Concentration suspension Ammonium 2 mM − chloride 4 mM − 20 mM ++ 40 mM ++ 80 mM ++ 200 mM ++ 400 mM ++ Nonidet ™ 0.4 ppm − P40 1 ppm − 4 ppm − 12 ppm + 37 ppm ++ 111 ppm ++ 333 ppm ++ 1,000 ppm ++ Ethanol 1% v/v − 2% v/v + 4% v/v + 9% v/v ++ 12% v/v ++ 17% v/v ++ 29% v/v ++ 38% v/v + 44% v/v * 50% v/v * ++: Flocculation +: Partial flocculation −: No flocculation * Clear solution (precipitate dissolved) [0101] Ammonium chloride at concentrations between 20 mM and 400 mM caused the lignin suspension to flocculate. Concentrations of greater than 400 mM were not tested. Ammonium sulfate and ammonium bicarbonate were also tested for their ability to cause flocculation of the lignin suspension. Ammonium sulfate gave similar results to ammonium chloride while ammonium bicarbonate had a weak effect at 400 mM and no effect at lower concentrations. Nonidet™ P40 at concentrations between 37 ppm and 1,000 ppm caused the lignin suspension to flocculate, with a weak effect being seen at 12 ppm and no effect at lower concentrations. Concentrations of greater than 1,000 ppm were not tested. Triton™ X-100 and Triton™ X-114 gave similar results to Nonidet™ P40. Sodium deoxycholate showed a weak effect at 1,000 ppm and no effect at lower concentrations. No effect was shown with sodium dodecyl sulfate, Tween™ 20, Tween™ 80, α-methyl mannoside, Brij™ 76, Brij™ 700, Lubrol™ PX or cetyltrimethylammonium bromide (CTAB). [0102] Ethanol at concentrations between 29 and 9% v/v caused the lignin suspension to flocculate. At ethanol concentrations of 4% and 2% there was a weak effect, with no effect being seen at a concentration of 1% v/v. Ethanol at 38% v/v and higher caused the lignin precipitate to dissolve. Example 5 Properties of Lignin Isolated from Salix as Determined by NMR [0103] The lignin preparation submitted for NMR analysis was isolated by the treatment of 6.54 g (dry weight) of Salix schwerinii ‘Kinuyanagi’ dry chips with an aqueous solvent comprising 70% ethanol at 190° C. for 100 minutes in the 100 ml digester. The lignin recovered from the black liquor by precipitation and centrifugation was dissolved in DMSO-d6 for nuclear magnetic resonance spectroscopy analysis (as described in Ralph et al., 2006, Journal of Biological chemistry 281(13):8843) and compared to a commercially available Kraft lignin preparation (Sigma-Aldrich #370959). The 2D spectra of the lignin side chains from the NMR analysis for the Salix lignin isolated using the methodology described herein is shown in FIG. 5 , and the 2D spectra of the lignin side chains from the NMR analysis for a commercial Kraft lignin preparation is shown in FIG. 6 . [0104] FIG. 5 illustrates the distribution of lignin side chains, including β-aryl ether (identified as “A”), phenylcoumaran (identified as “B”), resinol (identified as “C”), α-ethoxy-β-aryl ether (identified as A2) and cinnamyl alcohol side chains (identified as X1) retained in the lignin isolated using the modified ORGANOSOLV™ process described herein. FIG. 6 illustrates that minute quantities of β-aryl ether (identified as “A”) were present in the isolated Kraft lignin preparation, while there were no detectable quantities of phenylcoumaran, resinol, α-ethoxy-β-aryl ether or cinnamyl alcohol side chains. The lignin subunit distribution was quantified via volume-integration of the 2D contours in HSQC spectra, with minor corrections. The high ratio of β-aryl-ether (73%) and resinol (12%) subunits in the high grade isolated lignin preparation described herein is indicative of a higher degree of conservation of native structure. The destruction of the lignin side chains that occurs during Kraft pulping is shown by the absence of signal in the NMR spectra ( FIG. 6 ) indicating the presence of the native lignin side chains in the commercial Kraft lignin sample. These results demonstrate that lignin isolated using the methodology described herein retains a more “natural” structure than commercially available Kraft lignin, with the retention of a large proportion of the side chain structures that are important for lignin reactivity. [0105] The lignin isolated according to methods described herein also demonstrated a higher methoxyl content than the commercially available Kraft lignin (30 to 40% as determined by volume-integration of the 2D contours in HSQC spectra, FIG. 5 ), making it desirably less likely to re-condense and more amenable toward chemical reaction. [0106] The spectra shown in FIGS. 5 and 6 identify unresolved or unknown (non-lignin) components, such as saccharides, as “U.” These unresolved and unassigned constituents are contaminants in a lignin preparation. It is evident from the spectra illustrated in FIGS. 5 and 6 that the commercially available Kraft lignin preparation is highly impure and has a high level of contamination, while the lignin preparation of the present invention has considerably fewer contaminants. In fact, nearly all of the material detected in the commercially available Kraft lignin preparation is contaminant material. While contaminants are present in the lignin preparation of the present invention ( FIG. 5 ), those contaminants represent a far less significant proportion of the preparation. [0107] Additionally, no sugars were detectable when the disclosed isolated lignin preparation was hydrolysed with concentrated sulfuric acid and the supernatant analysed by HPLC (High pressure liquid chromatography) on an ion exclusion column (BioRad Phenomenex Rezex™) with a lower detection limit of 0.2 g of sugars (glucose or xylose) per litre. [0108] Lignin isolated from Salix schwerinii ‘Kinuyanagi’ using the above process was composed of about 80% syringyl (S) units and a ratio of syringyl:guaiacyl units of about 4:1 as quantified by volume integration of the 2D contours in HSQC spectra ( FIG. 7 ). This high ratio of S lignin is also reflected by the relatively high content of O-methoxyl groups (40%, FIG. 5 ). Example 6 Additional Properties of Lignin Isolated from Salix [0109] The molecular weight average and molecular weight distribution of several samples of the disclosed high grade isolated lignin were calculated from the gel filtration elution profile of the lignin preparation ( FIG. 8 ) on a Superdex Peptide column (GE Healthcare #17-5176-01 10/300 GL, as described by Reid (1991), Biotechnol. Tech, 5:215-218). Lysozyme, aprotinin and 3,4-dimethylbenzyl alcohol were used as standards for calibration and therefore these molecular weights should be taken as relative values. Isolated lignin samples were prepared as described above using lignin harvested by precipitation and centrifugation (Samples BJL2-5) and lignin harvested using the DAF process described herein (Sample BJLD) were dissolved at 0.5 mg/ml in 50% ethanol/50 mM NaOH for the gel filtration analysis. Commercially available lignin samples were prepared for comparative analysis, including a Kraft lignin preparation (Sigma-Aldrich #370959) and an ORGANOSOLV lignin preparation (Sigma-Aldrich, cat. No. 37, 101-7). Each sample was analysed in duplicate with an injection volume of 200 μl. The results are shown in FIG. 8 and summarized in Table 3, below. [0110] The majority of the lignin (at the elution peak) in the isolated lignin samples prepared as disclosed herein and harvested by precipitation and centrifugation (samples BJL2-5), had an average molecular mass of approximately 6,500 g/mol. This molecular mass is about 2 to 3 times greater than the molecular mass of the majority of the lignin (at the elution peak) in the commercially available Kraft lignin composition (Sigma-Aldrich #370959; molecular mass 1,942 g/mol) or the commercially available ORGANOSOLV lignin composition (Sigma-Aldrich, cat. No. 37, 101-7; molecular mass 2,627 g/mol). The weight average molecular mass of the isolated lignin samples BJL2-5 was in excess of 5,200, while the weight average molecular mass of the commercial Kraft lignin preparation was approximately 2,229 and the weight average molecular mass of the commercial ORGANOSOLV lignin preparation was approximately 3,000. These values are in agreement with previously published studies using gel filtration for molecular weight analysis of Kraft and ORGANOSOLV lignin preparations from hardwood (Kubo and Kadla (2004) Macromolecules, 37:6904-6911; Cetin and Ozmen (2002) Proceedings of ICNP ; Glasser et al. (1992) J. Wood Chem. and Technol. 13:4, 545-559), with slightly higher polydispersity (PD) values. The isolated lignin sample prepared as disclosed herein and harvested using the DAF process described here (Sample BJLD) had an average molecular mass of over 7,200 and a weight average molecular mass of over 5,500. [0000] TABLE 3 Molecular Mass g/mol at elution peak Weight Poly- (n = 2) Average dispersity Lignin Sample Avr StDv (Mw) (PD) BJL2 5,933 0.668 4,871 4.1 BJL3 6,374 0.844 5,384 3.0 BJL4 6,800 0.810 5,372 3.9 BJL5 7,172 0.285 5,450 3.9 BJL Average 6,570 0.535 5,269 3.7 BJLD 7,271 0.049 5,712 3.7 Kraft 1,942 0.218 2,229 3.5 ORGANOSOLV 2,627 0.070 2,992 3.3 Example 7 Reactivity of High Grade Lignin Isolated from Salix [0111] The reactivity of the disclosed lignin was assessed by measurement of the total and phenolic hydroxyl groups and compared with the commercial Kraft and ORGANOSOLV lignin preparations (Table 4, below). The total amount of hydroxyl functional group in each lignin sample is expressed as a potassium hydroxide equivalent and was measured using standard testing method (ASTM D4274-05). The amount of phenolic hydroxyl groups in each lignin sample was assessed by differential spectrophotometry as described by Wexler (Analytical Chemistry 36(1) 213-221 (1964)) using 4-hydroxy-3-methoxybenzyl alcohol as a calibration standard. In this analysis, the amount of phenolic hydroxyl is relatively low for all the lignin samples analysis and the total amount of hydroxyl measurements do not vary greatly among the samples (Table 4). However, the ratio of phenolic to total hydroxyl is lower in the disclosed lignin samples (BJL2, BJL-5 and BJLD) as compared with the Kraft and ORGANOSOLV commercial lignin preparations. [0000] TABLE 4 Hydroxyl Numbers mmol/g Ratio Lignin Sample Total Phenolic Phenolic:Total BJL2 6.06 0.33 0.054 BJL5 6.23 0.28 0.044 BJLD 5.40 0.29 0.054 ORGANOSOLV 5.78 0.38 0.066 Kraft 6.41 0.40 0.062 Example 8 Production of Urethane Foam Using Isolated Lignin of the Present Invention [0112] Rigid polyurethane (PU) foam was produced using lignin derived from Salix and isolated as described herein. The foam was tested and demonstrated excellent thermal conductivity and density properties. The density of the rigid PU foam produced using isolated lignin was 0.62 g/cm 3 compared to a density of rigid PU foam produced using conventional feedstocks of 0.05 g/cm 3 . The thermal conductivity of the rigid PU foam produced using isolated lignin was 0.030 to 0.032 compared to a thermal conductivity of rigid PU foam produced using conventional feedstocks of 0.035. The thermal degradation temperature of the rigid PU foam produced using isolated lignin was 295° C.; the compression strength was 0.5 MPa; and the compression modulus was 19 MPa. [0113] While the present invention has been described with reference to the specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, method, method step or steps, for use in practicing the present invention. All such modifications are intended to be within the scope of the claims appended hereto. [0114] To the extent that the claims appended hereto express inventions in language different from that used in other portions of the specification, applicants expressly intend for the claims appended hereto to form part of the specification and the written description of the invention, and for the inventions, as expressed in the claims appended hereto, to form a part of this disclosure. [0115] All of the publications, patent applications and patents cited in this application are herein incorporated by reference in their entirety to the same extent as if each individual publication, patent application or patent was specifically and individually indicated to be incorporated by reference in its entirety.
Lignin polymers having distinctive properties, including a generally high molecular weight and generally homogeneous size distribution, as well as preservation of native reactive side groups, are isolated by solvent extraction of plant materials. Methods for isolation of lignin polymers, and for use of the isolated lignin polymers are disclosed. Compositions containing lignin isolated from plant materials, such as carbon fiber composites, resins, adhesive binders and coatings, polyurethane-based foams, rubbers and elastomers, plastics, films, paints, nutritional supplements, food and beverage additives are disclosed. Xylose and xylose derivatives, furfural, fermentable sugars, cellulose and hemi-cellulose products may be used directly or further processed. The lignin polymers and other plant-derived products disclosed herein may be produced in abundance at low cost, and may be used as substitutes for feedstocks originating from fossil fuel or petrochemical sources in the manufacture of various products.
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[ "REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser.", "No. 12/203,047, filed Sep. 2, 2008, which claims priority to U.S. Provisional Patent Application Nos. 60/969,452 filed Aug. 31, 2007 and 61/083,839 filed Jul. 25, 2008, and to PCT International Patent Application PCT/NZ2008/000225 filed Sep. 1, 2008, and is a continuation-in-part of U.S. patent application Ser.", "No. 11/745,993 filed May 8, 2007, now U.S. Pat. No. 7,649,086, which claims priority to U.S. Provisional Patent Application Nos. 60/746,682 filed May 8, 2006 and 60/869,057 filed Dec. 7, 2006.", "FIELD OF THE INVENTION [0002] The present invention relates to lignin and other products, such as xylose, xylitol, furfural, fermentable sugars, cellulose and hemi-cellulose products isolated from plant materials, methods for isolating such products from plant materials, and compositions containing such plant-derived products.", "BACKGROUND [0003] Mounting global energy demands have dramatically increased the cost of fossil-fuel-based energy sources and petrochemicals.", "And, the environment has been harmed, perhaps irreparably, in an effort to meet this demand by discovery and extraction of fossil-fuel feedstocks, and by processing of those raw feedstocks to produce ever increasing amounts of fuel, petrochemicals, and the like.", "Petrochemicals furthermore provide the majority of raw materials used in many plastics and chemical industries.", "The present invention is directed to providing isolated, plant-derived, renewable and sustainable compositions that have multiple utilities and that provide renewable and sustainable substitutes for fossil-fuel derived and petrochemical feedstocks.", "[0004] Lignin is a complex, high molecular weight polymer that occurs naturally in plant materials, and is one of the most abundant renewable raw materials available on earth.", "Lignin is present in all vascular plants and constitutes from about a quarter to a third of the dry mass of wood.", "It is covalently linked to hemicellulose in plant cell walls, thereby crosslinking a variety of plant polysaccharides.", "Lignin is characterized by relatively high strength, rigidity, impact strength and high resistance to ultra-violet light and, in wood, has a high degree of heterogeneity, lacking a defined primary structure.", "[0005] Lignin molecules are generally large, cross-linked macromolecules and may have molecular masses in excess of 10,000 in their native form in plant material.", "The degree of lignin polymerization in nature is difficult to determine, since lignin is fragmented during extraction.", "Various types of lignin have been characterized and described, with the lignin properties generally depending on the extraction methodology.", "There are three monolignol monomers, which are methoxylated to various degrees: p-coumaryl alcohol, coniferyl alcohol, and synapyl alcohol.", "These monomers are incorporated in lignin polymers in the form of phenylpropanoids p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S).", "Different plants exhibit different proportions of the phenylpropanoids.", "[0006] The polyphenolic nature of lignin and its low toxicity, together with many additional properties (such as its dispersing, binding, complexing and emulsifying, thermal stability, specific UV-absorbing, water repellent and conductivity characteristics), make it an attractive renewable replacement for toxic and expensive fossil fuel-derived polymer feedstocks.", "Unlike synthetic polymers, lignin is biodegradable in nature.", "In spite of its biodegradability, lignin is known to be one of the most durable biopolymers available.", "[0007] Large quantities of lignin are produced as a by-product of the pulp and paper industry.", "Despite its unique and desirable characteristics as a natural product with multiple beneficial chemical, physical and biological properties, and its abundance, lignin isolated from plant materials remains largely under-exploited.", "The heterogeneity and low reactivity of lignin recovered from waste effluent produced by the pulp and paper industry has resulted in limited industrial utilization of this highly abundant and renewable natural product.", "[0008] Lignin is recovered from sulfite or Kraft wood pulping processes as lignosulfonates containing significant amounts of contaminants.", "The recovered lignin molecules lack stereoregularity, with repeating units being heterogeneous and complex.", "In general, lignin obtained as a by-product of the Kraft process (referred to as Kraft lignin) requires further processing and/or modification, as described in U.S. Pat. Nos. 5,866,642 and 5,202,403, in order to increase its reactivity and to allow its use in the formation of higher value products.", "Kraft lignin preparations contain a mixture of lignin sulfonate and degraded lignin, together with numerous decomposition products, such as sugars, free sulfurous acid and sulfates.", "The phenolic structures of the Kraft lignin are highly modified and condensed.", "The sulfite process for wood treatment produces a water soluble sulfonated lignin preparation that contains a high content of sugars, sugar acids and sugar degradation products, as well as resinous extractives and organic constituents with multiple coordination sites.", "The costs associated with the purification and functionalization required to make these low grade lignin preparations useful have limited their utilization in high value application markets.", "[0009] The use of organic solvents for lignin extraction prior to carbohydrate hydrolysis as disclosed, for example, in U.S. Pat. Nos. 4,764,596, 5,788,812 and 5,010,156, was shown to improve the quality of the resulting lignin, but the use of a catalyst in combination with various types of solvents under severe conditions often produced lignin having altered reactivity (McDonough (1992) TAPPI Solvent Pulping Seminar, Boston, Mass.", ", The Institute of Paper Science and Technology ;", "Pan and Sano (2000) Holzforschung 54:61-65;", "Oliet et al.", "(2001) J. Wood Chem.", "Technol.", "21:81-95;", "Xu et al.", "(2006) Industrial Crops and Products 23:180-193).", "[0010] The reactivity of lignin depends mainly on the presence and frequency of aliphatic, phenolic hydroxyl and carbonyl groups, which varies depending on the lignin source and the extraction process used to obtain the lignin.", "The average molecular weight and polydispersity of lignin in the preparation also has a great impact on its reactivity.", "[0011] As demonstrated in the many attempts to replace phenol with lignin in the formation of phenol-based resins, the low reactivity of the lignin means that only a small amount of phenol can be displaced without affecting the mechanical and physical properties of the final resin (çetin and Özmen (2002) Int.", "J. Adhesion and Adhesives 22:477-480;", "çetin and Özmen (2003) Turk.", "J. Agric.", "For.", "27:183-189;", "Sellers et al.", "(2004) For.", "Prod.", "J. 54:45-51).", "Similar difficulties are encountered when lignin is employed in other types of applications.", "For example, the thermostability of lignin used to produce carbon fibers by spinning, as described in U.S. Pat. No. 6,765,028, and the carbonization of the resulting lignin fibers, are largely influenced by the method of lignin extraction and the origin and composition of the lignin (Kadla et al.", "(2002) Carbon 40:2913-2920).", "[0012] When acidic ethanol-extracted lignin was used as a polyol for the experimental preparation of polyurethane (PU), replacement of 35% to 50% of the PU resin was achieved without compromising the integrity of the lignin-based PU film (Vanderlaan and Thring (1998) Biomass and Bioenergy 14:525-531;", "Ni and Thring (2003) Int.", "J. Polymeric Materials 52:685-707).", "Smaller ratios of replacement of PU resin (<10%) have been achieved by direct blending of soda lignin in pre-formed PU resin (Ciobanu et al.", "(2004) Industrial Crops and Products 20:231-241).", "[0013] Polymer blending is also a convenient method to develop lignin based products with desirable properties.", "(See, e.g., Kubo and Kadla (2003) Biomacromolecules 4(3):561-567;", "Feldman et al.", "(2003) J. Appl.", "Polym.", "Sci.", "89:2000-2010;", "Alexy et al.", "(2004) J. Appl.", "Polym.", "Sci.", "94:1855-1860;", "Banu et al.", "(2006) J. Appl.", "Polym.", "Sci.", "101:2732-2748) The efficiency and quality of the polymer blend is normally closely related to the chemical and physical properties of the lignin preparation, such as monomer type(s), molecular weight and distribution, which depends on the origin of the lignin and method used for its extraction, isolation and harvesting.", "[0014] Upgrading lignin through chemical functionalization has been shown to be a good strategy for the successful incorporation of plant-derived lignins in high value products.", "However, these reactions are costly when low grade or low reactivity lignin is used as the substrate for chemical modification.", "Large amounts of reactants are required, together with longer reaction times and higher temperatures, to achieve relatively low rates of transformation of low grade and low reactivity lignins.", "This adds to the cost of the lignin feedstock and reduces its desirability for use in various types of industrial processes.", "SUMMARY OF THE INVENTION [0015] In one aspect, the present invention provides isolated, high grade lignin polymers derived from plant materials, as well as methods for isolating lignin from plant materials, compositions comprising the high grade lignin polymers and methods for using such lignin polymers in high value products.", "The disclosed lignin is more suitable for use as a feedstock for making downstream products than lignin extracted from plant materials using alternative methods, such as acid or alkaline extraction or steam explosion techniques, and has distinct properties compared to lignin polymers isolated from plant materials using alternative techniques.", "[0016] The plant material employed in the disclosed methods for producing a high grade isolated lignin product is preferably a lignocellulosic plant material selected from the group consisting of: woody or herbaceous materials, agricultural and/or forestry plant materials and residues, and dedicated energy crops.", "In some embodiments, the plant material comprises a hardwood material, and in some embodiments the plant material comprises a coppicable hardwood material, such as a coppicable shrub.", "In certain embodiments, the plant material employed comprises a material selected from a group consisting of Salix (e.g., Salix schwerinii, Salix viminalis ), Poplar, Eucalyptus , Mesquite, Jatropha, Pine, switch grass, miscanthus, sugar cane bagasse, soybean stover, corn stover, rice straw and husks, cotton husks, barley straw, wheat straw, corn fiberwood fiber, oil palm (e.g., Elaeis guineensis, Eiaeis oleifera ) frond, trunk, empty fruit-bunch, kernels, fruit fibers, shell and residues of oil palm materials, and combinations thereof.", "Additional plant materials may be used.", "The present invention contemplates isolated lignin and other extraction products derived from any of these materials, and downstream products comprising lignin and other extraction products derived from any of these materials.", "[0017] In some embodiments, plant materials comprising a higher proportion of syringyl (S)-lignin compared to guaiacyl (G)-lignin are preferred for processing to recover high grade isolated lignin.", "Plant materials having a S:G lignin ratio of at least 1:1 are preferred for some applications;", "plant materials having a S:G lignin ratio of at least 2:1 are preferred for some applications;", "and plant materials having a S:G lignin ratio of at least 3:1 or about 4:1 are preferred for some applications.", "The present invention comprehends isolated lignin and other extraction products derived from such plant materials, as well as compositions comprising isolated lignin and other extraction products derived from such plant materials.", "[0018] In one aspect, high grade lignin and other extraction products may be isolated as a product of a solvent extraction process for treating plant materials such as the process disclosed in U.S. patent application Ser.", "No. 11/745,993, filed May 8, 2007 and published Nov. 8, 2007 as US 2007/0259412 A1, the disclosure of which is hereby incorporated by reference in its entirety.", "In this aspect, lignin is isolated from a plant material in a modified ORGANOSOLV™ (aqueous ethanol solvent) extraction process that involves contacting the plant material with a solution comprising up to about 70% ethanol in water at a temperature of approximately 170° C. to 210° C. and a pressure of from about 19-30 barg for a retention time sufficient to produce a “black liquor”", "solution containing lignin soluble in the aqueous ethanol solvent.", "In another aspect, lignin may be isolated from a plant material in a modified ORGANOSOLV™ (aqueous ethanol solvent) extraction process that involves contacting the plant material with a solution comprising up to about 80% ethanol in water, in some circumstances using a solution comprising from about 60% to about 80% ethanol in water, under conditions similar to those described above.", "[0019] The modified ORGANOSOLV™ extraction is preferably carried out substantially in the absence of an introduced acid catalyst.", "For example, the reaction mixture may contain less than 1% of an introduced acid catalyst and, according to some embodiments, the reaction mixture contains less than 0.5% of an introduced acid catalyst.", "In some embodiments, the modified ORGANOSOLV™ extraction process is carried out in the absence of an introduced acid catalyst.", "[0020] The black liquor produced using a modified ORGANOSOLV™ extraction process as described above may be flash evaporated to remove some of the solvent, and additional solvent may be steam-stripped from the liquor.", "The lignin may then be precipitated, separated by filtration and/or centrifugation, and dried.", "As a consequence of the mild nature of the modified ORGANOSOLV™ extraction process (treatment with aqueous ethanol solvent in the substantial absence of a biocatalyst), the extracted lignin is minimally modified from its native form and contains fewer contaminants (e.g., salts, sugars and/or degradation products) than lignins produced using Kraft or sulfite processes.", "The lignin produced by the modified ORGANOSOLV™ extraction process thus offers much greater potential as a bio-based feedstock material for use in a variety of processes and syntheses than lignin produced during paper pulp production or from other biomass fractionation processes using catalysts and more severe extraction conditions.", "[0021] High grade lignin of the present invention may thus be isolated from a plant material in a modified ORGANOSOLV™ extraction process that involves contacting the plant material with a solvent comprising up to 80% ethanol in water, in some embodiments from about 60% to 80% ethanol in water and, in some embodiments, about 70% ethanol in water.", "The temperature of the materials undergoing the modified ORGANOSOLV™ extraction process may be approximately 170° C. to 210° C., in some embodiments approximately 180° to 200° C., and in yet other embodiments approximately 185° to 195° C. The pressure in the reaction chamber during modified ORGANOSOLV™ processing is generally from about 19-30 barg.", "For any given solvent composition, desired temperatures during modified ORGANOSOLV™ processing produce pressures that substantially prevent the solvent from boiling.", "[0022] According to some embodiments, the solvent extraction is carried out on a substantially continuous processing basis, in a reaction vessel that provides co-current or countercurrent flow of solvent and biomass feedstock.", "The modified ORGANOSOLV™ process, as described herein, particularly employing continuous processing, reduces the re-condensation and re-deposition of lignin often seen in batch reactors by allowing removal of solvent at temperatures well above the normal boiling point of the solvent.", "Alternatively, the solvent extraction may be carried out as a batch reaction or, according to some embodiments, as a batch reaction repeated two or more times.", "The solids:liquid ratio during solvent extraction is preferably at least 1:1 and, in some embodiments may be at least 1:2, in some embodiments at least 1:3;", "and in yet additional embodiments up to about 1:4.", "[0023] Residence time of the plant material in the reaction chamber, or solvent extraction digester, is generally at least about 20 minutes and may be from about 20 to 80 minutes.", "In alternative embodiments, the residence time may be from about 30 to 70 minutes or, in yet other embodiments, from about 40 to 60 minutes.", "A residence time in the solvent extraction digester sufficient to produce a “black liquor”", "solution containing lignin soluble in the aqueous ethanol solvent is suitable.", "The modified ORGANOSOLV™ extraction is preferably carried out substantially in the absence of an acid or alkaline catalyst.", "For example, the reaction mixture may contain less than 1% of an introduced acid or alkaline catalyst and, according to some embodiments, the reaction mixture contains no introduced acid or alkaline catalyst.", "[0024] In certain embodiments, the modified ORGANOSOLV™ extraction is carried out at a pH (measured with a glass electrode at room temperature) in the range of from about 3 to 9.5.", "In yet other embodiments, the modified ORGANOSOLV™ extraction is carried out at a pH of more than about 4 and less than about 8 and, in still other embodiments, the modified ORGANOSOLV™ extraction is carried out at a pH of more than about 5 and less than about 7.", "[0025] In another embodiment, a hot water treatment may be used alone, or in combination with (e.g., following) a solvent extraction process, to extract additional lignin from plant material, and/or from a plant pulp material recovered following solvent extraction.", "Suitable hot water treatments may involve contacting the plant or pulp material with an aqueous solution (e.g., water) at an elevated temperature (e.g. from about 130° C. and 220° C.) and at an elevated a pressure (e.g. from about 2-25 barg) for a retention time sufficient to remove hemicellulose sugars from the plant and/or plant pulp material, and then separating the aqueous solution from the treated solids and harvesting isolated lignin from the aqueous solution to produce a high grade lignin product.", "[0026] Water-soluble sugars such as xylose, as well as acetic acid and/or furfural may also be recovered from the aqueous hot water treatment solution.", "The resulting plant pulp material may be further processed to hydrolyze cellulose present in the plant material to glucose.", "This further processing may, for example, involve saccarification and/or fermentation.", "In one embodiment, the resulting plant pulp material is contacted with: (i) an aqueous solution comprising cellulase, β-glucosidase and temperature-tolerant yeast, (ii) yeast growth media, and (iii) buffer to hydrolyze cellulose present in the plant pulp material to glucose, which in turn may be fermented to produce ethanol.", "[0027] Lignin extracted from plant materials in a solvent extraction process as described above may be isolated and harvested, for example, by depressurizing the black liquor removed from the solvent extraction process, and removing the solvent (using, e.g., flash cooling, steam stripping, and similar processes), followed by precipitation of lignin.", "Precipitation of isolated lignin may be accomplished, for example, by dilution of the solvent mixture (generally from about 2 to 10 times, by volume) with an aqueous solution such as water and, optionally, by lowering the pH to less than about 3 by addition of acid.", "Addition of acid is generally not required, or the requirements are minimal, for harvesting lignin extracted from Salix and other hardwoods, but acid addition may be desirable for precipitation of lignin derived from other plant materials.", "In general, the use of hydrochloric acid is preferred to the use of other mineral acids if acid addition is desirable for precipitating lignin.", "This may desirably reduce the formation of condensation reaction products during processing.", "The isolated lignin precipitate may be harvested by filtration or centrifugation or settling, and dried.", "[0028] Alternatively, lignin extracted from plant materials in a solvent extraction and/or a hot water process and solubilized in an aqueous solvent solution may be isolated, for example, using a dissolved-gas-flotation process (e.g., “DAF-like process”).", "The solubilized lignin and solvent solution (e.g., black liquor) is generally cooled and may optionally be filtered, and is then mixed with a gasified solution.", "The gasified solution is generally an aqueous solution such as water.", "The volume of gasified solution is preferably from about 2 to 10 times that of the lignin solvent solution.", "In one embodiment, black liquor may be introduced into a mixing device that provides conditions of generally high fluid shear to provide rapid and substantially complete mixing of gasified solution with the black liquor.", "The gasified solution may be supersaturated, for example, with a gas such as CO 2 , nitrogen, air, or a gas mixture.", "During mixing with the aqueous solution, the hydrophobic lignin precipitates and is immiscible in the aqueous solution.", "Gas bubbles attach to the precipitated lignin and transport the precipitated lignin to the surface of the vessel, where it may be harvested using a DAF clarifier or by physical removal of the precipitated, buoyant lignin particulates.", "This lignin separation technique is an effective and gentle processing technique for recovering high grade lignin isolated from plant material using solvent extraction techniques, and may additionally be used to isolate lignin extracted from plant material using other techniques for extracting lignin from plant materials.", "Lignin separation and harvesting using a dissolved-gas-flotation technique may be carried out on either a batch basis or a continuous or semi-continuous processing basis.", "[0029] In another aspect, methods for recovering lignin from an aqueous suspension of lignin are provided.", "These methods may be useful in recovering lignin which has been precipitated from an aqueous ethanol solution by dilution, and the precipitate subsequently washed in water.", "Such methods include adding at least one component selected from the group consisting of: ethanol at a concentration of less than 40% v/v;", "ammonium salts other than ammonium bicarbonate;", "and detergents other than Tween™ 80 or sodium dodecyl sulphate.", "This causes the lignin to flocculate, whereby the lignin may be readily harvested from the suspension.", "In certain embodiments, ethanol is added at a concentration of between about 2% and 38% v/v, for example at a concentration of about 9% to about 29% v/v.", "The ammonium salt may, for example, be ammonium sulfate or ammonium chloride, and may be added at a concentration greater than 4 mM.", "Detergents that may be effectively employed in such methods include, but are not limited to, Triton™ X-100, Triton™ X-114 and Nonidet™ P40.", "In one embodiment the detergent is added at a concentration greater than 4 ppm.", "This method can be useful for desalting any type of lignin preparation, to separate lignin from unreacted product and/or to selectively recover lignin sub-fractions for specific applications.", "[0030] Because of its superior quality and its distinctive properties and structure, the high grade isolated lignin disclosed herein may be preferred over lignin isolated using different methodologies in the formulation of lignin-containing materials.", "The high grade lignin disclosed herein may be introduced, for example, in a variety of carbon based materials to provide products having an equivalent or higher quality than those produced using fossil fuel-derived raw materials or feedstocks, or other plant-derived lignins.", "Because of its superior blending capacity, the high grade isolated lignin disclosed herein may also be introduced in generally high proportions in a variety of resins used in the formulation of adhesives, films, plastics, paints, coatings and foams.", "The disclosed isolated lignin is also suitably reactive with other materials containing cross-linkable functional groups and amenable to chemical modification, resulting in increased reactivity.", "In general, shorter reaction times are required, and lower amounts of reactant are used and lost in processing isolated lignin of the present invention, resulting in cost reduction and more efficient chemical lignin modification.", "Also, as a consequence of its substantial homogeneity and purity, the thermal degradation of the isolated lignin disclosed herein generally yields a less complex mixture of products that may be upgraded or purified in further processing.", "[0031] Isolated lignin of the present invention, derived from renewable and sustainable plant sources may be used, in many applications, as a substitute for petrochemicals and fossil fuel derived materials that are currently used as raw materials in the plastics and chemical industries.", "As a consequence of its distinctive structural properties, substantial homogeneity and composition, isolated lignin disclosed herein may be used, for example, as a renewable and sustainable phenol biopolymer for synthesizing phenolic and epoxy resins, providing a substitute feedstock for the petrochemical-based phenol polymers that are currently used as feedstocks for synthesizing phenolic and epoxy resins.", "[0032] Phenolic resins encompass a variety of products formed by the reaction of phenol and aldehydes.", "Phenolic resin based adhesive acts as a matrix for binding together various substrates, including wood, paper, fibers (e.g., fiberglass), and particles (e.g., wood flour, foundry sand, etc.), to form cross-linked composites.", "Other aromatic hydrocarbons used in these reactions include cresols, xylenols, and substituted phenols.", "The aldehydes are usually formaldehyde, paraformaldehyde and/or furfural.", "Various other additives and reinforcing compositions may also be used to provide resins and end-use materials having a variety of properties.", "[0033] Epoxy resins, like phenolic resins, are liquid or solid resins which cure to form hard, insoluble, chemical resistant plastics.", "Resins derived from bisphenol-A are among the most widely used epoxy resins.", "Bisphenol A is produced by liquid-phase condensation of phenol with acetone (a by-product of phenol synthesis).", "The chemistry of epoxy resin and the range of commercially available variations allow cured polymers to be produced with a very broad range of properties.", "The exceptional adhesion performance of epoxy resin is due to the presence of polar hydroxyl and ether groups in the backbone structure of the resin.", "Epoxy resins are also known for their chemical and heat resistance properties.", "There are many ways of modifying epoxy resins: for example, addition of fillers, flexibilizers, viscosity reducers, colorants, thickeners, accelerators, adhesion promoters.", "As a result many formulations tailored to the requirement of the end user can be achieved.", "These modifications are made to reduce costs, to improve performance, and to improve processing convenience.", "The applications for epoxy based materials are extensive and include coatings, adhesives and composite materials.", "Tremendous growth in the electronics market has markedly increased the demand for the epoxy resins for the manufacture of printed circuit boards and epoxy moulding compounds for semiconductor encapsulation.", "[0034] Lignin has been used as a phenol replacement in thermoset resin.", "Olivares, (1988), Wood Science and Technology, 22:15;", "Sarkar (2000), Journal of Adhesion Science and Technology, 14:1179;", "çetin (2002) Int.", "J. Adhesion and Adhesives 22:477;", "çetin (2003) Turk.", "J. Agric.", "For.", "27:183-189;", "Sellers, (2004) For.", "Prod.", "J. 54:45.", "Phenolic adhesive (liquid or powder) has been formulated with lignin from various sources to replace from 20-80% of the phenol component, or as filler in the resin itself.", "The inclusion of lignin in resin formulations generally reduces the curing time and the cost of production of the resin, and yields a product with improved strength, water resistance, thermal stability and durability.", "[0035] The use of lignin to partially displace phenol in adhesive manufacture has also been successfully applied to the manufacture of friction products including automotive brake pads and mouldings.", "The preference for lignin, in the case of phenol-formaldehyde based adhesives, is also based on documented co-displacement of formaldehyde in addition to the reduction in emissions of toxic volatile organic compounds.", "Bisphenol A based epoxy adhesive has been modified by polyblending with lignin.", "[0036] Epoxy resin formulations containing at least 50% lignin exhibit acceptable physical and electrical properties for a wide range of applications.", "IBM developed epoxy/lignin resin formulation for the fabrication of printed wiring boards to reduce the environmental concerns with the fabrication, assembly, and disposal of this product.", "The laminates formed from lignin based resins are processed in a similar fashion to current laminates, minimizing the financial considerations of converting to this resin system.", "In one study, a comparison of the lignin-based resin and current resins through a life-cycle assessment indicated a 40% reduction in energy consumption for the lignochemical based resin.", "Isolated lignin of the present invention may be used in any and all of these applications.", "[0037] The disclosed lignin may also provide a polyol backbone for reaction to produce compositions such as polyurethane resins.", "In this application, the disclosed lignin may replace petrochemical-based polyol feedstocks currently used in the production of polyurethane resins.", "Polyols are compounds with multiple hydroxyl functional groups available for organic reactions.", "More than 75% of all the polyols produced globally are used in the manufacturing of polyurethane resin.", "The polyols provide the backbone structure of the PU resin and may be polyether, polyester, polyolefin or vegetable oil based;", "the first two being the most widely used.", "Polyether-based polyols are generally obtained from the base-catalyzed polymerization of cyclic ethers (propylene, ethylene and butylene oxides) to a hydroxyl or amine-containing initiator.", "Polyester polyols are generally produced by condensation of a diol (ethylene glycol, propylene glycol) and a dicarboxylic acid.", "Aromatic polyester polyols are generally derived from phthalic acid.", "A major cost in the production of polyols is attributed to the costs of propylene oxide.", "Propylene oxide (PO) is a liquid commodity chemical (derived from butane/isobutane, propylene, methanol and oxygen), used in the production of derivative products, including polyether polyols, propylene glycol, propylene glycol ethers and various other products.", "[0038] Polyether polyols are used for the formulation of polyurethane resin for manufacture of softer, elastic and more flexible products (spandex elastomeric fibers and soft rubber parts, as well as soft foam) used in automobile and recreational vehicle seats, carpet underlay, furniture upholstering, bedding, and packaging.", "Polyfunctional polyester polyols are largely used in the formulation of polyurethane resin used for the manufacture of more rigid products such as low density foams of high grade thermal insulation, or structural construction products.", "Polyurethane rigid foam has grown in use because of its combination of low heat transfer and cost effectiveness.", "Applications for polyester flexible urethane foam include gaskets, air filters, sound-absorbing elements, and clothing inter liners (laminated to a textile material).", "Generally, polyether-based foams have a greater hydrolysis resistance, are easier to process, and cost less.", "Polyester-based foams have a more uniform structure with higher mechanical properties and better oil and oxidative degradation resistance.", "Both types can be sprayed, moulded, foamed in place, or furnished in sheets cut from slab.", "[0039] Aromatic polyester polyol has become the polyol of choice for the formulation of rigid polyurethane foam.", "The use of aromatic polyester polyol in conjunction with polyurethane chemistry has counteracted the adverse effects of the flammability characteristic resulting from a change to non-CFC blowing agents.", "Polyester polyols provide superior mechanical properties, such as tensile strength, abrasion, and wear resistance, as well as solvent and oil resistance, to the polyurethanes in which they are used.", "With the phase-out of hydrochlorofluorocarbon blowing agents, polyester polyol producers are challenged to provide products to the polyurethane industry suitable for use with next generation blowing agents.", "New products must produce foams with an excellent balance of properties, and concurrently maintain cost-effectiveness and environmentally friendliness.", "[0040] Lignins, like polyols, have multiple aromatic and aliphatic hydroxyl functional groups making them reactive towards MDI or TDI (diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI)).", "With its aromatic ring, lignin can act as a flame retardant (like phthalic acid derived aromatic polyester polyol) in polyurethane applications.", "Lignin has been used to replace the polyol component of polyurethane resins, prepared by the polyaddition reaction of a difunctional isocyanate molecule to the hydroxyl groups of the polyol forming a series of block copolymers with alternating hard and soft phases.", "A whole spectrum of PU can be prepared from a wide range of polyols with different functionality and molecular weights and just a few types of di-isocyanate.", "One of the most desirable attributes of polyurethanes is their ability to be turned into foam by the addition of a blowing agent.", "Use of lignin in the rigid foam industry would improve both hydrolytic and UV resistance.", "Lignin of the present invention may be efficiently introduced in the formulation, for example, of polyurethane coatings, adhesives and foams.", "[0041] The isolated lignin disclosed herein may be used in any and all of these applications, for example, as a filler or to replace specific components in the formulation of plastics resins (such as phenols, epoxies, polyurethanes, polyvinyls, polyethylenes, polypropylenes, polystyrenes, polyimides, polycarbonates, formaldehydes, acrylics, acrylonitrile-butadiene-styrenes and alkyds-based), used in the manufacturing of thermoset or thermoplastic material such as adhesives, binders, coatings, films, foams, rubbers, elastomers, carbon fibers and composites.", "[0042] Polyvinyl chloride (PVC) is an extremely versatile material and can be converted into rigid products, and flexible articles when compounded with plasticizers.", "Unmodified PVC resin has very little utility due to poor physical properties and processability.", "PVC is almost always converted into a compound by the incorporation of additives such as plasticizers, heat stabilizers, light stabilizers, lubricants, processing aids, impact modifiers, fillers, flame retardants/smoke suppressors, and, optionally, pigments.", "Rigid PVC applications include pipes and fittings largely for water service;", "profiles for windows, doors, and siding;", "film and sheet for packaging and construction;", "and blow moulded containers for household and health and beauty products.", "Flexible PVC with high plasticizers loading is used in a variety of applications including film and sheet for packaging, coated fabrics for upholstery and wall coverings, floor coverings for institutional and home use (bathrooms and kitchens), tubing for medical and food/drink uses, and wire and cable insulation.", "[0043] The manufacture of PVC is generally expensive, and raw material costs are generally high.", "In addition, there is considerable PVC-related toxicity, including toxic and potentially endocrine-disrupting effects of various additives used in PVC compounds, use of chlorine with potential for atmospheric ozone depletion, formation of dioxin from incineration of PVC and possible leaching of hazardous materials following disposal of PVC.", "Partial replacement of PVC (20 parts) with different lignins is already feasible for some formulations that can be successfully used as matrices for a high level of calcium carbonate filler in flooring products.", "The introduction of the isolated lignin of the present invention in these types of materials will not only reduce the cost and environmental imprint of plastics made from these materials but will also produce plastics with a better resistance to UV, thermal, hydrolytic, oxidative and biological destabilization.", "[0044] Carbon fibers are generally used as long, thin strands of material about 0.005-0.010 mm in diameter, and composed mostly of carbon atoms.", "Several thousand carbon fibers are twisted together to form a yarn, which may be used itself, or woven into a fabric.", "The yarn or fabric may be combined with epoxy, for example, and wound or moulded into shapes to form various composite materials.", "[0045] Carbon fibers are generally made using a partly chemical and partly mechanical process.", "Acrylonitrile plastic is mixed with another plastic (such as methyl acrylate) and reacted with a catalyst.", "The precursor blend is then extruded into long fibers, and stretched to a desired diameter.", "The fibers must then be stabilized (via heating in air at low temperatures 200-300° C.), before carbonizing them (via heating in the absence of oxygen at high temperatures (e.g. 1000-3000° C.).", "The fibers undergo a surface oxidation to allow them to react more effectively with chemical and mechanical bonding.", "The final treatment is to coat the fibers (sizing) which protects them from damage in winding and weaving.", "The coated fibers are wound onto bobbins, and are referred to as a “tow”", "that can be twisted into yarns of various sizes.", "Carbon fibers are generally supplied by producers as a continuous fiber or as a chopped fiber.", "Carbon fibers may be combined with thermoset and thermoplastic resin systems and are mainly applied to reinforce polymers, much like glass fibers have been used for decades in fiber glass.", "They have many uses in specialty type industries like the aerospace industry, and automobile industry.", "[0046] The disclosed lignin may be used as a carbon skeleton suitable for manufacturing carbon fibers and carbon fiber compositions, and may replace synthetic polymers such as polyacrylonitrile (PAN) in the production of carbon fibers and carbon fiber compositions.", "[0047] The disclosed lignin moreover provides a superior feedstock that may be broken down to provide aromatic or repeated units that are useful as fine chemicals.", "In addition, the disclosed lignin may be used as a superior quality feedstock for thermodegradation to bio-oil, synthesis gas, char, or fine chemicals via hydrothermal treatment, gasification or pyrolysis.", "The high grade isolated lignin disclosed herein may also be employed as a plasticizer, as a UV stabilizer, as described, for example, in U.S. Pat. No. 5,939,089, or as a water repellent.", "[0048] In addition, because of its unique properties (molecular weight profile, chemical and molecular structures), the lignin disclosed herein can be employed in various applications to provide antioxidant, immunopotentiation, anti-mutagenic, anti-viral and/or anti-bacterial activity, and to improve the general health of animals or humans.", "[0049] Because the disclosed isolated lignin has a generally high reactivity and a generally low contaminant composition, higher ratios of the disclosed isolated lignin can be used as a feedstock for making many products requiring polymer feedstocks without deleteriously affecting the properties of the final product.", "As a result, the high grade isolated lignin disclosed herein may be employed in a wide range of products, leading to a reduction in the amount of fossil fuel carbon, toxic substances and non-biodegradable materials required to manufacture these products and thereby contributing to the efficient and sustainable use of resources.", "In addition, the high grade isolated lignin disclosed herein is a relatively inexpensive feedstock and drastically reduces the cost of materials such as carbon composites, epoxy-type resins, polyurethane and other products that otherwise require high cost, petrochemical-derived feedstocks.", "[0050] Processing of biomaterials using a modified ORGANOSOLV™ process that employs a low boiling solvent, preferably comprising ethanol, and substantially in the absence of an acid catalyst, also increases the recovery and integrity of xylan polymers.", "In a hot water treatment, either alone, or following a solvent extraction process, the xylan polymers are hydrolyzed, yielding their monomer units in the water hydrolysate.", "The xylose rich water hydrolysate provides another valuable product stream from which crystalline xylose, furfural and/or xylitol may be derived.", "The xylose rich water stream may also be used as a fermentation substrate for the production of ethanol, xylitol and other valuable fermentation products, providing additional valuable polymer feedstocks for use directly or for further processing.", "[0051] Xylose may thus also be produced using the processing methodology disclosed herein.", "Specifically, large quantities of the five carbon sugar xylose are released as a yellow liquor in a hot water washing of pulp, independently of or following lignin removal by solvent extraction.", "Currently, xylose-rich yellow liquors are generally produced by acid hydrolysis of birch wood, bagasse, rice husks, corn and wheat straw.", "Xylose, furfural, xylitol and other products of an extraction process (e.g., a hot water extraction process as disclosed herein), using the plant material feedstocks disclosed, herein are also contemplated as products of the present invention.", "[0052] Xylose is used for the production of furfural used in the formulation of industrial solvents.", "Xylose of the present invention may be used for the production of furfural, as well as directly, or in xylose-derived products, as a food or beverage additive in human, animal and other organism feeds.", "In addition, xylose of the present invention may be used as a feedstock for conversion (e.g., via hydrogenation) to xylitol, a sugar alcohol used as non-carcinogenic, low calorie sweetening compound.", "Xylose and concentrated xylose syrups and crystalline cellulose of the present invention are suitable for use as ingredients by food industries (human and animal, for example).", "The xylose-rich yellow liquor of the present invention may also be used without further processing as a fermentation substrate for the biochemical production of ethanol.", "In various aspects, products of the present invention include: the xylose-rich yellow liquor derived using the methods disclosed herein;", "xylose isolated from the yellow liquor;", "and yellow liquor and isolated xylose derived from hardwoods, including copiccable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein.", "[0053] Xylitol is used as a low calorie food sweetener.", "It is as sweet as sucrose, provides a cooling effect, has no after-taste, and is safe for diabetics as it is metabolized independently of insulin.", "It has 40% less calories than sugar and is the only sweetener to show both passive and active anti-caries effects.", "Xylitol is used in a wide range of applications in the food industry as a sugar substitute (e.g. in confectionery, gum and soda) and in the pharmaceutical and personal care industries (e.g. in oral hygiene products and cosmetic products).", "[0054] Xylitol is produced commercially by hydrogenation of xylose obtained from birch wood sulphite pulping liquor and other xylan-rich substrates.", "The production process involves the extraction and purification of xylose from the pulping liquor, a chemical hydrogenation reaction, and the recovery of xylitol by chromatographic methods.", "The chemical based conversion of xylans to xylitol is approximately 50-60% efficient.", "Alternative technology based on microbial reduction of xylose from xylan rich hydrolysate is considered to be ‘cleaner’ and generally requires less energy than the chemical conversion.", "The present invention contemplates xylitol produced by hydrogenation of xylose isolated from hardwoods, including coppicable shrubs such as Salix .", "In various aspects, products of the present invention include: xylitol produced using the xylose-rich yellow liquor derived using the methods disclosed herein;", "xylitol produced using xylose isolated from the yellow liquor;", "and xylitol produced using isolated xylose derived from hardwoods, including coppicable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein.", "[0055] Furfural is an aromatic aldehyde obtained by catalytic dehydration of a xylose concentrate solution.", "Furfural is an intermediate commodity chemical used in synthesizing a range of specialized chemical products, starting mainly with furfural alcohol (FFA), which also has many derivatives.", "Furfural is used in the production of resin (phenol, acetone, or urea based) used as a binding agent in foundry technologies or in the manufacture of composite for the aeronautic and automotive industries.", "Furfural is also used as a selective solvent in petroleum production of lubricants.", "There are many other uses (e.g. adhesive, flavoring and as a precursor for many specialty chemicals), but resins account for over 70 percent of the market.", "Furfural is highly regarded for its thermosetting properties, physical strength and corrosion resistance.", "Furfural is important in terms of its presence, as a carbohydrate, in a chemical industry dominated by hydrocarbons.", "[0056] In addition to providing a high quality xylose suitable for conversion to furfural, modified ORGANOSOLV™ treatment followed by hot water extraction provides a furfural-rich yellow liquor.", "In various aspects, products of the present invention include: furfural produced using the furfural-rich yellow liquor derived using the methods disclosed herein;", "and furfural derived from hardwoods, including coppicable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein.", "[0057] In yet other aspects, products of the present invention include celluloses, sugars (e.b., glucose), hemicelluloses, and downstream products produced using such products, including ethanol and other fermentation products derived from hardwoods, including coppicable hardwoods such as Salix , as well as from the other plant material raw materials disclosed herein.", "[0058] These and additional features of the present invention and the manner of obtaining them will become apparent, and the invention will be best understood, by reference to the following more detailed description and the accompanying drawings.", "BRIEF DESCRIPTION OF THE FIGURES [0059] FIG. 1 is a schematic of the first stage (ethanol extraction) of an integrated process for the production of biofuel and lignin from wood chips.", "[0060] FIG. 2 is a schematic of the second stage (hot water treatment) of an integrated process for the production of biofuel and lignin from wood chips.", "[0061] FIG. 3 is a schematic of the third stage (simultaneous saccharification and fermentation) of an integrated process for the production of biofuel and lignin from wood chips.", "[0062] FIG. 4 is a schematic of the fourth stage (product separation/purification) of an integrated process for the production of biofuel and lignin from wood chips.", "[0063] FIG. 5 is the 2D 13 C- 1 H correlation (HSQC) spectra of lignin side chain regions, acquired during NMR analysis of an isolated lignin sample described herein.", "[0064] FIG. 6 is the 2D 13 C- 1 H correlation (HSQC) spectra of side chain region, acquired during NMR analysis of a Kraft lignin (Sigma-Aldrich #370959) sample.", "[0065] FIG. 7 shows the volume integration of the 2D 13 C- 1 H correlation (HSQC) spectra of side aromatic units, acquired during NMR analysis of an isolated lignin sample described herein.", "[0066] FIG. 8 illustrates gel filtration elution profiles showing the molecular weight distribution of an isolated lignin sample of the present invention in FIG. 8A (BJL5), a commercial Kraft lignin (Sigma-Aldrich #370959) sample in FIG. 8B , and a commercial ORGANOSOLV lignin (Sigma-Aldrich, #37101-7) sample in FIG. 8C .", "DETAILED DESCRIPTION [0067] As discussed above, the present invention provides high grade isolated lignin polymers obtained from processing of plant materials, such as lignocellulosic plant materials.", "Ligocellulosic plant materials are harvested, air-dried and stockpiled.", "Reduction of the particle size of the harvested plant material may be desired prior to processing, and this can be achieved using a chipper or similar device to mechanically reduce the size of the plant material feedstock.", "Suitable size reduction techniques are well known in the art and one of ordinary skill in the art may readily determine appropriate particle sizes and size distributions for various types of feedstocks used in the present invention.", "[0068] In one solvent extraction methodology, the first stage of the process disclosed herein is a modified ORGANOSOLV™, or aqueous ethanol extraction (illustrated schematically in FIG. 1 ).", "In one embodiment, this involves continuously contacting a lignocellulosic plant material with a counter-current flow of an aqueous solution comprising up to 80% ethanol, undertaken at a temperature of approximately 170° C. to 210° C. and a pressure of 19-30 barg.", "In one embodiment, the digester is a screw contactor operating with wood chips being fed and discharged via cup and cone pressure plugs or feed screws.", "Solvent passes against the flow of solids so that plant material exiting the digester is exposed to fresh (solute free) ethanol solution, while chips entering the digester, which have the highest extractable content, are exposed to the most solute laden solvent solution.", "[0069] Solvent entering the digester may be pressure pumped to maintain the operating pressure therein and to provide the hydraulic drive to pass against the flow of chips.", "Solvent from within the digester is re-circulated through external heaters, for example steam heaters, on a continuous basis to bring the wood chips up to the operating temperature quickly and to maintain the temperature.", "Operating conditions (such as time, temperature profile, pressure and solids/liquid ratio) within the digester may be optimized to provide maximum removal of water insoluble lignin from the plant material.", "As the plant material exits the digester and is exposed to lower pressures, a portion of the solvent content therein evaporates, resulting in cooling of the treated plant material.", "In alternative embodiments, the plant material may be displaced in the digester using gravity in a downward gradient.", "Solvent entering the digester may be pumped against the flow of solids.", "Multiple solvent extraction stages may be provided.", "Lignin is solubilized in the aqueous ethanol solvent (“black liquor”) and may be isolated from the “black liquor”", "produced during solvent extraction.", "[0070] Plant material, or pulp, discharged from a solvent extraction stage of the process still contains some ethanol, which is preferably removed prior to a subsequent water extraction step.", "Solvent removal may be achieved by means of a steam stripping operation.", "The vapors recovered from both this operation and from other solvent recovery techniques, may be collected and re-used directly with the fresh solvent stream.", "In this way the latent heat content of the vapors is recovered.", "[0071] The de-solventized plant pulp material may optionally be processed in a second stage of extraction (illustrated schematically in FIG. 2 ), which may be undertaken in comparable equipment and in a comparable fashion to the ethanol extraction described above, with the difference being that high pressure hot water (preferably at a pressure of approximately 2 to 25 barg and a temperature of approximately 130° C. to 220° C.) is utilized to solubilize the hemicellulose sugars in the plant pulp material.", "As the solids exit the hot water digester and the pressure is reduced, flash evaporation of steam occurs.", "This may be recovered for direct re-use with the fresh hot water entering as fresh extraction solvent at the solids discharge end of the digester.", "The treated plant pulp is also cooled as a result of this flash evaporation.", "[0072] The non soluble constituents of the initial plant material that remain in the pulp after two stages of extraction (solvent and hot water) are primarily cellulose and other sugars present in the form of a hydrolyzable pulp.", "This material may be hydrolyzed to produce glucose.", "In one hydrolysis procedure, the hydrolyzable pulp is transferred to one of a series of batch SSF (simultaneous saccharification and fermentation) vessels, together with temperature-tolerant yeast, yeast growth media, cellulase, β-glucosidase, buffer and water to dilute the solids to the required solid/liquid ratio (illustrated schematically in FIG. 3 ).", "In these vessels, the cellulose is hydrolyzed to produce glucose, which is in turn fermented to produce ethanol.", "Low levels of ethanol are maintained in the fermentor by continuous removal of the produced ethanol to avoid fermentation inhibition.", "The process is optimized for maximum cellulose hydrolysis and fermentation to ethanol.", "The vessel contents at the end of the batch fermentation will be discharged via a filter and the retained solids will be disposed of, or recovered to be further processed to yield additional products.", "The filtrate, consisting primarily of ethanol and water, may be concentrated to produce hydrous and/or anhydrous ethanol as desired, using methods well known to those of skill in the art.", "A portion of the hydrous ethanol product may be re-utilized in the first, ethanol extraction stage.", "[0073] Products, such as high grade lignin, are separated and purified as illustrated schematically in FIG. 4 .", "In one embodiment, the black liquor (ethanol/water/lignin solution) exiting the solvent extraction digester in the first stage may be depressurized before passing to a flash cooling vessel in which the solvent is evaporated.", "Further ethanol may then be steam-stripped from the liquor prior to transfer to one of a series of batch vessels, in which precipitation of lignin from the liquor is promoted through dilution (generally from about 2 to 10 times, by volume) with water.", "The pH of the diluted black liquor may be reduced by acid addition to increase the lignin precipitation rate, if desired.", "After settling, the lignin sludge may be dewatered by filtration and/or centrifugation and dried to produce an isolated lignin product.", "[0074] Alternatively, the lignin solubilized in the black liquor may be recovered using a dissolved gas flotation (DAF-like) based process as described below.", "Because of its low cost, gentle recovery conditions and rapid recovery, the dissolved gas flotation method described herein is preferred for many lignin isolation and harvesting processes compared to conventional methods like settling and centrifuging and may be used to harvest lignin extracted from plant materials using a variety of extraction techniques.", "In this embodiment, after flash cooling, the black liquor may optionally be filtered and the solubilized lignin in an aqueous solvent solution is then mixed with a gasified aqueous solution (e.g., water).", "The gasified solution contains a high concentration of a gas such as air, nitrogen, CO 2 , mixtures thereof, and the like.", "The pressure and gas flow rates may be adjusted to provide desirable gas concentrations, properties, etc.", "in the lignin recovery vessel.", "[0075] Gasified aqueous solutions may be prepared, for example, by storing water in a pressure vessel under nitrogen, carbon dioxide or any other suitable gas at a pressure of at least 2 barg.", "The water level in the pressure vessel is regulated by the use of a float valve or similar device.", "Compressed air, nitrogen or carbon dioxide (such as CO 2 recovered from the fermentation process) may be admitted at the base of the tank, and the incoming gas may be passed through a sparger to increase the dissolution rate of the gas in the aqueous solution.", "The gasified solution is withdrawn from the pressure vessel through a metering valve which regulates its flow rate.", "As the gasified solution leaves the tank and is mixed with the black liquor, the decrease in pressure leads to the generation of many small gas bubbles (“microbubbles”) which attach to the hydrophobic lignin precipitate as it forms, and cause it to float to the surface.", "[0076] In one embodiment, (optionally filtered) black liquor comprising lignin solubilized in an aqueous solvent solution is pumped (using, for example, a metering pump) into a mixing device, such as a venturi mixer or a similar device.", "The mixing device preferably creates conditions of high fluid shear to provide rapid and complete mixing of the gasified water with the black liquor, and is preferably constructed from materials that minimize the amount of lignin adhering to the surfaces of the device.", "When the solubilized lignin is diluted in the aqueous solution, the hydrophobic lignin precipitates and forms immiscible particulates in the aqueous solution.", "Microbubbles of gas attach themselves to the immiscible lignin particles and transport them to the surface of the mixed solution.", "The floating lignin may then be separated by mechanical means.", "In one embodiment, the floating lignin particulates are pushed toward a conveyer belt by means of a paddle, for example.", "The conveyer belt may be constructed from a porous material, allowing partial dewatering of the lignin as it is harvested.", "The speed and length of the conveyer belt may be adjusted to provide optimum harvesting efficiency and lignin drying.", "It will be apparent to one of ordinary skill in the art that different types of lignin harvesting processes may also be used.", "After lignin removal, the ethanol may be separated from the water and recycled, while the aqueous fraction may be combined with a hot water stream for use in further processing, such as xylose and water soluble product recovery.", "[0077] The present invention further provides methods for recovering lignin from an aqueous suspension of lignin.", "In one embodiment, the lignin may be recovered from water washes by a process in which ammonium salts (e.g., 10 mM ammonium chloride or ammonium sulfate, but not ammonium bicarbonate) or low concentration detergents (e.g., 50 parts per million of Triton™ X-100 ((C 14 H 22 O(C 2 H 4 O)n) or Nonidet™ P40 (nonylphenyl-polyethylene glycol), but not Tween™ 80 (polyoxyethylene (20) sorbitan monooleate) or sodium dodecyl sulphate, are added to the solution.", "This causes the lignin suspended in the water washes to flocculate, facilitating harvesting of the washed lignin.", "The effects of detergents and ammonium salts are additive.", "The use of ammonium chloride to aid in the harvesting of washed lignin precipitates may be particularly advantageous, as ammonium chloride is volatile, and excess ammonium chloride can thus be easily removed from the harvested lignin during the drying process.", "Ethanol may also be used to recover the washed lignin.", "At low concentrations (for example less than 35% v/v), ethanol induces the precipitation of lignin from a water suspension.", "The use of ethanol in this process is particularly advantageous because it is volatile and can thus be easily removed from the harvested lignin during the drying process.", "[0078] Raw lignin material isolated from Salix viminalis or Salix schwerinii ‘Kinuyanagi’ using the process described above employing 70% aqueous ethanol at 185° C. for 60 minutes, and harvested by precipitation and centrifugation from the black liquor or using the dissolved gas flotation described above, was shown to have a high degree of similarity to natural lignin, to retain a high degree of reactivity and to be relatively pure, with a minimal amount of carbohydrate contamination.", "In preferred embodiments, isolated lignin preparations of the present invention comprise less than about 1.0% sugars;", "in some embodiments less than about 0.2% sugars and, in yet additional embodiments, less than about 0.5% sugars.", "In some embodiments, isolated lignin compositions of the present invention have a carbohydrate composition of less than about 0.2 g per liter supernatant detectable by HPLC using an ion exclusion column following hydrolysis of the lignin preparation with concentrated sulfuric acid.", "In addition, isolated lignin preparations of the present invention are substantially free from salts and particulate components.", "[0079] Isolated lignin having a relatively high ratio of syringyl (S) units is preferred for many applications.", "Lignin extracted from Salix viminalis or Salix schwerinii ‘Kinuyanagi,’ or a mixture of both species, with 70% ethanol at 185° C. for a retention time of 60 minutes and harvested by precipitation and centrifugation was composed of approximately 80% syringyl (S) units (ratio S:G of 4:1) and had a low degree of chemical modification with a high proportion of β-aryl-ether and resinol subunits.", "In some embodiments, isolated lignin compositions of the present invention have a syringyl unit content of at least about 50%, in some embodiments, of at least about 60%, in yet other embodiments, of at least about 70%, and in still other embodiments of at least about 80%.", "Isolated lignin compositions of the present invention preferably have an S:G ratio of at least about 2:1;", "more preferably at least about 3:1 and, even more preferably for some applications, at least about 4:1.", "[0080] Isolated lignin preparations made as described herein have an average molecular weight of about two to three times higher than comparative commercial Kraft and ORGANOSOLV lignin preparations, as demonstrated by the experimental evidence presented in Example 6, below.", "In some embodiments, isolated lignin compositions of the present invention have a weight average molecular mass (determined as described below) of at least about 4,000.", "In some embodiments, isolated lignin compositions disclosed herein have a weight average molecular mass (determined as described below) of at least about 4,500, and in yet other embodiments, the disclosed isolated lignin compositions have a weight average molecular mass (determined as described below) of at least about 5,000.", "In still other embodiments, isolated lignin compositions of the present invention have a weight average molecular mass (determined as described below) of at least about 5,500.", "[0081] The isolated lignin preparations also have relatively high numbers of reactive hydroxyl groups that are important to provide reactivity with other chemicals or polymers, as well as high numbers of methoxyl groups of 30 to 40 per 100 units.", "In addition, the high grade isolated lignin disclosed herein is minimally modified and therefore has a reactivity that is closer to that of natural (“native”) lignin.", "Isolated lignin compositions of the present invention generally comprise detectable quantities of at least three side chains selected from the group consisting of phenylcoumaran, resinol, α-ethoxy-β-aryl-ether, and cinnamyl alcohol side chains.", "According to some embodiments, isolated lignin compositions of the present invention comprise detectable quantities of phenylcoumaran, resinol, α-ethoxy-β-aryl-ether, and cinnamyl alcohol side chains.", "The side chains present in isolated lignin preparations may be detected and measured using nuclear magnetic resonance spectroscopy analysis, for example.", "[0082] High grade isolated lignin compositions of the present invention generally have a high ratio of β-aryl-ether subunits, generally at least about 40%, in some embodiments at least about 50%, and in yet other embodiments at least about 60%.", "High grade isolated lignin compositions of the present invention also have a generally high ratio of resinol subunits, generally at least about 6%, in some embodiments at least about 8%, and in yet other embodiments at least about 10%.", "[0083] Because of its purity, homogeneity and unique reactivity, the isolated lignin preparations obtained as described herein can be used without further processing.", "However, if desired, residual volatile compounds may be removed by heat treatment, and non-volatile residual compounds may be removed, for example, using a water wash.", "In some embodiments, the isolated, raw lignin may be recovered from a water suspension using a selective flocculation method as described herein.", "In some embodiments, the isolated lignin may be harvested from the black liquor using a dissolved gas flotation technique as described herein.", "[0084] The high grade isolated lignin disclosed herein is useful as a feedstock for a variety of downstream industrial processes and material manufacturing processes.", "In one embodiment, the high grade isolated lignin described herein can be melted or dry spun at a desired temperature and speed to produce carbon fibers using methods well known to those of skill in the art and including, but not limited to, those taught in U.S. Pat. Nos. 3,461,082 and 5,344,921.", "Because of its homogeneity, the disclosed lignin has the capacity to form regular, continuous filaments of carbon during extrusion.", "Also, because of the higher S unit ratio and lower condensation level, lignin prepared from Salix using the process described herein is stable during the thermostabilization of the carbon filament.", "If required, the spinning, extrusion and/or carbonization can be facilitated by blending the disclosed lignin with a plasticizer (for example polyvinyl alcohol (PVAL), polyethylene oxide (PEO) or polyester (PES)) or by condensation of lignin units following chemical modification of the lignin.", "The melting and extrusion of polycondensed high grade lignin or lignin polymer blend can also be useful for the production of composites and plastics.", "[0085] Superior lignin-based polyurethane (PU) can be formulated by using the disclosed lignin either directly as a polyol precursor or blended with other polyol types (for example, polyethylene glycol (PEG), polyethyleneadipate (PEA) and/or polypropylene glycol (PPG)) to react with an isocyanate radical of polyisocyanates or isocyanate-terminated polyurethane prepolymers either in the presence or absence of a catalyst.", "The efficient functionalization of the disclosed lignin with diisocyanates also allows, upon reaction with polyols, the formulation of a high quality PU resin.", "In addition, the disclosed lignin can be functionalized with an epoxide for further reaction with an isocyanate or added as filler to a prepared PU resin.", "PU resin prepared using the disclosed high grade lignin can be used as a lower cost, high quality, adhesive and/or coating, or can be easily cast and cured for the formation of high quality films.", "When water or a foaming agent is added to the formulation of the lignin based PU, foams of various density levels can be produced.", "[0086] Superior phenolic resins can also be formulated from the disclosed high grade lignin.", "Because of its higher reactivity compared to Kraft and sulfite lignins, the disclosed lignin will provide a superior replacement of phenol in many phenol based resins used in a wide variety of applications, ranging from adhesives to composites.", "The disclosed high grade lignin can be either directly blended with the phenol resin or incorporated into the resin at high ratios by condensation or derivatization with phenol or formaldehyde.", "The disclosed lignin may thus be used to produce a safe and biodegradable resin.", "[0087] The natural properties of the high grade lignin disclosed herein can be modified by polymer blending.", "The lignin is able to form proper hydrogen bonding for miscible blend formation with plasticizing agents such as polyethylene oxide (PEO), polyethylene terephthalate (PET), polyvinyl pyrrolidone (PVP), polyvinyl chloride (PVC), polyvinyl acetate (PVA), polyethene-co-vinylacetate (EVA), polypropylene (PP), polyethylene (PE) and others, allowing further control of its thermal processability.", "This can be useful, for example, to facilitate the spinning, extrusion and/or casting of the lignin-based final product, or in the making of adhesives, paints coatings, plastics and the like.", "The stronger intermolecular interaction between polymers and the disclosed high grade lignin will create superior lignin-polymer blends with a positive impact on the derived composite.", "[0088] The viscoelastic properties of lignin can also be altered and modified through chemical introduction of unsaturated carbonyl groups or nitrogen-containing compounds.", "Another advantage of the unique properties of the disclosed high grade lignin is the efficiency and lower cost of chemical conversion of its phenol, alkene or hydroxyl moieties into other functional groups.", "The disclosed lignin is more amenable to alkylation and dealkylation, oxyalkylation (for example, oxypropylation, for production of polyoxyalkylene polyethers), amination, carboxylation, acylation, halogenation, nitration, hydrogenolysis, methylolation, oxidation, reduction, polymerization, sulfomethylation, sulfonation, silylation, phosphorylation, nitroxide formation, grafting and composite formation.", "In general, such lignin modifications are inefficient and costly due to the presence of impurities, heterogeneity and high level of altered moieties in the conventional lignin preparations.", "These modifications can be performed more efficiently and at lower cost on the disclosed high grade lignin to produce useful polymeric materials.", "[0089] Reactive epoxy functionality can be added at lower cost to the disclosed high grade lignin than with conventional lignin preparations.", "The disclosed lignin can be directly reacted with ethylene-unsaturated groups or hydroxypropyl groups to prepare a lignin-based epoxide with good solubility that may be used in co-polymerization reactions.", "The disclosed lignin is also a superior substrate for conversion into polyols by propoxylation (reaction with propylene oxide such as 2-methyloxirane) or ethoxylation (reaction with ethylenoxide such as oxirane) chain extension reaction.", "Epoxide-lignin resin may be cured to a hard infusible plastic and may also be reacted with fatty acids to produce resins for paints and inks or may be reacted with various amines to produce polyamines or polyamides for use as adhesives or plastics.", "Epoxidized high grade lignin may also be employed to reduce the need for polyol in PU resin and for displacement of phenol epoxy resin.", "[0090] The following examples are offered by way of illustration and not by way of limitation.", "Example 1 Recovery of Lignin from Salix Preparation and Composition Analysis of Untreated Salix Biomass [0091] Stems of Salix viminalis or Salix schwerinii ‘Kinuyanagi’ were chipped with a garden mulcher.", "The wood chips were dried at 40° C. for 24 hours and sieved by hand between two wire meshes of British test sieve with apertures of 2.8 and 4 mm.", "The composition of the sieved and unsieved Salix chips was assessed, with the results being shown in Table 1.", "The mass composition was assessed using laboratory analytical procedures (LAPs) developed by the National Renewable Energy Laboratory (NREL, Golden, Colo.).", "Values are expressed as gram of component per 100 g of dry untreated chips.", "Extractives were isolated using a Soxhlet extractor, dried and weighed.", "Lignin concentrations were determined after chemical hydrolysis of the Salix chips (4 hours with 72% sulfuric acid at 102° C.).", "Acid soluble lignin was measured by densitometry at 320 nm and the concentration of the non-acid soluble lignin was measured by weight minus ash.", "The percentage of glucan and xylan present in the samples were determined after chemical hydrolysis (4 hours with 72% sulfuric acid at 102° C.).", "Acid soluble sugar was measured by HPLC using the appropriate range of xylose and glucose standards.", "The composition of the untreated Salix material was determined and is shown below in Table 1.", "[0000] TABLE 1 Composition of untreated Salix biomass (*= Sieved material) Ex- trac- tive Lignin (%) Sugar (%) Salix variety (%) Soluble Insoluble Total Glucan Xylan Salix viminalis * 16 2 31 33 23 9 Salix viminalis 8 3 24 27 34 8 Salix schwerinii 6 5 23 28 32 14 Salix schwerinii 4 5 22 27 33 12 Kinuyanagi Salix schwerinii 4 3 25 28 33 9 Kinuyanagi Salix schwerinii 2 4 28 32 35 9 Kinuyanagi + Salix viminalis Salix schwerinii 2 4 25 29 30 8 Kinuyanagi + Salix viminalis Average 6 4 25 29 31 10 Standard 5 1 3 3 4 2 Deviation Pre-Treatment of Salix Biomass [0092] A modified ORGANOSOLV™ treatment of Salix chips was tested in 100 ml experimental digester and 3 l packed-bed experimental digester that were able to process 6 g and 300 g of dry wood chips, respectively.", "The design of these two digesters is illustrated in and described with reference to FIG. 5 (100 ml digester) and FIG. 6 (3 l packed-bed digester) of U.S. Patent Publication US 2007/0259412 A1.", "A 40 l digester was also designed and tested for the recovery of natural lignin from Salix biomass at larger scale (shown in and described with reference to FIG. 7 of U.S. Patent Publication US 2007/0259412 A1).", "The 40 l digester processed 6 kg of dry biomass.", "Process conditions for solvent treatment of the Salix chips and subsequent hot water treatment of the plant pulp material recovered from the solvent treatment are also described in U.S. Patent Publication US 2007/0259412 A1.", "Lignin from the 100 ml and 3 l digesters was harvested by precipitation and centrifugation as described in U.S. Patent Publication US 2007/0259412 A1.", "Lignin from the 40 liter digester was harvested by precipitation and centrifugation and, in some instances, by dissolved air flotation techniques described herein.", "[0093] At all scales (100 ml, 3 l packed-bed, and 40 l batch), sequential solvent extraction using an aqueous solution comprising 70% ethanol followed by hot water treatment resulted in the removal of over 30% of the total lignin content of the untreated chips.", "The majority of the lignin (28 to 32%) was solubilized during the solvent extraction using the 70% ethanol aqueous solution, and an additional 3 to 8% of the total lignin was removed during the subsequent hot water treatment.", "[0094] The ratio of lignin to DM removed by the 70% ethanol treatment reached 35% in the first hour of treatment retention time at a temperature of 170° C. to 190° C. using the 100 ml and the 3 l packed-bed digesters.", "The lignin composition of the DM removed in the 3 l packed-bed digester during the second hour of treatment retention time increased by 5% and reached 50% after 4 hours.", "After 8 hours retention time in the reactor, the lignin content of the DM removed increased only by another 10% to reach 60%.", "In the 40 l batch digester, the ratio of lignin to DM removed varied from 30 to 48% when Salix dry chips were treated with 70% ethanol solvent.", "The proportion of the total lignin content in the untreated chips that was recovered in the 70% ethanol solvent using each of the three digesters varied over time.", "The high recovery of total lignin (32%±3) in 60 minutes using the smaller 100 ml digester reflected the higher rate of DM removal achieved with this digester.", "With the 3 l packed-bed digester, similar recovery was achieved within 200 to 240 minutes of treatment retention time.", "The amount of total lignin recovered using the 40 l batch digester varied between 22 and 44% of the initial lignin content of the Salix chips, corresponding to 6 to 13% of the initial DM loaded.", "Example 2 Harvesting Precipitated Lignin by Dissolved Air Flotation [0095] Lignin was precipitated from black liquor, and the precipitate harvested using a dissolved gas (air) flotation technique (“DAF”), as follows.", "Water was supersaturated with nitrogen by storage under elevated nitrogen pressure (2 barg) for at least 30 minutes.", "The water was allowed to leave the pressure vessel through a metering valve which regulated the flow rate of aerated water at 26 ml/min.", "Filtered black liquor (containing 12.4 g of lignin per liter) was pumped from the black liquor tank at various flow rates using a peristaltic pump.", "The aerated water and black liquor were mixed in a venturi mixing device and delivered into a flotation tank.", "Upon rapid mixing with the gassified water, the lignin in the black liquor precipitated, flocculated and floated to the surface of the tank.", "The supernatant passed under a dam and overflowed out of the tank.", "Based on the tank volume and the liquid flow rates, the residence time of the precipitate in the tank was calculated to be about three minutes.", "A paddle wheel device was used to move the lignin precipitate to one end of the precipitation tank.", "A porous moving belt of nylon mesh was used to lift the precipitated lignin out of the tank and drain off the supernatant liquid.", "A Perspex scraper was used to harvest the lignin from the belt and allow it to fall into the collection tank.", "[0096] The relative flow rates of the aerated water and black liquor were varied, and the best yields of precipitated lignin were obtained where the water flow rate was at least three times the black liquor flow rate.", "Various venturi mixing devices were tested, and the best devices were found to be those which delivered the black liquor into the venturi through a small nozzle having a diameter of approximately 0.2 mm.", "This provided black liquor linear velocities of about 5 msec, implying that high shear rates are important to give good mixing.", "The venturi throat which gave best mixing had a diameter of 1 mm, which would give a linear flow rate for the mixture of 0.7 msec.", "[0097] Use of the optimal conditions detailed above gave a lignin harvesting yield of 89% of theoretical.", "A further 3.6% of the lignin yield remained in suspension, and floated to the surface of the supernatant at later times.", "This suggests that a longer residence time of the precipitate in the tank would give a higher yield.", "The lignin sludge harvested from the belt was found to contain 4% w/v lignin.", "Pressing the sludge between two pieces of filter paper increased the lignin concentration to 20% w/v.", "This indicates that a belt press or similar device could be used to increase the solids content of the lignin sludge, and consequently facilitate drying of the sludge.", "After air-drying, the lignin harvested by the DAF technique disclosed herein yielded a light brown powder containing about 10% moisture.", "[0098] The precipitation was found to occur optimally at a temperature of about 20° C. Temperatures above 35° C. gave a dense, sticky precipitate in poor yield.", "Example 3 Large-Scale Harvesting of Lignin by DAF [0099] Lignin was precipitated from black liquor, and the precipitate harvested by dissolved gas (air) flotation, on a larger scale as follows.", "Water was supersaturated with air by storage under compressed air pressure (2 barg).", "The water was allowed to leave the pressure vessel through a metering valve which regulated the flow rate of aerated water at 4.5 l/min.", "Filtered black liquor (containing 14.8 g of lignin per liter) was pumped from the black liquor tank at 1.4 l/min using a peristaltic pump, and the aerated water and black liquor were mixed in a venturi mixing device and delivered into a flotation tank.", "(The mixing ratio of aerated water to black liquor was 3.2:1) The venturi jet had a diameter of 2.5 mm, which would yield a black liquor linear velocity of 1.2 msec.", "The venturi throat had a diameter of 7 mm, implying a linear velocity for the mixture of 2.6 msec.", "The lignin in the black liquor precipitated, flocculated and floated to the surface of the tank.", "When the tank was full the floating lignin was allowed to stand for 30 mins and then harvested manually with a plastic scoop.", "The solids content of the lignin sludge varied in repeated experiments from 6-14% lignin w/v.", "The sludge was placed in a porous fabric bag and allowed to drain overnight.", "This typically increased the lignin solids content to about 23% w/v.", "The lignin sludge was then air-dried and sieved to yield a light brown powder containing about 10% moisture.", "Example 4 Flocculation of an Aqueous Lignin Suspension [0100] The ability of various additives to cause flocculation of lignin in an aqueous suspension of lignin was examined.", "The results of these studies are provided in Table 2, below.", "[0000] TABLE 2 Flocculation of lignin Additive Concentration suspension Ammonium 2 mM − chloride 4 mM − 20 mM ++ 40 mM ++ 80 mM ++ 200 mM ++ 400 mM ++ Nonidet ™ 0.4 ppm − P40 1 ppm − 4 ppm − 12 ppm + 37 ppm ++ 111 ppm ++ 333 ppm ++ 1,000 ppm ++ Ethanol 1% v/v − 2% v/v + 4% v/v + 9% v/v ++ 12% v/v ++ 17% v/v ++ 29% v/v ++ 38% v/v + 44% v/v * 50% v/v * ++: Flocculation +: Partial flocculation −: No flocculation * Clear solution (precipitate dissolved) [0101] Ammonium chloride at concentrations between 20 mM and 400 mM caused the lignin suspension to flocculate.", "Concentrations of greater than 400 mM were not tested.", "Ammonium sulfate and ammonium bicarbonate were also tested for their ability to cause flocculation of the lignin suspension.", "Ammonium sulfate gave similar results to ammonium chloride while ammonium bicarbonate had a weak effect at 400 mM and no effect at lower concentrations.", "Nonidet™ P40 at concentrations between 37 ppm and 1,000 ppm caused the lignin suspension to flocculate, with a weak effect being seen at 12 ppm and no effect at lower concentrations.", "Concentrations of greater than 1,000 ppm were not tested.", "Triton™ X-100 and Triton™ X-114 gave similar results to Nonidet™ P40.", "Sodium deoxycholate showed a weak effect at 1,000 ppm and no effect at lower concentrations.", "No effect was shown with sodium dodecyl sulfate, Tween™ 20, Tween™ 80, α-methyl mannoside, Brij™ 76, Brij™ 700, Lubrol™ PX or cetyltrimethylammonium bromide (CTAB).", "[0102] Ethanol at concentrations between 29 and 9% v/v caused the lignin suspension to flocculate.", "At ethanol concentrations of 4% and 2% there was a weak effect, with no effect being seen at a concentration of 1% v/v.", "Ethanol at 38% v/v and higher caused the lignin precipitate to dissolve.", "Example 5 Properties of Lignin Isolated from Salix as Determined by NMR [0103] The lignin preparation submitted for NMR analysis was isolated by the treatment of 6.54 g (dry weight) of Salix schwerinii ‘Kinuyanagi’ dry chips with an aqueous solvent comprising 70% ethanol at 190° C. for 100 minutes in the 100 ml digester.", "The lignin recovered from the black liquor by precipitation and centrifugation was dissolved in DMSO-d6 for nuclear magnetic resonance spectroscopy analysis (as described in Ralph et al.", ", 2006, Journal of Biological chemistry 281(13):8843) and compared to a commercially available Kraft lignin preparation (Sigma-Aldrich #370959).", "The 2D spectra of the lignin side chains from the NMR analysis for the Salix lignin isolated using the methodology described herein is shown in FIG. 5 , and the 2D spectra of the lignin side chains from the NMR analysis for a commercial Kraft lignin preparation is shown in FIG. 6 .", "[0104] FIG. 5 illustrates the distribution of lignin side chains, including β-aryl ether (identified as “A”), phenylcoumaran (identified as “B”), resinol (identified as “C”), α-ethoxy-β-aryl ether (identified as A2) and cinnamyl alcohol side chains (identified as X1) retained in the lignin isolated using the modified ORGANOSOLV™ process described herein.", "FIG. 6 illustrates that minute quantities of β-aryl ether (identified as “A”) were present in the isolated Kraft lignin preparation, while there were no detectable quantities of phenylcoumaran, resinol, α-ethoxy-β-aryl ether or cinnamyl alcohol side chains.", "The lignin subunit distribution was quantified via volume-integration of the 2D contours in HSQC spectra, with minor corrections.", "The high ratio of β-aryl-ether (73%) and resinol (12%) subunits in the high grade isolated lignin preparation described herein is indicative of a higher degree of conservation of native structure.", "The destruction of the lignin side chains that occurs during Kraft pulping is shown by the absence of signal in the NMR spectra ( FIG. 6 ) indicating the presence of the native lignin side chains in the commercial Kraft lignin sample.", "These results demonstrate that lignin isolated using the methodology described herein retains a more “natural”", "structure than commercially available Kraft lignin, with the retention of a large proportion of the side chain structures that are important for lignin reactivity.", "[0105] The lignin isolated according to methods described herein also demonstrated a higher methoxyl content than the commercially available Kraft lignin (30 to 40% as determined by volume-integration of the 2D contours in HSQC spectra, FIG. 5 ), making it desirably less likely to re-condense and more amenable toward chemical reaction.", "[0106] The spectra shown in FIGS. 5 and 6 identify unresolved or unknown (non-lignin) components, such as saccharides, as “U.”", "These unresolved and unassigned constituents are contaminants in a lignin preparation.", "It is evident from the spectra illustrated in FIGS. 5 and 6 that the commercially available Kraft lignin preparation is highly impure and has a high level of contamination, while the lignin preparation of the present invention has considerably fewer contaminants.", "In fact, nearly all of the material detected in the commercially available Kraft lignin preparation is contaminant material.", "While contaminants are present in the lignin preparation of the present invention ( FIG. 5 ), those contaminants represent a far less significant proportion of the preparation.", "[0107] Additionally, no sugars were detectable when the disclosed isolated lignin preparation was hydrolysed with concentrated sulfuric acid and the supernatant analysed by HPLC (High pressure liquid chromatography) on an ion exclusion column (BioRad Phenomenex Rezex™) with a lower detection limit of 0.2 g of sugars (glucose or xylose) per litre.", "[0108] Lignin isolated from Salix schwerinii ‘Kinuyanagi’ using the above process was composed of about 80% syringyl (S) units and a ratio of syringyl:guaiacyl units of about 4:1 as quantified by volume integration of the 2D contours in HSQC spectra ( FIG. 7 ).", "This high ratio of S lignin is also reflected by the relatively high content of O-methoxyl groups (40%, FIG. 5 ).", "Example 6 Additional Properties of Lignin Isolated from Salix [0109] The molecular weight average and molecular weight distribution of several samples of the disclosed high grade isolated lignin were calculated from the gel filtration elution profile of the lignin preparation ( FIG. 8 ) on a Superdex Peptide column (GE Healthcare #17-5176-01 10/300 GL, as described by Reid (1991), Biotechnol.", "Tech, 5:215-218).", "Lysozyme, aprotinin and 3,4-dimethylbenzyl alcohol were used as standards for calibration and therefore these molecular weights should be taken as relative values.", "Isolated lignin samples were prepared as described above using lignin harvested by precipitation and centrifugation (Samples BJL2-5) and lignin harvested using the DAF process described herein (Sample BJLD) were dissolved at 0.5 mg/ml in 50% ethanol/50 mM NaOH for the gel filtration analysis.", "Commercially available lignin samples were prepared for comparative analysis, including a Kraft lignin preparation (Sigma-Aldrich #370959) and an ORGANOSOLV lignin preparation (Sigma-Aldrich, cat.", "No. 37, 101-7).", "Each sample was analysed in duplicate with an injection volume of 200 μl.", "The results are shown in FIG. 8 and summarized in Table 3, below.", "[0110] The majority of the lignin (at the elution peak) in the isolated lignin samples prepared as disclosed herein and harvested by precipitation and centrifugation (samples BJL2-5), had an average molecular mass of approximately 6,500 g/mol.", "This molecular mass is about 2 to 3 times greater than the molecular mass of the majority of the lignin (at the elution peak) in the commercially available Kraft lignin composition (Sigma-Aldrich #370959;", "molecular mass 1,942 g/mol) or the commercially available ORGANOSOLV lignin composition (Sigma-Aldrich, cat.", "No. 37, 101-7;", "molecular mass 2,627 g/mol).", "The weight average molecular mass of the isolated lignin samples BJL2-5 was in excess of 5,200, while the weight average molecular mass of the commercial Kraft lignin preparation was approximately 2,229 and the weight average molecular mass of the commercial ORGANOSOLV lignin preparation was approximately 3,000.", "These values are in agreement with previously published studies using gel filtration for molecular weight analysis of Kraft and ORGANOSOLV lignin preparations from hardwood (Kubo and Kadla (2004) Macromolecules, 37:6904-6911;", "Cetin and Ozmen (2002) Proceedings of ICNP ;", "Glasser et al.", "(1992) J. Wood Chem.", "and Technol.", "13:4, 545-559), with slightly higher polydispersity (PD) values.", "The isolated lignin sample prepared as disclosed herein and harvested using the DAF process described here (Sample BJLD) had an average molecular mass of over 7,200 and a weight average molecular mass of over 5,500.", "[0000] TABLE 3 Molecular Mass g/mol at elution peak Weight Poly- (n = 2) Average dispersity Lignin Sample Avr StDv (Mw) (PD) BJL2 5,933 0.668 4,871 4.1 BJL3 6,374 0.844 5,384 3.0 BJL4 6,800 0.810 5,372 3.9 BJL5 7,172 0.285 5,450 3.9 BJL Average 6,570 0.535 5,269 3.7 BJLD 7,271 0.049 5,712 3.7 Kraft 1,942 0.218 2,229 3.5 ORGANOSOLV 2,627 0.070 2,992 3.3 Example 7 Reactivity of High Grade Lignin Isolated from Salix [0111] The reactivity of the disclosed lignin was assessed by measurement of the total and phenolic hydroxyl groups and compared with the commercial Kraft and ORGANOSOLV lignin preparations (Table 4, below).", "The total amount of hydroxyl functional group in each lignin sample is expressed as a potassium hydroxide equivalent and was measured using standard testing method (ASTM D4274-05).", "The amount of phenolic hydroxyl groups in each lignin sample was assessed by differential spectrophotometry as described by Wexler (Analytical Chemistry 36(1) 213-221 (1964)) using 4-hydroxy-3-methoxybenzyl alcohol as a calibration standard.", "In this analysis, the amount of phenolic hydroxyl is relatively low for all the lignin samples analysis and the total amount of hydroxyl measurements do not vary greatly among the samples (Table 4).", "However, the ratio of phenolic to total hydroxyl is lower in the disclosed lignin samples (BJL2, BJL-5 and BJLD) as compared with the Kraft and ORGANOSOLV commercial lignin preparations.", "[0000] TABLE 4 Hydroxyl Numbers mmol/g Ratio Lignin Sample Total Phenolic Phenolic:Total BJL2 6.06 0.33 0.054 BJL5 6.23 0.28 0.044 BJLD 5.40 0.29 0.054 ORGANOSOLV 5.78 0.38 0.066 Kraft 6.41 0.40 0.062 Example 8 Production of Urethane Foam Using Isolated Lignin of the Present Invention [0112] Rigid polyurethane (PU) foam was produced using lignin derived from Salix and isolated as described herein.", "The foam was tested and demonstrated excellent thermal conductivity and density properties.", "The density of the rigid PU foam produced using isolated lignin was 0.62 g/cm 3 compared to a density of rigid PU foam produced using conventional feedstocks of 0.05 g/cm 3 .", "The thermal conductivity of the rigid PU foam produced using isolated lignin was 0.030 to 0.032 compared to a thermal conductivity of rigid PU foam produced using conventional feedstocks of 0.035.", "The thermal degradation temperature of the rigid PU foam produced using isolated lignin was 295° C.;", "the compression strength was 0.5 MPa;", "and the compression modulus was 19 MPa.", "[0113] While the present invention has been described with reference to the specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention.", "In addition, many modifications may be made to adapt a particular situation, material, composition of matter, method, method step or steps, for use in practicing the present invention.", "All such modifications are intended to be within the scope of the claims appended hereto.", "[0114] To the extent that the claims appended hereto express inventions in language different from that used in other portions of the specification, applicants expressly intend for the claims appended hereto to form part of the specification and the written description of the invention, and for the inventions, as expressed in the claims appended hereto, to form a part of this disclosure.", "[0115] All of the publications, patent applications and patents cited in this application are herein incorporated by reference in their entirety to the same extent as if each individual publication, patent application or patent was specifically and individually indicated to be incorporated by reference in its entirety." ]
BACKGROUND OF THE INVENTION In the security and safety-paper printing and marketing industry, particularly for checking account customer supplies for banks and similar institutions, the availability at each bank branch information or new account deck of customer supplies order-taking book or kit of some type has come to be an essential marketing tool, both for the bank and for the supplier. Traditionally, the books or kits have taken the form of a spiral-bound, ring-bound or loose-leaf book, with pages of suggestions, specimens and the like. SUMMARY OF THE INVENTION It is an object of the invention to provide a kit, primarily for use in marketing customer supplies, e.g. checks, check books, and check book covers, which is the form of a three panel per side portfolio, including a pocket for order forms, clear plastic coating on one face of the portfolio blank which folds and is secured to provide six panel faces of protected graphics, and a single layer in the integral hinge regions for compact folding. The principles of the invention will be further discussed with reference to the drawings wherein a preferred embodiment is shown. The specifics illustrated in the drawings are intended to exemplify, rather than limit, aspects of the invention as defined in the claims. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings FIG. 1 is a perspective view of a checking account check and check book order-taking portfolio or similar article, in a partially opened condition; FIG. 2 is a top plan view thereof; FIG. 3 is a bottom plan view thereof; FIG. 4 is a rear elevational view thereof; FIG. 5 is an outer end elevational view of the left panel thereof; FIG. 6 is an outer end elevational view of the right panel thereof; FIG. 7 is a perspective view of said portfolio or similar article in a folded-closed condition, looking obliquely toward the lower right corner of the left panel thereof; and FIG. 8 is a perspective view thereof from a diagonally opposite vantage point, looking obliquely toward the upper left corner of the left panel thereof. FIG. 9 is a smaller scale plan view of the non-glazed side of the blank from which the portfolio is assembled; and FIG. 10 is a perspective view of the blank from the non-glazed side, showing all the folds partly made. DETAILED DESCRIPTION In FIG. 9 the blank 10 is shown having been die cut or similarly severed from a supply of preprinted paper board or similar file folder-weight stock, which is e.g. plastic coated on the printed side, in order to extend the life of the portfolio by reducing the potential that abrasion, or perspiration and the like due to handling will make the portfolio look less attractive or become shopworn and not have a desirable look of newness and freshness. The clear coating 12 applied over the printing 14 on the printed side, may be of exactly the prior art sort conventionally used on restaurant menus. The blank 10 includes six rectangular major panels. In the text, these are referred to assuming the following orientation: that the user has the portfolio before him or her in a partially open condition, i.e. as depicted in FIG. 1, so that the "inside" or "front" is facing the user and the "outside" or "back" (shown in FIG. 4) is directed away from the user. Accordingly, the panels are designated herein: inside left 16, outside left 18, inside central 20, outside central 22, inside right 24 and outside right 26. The upper edge 27 of the outside left panel 18 is integrally hinged on a respective horizontal fold line 28 to the upper edge 29 of the inside left panel 16. The outer edge 30 of the outside left panel 18 is integrally hinged on a respective vertical fold line 32 to the basal edge 33 of a narrow (e.g. inch wide) flap 34. The upper edge 36 of the outside central panel 22 is integrally hinged on a respective horizontal fold line 38 to the upper edge 40 of the inside central panel 20. Between the outside left panel 18 and the outside central panel 22 there is provided a first narrow spine panel 42 integrally hinged on respective vertical fold lines 44 and 46 to the right edge 48 of the outside left panel 18 and the left edge 50 of the outside central panel 22. Between the outside central panel 22 and the outside right panel 26 there is provided a second narrow spine panel 52 which typically is about half as broad as the first spine panel 42, and is integrally hinged on respective vertical fold lines 54 and 56 to the right edge 58 of the outside central panel 22 and the left edge 60 of the outside right panel. The inside left panel 16 is slightly narrower than the outside left panel 18, so that neither of its vertical side edges 62, 64 interferes with folding on the fold lines 32, 44. Likewise, the inside central panel 20 is slightly narrower than the outside central panel 22, so that neither of its vertical side edges 66, 68 interferes with folding on the fold lines 46, 54. The inside left and central panels 16 and 20 respectively are no longer than and at least approximately as long as the respective outside left and outside central panels 18 and 22. The upper edge 70 of the outside right panel 26 is integrally hinged on a respective horizontal fold line 72 to an outer edge 74 of an upper narrow boxing panel 76. The upper edge 78 of the inside right panel 24 is integrally hinged on a respective horizontal fold line 80 to the inner edge 82 of the upper boxing panel 76. The lower edge 84 of the inside right panel 24 is integrally hinged on a respective horizontal fold line 86 to the inner edge 88 of the lower boxing panel 90. The outer edge 92 of the lower boxing panel 90 is integrally hinged on a respective horizontal fold line 94 to the basal edge 96 of a narrow flap 98. The panels 76, 24, 90, 98 have a collective inner edge 100 that is stepped-back from the hinge line 56, and a collective outer edge 102 that is coincident with the outer edge 104 of the outside right panel 26. The outer edge 102 of the inside right panel 24 is integrally hinged on a respective vertical fold line 106 to the inner edge 108 of a narrow outer boxing panel 110. The outer edge 112 of the outer boxing panel 110 is integrally hinged along a vertical fold line 114 to the basal edge 116 of a narrow flap 118. Four, short, oblique cuts or slots 120 arranged in a rectangular pattern are shown provided in the inside right panel 24, with a respective cut or slot generally forming an incomplete triangle with the respective panel edges at a respective corner of the panel 24. A thumb-access recess 121 is shown formed in the panel edge 100, about midway up the height thereof. As will be understood in the paper blank art, some of the panels and flaps may be integrally joined along other edges than the ones shown, yet produce a functionally substantially identical product. For instance, the panels 18 and 16 could be joined along respective lower edges 122, 124 rather than along respective upper edges 26, 29. In general, the boxing panels 76, 110 and 90 are equal in width and slightly narrower than the panel 52. Although the informational layout of the six panels is subject to some variation without departing from the principles of the invention, a typical layout is tabulated as follows: ______________________________________Panel Informational Content______________________________________16 inside left panel check book specimens 130; "shingles" of check book cover material specimens 132; and vignettes of other cover stock 134.18 outside left panel cover art 136 (printed).20 outside central panel specimen checks 138 (printed).22 outside central panel patent and copyright notice 140; space 142 for over print by bank, regional supplier or contact-person at printers.24 inside right panel check book cover styles and colors 144 (printed).26 outside right panel check book types 146 (printed).______________________________________ Beside the graphics and/or specimens on each panel, there may be provided textual material giving information about the various possibilities and/or style numbers and similar information. After the folds being shown in the process of being made in FIG. 10 are completed, the various facially confronting surfaces are glued or otherwise adhered together using conventional adhesive materials and techniques. In particular, the unglazed face 150 of the inside left panel is adhered to the unglazed face 152 of the outside left panel, and then the unglazed face 154 of the flap 34 is adhered to the glazed face 156 of the inside left panel marginally of the outer edge of the inside left panel thus creating a composite left panel glazed on front and back, with a triple thickness marginally of the outer edge thereof. The unglazed face 158 of the inside central panel is adhered to the unglazed face of the outside central panel, thus creating a composite central panel glazed on the front and back. The glazed outer faces 160, 162 of the flaps 98 and 118 are adhered to the unglazed face of the outside right panel, respectively marginally of the lower and outer edges thereof, thus creating an inwardly open, interiorly unglazed, exteriorly glazed slip case 164, in which e.g. a stock of unused order blanks may be kept in loose or pad form. The cutout 121 allows easy pullout of slipcase contents. Of course other materials could be kept in the slip case, such as more specimens of check stock. The sizes and thicknesses of the various materials, panels and flaps is such that when folded closed, as shown in FIGS. 7 and 8, the portfolio 200 of the invention is substantially rectangular prismatic in form. The panels are preferably laid-out in such a way that when the portfolio is presented to a customer in a closed condition, the outside left panel 18 constitutes its front cover, inviting the customer to open by swinging the left panel about its hinges 44, 46. This act exposes two panel sides to the viewer: the inside left panel 16, with its check book specimens and check book cover samples, and the outside right panel 26 with its check book styles. The next natural act is for the customer to open out the right panel. This act exposes two more panel sides to the viewer: the inside central panel ith its array of check designs and the inside right panel with its array of check book cover selection possibilities. In addition, this act exposes the open mouth of the order pad slip case, so that the order pad may be withdrawn and an order blank filled in by or for the customer. The order blank to be filled out may be temporarily superimposed on the inside right panel and its corners inserted through the cuts 120 so that the customer or bank employee may easily fill in the various choices of style, color and type and provide the other information requested on the form. Of course, the specific title and the example given in detail herein may for certain contemplated uses of the invention not be fully informative. For instance, the portfolio may be used as a marketing tool at the wholesale level, or may be used as a display, without being used for taking orders at all. Further, it may be used in combination with other marketing efforts. To that end, the cuts 120 may be used for mounting a sheet to feature a new product or service the user-bank or that the user-printer wishes to being to the customer's or potential customer's attention as a tie-in with the portfolio presentation. Thus, the title and examples are truly exemplary but are not exclusive characterizations, as will be understood by those skilled in the art. It should now be apparent that the checking account check and check book order-taking portfolio as described hereinabove, possesses each of the attributes set forth in the specification under the heading "Summary of the Invention" hereinbefore. Because it can be modified to some extent without departing from the principles thereof as they have been outlined and explained in this specification, the present invention should be understood as encompassing all such modifications as are within the spirit and scope of the following claims.
A kit, primarily for use in marketing customer supplies, e.g. checks, check books, and check book covers, which is the form of a three panel per side portfolio, including a pocket for order forms, clear plastic coating on one face of the portfolio blank which folds and is second to provide six panel faces of protected graphics, and a single layer in the integral hinge regions for compact folding.
Briefly summarize the invention's components and working principles as described in the document.
[ "BACKGROUND OF THE INVENTION In the security and safety-paper printing and marketing industry, particularly for checking account customer supplies for banks and similar institutions, the availability at each bank branch information or new account deck of customer supplies order-taking book or kit of some type has come to be an essential marketing tool, both for the bank and for the supplier.", "Traditionally, the books or kits have taken the form of a spiral-bound, ring-bound or loose-leaf book, with pages of suggestions, specimens and the like.", "SUMMARY OF THE INVENTION It is an object of the invention to provide a kit, primarily for use in marketing customer supplies, e.g. checks, check books, and check book covers, which is the form of a three panel per side portfolio, including a pocket for order forms, clear plastic coating on one face of the portfolio blank which folds and is secured to provide six panel faces of protected graphics, and a single layer in the integral hinge regions for compact folding.", "The principles of the invention will be further discussed with reference to the drawings wherein a preferred embodiment is shown.", "The specifics illustrated in the drawings are intended to exemplify, rather than limit, aspects of the invention as defined in the claims.", "BRIEF DESCRIPTION OF THE DRAWINGS In the drawings FIG. 1 is a perspective view of a checking account check and check book order-taking portfolio or similar article, in a partially opened condition;", "FIG. 2 is a top plan view thereof;", "FIG. 3 is a bottom plan view thereof;", "FIG. 4 is a rear elevational view thereof;", "FIG. 5 is an outer end elevational view of the left panel thereof;", "FIG. 6 is an outer end elevational view of the right panel thereof;", "FIG. 7 is a perspective view of said portfolio or similar article in a folded-closed condition, looking obliquely toward the lower right corner of the left panel thereof;", "and FIG. 8 is a perspective view thereof from a diagonally opposite vantage point, looking obliquely toward the upper left corner of the left panel thereof.", "FIG. 9 is a smaller scale plan view of the non-glazed side of the blank from which the portfolio is assembled;", "and FIG. 10 is a perspective view of the blank from the non-glazed side, showing all the folds partly made.", "DETAILED DESCRIPTION In FIG. 9 the blank 10 is shown having been die cut or similarly severed from a supply of preprinted paper board or similar file folder-weight stock, which is e.g. plastic coated on the printed side, in order to extend the life of the portfolio by reducing the potential that abrasion, or perspiration and the like due to handling will make the portfolio look less attractive or become shopworn and not have a desirable look of newness and freshness.", "The clear coating 12 applied over the printing 14 on the printed side, may be of exactly the prior art sort conventionally used on restaurant menus.", "The blank 10 includes six rectangular major panels.", "In the text, these are referred to assuming the following orientation: that the user has the portfolio before him or her in a partially open condition, i.e. as depicted in FIG. 1, so that the "inside"", "or "front"", "is facing the user and the "outside"", "or "back"", "(shown in FIG. 4) is directed away from the user.", "Accordingly, the panels are designated herein: inside left 16, outside left 18, inside central 20, outside central 22, inside right 24 and outside right 26.", "The upper edge 27 of the outside left panel 18 is integrally hinged on a respective horizontal fold line 28 to the upper edge 29 of the inside left panel 16.", "The outer edge 30 of the outside left panel 18 is integrally hinged on a respective vertical fold line 32 to the basal edge 33 of a narrow (e.g. inch wide) flap 34.", "The upper edge 36 of the outside central panel 22 is integrally hinged on a respective horizontal fold line 38 to the upper edge 40 of the inside central panel 20.", "Between the outside left panel 18 and the outside central panel 22 there is provided a first narrow spine panel 42 integrally hinged on respective vertical fold lines 44 and 46 to the right edge 48 of the outside left panel 18 and the left edge 50 of the outside central panel 22.", "Between the outside central panel 22 and the outside right panel 26 there is provided a second narrow spine panel 52 which typically is about half as broad as the first spine panel 42, and is integrally hinged on respective vertical fold lines 54 and 56 to the right edge 58 of the outside central panel 22 and the left edge 60 of the outside right panel.", "The inside left panel 16 is slightly narrower than the outside left panel 18, so that neither of its vertical side edges 62, 64 interferes with folding on the fold lines 32, 44.", "Likewise, the inside central panel 20 is slightly narrower than the outside central panel 22, so that neither of its vertical side edges 66, 68 interferes with folding on the fold lines 46, 54.", "The inside left and central panels 16 and 20 respectively are no longer than and at least approximately as long as the respective outside left and outside central panels 18 and 22.", "The upper edge 70 of the outside right panel 26 is integrally hinged on a respective horizontal fold line 72 to an outer edge 74 of an upper narrow boxing panel 76.", "The upper edge 78 of the inside right panel 24 is integrally hinged on a respective horizontal fold line 80 to the inner edge 82 of the upper boxing panel 76.", "The lower edge 84 of the inside right panel 24 is integrally hinged on a respective horizontal fold line 86 to the inner edge 88 of the lower boxing panel 90.", "The outer edge 92 of the lower boxing panel 90 is integrally hinged on a respective horizontal fold line 94 to the basal edge 96 of a narrow flap 98.", "The panels 76, 24, 90, 98 have a collective inner edge 100 that is stepped-back from the hinge line 56, and a collective outer edge 102 that is coincident with the outer edge 104 of the outside right panel 26.", "The outer edge 102 of the inside right panel 24 is integrally hinged on a respective vertical fold line 106 to the inner edge 108 of a narrow outer boxing panel 110.", "The outer edge 112 of the outer boxing panel 110 is integrally hinged along a vertical fold line 114 to the basal edge 116 of a narrow flap 118.", "Four, short, oblique cuts or slots 120 arranged in a rectangular pattern are shown provided in the inside right panel 24, with a respective cut or slot generally forming an incomplete triangle with the respective panel edges at a respective corner of the panel 24.", "A thumb-access recess 121 is shown formed in the panel edge 100, about midway up the height thereof.", "As will be understood in the paper blank art, some of the panels and flaps may be integrally joined along other edges than the ones shown, yet produce a functionally substantially identical product.", "For instance, the panels 18 and 16 could be joined along respective lower edges 122, 124 rather than along respective upper edges 26, 29.", "In general, the boxing panels 76, 110 and 90 are equal in width and slightly narrower than the panel 52.", "Although the informational layout of the six panels is subject to some variation without departing from the principles of the invention, a typical layout is tabulated as follows: ______________________________________Panel Informational Content______________________________________16 inside left panel check book specimens 130;", ""shingles"", "of check book cover material specimens 132;", "and vignettes of other cover stock 134.18 outside left panel cover art 136 (printed)[.", "].20 outside central panel specimen checks 138 (printed)[.", "].22 outside central panel patent and copyright notice 140;", "space 142 for over print by bank, regional supplier or contact-person at printers[.", "].24 inside right panel check book cover styles and colors 144 (printed)[.", "].26 outside right panel check book types 146 (printed).", "______________________________________ Beside the graphics and/or specimens on each panel, there may be provided textual material giving information about the various possibilities and/or style numbers and similar information.", "After the folds being shown in the process of being made in FIG. 10 are completed, the various facially confronting surfaces are glued or otherwise adhered together using conventional adhesive materials and techniques.", "In particular, the unglazed face 150 of the inside left panel is adhered to the unglazed face 152 of the outside left panel, and then the unglazed face 154 of the flap 34 is adhered to the glazed face 156 of the inside left panel marginally of the outer edge of the inside left panel thus creating a composite left panel glazed on front and back, with a triple thickness marginally of the outer edge thereof.", "The unglazed face 158 of the inside central panel is adhered to the unglazed face of the outside central panel, thus creating a composite central panel glazed on the front and back.", "The glazed outer faces 160, 162 of the flaps 98 and 118 are adhered to the unglazed face of the outside right panel, respectively marginally of the lower and outer edges thereof, thus creating an inwardly open, interiorly unglazed, exteriorly glazed slip case 164, in which e.g. a stock of unused order blanks may be kept in loose or pad form.", "The cutout 121 allows easy pullout of slipcase contents.", "Of course other materials could be kept in the slip case, such as more specimens of check stock.", "The sizes and thicknesses of the various materials, panels and flaps is such that when folded closed, as shown in FIGS. 7 and 8, the portfolio 200 of the invention is substantially rectangular prismatic in form.", "The panels are preferably laid-out in such a way that when the portfolio is presented to a customer in a closed condition, the outside left panel 18 constitutes its front cover, inviting the customer to open by swinging the left panel about its hinges 44, 46.", "This act exposes two panel sides to the viewer: the inside left panel 16, with its check book specimens and check book cover samples, and the outside right panel 26 with its check book styles.", "The next natural act is for the customer to open out the right panel.", "This act exposes two more panel sides to the viewer: the inside central panel ith its array of check designs and the inside right panel with its array of check book cover selection possibilities.", "In addition, this act exposes the open mouth of the order pad slip case, so that the order pad may be withdrawn and an order blank filled in by or for the customer.", "The order blank to be filled out may be temporarily superimposed on the inside right panel and its corners inserted through the cuts 120 so that the customer or bank employee may easily fill in the various choices of style, color and type and provide the other information requested on the form.", "Of course, the specific title and the example given in detail herein may for certain contemplated uses of the invention not be fully informative.", "For instance, the portfolio may be used as a marketing tool at the wholesale level, or may be used as a display, without being used for taking orders at all.", "Further, it may be used in combination with other marketing efforts.", "To that end, the cuts 120 may be used for mounting a sheet to feature a new product or service the user-bank or that the user-printer wishes to being to the customer's or potential customer's attention as a tie-in with the portfolio presentation.", "Thus, the title and examples are truly exemplary but are not exclusive characterizations, as will be understood by those skilled in the art.", "It should now be apparent that the checking account check and check book order-taking portfolio as described hereinabove, possesses each of the attributes set forth in the specification under the heading "Summary of the Invention"", "hereinbefore.", "Because it can be modified to some extent without departing from the principles thereof as they have been outlined and explained in this specification, the present invention should be understood as encompassing all such modifications as are within the spirit and scope of the following claims." ]
FIELD OF THE INVENTION The present invention relates to the field of high-speed optical communications, and more specifically to electroabsorption modulation methods and apparatus. BACKGROUND INFORMATION Semiconductor electroabsorption modulators (EAMs) offer the advantages of low drive voltage, small form factor, and integratability with active optical elements. EAM-integrated lasers are widely used in metro-distance communication networks. EAMs are also key building blocks for highly integrated photonic circuits. The low drive voltage requirement of EAMs is especially promising for emerging high bit-rate (>100 Gb/s) communications, where the wide-band electrical amplification required for driving lithium niobate modulators (LNMs) is difficult to achieve. In contrast to LNMs, which typically are operated using phase modulation combined with interferometric structures, EAMs have been used as single amplitude modulation elements. Considering the importance of phase shift keying (PSK) modulation, including quadrature phase shift keying (QPSK), and quadrature amplitude modulation (QAM) in high bit-rate, high spectral-efficiency transmission, it would be desirable to use EAMs for a wider range of modulation formats other than amplitude modulation. SUMMARY OF THE INVENTION The present invention is directed to modulating optical signals using electroabsorption in conjunction with an optical interferometer. In an exemplary embodiment, phase shift keying (PSK) modulation is performed using a polarization-sensitive electroabsorption modulator (EAM) operating interferometrically. The PSK modulation is achieved by interferometrically combining the transverse electric (TE) and transverse magnetic (TM) modes of an optical signal propagating through the EAM. In a further exemplary embodiment, interferometric operation of an EAM is used to perform amplitude shift keying (ASK) modulation, such as on-off keying (OOK). For ASK modulation, interferometric operation of an EAM provides significantly improved extinction ratio performance for the same drive voltage, or alternatively it allows EAMs to be operated at much lower drive voltages for a desired extinction ratio. The present invention can be used to enhance the electro-optic bandwidth of EAMs, overcoming the trade-off relationship between extinction ratio and bandwidth. In further exemplary embodiments, EAMs incorporated into an interferometer structure, such as a Mach-Zehnder interferometer (MZI). In one such embodiment, an EAM is included in each arm of an MZI with the outputs of the EAMs being interferometrically combined. Such EAM-MZI structures can be combined to provide various modulation formats, in accordance with the present invention. In addition to the aforementioned, the present invention can be used for a wide variety of modulation formats, including, for example, QPSK and QAM. The aforementioned and other features and aspects of the present invention are described in greater detail below. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an exemplary embodiment of an interferometric modulation device comprising an electroabsorption modulator (EAM) in accordance with the present invention. FIGS. 2A-2C graphically illustrate interferometric operation of an EAM in accordance with the present invention. FIG. 3 shows an exemplary embodiment of an EAM-Mach-Zehnder interferometer (EAM-MZI) structure in accordance with the present invention. FIGS. 4A and 4B illustrate OOK and PSK signals generated with the EAM-MZI structure of FIG. 3 . FIG. 5 shows an exemplary embodiment of an EAM-MZI structure incorporating a semiconductor optical amplifier (SOA), in accordance with the present invention. FIG. 6 shows an exemplary embodiment of a modulator incorporating multiple EAM-MZI structures, in accordance with the present invention. FIGS. 7A and 7B show eye diagrams of a PSK signal generated by an exemplary embodiment of a modulation device in accordance with the present invention, before and after demodulation, respectively. FIGS. 8A and 8B show eye diagrams of on-off keying (OOK) signals generated by an EAM without and with interferometric operation, respectively. FIG. 9 shows graphs of the extinction ratio and receiver sensitivity for OOK signals generated by an EAM with and without interferometric operation. DETAILED DESCRIPTION FIG. 1 is a block diagram of an exemplary embodiment of a system 100 comprising an electroabsorption modulator (EAM) operating interferometrically in accordance with the present invention. In the system 100 , a laser light having an electric field designated E L is launched via a polarization controller 110 into an EAM 120 . The launched laser light may be any suitable laser light and may be modulated or unmodulated, including, for example, a continuous wave (CW) laser or an optical pulse train. The polarization controller 110 controls the launch angle θ of the laser. The launch angle θ is the angle of the electric field E L of the laser with respect to the transverse electric (TE) axis of the EAM 120 . An analyzing polarizer 130 is arranged at the output of the EAM 120 with an orientation angle of φ with respect to the TE axis of the EAM 120 . FIG. 2A graphically illustrates the principle of operation of the above-described arrangement. The electric field E L is shown as a vector which is decomposed along the TE and transverse magnetic (TM) axes of the EAM 120 . The TE and TM components of the electric field E L are shown in FIG. 2A as the vectors E TE (t) and E TM (t), respectively. The TE and TM components E TE (t) and E TM (t) are projected onto the analyzing polarizer 130 , which interterferometrically combines the respective projections. The EAM 120 amplitude modulates the laser in accordance with a data stream (DATA). As the laser is modulated with data and its electric field E L varies with time, the TE and TM component fields E TE (t) and E TM (t) and their projections onto the analyzing polarizer 130 will vary accordingly, as shown along the t-axis in FIG. 2A by the traces 210 and 220 . As can be readily appreciated from FIG. 2A , the relative magnitudes and modulation depths of the two projected fields 210 , 220 can be adjusted by controlling the launch and analyzer orientation angles, θ and φ, respectively. EAMs based on quantum wells show preferential TE-polarization absorption unless the anisotropy is relieved by tensile strains. As shown in FIG. 2A , the TE modulation depth is substantially larger than the TM modulation depth. For example, a commercial EAM device such as the OKI OM5753C-30B has a TE modulation depth approximately 9 dB larger than the TM modulation depth for a 2V drive signal amplitude and a −1V bias voltage. As shown in FIGS. 2B and 2C , respectively, PSK modulation or amplitude shift keying (ASK) modulation, such as on-off keying (OOK), can be achieved by properly adjusting the angle parameters, θ and φ, which affect the TE and TM projections. Thus, while the “raw” modulation depths of the TE and TM modes are set by the properties of the EAM and the bias and drive voltages, the present invention makes it possible, by interferometric operation, to achieve PSK or improve the amplitude modulation depths, i.e. extinction ratio, by adjusting the angle parameters θ and φ. As shown in FIG. 2B , PSK modulation can be achieved when the mean values of the TM and TE projection fields 210 and 220 are roughly equalized. As shown in FIG. 2C , OOK modulation with an enhanced extinction ratio can be achieved when the low levels of the TE and TM projection fields 210 and 220 are equalized. In further exemplary embodiments, the operational principle of the present invention can be realized utilizing other arrangements, including, for example, a Mach-Zehnder interferometer (MZI) with an EAM in each arm, as shown in FIG. 3 . In addition to reduced polarization sensitivity, such an embodiment may be beneficial in reducing excess loss, as discussed below. As shown in FIG. 3 , a MZI 300 comprises a first EAM 301 in a first arm and a second EAM 302 in a second arm, with a phase shifter 305 arranged in the second arm, in line with the EAM 302 . (As can be appreciated, a phase shifter can be arranged in the first arm instead of the second arm, or in both arms, so long as the appropriate phase relationship between the two arms is provided.) The EAMs 301 and 302 are driven by respective drive signals, Drive Signal 1 and Drive Signal 2 . A CW laser is provided to the EAMs 301 , 302 via an input coupler (or splitter) 303 . The outputs of the EAMs 301 , 302 (via the phase shifter 305 ) are combined by an output coupler 304 . Various drive signal configurations may be employed depending on the type of modulation format, the specification of the EAMs, and the coupling ratio of the input and output couplers 303 , 304 . In a first such configuration, one of the EAM drive signals (e.g., Drive Signal 1 ) is the data signal to be modulated. The other EAM drive signal (e.g., Drive Signal 2 ) is a DC bias voltage which is selected so that the CW transmission through the corresponding EAM ( 302 ) cancels the low level of the modulated signal in the other EAM ( 301 ), as shown in FIG. 4A . In FIG. 4A , the dotted trace represents an NRZ-OOK modulated signal in the first EAM 301 , the dashed trace represents the CW transmission signal attenuated by the second EAM 302 and the solid trace represents the output signal resulting from the destructive interference of the aforementioned signals. Such a configuration provides an improvement in extinction ratio over OOK generated by an individual EAM operating conventionally. The DC bias voltage to be applied (as Drive Signal 2 ) will depend on the dynamic extinction ratio of the first EAM 301 and the coupling ratios of the couplers 303 , 304 . The coupling ratios are preferably selected to reduce the transmission loss of the EAM-MZI structure. Factors which affect the optimal coupling ratio include the raw extinction ratio of the first EAM 301 , the intended modulation format, and the insertion losses of the two EAMs. If the goal is to increase the extinction ratio of OOK, then the power splitting ratio of the input coupler 303 should be ε/(1+ε), where ε is the raw extinction ratio if the second EAM 302 has the same insertion loss as the first EAM 301 and no voltage is applied to the second EAM 302 . Other coupling ratios may be used if the second EAM 302 is to be biased to control the propagation loss. Because it may be difficult to know all of the device parameters in advance, a variable coupler may be advantageous. The coupling ratio can be fixed, however, and the extinction ratio optimized by adjusting the bias voltage to the second EAM 302 . This single data drive signal configuration can also be used to generate PSK signals by adjusting the DC bias voltage (Drive Signal 2 ) accordingly. In a second drive signal configuration, Drive Signal 1 is the data signal D and Drive Signal 2 is the complementary data signal D . This configuration can be used, for example, to generate Binary PSK signals (BPSK) with reduced optical loss. The signals in this driving configuration are shown in FIG. 4B in which the dotted trace represents the OOK signal output of the first EAM (driven by the data signal D), the dashed trace represents the OOK signal output of the second EAM (driven by the complementary data signal D ) and the solid trace represents the PSK signal resulting from the destructive interference of the two EAM output signals. This dual drive scheme reduces the optical loss by at least 6 dB in comparison to PSK generation with a single data drive signal. A comparison of FIGS. 2A and 2B with FIGS. 4A and 4B shows the benefit of the EAM-MZI structure in reducing the optical loss resulting from the destructive interference. For generating PSK, the arrangement represented by FIG. 4B is superior to that of FIG. 2B because at least 6 dB less optical power is subtracted during the destructive interference. Similarly, FIG. 4A is superior to FIG. 2C in generating extinction-enhanced OOK signals as less optical power is lost during the destructive interference. The destructive interference employed in generating signals in accordance with the principles of the present invention results in optical loss. This optical loss, however, can be compensated for by providing amplification, as in the exemplary device shown in FIG. 5 . In the device of FIG. 5 , a semiconductor optical amplifier (SOA) 510 is preferably integrated into an EAM-MZI device 500 to compensate for the aforementioned optical loss. In order to minimize the impact of any pattern dependence of the SOA, it is preferable to place the SOA at the output of the modulator (as shown) for PSK generation, or at the input of the modulator for OOK generation. The ability to readily integrate SOAs with the EAM-based modulators of the present invention is an advantage over other devices, such as lithium niobate modulators, for example. Although the foregoing description was made with reference to non-return-to-zero (NRZ) signal formats, the same optical modulators can also be used with RZ formats as well. An exemplary arrangement of obtaining the drive signal for RZ format generation consists of an electronic AND circuit, performing the Boolean operation between the NRZ data signal and a clock signal of the line rate. The product of the AND operation can be used to drive the EAM-MZI modulators to generate RZ-format signals. EAM-based modulators such as those of the present invention are better suited for employing such a technique than are lithium niobate modulators because of the low drive voltage as well as the optical transmission characteristic, which is highly nonlinear as a function of the drive voltage. At high bit rates, the Boolean AND operation tends to introduce signal distortion, especially for large amplitude signals. Lithium niobate modulators are more susceptible to such distortion due to their fairly linear transmission response with respect to the drive voltages. The generation of more complicated modulation formats can be achieved by combining multiple EAM-interferometer structures in accordance with the present invention. An exemplary embodiment of a modulator that can be used to generate QPSK signals is shown in FIG. 6 . The modulator shown in FIG. 6 comprises a first EAM-MZI structure 610 and a second EAM-MZI structure 620 arranged in an MZI structure 600 . The EAM-MZI structures 610 and 620 each comprises a π phase shifter 611 , 612 , respectively, and each is driven by a data signal and its complement (A, Ā and B, B , respectively) to generate corresponding BPSK modulated signals. The BPSK signals are combined to produce a QPSK signal by introducing a relative phase shift of π/2 between the two signals. Such a phase shift is provided by the phase shifter 625 . QPSK generation using EAM interferometers, such as by the exemplary embodiment of FIG. 6 , enjoys substantially reduced drive voltage requirements, thereby reducing the cost and power consumption of the drive electronics. The device of FIG. 6 can be used for generating other signal formats, including, for example, 8-QAM signals. To do so, one of the EAM-MZIs 610 , 620 (but not both) is effectively disabled for a bit period, such as by applying the same voltage to both drive signal inputs of the EAM-MZI to be disabled. The performance of exemplary embodiments of EAM-based interferometric devices in accordance with the present invention will now be described. In an exemplary embodiment of a device such as that of FIG. 1 , CW light with a wavelength of 1553 nm is used and its launch angle into the EAM ( 120 ) is controlled using an HP8169A polarization controller ( 110 ). The polarization of the output of the EAM is controlled using a paddle polarization controller and the output of the EAM is analyzed by a fiber-optic polarizer. The EAM has a 3-dB bandwidth of 30 GHz and the amplitude of the drive signal is 2.6 volts. FIG. 7A shows the electrical eye diagram of a 40-Gb/s PSK signal generated by such a system. FIG. 7B shows the eye diagram of the PSK signal after demodulation by a 25-ps delay interferometer. The demodulated signal was then electronically de-multiplexed and bit error rates (BER) were measured at 10 Gb/s after an erbium-doped fiber amplifier (EDFA) with a noise figure of 5.6 dB and an optical filter with 1-nm bandwidth. The receiver sensitivity at a BER of 10 −9 is −24.3 dBm. This is approximately 3 dB worse than that obtained with PSK generated using a lithium niobate modulator biased at a null. As evidenced in the demodulated eye diagram ( FIG. 7B ), the penalty is mostly due to the waveform distortion caused by the incomplete interference between the TE and TM fields, which have non-identical temporal shapes owing to the different responses of the two modes to the drive signal. With respect to the generation of ASK modulated signals, the extinction ratio of an ASK signal conventionally modulated by an EAM is related to the amplitude of the drive signal. Operation with a lower-voltage drive is preferable for reducing the power consumption and complexity of the driving electronics. FIG. 8A shows the electrical eye diagram of OOK signals obtained directly from an EAM operating conventionally and not in an interferometric mode. In this case, the maximum extinction ratio (ER) is achieved when the CW laser is aligned with the TE axis of the EAM, which in this case is 5.7 dB for a 1.1 V drive voltage. FIG. 7B shows a clear improvement in ER when operating the EAM in an interferometric mode with the angles θ and φ optimized. (For the exemplary data shown in FIG. 7B , the angles were 29 degrees.) The improved ER is measured to be 12.5 dB for the same drive voltage of 1.1 V. FIG. 9 shows the extinction ratio (ER) and receiver sensitivity (RS) as function of drive voltage, for a BER of 10 −9 , for OOK signals generated by an EAM operating non-interferometrically and interferometrically. The open circles and squares represent the ER and RS, respectively, for the non-interferometric EAM and the solid circles and squares represent the ER and RS, respectively, for the interferometric EAM. For non-interferometric operation, the best ER and RS are achieved when the input laser light is aligned with the TE axis of the EAM. With interferometric operation in accordance with the present invention, FIG. 9 shows an ER improvement of 8.7 dB and an RS improvement of 7 dB for a drive voltage of 0.8V. Advantageously, 0.8V, 40-Gb/s drive signals can be generated in accordance with the present invention, without using an electrical amplifier. It is understood that the above-described embodiments are illustrative of only a few of the possible specific embodiments which can represent applications of the invention. Numerous and varied other arrangements can be made by those skilled in the art without departing from the spirit and scope of the invention.
Methods and apparatus are described for modulating an optical signal using electroabsorption in conjunction with an optical interferometer. Phase-shift keying modulation can be achieved with lower amplitude modulator drive signals than conventional methods by splitting the signal to be modulated into multiple optical modes and interferometrically combining the modes after modulating at least one of the modes with an EAM. Using the present invention, the extinction ratio performance of ASK can be significantly improved for a given drive voltage or a desired extinction ratio can be achieved with a substantially lower drive voltage. Hence, the elecro-optic bandwidth of EAMs can be enhanced by overcoming the trade-off relationship between extinction ratio and bandwidth. Furthermore, the present invention can be used to generate other modulation formats, such as QPSK or QAM, with much lower drive voltages, thereby reducing the cost and power consumption of the high-speed drive electronics for the modulation.
Briefly describe the main invention outlined in the provided context.
[ "FIELD OF THE INVENTION The present invention relates to the field of high-speed optical communications, and more specifically to electroabsorption modulation methods and apparatus.", "BACKGROUND INFORMATION Semiconductor electroabsorption modulators (EAMs) offer the advantages of low drive voltage, small form factor, and integratability with active optical elements.", "EAM-integrated lasers are widely used in metro-distance communication networks.", "EAMs are also key building blocks for highly integrated photonic circuits.", "The low drive voltage requirement of EAMs is especially promising for emerging high bit-rate (>100 Gb/s) communications, where the wide-band electrical amplification required for driving lithium niobate modulators (LNMs) is difficult to achieve.", "In contrast to LNMs, which typically are operated using phase modulation combined with interferometric structures, EAMs have been used as single amplitude modulation elements.", "Considering the importance of phase shift keying (PSK) modulation, including quadrature phase shift keying (QPSK), and quadrature amplitude modulation (QAM) in high bit-rate, high spectral-efficiency transmission, it would be desirable to use EAMs for a wider range of modulation formats other than amplitude modulation.", "SUMMARY OF THE INVENTION The present invention is directed to modulating optical signals using electroabsorption in conjunction with an optical interferometer.", "In an exemplary embodiment, phase shift keying (PSK) modulation is performed using a polarization-sensitive electroabsorption modulator (EAM) operating interferometrically.", "The PSK modulation is achieved by interferometrically combining the transverse electric (TE) and transverse magnetic (TM) modes of an optical signal propagating through the EAM.", "In a further exemplary embodiment, interferometric operation of an EAM is used to perform amplitude shift keying (ASK) modulation, such as on-off keying (OOK).", "For ASK modulation, interferometric operation of an EAM provides significantly improved extinction ratio performance for the same drive voltage, or alternatively it allows EAMs to be operated at much lower drive voltages for a desired extinction ratio.", "The present invention can be used to enhance the electro-optic bandwidth of EAMs, overcoming the trade-off relationship between extinction ratio and bandwidth.", "In further exemplary embodiments, EAMs incorporated into an interferometer structure, such as a Mach-Zehnder interferometer (MZI).", "In one such embodiment, an EAM is included in each arm of an MZI with the outputs of the EAMs being interferometrically combined.", "Such EAM-MZI structures can be combined to provide various modulation formats, in accordance with the present invention.", "In addition to the aforementioned, the present invention can be used for a wide variety of modulation formats, including, for example, QPSK and QAM.", "The aforementioned and other features and aspects of the present invention are described in greater detail below.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an exemplary embodiment of an interferometric modulation device comprising an electroabsorption modulator (EAM) in accordance with the present invention.", "FIGS. 2A-2C graphically illustrate interferometric operation of an EAM in accordance with the present invention.", "FIG. 3 shows an exemplary embodiment of an EAM-Mach-Zehnder interferometer (EAM-MZI) structure in accordance with the present invention.", "FIGS. 4A and 4B illustrate OOK and PSK signals generated with the EAM-MZI structure of FIG. 3 .", "FIG. 5 shows an exemplary embodiment of an EAM-MZI structure incorporating a semiconductor optical amplifier (SOA), in accordance with the present invention.", "FIG. 6 shows an exemplary embodiment of a modulator incorporating multiple EAM-MZI structures, in accordance with the present invention.", "FIGS. 7A and 7B show eye diagrams of a PSK signal generated by an exemplary embodiment of a modulation device in accordance with the present invention, before and after demodulation, respectively.", "FIGS. 8A and 8B show eye diagrams of on-off keying (OOK) signals generated by an EAM without and with interferometric operation, respectively.", "FIG. 9 shows graphs of the extinction ratio and receiver sensitivity for OOK signals generated by an EAM with and without interferometric operation.", "DETAILED DESCRIPTION FIG. 1 is a block diagram of an exemplary embodiment of a system 100 comprising an electroabsorption modulator (EAM) operating interferometrically in accordance with the present invention.", "In the system 100 , a laser light having an electric field designated E L is launched via a polarization controller 110 into an EAM 120 .", "The launched laser light may be any suitable laser light and may be modulated or unmodulated, including, for example, a continuous wave (CW) laser or an optical pulse train.", "The polarization controller 110 controls the launch angle θ of the laser.", "The launch angle θ is the angle of the electric field E L of the laser with respect to the transverse electric (TE) axis of the EAM 120 .", "An analyzing polarizer 130 is arranged at the output of the EAM 120 with an orientation angle of φ with respect to the TE axis of the EAM 120 .", "FIG. 2A graphically illustrates the principle of operation of the above-described arrangement.", "The electric field E L is shown as a vector which is decomposed along the TE and transverse magnetic (TM) axes of the EAM 120 .", "The TE and TM components of the electric field E L are shown in FIG. 2A as the vectors E TE (t) and E TM (t), respectively.", "The TE and TM components E TE (t) and E TM (t) are projected onto the analyzing polarizer 130 , which interterferometrically combines the respective projections.", "The EAM 120 amplitude modulates the laser in accordance with a data stream (DATA).", "As the laser is modulated with data and its electric field E L varies with time, the TE and TM component fields E TE (t) and E TM (t) and their projections onto the analyzing polarizer 130 will vary accordingly, as shown along the t-axis in FIG. 2A by the traces 210 and 220 .", "As can be readily appreciated from FIG. 2A , the relative magnitudes and modulation depths of the two projected fields 210 , 220 can be adjusted by controlling the launch and analyzer orientation angles, θ and φ, respectively.", "EAMs based on quantum wells show preferential TE-polarization absorption unless the anisotropy is relieved by tensile strains.", "As shown in FIG. 2A , the TE modulation depth is substantially larger than the TM modulation depth.", "For example, a commercial EAM device such as the OKI OM5753C-30B has a TE modulation depth approximately 9 dB larger than the TM modulation depth for a 2V drive signal amplitude and a −1V bias voltage.", "As shown in FIGS. 2B and 2C , respectively, PSK modulation or amplitude shift keying (ASK) modulation, such as on-off keying (OOK), can be achieved by properly adjusting the angle parameters, θ and φ, which affect the TE and TM projections.", "Thus, while the “raw”", "modulation depths of the TE and TM modes are set by the properties of the EAM and the bias and drive voltages, the present invention makes it possible, by interferometric operation, to achieve PSK or improve the amplitude modulation depths, i.e. extinction ratio, by adjusting the angle parameters θ and φ.", "As shown in FIG. 2B , PSK modulation can be achieved when the mean values of the TM and TE projection fields 210 and 220 are roughly equalized.", "As shown in FIG. 2C , OOK modulation with an enhanced extinction ratio can be achieved when the low levels of the TE and TM projection fields 210 and 220 are equalized.", "In further exemplary embodiments, the operational principle of the present invention can be realized utilizing other arrangements, including, for example, a Mach-Zehnder interferometer (MZI) with an EAM in each arm, as shown in FIG. 3 .", "In addition to reduced polarization sensitivity, such an embodiment may be beneficial in reducing excess loss, as discussed below.", "As shown in FIG. 3 , a MZI 300 comprises a first EAM 301 in a first arm and a second EAM 302 in a second arm, with a phase shifter 305 arranged in the second arm, in line with the EAM 302 .", "(As can be appreciated, a phase shifter can be arranged in the first arm instead of the second arm, or in both arms, so long as the appropriate phase relationship between the two arms is provided.) The EAMs 301 and 302 are driven by respective drive signals, Drive Signal 1 and Drive Signal 2 .", "A CW laser is provided to the EAMs 301 , 302 via an input coupler (or splitter) 303 .", "The outputs of the EAMs 301 , 302 (via the phase shifter 305 ) are combined by an output coupler 304 .", "Various drive signal configurations may be employed depending on the type of modulation format, the specification of the EAMs, and the coupling ratio of the input and output couplers 303 , 304 .", "In a first such configuration, one of the EAM drive signals (e.g., Drive Signal 1 ) is the data signal to be modulated.", "The other EAM drive signal (e.g., Drive Signal 2 ) is a DC bias voltage which is selected so that the CW transmission through the corresponding EAM ( 302 ) cancels the low level of the modulated signal in the other EAM ( 301 ), as shown in FIG. 4A .", "In FIG. 4A , the dotted trace represents an NRZ-OOK modulated signal in the first EAM 301 , the dashed trace represents the CW transmission signal attenuated by the second EAM 302 and the solid trace represents the output signal resulting from the destructive interference of the aforementioned signals.", "Such a configuration provides an improvement in extinction ratio over OOK generated by an individual EAM operating conventionally.", "The DC bias voltage to be applied (as Drive Signal 2 ) will depend on the dynamic extinction ratio of the first EAM 301 and the coupling ratios of the couplers 303 , 304 .", "The coupling ratios are preferably selected to reduce the transmission loss of the EAM-MZI structure.", "Factors which affect the optimal coupling ratio include the raw extinction ratio of the first EAM 301 , the intended modulation format, and the insertion losses of the two EAMs. If the goal is to increase the extinction ratio of OOK, then the power splitting ratio of the input coupler 303 should be ε/(1+ε), where ε is the raw extinction ratio if the second EAM 302 has the same insertion loss as the first EAM 301 and no voltage is applied to the second EAM 302 .", "Other coupling ratios may be used if the second EAM 302 is to be biased to control the propagation loss.", "Because it may be difficult to know all of the device parameters in advance, a variable coupler may be advantageous.", "The coupling ratio can be fixed, however, and the extinction ratio optimized by adjusting the bias voltage to the second EAM 302 .", "This single data drive signal configuration can also be used to generate PSK signals by adjusting the DC bias voltage (Drive Signal 2 ) accordingly.", "In a second drive signal configuration, Drive Signal 1 is the data signal D and Drive Signal 2 is the complementary data signal D .", "This configuration can be used, for example, to generate Binary PSK signals (BPSK) with reduced optical loss.", "The signals in this driving configuration are shown in FIG. 4B in which the dotted trace represents the OOK signal output of the first EAM (driven by the data signal D), the dashed trace represents the OOK signal output of the second EAM (driven by the complementary data signal D ) and the solid trace represents the PSK signal resulting from the destructive interference of the two EAM output signals.", "This dual drive scheme reduces the optical loss by at least 6 dB in comparison to PSK generation with a single data drive signal.", "A comparison of FIGS. 2A and 2B with FIGS. 4A and 4B shows the benefit of the EAM-MZI structure in reducing the optical loss resulting from the destructive interference.", "For generating PSK, the arrangement represented by FIG. 4B is superior to that of FIG. 2B because at least 6 dB less optical power is subtracted during the destructive interference.", "Similarly, FIG. 4A is superior to FIG. 2C in generating extinction-enhanced OOK signals as less optical power is lost during the destructive interference.", "The destructive interference employed in generating signals in accordance with the principles of the present invention results in optical loss.", "This optical loss, however, can be compensated for by providing amplification, as in the exemplary device shown in FIG. 5 .", "In the device of FIG. 5 , a semiconductor optical amplifier (SOA) 510 is preferably integrated into an EAM-MZI device 500 to compensate for the aforementioned optical loss.", "In order to minimize the impact of any pattern dependence of the SOA, it is preferable to place the SOA at the output of the modulator (as shown) for PSK generation, or at the input of the modulator for OOK generation.", "The ability to readily integrate SOAs with the EAM-based modulators of the present invention is an advantage over other devices, such as lithium niobate modulators, for example.", "Although the foregoing description was made with reference to non-return-to-zero (NRZ) signal formats, the same optical modulators can also be used with RZ formats as well.", "An exemplary arrangement of obtaining the drive signal for RZ format generation consists of an electronic AND circuit, performing the Boolean operation between the NRZ data signal and a clock signal of the line rate.", "The product of the AND operation can be used to drive the EAM-MZI modulators to generate RZ-format signals.", "EAM-based modulators such as those of the present invention are better suited for employing such a technique than are lithium niobate modulators because of the low drive voltage as well as the optical transmission characteristic, which is highly nonlinear as a function of the drive voltage.", "At high bit rates, the Boolean AND operation tends to introduce signal distortion, especially for large amplitude signals.", "Lithium niobate modulators are more susceptible to such distortion due to their fairly linear transmission response with respect to the drive voltages.", "The generation of more complicated modulation formats can be achieved by combining multiple EAM-interferometer structures in accordance with the present invention.", "An exemplary embodiment of a modulator that can be used to generate QPSK signals is shown in FIG. 6 .", "The modulator shown in FIG. 6 comprises a first EAM-MZI structure 610 and a second EAM-MZI structure 620 arranged in an MZI structure 600 .", "The EAM-MZI structures 610 and 620 each comprises a π phase shifter 611 , 612 , respectively, and each is driven by a data signal and its complement (A, Ā and B, B , respectively) to generate corresponding BPSK modulated signals.", "The BPSK signals are combined to produce a QPSK signal by introducing a relative phase shift of π/2 between the two signals.", "Such a phase shift is provided by the phase shifter 625 .", "QPSK generation using EAM interferometers, such as by the exemplary embodiment of FIG. 6 , enjoys substantially reduced drive voltage requirements, thereby reducing the cost and power consumption of the drive electronics.", "The device of FIG. 6 can be used for generating other signal formats, including, for example, 8-QAM signals.", "To do so, one of the EAM-MZIs 610 , 620 (but not both) is effectively disabled for a bit period, such as by applying the same voltage to both drive signal inputs of the EAM-MZI to be disabled.", "The performance of exemplary embodiments of EAM-based interferometric devices in accordance with the present invention will now be described.", "In an exemplary embodiment of a device such as that of FIG. 1 , CW light with a wavelength of 1553 nm is used and its launch angle into the EAM ( 120 ) is controlled using an HP8169A polarization controller ( 110 ).", "The polarization of the output of the EAM is controlled using a paddle polarization controller and the output of the EAM is analyzed by a fiber-optic polarizer.", "The EAM has a 3-dB bandwidth of 30 GHz and the amplitude of the drive signal is 2.6 volts.", "FIG. 7A shows the electrical eye diagram of a 40-Gb/s PSK signal generated by such a system.", "FIG. 7B shows the eye diagram of the PSK signal after demodulation by a 25-ps delay interferometer.", "The demodulated signal was then electronically de-multiplexed and bit error rates (BER) were measured at 10 Gb/s after an erbium-doped fiber amplifier (EDFA) with a noise figure of 5.6 dB and an optical filter with 1-nm bandwidth.", "The receiver sensitivity at a BER of 10 −9 is −24.3 dBm.", "This is approximately 3 dB worse than that obtained with PSK generated using a lithium niobate modulator biased at a null.", "As evidenced in the demodulated eye diagram ( FIG. 7B ), the penalty is mostly due to the waveform distortion caused by the incomplete interference between the TE and TM fields, which have non-identical temporal shapes owing to the different responses of the two modes to the drive signal.", "With respect to the generation of ASK modulated signals, the extinction ratio of an ASK signal conventionally modulated by an EAM is related to the amplitude of the drive signal.", "Operation with a lower-voltage drive is preferable for reducing the power consumption and complexity of the driving electronics.", "FIG. 8A shows the electrical eye diagram of OOK signals obtained directly from an EAM operating conventionally and not in an interferometric mode.", "In this case, the maximum extinction ratio (ER) is achieved when the CW laser is aligned with the TE axis of the EAM, which in this case is 5.7 dB for a 1.1 V drive voltage.", "FIG. 7B shows a clear improvement in ER when operating the EAM in an interferometric mode with the angles θ and φ optimized.", "(For the exemplary data shown in FIG. 7B , the angles were 29 degrees.) The improved ER is measured to be 12.5 dB for the same drive voltage of 1.1 V. FIG. 9 shows the extinction ratio (ER) and receiver sensitivity (RS) as function of drive voltage, for a BER of 10 −9 , for OOK signals generated by an EAM operating non-interferometrically and interferometrically.", "The open circles and squares represent the ER and RS, respectively, for the non-interferometric EAM and the solid circles and squares represent the ER and RS, respectively, for the interferometric EAM.", "For non-interferometric operation, the best ER and RS are achieved when the input laser light is aligned with the TE axis of the EAM.", "With interferometric operation in accordance with the present invention, FIG. 9 shows an ER improvement of 8.7 dB and an RS improvement of 7 dB for a drive voltage of 0.8V.", "Advantageously, 0.8V, 40-Gb/s drive signals can be generated in accordance with the present invention, without using an electrical amplifier.", "It is understood that the above-described embodiments are illustrative of only a few of the possible specific embodiments which can represent applications of the invention.", "Numerous and varied other arrangements can be made by those skilled in the art without departing from the spirit and scope of the invention." ]
FIELD OF THE INVENTION [0001] The present invention relates to the sphere of high-pressure pipes intended to equip an oil well or an oil drilling and/or production installation, notably offshore. BACKGROUND OF THE INVENTION [0002] Oil is produced from an offshore reservoir using a pipe generally referred to as riser, which allows the wellhead installed at the sea bottom to be connected to the sea surface. The riser is an extension of the tubing carrying the oil from the well bottom to the wellhead. The riser is provided with at least two auxiliary lines called kill line and choke line, whose main function is to establish a hydraulic connection between the sea surface and the wellhead at the sea bottom. More particularly, these auxiliary lines allow to supply the well with fluid by circulating below the closed blowout preventer, and/or to discharge a fluid from the well, without passing through the inside of the riser. The fluid conveyed, resulting from an influx in an underground reservoir, can circulate at a pressure of 700 bars. [0003] In general, the auxiliary lines and the riser are each made from an assembly of tube elements. In order to minimize the number of connections on a riser, the greatest possible tube element length is selected. However, tube handling operations, notably upon mounting and dismantling of the riser, require limitation of the tubes length to an interval ranging between about 20 and 30 meters. In order to be able to readily and simultaneously carry out mounting of the riser and of the auxiliary lines, the length of the tubes that make up the auxiliary lines is substantially equal to the length of the tubes that make up the riser, i.e. a length ranging between about 20 and 30 meters. [0004] The present invention proposes making auxiliary lines from a pipe element assembly consisting of hooped tubes so as to reduce the weight to which the riser is subjected. However, hooping of an at least 20-m long pipe element requires bulky, sophisticated and therefore expensive machines. [0005] The present invention therefore proposes making an auxiliary line element from an assembly of several hooped tube sections, each pipe element having a length approximately greater than or equal to 20 meters. In particular, the invention provides an embodiment for connection means between the hooped tube sections allowing to obtain an approximately 20-m long pipe element. SUMMARY OF THE INVENTION [0006] The present invention thus relates to a high-pressure pipe element comprising at least two hooped tube sections connected by connection means that meet the mechanical strength and pressure resistance requirements relative to a hooped tube section. [0007] The connection means can comprise an intermediate part screwed between the two sections, seal means, locking means for fastening the sections on said intermediate part. [0008] The intermediate connecting part can be a tube whose outside diameter is smaller than or at most equal to the outside diameter of the hooped tube sections. [0009] The locking means comprise at least one U-shaped part intended to block any longitudinal play between the sections and the intermediate part. Each edge of the U-shaped part can be inserted in a groove machined around each end of a hooped tube section, and the U can be fastened to the intermediate connecting part by the bottom of the U. [0010] The pipe element according to the present invention can consist of four approximately 4-m long sections and of two approximately 2.5-m long sections. [0011] The pipe element according to the present invention can be used to make an auxiliary line of a drilling riser, and the auxiliary line can be a kill line, a choke line, a booster line or a mud return line. BRIEF DESCRIPTION OF THE DRAWINGS [0012] Other features and advantages of the invention will be clear from reading the description hereafter of a non limitative embodiment example, with reference to the accompanying drawings wherein: [0013] [0013]FIG. 1 diagrammatically shows a partial cross-sectional view of a connection between two hooped tubes, [0014] [0014]FIG. 2 is a cross-sectional view of an end of a hooped tube, [0015] [0015]FIG. 3 shows an intermediate connecting part, [0016] [0016]FIG. 4 is a perspective view of a U-shaped fastening means, [0017] [0017]FIG. 5 shows a pipe element consisting of hooped tubes connected according to the invention. DETAILED DESCRIPTION [0018] [0018]FIG. 1 shows the connection means of a pipe element according to the invention. The pipe element according to the invention consists of at least two hooped tubes 1 and 2 connected by means of an intermediate connecting part 3 and of U-shaped locking means or pipe bracket 4 . [0019] [0019]FIG. 2 shows the identical end of hooped tubes 1 and 2 which cooperates with intermediate connecting part 3 . The outer surface of the tube end comprises a groove 21 , or slot, machined perpendicular to the axis of the tube. Starting from the end of the tube, the inner surface of the tube comprises a first smooth surface 22 followed by a thread 23 ending in bore 24 . Inside diameter D 2 of the tube, in the vicinity of the thread, is smaller than diameter D 1 in the vicinity of smooth surface 22 . Inside diameter D 3 of the tube in the vicinity of surface 24 is generally smaller than or equal to diameter D 2 in the vicinity of thread 23 . Reinforcing elements can be wound around the outer surface of tubes 1 and 2 , except around groove 21 , so as to form hooping layer 25 . The outer surface of hooping layer 25 can be a cylinder of diameter D 7 . [0020] The connecting principle consists in using an intermediate part screwed onto the two ends of the hooped tubes with a sealing function and locking means for fastening the three parts together. The walls of the three parts have to be such that they meet the mechanical requirements, notably the internal pressure resistance. [0021] [0021]FIG. 3 shows intermediate connecting part 3 . Connecting part 3 is a tube of inside diameter D 4 and of outside diameter D 5 , and it comprises a central collar or shoulder 33 of diameter D 6 . Connecting part 3 stretches for example over an axial length of about 330 mm. Outside diameter D 5 is substantially equal to or slightly smaller than inside diameter D 1 of the end of tube 1 or 2 in the vicinity of first smooth surface 22 . Threads 31 and 32 are machined on the outer surface at both ends of connecting part 3 . The outside diameter of part 3 in the vicinity of threads 31 and 32 and the characteristics of threads 31 and 32 are so selected that threads 31 and 32 can respectively cooperate with box threads 23 of tubes 1 and 2 . At the centre of connecting part 3 , the outer surface of the tube comprises a shoulder 33 , i.e. a part in the middle of connecting element 3 has an outside diameter D 6 that is larger than diameter D 5 of connecting part 3 . The diameter D 6 of shoulder 33 is substantially constant. The shoulder can for example stretch over an axial length of about 40 mm. At each axial end of shoulder 33 , a wall 38 connects the outer surface of shoulder 33 of diameter D 6 to the tube of diameter D 5 . The two walls 38 can be substantially perpendicular to the axis of connecting part 3 . On the outer surface of shoulder 33 , grooves 34 are machined parallel to the axis of connecting part 3 . Connecting part 3 can for example comprise four grooves 34 evenly distributed on the outer circumference of shoulder 33 . At the bottom of each groove 34 , two blind holes 35 are pierced in the radial direction of connecting part 3 . Holes 35 are tapped. On the outer surface of connecting part 3 , two slots 36 are machined between shoulder 33 and thread 31 , and two slots 37 are machined between shoulder 33 and thread 32 . [0022] [0022]FIG. 4 shows a locking means in form of a pipe bracket 4 . The bracket is U-shaped, i.e. a bracket 4 consists of a base 40 (which forms the bottom of the U) and of two legs, or edge, 41 and 42 (which form the two free branches of the U). Base 40 has the shape of a plate of width l, of length L and of thickness e. Legs 41 and 42 form, in a perpendicular direction, the extension of base 40 in the direction of its length. Thus, legs 41 and 42 can have a thickness and a width substantially equal to thickness e and width l of base 40 . The thickness e of base 40 is pierced with two holes 43 . Preferably, width l of bracket 4 is selected substantially equal to the width of grooves 34 of connecting element 3 . Thickness e of legs 41 and 42 is preferably selected substantially equal to the width of grooves 21 of tubes 1 and 2 . [0023] With reference to FIG. 1, connection of hooped tubes 1 and 2 by means of intermediate connecting part 3 and of brackets 4 is carried out as follows: [0024] a seal means 10 is arranged in each slot 36 of connecting part 3 . Seal means 10 can be, for example, doughnut rings made from an elastomer. Other types of composite joints can also be used; [0025] intermediate connecting part 3 is screwed on in the end of tube 1 . Pin thread 31 of connecting element 3 is screwed onto box thread 23 of tube 1 . Connecting part 3 can be screwed on in the end of tube 1 until the end of tube 1 rests against a wall 38 of shoulder 33 of connecting element 3 . Connecting part 3 being screwed in the end of tube 1 , surface 22 of tube 1 faces slots 36 comprising seal means 10 so that the link between tube 1 and intermediate connecting part 3 is sealed; [0026] a seal means 10 is arranged in each slot 37 of intermediate connecting part 3 ; [0027] the end of tube 2 is screwed onto connecting part 3 . Pin thread 32 of connecting part 3 is screwed onto box thread 23 of tube 2 . Tube 2 can be screwed onto connecting element 3 until the end of tube 2 rests against a wall 38 of shoulder 33 of connecting part 3 . The end of tube 2 being screwed on connecting part 3 , surface 22 of tube 2 faces slots 37 comprising seal means 10 so that the link between intermediate connecting part 3 and tube 2 is sealed; [0028] brackets 4 are placed in grooves 34 . Legs 41 and 42 respectively fit into grooves 21 of tubes 1 and 2 . Thus, brackets 4 prevent axial displacement of each tube 1 and 2 in relation to intermediate part 3 , and consequently prevent the assembly from unscrewing; [0029] screws 11 are inserted into each hole 43 of brackets 4 and each thread 35 of connecting part 3 so as to hold brackets 4 in grooves 34 , and legs 41 and 42 in grooves 21 (in FIG. 1, only one screw 11 is shown). [0030] Connection can be performed without applying a makeup torque when screwing tubes 1 and 2 onto connecting element 3 . Tubes 1 and 2 resting against connecting element 3 and installing brackets 4 can be sufficient to provide the connection. [0031] Preferably, the geometry of tubes 1 , 2 , of intermediate connecting part 3 , of brackets 4 , diameter D 6 of the outer surface of shoulder 33 and thickness e of brackets 4 are so selected that the connection according to the present invention is inscribed in a cylinder of diameter D 7 (diameter D 7 being the outside diameter of hooping layer 25 ). Thus, the hooped tubes connected according to the present invention can be used without taking account of the connection. In particular, this feature is advantageous for storing pipe elements made of connected hooped tubes because the bearing surfaces are on the hooped lengths and not localized on the connections. [0032] In FIG. 5, the inside diameter of connecting zones 57 and 58 at the ends of a pipe element can be smaller than the inside diameter of tubes 51 to 56 . Preferably, inside diameter D 4 of connecting part 3 is so selected as to be larger than the smallest inside diameter of the connecting zones. [0033] The connecting means are so designed that the mechanical strength of the pipe element is at least equal to the strength of a hooped tube section. Furthermore, the resistance to the internal pressure, the working pressure, the test pressure, or the burst pressure of the pipe element made of hooped tube sections is identical or at least equal to the pressure resistance of a hooped tube section. It is clear that, for these conditions to be met, the inside diameter of the intermediate part is slightly smaller than the inside diameter of a hooped tube section. But the length of the intermediate part is short in relation to the length of a hooped tube section, which does practically not increase the pressure drops during circulation. [0034] [0034]FIG. 5 shows a pipe element made of hooped tubes 50 according to the invention. The element consists of six sections 51 to 56 . Sections 51 to 56 are hooped tubes. The length of four of the six hooped tubes 51 to 56 is about 4 meters. The length of two of the six hooped tubes 51 to 56 is about 2.5 meters. The pipe element according to the invention stretches over a length of about 21 meters. Hooped tube sections 51 to 56 are connected by means of intermediate connecting parts 3 described above. Section 51 at one end of pipe element 50 has a connecting zone 57 which can cooperate with connecting zone 58 of section 56 at the other end of another pipe element 50 .
The present invention relates to a high-pressure pipe element consisting of hooped tube sections for making lines referred to as kill lines and choke lines that equip oil drilling installations, notably offshore. The element consists of several hooped tube sections ( 51 to 56 ) connected by means of connecting parts ( 3 ).
Summarize the key points of the given patent document.
[ "FIELD OF THE INVENTION [0001] The present invention relates to the sphere of high-pressure pipes intended to equip an oil well or an oil drilling and/or production installation, notably offshore.", "BACKGROUND OF THE INVENTION [0002] Oil is produced from an offshore reservoir using a pipe generally referred to as riser, which allows the wellhead installed at the sea bottom to be connected to the sea surface.", "The riser is an extension of the tubing carrying the oil from the well bottom to the wellhead.", "The riser is provided with at least two auxiliary lines called kill line and choke line, whose main function is to establish a hydraulic connection between the sea surface and the wellhead at the sea bottom.", "More particularly, these auxiliary lines allow to supply the well with fluid by circulating below the closed blowout preventer, and/or to discharge a fluid from the well, without passing through the inside of the riser.", "The fluid conveyed, resulting from an influx in an underground reservoir, can circulate at a pressure of 700 bars.", "[0003] In general, the auxiliary lines and the riser are each made from an assembly of tube elements.", "In order to minimize the number of connections on a riser, the greatest possible tube element length is selected.", "However, tube handling operations, notably upon mounting and dismantling of the riser, require limitation of the tubes length to an interval ranging between about 20 and 30 meters.", "In order to be able to readily and simultaneously carry out mounting of the riser and of the auxiliary lines, the length of the tubes that make up the auxiliary lines is substantially equal to the length of the tubes that make up the riser, i.e. a length ranging between about 20 and 30 meters.", "[0004] The present invention proposes making auxiliary lines from a pipe element assembly consisting of hooped tubes so as to reduce the weight to which the riser is subjected.", "However, hooping of an at least 20-m long pipe element requires bulky, sophisticated and therefore expensive machines.", "[0005] The present invention therefore proposes making an auxiliary line element from an assembly of several hooped tube sections, each pipe element having a length approximately greater than or equal to 20 meters.", "In particular, the invention provides an embodiment for connection means between the hooped tube sections allowing to obtain an approximately 20-m long pipe element.", "SUMMARY OF THE INVENTION [0006] The present invention thus relates to a high-pressure pipe element comprising at least two hooped tube sections connected by connection means that meet the mechanical strength and pressure resistance requirements relative to a hooped tube section.", "[0007] The connection means can comprise an intermediate part screwed between the two sections, seal means, locking means for fastening the sections on said intermediate part.", "[0008] The intermediate connecting part can be a tube whose outside diameter is smaller than or at most equal to the outside diameter of the hooped tube sections.", "[0009] The locking means comprise at least one U-shaped part intended to block any longitudinal play between the sections and the intermediate part.", "Each edge of the U-shaped part can be inserted in a groove machined around each end of a hooped tube section, and the U can be fastened to the intermediate connecting part by the bottom of the U. [0010] The pipe element according to the present invention can consist of four approximately 4-m long sections and of two approximately 2.5-m long sections.", "[0011] The pipe element according to the present invention can be used to make an auxiliary line of a drilling riser, and the auxiliary line can be a kill line, a choke line, a booster line or a mud return line.", "BRIEF DESCRIPTION OF THE DRAWINGS [0012] Other features and advantages of the invention will be clear from reading the description hereafter of a non limitative embodiment example, with reference to the accompanying drawings wherein: [0013] [0013 ]FIG. 1 diagrammatically shows a partial cross-sectional view of a connection between two hooped tubes, [0014] [0014 ]FIG. 2 is a cross-sectional view of an end of a hooped tube, [0015] [0015 ]FIG. 3 shows an intermediate connecting part, [0016] [0016 ]FIG. 4 is a perspective view of a U-shaped fastening means, [0017] [0017 ]FIG. 5 shows a pipe element consisting of hooped tubes connected according to the invention.", "DETAILED DESCRIPTION [0018] [0018 ]FIG. 1 shows the connection means of a pipe element according to the invention.", "The pipe element according to the invention consists of at least two hooped tubes 1 and 2 connected by means of an intermediate connecting part 3 and of U-shaped locking means or pipe bracket 4 .", "[0019] [0019 ]FIG. 2 shows the identical end of hooped tubes 1 and 2 which cooperates with intermediate connecting part 3 .", "The outer surface of the tube end comprises a groove 21 , or slot, machined perpendicular to the axis of the tube.", "Starting from the end of the tube, the inner surface of the tube comprises a first smooth surface 22 followed by a thread 23 ending in bore 24 .", "Inside diameter D 2 of the tube, in the vicinity of the thread, is smaller than diameter D 1 in the vicinity of smooth surface 22 .", "Inside diameter D 3 of the tube in the vicinity of surface 24 is generally smaller than or equal to diameter D 2 in the vicinity of thread 23 .", "Reinforcing elements can be wound around the outer surface of tubes 1 and 2 , except around groove 21 , so as to form hooping layer 25 .", "The outer surface of hooping layer 25 can be a cylinder of diameter D 7 .", "[0020] The connecting principle consists in using an intermediate part screwed onto the two ends of the hooped tubes with a sealing function and locking means for fastening the three parts together.", "The walls of the three parts have to be such that they meet the mechanical requirements, notably the internal pressure resistance.", "[0021] [0021 ]FIG. 3 shows intermediate connecting part 3 .", "Connecting part 3 is a tube of inside diameter D 4 and of outside diameter D 5 , and it comprises a central collar or shoulder 33 of diameter D 6 .", "Connecting part 3 stretches for example over an axial length of about 330 mm.", "Outside diameter D 5 is substantially equal to or slightly smaller than inside diameter D 1 of the end of tube 1 or 2 in the vicinity of first smooth surface 22 .", "Threads 31 and 32 are machined on the outer surface at both ends of connecting part 3 .", "The outside diameter of part 3 in the vicinity of threads 31 and 32 and the characteristics of threads 31 and 32 are so selected that threads 31 and 32 can respectively cooperate with box threads 23 of tubes 1 and 2 .", "At the centre of connecting part 3 , the outer surface of the tube comprises a shoulder 33 , i.e. a part in the middle of connecting element 3 has an outside diameter D 6 that is larger than diameter D 5 of connecting part 3 .", "The diameter D 6 of shoulder 33 is substantially constant.", "The shoulder can for example stretch over an axial length of about 40 mm.", "At each axial end of shoulder 33 , a wall 38 connects the outer surface of shoulder 33 of diameter D 6 to the tube of diameter D 5 .", "The two walls 38 can be substantially perpendicular to the axis of connecting part 3 .", "On the outer surface of shoulder 33 , grooves 34 are machined parallel to the axis of connecting part 3 .", "Connecting part 3 can for example comprise four grooves 34 evenly distributed on the outer circumference of shoulder 33 .", "At the bottom of each groove 34 , two blind holes 35 are pierced in the radial direction of connecting part 3 .", "Holes 35 are tapped.", "On the outer surface of connecting part 3 , two slots 36 are machined between shoulder 33 and thread 31 , and two slots 37 are machined between shoulder 33 and thread 32 .", "[0022] [0022 ]FIG. 4 shows a locking means in form of a pipe bracket 4 .", "The bracket is U-shaped, i.e. a bracket 4 consists of a base 40 (which forms the bottom of the U) and of two legs, or edge, 41 and 42 (which form the two free branches of the U).", "Base 40 has the shape of a plate of width l, of length L and of thickness e. Legs 41 and 42 form, in a perpendicular direction, the extension of base 40 in the direction of its length.", "Thus, legs 41 and 42 can have a thickness and a width substantially equal to thickness e and width l of base 40 .", "The thickness e of base 40 is pierced with two holes 43 .", "Preferably, width l of bracket 4 is selected substantially equal to the width of grooves 34 of connecting element 3 .", "Thickness e of legs 41 and 42 is preferably selected substantially equal to the width of grooves 21 of tubes 1 and 2 .", "[0023] With reference to FIG. 1, connection of hooped tubes 1 and 2 by means of intermediate connecting part 3 and of brackets 4 is carried out as follows: [0024] a seal means 10 is arranged in each slot 36 of connecting part 3 .", "Seal means 10 can be, for example, doughnut rings made from an elastomer.", "Other types of composite joints can also be used;", "[0025] intermediate connecting part 3 is screwed on in the end of tube 1 .", "Pin thread 31 of connecting element 3 is screwed onto box thread 23 of tube 1 .", "Connecting part 3 can be screwed on in the end of tube 1 until the end of tube 1 rests against a wall 38 of shoulder 33 of connecting element 3 .", "Connecting part 3 being screwed in the end of tube 1 , surface 22 of tube 1 faces slots 36 comprising seal means 10 so that the link between tube 1 and intermediate connecting part 3 is sealed;", "[0026] a seal means 10 is arranged in each slot 37 of intermediate connecting part 3 ;", "[0027] the end of tube 2 is screwed onto connecting part 3 .", "Pin thread 32 of connecting part 3 is screwed onto box thread 23 of tube 2 .", "Tube 2 can be screwed onto connecting element 3 until the end of tube 2 rests against a wall 38 of shoulder 33 of connecting part 3 .", "The end of tube 2 being screwed on connecting part 3 , surface 22 of tube 2 faces slots 37 comprising seal means 10 so that the link between intermediate connecting part 3 and tube 2 is sealed;", "[0028] brackets 4 are placed in grooves 34 .", "Legs 41 and 42 respectively fit into grooves 21 of tubes 1 and 2 .", "Thus, brackets 4 prevent axial displacement of each tube 1 and 2 in relation to intermediate part 3 , and consequently prevent the assembly from unscrewing;", "[0029] screws 11 are inserted into each hole 43 of brackets 4 and each thread 35 of connecting part 3 so as to hold brackets 4 in grooves 34 , and legs 41 and 42 in grooves 21 (in FIG. 1, only one screw 11 is shown).", "[0030] Connection can be performed without applying a makeup torque when screwing tubes 1 and 2 onto connecting element 3 .", "Tubes 1 and 2 resting against connecting element 3 and installing brackets 4 can be sufficient to provide the connection.", "[0031] Preferably, the geometry of tubes 1 , 2 , of intermediate connecting part 3 , of brackets 4 , diameter D 6 of the outer surface of shoulder 33 and thickness e of brackets 4 are so selected that the connection according to the present invention is inscribed in a cylinder of diameter D 7 (diameter D 7 being the outside diameter of hooping layer 25 ).", "Thus, the hooped tubes connected according to the present invention can be used without taking account of the connection.", "In particular, this feature is advantageous for storing pipe elements made of connected hooped tubes because the bearing surfaces are on the hooped lengths and not localized on the connections.", "[0032] In FIG. 5, the inside diameter of connecting zones 57 and 58 at the ends of a pipe element can be smaller than the inside diameter of tubes 51 to 56 .", "Preferably, inside diameter D 4 of connecting part 3 is so selected as to be larger than the smallest inside diameter of the connecting zones.", "[0033] The connecting means are so designed that the mechanical strength of the pipe element is at least equal to the strength of a hooped tube section.", "Furthermore, the resistance to the internal pressure, the working pressure, the test pressure, or the burst pressure of the pipe element made of hooped tube sections is identical or at least equal to the pressure resistance of a hooped tube section.", "It is clear that, for these conditions to be met, the inside diameter of the intermediate part is slightly smaller than the inside diameter of a hooped tube section.", "But the length of the intermediate part is short in relation to the length of a hooped tube section, which does practically not increase the pressure drops during circulation.", "[0034] [0034 ]FIG. 5 shows a pipe element made of hooped tubes 50 according to the invention.", "The element consists of six sections 51 to 56 .", "Sections 51 to 56 are hooped tubes.", "The length of four of the six hooped tubes 51 to 56 is about 4 meters.", "The length of two of the six hooped tubes 51 to 56 is about 2.5 meters.", "The pipe element according to the invention stretches over a length of about 21 meters.", "Hooped tube sections 51 to 56 are connected by means of intermediate connecting parts 3 described above.", "Section 51 at one end of pipe element 50 has a connecting zone 57 which can cooperate with connecting zone 58 of section 56 at the other end of another pipe element 50 ." ]
BACKGROUND OF THE INVENTION The present invention relates to a process for producing a high strength structural member and a starting powder of a light alloy for use in carrying out the process. There is a conventionally known process for producing a structural member which comprises forming a green compact using a supersaturated solid solution powder (having a crystalline phase volume fraction C (Vf) of 100%) of a light alloy as a starting, powder for the purpose of providing an increased strength of the resulting member, and subjecting the green compact to a hot extrusion. However, the above-described starting powder exhibits poor in moldability and in bondability between the particles thereof, resulting in a failure to produce a high strength member at lower working rates. For this reason, a large-sized apparatus must be used in order to provide a higher working rate. The employment of such a means causes a problem in that the production cost of the member is increased because of the increased equipment cost and the durability of the equipment is lower. Another problem is that if the green compact is subjected to a hot extrusion at a higher working rate, the metallographic structure to the resulting member becomes fibrous and it is difficult of provide a homogeneous metallographic structure. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a process of the type described above wherein an increase in strength of the member can be achieved even at a lower working rate by use of a unique starting powder. The present invention provides a high strength structural member and a process for producing that high strength structural member, comprising the steps of preparing a mixed powder as a starting powder of a light alloy, which contains a main powder component and an additional powder component and has a volume fraction P (Vf) of the additional powder component of at least 5%, the main powder component comprising a crystalline phase alloy powder having a crystalline phase volume fraction C (Vf) substantially equal to 100%, the additional powder component comprising at least one of either a mixed phase alloy powder including a crystalline phase and an amorphous phase and having an amorphous phase volume fraction A (Vf) of at least 5% or a single amorphous phase alloy powder having an amorphous phase volume fraction A (Vf) of 100%, and subjecting the starting powder to a forming. The present invention also provides a starting powder of a light alloy for use in production of a high strength structural member, the starting powder being a mixed powder containing a main powder component and an additional powder component and having a volume fraction P (Vf) of the additional powder component of at least 5%, the main powder component comprising a crystalline phase alloy powder having a crystalline phase volume fraction C (Vf) substantially equal to 100%, the additional powder component comprising at least one of either a mixed-phase alloy powder including a crystalline phase and an amorphous phase and having an amorphous phase volume fraction A (Vf) of at least 5% or a single amorphous phase alloy powder having an amorphous phase volume fraction A (Vf) of 100%. In the above producing process, the inclusion of the amorphous phase of a volume fraction A (Vf) of 5% or more in the mixed-phase alloy powder as the additional powder component means that a powder skin layer of the mixed-phase alloy powder is formed of only an amorphous phase due to a powder producing process. The amorphous phase generates the migration of atoms during crystallization, and, therefore, the mixed-phase alloy powder is good in moldability and in bondability between particles thereof even at relatively low working rates. By effectively utilizing such physical properties, it is possible to improve the moldability of the starting powder at a low working rate and to sufficiently bond particles of the main powder component with one another through particles of the mixed-phase alloy powder to provide an increase in strength of the resulting member. The same is true when a single amorphous phase alloy powder is used as the additional powder component. If a starting powder of the above-described type is used, the producing process can be carried out efficiently. It is preferable that the compositions of the alloys for the main and additional powder components be identical or approximate to each other. If the volume fraction P (Vf) of the additional powder component in the starting powder is less than 5%, the resulting member will have a reduced strength and a small elongation, and, therefore, such a volume fraction is not preferred. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in connection with several embodiments and variations thereof, with reference to the accompanying drawings, wherein: FIGS. 1a through 1e are x-ray diffraction patterns of various alloy powders; FIGS. 2a and 2b are thermocurves resulting from the differential thermal analysis of the various alloy powders; and FIGS. 3a through 3d are diagrams illustrating the of a structural member of this invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS For purposes of illustrating the scope of this invention, a molten metal of an aluminum alloy having a composition of Al 92 Fe 5 Y 3 (in which each of the numerical values represents an atom %) was prepared and used to produce mixed-phase alloy powders P 1 to P 4 and a crystalline phase alloy powder P 5 with various diameters by utilizing a conventional high pressure helium (He) gas atomization process. Table I shows metallographic structures and diameters of the alloy powders P 1 to P 5 . TABLE I______________________________________ Volume fraction A Volume Fraction CAlloy Diameter of amorphous phase of CrystallinePowder (μm) (Vf) (%) phase (Vf) (%)______________________________________P.sub.1 <22 50 50P.sub.2 22-26 25 75P.sub.3 26-32 10 90P.sub.4 32-44 5 95P.sub.5 44-63 <1 = 100______________________________________ FIGS. 1a to 1e are X-ray diffraction patterns of the alloy powders P 1 to P 5 , respectively. As is apparent from a comparison of FIGS. 1a to 1e, the number of peaks increases with the increasing percentage of the crystalline phase. FIGS. 2a and 2b are thermocurves resulting from the differential thermal analysis for the alloy powders P 1 to P 5 , wherein FIG. 2a corresponds to the mixed-phase alloy powder P 1 and in FIG. 2b, lines x 1 to x 3 correspond to the mixed-phase alloy powders P 2 to P 4 , respectively, and line x 4 corresponds to the crystalline phase alloy powder P 5 . In each of the alloy powders P 1 to P 5 , the temperature at which the maximum exothermic peak is generated with crystallization is as given in Table II, and, as is apparent from Table II, it can be seen that such temperature is raised with the increasing percentage of the volume fraction C (Vf) of the crystalline phase. TABLE II______________________________________Alloy Powder Temperature (°C.)______________________________________P.sub.1 400.0° C.P.sub.2 406.1° C.P.sub.3 443.7° C.P.sub.4 454.2° C.P.sub.5 471.9° C.______________________________________ Several mixed powders comprising the mixed-phase alloy powders P 1 -P 4 of a predetermined volume fraction P (Vf) (as additional powders) and the crystalline phase powder P 5 (as a main powder) were provided as a starting material. In addition, the crystalline phase alloy powder P 5 was used alone as a starting material for comparison. A green compact of each of these starting powders was subjected to a forming process under heating and pressing conditions to produce structural members. In the present embodiment, the forming process used was a hot extrusion. The procedure used for producing each structural member, as shown in FIGS. 3a-3d, was as follows: i) As shown in FIG. 3a, a starting powder 1 was placed into a cylindrical rubber container 4 comprising a body 2 and a lid 3 and then subjected to a cold isostatic pressing (CIP) under a condition of a pressure of 4,000 kg f/cm 2 . ii) As shown in FIG. 3b, a short columnar green compact 5 having a diameter of 58 mm, a length of 40 mm and a density of 87% was produced by such cold isostatic pressing. iii) As shown in FIG. 3c, the green compact 5 was placed in another cylindrical container 6 made of an aluminum alloy (AA specification 6061 material). The container 6 is comprised of a body 7 having an outside diameter of 78 mm and a length of 70 mm and a lid 8 welded to an opening in the body 7, with the lid 8 having a vent pipe 9 permitting communication between the inside and outside of the body 7. iv) As shown in FIG. 3d, the green compact 5 was placed together with the container 6 into the bore of the body 11 of a single action type hot extruder 10, with the vent pipe 9 extending into a die packer 14 through a die bore 13 in a die 12. In the hot extruder 10, the maximum pressing force was set at 500 tons; the inside diameter of the bore in body 11 was equal to 80 mm and the preheating temperature of the extruder body 11 was 400° C. Then, a vacuum pump 15 was connected to the vent pipe 9 through a rubber pipe 16 to depressurize the inside of the container 6. At the point in time when the degree of vacuum exceeded 10 -5 Torr, a stem 17 was advanced to apply a load of about 120 tons to the container 6 through a dummy block 18. This caused the container 6 to be deformed into close contact with the bore in extruder body 11, so that the temperature of the green compact 5 was rapidly raised and reached 400° C. in about 7 minutes. The gas contained in the green compact 5 was expelled therefrom by the heating and depressurizing action, with the result that the degree of vacuum in the container 6 was reduced, but returned to a condition of a degree of vacuum exceeding 10 -5 Torr after a lapse of about 10 minutes after the temperature of the green compact 5 reached 400° C. The retention time at this temperature depends upon the density, composition, structure and the like of the green compact 5 and may be set in a range of from one minute to two hours. In this example of production, when the degree of vacuum in the container 6 returned to 10 -5 Torr, the green compact 5 was extruded together with the container 6, so that powder particles were bonded with one another, thereby providing a round bar-like structural member. Table III shows the producing conditions for the structural members I to IX and the physical properties thereof. P 1 to P 4 are the mixed-phase alloy powders, and P 5 is the crystalline phase alloy powder. The numerical values added to the alloy powders P 1 to P 5 represent volume fractions (Vf) of alloy powders P 1 to P 5 in the starting powder, respectively. TABLE III______________________________________Producing Conditions E. Pre. Structural MemberS.M. Starting Powder D.B.D. (kg Ten. Stre. Elon.No. P (Vf), (%) (mm) f/mm.sup.2) (kg f/mm.sup.2) (%)______________________________________I 100% P 25 83 48.5 0II 80% P.sub.5 + 20% P.sub.1 25 70 85.2 8.9III 80% P.sub.5 + 20% P.sub.2 25 68 84.9 7.8IV 80% P.sub.5 + 20% P.sub.3 25 72 84.3 8.6V 80% P.sub.5 + 20% P.sub.4 25 67 85.5 9.0VI 90% P.sub.5 + 10% P.sub.4 25 70 84.9 8.3VII 95% P.sub.5 + 5% P.sub.4 25 73 74.0 5.2VIII 97% P.sub.5 + 3% P.sub.4 25 81 56.1 0.6IX 100% P.sub.5 20 98 83.0 9.7______________________________________ The abbreviations used in Table III and their meanings are as follows: S.M. No.=Structural member No. D.B.D.=Die bore diameter E.Pre.=Extruding pressure Ten. Stre.=Tensile strength Elon.=Elongation In Table III, the structural members II to VII are those produced according to the present invention. It can be seen from Table III that any of the members II to VII have a higher strength and a larger elongation than members I or VIII. Severe conditions, such as cooling rate, are imposed in order to produce an alloy powder containing an amorphous phase and therefore, such alloy powder is higher in cost. In the present invention, however, such an alloy powder may be used in a relatively small amount, leading to an increased economy. It is believed that the reason the structural members II to VII have excellent physical properties as described above is as follows. The inclusion of an amorphous phase of a volume fraction A (Vf) of 5% or more in each of the mixed-phase alloy powders P 1 to P 4 means that a skin layer of each of the alloy powders P 1 to P 4 is formed of only an amorphous phase due to the producing process thereof. Such amorphous phase generates the migration of atoms with crystallization, and, hence, the mixed-phase alloy powders P 1 to P 4 are good in moldability and bondability at a powder interface even with a relatively low extrusion ratio (about 9.7). By effectively utilizing such physical properties, it is possible to improve the moldability of the starting powder, even with a lower extrusion ratio. It is also possible to sufficiently bond particles of the crystalline phase alloy powder P 5 with one another through particles of the mixed-phase alloy powders P 1 to P 4 to provide an increase in strength of each of the members II to VII. The same is true when a single amorphous phase alloy powder having an amorphous phase volume fraction A (Vf) of 100% is used as the additional powder, although this is not set forth as an example in Table III. With the structural members I and VIII, a larger extruding pressure is required than with the members II to VII and in addition, the strength thereof is lower and the elongation thereof is small, due to the volume fractions of the mixed-phase alloy powder P 4 being less than 5%. To produce a member having physical properties equivalent to those of the above-described members II to VII by use of only the crystalline phase alloy powder P 5 , it is necessary to reduce the die bore diameter to increase the extrusion ratio to about 15, and a larger extruding pressure is required. Structural member IX of Table III is an example of such a process for comparison with the embodiments of the present invention. In addition to Al 92 Fe 5 Y 3 that was used in the foregoing examples, the compositions of the starting powders which may be used in the present invention include Al 858 Ni 5 Y 10 , Al 84 Ni 10 Ce 6 , Al 84 Ni 10 Dy 6 , Al 85 Ni 5 Y 8 Co 2 , Al 85 Fe 7 .5 Y 7 .5, Al 80 Ni 10 Ca 10 , Mg 82 Ni 8 Y 10 , Mg 76 Ni 10 Ce 10 Cr 4 , Al 83 Ni 5 Y 10 B 2 , Al 83 Ni 5 Y 10 Nb 2 , Al 88 Ni 6 Ca 6 , Al 90 Ni 7 Y 3 , Al 91 Fe 6 Y 3 , Mg 85 Ni 8 Ce 7 , Mg 86 Ni 6 Y 8 and the like (each of the numerical values representing an atom %). According to the present invention, it is possible to produce a high strength structural member even at a lower than normal working rate by using a starting powder as described above and a procedure including subjecting such starting powder to a forming process.
A high strength structural member formed in a forming process using a starting powder of a light alloy. The starting powder is a mixture of a crystalline phase main powder component and at least 5% by volume of an additional powder component which includes between 5% and 100% by volume of an amorphous phase of the light alloy powder and the balance of a crystalline phase.
Briefly describe the main invention outlined in the provided context.
[ "BACKGROUND OF THE INVENTION The present invention relates to a process for producing a high strength structural member and a starting powder of a light alloy for use in carrying out the process.", "There is a conventionally known process for producing a structural member which comprises forming a green compact using a supersaturated solid solution powder (having a crystalline phase volume fraction C (Vf) of 100%) of a light alloy as a starting, powder for the purpose of providing an increased strength of the resulting member, and subjecting the green compact to a hot extrusion.", "However, the above-described starting powder exhibits poor in moldability and in bondability between the particles thereof, resulting in a failure to produce a high strength member at lower working rates.", "For this reason, a large-sized apparatus must be used in order to provide a higher working rate.", "The employment of such a means causes a problem in that the production cost of the member is increased because of the increased equipment cost and the durability of the equipment is lower.", "Another problem is that if the green compact is subjected to a hot extrusion at a higher working rate, the metallographic structure to the resulting member becomes fibrous and it is difficult of provide a homogeneous metallographic structure.", "SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a process of the type described above wherein an increase in strength of the member can be achieved even at a lower working rate by use of a unique starting powder.", "The present invention provides a high strength structural member and a process for producing that high strength structural member, comprising the steps of preparing a mixed powder as a starting powder of a light alloy, which contains a main powder component and an additional powder component and has a volume fraction P (Vf) of the additional powder component of at least 5%, the main powder component comprising a crystalline phase alloy powder having a crystalline phase volume fraction C (Vf) substantially equal to 100%, the additional powder component comprising at least one of either a mixed phase alloy powder including a crystalline phase and an amorphous phase and having an amorphous phase volume fraction A (Vf) of at least 5% or a single amorphous phase alloy powder having an amorphous phase volume fraction A (Vf) of 100%, and subjecting the starting powder to a forming.", "The present invention also provides a starting powder of a light alloy for use in production of a high strength structural member, the starting powder being a mixed powder containing a main powder component and an additional powder component and having a volume fraction P (Vf) of the additional powder component of at least 5%, the main powder component comprising a crystalline phase alloy powder having a crystalline phase volume fraction C (Vf) substantially equal to 100%, the additional powder component comprising at least one of either a mixed-phase alloy powder including a crystalline phase and an amorphous phase and having an amorphous phase volume fraction A (Vf) of at least 5% or a single amorphous phase alloy powder having an amorphous phase volume fraction A (Vf) of 100%.", "In the above producing process, the inclusion of the amorphous phase of a volume fraction A (Vf) of 5% or more in the mixed-phase alloy powder as the additional powder component means that a powder skin layer of the mixed-phase alloy powder is formed of only an amorphous phase due to a powder producing process.", "The amorphous phase generates the migration of atoms during crystallization, and, therefore, the mixed-phase alloy powder is good in moldability and in bondability between particles thereof even at relatively low working rates.", "By effectively utilizing such physical properties, it is possible to improve the moldability of the starting powder at a low working rate and to sufficiently bond particles of the main powder component with one another through particles of the mixed-phase alloy powder to provide an increase in strength of the resulting member.", "The same is true when a single amorphous phase alloy powder is used as the additional powder component.", "If a starting powder of the above-described type is used, the producing process can be carried out efficiently.", "It is preferable that the compositions of the alloys for the main and additional powder components be identical or approximate to each other.", "If the volume fraction P (Vf) of the additional powder component in the starting powder is less than 5%, the resulting member will have a reduced strength and a small elongation, and, therefore, such a volume fraction is not preferred.", "BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in connection with several embodiments and variations thereof, with reference to the accompanying drawings, wherein: FIGS. 1a through 1e are x-ray diffraction patterns of various alloy powders;", "FIGS. 2a and 2b are thermocurves resulting from the differential thermal analysis of the various alloy powders;", "and FIGS. 3a through 3d are diagrams illustrating the of a structural member of this invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS For purposes of illustrating the scope of this invention, a molten metal of an aluminum alloy having a composition of Al 92 Fe 5 Y 3 (in which each of the numerical values represents an atom %) was prepared and used to produce mixed-phase alloy powders P 1 to P 4 and a crystalline phase alloy powder P 5 with various diameters by utilizing a conventional high pressure helium (He) gas atomization process.", "Table I shows metallographic structures and diameters of the alloy powders P 1 to P 5 .", "TABLE I______________________________________ Volume fraction A Volume Fraction CAlloy Diameter of amorphous phase of CrystallinePowder (μm) (Vf) (%) phase (Vf) (%)______________________________________P.", "sub[.", "].1 <22 50 50P.", "sub[.", "].2 22-26 25 75P.", "sub[.", "].3 26-32 10 90P.", "sub[.", "].4 32-44 5 95P.", "sub[.", "].5 44-63 <1 = 100______________________________________ FIGS. 1a to 1e are X-ray diffraction patterns of the alloy powders P 1 to P 5 , respectively.", "As is apparent from a comparison of FIGS. 1a to 1e, the number of peaks increases with the increasing percentage of the crystalline phase.", "FIGS. 2a and 2b are thermocurves resulting from the differential thermal analysis for the alloy powders P 1 to P 5 , wherein FIG. 2a corresponds to the mixed-phase alloy powder P 1 and in FIG. 2b, lines x 1 to x 3 correspond to the mixed-phase alloy powders P 2 to P 4 , respectively, and line x 4 corresponds to the crystalline phase alloy powder P 5 .", "In each of the alloy powders P 1 to P 5 , the temperature at which the maximum exothermic peak is generated with crystallization is as given in Table II, and, as is apparent from Table II, it can be seen that such temperature is raised with the increasing percentage of the volume fraction C (Vf) of the crystalline phase.", "TABLE II______________________________________Alloy Powder Temperature (°C.)______________________________________P.", "sub[.", "].1 400.0° C.P.sub[.", "].2 406.1° C.P.sub[.", "].3 443.7° C.P.sub[.", "].4 454.2° C.P.sub[.", "].5 471.9° C.______________________________________ Several mixed powders comprising the mixed-phase alloy powders P 1 -P 4 of a predetermined volume fraction P (Vf) (as additional powders) and the crystalline phase powder P 5 (as a main powder) were provided as a starting material.", "In addition, the crystalline phase alloy powder P 5 was used alone as a starting material for comparison.", "A green compact of each of these starting powders was subjected to a forming process under heating and pressing conditions to produce structural members.", "In the present embodiment, the forming process used was a hot extrusion.", "The procedure used for producing each structural member, as shown in FIGS. 3a-3d, was as follows: i) As shown in FIG. 3a, a starting powder 1 was placed into a cylindrical rubber container 4 comprising a body 2 and a lid 3 and then subjected to a cold isostatic pressing (CIP) under a condition of a pressure of 4,000 kg f/cm 2 .", "ii) As shown in FIG. 3b, a short columnar green compact 5 having a diameter of 58 mm, a length of 40 mm and a density of 87% was produced by such cold isostatic pressing.", "iii) As shown in FIG. 3c, the green compact 5 was placed in another cylindrical container 6 made of an aluminum alloy (AA specification 6061 material).", "The container 6 is comprised of a body 7 having an outside diameter of 78 mm and a length of 70 mm and a lid 8 welded to an opening in the body 7, with the lid 8 having a vent pipe 9 permitting communication between the inside and outside of the body 7.", "iv) As shown in FIG. 3d, the green compact 5 was placed together with the container 6 into the bore of the body 11 of a single action type hot extruder 10, with the vent pipe 9 extending into a die packer 14 through a die bore 13 in a die 12.", "In the hot extruder 10, the maximum pressing force was set at 500 tons;", "the inside diameter of the bore in body 11 was equal to 80 mm and the preheating temperature of the extruder body 11 was 400° C. Then, a vacuum pump 15 was connected to the vent pipe 9 through a rubber pipe 16 to depressurize the inside of the container 6.", "At the point in time when the degree of vacuum exceeded 10 -5 Torr, a stem 17 was advanced to apply a load of about 120 tons to the container 6 through a dummy block 18.", "This caused the container 6 to be deformed into close contact with the bore in extruder body 11, so that the temperature of the green compact 5 was rapidly raised and reached 400° C. in about 7 minutes.", "The gas contained in the green compact 5 was expelled therefrom by the heating and depressurizing action, with the result that the degree of vacuum in the container 6 was reduced, but returned to a condition of a degree of vacuum exceeding 10 -5 Torr after a lapse of about 10 minutes after the temperature of the green compact 5 reached 400° C. The retention time at this temperature depends upon the density, composition, structure and the like of the green compact 5 and may be set in a range of from one minute to two hours.", "In this example of production, when the degree of vacuum in the container 6 returned to 10 -5 Torr, the green compact 5 was extruded together with the container 6, so that powder particles were bonded with one another, thereby providing a round bar-like structural member.", "Table III shows the producing conditions for the structural members I to IX and the physical properties thereof.", "P 1 to P 4 are the mixed-phase alloy powders, and P 5 is the crystalline phase alloy powder.", "The numerical values added to the alloy powders P 1 to P 5 represent volume fractions (Vf) of alloy powders P 1 to P 5 in the starting powder, respectively.", "TABLE III______________________________________Producing Conditions E. Pre.", "Structural MemberS.M. Starting Powder D.B.D. (kg Ten.", "Stre.", "Elon.", "No.", "P (Vf), (%) (mm) f/mm.", "sup[.", "].2) (kg f/mm.", "sup[.", "].2) (%)______________________________________I 100% P 25 83 48.5 0II 80% P.sub[.", "].5 + 20% P.sub[.", "].1 25 70 85.2 8.9III 80% P.sub[.", "].5 + 20% P.sub[.", "].2 25 68 84.9 7.8IV 80% P.sub[.", "].5 + 20% P.sub[.", "].3 25 72 84.3 8.6V 80% P.sub[.", "].5 + 20% P.sub[.", "].4 25 67 85.5 9.0VI 90% P.sub[.", "].5 + 10% P.sub[.", "].4 25 70 84.9 8.3VII 95% P.sub[.", "].5 + 5% P.sub[.", "].4 25 73 74.0 5.2VIII 97% P.sub[.", "].5 + 3% P.sub[.", "].4 25 81 56.1 0.6IX 100% P.sub[.", "].5 20 98 83.0 9.7______________________________________ The abbreviations used in Table III and their meanings are as follows: S.M. No.=Structural member No. D.B.D.=Die bore diameter E.Pre.", "=Extruding pressure Ten.", "Stre.", "=Tensile strength Elon.", "=Elongation In Table III, the structural members II to VII are those produced according to the present invention.", "It can be seen from Table III that any of the members II to VII have a higher strength and a larger elongation than members I or VIII.", "Severe conditions, such as cooling rate, are imposed in order to produce an alloy powder containing an amorphous phase and therefore, such alloy powder is higher in cost.", "In the present invention, however, such an alloy powder may be used in a relatively small amount, leading to an increased economy.", "It is believed that the reason the structural members II to VII have excellent physical properties as described above is as follows.", "The inclusion of an amorphous phase of a volume fraction A (Vf) of 5% or more in each of the mixed-phase alloy powders P 1 to P 4 means that a skin layer of each of the alloy powders P 1 to P 4 is formed of only an amorphous phase due to the producing process thereof.", "Such amorphous phase generates the migration of atoms with crystallization, and, hence, the mixed-phase alloy powders P 1 to P 4 are good in moldability and bondability at a powder interface even with a relatively low extrusion ratio (about 9.7).", "By effectively utilizing such physical properties, it is possible to improve the moldability of the starting powder, even with a lower extrusion ratio.", "It is also possible to sufficiently bond particles of the crystalline phase alloy powder P 5 with one another through particles of the mixed-phase alloy powders P 1 to P 4 to provide an increase in strength of each of the members II to VII.", "The same is true when a single amorphous phase alloy powder having an amorphous phase volume fraction A (Vf) of 100% is used as the additional powder, although this is not set forth as an example in Table III.", "With the structural members I and VIII, a larger extruding pressure is required than with the members II to VII and in addition, the strength thereof is lower and the elongation thereof is small, due to the volume fractions of the mixed-phase alloy powder P 4 being less than 5%.", "To produce a member having physical properties equivalent to those of the above-described members II to VII by use of only the crystalline phase alloy powder P 5 , it is necessary to reduce the die bore diameter to increase the extrusion ratio to about 15, and a larger extruding pressure is required.", "Structural member IX of Table III is an example of such a process for comparison with the embodiments of the present invention.", "In addition to Al 92 Fe 5 Y 3 that was used in the foregoing examples, the compositions of the starting powders which may be used in the present invention include Al 858 Ni 5 Y 10 , Al 84 Ni 10 Ce 6 , Al 84 Ni 10 Dy 6 , Al 85 Ni 5 Y 8 Co 2 , Al 85 Fe 7 [.", "].5 Y 7 [.", "].5, Al 80 Ni 10 Ca 10 , Mg 82 Ni 8 Y 10 , Mg 76 Ni 10 Ce 10 Cr 4 , Al 83 Ni 5 Y 10 B 2 , Al 83 Ni 5 Y 10 Nb 2 , Al 88 Ni 6 Ca 6 , Al 90 Ni 7 Y 3 , Al 91 Fe 6 Y 3 , Mg 85 Ni 8 Ce 7 , Mg 86 Ni 6 Y 8 and the like (each of the numerical values representing an atom %).", "According to the present invention, it is possible to produce a high strength structural member even at a lower than normal working rate by using a starting powder as described above and a procedure including subjecting such starting powder to a forming process." ]
This is a continuation of Ser. No. 504,651, filed June 15, 1983. FIELD OF THE INVENTION The invention is in the field of ceramic coatings on substrates. The substrates may be metal or nonmetal, homogenous or composite materials. The invention has particular application for protective coatings for turbine engine components. Significant improvements in durability and high temperature capability of combustion zone parts are possible. BACKGROUND ART U.S. Pat. No. 4,321,311 to Strangman describes a composite coating system for thermal barrier ceramic coatings on metal parts. The system has three interrelated elements. (1) a metallic layer of an alumina forming metal, such as MCrAlY alloy where M is Ni, Co, NiCo, Fe or other metals, (2) a continuous adherent alumina layer formed on the metallic layer, and (3) a discontinuous ceramic layer having a particular columnar morphology on the alumina layer. The ceramic layer has columnar grains, oriented substantially perpendicular to the surface of the substrate and having free surfaces extending down to the alumina layer. The voids between the individual ceramic columns enlarge and diminish to accommodate strains arising because of the differential thermal expansion between the metallic and ceramic materials. This patent teaches deposition cf the columnar ceramic coating by positioning the substrate over an electron-beam heated pool of molten ceramic in vacuum. The substrate temperature was maintained in the range 1000° to 1500° F. to provide a relatively coarse columnar structure. In order to assure that the ceramic coating contained the stoichiometric amount of oxygen, the dark, as-deposited ceramic was heat treated at about 1600° F. for 32 hours in an oxygen containing atmosphere so that the color lightened to a shade typical of the stoichiometric ceramic. A closely related U.S. Pat. No. 4,321,310 to Ulion and Ruckle, teaches polishing of the interface between the metallic layer and the alumina layer to provide a surface roughness of less than about 25 microinches RMS average. This increases the adherence of the columnar ceramic layer and, thus, increases the cyclic temperature durability of the coating system. The prior art also teaches the deposition of ceramic materials, such as yttria, by electron-beam heated evaporation of a metal or alloy vapor in the presence of oxygen. See, for example, R. F. Bunshah, "Structure/property relationships in evaporated thick films and bulk coatings", J. Vac. Sci. Technol. Vol. 11, p. 633-39, July/Aug 1974. SUMMARY OF THE INVENTION In the present invention, a layer of dense substoichiometric ceramic material is deposited on a substrate. The coating may be an oxide, nitride, carbide, boride, silicide or other refractory ceramic material. A ceramic starting material is refined and probably chemically reduced by heating with an electron beam in vacuum. This material becomes substoichiometric because of the evolvement of oxygen, nitrogen or other reactive gas. The refined, substoichiometric material is then evaporated in vacuum and deposited on a heated substrate to form a dense, substoichiometric ceramic layer. The object to be coated may be a metal or non-metal, but for proper adherence it must have a stable ceramic surface which is chemically and mechanically compatible with the ceramic coating to be applied. In the case of a metal object, the object may be covered with ceramic-forming metal layer which is then converted to a ceramic layer by heating the object in an atmosphere containing the appropriate reactive gas. In particular, for a superalloy turbine part, the object may be coated with an alumina forming layer and heated in a residual air atmosphere. If desired, an overcoating of columnar, substantially stoichiometric ceramic material can be formed by reactively depositing a ceramic vapor in the presence of oxygen or other reactive gas component of the ceramic. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional line drawing illustrating a coating system according to the invention. FIG. 2 is a scanning electron microscope photomicrograph (approximately 5000×magnification) showing a cross section of a sample of an experimental coating system according to the invention. FIG. 3 is a composite of four transverse electron microscope photomicrographs showing a cross section of a sample of an experimental coating system. The scale is indicated in the figure. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a coating system for a metal part according to the invention. The base material 1 is coated with an alumina forming metallic layer 2 on which an alumina containing oxide layer 3 is formed. The layer of dense ceramic material 4 is formed on the oxide layer 3, and the columnar, substantially stoichiometric ceramic material 5 is formed on the dense ceramic layer. The density of the material of layer 4 is preferably greater than 94%, typically 96%, of the maximum theoretical density of the ceramic material. Open porosity typically disappears at about 94% theoretical density. The latter is about 6 g/cm 3 for zirconia stablilized with 20 weight percent yttria (ZrO 2 with 20% Y 2 O 3 ). The density of the columnar ceramic material 5 is typically 50 to 90% of the theoretical maximum value. FIG. 2 is a scanning electron microscope photomicrograph showing a polished cross-sectional sample of a coating system of the type illustrated in FIG. 1. The base material is a superalloy which was polished to surface roughness 40 to 50 micrometers (15 to 20 microinches) RMS and coated with a layer 12 of NiCrAlY on which an alumina containing oxide layer 13 was formed. The nominal NiCrAlY composition was Ni (remainder), 22% Cr, 12% Al, and 0.3% Y. The dense ceramic material 14 and the columnar ceramic material 15 are both ZrO 2 with 20% Y 2 O 3 . Note that the layer of dense ceramic material 14 bridges over the surface defect 19 caused by a spit of ZrO 2 or Y 2 O 3 from the coating source. A preferred process for depositing a ceramic coating on a metallic substrate will now be described. Typically, the base article is composed of a metal alloy, such as stainless steel 302, or Inconel 718, or a superalloy, such as Ni or Co base, Cr containing alloys, known as Waspalloy, MAR-M-247 or PWA 1455. The surface is polished, preferably to a surface roughness of 10 to 250 nm(0.5 to 10 microinches) RMS average. The polishing may be accomplished by mechanical grinding and polishing, perhaps in conjunction with abrasive slurry or electrochemical polishing techniques. The polished surface is cleaned by appropriate processes, such as vapor honing and ultrasonic techniques. The polished article is coated with a metallic layer of an alumina (Al 2 O 3 ) forming material, such as Al, Ni 3 Al or MCrAlY, by an appropriate process. This may be done by physical vapor deposition, low pressure plasma spray, sputtering, or pack diffusion. This metallic coating typically has a thickness of 0.12 mm (0.005 inches), but thicknesses in the range from 0.5 micrometers to 10 mm (2×10 -5 to 0.5 inches) may be appropriate depending upon the application. In addition, intermediate layers between the alumina forming metal coating and the metal base may be used. The coated base is glass bead peened in a conventional manner, preferably with new glass beads at a pressure of 0.3 to 0.4 MPa (50 to 60 pounds per square inch). The part is then thoroughly cleaned ultrasonically and degreased, preferably in a flurocarbon liquid which does not contain a drying agent. The part is mounted on an appropriate fixture and introduced into a first chamber or load lock of a vacuum coating system. The load lock is evacuated to a suitable pressure, such as less than 10 -3 torr. Radiant or electron beam heaters preheat the article and maintain its temperature at a value between 870° and 1100° C. (1600° and 2000° F.) for a time between 10 and 30 minutes so as to dry, degas, and evaporatively clean the surface. During this time, the alumina forming material is oxidized to form a layer of mixed metal oxides having a typical thickness of 0.5 to 2 micrometers. Of course, if the alumina forming material 12 is simply Al, the alumina containing layer 13 is just alumina and not mixed metal oxides. FIG. 3 illustrates the possible complexity of the alumina containing oxide layer 13 of the sample of FIG. 2. It is believed that when oxidation begins, a porous layer of mixed metal oxides forms on the surface 17 of the layer 12 of the alumina forming metal coating. The various metal components of the mixed oxides are in approximately the same relative quantities as in the metal layer 12. As oxidation continues, aluminum oxide grains form and grow until they form a continuous, dense alumina layer 13a having a thickness of 0.25 to 0.5 micrometers. The continuous alumina layer forms an oxygen barrier and stops further oxidation. The dense alumina and the porous metal oxide layers have a definite interface 16. The dense zirconia layer 14 is deposited directly on the surface 18 of the remaining porous layer 13b of mixed metal oxides. The ceramic material to be vaporized is heated by an electron beam in a chamber which is constantly pumped to evacuate it. The material is melted in a crucible and brought to a temperature where it is refined and probably chemically reduced. The appropriate temperature range depends upon the material and is not known precisely. For ZrO 2 stabilized with 20 weight percent Y 2 O 3 , the preferred temperature is believed between 1800° and 2000° C. (3270° and 3630° F.). A suitable operating temperature is obtained by setting the electron beam power just below that which produces rapid evaporation. A radiant heater is used to heat the walls and outgas the chamber. The refining and reducing step is continued for several minutes until a quantity of substoichiometric ceramic material is produced near the heated surface. This may be indicated by a reduction in the system pressure to a low value, such as 5×10 -5 torr, as the quantity of oxygen or other reactive gas evolved from the material declines. The substoichiometric ceramic liquid is black and glassy and has a high density, believed greater than about 96% of the theoretical maximum for the ceramic material. Enough of the dense substoichiometric material must be available to provide a dense layer of the desired thickness on the substrate. A vapor shield or shutter covers the crucible until coating actually begins. The part to be coated is transferred into the evacuated chamber and positioned over the covered crucible at an appropriate distance. The substrate is rotated at a rate, preferably greater than 10 revolutions per minute (rpm). The substrate temperature is maintained at a value between 900° and 1200° C. (1650° and 2200° F.) by a radiant or other heater. The chamber pressure is preferably 10 -4 torr or less. A pressure of less than 2×10 -5 torr is even more preferred. When all is ready, the electron beam power is increased to a value which provides rapid evaporation. A coating deposition rate of between 10 nm/min. and 25 micrometers/min. is preferred. A rate of 500 nm/min. or less is preferred for maximum density. When coating is to begin, the crucible is uncovered and the part is exposed to the substoichiometric vapor for a length of time suitable to provide a layer of dense ceramic coating having the desired thickness. This thickness must be sufficient to provide a continuous covering of the substrate surface, but less than the thickness which would yield a residual stress of formation greater than the strength of the ceramic coating or the strength of the ceramic coating-substrate interface. At minimum radius of curvature, the thickness of the dense ceramic coating is preferably less than about 10 times the minimum radius of curvature. Minimum radii of curvatures of 12 micrometers to 1.2 mm (0.0005 to 0.05 inches) are frequently used in turbine engine components. For maximum thermal cycle durability the thickness is preferably 2 to 10 times greater than the RMS average surface roughness of the substrate. Useful coating thicknesses of between 1 nm and 10 mm appear possible. After the dense substoichiometric layer is formed, oxygen is introduced into the coating chamber to maintain a suitable pressure, preferably between 0.5 and 2 millitorr, but pressures in the range 0.1 to 10 millitorr may be useful at times. Tubes and nozzles are used to direct the oxygen gas to impinge upon the substrate. Use of an automatic flow valve is preferred in order to maintain precise control. The pressure of all other gases is preferably less than 10% of the total pressure. Introduction of oxygen gas increases the oxygen content of the dense ceramic layer and initiates formation of a columnar, substantially stoichiometric ceramic. The oxygen flow rate is proportional to the rate of deposition. The substrate temperature is preferably maintained at a constant value in the range of 540° to 1200° C. (1000° to 2200° F.). The electron beam power and substrate rotation rates are comparable to those for depositing the dense ceramic layer. When the desired thickness of columnar ceramic has been obtained, the vapor source is covered, the electron beam power is reduced, the oxygen flow is halted, and the substrate heater turned off. The coated article is withdrawn into the load lock and cooled to approximately 150° C. (300° F.) before it is removed from the vacuum system. Increased adhesion can be obtained by annealing the coated part from 10 minutes to several hours in an air furnace at a temperature 55° to 280° C. (100° to 500° F.) above the temperature maintained during formation of the columnar ceramic. The density of the ceramic layers increases with the substrate temperature during deposition and decreases as the deposition rate increases. It has been observed that the ratio of coating density to theoretical maximum density increases almost linearly as the substrate rotation rate increases from 10 to 50 rpm. Reciprocal and other types of substrate motion are possible. An average substrate speed of greater than 76 cm/min. (30 inches per minute) is preferred for uniformity and maximum density. The specific electron beam powers necessary for refining and deposition depends upon many factors but are easily determined by experiment. For ZrO 2 in a circular cruciable 10 cm (4 inches) in diameter where the onset of rapid evaporation is typically about 12 kW, refining is done at about 10 kW and deposition at about 20 kW. Dense ceramic layers deposited according to the invention have an extremely fine grain size. As is indicated in FIG. 3, the grains have an initial average width perpendicular to the growth direction of less than about 100 nm. Such small grain sizes are preferred for maximum adherence to the substrate. In known prior ceramic layers, the initial average width is typically 500 nm or more. EXAMPLE 1 A ceramic coating was applied to a first-stage turbine blade for a gas turbine engine. The superalloy blade was approximately 10×4×4 cm (4×1.5×1.5 inches) in size and had an airfoil region to be coated having a radii of curvature ranging down to about 25 micrometers (0.001 inches). The part was cleaned by a vapor honing process and coated with a layer of CoCrAlY by a conventional electron-beam heated evaporation process similar to that described in U.S Pat. No. 3,798,055. The CoCrAlY coating had a nominal thickness of 0.12 mm (0.005 inches) and a nominal composition of Co (remainder), 21% Cr, 12% Al, and 0.3% Y. After application of the CoCrAlY coating, the part was glass bead peened and then heat treated in a dry hydrogen atmosphere at a temperature of 980° C. (1800° F.). After these preliminary steps, the part had an average surface roughness of approximately 0.001 mm (60 microinches) RMS average on the curved surfaces which were to be coated. The part was fixtured on a rotatable shaft and introduced into a load lock which was then evacuated to a pressure of approximately 2×10 -4 torr. The part was introduced into a vacuum furnace chamber and rotated at 12 rpm while it was heated by a radiant heater to a temperature of about 980° C. (1800° F.) for about 10 minutes to form a 1 to 2 micrometer thick layer of alumina containing metal oxide on the surface. During this time, a compressed ingot of white, porous pellets of ZrO 2 stabilized by 20 weight percent Y 2 O 3 was melted and refined in an electron beam in a circular crucible having a diameter of 10 cm (4 inches) positioned about 20 cm (8 inches) below the part. The pressure in the furnace chamber was about 2×10 -4 torr and a radiant heater over the crucible heated a witness substrate to about 980° C. (1800° F.). The electron beam power was just below that for the onset of rapid evaporation. To begin coating, the electron beam power was increased to about 30 kW and the crucible uncovered to expose the rotating part to the vapor. The part was coated for approximately 90 seconds to deposit a dense, substoichiometric ceramic layer having an estimated thickness of approximately 45 micrometers. After 90 seconds, oxygen was introduced into the chamber to provide a partial pressure of between 0.5 and 1 millitorr. The part continued to rotate at approximately 12 rpm for approximately 30 minutes so as to deposit a columnar ceramic layer having a thickness of approximately 0.1 mm (0.005 inches). The finished part was returned to the load lock and cooled before being removed from the vacuum system. This part was tested for cyclic heating and cooling by moving it into and out of an air furnace maintained at about 1000° C. (1830° F.) with a cycle time of 10 minutes. The part survived approximately 500 cycles with no spauling or delamination before failure occurred. Other parts were coated by a similar process except that the duration of the time of the exposure of the part to the substoichiometric vapor before the introduction of oxygen into the chamber was varied from about 3 to 90 seconds. The results of thermal cycle testing of these parts is shown in Table I. TABLE I______________________________________ Substoichiometric Thermal CyclesRun # Coating Time to Failure______________________________________157,166 3 sec. 0160 19 161*161 19 2016159 43 500165 60 432 -158 90 500164 Entire 1______________________________________ *Equipment failure The thickness of the dense layer is determined by the length of time of exposure to the substoichiometric ceramic vapor before introduction of the reactive gas. From the data of Table I, it is clear that the optimum time was approximately 19 seconds under the conditions prevailing. This corresponded to a thickness of approximately 10 micrometers for the dense, substoichiometric layer. EXAMPLE 2 A part similar to those of Example 1 was coated by a process similar to that of Example 1 except that it was not heat treated in dry hydrogen. The coating interval before oxygen gas was introduced was 19 seconds, the approximate optimum value determine from Table 1. This part survived 4000 cycles of the thermal test. Non-metallic substrates may also be coated. The substrate may be elemental, such as carbon graphite; single crystalline ceramic, such as sapphire or silicon nitride; polycrystalline ceramic, such as quartz or alumina; or an amorphous material, such as glassy SiO 2 or boro-alumina silicates. Dense ceramic coatings of Al 2 O 3 , SiN and SiO 2 have been applied to ceramic substrates. The surface of a ceramic substrate is preferably polished to a surface finish that is limited by the homogeniety of the substrate material. This can be done by the processes mentioned in the case of metallic substrates or by fire polishing in an inert or reactive media, or by reactive ion etching. Depending upon the polishing scheme, drying and ultrasonic cleaning may be preferred to remove polishing media or chemical residue. The substrate is mounted on an appropriate fixture, and introduced into a load lock, and heated, by radiant and or electron beam means, for a time between 10 and 30 minutes, preferably to a temperature just below its weakening or melting point. Substrate outgassing may require a longer time. During this time, reactive ion etching or sputtering from the sample may be performed, if required to complete surface preparation. Selective gas reactions or electron beam impingement may also be used to modify the chemical and structural makeup of the substrate surface. Preparation of a special alumina containing layer is generally unnecessary for a non-metallic substrate. The preferred procedure for depositing the dense, layer is also similar to that described for metallic substrates. For ceramic substrates, the substrate adhesion, density and strength of the dense ceramic coating layer can be improved by depositing at a formation temperature just below the melting point of the substrate or coating, whichever is lower. If desired, the dense ceramic coating can be made substantially stoichiometric or a columnar ceramic overcoat can be made by introducing the appropriate reactive gas following deposition of the dense layer. The thickness of the dense ceramic layer can be substantially greater on a ceramic substrate than on a metallic substrate because the difference in thermal expansion coefficients of coating and substrate will normally be much less. Hence, dense erosion and abrasion resistant ceramic coatings having thickness of 10 to 100 micrometers can be manufactured which have thermal cycle durability equivalent to much thinner coatings on metallic substrates; thinner by the ratio of the thermal expansion coefficient of the ceramic substrate to that of the metallic substrate. Alternatively, thin dense coatings of 1 to 10 micrometers can be made which have thermal cycle durabilities enhanced by the inverse of this ratio.
A method for depositing a coating of a dense ceramic material is disclosed. The coating may be an oxide or other refractory ceramic material. A ceramic starting material is melted and refined by heating with an electron beam in vacuum. The refined material is evaporated and deposited on a heated substrate to form a dense ceramic coating. In particular, a durable ceramic thermal barrier coating on a superalloy turbine part may be formed by coating the part with a metal layer which is oxidized to form alumina and depositing a dense ceramic layer followed by an overcoating of a columnar ceramic material.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "This is a continuation of Ser.", "No. 504,651, filed June 15, 1983.", "FIELD OF THE INVENTION The invention is in the field of ceramic coatings on substrates.", "The substrates may be metal or nonmetal, homogenous or composite materials.", "The invention has particular application for protective coatings for turbine engine components.", "Significant improvements in durability and high temperature capability of combustion zone parts are possible.", "BACKGROUND ART U.S. Pat. No. 4,321,311 to Strangman describes a composite coating system for thermal barrier ceramic coatings on metal parts.", "The system has three interrelated elements.", "(1) a metallic layer of an alumina forming metal, such as MCrAlY alloy where M is Ni, Co, NiCo, Fe or other metals, (2) a continuous adherent alumina layer formed on the metallic layer, and (3) a discontinuous ceramic layer having a particular columnar morphology on the alumina layer.", "The ceramic layer has columnar grains, oriented substantially perpendicular to the surface of the substrate and having free surfaces extending down to the alumina layer.", "The voids between the individual ceramic columns enlarge and diminish to accommodate strains arising because of the differential thermal expansion between the metallic and ceramic materials.", "This patent teaches deposition cf the columnar ceramic coating by positioning the substrate over an electron-beam heated pool of molten ceramic in vacuum.", "The substrate temperature was maintained in the range 1000° to 1500° F. to provide a relatively coarse columnar structure.", "In order to assure that the ceramic coating contained the stoichiometric amount of oxygen, the dark, as-deposited ceramic was heat treated at about 1600° F. for 32 hours in an oxygen containing atmosphere so that the color lightened to a shade typical of the stoichiometric ceramic.", "A closely related U.S. Pat. No. 4,321,310 to Ulion and Ruckle, teaches polishing of the interface between the metallic layer and the alumina layer to provide a surface roughness of less than about 25 microinches RMS average.", "This increases the adherence of the columnar ceramic layer and, thus, increases the cyclic temperature durability of the coating system.", "The prior art also teaches the deposition of ceramic materials, such as yttria, by electron-beam heated evaporation of a metal or alloy vapor in the presence of oxygen.", "See, for example, R. F. Bunshah, "Structure/property relationships in evaporated thick films and bulk coatings", J. Vac.", "Sci.", "Technol.", "Vol. 11, p. 633-39, July/Aug 1974.", "SUMMARY OF THE INVENTION In the present invention, a layer of dense substoichiometric ceramic material is deposited on a substrate.", "The coating may be an oxide, nitride, carbide, boride, silicide or other refractory ceramic material.", "A ceramic starting material is refined and probably chemically reduced by heating with an electron beam in vacuum.", "This material becomes substoichiometric because of the evolvement of oxygen, nitrogen or other reactive gas.", "The refined, substoichiometric material is then evaporated in vacuum and deposited on a heated substrate to form a dense, substoichiometric ceramic layer.", "The object to be coated may be a metal or non-metal, but for proper adherence it must have a stable ceramic surface which is chemically and mechanically compatible with the ceramic coating to be applied.", "In the case of a metal object, the object may be covered with ceramic-forming metal layer which is then converted to a ceramic layer by heating the object in an atmosphere containing the appropriate reactive gas.", "In particular, for a superalloy turbine part, the object may be coated with an alumina forming layer and heated in a residual air atmosphere.", "If desired, an overcoating of columnar, substantially stoichiometric ceramic material can be formed by reactively depositing a ceramic vapor in the presence of oxygen or other reactive gas component of the ceramic.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional line drawing illustrating a coating system according to the invention.", "FIG. 2 is a scanning electron microscope photomicrograph (approximately 5000×magnification) showing a cross section of a sample of an experimental coating system according to the invention.", "FIG. 3 is a composite of four transverse electron microscope photomicrographs showing a cross section of a sample of an experimental coating system.", "The scale is indicated in the figure.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a coating system for a metal part according to the invention.", "The base material 1 is coated with an alumina forming metallic layer 2 on which an alumina containing oxide layer 3 is formed.", "The layer of dense ceramic material 4 is formed on the oxide layer 3, and the columnar, substantially stoichiometric ceramic material 5 is formed on the dense ceramic layer.", "The density of the material of layer 4 is preferably greater than 94%, typically 96%, of the maximum theoretical density of the ceramic material.", "Open porosity typically disappears at about 94% theoretical density.", "The latter is about 6 g/cm 3 for zirconia stablilized with 20 weight percent yttria (ZrO 2 with 20% Y 2 O 3 ).", "The density of the columnar ceramic material 5 is typically 50 to 90% of the theoretical maximum value.", "FIG. 2 is a scanning electron microscope photomicrograph showing a polished cross-sectional sample of a coating system of the type illustrated in FIG. 1. The base material is a superalloy which was polished to surface roughness 40 to 50 micrometers (15 to 20 microinches) RMS and coated with a layer 12 of NiCrAlY on which an alumina containing oxide layer 13 was formed.", "The nominal NiCrAlY composition was Ni (remainder), 22% Cr, 12% Al, and 0.3% Y. The dense ceramic material 14 and the columnar ceramic material 15 are both ZrO 2 with 20% Y 2 O 3 .", "Note that the layer of dense ceramic material 14 bridges over the surface defect 19 caused by a spit of ZrO 2 or Y 2 O 3 from the coating source.", "A preferred process for depositing a ceramic coating on a metallic substrate will now be described.", "Typically, the base article is composed of a metal alloy, such as stainless steel 302, or Inconel 718, or a superalloy, such as Ni or Co base, Cr containing alloys, known as Waspalloy, MAR-M-247 or PWA 1455.", "The surface is polished, preferably to a surface roughness of 10 to 250 nm(0.5 to 10 microinches) RMS average.", "The polishing may be accomplished by mechanical grinding and polishing, perhaps in conjunction with abrasive slurry or electrochemical polishing techniques.", "The polished surface is cleaned by appropriate processes, such as vapor honing and ultrasonic techniques.", "The polished article is coated with a metallic layer of an alumina (Al 2 O 3 ) forming material, such as Al, Ni 3 Al or MCrAlY, by an appropriate process.", "This may be done by physical vapor deposition, low pressure plasma spray, sputtering, or pack diffusion.", "This metallic coating typically has a thickness of 0.12 mm (0.005 inches), but thicknesses in the range from 0.5 micrometers to 10 mm (2×10 -5 to 0.5 inches) may be appropriate depending upon the application.", "In addition, intermediate layers between the alumina forming metal coating and the metal base may be used.", "The coated base is glass bead peened in a conventional manner, preferably with new glass beads at a pressure of 0.3 to 0.4 MPa (50 to 60 pounds per square inch).", "The part is then thoroughly cleaned ultrasonically and degreased, preferably in a flurocarbon liquid which does not contain a drying agent.", "The part is mounted on an appropriate fixture and introduced into a first chamber or load lock of a vacuum coating system.", "The load lock is evacuated to a suitable pressure, such as less than 10 -3 torr.", "Radiant or electron beam heaters preheat the article and maintain its temperature at a value between 870° and 1100° C. (1600° and 2000° F.) for a time between 10 and 30 minutes so as to dry, degas, and evaporatively clean the surface.", "During this time, the alumina forming material is oxidized to form a layer of mixed metal oxides having a typical thickness of 0.5 to 2 micrometers.", "Of course, if the alumina forming material 12 is simply Al, the alumina containing layer 13 is just alumina and not mixed metal oxides.", "FIG. 3 illustrates the possible complexity of the alumina containing oxide layer 13 of the sample of FIG. 2. It is believed that when oxidation begins, a porous layer of mixed metal oxides forms on the surface 17 of the layer 12 of the alumina forming metal coating.", "The various metal components of the mixed oxides are in approximately the same relative quantities as in the metal layer 12.", "As oxidation continues, aluminum oxide grains form and grow until they form a continuous, dense alumina layer 13a having a thickness of 0.25 to 0.5 micrometers.", "The continuous alumina layer forms an oxygen barrier and stops further oxidation.", "The dense alumina and the porous metal oxide layers have a definite interface 16.", "The dense zirconia layer 14 is deposited directly on the surface 18 of the remaining porous layer 13b of mixed metal oxides.", "The ceramic material to be vaporized is heated by an electron beam in a chamber which is constantly pumped to evacuate it.", "The material is melted in a crucible and brought to a temperature where it is refined and probably chemically reduced.", "The appropriate temperature range depends upon the material and is not known precisely.", "For ZrO 2 stabilized with 20 weight percent Y 2 O 3 , the preferred temperature is believed between 1800° and 2000° C. (3270° and 3630° F.).", "A suitable operating temperature is obtained by setting the electron beam power just below that which produces rapid evaporation.", "A radiant heater is used to heat the walls and outgas the chamber.", "The refining and reducing step is continued for several minutes until a quantity of substoichiometric ceramic material is produced near the heated surface.", "This may be indicated by a reduction in the system pressure to a low value, such as 5×10 -5 torr, as the quantity of oxygen or other reactive gas evolved from the material declines.", "The substoichiometric ceramic liquid is black and glassy and has a high density, believed greater than about 96% of the theoretical maximum for the ceramic material.", "Enough of the dense substoichiometric material must be available to provide a dense layer of the desired thickness on the substrate.", "A vapor shield or shutter covers the crucible until coating actually begins.", "The part to be coated is transferred into the evacuated chamber and positioned over the covered crucible at an appropriate distance.", "The substrate is rotated at a rate, preferably greater than 10 revolutions per minute (rpm).", "The substrate temperature is maintained at a value between 900° and 1200° C. (1650° and 2200° F.) by a radiant or other heater.", "The chamber pressure is preferably 10 -4 torr or less.", "A pressure of less than 2×10 -5 torr is even more preferred.", "When all is ready, the electron beam power is increased to a value which provides rapid evaporation.", "A coating deposition rate of between 10 nm/min.", "and 25 micrometers/min.", "is preferred.", "A rate of 500 nm/min.", "or less is preferred for maximum density.", "When coating is to begin, the crucible is uncovered and the part is exposed to the substoichiometric vapor for a length of time suitable to provide a layer of dense ceramic coating having the desired thickness.", "This thickness must be sufficient to provide a continuous covering of the substrate surface, but less than the thickness which would yield a residual stress of formation greater than the strength of the ceramic coating or the strength of the ceramic coating-substrate interface.", "At minimum radius of curvature, the thickness of the dense ceramic coating is preferably less than about 10 times the minimum radius of curvature.", "Minimum radii of curvatures of 12 micrometers to 1.2 mm (0.0005 to 0.05 inches) are frequently used in turbine engine components.", "For maximum thermal cycle durability the thickness is preferably 2 to 10 times greater than the RMS average surface roughness of the substrate.", "Useful coating thicknesses of between 1 nm and 10 mm appear possible.", "After the dense substoichiometric layer is formed, oxygen is introduced into the coating chamber to maintain a suitable pressure, preferably between 0.5 and 2 millitorr, but pressures in the range 0.1 to 10 millitorr may be useful at times.", "Tubes and nozzles are used to direct the oxygen gas to impinge upon the substrate.", "Use of an automatic flow valve is preferred in order to maintain precise control.", "The pressure of all other gases is preferably less than 10% of the total pressure.", "Introduction of oxygen gas increases the oxygen content of the dense ceramic layer and initiates formation of a columnar, substantially stoichiometric ceramic.", "The oxygen flow rate is proportional to the rate of deposition.", "The substrate temperature is preferably maintained at a constant value in the range of 540° to 1200° C. (1000° to 2200° F.).", "The electron beam power and substrate rotation rates are comparable to those for depositing the dense ceramic layer.", "When the desired thickness of columnar ceramic has been obtained, the vapor source is covered, the electron beam power is reduced, the oxygen flow is halted, and the substrate heater turned off.", "The coated article is withdrawn into the load lock and cooled to approximately 150° C. (300° F.) before it is removed from the vacuum system.", "Increased adhesion can be obtained by annealing the coated part from 10 minutes to several hours in an air furnace at a temperature 55° to 280° C. (100° to 500° F.) above the temperature maintained during formation of the columnar ceramic.", "The density of the ceramic layers increases with the substrate temperature during deposition and decreases as the deposition rate increases.", "It has been observed that the ratio of coating density to theoretical maximum density increases almost linearly as the substrate rotation rate increases from 10 to 50 rpm.", "Reciprocal and other types of substrate motion are possible.", "An average substrate speed of greater than 76 cm/min.", "(30 inches per minute) is preferred for uniformity and maximum density.", "The specific electron beam powers necessary for refining and deposition depends upon many factors but are easily determined by experiment.", "For ZrO 2 in a circular cruciable 10 cm (4 inches) in diameter where the onset of rapid evaporation is typically about 12 kW, refining is done at about 10 kW and deposition at about 20 kW.", "Dense ceramic layers deposited according to the invention have an extremely fine grain size.", "As is indicated in FIG. 3, the grains have an initial average width perpendicular to the growth direction of less than about 100 nm.", "Such small grain sizes are preferred for maximum adherence to the substrate.", "In known prior ceramic layers, the initial average width is typically 500 nm or more.", "EXAMPLE 1 A ceramic coating was applied to a first-stage turbine blade for a gas turbine engine.", "The superalloy blade was approximately 10×4×4 cm (4×1.5×1.5 inches) in size and had an airfoil region to be coated having a radii of curvature ranging down to about 25 micrometers (0.001 inches).", "The part was cleaned by a vapor honing process and coated with a layer of CoCrAlY by a conventional electron-beam heated evaporation process similar to that described in U.S Pat. No. 3,798,055.", "The CoCrAlY coating had a nominal thickness of 0.12 mm (0.005 inches) and a nominal composition of Co (remainder), 21% Cr, 12% Al, and 0.3% Y. After application of the CoCrAlY coating, the part was glass bead peened and then heat treated in a dry hydrogen atmosphere at a temperature of 980° C. (1800° F.).", "After these preliminary steps, the part had an average surface roughness of approximately 0.001 mm (60 microinches) RMS average on the curved surfaces which were to be coated.", "The part was fixtured on a rotatable shaft and introduced into a load lock which was then evacuated to a pressure of approximately 2×10 -4 torr.", "The part was introduced into a vacuum furnace chamber and rotated at 12 rpm while it was heated by a radiant heater to a temperature of about 980° C. (1800° F.) for about 10 minutes to form a 1 to 2 micrometer thick layer of alumina containing metal oxide on the surface.", "During this time, a compressed ingot of white, porous pellets of ZrO 2 stabilized by 20 weight percent Y 2 O 3 was melted and refined in an electron beam in a circular crucible having a diameter of 10 cm (4 inches) positioned about 20 cm (8 inches) below the part.", "The pressure in the furnace chamber was about 2×10 -4 torr and a radiant heater over the crucible heated a witness substrate to about 980° C. (1800° F.).", "The electron beam power was just below that for the onset of rapid evaporation.", "To begin coating, the electron beam power was increased to about 30 kW and the crucible uncovered to expose the rotating part to the vapor.", "The part was coated for approximately 90 seconds to deposit a dense, substoichiometric ceramic layer having an estimated thickness of approximately 45 micrometers.", "After 90 seconds, oxygen was introduced into the chamber to provide a partial pressure of between 0.5 and 1 millitorr.", "The part continued to rotate at approximately 12 rpm for approximately 30 minutes so as to deposit a columnar ceramic layer having a thickness of approximately 0.1 mm (0.005 inches).", "The finished part was returned to the load lock and cooled before being removed from the vacuum system.", "This part was tested for cyclic heating and cooling by moving it into and out of an air furnace maintained at about 1000° C. (1830° F.) with a cycle time of 10 minutes.", "The part survived approximately 500 cycles with no spauling or delamination before failure occurred.", "Other parts were coated by a similar process except that the duration of the time of the exposure of the part to the substoichiometric vapor before the introduction of oxygen into the chamber was varied from about 3 to 90 seconds.", "The results of thermal cycle testing of these parts is shown in Table I. TABLE I______________________________________ Substoichiometric Thermal CyclesRun # Coating Time to Failure______________________________________157,166 3 sec.", "0160 19 161*161 19 2016159 43 500165 60 432 -158 90 500164 Entire 1______________________________________ *Equipment failure The thickness of the dense layer is determined by the length of time of exposure to the substoichiometric ceramic vapor before introduction of the reactive gas.", "From the data of Table I, it is clear that the optimum time was approximately 19 seconds under the conditions prevailing.", "This corresponded to a thickness of approximately 10 micrometers for the dense, substoichiometric layer.", "EXAMPLE 2 A part similar to those of Example 1 was coated by a process similar to that of Example 1 except that it was not heat treated in dry hydrogen.", "The coating interval before oxygen gas was introduced was 19 seconds, the approximate optimum value determine from Table 1.", "This part survived 4000 cycles of the thermal test.", "Non-metallic substrates may also be coated.", "The substrate may be elemental, such as carbon graphite;", "single crystalline ceramic, such as sapphire or silicon nitride;", "polycrystalline ceramic, such as quartz or alumina;", "or an amorphous material, such as glassy SiO 2 or boro-alumina silicates.", "Dense ceramic coatings of Al 2 O 3 , SiN and SiO 2 have been applied to ceramic substrates.", "The surface of a ceramic substrate is preferably polished to a surface finish that is limited by the homogeniety of the substrate material.", "This can be done by the processes mentioned in the case of metallic substrates or by fire polishing in an inert or reactive media, or by reactive ion etching.", "Depending upon the polishing scheme, drying and ultrasonic cleaning may be preferred to remove polishing media or chemical residue.", "The substrate is mounted on an appropriate fixture, and introduced into a load lock, and heated, by radiant and or electron beam means, for a time between 10 and 30 minutes, preferably to a temperature just below its weakening or melting point.", "Substrate outgassing may require a longer time.", "During this time, reactive ion etching or sputtering from the sample may be performed, if required to complete surface preparation.", "Selective gas reactions or electron beam impingement may also be used to modify the chemical and structural makeup of the substrate surface.", "Preparation of a special alumina containing layer is generally unnecessary for a non-metallic substrate.", "The preferred procedure for depositing the dense, layer is also similar to that described for metallic substrates.", "For ceramic substrates, the substrate adhesion, density and strength of the dense ceramic coating layer can be improved by depositing at a formation temperature just below the melting point of the substrate or coating, whichever is lower.", "If desired, the dense ceramic coating can be made substantially stoichiometric or a columnar ceramic overcoat can be made by introducing the appropriate reactive gas following deposition of the dense layer.", "The thickness of the dense ceramic layer can be substantially greater on a ceramic substrate than on a metallic substrate because the difference in thermal expansion coefficients of coating and substrate will normally be much less.", "Hence, dense erosion and abrasion resistant ceramic coatings having thickness of 10 to 100 micrometers can be manufactured which have thermal cycle durability equivalent to much thinner coatings on metallic substrates;", "thinner by the ratio of the thermal expansion coefficient of the ceramic substrate to that of the metallic substrate.", "Alternatively, thin dense coatings of 1 to 10 micrometers can be made which have thermal cycle durabilities enhanced by the inverse of this ratio." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This patent application claims priority from U.S. Provisional Application No. 61/916,643, (TI-74614) filed Dec. 16, 2013; U.S. Provisional Application No. 61/916,655 (TI-74615); and U.S. Provisional Application No. 61/916,669 (TI-74616) filed Dec. 16, 2013, which are incorporated herein by reference in their entirety for all purposes. This application is related to U.S. application Ser. No. XX/XXX,XXX (TI-73620); U.S. application Ser. No. XX/XXX,XXX (TI-74615); and U.S. application Ser. No. XX/XXX,XXX (TI-74616), filed on even date, which are incorporated herein by reference in their entirety for all purposes. FIELD [0002] The invention relates to recovery of data or commands in a signal stream received from a wireless power receiver in a wireless power transmitter. BACKGROUND [0003] The explosion of small portable electronic devices such as cell phones has led to the desire to be able to recharge the device without the necessity of attaching a cord to the device. A solution that accomplishes this task is known as “wireless power”. The term “wireless power” as utilized herein refers to the transmission of electrical energy from a power source to an electrical load without interconnecting wires. A common form for wireless power transmission utilizes two electromagnetically coupled coils to form a transformer through which power is transferred from the primary side to the receiving side. The transmitter may take the form of a pad having a coil embedded therein. The receiver may be built into a cellular telephone, for example, with the receiving side coil built into the back thereof. Although there is no direct contact between the transmitting and receiving coils, the close proximity of the coils and the judicious use of shielding allows for efficient transfer of energy from the transmitting side to the receiving side to operate a load, which may be a rechargeable battery being recharged by the system, for example. [0004] FIG. 1 shows a block diagram of a prior art wireless power transmission system, generally as 100 . The system comprises a transmitter side 102 and a receiver side 122 . The transmitter side 102 comprises a circuit 104 for rectifying an AC input into a DC voltage which is fed into a power stage 106 for generating a high frequency signal. The high-frequency signal is coupled across a transformer 120 to the receiver side 122 . The power stage 106 is controlled by controller 108 which could be combined into a single integrated circuit with the power stage 106 . The receiver side 122 comprises a rectifier circuit 124 to output a DC voltage and a voltage conditioning circuit 126 which is operated by the receiver controller 128 to supply power to a load 130 , which may be a rechargeable battery being recharged by the system, for example. [0005] As shown FIG. 1 , power flows from left to right from the transmitter to the receiver and communications flows from right to left from the receiver to the transmitter. The communication signals may be command signals to adjust the power level from the transmitter or other parameters, for example. The communication signals may be generated by coupling a resistor or capacitor across the receiving coil to generate signals which can be recognized by the controller on the transmitting side. The low-level signals are noisy because of the noise generated by the power transmission portion of the system. [0006] The Wireless Power Consortium (WPC) defines a standard for such wireless power transmission. In a WPC defined wireless charging system, the power transmitter detects the signal from the power receiver as a modulation of current through and/or voltage across the primary circuit through a V/I circuit 110 . In other words, the power receiver and the power transmitter use amplitude modulated power signals to provide a power receiver to power transmitter communication channel. [0007] The WPC defined communication channel assumes that the incoming power signal is always amplitude modulated. However, that may not be a valid assumption. Accordingly, there is a need for a reliable, low-cost and easily integratable solution for detecting information being sent from the receiver to the transmitter in a wireless power system. SUMMARY [0008] It is a general object of the invention to provide for recovery of data or commands in a signal stream in a wireless power transmitter. [0009] In an aspect, in a primary side wireless power transmitter for being inductively coupled to a secondary side wireless power receiver for supplying power to the wireless power receiver to power a load coupled to the wireless power receiver, a primary side control for receiving communications from the secondary side wireless power receiver through the inductive coupling comprises a primary side tank circuit being excited into oscillation by an excitation signal, the tank circuit receiving a signal from the secondary side wireless power receiver. A delay circuit generates a fixed delay clock signal from the excitation signal. A sample and hold circuit samples a tank circuit voltage utilizing the fixed delayed clock signal. A comparator is coupled to an output of the sample and hold circuit for extracting data or commands from the signal stream. [0010] In an aspect, a method of operating a primary side wireless transmitter inductively coupled to a secondary side wireless power receiver for supplying power to the wireless power receiver to power a load coupled to the receiver comprises exciting a tank circuit into oscillation utilizing an excitation signal. A signal stream is received from the wireless power receiver in a primary side tank circuit. A fixed delay clock signal is generated. The tank circuit voltage is sampled utilizing the fixed delayed clock in holding the sample value. A threshold voltage signal is generated from the signal stream signal. Data is extracted from the signal stream utilizing the threshold voltage signal. [0011] In an aspect, a wireless power transfer system comprises a transmitter for transmitting electrical energy through a first inductive coil electromagnetically coupled to a second inductive coil and a receiver. A circuit in the receiver couples a resistor or capacitor across the second inductive coil to generate data or command signals in the first inductive coil. A sample and hold circuit samples a value of signal in the first inductive coil and holds the value, the sample being taken at a fixed delay from the excitation signal for the first coil. A comparator coupled to an output of the sample and hold circuit extracts data or commands from a signal stream. BRIEF DESCRIPTION OF DRAWINGS [0012] Further aspects of the invention will appear from the appending claims and from the following detailed description given with reference to the appending drawings. [0013] FIG. 1 is a diagram of a wireless power system according to the prior art; [0014] FIG. 2 is a graph showing the tank waveform in a wireless power system; [0015] FIG. 3 is a graph showing the tank waveform in which the two signals in a wireless power system have the same amplitude; [0016] FIG. 4 is a block diagram of an embodiment constructed according to the principles of the present disclosure; [0017] FIG. 5 shows an alternate embodiment constructed according to the principles of the present disclosure; and [0018] FIGS. 6-12 show waveforms for the circuits illustrated in FIGS. 4 and 5 . DETAILED DESCRIPTION [0019] In order to have a reliable communication channel, the system must tolerate system parameter variations including variations in the coupling coefficient (K) of between 0.2 and 0.7, and variation in the receiver load from 5 ohms to 1 kilo ohm, transmit and receive coil inductance variation due to shielding, effects of the battery effects of a magnet used to center the receiving device on the transmitting pad and manufacturing tolerances over the entire range of operating frequency from 110 kHz to 205 kHz. [0020] The WPC defined communication channel assumes that the incoming signal is always amplitude modulated. However, the present inventors have discovered that this information may be lost because of its low value (i.e. 200 mV) which may be further reduced when the power signal level (which can be 70 Vpp) is divided down to a voltage level that can be handled by an integrated circuit, as this signal, which rides on the power signal, will also be reduced. This low level signal can be masked by changes in the load current. Accordingly, the inventors have determined that the signal data may lie within the phase of incoming carrier signal, rather than the amplitude. Therefore, a traditional amplitude demodulator channel is inadequate to solve the problems described above. [0021] FIG. 2 shows the tank signal waveform of the power transmitter where data is being sent from the receiver to the transmitter, generally as 200 . In FIG. 2 , the load resistance is 100 ohms, the coefficient of coupling K is 0.7, the secondary (receiver) side capacitor, utilized to transmit data or commands back to the transmitter (primary) side, is 22 nF. The primary side inductance is 9.36 μH and the secondary side inductance is 16 μH with the circuit having an operating frequency of 155 kHz. Waveform 202 is without the capacitor being coupled across the secondary side of receiver coil and the waveform 204 shows the same signal with the capacitor coupled across the secondary side receive coil to transmit information. Under these circumstances, there is a difference in amplitude between the two waveforms and the information in the signal can be amplitude detected. [0022] FIG. 3 shows the tank signal waveform of a power transmitter generally as 300 . In FIG. 3 , the load resistance is 5 ohms, the coupling coefficient is 0.2, the capacitance is 22 nF, the primary side inductor is 9.36 μH, the secondary side inductor is 16 μH and the operating frequency is 155 kHz. As can be seen, the peaks of the waveforms with and without capacitance being switched in at the secondary side, are identical at 306 . The exploded view shows the signal 302 which is the signal without the capacitor being switched in across the receiver side coil and the signal 304 which shows the capacitor switched in across the coil. Therefore, it may be very difficult to detect the data when the signal peaks are essentially identical utilizing amplitude demodulation. [0023] FIG. 4 shows an embodiment of a solution to this problem generally as 400 . In FIG. 4 , the tank waveform from the transmitter side tank circuit is coupled via resistor divider 402 , 404 to a capacitor 406 . The resistor divider 402 , 404 divides of the voltage across the tank circuit, which may be as much as 70 V peak to peak, to a voltage level that can be handled by an integrated circuit. Capacitor 406 blocks the DC level of the input waveform from affecting the setpoint of a buffer circuit 412 , the non-inverting input of which is coupled to the capacitor 406 . This allows the setpoint of the buffer 412 to be set via the resistor divider 408 , 410 between a reference voltage and ground. The inventors have found it to be advantageous to utilize the voltage just slightly above 0 V, for example, 100 or 200 mV as the setpoint for the buffer 412 . In addition, the circuit may be operated at a higher voltage than may be used for other portions of the transmitter circuit, for example 4 V rather than 3.3 V. The combination of these two features allows for an increased voltage swing of the measured data or commands in the signal stream. Buffer 412 has its output coupled to the inverting input thereof so that it has a gain of unity. The output of buffer 412 is coupled to a sample and hold circuit having a switch 414 which stores the value of the tank waveform, after having been buffered by buffer 412 , and stored in capacitor 416 . The switch 414 in the sample and hold circuit is controlled by the output of the 300 ns pulse generator 430 having a fixed phase delay of 60°. This circuit 430 is driven, in turn, by the excitation signal 426 used to excite the tank circuit in the transmitter via buffer inverter 428 . Therefore, the sample of the tank waveform is taken at fixed phase delay of 60° from the excitation signal for the tank waveform. The sample value is stored in capacitor 416 which is coupled between the switch and ground. Voltage across capacitor 416 is filtered by a low pass filter 418 , here in a fifth order Butterworth low pass filter. The output of the low pass filter 418 is coupled to the inverting input of an auto zero or low offset comparator 424 . The output of the low pass filter 418 is also coupled through RC filter 420 , 422 to the non-inverting input of auto zero comparator 424 . The resistor 420 is coupled in series between the output of the low pass filter 418 and the non-inverting input of auto zero comparator 424 . The capacitor is connected between the non-inverting input of the auto zero comparator 424 and ground. The output of auto zero comparator 424 is the data or command signal. It should be noted that the fixed phase delay can range at least between 15° and 75° without departing from the principles of the present disclosure. [0024] In operation, the coil voltage from the transmit coil in the transmit tank circuit can be sensed directly. This voltage, which can be as high as 70 V peak to peak the varying DC level, is AC coupled to the demodulator signal chain through a resistor divider 402 , 404 which reduces the voltage to level it can be handled by an integrated circuit. Depending upon the voltage reduction of the resistor divider 402 , 404 , the signal to be detected can be 100 mV or lower riding on top of the 10-70 V peak to peak carrier amplitude. Thus it has a very low signal-to-noise ratio (SNR). In addition, the carrier has both positive and negative swings with respect to ground. Therefore, the present invention maximizes the signal amplitude by setting the DC setpoint at the input of amplifier 412 very close to ground, for example 200 mV. This, along with a higher voltage (for example for 4 V) supply for the amplifier 412 allows for a signal swing of almost 4 V. [0025] The input voltage to the non-inverting terminal of buffer amplifier 412 is shown in FIG. 6 , generally as 600 . [0026] As can be seen, it is an amplitude (or phase) modulated sine wave of frequency between 110 kHz-205 kHz. The amplitude modulation frequency is 2 kHz. The 600 shows two periods; one just before the modulation and one after the modulation. [0027] The output of buffer amplifier 412 is shown in FIG. 7 as a half wave rectified sine wave 700 . FIG. 8 shows the square wave excitation signal 800 is used to excite the tank circuit in the transmitter side of the power transmission device. This signal is sometimes referred to as a “PWM” signal although it is normally a square wave having a 50% duty cycle. However, under extreme light load conditions, the cycle would be cut back from the 50% level to 10% level in order to reduce the power generated when the need for power at the receiver side is low. FIG. 9 shows the output pulse from the 300 ns pulse generator having a fixed phase delay of 60° generally as 900 . Pulse 900 is coupled to the switch 414 of the sample and hold circuit and used to operate the switch to take samples of the output of buffer 412 . The samples are held in capacitor 416 . [0028] The sampled voltage is shown in FIG. 10 generally as 1000 . In order to remove high-frequency noise from the signal, it is passed through a low pass filter, here a fifth order Butterworth low pass filter 418 . The output of the Butterworth low pass filter is shown in FIG. 11 generally as 1100 . In order to determine the threshold utilized to extract data or commands from signal stream, an RC filter comprising resistor 420 coupled in series between the output of the fifth order Butterworth low pass filter and the non-inverting input of auto zero comparator 424 and a capacitor 422 coupled from the non-inverting input of amplifier 424 to ground is utilized. The threshold 1102 generated by the low pass filter 420 , 422 is utilized to extract the data which appears at the output of the auto zero comparator 424 . The signal 1106 represents a digital zero and the signal 1104 represents a digital one. The signal 1200 is the output of auto-zero comparator 424 , with a digital one output being shown at 1202 . [0029] FIG. 5 shows an alternative embodiment of a solution to this problem generally as 500 . In FIG. 5 , the tank waveform from the transmitter side tank circuit is coupled via resistor divider 502 , 504 to a capacitor 506 . The resistor divider 502 , 504 divides the voltage across the tank circuit, which may be as much as 70 V peak to peak, to a level that can be handled by an integrated circuit. Capacitor 506 blocks the DC level of the input waveform from affecting the setpoint of a buffer circuit 512 , the non-inverting input of which is coupled to the capacitor 506 . This allows the setpoint of the buffer 512 to be set via the resistor divider 508 , 510 between a reference voltage and ground. The inventors have found it to be advantageous to utilize the voltage just slightly above 0 V, for example, 100 or 200 mV as the setpoint for the buffer 512 . In addition, this circuit is operated at a higher voltage than may be used for other portions of the transmitter circuit, for example 4 V rather than 3.3 V. The combination of these two features allows for an increased voltage swing of the measured data or commands in the signal stream. Buffer 512 has its output coupled to the inverting input thereof so that it has a gain of unity. The output of buffer 512 is coupled to a switch of sample and hold circuit 514 . The sample and hold circuit 514 is operated by a pulse from pulse generator 530 at a fixed time delay, here shows 1.2 μs. Other time delays can be utilize such as 250 ns to 1.2 μs. Pulse generator 530 is operated by the excitation signal for the tank circuit 526 passing through buffer inverter 528 . This signal is sometimes referred to as a “PWM” signal although it is normally a square wave having a 50% duty cycle. However, under extreme light load conditions, the cycle would be cut back from the 50% level to the 10% level in order to reduce the power generated when the need for power at the receiver side is low. A sample value is stored in capacitor 516 which is coupled between the switch and ground. [0030] The voltage across capacitor 516 is filtered by a low pass filter 518 . In this embodiment a fifth order Butterworth low pass filter is utilized. The output of the Butterworth low pass filter is shown in FIG. 11 generally as 1100 . In order to determine the threshold utilized to extract data or commands from signal stream, an RC filter comprising resistor 520 coupled in series between the output of the fifth order Butterworth low pass filter and the non-inverting input of auto zero comparator 524 and a capacitor 522 coupled from the non-inverting input of amplifier 524 to ground is utilized. The threshold 1102 generated by the low pass filter 520 , 522 is utilized to extract the data which appears that the output of the auto-zero comparator 524 . The signal 1106 represents a digital zero and the signal 1104 represents a digital one. The signal 1200 is the output of auto-zero comparator 524 , with a digital one output being shown at 1202 . [0031] The fixed time delay could be 250 ns to 1.2 μs, for example. The pulse generated by the time delay circuits may be 300 ns wide, for example. These circuits are somewhat simpler in construction than a phase delayed pulse generator circuit. Circuits capable of generating such time delayed pulses are well known in the art and need not be discussed further herein. A circuit for the generation of the phase delayed signals can be found in commonly-own application (TI-74615) filed on even date and incorporated herein by reference in its entirety for all purposes. Details on an alternate threshold detection circuit to replace the RC circuit 420 , 422 or 520 , 522 can be found in commonly-owned applications (TI 73620 or TI-74615) filed on even date and incorporated herein by reference in their entirety for all purposes. [0032] Although the invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made thereto without departing from the spirit and scope of the invention as defined by the appended claims.
A primary side wireless power transmitter inductively couplable to a secondary side wireless power receiver for receiving communications from the secondary side wireless power receiver through the inductive coupling having a primary side tank circuit receiving a signal from the secondary side wireless power receiver. A phase delay or time delay circuit generates a fixed delay clock signal from a signal utilized to excite the primary side tank circuit. A sample and hold circuit samples a tank circuit voltage utilizing the fixed phase or time delayed clock signal. A comparator is coupled to an output of the sample and hold circuit for extracting data or commands from the signal stream. A method of operating a primary side wireless transmitter inductively coupled to a secondary side wireless power receiver for supplying power to the wireless power receiver to power a load coupled to the receiver is also disclosed.
Summarize the key points of the given document.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This patent application claims priority from U.S. Provisional Application No. 61/916,643, (TI-74614) filed Dec. 16, 2013;", "U.S. Provisional Application No. 61/916,655 (TI-74615);", "and U.S. Provisional Application No. 61/916,669 (TI-74616) filed Dec. 16, 2013, which are incorporated herein by reference in their entirety for all purposes.", "This application is related to U.S. application Ser.", "No. XX/XXX,XXX (TI-73620);", "U.S. application Ser.", "No. XX/XXX,XXX (TI-74615);", "and U.S. application Ser.", "No. XX/XXX,XXX (TI-74616), filed on even date, which are incorporated herein by reference in their entirety for all purposes.", "FIELD [0002] The invention relates to recovery of data or commands in a signal stream received from a wireless power receiver in a wireless power transmitter.", "BACKGROUND [0003] The explosion of small portable electronic devices such as cell phones has led to the desire to be able to recharge the device without the necessity of attaching a cord to the device.", "A solution that accomplishes this task is known as “wireless power.”", "The term “wireless power”", "as utilized herein refers to the transmission of electrical energy from a power source to an electrical load without interconnecting wires.", "A common form for wireless power transmission utilizes two electromagnetically coupled coils to form a transformer through which power is transferred from the primary side to the receiving side.", "The transmitter may take the form of a pad having a coil embedded therein.", "The receiver may be built into a cellular telephone, for example, with the receiving side coil built into the back thereof.", "Although there is no direct contact between the transmitting and receiving coils, the close proximity of the coils and the judicious use of shielding allows for efficient transfer of energy from the transmitting side to the receiving side to operate a load, which may be a rechargeable battery being recharged by the system, for example.", "[0004] FIG. 1 shows a block diagram of a prior art wireless power transmission system, generally as 100 .", "The system comprises a transmitter side 102 and a receiver side 122 .", "The transmitter side 102 comprises a circuit 104 for rectifying an AC input into a DC voltage which is fed into a power stage 106 for generating a high frequency signal.", "The high-frequency signal is coupled across a transformer 120 to the receiver side 122 .", "The power stage 106 is controlled by controller 108 which could be combined into a single integrated circuit with the power stage 106 .", "The receiver side 122 comprises a rectifier circuit 124 to output a DC voltage and a voltage conditioning circuit 126 which is operated by the receiver controller 128 to supply power to a load 130 , which may be a rechargeable battery being recharged by the system, for example.", "[0005] As shown FIG. 1 , power flows from left to right from the transmitter to the receiver and communications flows from right to left from the receiver to the transmitter.", "The communication signals may be command signals to adjust the power level from the transmitter or other parameters, for example.", "The communication signals may be generated by coupling a resistor or capacitor across the receiving coil to generate signals which can be recognized by the controller on the transmitting side.", "The low-level signals are noisy because of the noise generated by the power transmission portion of the system.", "[0006] The Wireless Power Consortium (WPC) defines a standard for such wireless power transmission.", "In a WPC defined wireless charging system, the power transmitter detects the signal from the power receiver as a modulation of current through and/or voltage across the primary circuit through a V/I circuit 110 .", "In other words, the power receiver and the power transmitter use amplitude modulated power signals to provide a power receiver to power transmitter communication channel.", "[0007] The WPC defined communication channel assumes that the incoming power signal is always amplitude modulated.", "However, that may not be a valid assumption.", "Accordingly, there is a need for a reliable, low-cost and easily integratable solution for detecting information being sent from the receiver to the transmitter in a wireless power system.", "SUMMARY [0008] It is a general object of the invention to provide for recovery of data or commands in a signal stream in a wireless power transmitter.", "[0009] In an aspect, in a primary side wireless power transmitter for being inductively coupled to a secondary side wireless power receiver for supplying power to the wireless power receiver to power a load coupled to the wireless power receiver, a primary side control for receiving communications from the secondary side wireless power receiver through the inductive coupling comprises a primary side tank circuit being excited into oscillation by an excitation signal, the tank circuit receiving a signal from the secondary side wireless power receiver.", "A delay circuit generates a fixed delay clock signal from the excitation signal.", "A sample and hold circuit samples a tank circuit voltage utilizing the fixed delayed clock signal.", "A comparator is coupled to an output of the sample and hold circuit for extracting data or commands from the signal stream.", "[0010] In an aspect, a method of operating a primary side wireless transmitter inductively coupled to a secondary side wireless power receiver for supplying power to the wireless power receiver to power a load coupled to the receiver comprises exciting a tank circuit into oscillation utilizing an excitation signal.", "A signal stream is received from the wireless power receiver in a primary side tank circuit.", "A fixed delay clock signal is generated.", "The tank circuit voltage is sampled utilizing the fixed delayed clock in holding the sample value.", "A threshold voltage signal is generated from the signal stream signal.", "Data is extracted from the signal stream utilizing the threshold voltage signal.", "[0011] In an aspect, a wireless power transfer system comprises a transmitter for transmitting electrical energy through a first inductive coil electromagnetically coupled to a second inductive coil and a receiver.", "A circuit in the receiver couples a resistor or capacitor across the second inductive coil to generate data or command signals in the first inductive coil.", "A sample and hold circuit samples a value of signal in the first inductive coil and holds the value, the sample being taken at a fixed delay from the excitation signal for the first coil.", "A comparator coupled to an output of the sample and hold circuit extracts data or commands from a signal stream.", "BRIEF DESCRIPTION OF DRAWINGS [0012] Further aspects of the invention will appear from the appending claims and from the following detailed description given with reference to the appending drawings.", "[0013] FIG. 1 is a diagram of a wireless power system according to the prior art;", "[0014] FIG. 2 is a graph showing the tank waveform in a wireless power system;", "[0015] FIG. 3 is a graph showing the tank waveform in which the two signals in a wireless power system have the same amplitude;", "[0016] FIG. 4 is a block diagram of an embodiment constructed according to the principles of the present disclosure;", "[0017] FIG. 5 shows an alternate embodiment constructed according to the principles of the present disclosure;", "and [0018] FIGS. 6-12 show waveforms for the circuits illustrated in FIGS. 4 and 5 .", "DETAILED DESCRIPTION [0019] In order to have a reliable communication channel, the system must tolerate system parameter variations including variations in the coupling coefficient (K) of between 0.2 and 0.7, and variation in the receiver load from 5 ohms to 1 kilo ohm, transmit and receive coil inductance variation due to shielding, effects of the battery effects of a magnet used to center the receiving device on the transmitting pad and manufacturing tolerances over the entire range of operating frequency from 110 kHz to 205 kHz.", "[0020] The WPC defined communication channel assumes that the incoming signal is always amplitude modulated.", "However, the present inventors have discovered that this information may be lost because of its low value (i.e. 200 mV) which may be further reduced when the power signal level (which can be 70 Vpp) is divided down to a voltage level that can be handled by an integrated circuit, as this signal, which rides on the power signal, will also be reduced.", "This low level signal can be masked by changes in the load current.", "Accordingly, the inventors have determined that the signal data may lie within the phase of incoming carrier signal, rather than the amplitude.", "Therefore, a traditional amplitude demodulator channel is inadequate to solve the problems described above.", "[0021] FIG. 2 shows the tank signal waveform of the power transmitter where data is being sent from the receiver to the transmitter, generally as 200 .", "In FIG. 2 , the load resistance is 100 ohms, the coefficient of coupling K is 0.7, the secondary (receiver) side capacitor, utilized to transmit data or commands back to the transmitter (primary) side, is 22 nF.", "The primary side inductance is 9.36 μH and the secondary side inductance is 16 μH with the circuit having an operating frequency of 155 kHz.", "Waveform 202 is without the capacitor being coupled across the secondary side of receiver coil and the waveform 204 shows the same signal with the capacitor coupled across the secondary side receive coil to transmit information.", "Under these circumstances, there is a difference in amplitude between the two waveforms and the information in the signal can be amplitude detected.", "[0022] FIG. 3 shows the tank signal waveform of a power transmitter generally as 300 .", "In FIG. 3 , the load resistance is 5 ohms, the coupling coefficient is 0.2, the capacitance is 22 nF, the primary side inductor is 9.36 μH, the secondary side inductor is 16 μH and the operating frequency is 155 kHz.", "As can be seen, the peaks of the waveforms with and without capacitance being switched in at the secondary side, are identical at 306 .", "The exploded view shows the signal 302 which is the signal without the capacitor being switched in across the receiver side coil and the signal 304 which shows the capacitor switched in across the coil.", "Therefore, it may be very difficult to detect the data when the signal peaks are essentially identical utilizing amplitude demodulation.", "[0023] FIG. 4 shows an embodiment of a solution to this problem generally as 400 .", "In FIG. 4 , the tank waveform from the transmitter side tank circuit is coupled via resistor divider 402 , 404 to a capacitor 406 .", "The resistor divider 402 , 404 divides of the voltage across the tank circuit, which may be as much as 70 V peak to peak, to a voltage level that can be handled by an integrated circuit.", "Capacitor 406 blocks the DC level of the input waveform from affecting the setpoint of a buffer circuit 412 , the non-inverting input of which is coupled to the capacitor 406 .", "This allows the setpoint of the buffer 412 to be set via the resistor divider 408 , 410 between a reference voltage and ground.", "The inventors have found it to be advantageous to utilize the voltage just slightly above 0 V, for example, 100 or 200 mV as the setpoint for the buffer 412 .", "In addition, the circuit may be operated at a higher voltage than may be used for other portions of the transmitter circuit, for example 4 V rather than 3.3 V. The combination of these two features allows for an increased voltage swing of the measured data or commands in the signal stream.", "Buffer 412 has its output coupled to the inverting input thereof so that it has a gain of unity.", "The output of buffer 412 is coupled to a sample and hold circuit having a switch 414 which stores the value of the tank waveform, after having been buffered by buffer 412 , and stored in capacitor 416 .", "The switch 414 in the sample and hold circuit is controlled by the output of the 300 ns pulse generator 430 having a fixed phase delay of 60°.", "This circuit 430 is driven, in turn, by the excitation signal 426 used to excite the tank circuit in the transmitter via buffer inverter 428 .", "Therefore, the sample of the tank waveform is taken at fixed phase delay of 60° from the excitation signal for the tank waveform.", "The sample value is stored in capacitor 416 which is coupled between the switch and ground.", "Voltage across capacitor 416 is filtered by a low pass filter 418 , here in a fifth order Butterworth low pass filter.", "The output of the low pass filter 418 is coupled to the inverting input of an auto zero or low offset comparator 424 .", "The output of the low pass filter 418 is also coupled through RC filter 420 , 422 to the non-inverting input of auto zero comparator 424 .", "The resistor 420 is coupled in series between the output of the low pass filter 418 and the non-inverting input of auto zero comparator 424 .", "The capacitor is connected between the non-inverting input of the auto zero comparator 424 and ground.", "The output of auto zero comparator 424 is the data or command signal.", "It should be noted that the fixed phase delay can range at least between 15° and 75° without departing from the principles of the present disclosure.", "[0024] In operation, the coil voltage from the transmit coil in the transmit tank circuit can be sensed directly.", "This voltage, which can be as high as 70 V peak to peak the varying DC level, is AC coupled to the demodulator signal chain through a resistor divider 402 , 404 which reduces the voltage to level it can be handled by an integrated circuit.", "Depending upon the voltage reduction of the resistor divider 402 , 404 , the signal to be detected can be 100 mV or lower riding on top of the 10-70 V peak to peak carrier amplitude.", "Thus it has a very low signal-to-noise ratio (SNR).", "In addition, the carrier has both positive and negative swings with respect to ground.", "Therefore, the present invention maximizes the signal amplitude by setting the DC setpoint at the input of amplifier 412 very close to ground, for example 200 mV.", "This, along with a higher voltage (for example for 4 V) supply for the amplifier 412 allows for a signal swing of almost 4 V. [0025] The input voltage to the non-inverting terminal of buffer amplifier 412 is shown in FIG. 6 , generally as 600 .", "[0026] As can be seen, it is an amplitude (or phase) modulated sine wave of frequency between 110 kHz-205 kHz.", "The amplitude modulation frequency is 2 kHz.", "The 600 shows two periods;", "one just before the modulation and one after the modulation.", "[0027] The output of buffer amplifier 412 is shown in FIG. 7 as a half wave rectified sine wave 700 .", "FIG. 8 shows the square wave excitation signal 800 is used to excite the tank circuit in the transmitter side of the power transmission device.", "This signal is sometimes referred to as a “PWM”", "signal although it is normally a square wave having a 50% duty cycle.", "However, under extreme light load conditions, the cycle would be cut back from the 50% level to 10% level in order to reduce the power generated when the need for power at the receiver side is low.", "FIG. 9 shows the output pulse from the 300 ns pulse generator having a fixed phase delay of 60° generally as 900 .", "Pulse 900 is coupled to the switch 414 of the sample and hold circuit and used to operate the switch to take samples of the output of buffer 412 .", "The samples are held in capacitor 416 .", "[0028] The sampled voltage is shown in FIG. 10 generally as 1000 .", "In order to remove high-frequency noise from the signal, it is passed through a low pass filter, here a fifth order Butterworth low pass filter 418 .", "The output of the Butterworth low pass filter is shown in FIG. 11 generally as 1100 .", "In order to determine the threshold utilized to extract data or commands from signal stream, an RC filter comprising resistor 420 coupled in series between the output of the fifth order Butterworth low pass filter and the non-inverting input of auto zero comparator 424 and a capacitor 422 coupled from the non-inverting input of amplifier 424 to ground is utilized.", "The threshold 1102 generated by the low pass filter 420 , 422 is utilized to extract the data which appears at the output of the auto zero comparator 424 .", "The signal 1106 represents a digital zero and the signal 1104 represents a digital one.", "The signal 1200 is the output of auto-zero comparator 424 , with a digital one output being shown at 1202 .", "[0029] FIG. 5 shows an alternative embodiment of a solution to this problem generally as 500 .", "In FIG. 5 , the tank waveform from the transmitter side tank circuit is coupled via resistor divider 502 , 504 to a capacitor 506 .", "The resistor divider 502 , 504 divides the voltage across the tank circuit, which may be as much as 70 V peak to peak, to a level that can be handled by an integrated circuit.", "Capacitor 506 blocks the DC level of the input waveform from affecting the setpoint of a buffer circuit 512 , the non-inverting input of which is coupled to the capacitor 506 .", "This allows the setpoint of the buffer 512 to be set via the resistor divider 508 , 510 between a reference voltage and ground.", "The inventors have found it to be advantageous to utilize the voltage just slightly above 0 V, for example, 100 or 200 mV as the setpoint for the buffer 512 .", "In addition, this circuit is operated at a higher voltage than may be used for other portions of the transmitter circuit, for example 4 V rather than 3.3 V. The combination of these two features allows for an increased voltage swing of the measured data or commands in the signal stream.", "Buffer 512 has its output coupled to the inverting input thereof so that it has a gain of unity.", "The output of buffer 512 is coupled to a switch of sample and hold circuit 514 .", "The sample and hold circuit 514 is operated by a pulse from pulse generator 530 at a fixed time delay, here shows 1.2 μs.", "Other time delays can be utilize such as 250 ns to 1.2 μs.", "Pulse generator 530 is operated by the excitation signal for the tank circuit 526 passing through buffer inverter 528 .", "This signal is sometimes referred to as a “PWM”", "signal although it is normally a square wave having a 50% duty cycle.", "However, under extreme light load conditions, the cycle would be cut back from the 50% level to the 10% level in order to reduce the power generated when the need for power at the receiver side is low.", "A sample value is stored in capacitor 516 which is coupled between the switch and ground.", "[0030] The voltage across capacitor 516 is filtered by a low pass filter 518 .", "In this embodiment a fifth order Butterworth low pass filter is utilized.", "The output of the Butterworth low pass filter is shown in FIG. 11 generally as 1100 .", "In order to determine the threshold utilized to extract data or commands from signal stream, an RC filter comprising resistor 520 coupled in series between the output of the fifth order Butterworth low pass filter and the non-inverting input of auto zero comparator 524 and a capacitor 522 coupled from the non-inverting input of amplifier 524 to ground is utilized.", "The threshold 1102 generated by the low pass filter 520 , 522 is utilized to extract the data which appears that the output of the auto-zero comparator 524 .", "The signal 1106 represents a digital zero and the signal 1104 represents a digital one.", "The signal 1200 is the output of auto-zero comparator 524 , with a digital one output being shown at 1202 .", "[0031] The fixed time delay could be 250 ns to 1.2 μs, for example.", "The pulse generated by the time delay circuits may be 300 ns wide, for example.", "These circuits are somewhat simpler in construction than a phase delayed pulse generator circuit.", "Circuits capable of generating such time delayed pulses are well known in the art and need not be discussed further herein.", "A circuit for the generation of the phase delayed signals can be found in commonly-own application (TI-74615) filed on even date and incorporated herein by reference in its entirety for all purposes.", "Details on an alternate threshold detection circuit to replace the RC circuit 420 , 422 or 520 , 522 can be found in commonly-owned applications (TI 73620 or TI-74615) filed on even date and incorporated herein by reference in their entirety for all purposes.", "[0032] Although the invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made thereto without departing from the spirit and scope of the invention as defined by the appended claims." ]
This application is a continuation-in-part of application Ser. No. 960,987, filed Nov. 15, 1978 which is now U.S. Pat. No. 4,231,783, issued Nov. 4, 1980. This invention relates to a process for preparing certain substituted 2-imino-4-dihalomethylene-1,3-dithiolane derivatives which have been found to be useful in compositions and methods for reducing herbicidal injury to crop plants. More specifically, the invention relates to a process for preparing the novel 1,3-dithiolane derivatives via photochemical cyclization of certain 2,3,3-trihaloalkyl N-substituted dithiocarbamates, which comprises mixing the dithiocarbamate starting material with a suitable solvent and thereafter exposing the mixture to an ultraviolet light source to effect photo-cyclization of the starting material to produce the 2-imino-4-dihalomethylene-1,3-dithiolane compounds described below. BACKGROUND OF THE INVENTION Herbicides are widely used to control weed growth in growing crop plants. Unchecked weed growth is detrimental to the crop plant because weeds compete with crop plants for light, water and various nutrients often resulting in lower crop yields as well as poorer crop quality. Compositions which protect the crop plant from the action of the herbicide, without reducing the herbicidal effectiveness against the weed to be controlled, are very beneficial. Compounds which are useful in reducing or eliminating crop injury are variously referred to by those skilled in the art as antidotes, safeners or antagonistic agents. The substituted 2-imino-4-dihalomethylene-1,3-dithiolane derivatives described herein are useful as herbicidal safening agents as taught in U.S. Pat. No. 4,231,783, issued to the inventor herein. Certain other 1,3-dithiolane derivatives, their use and processes for their preparation are known in the art; the following patents are representative of the art in this area. U.S. Pat. No. 3,449,365 discloses 2-imino-4-alkalidene-1,3-dithiolanes and teaches that said compounds are useful as insecticides, acaricides and nematocides. U.S. Pat. No. 3,389,148 discloses processes for preparing substituted 1,3-dithioles,1,3-dithianes, and 1,3-dithiolanes and the salts thereof which are intermediates in the preparation of phosphorylated imino compounds. U.S. Pat. No. 3,189,429 and 3,139,439 disclose the preparation and herbicidal use of the halide salts of 2-dialkylamino-1,3-dithiolane derivatives. None of the above patents however teach the substituted 2-imino-4-dihalomethylene-1,3-dithiolane compounds described herein or their preparation via the photochemical cyclization process of the present invention. DESCRIPTION OF THE INVENTION The invention relates to a process for preparing compounds of the formula ##STR1## wherein X is chloro or bromo; R is hydrogen, C 1-5 alkyl or ##STR2## R' is hydrogen or C 1-5 alkyl; X' and Y independently equal hydrogen, C 1-5 alkyl, C 1-5 alkoxy, chloro, bromo, fluoro or iodo; n is 1, 2 or 3; m is 0 or 1; R" is hydrogen or C 1-5 alkyl; which comprises the steps of: (a) dissolving a compound having the formula ##STR3## (wherein X, R and R" are defined as in Formula I above) in a suitable solvent; (b) exposing the mixture to an ultraviolet light source for a time sufficient to effect cyclization of the compound of Formula II to produce the compound of Formula I wherein m is equal to one; and (c) thereafter adding a quantity of base sufficient to neutralize the acid salt to produce the compound of Formula I wherein m is zero. As used herein the term "alkyl" includes those members including straight and branched chain, having from 1 to 5 carbon atoms inclusive, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, isopentyl and the like. The term "alkoxy" includes straight and branched chain members having from 1 to 5 carbon atoms, inclusive, for example, methoxy, ethoxy, isopropoxy and the like. In Formula I wherein m is equal to 1, the compound exists as a salt of a hydrohalic acid, for example, hydrochloric acid or hydrobromic acid. The preferred salt is that derived from hydrochloric acid. The preferred compounds of Formula I, are those wherein X is equal to chlorine and R" is equal hydrogen or methyl. It will be recognized that the hydrohalic salt of the compounds of Formula I is readily neutralized to form the free base by the addition of a sufficient neutralizing amount of organic or inorganic base. Contemplated for use herein are, for example, sodium hydroxide, potassium hydroxide, lithium bicarbonate, sodium bicarbonate, triethyl amine, sodium acetate and the like. Choice of a suitable base is not critical and is within the skill of the art. In accordance with the process of this invention the dithiocarbamate derivative of Formula II is dissolved in a "suitable solvent". The term "suitable solvent" refers to an organic solvent which is non-reactive with said dithiocarbamate intermediate compound and in which the intermediate dithiocarbamate derivative is soluble. Suitable solvents which may be mentioned are carbon tetrachloride, chloroform, toluene, benzene, xylene, methylene chloride and the like. Any ultraviolet light source operated from about 350 to about 550 watts is suitable for use in the present invention. The ultraviolet light source which may be mentioned as suitable for use herein is a 450 watt Hanovia high pressure, quartz, mercury-vapor lamp with a PYREX® filter which absorbs ultraviolet light in the wave length range of from about 270 to about 370 millimicrons. Various types of photochemical equipment are known to those skilled in the art and may be readily purchased from, for example, Ace Glass Inc., 1430 Northwest Boulevard, P.O. Box 688, Vineland, New Jersey 08360. The process of the present invention may be carried out at temperatures ranging from about 10° C. to 50° C. and at atmospheric pressure. The process of the present invention is preferentially carried out at room temperature. The process of the present invention may be illustrated as: ##STR4## The appropriate 2,3,3-trihaloalkyl N-substituted dithiocarbamate dissolved in a suitable solvent, e.g., carbon tetrachloride, chloroform, toluene or the like is placed in a photochemical reaction vessel and sparged with nitrogen. The resulting mixture is thereafter exposed to an ultraviolet light source supplying ultraviolet radiation in the wave length range of from about 270 to about 370 millimicrons for a period of time to complete cyclization, usually about 30 minutes to about 4 hours. The nirogen sparge is continued throughout the reaction. The 2,2,3-trihaloalkyl N-substituted dithiocarbamate compounds used as intermediates starting materials in the process of the present invention may be prepared by reacting approximately equimolar portions of an appropriate substituted amine with carbon disulfide and thereafter adding to this mixture, with gentle heating, a tetrahalopropene compound. Example 1 below describes in detail the preparation of 2,3,3-trichloroalkyl-N-(α-methylbenzyl)dithiocarbamate, a typical intermediate compound. To facilitate further understanding of the process of the present invention, the following illustrative examples are presented. These examples are not intended to be taken as limitative of the invention. EXAMPLE 1 2,3,3-Trichloroallyl N-(α-methylbenzyl)dithio carbamate A two-phase mixture containing 6.0 g (0.0495 mol) dl-α-methylbenzylamine and 8.0 g (0.05 mol) 25% NaOH in 50 ml water was stirred rapidly at 0°-10° C. while 4.0 g (0.05 mol) carbon disulfide was added dropwise over 2-3 minutes. The mixture was stirred and allowed to warm to 20° C. over a one hour period. To this stirred slurry was added 9.0 g (0.05 mol) 1,1,2,3-tetrachloropropene in one portion. A yellow two phase mixture resulted and the temperature slowly rose to a maximum of 28° C. The mixture was heated gently to 45°-50° C. for three hours, then let cool and extracted with 300 ml ethyl ether. The ether solution was washed with two, 50 ml portions of water, treated with activated charcoal and MgSO 4 , filtered through Hy-flo and evaporated in vacuo below 40°/<1 torr to give 14.9 g (88%) of a light orange oil. Anal. Calc'd for C 12 H 12 Cl 3 NS 2 : N, 4.11; Cl, 31.2; S, 18.8; Found: N, 4.26; Cl, 31.4; S, 18.8. EXAMPLE 2 Benzylamine, N-[4-(dichloromethylene)-1,3-dithiolan-2-ylidene] Hydrochloride A solution containing 16.35 g (0.05 mol) of 2,3,3-trichloroallyl N-benzyldithiocarbamate in 50 ml of carbon tetrachloride was placed in a photochemical reaction vessel fitted with a fritted disc bottom for sparging N 2 through the solution. A 450-watt, Hanovia high pressure mercury lamp, with a Pyrex filter, was inserted into the water-cooled quartz immersion well. The solution was agitated with a gentle stream of N 2 bubbles and photolyzed for 35 minutes. The CCl 4 was decanted off leaving a solid which was triturated with benzene, collected by filtration and air dried to give 7.2 g mp 158°-161° C. A sample was recrystallized from CHCl 3 /CCl 4 to give off-white crystals, mp 152°-159° C., yield 44%. Anal. Calc'd for C 11 H 9 Cl 2 NS 2 .HCl: N, 4.29; Cl, 32.6; S, 19.6; N.E., 327; Found: N, 4.32; Cl, 32.4; S, 19.8; N.E., 321. EXAMPLE 3 Benzylamine-,α-methyl-N-[(4-(dichloromethylene)-1,3-dithiolan-2-ylidene] Hydrochloride This compound was prepared according to the procedure described in Example 2 except that 2,3,3-trichloroallyl-N-α-methylbenzyl dithiocarbamate was used. A solid was obtained in 47.5% yield, mp 152°-153° C. Anal. Calc'd for C 12 H 11 Cl 2 NS 2 .HCl: N, 4.11; Cl, 31.2; S, 18.8; Found: N, 4.06; Cl, 31.3; S, 19.0. EXAMPLE 4 Benzylamine-,α-methyl-N-[4-(dichloromethylene)-1,3-dithiolan-2-ylidene] A slurry consisting of 4.8 g (0.014 mol) of the hydrochloride salt of Example 3, in 60 ml of water was stirred and made slightly basic with triethylamine. The mixture was extracted with 50 ml ethyl ether. The separated ether solution was washed with 2, 25 ml portions of cold water, dried over MgSO 4 and evaporated in vacuo at 50°/<0.5 torr to give 4.1 g light amber oil. The oil which solidified on standing at room temperature was recrystallized from pet ether, mp 39°-40.5° C., yield 99%. Anal. Calc'd for C 12 H 11 Cl 2 NS 2 : N, 4.60; Cl, 23.3; S, 21.1; Found: N, 4.71; Cl, 23.3; S, 21.1. EXAMPLE 5 Benzylamine,α-isopropyl N-[4-dichloromethylene) 1,3-dithiolan-2-ylidene] A solution of 35.6 g (0.097 mol) 2,3,3-trichloroallyl N-(α-isopropyl)benzyldithiocarbamate in 100 ml chloroform was photolyzed for 21/2-3 hours. After evaporation of the chloroform the residue was treated with benzene but no crystalline hydrochloride salt formed. The benzene solution was diluted with ethyl ether and the organic solution treated with dilute NaOH. The organic layer was then dried and evaporated to give 29.3 g red amber oil. A 10 g portion of this oil was purified by HPLC (High performance liquid chromatography) on silica gel using toluene to give 5.0 g of the pure free base, yield 45.7%. Anal. Calc'd for C 14 H 15 Cl 2 NS 2 : N, 4.21; Cl, 21.3; S, 19.3; Found: N, 4.16; Cl, 21.4; S, 19.4. EXAMPLE 6 Isopropylamine, N-[4-(dichloromethylene) 1,3-dithiolan-2-ylidene] Hydrochloride A solution containing 10.0 g (0.036 mol) 2,3,3-trichloroallyl N-isopropyldithiocarbamate in 100 ml CCl 4 was photolyzed for 0.5 hour. The solid product was collected by filtration and air dried to give 3.8 g, mp 149°-154° C. Crystallization from CHCl 3 /CCl 4 gave 2.5 g, mp 155°-157° C., yield 38%. Anal. Calc'd for C 7 H 9 Cl 2 NS 2 .HCl: N, 5.03; Cl, 38.2; S, 23.0; Found: N, 5.05; Cl, 37.8; S, 22.8. EXAMPLE 7 1,3-Dithiolane-,2-imino-4-dichloromethylene Hydrochloride A solution containing 4.8 g (0.02 mol) 2,3,3-trichloroallyl dithiocarbamate in 75 mls of chloroform was photolyzed for one hour. The chloroform was drawn off through the bottom sintered glass frit and the solid residue triturated with fresh chloroform again filtered and the recovered solids air dried to give 3.3 g, mp 180° C. (dec.) sinters at 120° C. Crystallization from MeOH/ethyl ether gave a light tan powder, mp 187° C. (dec.). Anal. Calc'd for C 4 H 3 Cl 2 NS 2 .HCl: N, 5.92; Cl, 45.0; S, 27.1; Found: N, 5.94; Cl, 44.2; S, 26.7. Following the procedures described in Examples 2-7, other N-(4-dichloromethylene)-1,3-dithiolanes of the invention were prepared. Table I describes these compounds in greater detail. TABLE I__________________________________________________________________________ ##STR5##Example AnalysisNo. Empirical R Calc'd Found Solvent Mp °C. % Yield__________________________________________________________________________ 8 C.sub.5 H.sub.5 Cl.sub.2 NS.sub.2 . HCl CH.sub.3 N, 5.59; 5.56 CCl.sub.4 193-194 46 Cl, 42.4; 42.6 S, 25.6; 25.7 9 C.sub.12 H.sub.10 Cl.sub.3 NS.sub.2 . HCl ##STR6## N, Cl, S, 3.73; 37.8; 17.1, 3.78 37.7 17.1 CCl.sub.4 144-149 28.510 C.sub.13 H.sub.13 Cl.sub.2 NS.sub.2 . HCl ##STR7## N, Cl, S, 3.95; 30.0; 18.1; 3.89 30.0 18.1 CHCl.sub.3 152.5-155.0 4311 C.sub.16 H.sub.19 Cl.sub.2 NOS.sub.2 . HCl ##STR8## N, Cl, S, 3.39; 25.8; 15.5; 3.36 25.8 15.5 CHCl.sub.3 147-152.5 29.512 C.sub.13 H.sub.13 Cl.sub.2 NS.sub.2 ##STR9## N, Cl, S, 4.40; 22.3; 20.1; 4.43 22.4 20.1 CHCl.sub.3 Oil 94 13* C.sub.16 H.sub.19 Cl.sub.2 NS.sub.2 ##STR10## N, Cl, S, 3.89; 19.7; 17.8; 3.80 19.6 17.7 CHCl.sub.3 Oil 62__________________________________________________________________________ *Isolated by HPLC. Although this invention has been described with respect to specific modifications, the details thereof are not to be construed as limitations, for it will be apparent that various equivalents, changes and modifications may be resorted to without departing from the spirit and scope thereof and it is understood that such equivalent embodiments are intended to be included herein.
2-Imino-4-dichloromethylene-1,3-dithiolane and its derivatives may be prepared by cyclizing, via photolysis, an appropriate 2,3,3-trihaloalkyl N-substituted dithiocarbamate in the presence of a suitable solvent, as for example, carbon tetrachloride. The 1,3-dithiolane derivatives are useful as herbicidal antidotes.
Briefly describe the main idea outlined in the provided context.
[ "This application is a continuation-in-part of application Ser.", "No. 960,987, filed Nov. 15, 1978 which is now U.S. Pat. No. 4,231,783, issued Nov. 4, 1980.", "This invention relates to a process for preparing certain substituted 2-imino-4-dihalomethylene-1,3-dithiolane derivatives which have been found to be useful in compositions and methods for reducing herbicidal injury to crop plants.", "More specifically, the invention relates to a process for preparing the novel 1,3-dithiolane derivatives via photochemical cyclization of certain 2,3,3-trihaloalkyl N-substituted dithiocarbamates, which comprises mixing the dithiocarbamate starting material with a suitable solvent and thereafter exposing the mixture to an ultraviolet light source to effect photo-cyclization of the starting material to produce the 2-imino-4-dihalomethylene-1,3-dithiolane compounds described below.", "BACKGROUND OF THE INVENTION Herbicides are widely used to control weed growth in growing crop plants.", "Unchecked weed growth is detrimental to the crop plant because weeds compete with crop plants for light, water and various nutrients often resulting in lower crop yields as well as poorer crop quality.", "Compositions which protect the crop plant from the action of the herbicide, without reducing the herbicidal effectiveness against the weed to be controlled, are very beneficial.", "Compounds which are useful in reducing or eliminating crop injury are variously referred to by those skilled in the art as antidotes, safeners or antagonistic agents.", "The substituted 2-imino-4-dihalomethylene-1,3-dithiolane derivatives described herein are useful as herbicidal safening agents as taught in U.S. Pat. No. 4,231,783, issued to the inventor herein.", "Certain other 1,3-dithiolane derivatives, their use and processes for their preparation are known in the art;", "the following patents are representative of the art in this area.", "U.S. Pat. No. 3,449,365 discloses 2-imino-4-alkalidene-1,3-dithiolanes and teaches that said compounds are useful as insecticides, acaricides and nematocides.", "U.S. Pat. No. 3,389,148 discloses processes for preparing substituted 1,3-dithioles,1,3-dithianes, and 1,3-dithiolanes and the salts thereof which are intermediates in the preparation of phosphorylated imino compounds.", "U.S. Pat. No. 3,189,429 and 3,139,439 disclose the preparation and herbicidal use of the halide salts of 2-dialkylamino-1,3-dithiolane derivatives.", "None of the above patents however teach the substituted 2-imino-4-dihalomethylene-1,3-dithiolane compounds described herein or their preparation via the photochemical cyclization process of the present invention.", "DESCRIPTION OF THE INVENTION The invention relates to a process for preparing compounds of the formula ##STR1## wherein X is chloro or bromo;", "R is hydrogen, C 1-5 alkyl or ##STR2## R'", "is hydrogen or C 1-5 alkyl;", "X'", "and Y independently equal hydrogen, C 1-5 alkyl, C 1-5 alkoxy, chloro, bromo, fluoro or iodo;", "n is 1, 2 or 3;", "m is 0 or 1;", "R"", "is hydrogen or C 1-5 alkyl;", "which comprises the steps of: (a) dissolving a compound having the formula ##STR3## (wherein X, R and R"", "are defined as in Formula I above) in a suitable solvent;", "(b) exposing the mixture to an ultraviolet light source for a time sufficient to effect cyclization of the compound of Formula II to produce the compound of Formula I wherein m is equal to one;", "and (c) thereafter adding a quantity of base sufficient to neutralize the acid salt to produce the compound of Formula I wherein m is zero.", "As used herein the term "alkyl"", "includes those members including straight and branched chain, having from 1 to 5 carbon atoms inclusive, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, isopentyl and the like.", "The term "alkoxy"", "includes straight and branched chain members having from 1 to 5 carbon atoms, inclusive, for example, methoxy, ethoxy, isopropoxy and the like.", "In Formula I wherein m is equal to 1, the compound exists as a salt of a hydrohalic acid, for example, hydrochloric acid or hydrobromic acid.", "The preferred salt is that derived from hydrochloric acid.", "The preferred compounds of Formula I, are those wherein X is equal to chlorine and R"", "is equal hydrogen or methyl.", "It will be recognized that the hydrohalic salt of the compounds of Formula I is readily neutralized to form the free base by the addition of a sufficient neutralizing amount of organic or inorganic base.", "Contemplated for use herein are, for example, sodium hydroxide, potassium hydroxide, lithium bicarbonate, sodium bicarbonate, triethyl amine, sodium acetate and the like.", "Choice of a suitable base is not critical and is within the skill of the art.", "In accordance with the process of this invention the dithiocarbamate derivative of Formula II is dissolved in a "suitable solvent".", "The term "suitable solvent"", "refers to an organic solvent which is non-reactive with said dithiocarbamate intermediate compound and in which the intermediate dithiocarbamate derivative is soluble.", "Suitable solvents which may be mentioned are carbon tetrachloride, chloroform, toluene, benzene, xylene, methylene chloride and the like.", "Any ultraviolet light source operated from about 350 to about 550 watts is suitable for use in the present invention.", "The ultraviolet light source which may be mentioned as suitable for use herein is a 450 watt Hanovia high pressure, quartz, mercury-vapor lamp with a PYREX® filter which absorbs ultraviolet light in the wave length range of from about 270 to about 370 millimicrons.", "Various types of photochemical equipment are known to those skilled in the art and may be readily purchased from, for example, Ace Glass Inc., 1430 Northwest Boulevard, P.O. Box 688, Vineland, New Jersey 08360.", "The process of the present invention may be carried out at temperatures ranging from about 10° C. to 50° C. and at atmospheric pressure.", "The process of the present invention is preferentially carried out at room temperature.", "The process of the present invention may be illustrated as: ##STR4## The appropriate 2,3,3-trihaloalkyl N-substituted dithiocarbamate dissolved in a suitable solvent, e.g., carbon tetrachloride, chloroform, toluene or the like is placed in a photochemical reaction vessel and sparged with nitrogen.", "The resulting mixture is thereafter exposed to an ultraviolet light source supplying ultraviolet radiation in the wave length range of from about 270 to about 370 millimicrons for a period of time to complete cyclization, usually about 30 minutes to about 4 hours.", "The nirogen sparge is continued throughout the reaction.", "The 2,2,3-trihaloalkyl N-substituted dithiocarbamate compounds used as intermediates starting materials in the process of the present invention may be prepared by reacting approximately equimolar portions of an appropriate substituted amine with carbon disulfide and thereafter adding to this mixture, with gentle heating, a tetrahalopropene compound.", "Example 1 below describes in detail the preparation of 2,3,3-trichloroalkyl-N-(α-methylbenzyl)dithiocarbamate, a typical intermediate compound.", "To facilitate further understanding of the process of the present invention, the following illustrative examples are presented.", "These examples are not intended to be taken as limitative of the invention.", "EXAMPLE 1 2,3,3-Trichloroallyl N-(α-methylbenzyl)dithio carbamate A two-phase mixture containing 6.0 g (0.0495 mol) dl-α-methylbenzylamine and 8.0 g (0.05 mol) 25% NaOH in 50 ml water was stirred rapidly at 0°-10° C. while 4.0 g (0.05 mol) carbon disulfide was added dropwise over 2-3 minutes.", "The mixture was stirred and allowed to warm to 20° C. over a one hour period.", "To this stirred slurry was added 9.0 g (0.05 mol) 1,1,2,3-tetrachloropropene in one portion.", "A yellow two phase mixture resulted and the temperature slowly rose to a maximum of 28° C. The mixture was heated gently to 45°-50° C. for three hours, then let cool and extracted with 300 ml ethyl ether.", "The ether solution was washed with two, 50 ml portions of water, treated with activated charcoal and MgSO 4 , filtered through Hy-flo and evaporated in vacuo below 40°/<1 torr to give 14.9 g (88%) of a light orange oil.", "Anal.", "Calc'd for C 12 H 12 Cl 3 NS 2 : N, 4.11;", "Cl, 31.2;", "S, 18.8;", "Found: N, 4.26;", "Cl, 31.4;", "S, 18.8.", "EXAMPLE 2 Benzylamine, N-[4-(dichloromethylene)-1,3-dithiolan-2-ylidene] Hydrochloride A solution containing 16.35 g (0.05 mol) of 2,3,3-trichloroallyl N-benzyldithiocarbamate in 50 ml of carbon tetrachloride was placed in a photochemical reaction vessel fitted with a fritted disc bottom for sparging N 2 through the solution.", "A 450-watt, Hanovia high pressure mercury lamp, with a Pyrex filter, was inserted into the water-cooled quartz immersion well.", "The solution was agitated with a gentle stream of N 2 bubbles and photolyzed for 35 minutes.", "The CCl 4 was decanted off leaving a solid which was triturated with benzene, collected by filtration and air dried to give 7.2 g mp 158°-161° C. A sample was recrystallized from CHCl 3 /CCl 4 to give off-white crystals, mp 152°-159° C., yield 44%.", "Anal.", "Calc'd for C 11 H 9 Cl 2 NS 2 .", "HCl: N, 4.29;", "Cl, 32.6;", "S, 19.6;", "N.E., 327;", "Found: N, 4.32;", "Cl, 32.4;", "S, 19.8;", "N.E., 321.", "EXAMPLE 3 Benzylamine-,α-methyl-N-[(4-(dichloromethylene)-1,3-dithiolan-2-ylidene] Hydrochloride This compound was prepared according to the procedure described in Example 2 except that 2,3,3-trichloroallyl-N-α-methylbenzyl dithiocarbamate was used.", "A solid was obtained in 47.5% yield, mp 152°-153° C. Anal.", "Calc'd for C 12 H 11 Cl 2 NS 2 .", "HCl: N, 4.11;", "Cl, 31.2;", "S, 18.8;", "Found: N, 4.06;", "Cl, 31.3;", "S, 19.0.", "EXAMPLE 4 Benzylamine-,α-methyl-N-[4-(dichloromethylene)-1,3-dithiolan-2-ylidene] A slurry consisting of 4.8 g (0.014 mol) of the hydrochloride salt of Example 3, in 60 ml of water was stirred and made slightly basic with triethylamine.", "The mixture was extracted with 50 ml ethyl ether.", "The separated ether solution was washed with 2, 25 ml portions of cold water, dried over MgSO 4 and evaporated in vacuo at 50°/<0.5 torr to give 4.1 g light amber oil.", "The oil which solidified on standing at room temperature was recrystallized from pet ether, mp 39°-40.5° C., yield 99%.", "Anal.", "Calc'd for C 12 H 11 Cl 2 NS 2 : N, 4.60;", "Cl, 23.3;", "S, 21.1;", "Found: N, 4.71;", "Cl, 23.3;", "S, 21.1.", "EXAMPLE 5 Benzylamine,α-isopropyl N-[4-dichloromethylene) 1,3-dithiolan-2-ylidene] A solution of 35.6 g (0.097 mol) 2,3,3-trichloroallyl N-(α-isopropyl)benzyldithiocarbamate in 100 ml chloroform was photolyzed for 21/2-3 hours.", "After evaporation of the chloroform the residue was treated with benzene but no crystalline hydrochloride salt formed.", "The benzene solution was diluted with ethyl ether and the organic solution treated with dilute NaOH.", "The organic layer was then dried and evaporated to give 29.3 g red amber oil.", "A 10 g portion of this oil was purified by HPLC (High performance liquid chromatography) on silica gel using toluene to give 5.0 g of the pure free base, yield 45.7%.", "Anal.", "Calc'd for C 14 H 15 Cl 2 NS 2 : N, 4.21;", "Cl, 21.3;", "S, 19.3;", "Found: N, 4.16;", "Cl, 21.4;", "S, 19.4.", "EXAMPLE 6 Isopropylamine, N-[4-(dichloromethylene) 1,3-dithiolan-2-ylidene] Hydrochloride A solution containing 10.0 g (0.036 mol) 2,3,3-trichloroallyl N-isopropyldithiocarbamate in 100 ml CCl 4 was photolyzed for 0.5 hour.", "The solid product was collected by filtration and air dried to give 3.8 g, mp 149°-154° C. Crystallization from CHCl 3 /CCl 4 gave 2.5 g, mp 155°-157° C., yield 38%.", "Anal.", "Calc'd for C 7 H 9 Cl 2 NS 2 .", "HCl: N, 5.03;", "Cl, 38.2;", "S, 23.0;", "Found: N, 5.05;", "Cl, 37.8;", "S, 22.8.", "EXAMPLE 7 1,3-Dithiolane-,2-imino-4-dichloromethylene Hydrochloride A solution containing 4.8 g (0.02 mol) 2,3,3-trichloroallyl dithiocarbamate in 75 mls of chloroform was photolyzed for one hour.", "The chloroform was drawn off through the bottom sintered glass frit and the solid residue triturated with fresh chloroform again filtered and the recovered solids air dried to give 3.3 g, mp 180° C. (dec.) sinters at 120° C. Crystallization from MeOH/ethyl ether gave a light tan powder, mp 187° C. (dec.).", "Anal.", "Calc'd for C 4 H 3 Cl 2 NS 2 .", "HCl: N, 5.92;", "Cl, 45.0;", "S, 27.1;", "Found: N, 5.94;", "Cl, 44.2;", "S, 26.7.", "Following the procedures described in Examples 2-7, other N-(4-dichloromethylene)-1,3-dithiolanes of the invention were prepared.", "Table I describes these compounds in greater detail.", "TABLE I__________________________________________________________________________ ##STR5##Example AnalysisNo.", "Empirical R Calc'd Found Solvent Mp °C.", "% Yield__________________________________________________________________________ 8 C.sub[.", "].5 H.sub[.", "].5 Cl.", "sub[.", "].2 NS.", "sub[.", "].2 .", "HCl CH.", "sub[.", "].3 N, 5.59;", "5.56 CCl.", "sub[.", "].4 193-194 46 Cl, 42.4;", "42.6 S, 25.6;", "25.7 9 C.sub[.", "].12 H.sub[.", "].10 Cl.", "sub[.", "].3 NS.", "sub[.", "].2 .", "HCl ##STR6## N, Cl, S, 3.73;", "37.8;", "17.1, 3.78 37.7 17.1 CCl.", "sub[.", "].4 144-149 28.510 C.sub[.", "].13 H.sub[.", "].13 Cl.", "sub[.", "].2 NS.", "sub[.", "].2 .", "HCl ##STR7## N, Cl, S, 3.95;", "30.0;", "18.1;", "3.89 30.0 18.1 CHCl.", "sub[.", "].3 152.5-155.0 4311 C.sub[.", "].16 H.sub[.", "].19 Cl.", "sub[.", "].2 NOS.", "sub[.", "].2 .", "HCl ##STR8## N, Cl, S, 3.39;", "25.8;", "15.5;", "3.36 25.8 15.5 CHCl.", "sub[.", "].3 147-152.5 29.512 C.sub[.", "].13 H.sub[.", "].13 Cl.", "sub[.", "].2 NS.", "sub[.", "].2 ##STR9## N, Cl, S, 4.40;", "22.3;", "20.1;", "4.43 22.4 20.1 CHCl.", "sub[.", "].3 Oil 94 13* C.sub[.", "].16 H.sub[.", "].19 Cl.", "sub[.", "].2 NS.", "sub[.", "].2 ##STR10## N, Cl, S, 3.89;", "19.7;", "17.8;", "3.80 19.6 17.7 CHCl.", "sub[.", "].3 Oil 62__________________________________________________________________________ *Isolated by HPLC.", "Although this invention has been described with respect to specific modifications, the details thereof are not to be construed as limitations, for it will be apparent that various equivalents, changes and modifications may be resorted to without departing from the spirit and scope thereof and it is understood that such equivalent embodiments are intended to be included herein." ]
BACKGROUND OF THE INVENTION [0001] I. Field of the Invention [0002] This invention relates generally to a portable, hand-held apparatus for equalizing pressure in the middle ear, and more particularly to a device of the type described that provides improved control over the air pressure applied by the device to a patient's Eustachian tubes during a treatment procedure. [0003] II. Discussion of the Prior Art [0004] In U.S. Pat. Nos. 5,419,762 and 5,885,242 to Arick, et al. (the contents of which are hereby incorporated by reference), there is described an apparatus for facilitating the Politzer maneuver for equalizing the pressure in the middle ear in patients suffering from Eustachian Tube Dysfunction (ETD) or Aerotitis Media. That apparatus comprises an electric-powered air source contained in a hand-held housing for providing a continuous flow of air to an exit port of the device. More particularly, a battery-powered DC motor, when energized, drives a small pump or compressor whose outlet is connected by a short length of plastic tubing contained in the housing to the device's exit port in a nozzle projecting from the housing and that is adapted to seal against one of the patient's nostrils. With the continuous flow of air into one nostril and with the other nostril pinched closed, the patient is asked to swallow. Swallowing closes the esophagus and directs air pressure to the Eustachian tube, opening it to allow any fluid to flow from the middle ear and/or to restore pressure balance to the middle ear. [0005] The Arick, et al. '242 patent suggests that the applied pressure generated by the pump be limited to a lower pressure of about 1.5 psi for infants and small children and a higher pressure of about 3 psi for adults. For this purpose, a speed control circuit is coupled between the battery and the motor terminals. It has been found, however, that attempting to accurately regulate the pressure of the output air by controlling motor pump speed is less than satisfactory. Those skilled in the art recognize that the motor speed, and thus the pump's air flow rate is dependent on battery voltage and that battery voltage varies with the depletion state of the battery's charge as well as with temperature. One can understand, therefore, that the desired airflow rate, measured in liters-per-minute and in air pressure measured in pounds-per-square-inch that can be developed in a given time using the selector switch 20a in FIG. 7 of the '242 patent, may be difficult to maintain. [0006] It is accordingly a principal object of the present invention to provide an improved apparatus for affecting the Politzer maneuver. [0007] Another object of the invention is to provide a hand-held, battery-operated device containing a motor-driven pump for producing a continuous flow of air at the device outlet nozzle at a plurality of selectable pressure values that are independent of battery state over the expected life of the battery. SUMMARY OF THE INVENTION [0008] In its broadest sense, the present invention comprises an apparatus for equalizing pressure in the middle ear of a patient where the apparatus incorporates within a hand-held housing an electric-powered air source for providing a predetermined continuous flow of air to an exit port of the device and that has an adjustable valve assembly operatively coupled between the electrically-powered air source and the exit port for selecting a pressure limit for the air at the exit port. [0009] Without limitation, the adjustable valve assembly may comprise a valve housing having an inlet port in fluid communication with the electrically-powered air source, an outlet port in fluid communication with the device's exit port, an exhaust port leading to the ambient and a valve seat located between the exhaust port and the inlet port. A spring biased ball cooperates with the valve seat to block airflow through the exhaust port so long as the air pressure at the exit port remains below a predetermined level. Means are then provided for varying the spring-biasing force on the ball to adjust the pressure at which the ball unseats. [0010] Alternatively, the adjustable valve assembly may comprise a molded plastic manifold having an inlet port in fluid communication with the electrically-powered air source, an outlet port in fluid communication with the exit port and an exhaust port leading to the ambient where the manifold incorporates a rotatable turret carrying a plurality of check valves, where each of the check valves is adapted to open at different predetermined pressures. Rotation of the turret selectively places a selected one of the plurality of check valves in fluid circuit between the exhaust port and the inlet port. DESCRIPTION OF THE DRAWINGS [0011] The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description of a preferred embodiment, especially when considered in conjunction with the accompanying drawings in which like numerals in the several views refer to corresponding parts. [0012] FIG. 1 is a schematic diagram showing the arrangement of the components used in the present invention; [0013] FIG. 2 is an isometric view of the housing comprising the hand-held device; [0014] FIG. 3 is an exploded view of an adjustable valve assembly usable in the combination of FIG. 1 ; and [0015] FIG. 4 is an alternative design for an adjustable valve assembly usable in implementing the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENT [0016] Referring to the schematic diagram of FIG. 1 , the improved apparatus for equalizing pressure in a patient's middle ear is seen to comprise a battery 10 that is connected through a single pole, single throw switch 12 to a small DC motor 14 of an electrically-powered air source, shown enclosed by the broken line box 16 . The motor shaft 18 drives a compressor pump 20 for continuously producing air, under pressure, to the input of an adjustable valve assembly 22 by way of a tubing connection 24 . The valve 22 has an outlet port 26 connected by tubing 28 to a nose piece 30 . The adjustable valve 22 also has an exhaust port 32 leading to the ambient. [0017] The valve 22 remains closed so long as the inlet air pressure from the compressor 20 is below a preset value. The valve remains closed, blocking the exhaust port while allowing air flow from the inlet 24 through the outlet 26 leading to the nose piece 30 . However, when the pressure at the inlet port of the valve 22 reaches the preset valve, the valve opens, preventing any further increase in the pressure of the air reaching the nose piece 30 . [0018] FIG. 2 is a cross-sectional view showing how the components of FIG. 1 may be placed within a hand-held housing. The housing itself is identified by numeral 34 and is preferably formed from a suitable plastic and it includes a top 36 , a base 38 and four mutually perpendicular sidewalls, only three of which are seen in FIG. 2 including a front wall 40 , a rear wall 42 and a left side wall 44 . The conically-shaped nozzle 30 projects upwardly from the top surface 36 . It may be permanently affixed to the top surface 36 or, preferably is removable and replaceable. The nozzle 30 includes a central 46 leading to an exit port 48 proximate its apex. It has also proved expedient to incorporate a duck-bill valve 49 in the nozzle which opens with air flow from the valve 22 but that serves to block expiratory flow carrying mucous back through the nozzle. [0019] The electrical on/off switch 12 is shown as being located within the housing 34 but with an actuating member 50 projecting through the front wall 40 of the housing so as to be assessable to the user. [0020] The power source (battery) 10 is suitably supported within the housing and provision is made so that the housing can be opened to gain access to the battery 10 for replacement purposes. [0021] Also contained within the housing 34 is the motor-driven compressor 16 that includes a miniature DC motor 14 connected in driving relation to a compressor pump 20 . The motor 14 and pump 20 is preferably an A-Series, Iron-Core Air Pump available from Sensidyne, Inc. capable of delivering from about 0.1 to about 3.5 l/min at a pressure of up to 10 psig. The combination motor and pump occupies only 3.4 cubic in. and weighs approximately 2.9 oz. The pump 20 , itself, is a diaphragm pump. While the Sensidyne Micro Air Pump is well suited to the present application, other commercially available DC motor driven pumps are commercially available from other suppliers and limitation to the Sensidyne A-Series motor-driven pump is not intended. [0022] The adjustable valve assembly 22 is supported by the base 38 of the housing and it has a valve inlet 52 connected by plastic tubing 54 to the outlet of the pump 20 . The valve outlet 56 is connected by flexible plastic tubing 58 to the bore 46 of the nose piece 30 . [0023] For clarity in the drawings, the electrical wires connecting the battery 10 , the switch 12 and the motor 14 in series are not shown. [0024] Referring next to FIG. 3 , there is shown the make-up of one type of pressure adjustable valve that can serve as the valve 22 . It includes a tubular air flow passage 60 leading from the valve inlet 52 to its outlet 56 . The tubular flow passage 60 is integrally molded with a valve housing 62 that includes a central bore 64 leading to a frusto-conically shaped valve seat 66 located between the bore 64 and a counterbore 68 leading to the passage 60 . A transversely extending bore 70 is formed through the wall of the valve housing 62 . [0025] Contained within the bore 64 is a ball valve member 72 that is urged against the seat 66 by a spring 74 . An adjusting nut 76 is internally threaded so as to mate with the external threads on the valve housing 62 . By rotating adjusting nut 76 to the right, the biasing force of the spring 74 on the ball 72 is increased, thus requiring a higher air pressure in the passage 60 to unseat the ball. Turning the adjustment nut 76 to the left when viewed as in FIG. 3 decreases the spring biasing force on the ball 72 , thus lessening the amount of air pressure in the passageway 60 needed to unseat the ball and allow air flow out through the bore 70 . [0026] The adjustable valve assembly 22 is mounted in the housing 34 of FIG. 2 such that the adjustment nut 76 is exposed and assessable to allow its rotation. [0027] Assuming that the pump 20 is capable of delivering air at a pressure of 10 psig and the valve is adjusted such that a pressure of 3 psig will unseat the ball 72 , the excess pressure will then be relieved through the port 70 in the valve housing 62 . If desired, a suitable detent can be placed between the adjusting nut 76 and the valve housing 62 to establish plural predetermined pressure settings for the adjustable valve assembly 22 . Without limitation, the detent may permit selection of, say, 1.5 psi, 2.5 psi, 5 psi and 10 psi. It has been found than the incorporation of the adjustable valve 22 in the hand-held device yields a more precise control of the air pressure at the exit port 48 that is achievable using a speed control circuit for regulating the speed of the motor 14 driving the pump 20 . [0028] FIG. 4 illustrates an alternative construction of an adjustable valve assembly that can be used as a valve 22 in the hand-held device used for equalizing pressure in the middle ear of a patient. It is seen to comprise a molded plastic valve body 78 having a cylindrical cavity for receiving a rotatable turret 80 therein. Integrally molded with the housing member 78 are a plurality of exhaust ports 82 , 84 and 86 . Disposed in each of the exhaust ports is a check valve, each designed to open at a different predetermined pressure. For example, the check valve (not shown) inserted within the exhaust port 82 may be designed to open at 1.5 psi, the check valve contained within the exhaust port 84 to open at 2½ psi and the check valve within the exhaust port 86 designed to open at 5 psi. [0029] Also integrally molded with the housing 78 is a flow passage comprising a tube 88 . The outlet of the pump 20 connects by tubing 54 to the valve inlet 52 . The valve outlet 56 is coupled by tubing 58 to the bore 46 in the nozzle 30 . The turret 80 includes an L-shaped passageway 89 with one leg of the L in fluid communication with the interior of the tube 88 and the other leg of the L exiting the turret 80 at a location that sequentially aligns with the exhaust ports 82 , 84 and 86 as the turret 80 is rotated. [0030] In operation, with the turret set so that the L-shaped passage has its one leg aligned with the exhaust port 82 , it may take a pressure of 1.5 psi to open the check valve in the exhaust port 82 . In a similar manner, when the turret 80 is rotated so that the one leg of the L-shaped bore aligns with the exhaust port 84 , the check valve contained therein will only open when the pressure in tube 88 equals or exceeds 2.5 psi. Assuming that the check valve associated with the exhaust port 86 requires 5 psi to actuate it, a user may select 5 psi as the desired pressure for application through the nose piece 30 by rotating the turret 80 until the one leg of the L-shaped bore formed in the turret aligns with the exhaust port 86 . Again, the adjustable valve assembly of FIG. 4 is disposed in the hand held housing 34 so that the rotatable turret 80 is accessible through the base 38 of the housing 34 . [0031] This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself.
An apparatus for equalizing pressure in a middle ear includes a hand-held air source for providing a continuous flow of air at a predetermined rate and a tapered sealing nostril plug adapted to be sealed against a nostril. The tapered nostril plug has a channel there through for delivering the continuous flow of air. The channel of the tapered plug is adapted to be placed in communication with the air source through an adjustable valve assembly for selecting a pressure limit for the air in the channel of the nostril plug.
Provide a concise summary of the essential information conveyed in the context.
[ "BACKGROUND OF THE INVENTION [0001] I. Field of the Invention [0002] This invention relates generally to a portable, hand-held apparatus for equalizing pressure in the middle ear, and more particularly to a device of the type described that provides improved control over the air pressure applied by the device to a patient's Eustachian tubes during a treatment procedure.", "[0003] II.", "Discussion of the Prior Art [0004] In U.S. Pat. Nos. 5,419,762 and 5,885,242 to Arick, et al.", "(the contents of which are hereby incorporated by reference), there is described an apparatus for facilitating the Politzer maneuver for equalizing the pressure in the middle ear in patients suffering from Eustachian Tube Dysfunction (ETD) or Aerotitis Media.", "That apparatus comprises an electric-powered air source contained in a hand-held housing for providing a continuous flow of air to an exit port of the device.", "More particularly, a battery-powered DC motor, when energized, drives a small pump or compressor whose outlet is connected by a short length of plastic tubing contained in the housing to the device's exit port in a nozzle projecting from the housing and that is adapted to seal against one of the patient's nostrils.", "With the continuous flow of air into one nostril and with the other nostril pinched closed, the patient is asked to swallow.", "Swallowing closes the esophagus and directs air pressure to the Eustachian tube, opening it to allow any fluid to flow from the middle ear and/or to restore pressure balance to the middle ear.", "[0005] The Arick, et al.", "'242 patent suggests that the applied pressure generated by the pump be limited to a lower pressure of about 1.5 psi for infants and small children and a higher pressure of about 3 psi for adults.", "For this purpose, a speed control circuit is coupled between the battery and the motor terminals.", "It has been found, however, that attempting to accurately regulate the pressure of the output air by controlling motor pump speed is less than satisfactory.", "Those skilled in the art recognize that the motor speed, and thus the pump's air flow rate is dependent on battery voltage and that battery voltage varies with the depletion state of the battery's charge as well as with temperature.", "One can understand, therefore, that the desired airflow rate, measured in liters-per-minute and in air pressure measured in pounds-per-square-inch that can be developed in a given time using the selector switch 20a in FIG. 7 of the '242 patent, may be difficult to maintain.", "[0006] It is accordingly a principal object of the present invention to provide an improved apparatus for affecting the Politzer maneuver.", "[0007] Another object of the invention is to provide a hand-held, battery-operated device containing a motor-driven pump for producing a continuous flow of air at the device outlet nozzle at a plurality of selectable pressure values that are independent of battery state over the expected life of the battery.", "SUMMARY OF THE INVENTION [0008] In its broadest sense, the present invention comprises an apparatus for equalizing pressure in the middle ear of a patient where the apparatus incorporates within a hand-held housing an electric-powered air source for providing a predetermined continuous flow of air to an exit port of the device and that has an adjustable valve assembly operatively coupled between the electrically-powered air source and the exit port for selecting a pressure limit for the air at the exit port.", "[0009] Without limitation, the adjustable valve assembly may comprise a valve housing having an inlet port in fluid communication with the electrically-powered air source, an outlet port in fluid communication with the device's exit port, an exhaust port leading to the ambient and a valve seat located between the exhaust port and the inlet port.", "A spring biased ball cooperates with the valve seat to block airflow through the exhaust port so long as the air pressure at the exit port remains below a predetermined level.", "Means are then provided for varying the spring-biasing force on the ball to adjust the pressure at which the ball unseats.", "[0010] Alternatively, the adjustable valve assembly may comprise a molded plastic manifold having an inlet port in fluid communication with the electrically-powered air source, an outlet port in fluid communication with the exit port and an exhaust port leading to the ambient where the manifold incorporates a rotatable turret carrying a plurality of check valves, where each of the check valves is adapted to open at different predetermined pressures.", "Rotation of the turret selectively places a selected one of the plurality of check valves in fluid circuit between the exhaust port and the inlet port.", "DESCRIPTION OF THE DRAWINGS [0011] The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description of a preferred embodiment, especially when considered in conjunction with the accompanying drawings in which like numerals in the several views refer to corresponding parts.", "[0012] FIG. 1 is a schematic diagram showing the arrangement of the components used in the present invention;", "[0013] FIG. 2 is an isometric view of the housing comprising the hand-held device;", "[0014] FIG. 3 is an exploded view of an adjustable valve assembly usable in the combination of FIG. 1 ;", "and [0015] FIG. 4 is an alternative design for an adjustable valve assembly usable in implementing the present invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENT [0016] Referring to the schematic diagram of FIG. 1 , the improved apparatus for equalizing pressure in a patient's middle ear is seen to comprise a battery 10 that is connected through a single pole, single throw switch 12 to a small DC motor 14 of an electrically-powered air source, shown enclosed by the broken line box 16 .", "The motor shaft 18 drives a compressor pump 20 for continuously producing air, under pressure, to the input of an adjustable valve assembly 22 by way of a tubing connection 24 .", "The valve 22 has an outlet port 26 connected by tubing 28 to a nose piece 30 .", "The adjustable valve 22 also has an exhaust port 32 leading to the ambient.", "[0017] The valve 22 remains closed so long as the inlet air pressure from the compressor 20 is below a preset value.", "The valve remains closed, blocking the exhaust port while allowing air flow from the inlet 24 through the outlet 26 leading to the nose piece 30 .", "However, when the pressure at the inlet port of the valve 22 reaches the preset valve, the valve opens, preventing any further increase in the pressure of the air reaching the nose piece 30 .", "[0018] FIG. 2 is a cross-sectional view showing how the components of FIG. 1 may be placed within a hand-held housing.", "The housing itself is identified by numeral 34 and is preferably formed from a suitable plastic and it includes a top 36 , a base 38 and four mutually perpendicular sidewalls, only three of which are seen in FIG. 2 including a front wall 40 , a rear wall 42 and a left side wall 44 .", "The conically-shaped nozzle 30 projects upwardly from the top surface 36 .", "It may be permanently affixed to the top surface 36 or, preferably is removable and replaceable.", "The nozzle 30 includes a central 46 leading to an exit port 48 proximate its apex.", "It has also proved expedient to incorporate a duck-bill valve 49 in the nozzle which opens with air flow from the valve 22 but that serves to block expiratory flow carrying mucous back through the nozzle.", "[0019] The electrical on/off switch 12 is shown as being located within the housing 34 but with an actuating member 50 projecting through the front wall 40 of the housing so as to be assessable to the user.", "[0020] The power source (battery) 10 is suitably supported within the housing and provision is made so that the housing can be opened to gain access to the battery 10 for replacement purposes.", "[0021] Also contained within the housing 34 is the motor-driven compressor 16 that includes a miniature DC motor 14 connected in driving relation to a compressor pump 20 .", "The motor 14 and pump 20 is preferably an A-Series, Iron-Core Air Pump available from Sensidyne, Inc. capable of delivering from about 0.1 to about 3.5 l/min at a pressure of up to 10 psig.", "The combination motor and pump occupies only 3.4 cubic in.", "and weighs approximately 2.9 oz.", "The pump 20 , itself, is a diaphragm pump.", "While the Sensidyne Micro Air Pump is well suited to the present application, other commercially available DC motor driven pumps are commercially available from other suppliers and limitation to the Sensidyne A-Series motor-driven pump is not intended.", "[0022] The adjustable valve assembly 22 is supported by the base 38 of the housing and it has a valve inlet 52 connected by plastic tubing 54 to the outlet of the pump 20 .", "The valve outlet 56 is connected by flexible plastic tubing 58 to the bore 46 of the nose piece 30 .", "[0023] For clarity in the drawings, the electrical wires connecting the battery 10 , the switch 12 and the motor 14 in series are not shown.", "[0024] Referring next to FIG. 3 , there is shown the make-up of one type of pressure adjustable valve that can serve as the valve 22 .", "It includes a tubular air flow passage 60 leading from the valve inlet 52 to its outlet 56 .", "The tubular flow passage 60 is integrally molded with a valve housing 62 that includes a central bore 64 leading to a frusto-conically shaped valve seat 66 located between the bore 64 and a counterbore 68 leading to the passage 60 .", "A transversely extending bore 70 is formed through the wall of the valve housing 62 .", "[0025] Contained within the bore 64 is a ball valve member 72 that is urged against the seat 66 by a spring 74 .", "An adjusting nut 76 is internally threaded so as to mate with the external threads on the valve housing 62 .", "By rotating adjusting nut 76 to the right, the biasing force of the spring 74 on the ball 72 is increased, thus requiring a higher air pressure in the passage 60 to unseat the ball.", "Turning the adjustment nut 76 to the left when viewed as in FIG. 3 decreases the spring biasing force on the ball 72 , thus lessening the amount of air pressure in the passageway 60 needed to unseat the ball and allow air flow out through the bore 70 .", "[0026] The adjustable valve assembly 22 is mounted in the housing 34 of FIG. 2 such that the adjustment nut 76 is exposed and assessable to allow its rotation.", "[0027] Assuming that the pump 20 is capable of delivering air at a pressure of 10 psig and the valve is adjusted such that a pressure of 3 psig will unseat the ball 72 , the excess pressure will then be relieved through the port 70 in the valve housing 62 .", "If desired, a suitable detent can be placed between the adjusting nut 76 and the valve housing 62 to establish plural predetermined pressure settings for the adjustable valve assembly 22 .", "Without limitation, the detent may permit selection of, say, 1.5 psi, 2.5 psi, 5 psi and 10 psi.", "It has been found than the incorporation of the adjustable valve 22 in the hand-held device yields a more precise control of the air pressure at the exit port 48 that is achievable using a speed control circuit for regulating the speed of the motor 14 driving the pump 20 .", "[0028] FIG. 4 illustrates an alternative construction of an adjustable valve assembly that can be used as a valve 22 in the hand-held device used for equalizing pressure in the middle ear of a patient.", "It is seen to comprise a molded plastic valve body 78 having a cylindrical cavity for receiving a rotatable turret 80 therein.", "Integrally molded with the housing member 78 are a plurality of exhaust ports 82 , 84 and 86 .", "Disposed in each of the exhaust ports is a check valve, each designed to open at a different predetermined pressure.", "For example, the check valve (not shown) inserted within the exhaust port 82 may be designed to open at 1.5 psi, the check valve contained within the exhaust port 84 to open at 2½ psi and the check valve within the exhaust port 86 designed to open at 5 psi.", "[0029] Also integrally molded with the housing 78 is a flow passage comprising a tube 88 .", "The outlet of the pump 20 connects by tubing 54 to the valve inlet 52 .", "The valve outlet 56 is coupled by tubing 58 to the bore 46 in the nozzle 30 .", "The turret 80 includes an L-shaped passageway 89 with one leg of the L in fluid communication with the interior of the tube 88 and the other leg of the L exiting the turret 80 at a location that sequentially aligns with the exhaust ports 82 , 84 and 86 as the turret 80 is rotated.", "[0030] In operation, with the turret set so that the L-shaped passage has its one leg aligned with the exhaust port 82 , it may take a pressure of 1.5 psi to open the check valve in the exhaust port 82 .", "In a similar manner, when the turret 80 is rotated so that the one leg of the L-shaped bore aligns with the exhaust port 84 , the check valve contained therein will only open when the pressure in tube 88 equals or exceeds 2.5 psi.", "Assuming that the check valve associated with the exhaust port 86 requires 5 psi to actuate it, a user may select 5 psi as the desired pressure for application through the nose piece 30 by rotating the turret 80 until the one leg of the L-shaped bore formed in the turret aligns with the exhaust port 86 .", "Again, the adjustable valve assembly of FIG. 4 is disposed in the hand held housing 34 so that the rotatable turret 80 is accessible through the base 38 of the housing 34 .", "[0031] This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required.", "However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself." ]
FIELD OF THE INVENTION The invention relates to a valve having at least one pump connection, one tank connection, and one appliance connection and a valve piston positionable inside the valve housing, which piston separates the pump connection from the tank connection in at least one blocked position and which operates in conjunction with an energy accumulator, a self-adjusting fluid flow being controllable by means of a control device between the appliance connection and the tank connection. BACKGROUND OF THE INVENTION Such valves are routinely used in so-called hydraulic load sensing systems or control means and operate there like a piston manometer, directing an unneeded pump feed flow back to the tank. In order to prevent leakages in the appliance circuit from raising the appliance pressure to the performance level of the pump and thereby possibly disabling the load sensing system, the load on the appliance connection to the tank is to be removed. Such load removal is currently effected in a cost-effective manner by use of aperture control means, the aperture preferably being integrated directly into the piston manometer or being used separately in a control unit which is part of the load sensing control mechanism. A disadvantage of these known solutions with the aperture design feature is the pressure dependence of the volume flow draining to the tank. In the case of appliances whose volume flow is independent of load, proceeds by way of proportional valves, for example, this then results in constant slowing of the appliance with increase in the load pressure, something which has an especially negative effect in the case of appliances with a low volume flow. SUMMARY OF THE INVENTION On the basis of this state of the art the invention pursues the object of further improving known valves to the end that such valves will not be characterized by the disadvantages described, especially when employed in so-called load sensing systems. In addition, it is to be possible to reduce the valve cost efficiently and so that the valve occupies little space. The object as thus formulated is attained by means of a valve having the features specified in claim 1 . Since, as specified in the descriptive portion of claim 1 , the control device consists of a fluid flow controller integrated into the valve piston it is possible, in contrast with known valve solutions, to use the aperture design to reduce the volume flow to the appliance, independently of the load, by a constant value, so that proportional load-independent control is effected. The disadvantages of the state of the art as described, in the form of slowing of the appliance in particular, are thus reliably excluded. The solution with the fluid flow controller claimed for the invention can be cost effectively applied and space-saving installation in the valve itself is possible as a result of integration of the fluid flow controller into the valve box. Since the valve claimed for the invention has only a few structural components, reliability of operation is ensured which benefits the load sensing system as a whole. Other advantageous embodiments are specified in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS The valve claimed for the invention is explained in detail in what follows with reference to the drawing, in which, in diagrammatic form and not to scale, FIG. 1 presents a longitudinal section through the valve claimed for the invention; FIG. 2 in the form of a circuit diagram, illustrates use of the valve as shown in FIG. 1 in the case of a load sensing system with an operating cylinder as hydraulic appliance. DETAILED DESCRIPTION OF THE INVENTION The valve shown in longitudinal section in FIG. 1 has a pump connection 10 , specifically on the front end of a valve box 12 , designed as a screw-in cartridge to be secured in control units or the like for subsequent use. Configuration as a built-in set or the like is also possible. The valve box 12 has at its end facing the pump connection 10 two first tank connections 14 diametrically opposite each other. As viewed in the line of sight to FIG. 1, mounted above them (as shown in the left half of the illustration) is another separate tank connection 16 whose free open cross-section is smaller than the corresponding diameter area of the first tank connections 14 . On the other hand, another cross bore which serves as appliance connection 18 has been introduced into the valve box 12 . The tank connections 14 and 16 also are in the form of cross bores in the valve box 12 . The connections 14 , 16 , and 18 in question extend more or less transversely to the longitudinal axis 20 of the valve box 12 . The pump connection 10 , in contrast, is mounted along the longitudinal axis 20 of the valve box 12 , on the front side of the latter. Mounted in the valve box 12 so as to be longitudinally positionable is a valve piston 22 the external circumference of which is provided with pressure relief ducts by conventional means, which accordingly are not described in detail. In one of its blocked positions as shown in FIG. 1 this valve piston in any event separates the pump connection 10 from the tank connection 14 . Furthermore, the valve piston 22 operates in conjunction with an energy accumulator 24 , it being possible to activate a self-adjusting fluid flow between the appliance connection 18 and the tank connection 14 by means of a control device identified as a whole as 26 . The control device 26 in question consists in particular of a fluid flow regulator which is integrated into the valve piston 12 and is explained in greater detail in what follows with respect to its structure and function. The fluid flow regulator in question has a flow regulating piston 28 which is controlled in the valve piston 22 so as to be longitudinally positionable, the inner circumference of the valve piston 22 encircling the outer circumference of the flow regulating piston 28 . The flow regulating piston 28 in turn rests on another energy accumulator 30 , the direction of operation of which is opposite that of the first energy accumulator 24 . Along the longitudinal axis 20 of the valve box 12 , and so in the center, the flow regulating piston 28 has a fluid channel 32 , which, at least in one displaced position of the flow regulating piston 28 as shown in FIG. 1, discharges into a fluid channel 34 the valve piston 22 which, again in the displaced position shown in FIG. 1, establishes a fluid-conducting connection with the separate tank connection 16 in the valve box 12 . In each displaced position of the valve piston 22 the latter separates the first tank connections 14 from the other separate tank connection 16 . The fluid channel 32 of the flow regulating piston 28 may, on its side facing the appliance connection 18 , be sealed by a control piston 36 which is held in the direction of this locking position by way of the first energy accumulator 24 . On its end in this direction the fluid channel 32 has a throat and, as shown in FIG. 1, discharges into the open at its end with reduced cross-section. The control piston 36 in question has as contact component a cup 38 which is in the form of a hemisphere and, with its curved frontal engaging surface, is provided for fluid-conducting introduction into the fluid channel 32 of the flow regulating piston 28 . In the position illustrated and in every other shifted position the cup 38 leaves the free end of the fluid channel 32 with its reduced cross-section clear for passage of fluid. As is to be seen in the line of sight to FIG. 1, a flange-like enlargement 40 is mounted above the cup 38 ; the free end of the pressure spring which forms the first energy accumulator 24 rests on this enlargement. The other free end of the pressure spring as energy accumulator 24 is in contact with an end stop 42 which is screwed into the valve box 12 on the end opposite the pump connection 10 and is secured in this manner. On its end facing the end stop 42 the control piston 36 has a stop face 44 which maintains axial spacing from the end stop as seen in the longitudinal direction of the longitudinal axis 20 also when the valve is in the usual operating state. As a result of the action of the energy accumulator 24 and of the control piston 36 , the flow regulating piston 28 is held down in the direction of a lower position, as viewed in the line of sight toward FIG. 1 . Acting against the direction of action in question, within the integrated system represented by flow regulating piston 28 and valve piston 22 , there is another energy accumulator 30 in the form of a pressure accumulator one lower end of which rests on the valve piston 22 and the other end of which rests on the flow regulating piston 28 in such a way that it is introduced into the fluid channel 32 of the flow regulating piston 28 . For the purpose of such introduction the diameter of the fluid channel 32 of the flow regulating piston 28 is enlarged in the direction of its lower free end. The flow regulating piston 28 is guided in the interior of the valve piston 22 , which for this purpose has a cylindrical interior recess; when a fluid connection has been established among the separate tank connection 16 , the fluid channel 34 , and the fluid channel 32 , the upper front ends of valve piston 22 and flow regulating piston 28 come together while more or less level in one plane which extends transversely to the longitudinal axis 20 . In the configuration in question the lower free end of the flow regulating piston 28 is spaced an axial distance from the lower receiving end of the valve piston 22 such that the latter comes to rest flush against the upper edge of the part of the fluid channel 34 which faces the interior of the valve piston 22 . The side of the fluid channel 34 facing away from the valve piston 22 widens into an annular recess 46 the upper edge of which fits snugly, in the circuit diagram shown in FIG. 1, against the separate tank connection 16 . In addition, the lower free end of the other energy accumulator 30 in the form of the pressure spring is received into an interior recess on the bottom side of the valve piston 22 and in this way supported in this position. The appliance connection 18 discharges into a valve space 48 of the valve box 12 through which extend the control piston 36 and the first energy accumulator 24 . In addition, the valve box 12 has for the valve piston 22 , on its side facing the valve space 48 , a stop surface 50 , in the form of a retaining ring (not shown), for example. As a result, the valve piston 22 may be freely positioned downward in the line of sight to FIG. 1 of the pump connection 10 , while the positioning path is limited in the opposite direction. As a function of the pressure loads on the appliance connection 18 , also designated as load connection, the cup 38 as closing component is held back against the action of the energy accumulators 24 and 30 and/or the flow regulating piston 28 is positioned downward in the valve piston 22 as viewed in the line of sight to FIG. 1, so that fluid channel 32 is fully released. The configuration in question may be adjusted so that the volume flow to the appliance may be reduced free of load by a constant value so that proportional load-independent control is also possible if leaks occur. The block diagram presented in FIG. 2 shows how proportional load-independent control may be effected for this purpose. This figure illustrates a basic circuit concept of a so-called load sensing system, a fixed-displacement pump 52 being employed in the embodiment shown in FIG. 2 . Variable-displacement pumps (not shown) may be appropriately used rather than the fixed-displacement pumps in question. The purpose of the load sensing referred to is achievement of optimized energy utilization, the load pressure returned to a regulating element in the form of the valve being employed to adjust the output provided hydraulically by way of the fixed-displacement pump 52 to that of an appliance, in this instance in the form of a hydraulic working cylinder 54 . Proportional control elements are generally employed to drive the appliance, in this instance in the form of the hydraulic working cylinder 54 , even on the basis of the operating comfort desired; exclusively for the sake of greater simplicity of presentation an adjustable throttle 56 is used here in place of the proportional control valves as drive component for the hydraulic working cylinder 54 . The appliance volume flow may be varied, and accordingly the working cylinder 54 actuated, by way of the control throttle or control stop 56 . The appliance volume flow is determined from the free throttle opening cross-section Q and the pressure difference Δp at the throttle 56 as measured at sensing points 58 upstream and downstream from the throttle 56 . In the load sensing systems in question the valve piston 22 is assigned the function of a kind of piston manometer, the flow regulating piston 28 as part of the control device 26 reducing the volume flow to the appliance 54 independently of load by a constant value in the event of leaks in the hydraulic appliance circuit 62 . The difference Δp as measured between the two sensing points 58 is accordingly predetermined by the spring tension of the energy accumulator 24 which engages the piston manometer in the form of the valve piston 22 and is kept constant by adjustment of the piston manometer. Equilibrium then more or less prevails at the valve piston 22 as piston manometer: Δ     p = spring     tension     of     energy     accumulator     24 surface     area     of     valve     piston     22 = constant Consequently, a directly proportional relationship is obtained between the free cross-section Q of the control throttle 56 and the appliance volume flow proper. If an additional force in the form of an additional load in the direction of the appliance circuit 62 is applied to the cylinder rod 64 of the working cylinder 54 , the piston manometer in the form of the valve piston 22 is forced into its blocked position as shown in FIG. 2, in which the pump connection 10 is separated from the first tank connection 14 and the fixed displacement pump 52 correspondingly delivers to the piston side 66 of the working cylinder 54 the amount of fluid required to offset the additional load applied. If, however, the working cylinder 54 removes load in the opposite direction, the applied load in question must be offset by a constant load and the fixed-displacement pump 52 , which otherwise is secured in the direction of the tank 68 by a pressure control valve 60 , now pumps directly by way of the freed connection to the first tank connections 14 , the valve piston 22 as piston manometer being retracted in a suitably elevated displacement position in the direction of the appliance connection 18 (see FIG. 1 ). If a plurality of appliances is connected to a load sensing system and is supplied by a common fixed-displacement pump 52 , the load sensing lines must be linked so that suitable load sensing control of the valve configuration described may be exerted. If leaks occur in the hydraulic circuit 62 to which the appliance 54 is connected or in the appliance 54 itself, the control device designated as a whole as 26 makes certain that the appliance pressure does not rise undesirably to the pump level, something which would have the result that the load sensing would be disabled. This is prevented by the control device 26 , which relieves the load on the appliance connection 18 to the tank 16 . The volume flow to the appliance is reduced by a constant value independently of load by the flow regulating device, so that proportional load-independent control is provided. Slowing of the operating process by the appliance 54 with increase in load pressure is reliably prevented. Integration of the flow regulating device into the piston manometer results in a compact structure with a small number of components and the maintenance situation is improved in the case of the valve claimed for the invention.
The invention relates to a valve that comprises at least one pump connection ( 10 ), one tank connection ( 14 ) and one consumer connection ( 18 ), and a valve piston ( 22 ) that is displaced within the valve box ( 12 ). Said valve piston separates the pump connection ( 10 ) from the tank connection ( 14 ) in at least one blocked position and interacts with an energy accumulator ( 24 ). A fluid stream that flows between the consumer connection ( 18 ) and the tank connection ( 14 ) is controlled by means of a control device ( 26 ). The control device ( 26 ) is configured as a fluid stream control that is integrated in the valve piston ( 22 ) and that allows, contrary to known valves which use a diaphragm construction, reduction, by a constant value, of the volume flow to the consumer in a load-independent manner, thereby allowing for a proportional load-independent control.
Briefly summarize the invention's components and working principles as described in the document.
[ "FIELD OF THE INVENTION The invention relates to a valve having at least one pump connection, one tank connection, and one appliance connection and a valve piston positionable inside the valve housing, which piston separates the pump connection from the tank connection in at least one blocked position and which operates in conjunction with an energy accumulator, a self-adjusting fluid flow being controllable by means of a control device between the appliance connection and the tank connection.", "BACKGROUND OF THE INVENTION Such valves are routinely used in so-called hydraulic load sensing systems or control means and operate there like a piston manometer, directing an unneeded pump feed flow back to the tank.", "In order to prevent leakages in the appliance circuit from raising the appliance pressure to the performance level of the pump and thereby possibly disabling the load sensing system, the load on the appliance connection to the tank is to be removed.", "Such load removal is currently effected in a cost-effective manner by use of aperture control means, the aperture preferably being integrated directly into the piston manometer or being used separately in a control unit which is part of the load sensing control mechanism.", "A disadvantage of these known solutions with the aperture design feature is the pressure dependence of the volume flow draining to the tank.", "In the case of appliances whose volume flow is independent of load, proceeds by way of proportional valves, for example, this then results in constant slowing of the appliance with increase in the load pressure, something which has an especially negative effect in the case of appliances with a low volume flow.", "SUMMARY OF THE INVENTION On the basis of this state of the art the invention pursues the object of further improving known valves to the end that such valves will not be characterized by the disadvantages described, especially when employed in so-called load sensing systems.", "In addition, it is to be possible to reduce the valve cost efficiently and so that the valve occupies little space.", "The object as thus formulated is attained by means of a valve having the features specified in claim 1 .", "Since, as specified in the descriptive portion of claim 1 , the control device consists of a fluid flow controller integrated into the valve piston it is possible, in contrast with known valve solutions, to use the aperture design to reduce the volume flow to the appliance, independently of the load, by a constant value, so that proportional load-independent control is effected.", "The disadvantages of the state of the art as described, in the form of slowing of the appliance in particular, are thus reliably excluded.", "The solution with the fluid flow controller claimed for the invention can be cost effectively applied and space-saving installation in the valve itself is possible as a result of integration of the fluid flow controller into the valve box.", "Since the valve claimed for the invention has only a few structural components, reliability of operation is ensured which benefits the load sensing system as a whole.", "Other advantageous embodiments are specified in the dependent claims.", "BRIEF DESCRIPTION OF THE DRAWINGS The valve claimed for the invention is explained in detail in what follows with reference to the drawing, in which, in diagrammatic form and not to scale, FIG. 1 presents a longitudinal section through the valve claimed for the invention;", "FIG. 2 in the form of a circuit diagram, illustrates use of the valve as shown in FIG. 1 in the case of a load sensing system with an operating cylinder as hydraulic appliance.", "DETAILED DESCRIPTION OF THE INVENTION The valve shown in longitudinal section in FIG. 1 has a pump connection 10 , specifically on the front end of a valve box 12 , designed as a screw-in cartridge to be secured in control units or the like for subsequent use.", "Configuration as a built-in set or the like is also possible.", "The valve box 12 has at its end facing the pump connection 10 two first tank connections 14 diametrically opposite each other.", "As viewed in the line of sight to FIG. 1, mounted above them (as shown in the left half of the illustration) is another separate tank connection 16 whose free open cross-section is smaller than the corresponding diameter area of the first tank connections 14 .", "On the other hand, another cross bore which serves as appliance connection 18 has been introduced into the valve box 12 .", "The tank connections 14 and 16 also are in the form of cross bores in the valve box 12 .", "The connections 14 , 16 , and 18 in question extend more or less transversely to the longitudinal axis 20 of the valve box 12 .", "The pump connection 10 , in contrast, is mounted along the longitudinal axis 20 of the valve box 12 , on the front side of the latter.", "Mounted in the valve box 12 so as to be longitudinally positionable is a valve piston 22 the external circumference of which is provided with pressure relief ducts by conventional means, which accordingly are not described in detail.", "In one of its blocked positions as shown in FIG. 1 this valve piston in any event separates the pump connection 10 from the tank connection 14 .", "Furthermore, the valve piston 22 operates in conjunction with an energy accumulator 24 , it being possible to activate a self-adjusting fluid flow between the appliance connection 18 and the tank connection 14 by means of a control device identified as a whole as 26 .", "The control device 26 in question consists in particular of a fluid flow regulator which is integrated into the valve piston 12 and is explained in greater detail in what follows with respect to its structure and function.", "The fluid flow regulator in question has a flow regulating piston 28 which is controlled in the valve piston 22 so as to be longitudinally positionable, the inner circumference of the valve piston 22 encircling the outer circumference of the flow regulating piston 28 .", "The flow regulating piston 28 in turn rests on another energy accumulator 30 , the direction of operation of which is opposite that of the first energy accumulator 24 .", "Along the longitudinal axis 20 of the valve box 12 , and so in the center, the flow regulating piston 28 has a fluid channel 32 , which, at least in one displaced position of the flow regulating piston 28 as shown in FIG. 1, discharges into a fluid channel 34 the valve piston 22 which, again in the displaced position shown in FIG. 1, establishes a fluid-conducting connection with the separate tank connection 16 in the valve box 12 .", "In each displaced position of the valve piston 22 the latter separates the first tank connections 14 from the other separate tank connection 16 .", "The fluid channel 32 of the flow regulating piston 28 may, on its side facing the appliance connection 18 , be sealed by a control piston 36 which is held in the direction of this locking position by way of the first energy accumulator 24 .", "On its end in this direction the fluid channel 32 has a throat and, as shown in FIG. 1, discharges into the open at its end with reduced cross-section.", "The control piston 36 in question has as contact component a cup 38 which is in the form of a hemisphere and, with its curved frontal engaging surface, is provided for fluid-conducting introduction into the fluid channel 32 of the flow regulating piston 28 .", "In the position illustrated and in every other shifted position the cup 38 leaves the free end of the fluid channel 32 with its reduced cross-section clear for passage of fluid.", "As is to be seen in the line of sight to FIG. 1, a flange-like enlargement 40 is mounted above the cup 38 ;", "the free end of the pressure spring which forms the first energy accumulator 24 rests on this enlargement.", "The other free end of the pressure spring as energy accumulator 24 is in contact with an end stop 42 which is screwed into the valve box 12 on the end opposite the pump connection 10 and is secured in this manner.", "On its end facing the end stop 42 the control piston 36 has a stop face 44 which maintains axial spacing from the end stop as seen in the longitudinal direction of the longitudinal axis 20 also when the valve is in the usual operating state.", "As a result of the action of the energy accumulator 24 and of the control piston 36 , the flow regulating piston 28 is held down in the direction of a lower position, as viewed in the line of sight toward FIG. 1 .", "Acting against the direction of action in question, within the integrated system represented by flow regulating piston 28 and valve piston 22 , there is another energy accumulator 30 in the form of a pressure accumulator one lower end of which rests on the valve piston 22 and the other end of which rests on the flow regulating piston 28 in such a way that it is introduced into the fluid channel 32 of the flow regulating piston 28 .", "For the purpose of such introduction the diameter of the fluid channel 32 of the flow regulating piston 28 is enlarged in the direction of its lower free end.", "The flow regulating piston 28 is guided in the interior of the valve piston 22 , which for this purpose has a cylindrical interior recess;", "when a fluid connection has been established among the separate tank connection 16 , the fluid channel 34 , and the fluid channel 32 , the upper front ends of valve piston 22 and flow regulating piston 28 come together while more or less level in one plane which extends transversely to the longitudinal axis 20 .", "In the configuration in question the lower free end of the flow regulating piston 28 is spaced an axial distance from the lower receiving end of the valve piston 22 such that the latter comes to rest flush against the upper edge of the part of the fluid channel 34 which faces the interior of the valve piston 22 .", "The side of the fluid channel 34 facing away from the valve piston 22 widens into an annular recess 46 the upper edge of which fits snugly, in the circuit diagram shown in FIG. 1, against the separate tank connection 16 .", "In addition, the lower free end of the other energy accumulator 30 in the form of the pressure spring is received into an interior recess on the bottom side of the valve piston 22 and in this way supported in this position.", "The appliance connection 18 discharges into a valve space 48 of the valve box 12 through which extend the control piston 36 and the first energy accumulator 24 .", "In addition, the valve box 12 has for the valve piston 22 , on its side facing the valve space 48 , a stop surface 50 , in the form of a retaining ring (not shown), for example.", "As a result, the valve piston 22 may be freely positioned downward in the line of sight to FIG. 1 of the pump connection 10 , while the positioning path is limited in the opposite direction.", "As a function of the pressure loads on the appliance connection 18 , also designated as load connection, the cup 38 as closing component is held back against the action of the energy accumulators 24 and 30 and/or the flow regulating piston 28 is positioned downward in the valve piston 22 as viewed in the line of sight to FIG. 1, so that fluid channel 32 is fully released.", "The configuration in question may be adjusted so that the volume flow to the appliance may be reduced free of load by a constant value so that proportional load-independent control is also possible if leaks occur.", "The block diagram presented in FIG. 2 shows how proportional load-independent control may be effected for this purpose.", "This figure illustrates a basic circuit concept of a so-called load sensing system, a fixed-displacement pump 52 being employed in the embodiment shown in FIG. 2 .", "Variable-displacement pumps (not shown) may be appropriately used rather than the fixed-displacement pumps in question.", "The purpose of the load sensing referred to is achievement of optimized energy utilization, the load pressure returned to a regulating element in the form of the valve being employed to adjust the output provided hydraulically by way of the fixed-displacement pump 52 to that of an appliance, in this instance in the form of a hydraulic working cylinder 54 .", "Proportional control elements are generally employed to drive the appliance, in this instance in the form of the hydraulic working cylinder 54 , even on the basis of the operating comfort desired;", "exclusively for the sake of greater simplicity of presentation an adjustable throttle 56 is used here in place of the proportional control valves as drive component for the hydraulic working cylinder 54 .", "The appliance volume flow may be varied, and accordingly the working cylinder 54 actuated, by way of the control throttle or control stop 56 .", "The appliance volume flow is determined from the free throttle opening cross-section Q and the pressure difference Δp at the throttle 56 as measured at sensing points 58 upstream and downstream from the throttle 56 .", "In the load sensing systems in question the valve piston 22 is assigned the function of a kind of piston manometer, the flow regulating piston 28 as part of the control device 26 reducing the volume flow to the appliance 54 independently of load by a constant value in the event of leaks in the hydraulic appliance circuit 62 .", "The difference Δp as measured between the two sensing points 58 is accordingly predetermined by the spring tension of the energy accumulator 24 which engages the piston manometer in the form of the valve piston 22 and is kept constant by adjustment of the piston manometer.", "Equilibrium then more or less prevails at the valve piston 22 as piston manometer: Δ   p = spring   tension   of   energy   accumulator   24 surface   area   of   valve   piston   22 = constant Consequently, a directly proportional relationship is obtained between the free cross-section Q of the control throttle 56 and the appliance volume flow proper.", "If an additional force in the form of an additional load in the direction of the appliance circuit 62 is applied to the cylinder rod 64 of the working cylinder 54 , the piston manometer in the form of the valve piston 22 is forced into its blocked position as shown in FIG. 2, in which the pump connection 10 is separated from the first tank connection 14 and the fixed displacement pump 52 correspondingly delivers to the piston side 66 of the working cylinder 54 the amount of fluid required to offset the additional load applied.", "If, however, the working cylinder 54 removes load in the opposite direction, the applied load in question must be offset by a constant load and the fixed-displacement pump 52 , which otherwise is secured in the direction of the tank 68 by a pressure control valve 60 , now pumps directly by way of the freed connection to the first tank connections 14 , the valve piston 22 as piston manometer being retracted in a suitably elevated displacement position in the direction of the appliance connection 18 (see FIG. 1 ).", "If a plurality of appliances is connected to a load sensing system and is supplied by a common fixed-displacement pump 52 , the load sensing lines must be linked so that suitable load sensing control of the valve configuration described may be exerted.", "If leaks occur in the hydraulic circuit 62 to which the appliance 54 is connected or in the appliance 54 itself, the control device designated as a whole as 26 makes certain that the appliance pressure does not rise undesirably to the pump level, something which would have the result that the load sensing would be disabled.", "This is prevented by the control device 26 , which relieves the load on the appliance connection 18 to the tank 16 .", "The volume flow to the appliance is reduced by a constant value independently of load by the flow regulating device, so that proportional load-independent control is provided.", "Slowing of the operating process by the appliance 54 with increase in load pressure is reliably prevented.", "Integration of the flow regulating device into the piston manometer results in a compact structure with a small number of components and the maintenance situation is improved in the case of the valve claimed for the invention." ]
FIELD OF THE INVENTION The invention relates to a laryngoscope, and more particularly to a laryngoscope that may be used with many differing video monitors and that also may be used as either a video laryngoscope or as a direct visualization laryngoscope having a blade with a smooth upper surface so as not to interfere with direct visualization of a patient's trachea. BACKGROUND OF THE INVENTION A number of medical procedures require ventilation be provided to the patient, which may be provided through an endotracheal tube. This tube may be inserted into the trachea. It should be noted that when the tube is inserted, the patient is asleep hyperoxygenated and then paralyzed for the procedure, and therefore not breathing. As the ventilator is not yet in operation, the physician must work quickly to insert the endotracheal tube. With the advent of endoscopic equipment and small cameras, instrumentation can enable viewing of the cords and larynx on a video screen facilitating the intubation of the patient in a relatively quick and safe manner. In some instances it has been determined that direct visualization of the cords and larynx is preferred over the video method. However, video laryngoscopes due to their specialized construction, traditionally do not allowed for intubation by direct visualization. Rather, a physician must discard the video laryngoscope and obtain a traditional non-video laryngoscope to perform this procedure. This disadvantageously leads to delay in intubation of the patient due at least in part to the fact that the physician has to change instruments. It is highly desirable to reduce any cause for delay in the intubation process. U.S. Pat. Nos. 6,655,377 (“the '377 patent”) and 6,543,447 (“the '447 patent”) disclose video laryngoscopes having a lifter portion that is long enough to extend into the laryngopharynx and operably engage the epiglottis of the patient. One function of the lifter portion is to hold the intubation tube with the video device is positioned on a lower side of the blade opposite to the lifter portion. While this configuration functions as a video laryngoscope, the lifter portion extends upward from the upper surface of the blade such that any direct visualization by a physician is virtually impossible. As such, a physician would have to discard and retrieve a separate laryngoscope to perform this procedure. Another problem that traditional video laryngoscopes face is the limited interface ability they have with monitors. For example, a video laryngoscope typically is designed and can only be used with a single type of monitor, e.g. either an O.R. monitor or a P.C. This is disadvantageous as the physician may desire to switch monitors, for example, the laryngoscope may be attached to an O.R. monitor but the physician wants to connect the laryngoscope to a relatively small portable computer monitor as the patient is transported. The laryngoscope would then have to be replaced with a device capable of functioning with a P.C. monitor. Yet another problem associated with video laryngoscopes is the fact that, many imaging chips are positioned in a cavity or enclosure at a distal end of the laryngoscope blade and are enclosed by a transparent window. However, the window often becomes fogged during the procedure thereby limiting the ability of the physician to see clearly. SUMMARY OF THE INVENTION It is therefore desired to provide a video laryngoscope that may be used either as a video laryngoscope or as a direct visualization laryngoscope for intubation of a patient. It is also desired to provide a video laryngoscope that is capable of functioning with many differing monitors. It is further desired to provide a video laryngoscope that is compatible with many differing signal formats. It is still further desired to provide a video laryngoscope that provides for de-fogging to maintain clear visualization for the physician. These and other objectives are achieved by providing a laryngoscope that utilizes a blade having a smooth upper surface so as not to interfere with the physician's direct visualization of the areas in and around the laryngopharynx during intubation. The laryngoscope is provided with a digital imaging chip and an illumination device, e.g. a Light Emitting Diode (LED) for illumination of an area to be viewed. It is contemplated that the digital imaging chip may comprise, for example, either a CCD, a C-Mos chip, or the like capable of, for instance, generating image data from processing reflected light picked up from an area to be viewed and/or from processing digital images from a camera in order to further improve the quality of the digital images. Further, it is contemplated that the digital imaging chip may be provided as a “hard-wired” or as a “wireless” device for transmitting image data picked up from the area to be viewed. In one advantageous embodiment, a digital imaging chip and an LED are positioned in an enclosure that may be detachably connectable to, for example, the laryngoscope blade. The enclosure is provided with an elongated case and be provided with a coupling mechanism for coupling the enclosure to the handle and/or blade. In one embodiment, the imaging chip and the LED are provided at a distal end of the enclosure, while the coupling mechanism is provided at the opposite proximal end of the enclosure such that electrical connections may be provided for the imaging chip and the LED. In this manner, electrical power may be transmitted to the LED to illuminate the area ahead of the blade, while the digital imaging chip may generate and transmit image data back to imaging circuitry positioned in the handle. It is further provided that the LED may be provided as a relatively high-powered LED and is used to heat a window at the distal end of the enclosure such that the window is maintained free of fogging. The LED may be run, for example, at half power. In addition, the enclosure may be positioned in a channel provided in the blade to securely hold the enclosure. In another advantageous embodiment, a universal control circuit, such as a camera, may be positioned in the handle of the laryngoscope. The universal camera may be removable and may include a connector to couple to the handle, or may include a connector that couples directly to the enclosure. The universal camera may include many differing configurations including, for example but not limited to, a USB version 2.0 for connection to a Windows XP device over a USB 2.0 cable, a composite video version for connection to a NTSC over a composite video cable, a UWB wireless video version (USB) using a USB 2.0 signal, and/or a UWB wireless video version using an NSTC signal to name a few. In this manner, any sensitive electronics may be removed from the handle, for example, during the sterilization process so that they are not exposed to the relatively high temperatures encountered during the process. The blade of the laryngoscope is advantageously provided with a smooth upper surface such that the physician may use the laryngoscope either in the “video mode” or in may intubate a patient by direct visualization as desired. It is further contemplated that a plurality of blades may be detachably connectable to the handle, while the enclosure is detachably connectable to the blade and/or handle. While it is preferred to locate the digital imaging device and the LED in the enclosure that is attachable to the blade, it is contemplated that one or both of the digital imaging device and/or the LED may be positioned in the removable universal camera, which may, for example, be a digital camera having a dedicated digital imaging chip. It is still further contemplated that the laryngoscope may be provided with a direct wired connection to, for example, a video monitor, or may be provided with a wireless connection to the display equipment, which may comprise use of Ultra Wide Band (UWB) technology. Accordingly, in one advantageous embodiment a laryngoscope system is provided comprising a handle having a cavity located therein, the cavity having a connector, a blade coupled to the handle and a camera detachably connectable to the connector. The laryngoscope system also comprises a sleeve coupled to the camera, an illuminating device for providing illuminating light to an area in front of the distal end of the blade and a digital imaging device for generating image data of the area in front of the distal end of the blade. In addition, the laryngoscope system includes a display coupled to the camera, the display receiving and displaying the image data. In another advantageous embodiment a method for intubating a patient with a laryngoscope is provided comprising the steps of coupling a camera to a connector located in a cavity in a handle, coupling a blade to the handle and coupling a sleeve to the camera. The method includes the steps of transmitting illuminating light to an area in front of the distal end of the blade, generating image data of the area in front of the distal end of the blade and transmitting the image data to the camera. The method further includes the steps of coupling a display to the control circuit camera, transmitting the image data to the display and displaying the image data on a display. Other objects of the invention and its particular features and advantages will become more apparent from consideration of the following drawings and accompanying detailed description. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of one advantageous embodiment of the present invention. FIG. 2 is a block diagram of sleeve according to FIG. 1 . FIG. 3 is a perspective view of the embodiment according to FIG. 1 . FIG. 4 is another perspective view of the embodiment according to FIG. 1 . FIG. 5 is still another perspective view of the embodiment according to FIG. 1 . FIG. 6 is yet another perspective view of the embodiment according to FIG. 1 . FIG. 7 is still another perspective view of the embodiment according to FIG. 1 . DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views. One advantageous embodiment of the present invention is variously illustrated in FIGS. 1-7 including laryngoscope 200 . FIGS. 1 and 2 are block diagrams illustrating various functional arrangements of laryngoscope 200 , while FIGS. 3-7 are various prospective views of an advantageous embodiment of the present invention. Laryngoscope 200 generally comprises a camera 202 , which is insertable into or detachably connectable to a handle 204 of the laryngoscope 200 . In addition, a blade 206 is coupled to handle 204 and a sleeve 214 may be coupled to camera 202 for transmitting image data to the camera, which is in turn, transmitted to a display 250 . FIG. 1 illustrates use of, for example, a cable 252 or use of a wireless coupling to display 250 . It is contemplated that cable 252 may provide electrical power to camera 202 and may also transmit image data to display 250 . However, in a wireless embodiment, a battery may be located in handle 204 . Referring to FIG. 2 , an imaging device 260 and an illumination device 262 are each positioned at a distal end of sleeve 214 . Also illustrated is window 264 . Illumination device 262 may comprise, for example, an LED positioned adjacent to window 264 . Illumination device 262 is provided for illumination of an area to be viewed, such as, for example, an area ahead of the distal end of blade 206 . It is contemplated that illumination device 262 may operate in a fully ON state when laryngoscope 200 is in use, or may, in one advantageous embodiment, be pulsed in sync with imaging device 260 . In addition, the LED may be used to de-fog window 264 . In one embodiment, the LED provided as a relatively high-powered LED and run at half power or more providing both illumination and heating of the window 264 to provide a de-fogging function. In a battery-powered version, the battery may comprise any battery type as is commonly used in industry and is contemplated that it may have a twelve-hour battery life. Further, the battery may in one advantageous embodiment be rechargeable. Imaging device 260 may pick up reflected light from an area to be viewed and translates the reflected light into image data that is transmitted for display on display 250 . This transmission may advantageously comprise a hard-wired connection or may be wireless. For hard-wired connections, the cable may comprise an electrical connection providing power to camera 202 and image data to display 250 . It is further contemplated that data signals, control signals and power may all be transmitted over a signal channel thereby minimizing the size of the interconnecting cables. For wireless transmission, any acceptable transmission means may be used including but not limited to, for example, radio-frequency transmission or the like. In one embodiment, transmission circuitry is positioned in handle 204 for transmission of the image data to display 250 . The coupling between laryngoscope 200 and display 250 is illustrated in FIG. 1 as either a curved line with arrows in two different directions (wireless) or the straight line with arrows in two different directions (hard-wired). Display 250 may comprise virtually any commercially available video system and monitor for display of the image data generated by imaging device 260 . In an advantageous embodiment, wireless transmission may comprise an UWB transmission. As UWB systems transmit signals across a much wider frequency than conventional systems, a relatively large amount of data may be transmitted. This is advantageous for video medical systems, where relatively high resolution is beneficial and signal lag is undesirable. A number of UWB technologies may effectively be used including, for example, Multiband Orthogonal Frequency Division Modulation (OFDM) or Direct Sequence Ultra-Wideband (DS-UWB). It is contemplated that imaging device 260 may comprise, in one advantageous embodiment, a CMOS chip (e.g. OmniVision's OV7660 VGA CMOS electronic camera sensor). The CMOS chip may be made relatively small in size, utilizes very little power and is inexpensive to manufacture and may be connected to any necessary drive electronics using a flex circuit. In addition, the signal format may be selected to utilize nonsinusoidal signals, which will not interfere with the sinewave spectrum so as to minimize any interference in existing operating room equipment. This advantage may be is achieved, at least in part because the transmitted power may be spread over a relatively large bandwidth such that the amount of power at any one frequency band at any time is relatively small. In one advantageous embodiment, blade 206 is detachably connectable to handle 204 . Advantageously, blade 206 is provided slightly curved upward as a traditional Macintosh style blade, but could be provided relatively straight as per the traditional Foregger-Magill blade. As can be seen in FIG. 4 , blade 206 is advantageously provided with a relatively smooth upper surface 208 , which in part, allows the physician to use laryngoscope 200 either in the video mode (e.g. viewing a video screen during the intubation process) or via direct visualization. It is contemplated that in one embodiment, blade 206 may be provided as a rigid material, such as a metal or an alloy, but is not limited to these material compositions. As seen in FIGS. 5 and 6 , blade 206 is provided with a stepped portion 210 such that a cavity is formed in the lower portion 212 of blade 206 for receiving sleeve 214 , which may be detachably connectable to blade 206 . As in the previously described embodiments, the illumination may be provided by an LED, which in this embodiment, is positioned in sleeve 214 . In addition, the imaging device may also be positioned in sleeve 214 and may comprise a digital imaging device such as a CMOS device or chip. As seen in FIG. 1 , camera 202 is insertable into a cavity 216 of handle 204 and lies essentially flush with handle 204 with fully inserted ( FIG. 4 ). It is contemplated that the device may provide an audible “click” when camera 202 is fully inserted into cavity 216 providing an audible indication to the user that the coupling of camera 202 to handle 204 is complete. It is further contemplated that a lock, such as an interference fitting between camera 202 and cavity 216 , may be provided to maintain camera 202 securely coupled to handle 204 during use. Also provided on the exterior surface of camera 202 is protrusion 222 , which is provided as a ridge running along a longitudinal length of camera 202 . Protrusion 222 is provided to engage with a channel 224 located in cavity 216 . In this manner, the camera 202 may only be removed from cavity 216 by longitudinally sliding the camera 202 out of cavity 216 . A coupler 218 is provided at the insertion end of camera 202 , which is designed to engage with a complementary connector (not shown) positioned inside cavity 216 of handle 204 . Depending upon the application, the coupler may couple, electrical cables/channels, optical cables/channels and/or combinations thereof. In addition, cable 220 may be provided to channel electrical signals, optical signals/energy and/or combinations thereof between camera 202 and the video system (Display). Although the invention has been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other modifications and variations will be ascertainable to those of skill in the art.
A laryngoscope including a control circuit and a camera having a housing enclosing the camera that is detachably connectable to a handle, where the camera functions and is compatible with a wide variety of displays. The laryngoscope may optionally be used in either the video mode where the user views a display presenting image data of the area ahead of the blade, or the user may use the laryngoscope in the direct visualization where the user uses the laryngoscope in a traditional manner directly viewing the area ahead of the blade during the intubation procedure. When used in the video mode, an LED is positioned adjacent to a window enclosing the digital image sensor to defog the window.
Briefly describe the main idea outlined in the provided context.
[ "FIELD OF THE INVENTION The invention relates to a laryngoscope, and more particularly to a laryngoscope that may be used with many differing video monitors and that also may be used as either a video laryngoscope or as a direct visualization laryngoscope having a blade with a smooth upper surface so as not to interfere with direct visualization of a patient's trachea.", "BACKGROUND OF THE INVENTION A number of medical procedures require ventilation be provided to the patient, which may be provided through an endotracheal tube.", "This tube may be inserted into the trachea.", "It should be noted that when the tube is inserted, the patient is asleep hyperoxygenated and then paralyzed for the procedure, and therefore not breathing.", "As the ventilator is not yet in operation, the physician must work quickly to insert the endotracheal tube.", "With the advent of endoscopic equipment and small cameras, instrumentation can enable viewing of the cords and larynx on a video screen facilitating the intubation of the patient in a relatively quick and safe manner.", "In some instances it has been determined that direct visualization of the cords and larynx is preferred over the video method.", "However, video laryngoscopes due to their specialized construction, traditionally do not allowed for intubation by direct visualization.", "Rather, a physician must discard the video laryngoscope and obtain a traditional non-video laryngoscope to perform this procedure.", "This disadvantageously leads to delay in intubation of the patient due at least in part to the fact that the physician has to change instruments.", "It is highly desirable to reduce any cause for delay in the intubation process.", "U.S. Pat. Nos. 6,655,377 (“the '377 patent”) and 6,543,447 (“the '447 patent”) disclose video laryngoscopes having a lifter portion that is long enough to extend into the laryngopharynx and operably engage the epiglottis of the patient.", "One function of the lifter portion is to hold the intubation tube with the video device is positioned on a lower side of the blade opposite to the lifter portion.", "While this configuration functions as a video laryngoscope, the lifter portion extends upward from the upper surface of the blade such that any direct visualization by a physician is virtually impossible.", "As such, a physician would have to discard and retrieve a separate laryngoscope to perform this procedure.", "Another problem that traditional video laryngoscopes face is the limited interface ability they have with monitors.", "For example, a video laryngoscope typically is designed and can only be used with a single type of monitor, e.g. either an O.R. monitor or a P.C.", "This is disadvantageous as the physician may desire to switch monitors, for example, the laryngoscope may be attached to an O.R. monitor but the physician wants to connect the laryngoscope to a relatively small portable computer monitor as the patient is transported.", "The laryngoscope would then have to be replaced with a device capable of functioning with a P.C. monitor.", "Yet another problem associated with video laryngoscopes is the fact that, many imaging chips are positioned in a cavity or enclosure at a distal end of the laryngoscope blade and are enclosed by a transparent window.", "However, the window often becomes fogged during the procedure thereby limiting the ability of the physician to see clearly.", "SUMMARY OF THE INVENTION It is therefore desired to provide a video laryngoscope that may be used either as a video laryngoscope or as a direct visualization laryngoscope for intubation of a patient.", "It is also desired to provide a video laryngoscope that is capable of functioning with many differing monitors.", "It is further desired to provide a video laryngoscope that is compatible with many differing signal formats.", "It is still further desired to provide a video laryngoscope that provides for de-fogging to maintain clear visualization for the physician.", "These and other objectives are achieved by providing a laryngoscope that utilizes a blade having a smooth upper surface so as not to interfere with the physician's direct visualization of the areas in and around the laryngopharynx during intubation.", "The laryngoscope is provided with a digital imaging chip and an illumination device, e.g. a Light Emitting Diode (LED) for illumination of an area to be viewed.", "It is contemplated that the digital imaging chip may comprise, for example, either a CCD, a C-Mos chip, or the like capable of, for instance, generating image data from processing reflected light picked up from an area to be viewed and/or from processing digital images from a camera in order to further improve the quality of the digital images.", "Further, it is contemplated that the digital imaging chip may be provided as a “hard-wired”", "or as a “wireless”", "device for transmitting image data picked up from the area to be viewed.", "In one advantageous embodiment, a digital imaging chip and an LED are positioned in an enclosure that may be detachably connectable to, for example, the laryngoscope blade.", "The enclosure is provided with an elongated case and be provided with a coupling mechanism for coupling the enclosure to the handle and/or blade.", "In one embodiment, the imaging chip and the LED are provided at a distal end of the enclosure, while the coupling mechanism is provided at the opposite proximal end of the enclosure such that electrical connections may be provided for the imaging chip and the LED.", "In this manner, electrical power may be transmitted to the LED to illuminate the area ahead of the blade, while the digital imaging chip may generate and transmit image data back to imaging circuitry positioned in the handle.", "It is further provided that the LED may be provided as a relatively high-powered LED and is used to heat a window at the distal end of the enclosure such that the window is maintained free of fogging.", "The LED may be run, for example, at half power.", "In addition, the enclosure may be positioned in a channel provided in the blade to securely hold the enclosure.", "In another advantageous embodiment, a universal control circuit, such as a camera, may be positioned in the handle of the laryngoscope.", "The universal camera may be removable and may include a connector to couple to the handle, or may include a connector that couples directly to the enclosure.", "The universal camera may include many differing configurations including, for example but not limited to, a USB version 2.0 for connection to a Windows XP device over a USB 2.0 cable, a composite video version for connection to a NTSC over a composite video cable, a UWB wireless video version (USB) using a USB 2.0 signal, and/or a UWB wireless video version using an NSTC signal to name a few.", "In this manner, any sensitive electronics may be removed from the handle, for example, during the sterilization process so that they are not exposed to the relatively high temperatures encountered during the process.", "The blade of the laryngoscope is advantageously provided with a smooth upper surface such that the physician may use the laryngoscope either in the “video mode”", "or in may intubate a patient by direct visualization as desired.", "It is further contemplated that a plurality of blades may be detachably connectable to the handle, while the enclosure is detachably connectable to the blade and/or handle.", "While it is preferred to locate the digital imaging device and the LED in the enclosure that is attachable to the blade, it is contemplated that one or both of the digital imaging device and/or the LED may be positioned in the removable universal camera, which may, for example, be a digital camera having a dedicated digital imaging chip.", "It is still further contemplated that the laryngoscope may be provided with a direct wired connection to, for example, a video monitor, or may be provided with a wireless connection to the display equipment, which may comprise use of Ultra Wide Band (UWB) technology.", "Accordingly, in one advantageous embodiment a laryngoscope system is provided comprising a handle having a cavity located therein, the cavity having a connector, a blade coupled to the handle and a camera detachably connectable to the connector.", "The laryngoscope system also comprises a sleeve coupled to the camera, an illuminating device for providing illuminating light to an area in front of the distal end of the blade and a digital imaging device for generating image data of the area in front of the distal end of the blade.", "In addition, the laryngoscope system includes a display coupled to the camera, the display receiving and displaying the image data.", "In another advantageous embodiment a method for intubating a patient with a laryngoscope is provided comprising the steps of coupling a camera to a connector located in a cavity in a handle, coupling a blade to the handle and coupling a sleeve to the camera.", "The method includes the steps of transmitting illuminating light to an area in front of the distal end of the blade, generating image data of the area in front of the distal end of the blade and transmitting the image data to the camera.", "The method further includes the steps of coupling a display to the control circuit camera, transmitting the image data to the display and displaying the image data on a display.", "Other objects of the invention and its particular features and advantages will become more apparent from consideration of the following drawings and accompanying detailed description.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of one advantageous embodiment of the present invention.", "FIG. 2 is a block diagram of sleeve according to FIG. 1 .", "FIG. 3 is a perspective view of the embodiment according to FIG. 1 .", "FIG. 4 is another perspective view of the embodiment according to FIG. 1 .", "FIG. 5 is still another perspective view of the embodiment according to FIG. 1 .", "FIG. 6 is yet another perspective view of the embodiment according to FIG. 1 .", "FIG. 7 is still another perspective view of the embodiment according to FIG. 1 .", "DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views.", "One advantageous embodiment of the present invention is variously illustrated in FIGS. 1-7 including laryngoscope 200 .", "FIGS. 1 and 2 are block diagrams illustrating various functional arrangements of laryngoscope 200 , while FIGS. 3-7 are various prospective views of an advantageous embodiment of the present invention.", "Laryngoscope 200 generally comprises a camera 202 , which is insertable into or detachably connectable to a handle 204 of the laryngoscope 200 .", "In addition, a blade 206 is coupled to handle 204 and a sleeve 214 may be coupled to camera 202 for transmitting image data to the camera, which is in turn, transmitted to a display 250 .", "FIG. 1 illustrates use of, for example, a cable 252 or use of a wireless coupling to display 250 .", "It is contemplated that cable 252 may provide electrical power to camera 202 and may also transmit image data to display 250 .", "However, in a wireless embodiment, a battery may be located in handle 204 .", "Referring to FIG. 2 , an imaging device 260 and an illumination device 262 are each positioned at a distal end of sleeve 214 .", "Also illustrated is window 264 .", "Illumination device 262 may comprise, for example, an LED positioned adjacent to window 264 .", "Illumination device 262 is provided for illumination of an area to be viewed, such as, for example, an area ahead of the distal end of blade 206 .", "It is contemplated that illumination device 262 may operate in a fully ON state when laryngoscope 200 is in use, or may, in one advantageous embodiment, be pulsed in sync with imaging device 260 .", "In addition, the LED may be used to de-fog window 264 .", "In one embodiment, the LED provided as a relatively high-powered LED and run at half power or more providing both illumination and heating of the window 264 to provide a de-fogging function.", "In a battery-powered version, the battery may comprise any battery type as is commonly used in industry and is contemplated that it may have a twelve-hour battery life.", "Further, the battery may in one advantageous embodiment be rechargeable.", "Imaging device 260 may pick up reflected light from an area to be viewed and translates the reflected light into image data that is transmitted for display on display 250 .", "This transmission may advantageously comprise a hard-wired connection or may be wireless.", "For hard-wired connections, the cable may comprise an electrical connection providing power to camera 202 and image data to display 250 .", "It is further contemplated that data signals, control signals and power may all be transmitted over a signal channel thereby minimizing the size of the interconnecting cables.", "For wireless transmission, any acceptable transmission means may be used including but not limited to, for example, radio-frequency transmission or the like.", "In one embodiment, transmission circuitry is positioned in handle 204 for transmission of the image data to display 250 .", "The coupling between laryngoscope 200 and display 250 is illustrated in FIG. 1 as either a curved line with arrows in two different directions (wireless) or the straight line with arrows in two different directions (hard-wired).", "Display 250 may comprise virtually any commercially available video system and monitor for display of the image data generated by imaging device 260 .", "In an advantageous embodiment, wireless transmission may comprise an UWB transmission.", "As UWB systems transmit signals across a much wider frequency than conventional systems, a relatively large amount of data may be transmitted.", "This is advantageous for video medical systems, where relatively high resolution is beneficial and signal lag is undesirable.", "A number of UWB technologies may effectively be used including, for example, Multiband Orthogonal Frequency Division Modulation (OFDM) or Direct Sequence Ultra-Wideband (DS-UWB).", "It is contemplated that imaging device 260 may comprise, in one advantageous embodiment, a CMOS chip (e.g. OmniVision's OV7660 VGA CMOS electronic camera sensor).", "The CMOS chip may be made relatively small in size, utilizes very little power and is inexpensive to manufacture and may be connected to any necessary drive electronics using a flex circuit.", "In addition, the signal format may be selected to utilize nonsinusoidal signals, which will not interfere with the sinewave spectrum so as to minimize any interference in existing operating room equipment.", "This advantage may be is achieved, at least in part because the transmitted power may be spread over a relatively large bandwidth such that the amount of power at any one frequency band at any time is relatively small.", "In one advantageous embodiment, blade 206 is detachably connectable to handle 204 .", "Advantageously, blade 206 is provided slightly curved upward as a traditional Macintosh style blade, but could be provided relatively straight as per the traditional Foregger-Magill blade.", "As can be seen in FIG. 4 , blade 206 is advantageously provided with a relatively smooth upper surface 208 , which in part, allows the physician to use laryngoscope 200 either in the video mode (e.g. viewing a video screen during the intubation process) or via direct visualization.", "It is contemplated that in one embodiment, blade 206 may be provided as a rigid material, such as a metal or an alloy, but is not limited to these material compositions.", "As seen in FIGS. 5 and 6 , blade 206 is provided with a stepped portion 210 such that a cavity is formed in the lower portion 212 of blade 206 for receiving sleeve 214 , which may be detachably connectable to blade 206 .", "As in the previously described embodiments, the illumination may be provided by an LED, which in this embodiment, is positioned in sleeve 214 .", "In addition, the imaging device may also be positioned in sleeve 214 and may comprise a digital imaging device such as a CMOS device or chip.", "As seen in FIG. 1 , camera 202 is insertable into a cavity 216 of handle 204 and lies essentially flush with handle 204 with fully inserted ( FIG. 4 ).", "It is contemplated that the device may provide an audible “click”", "when camera 202 is fully inserted into cavity 216 providing an audible indication to the user that the coupling of camera 202 to handle 204 is complete.", "It is further contemplated that a lock, such as an interference fitting between camera 202 and cavity 216 , may be provided to maintain camera 202 securely coupled to handle 204 during use.", "Also provided on the exterior surface of camera 202 is protrusion 222 , which is provided as a ridge running along a longitudinal length of camera 202 .", "Protrusion 222 is provided to engage with a channel 224 located in cavity 216 .", "In this manner, the camera 202 may only be removed from cavity 216 by longitudinally sliding the camera 202 out of cavity 216 .", "A coupler 218 is provided at the insertion end of camera 202 , which is designed to engage with a complementary connector (not shown) positioned inside cavity 216 of handle 204 .", "Depending upon the application, the coupler may couple, electrical cables/channels, optical cables/channels and/or combinations thereof.", "In addition, cable 220 may be provided to channel electrical signals, optical signals/energy and/or combinations thereof between camera 202 and the video system (Display).", "Although the invention has been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other modifications and variations will be ascertainable to those of skill in the art." ]
BACKGROUND OF THE PRESENT INVENTION [0001] 1. Field of Invention [0002] The present invention relates to a process for purifying and recycling printing and dyeing wastewater, and more particularly to a purifying and recycling process for deeply treating printing and dyeing wastewater based on a combination of nanometer catalytic microelectrolysis technology and membrane technology. [0003] 2. Description of Related Arts [0004] Textile industry generally includes spinning, printing and dyeing, chemical fiber, clothing and manufacture of textile devices. With the fast development of the economy, the printing and dyeing industry also enters a fast developing period, the devices and technology are improved obviously, the production process and devices are changed continuously, and the printing and dyeing companies develop very fast. So far, there are more than 2,000 printing and dyeing companies above designated size in China. The printing and dyeing processes refer to physical and chemical process to various textile material fibers, yarns, and cloths in production, and include pre-treating, dyeing, printing, and after-treating of textile materials which are together called printing and dyeing processes. At present, the development of the textile technology is guided with ecological fabrics production and green production technology, catches the source through multi-channels including processes, adjuvants, and devices, emphasizes the ecological problems of each link, optimizes the textile processes hard, and reduces the consumption of chemical agents, water and energy, so as to achieve the goal of high efficiency, high speed and environment-friendliness. A great effort is paid to environment-friendly dye stuff adjuvants, new processes saving water, energy and reducing emission and new devices at home and abroad, and an obvious progress is made in printing and dyeing technology with no water or less water, printing and dyeing of painting, and utility model of textile saving energy and water. However, despite the fast development of the technology of saving water and treating wastewater in the textile printing and dyeing industry, the textile printing and dyeing wastewater is still an important pollution source in China's industrial system. According to the statistics of Ministry of Environmental Protection of the People's Republic of China, the printing and dyeing wastewater drained by the printing and dyeing industry is the fifth largest in all the industrial departments of China. The character of the printing and dyeing wastewater as an important environment pollution source is firstly large amount. At present, the printing and dyeing products are about 800,000˜900,000 tons in the world, and China has 150,000 tons, ranking in the top. About 10%˜15% of the printing and dyeing components are drained into the environment along with wastewater in production and use of the printing and dyeing products. The printing and dyeing industry and textile printing and dyeing industry are high developed, and the printing and dyeing wastewater pollutes the environment more seriously. In 2004, the printing and dyeing industry drained 1.36 billions m 3 , and the pollutant is the sixth largest in all the industrial departments calculated by COD. Secondly, the type of printing and dyeing components as environmental pollutants have many species and complex structures. The synthesis printing and dyeing components have more than 30,000 species, and more than 80% of them contain complex organic compounds of azo bond and poly-aromatic. Printing and dyeing industry is one of the industries of extremely serious environmental pollution in the chemical industries. The printing and dyeing wastewater has large chromaticity, high concentration of organic matters, complex components, many hardly biodegradable substances, and contains a large number of inorganic salts, sulfides, etc., are intractable industrial wastewater. The printing and dyeing components are hard to be removed due to its complex aromatic hydrocarbons molecular structure, which are desired to exist stably in water environment or under illumination and oxidants when designing and production. Thirdly, most printing and dyeing components are toxic non-degradable organic matters having strong chemical stabilization, and carcinogenic, teratogenic and mutagenic effects. Even the concentration of the remained printing and dyeing components are low in the wastewater, it will also reduce the light transmittance of water body after draining into the water body, so as to cause damage to the water ecological system. Therefore, efficiently treating the printing and dyeing wastewater has become an important problem. [0005] The printing and dyeing wastewater has characters such as high concentration and large number of species of pollutants, containing toxic and harmful components and high chromaticity. The ordinary treating methods to the printing and dyeing wastewater at home and abroad comprise physical methods, chemical methods, biological methods, and etc. [0006] 1. Physical Methods [0007] The physical methods mainly comprise flotation method of adsorption, membrane separation method, ultrasonic gas vibration method, and distillation method. The adsorption method is applied mostly in the physical methods. At present, the activated carbon adsorption method is mainly adopted in international. The method is very effective for removal of dissolved organic matters, but can not remove colloids and hydrophobic dyeing, and has good adsorption properties to the water-soluble printing and dyeing components in cationic printing and dyeing, direct printing and dyeing, acid printing and dyeing, reactive printing and dyeing. [0008] Adsorption flotation method first absorbs printing and dyeing ion and other soluble substances from the wastewater with highly dispersed powdery inorganic adsorbents such as bentonite and kaolin, then adds the flotation agent to obtain hydrophobic particles by airfloating, the removal efficiency of acid printing and dyeing, cationic printing and dyeing, and direct printing and dyeing can be more than 92%. [0009] The membrane technology applied in treating printing and dyeing wastewater mainly comprises ultra-filtraten and reverse osmosis. The ultra-filtraten technology has a decolourization rate of 80%˜97%, and a TOC removal rate of 60%˜85% in treating scattered printing and dyeing wastewater. The reverse osmosis technology has a removal rate of soluble solid of 85%˜-99%, and an average recycle rate of 75%˜85%. [0010] The ultrasonic technology can become an effective method of treating wastewater by controlling the ultrasonic frequency and saturation of gas. The Zhangjiagang Jiuzhou Fine Chemical Industry treats printing and dyeing wastewater with the FBZ wastewater treatment equipment designed according to ultrasonic gas vibration technology, and has an average chroma removal rate of 97%, a COD Cr removal rate of 90.6%, and a total pollution load reduction rate of 85.9%. [0011] 2. Chemical Methods [0012] Chemical methods mainly comprise chemical coagulation method, chemical oxidation method, photochemical catalytic oxidation method, and electrochemical method. The chemical coagulation method is a frequently used method of treating printing and dyeing wastewater, and was thought to be one of the most efficient and economic decoloring technologies. The chemical oxidation method is a main method of decoloring printing and dyeing wastewater, decolors by destroying printing and dyeing color groups with various oxidation methods. Depending on the oxidants and oxidation condition, the chemical oxidation method is divided into ozone oxidation method and deep oxidation method. Furthermore, the photochemical catalytic oxidation method as a deep oxidation technology for reducing organic matters develops fast in recent years. Referring to ZHANG Gui-Ian, Photodegradation of dyes in water using rotation reactor [J]. JOURNAL OF TEXTILE RESEARCH, 2005, 26(3): 109-111, the photochemical catalytic oxidation method achieves good decoloring effect in degrading printing and dyeing wastewater. The electrochemical method purifies printing and dyeing wastewater by electrode reaction. [0013] Microelectrolysis method is an electrochemical technology using iron and carbon filler corroded in the electrolyte solution to form numerous tiny primary cells to treat wastewater. It is a wastewater treating method combining electrolysis, coagulation, electrolytic flocculation, adsorption and other physical and chemical effects in one. In the treatment of printing and dyeing wastewater, printing and dyeing molecules are first adsorbed onto the carbon surface, and have oxidation or reduction reactions in the two poles. The electrode can also be used for electrolysis. Referring to Jia Jinping, Shen Zhemin, Wang Wenhua, The Status Quo and Progress on Treating Methods of Wastewater Containing Dyestaff, 2000, 191:26-29, the integrated performance of electrode conductivity, adsorption, catalytic, redox, the flotation of activated carbon fiber electrode is used to achieve a one-stop process of adsorption—electrode reaction—flocculation and desorption, and the decolorization rate is 98%, COD Cr removal rate is greater than 80%. Referring to YAN Bin, FU Hai-yan, CHAI Tian, JIN Lei, SHI Qian, Application of Microelectrolysis Method in Dyehouse Wastewater Treatment, JOURNAL OF XIAMEN UNIVERSITY OF TECHNOLOGY, 2008, 16(1):18-22, decoloring and COD Cr removal effects to wastewater produced by cotton series and chemical fiber synthetic woven fabrics with microelectrolysis technology of iron—carbon electrode is studied, when the mass ratio of iron to carbon is 2:1, HRT is 1.5 h, the COD removal rate is up to 55%, chromaticity removal rate is 95%, BOD/COD increased from 0.3 to 0.5. Referring to Luo Jingsheng, Zeng Kangmei, Zuo Jingying, Li Xin, Liu Fude, TREATMENT OF DYE WASTEWATER BY MICROELECTROLYSIS PROCESS, TECHNOLOGY OF WATER TREATMENT, 2005, 31(11):67-70, treating production wastewater containing dyestuff, dye intermediate, and adjuvant with circulating iron—carbon microelectrolysis method is studied. The result shows that pH of the raw water has great affect to treating effect. When pH is within 1˜5, the lower pH is, the better the treating effect is, and when pH is 1, COD removal rate is about 60%, chromaticity removal rate is above 94%. Referring to Deng Xihong, Wang Chao, An Engineering Example of Treating Dyeing Wasterwater Using Microelectrolysis—Physical and Chemical—Biochemical Method, Environmental Science and Management, 2008, 33(3):120-122, the printing and dyeing wastewater of high pollutant concentration, large concentration fluctuations, alkaline, high chromaticity, and biorefractory property is treated with Microelectrolysis—Physical and Chemical—Biochemical Method, which runs continuously for three months, and the result shows that the method runs stably, has low investment and low treating cost, (0.765 RMB per ton), the removal rates of COD, BOD, SS and chromaticity are respectively above 94%, 96%, 89%, and 96%. The indexes of effluent quality all meet emission standards. EpolitoW illiam J,HanbaeYang, et al. studies microelectrolysis to RB4 (Reactive Blue4) wastewater. The experimental result shows that the decoloring rate gradually increases with the decreasing of pH, and increasing of stirring, experimental temperature and ionic strength. There are also many other reports about treating printing and dyeing wastewater with electrochemical method. [0014] 3. Biochemical Methods [0015] The printing and dyeing wastewater is biorefractory, so if desiring treating with biochemical methods, MLSS of the activated sludge can be increased, and biochemical performance of the activated sludge can be improved, or efficient strains are used to increase biochemical effect. Breeding and training excellent decolorization flora is an important development direction of the biochemical methods. The research of formation of engineering bacteria with multiple plasmids efficiently decoloring printing and dyeing wastewater by use of mutation breeding, protoplast fusion, and genetic engineering techniques. The recent studies show that the dominant bacteria of the Pseudomonas bacteria, Sphaerotilus natans, Arthrobacter, Bacillus subtilis, and oxidative yeast have a considerable effect of in degradation of printing and dyeing wastewater. [0016] In recent years, the combination of chemical and physical methods for treating printing and dyeing wastewater, or the combination of biological treatment and physical treatment for printing and dyeing wastewater has developed rapidly. Chinese patent of ZL 200710008643.0 discloses a treating method for printing and dyeing wastewater based on membrane technology, which combines chemical coagulation and sedimentation, biological treatment, and reverse osmosis separation technology for treating combines printing and dyeing wastewater. [0017] Although the above methods all have good treating effect, the following problems still exist. [0018] In the physical and chemical aspect, activated carbon has good adsorption effect, but activated carbon is difficult to regenerate, has high cost, and thus its application is limited. Many companies turn to other adsorbent of cheaper and easy-to-get materials. Electrolysis method and oxidation method has certain effect in removing chromaticity of printing and dyeing wastewater, but COD removal is often not satisfactory, the cost of the treatment agents is relatively high. Many new means of oxidation are still in the research phase, and have not being industrialized. [0019] In biochemical aspect, printing and dyeing products are typical fine chemical products, with characteristics of small volume and numerous varieties, and its structure is complex, production process is long, operations of nitration, condensation, reduction, oxidation, diazotization, and coupling are often accompanied from raw materials to finished products. By-products are many, production yield is low, wastewater has complex organic composition, chemical reaction of printing and dyeing production, and processes of separation, refining, and washing all use water as solvent, and thus water consumption is large. Biochemical treatment of printing and dyeing wastewater has the advantages of less investment, but there are still disadvantages that micro-organisms are difficult to adapt to printing and dyeing wastewater, water quality is volatile, and toxicity is big. And problems of sludge disposal, anaerobic biogas processing and complex management also exist. In addition, although the iron-carbon microelectrolysis electrode made some progress in the treatment of printing and dyeing wastewater, the consumption of iron-carbon produces a lot of precipitation, so that treated wastewater is difficult to use, only to meet emission standards. [0020] The treatment of printing and dyeing wastewater using a single method is often difficult to achieve the desired results. The conventional method is to combines each treating methods, which has drawbacks of long process, high operating cost, and unstable water quality. The treated wastewater ordinarily reaches to the emission standard II. The discharged wastewater are processed with a variety of methods of biochemical, chemical, and physical and chemical treatment, so the physical and chemical properties are very stable, any following decolorizing purification becomes very difficult, and general methods are difficult to further decolor or purify the wastewater. The deeply treated wastewater reaching emission standard II will have long-term impact on the environment. On the other hand, the current fresh water resources are increasingly lacking, and water supply has become increasing problem. If deeply treated printing and dyeing wastewater can be reused as recycled water, it will not only significantly reduce the impact on the environment, but also save a lot of fresh water resources. SUMMARY OF THE PRESENT INVENTION [0021] An object of the present invention is to provide a purifying device for deeply treating printing and dyeing wastewater, based on a combination of nanometer catalytic microelectrolysis technology membrane technology, and conventional treating technology, has low cost, high efficiency and obtaining recycled water, with respect to existing problems of high cost, low efficiency and water waste in conventional treating methods for printing and dyeing wastewater, and a purifying process therefor. [0022] The deeply treated printing and dyeing wastewater according to the present invention refers to printing and dyeing wastewater reaching emission standard II after pre-treatment. The printing and dyeing wastewater reaching emission standard II after pre-treatment can be printing and dyeing wastewater reaching emission standard II after treatment by at least one method of biochemical method, chemical method, physical and chemical method. [0023] A purifying device for deeply treating printing and dyeing wastewater according to the present invention comprises: [0024] a nanometer catalytic microelectrolysis system, for processing steps of nanometer catalytic microelectrolysis, neutralization precipitation, crude filteration and adsorption and filteration of activated carbon, comprising: a first stop valve, a first pump, a nanometer catalytic microelectrolysis tank, a neutralization tank, a sand filteration tank and an adsorption and filteration device of granular active carbon, wherein an inlet of the first stop valve is connected externally to an outlet of printing and dyeing wastewater, an inlet of the first pump is connected with an outlet of the first stop valve, an outlet of the first pump is connected with an inlet of the nanometer catalytic microelectrolysis tank and an inlet of the neutralization tank, an outlet of the nanometer catalytic microelectrolysis tank is connected with the inlet of the neutralization tank via a one-way valve, an inlet of the sand filteration tank is connected with an outlet of the neutralization tank, and an inlet of the adsorption and filteration device of granular active carbon is connected with an outlet of the sand filteration tank; [0025] a membrane filtration and separation system, for filtering and separating the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis to obtain dialyzed liquid and concentrated liquid, comprising: a second stop valve, a second pump, a security filter, a high-pressure pump, a reverse osmosis filtration membrane system and a dialyzed liquid storage tank, wherein the membrane filtration and separation system pumps the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis into the membrane filtration and separation system with the high-pressure pump after being filtered by the security filter, the dialyzed liquid and the concentrated liquid are obtained by separating with membrane filtering, the dialyzed liquid enters into the dialyzed liquid storage tank to be recycled water, the concentrated liquid has a first part reflowing to be processed by circulated membrane filtration and separation, a second part reflowing into the step of nanometer catalytic microelectrolysis to be reused, and a rest part drained, wherein an inlet of the second stop valve is connected with the outlet of purified wastewater of the adsorption and filteration device of granular active carbon, an outlet of the second stop valve is connected with the reverse osmosis filtration membrane system via the second pump, the security filter, and the high-pressure pump in turn, and a dialyzed liquid outlet of the reverse osmosis filtration membrane system is connected with an inlet of the dialyzed liquid storage tank via a first valve; and [0026] a membrane washing regeneration system, for washing the membrane filtration and separation system, comprising a washing liquid tank and a communication pipe, wherein an inlet of the washing liquid tank is connected with an outlet of the dialyzed liquid storage tank via a third stop valve and a second valve, a first outlet of the washing liquid tank is connected with the reverse osmosis filtration membrane system via the second valve and the third stop valve, a second outlet of the washing liquid tank is connected with the security filter via the second valve, the third stop valve and the second pump, and a third outlet of the washing liquid tank is connected with the dialyzed liquid storage tank via the second valve, a first concentrated liquid outlet of the reverse osmosis filtration membrane system reflows to be connected with an inlet of the high-pressure pump via the third stop valve, a second concentrated liquid outlet of the reverse osmosis filtration membrane system reflows to be connected with the nanometer catalytic microelectrolysis tank via the third stop valve to be reused. [0027] A purifying process for deeply treating printing and dyeing wastewater according to the present invention comprises: [0028] after pumping the printing and dyeing wastewater with the pump, feeding a first part of the printing and dyeing wastewater into the nanometer catalytic microelectrolysis tank to be processed by catalytic microelectrolysis, and then into the neutralization tank, feeding a second part of the printing and dyeing wastewater directly into the neutralization tank to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation, filtering by the crude filter tank, and then pumping into the adsorption and filteration device of granular active carbon to be adsorbed and filtered, so as to remove chlorine and solid impurity produced by microelectrolysis, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater, wherein SDI thereof should be less than 5. [0029] A working voltage of the nanometer catalytic microelectrolysis is 2˜18 V, preferably 4˜10 V, a current intensity is 5˜5000 A, preferably 50˜1000 A. The deeply treated printing and dyeing wastewater containing NaCl flows into the neutralization tank via a one-way valve after producing nascent state chlorine by microelectrolysis. The second part of the printing and dyeing wastewater directly enters into the neutralization tank via a pipe and the one-way valve. Nanometer catalytic microelectrolysis has the following advantages. (1) The nascent state chlorine produced by nanometer catalytic microelectrolysis kills microorganism in the wastewater, and reduces live bodies of microorganism to be less than 30/ml, so as to eliminate pollution of the membrane materials. (2) Organic matters in the wastewater are oxidated and degraded, remaining dyestuff is degraded and decolored, and COD Cr is reduced. (3) The wastewater is purified by crude filtering and fine filtering relatively big coagulation of suspended matter and colloid in the wastewater under effect of electric field. (4) Heavy metal ions in the wastewater move towards a negative pole of the nanometer catalytic microelectrolysis tank and form precipitate thereon, so as to reduce heavy metal ions in the wastewater. [0030] The deeply treated wastewater still has deep color and higher COD Cr after being treated by multiple processing of biochemical, chemical, physical and chemical methods, and ordinary chemical treatment is very difficult to further decolorize and decrease COD Cr . In the natural environment, even after several days, the wastewater will not fade. Treating the deeply treated wastewater with nanometer catalytic microelectrolysis can decolor the wastewater and significantly reduce COD Cr within 2 to 5 minutes. [0031] A concentration of NaCl of the printing and dyeing wastewater is 6 0 / 00 ˜50 0 / 00 , preferably 0.6 0 / 00 ˜1.3 0 / 00 , and can be increased to 6 0 / 00 ˜50 0 / 00 with industrial NaCl when low. [0032] The step of nanometer catalytic microelectrolysis produces nascent state chlorine by nanometer catalytic microelectrolysis of ⅓ to ⅕ of the deeply treated printing and dyeing wastewater, so as to oxidate and degrade organic matters in the wastewater kill microorganism in the wastewater, and produce coagulation of suspended matter, colloid, and charged corpuscle in the wastewater to form relatively larger particles under effect of electric field. [0033] The step of neutralization precipitation mixes the wastewater treated with nanometer catalytic microelectrolysis, which contains nascent state chlorine, with the rest ⅔ to ⅘ of the deeply treated printing and dyeing wastewater not treated with nanometer catalytic microelectrolysis, the nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater and kills the microorganism in the wastewater. Crystal nucleus produced by coagulation of microelectrolysis precipitates the suspended matter, solid particles, and colloid. [0034] The crude filteration is one selected from the group consisting of sand filteration, and multi-media filteration. [0035] The membrane filtration and separation system is one selected from the group consisting of a reverse osmosis membrane filtration and separation system, and a nanofiltration membrane filtration and separation system. [0036] A reverse osmosis membrane of the reverse osmosis membrane filtration system, is a reverse osmosis membrane having NaCl retention rate of 98%, a membrane structure is rolling membrane module or a tubular membrane module, a working condition is from room temperature to 45° C., and a working pressure is 7˜25 bar. [0037] A nanofiltration membrane of the nanofiltration membrane filtration and separation system, is a nanofiltration membrane having MgSO 4 retention rate of 98%, a membrane structure is rolling membrane module or a tubular membrane module, a working condition is from room temperature to 45° C., and a working pressure is 3˜20 bar. [0038] The present invention not only overcomes the defects of high cost by single-use of the membrane filtration and separation process, or adsorption process, but also overcomes the defects of unsatisfying treating effect of conventional methods of treating printing and dyeing wastewater and polluting the environment by the drained wastewater, turning the decayed into wonder, and using the waste as a resource by purifying existing deeply treated printing and dyeing wastewater and recycling to reuse. Compared with prior art, The present invention has the following outstanding advantages of: [0039] 1. fast degrading remaining dyestuff of the deeply treated printing and dyeing wastewater to eliminate the color thereof within 2 to 5 minutes; [0040] 2. low investment; [0041] 3. deep treating degree, so that pollution is greatly reduced; [0042] 4, low cost, and large economic efficiency; [0043] 5, high utilization of water resources; and [0044] 6, greatly reducing discharge of wastewater. BRIEF DESCRIPTION OF THE DRAWINGS [0045] The FIGURE is a sketch view of a structure of a purifying device for deeply treating printing and dyeing wastewater according to a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0046] The present invention finishes a designing of a process for purifying deeply treating printing and dyeing wastewater and reusing recycled water after deep and systematic comparative study of composition and property of the existing deeply treating printing and dyeing wastewater, and conventional treating processes. The present invention provides a process especially adapted for purifying deeply treating printing and dyeing wastewater and reusing recycled water by combining methods of nanometer catalytic microelectrolysis, neutralization, crude filteration, adsorption and filteration of activated carbon, and membrane filtration. [0047] A preferred embodiment of the present invention describing detailedly is as follows accompanying with the FIGURE. [0048] Referring to the FIGURE, a purifying device for deeply treating printing and dyeing wastewater according to a preferred embodiment of the present invention, comprising: [0049] a nanometer catalytic microelectrolysis system, for processing steps of nanometer catalytic microelectrolysis, neutralization precipitation, crude filteration and adsorption and filteration of activated carbon, comprising: a first stop valve 11 , a first pump 12 , a nanometer catalytic microelectrolysis tank 13 , a neutralization tank 16 , a sand filteration tank 17 and an adsorption and filteration device of granular active carbon 18 , wherein an inlet of the first stop valve 11 is connected externally to an outlet of printing and dyeing wastewater, an inlet of the first pump 12 is connected with an outlet of the first stop valve 11 , an outlet of the first pump 12 is connected with an inlet of the nanometer catalytic microelectrolysis tank 13 and an inlet of the neutralization tank 16 , an outlet of the nanometer catalytic microelectrolysis tank 13 is connected with the inlet of the neutralization tank 16 via a one-way valve, an inlet of the sand filteration tank 17 is connected with an outlet of the neutralization tank 16 , and an inlet of the adsorption and filteration device of granular active carbon 18 is connected with an outlet of the sand filteration tank 17 ; [0050] a membrane filtration and separation system, for filtering and separating the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis to obtain dialyzed liquid and concentrated liquid, comprising: a second stop valve 21 , a second pump 22 , a security filter 23 , a high-pressure pump 24 , a reverse osmosis filtration membrane system 25 , a first valve 26 , a second valve 27 , and a dialyzed liquid storage tank 28 , wherein the membrane filtration and separation system pumps the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis into the membrane filtration and separation system with the high-pressure pump 24 after being filtered by the security filter 23 , the dialyzed liquid and concentrated liquid are obtained by separating with membrane filtering, the dialyzed liquid enters into the dialyzed liquid storage tank 28 to be recycled water, the concentrated liquid has a first part reflowing to be processed by circulated membrane filtration and separation, a second part reflowing into the step of nanometer catalytic microelectrolysis to be reused, and a rest part drained, wherein an inlet of the second stop valve 21 is connected with the outlet of purified wastewater of the adsorption and filteration device of granular active carbon 18 , an outlet of the second stop valve 21 is connected with the reverse osmosis filtration membrane system 25 via the second pump 22 , the security filter 23 , and the high-pressure pump 24 in turn, and a dialyzed liquid outlet of the reverse osmosis filtration membrane system 25 is connected with an inlet of the dialyzed liquid storage tank 28 via the first valve 26 and the second valve 27 ; and [0051] a membrane washing regeneration system, for washing the membrane filtration and separation system, comprising: a third stop valve 31 , a washing liquid tank 32 , a third valve 33 , a fourth valve 34 , a fifth valve 35 , a fourth stop valve 36 , a fifth stop valve 37 , a sixth stop valve 38 , a seventh stop valve 39 , and a communication pipe, wherein an inlet of the washing liquid tank 32 is connected with an outlet of the dialyzed liquid storage tank 28 via a third stop valve 31 and a second valve 27 , a first outlet of the washing liquid tank 28 is connected with the reverse osmosis filtration membrane system 25 via the third valve 33 and the fourth stop valve 36 , a second outlet of the washing liquid tank 32 is connected with the security filter 25 via the fourth valve 34 , the sixth stop valve 38 and the second pump 22 , and a third outlet of the washing liquid tank 32 is connected with the dialyzed liquid storage tank 28 via the fifth valve 35 and the second valve 27 , a first concentrated liquid outlet of the reverse osmosis filtration membrane system 25 reflows to be connected with an inlet of the high-pressure pump 24 via the fourth stop valve 36 and the fifth stop valve 37 , a second concentrated liquid outlet of the reverse osmosis filtration membrane system 25 reflows to be connected with the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused. [0052] A purifying process for printing and dyeing wastewater of a purifying device for deeply treating printing and dyeing wastewater according to a preferred embodiment of the present invention in the FIGURE is shown as follows. Example 1 [0053] A process for purifying deeply treating printing and dyeing wastewater of 150 tons per day and reusing recycled water. [0054] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 1. [0000] TABLE 1 Measured No. Item Unit value 1 COD Cr mg/L 156 2 SS mg/L 110 3 turbidity NTU 6 4 chromaticity 80 5 saltness ‰ 6.6 6 pH 8.3 7 conductivity μS/cm 7200 [0055] The deeply treating printing and dyeing wastewater of 150 tons per day is drawn via the first pump 12 for 7.5T/H. At the beginning, a first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 1.5T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 2.8T/H, after catalytic microelectrolysis, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 6.0T/H via the T-cock and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater. [0056] A working voltage of the nanometer catalytic microelectrolysis is 8˜9V, a current intensity is 500˜510 A. The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater. A measured SDI is 2.5. [0057] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 , the dialyzed liquid is stored in the dialyzed liquid storage tank 28 via the first valve 26 , the T-cock, and the second valve 27 , and supplies water to a clean water storage tank 32 via the T-cock and the third stop valve 31 . [0058] A reverse osmosis membrane of the reverse osmosis membrane filtration system 25 , is a reverse osmosis rolling membrane having NaCl retention rate of 98%, a working condition is 32˜35° C., a working pressure is 9·12 bar, a membrane flux is 20 ml/cm 2 , flowing speeds of the dialyzed liquid and the concentrated liquid are respectively 5.3T/H and 4.9T/H, the concentrated liquid reflows to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 1.4 T/H, reflows into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 1.3 T/H, and drains the rest for 2.6 T/H. The recycled rate of the wastewater is 65%, qualities of the recycled water are shown in Table 2, and indexes of the concentrated liquid is shown in Table 3. [0000] TABLE 2 Measured No. Item Unit value 1 COD Cr mg/L 9 2 SS mg/L 15 3 turbidity NTU 0.8 4 chromaticity 15 5 pH 6.7 6 conductivity μS/cm 10 [0000] TABLE 3 Measured No. Item Unit value 1 COD Cr mg/L 156 2 SS mg/L 50 3 turbidity NTU 2 4 chromaticity 30 5 saltness ‰ 3.7 6 pH 8.5 7 conductivity μS/cm 9100 Example 2 [0059] A process for purifying deeply treating printing and dyeing wastewater of 3,000 tons per day and reusing recycled water. [0060] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 4. [0000] TABLE 4 Measured No. Item Unit value 1 COD Cr mg/L 181 2 SS mg/L 160 3 turbidity NTU 7.5 4 chromaticity 13 5 pH 7.6 6 conductivity μS/cm 6000 [0061] The deeply treating printing and dyeing wastewater is drawn via the first pump 12 for 150 T/H. A first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 50 T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 75 T/H, wherein the deeply treating printing and dyeing wastewater is 50 T/H, the concentrated liquid after reflowing for catalytic microelectrolysis for 25 T/H, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 100 T/H via the T-cock, a pipe and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater. [0062] Due to low saltness of the deeply treating printing and dyeing wastewater, industrial NaCl is added to increase the saltness up to 12.5%, and then nanometer catalytic microelectrolysis is processed. A working voltage of the nanometer catalytic microelectrolysis is 5˜6 V, a current intensity is 1560˜1580 A. The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater. A measured SDI is 2.9. [0063] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 to obtain the dialyzed liquid and the concentrated liquid, flowing speeds of the dialyzed liquid and the concentrated liquid are respectively 73.5 T/H and 127.5T/H, the dialyzed liquid is stored in the dialyzed liquid storage tank 28 via the first valve 26 , the T-cock, and the second valve 27 for 127.5T/H, and supplies water to a clean water storage tank 32 via the T-cock and the third stop valve 31 . The concentrated liquid reflows to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 26 T/H, reflows into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 25.0 T/H, and drains the rest for 22.5 T/H. The recycled rate of the wastewater is 85%, qualities of the recycled water are shown in Table 5, and indexes of the concentrated liquid are shown in Table 6. [0064] A nanofiltration membrane of the nanofiltration membrane filtration and separation system, is a nanofiltration rolling membrane having MgSO 4 retention rate of 98%, a working condition is 20˜25° C. , a working pressure is 6.5˜8.0 bar, and a membrane flux is 26 ml/cm 2 . [0000] TABLE 5 Measured No. Item Unit value 1 COD Cr mg/L 10 2 SS mg/L 18 3 turbidity NTU 1 4 chromaticity 18 5 pH 7.7 6 Hardness mmol/l [0000] TABLE 6 Measured No. Item Unit value 1 COD Cr mg/L 75 2 SS mg/L 50 3 turbidity NTU 2.6 4 saltness ‰ 11.5 5 pH 8.2 6 conductivity μS/cm 11200 Example 3 [0065] A process for purifying deeply treating printing and dyeing wastewater of 6,000 tons per day and reusing recycled water. [0066] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 7. [0000] TABLE 7 Measured No. Item Unit value 1 COD Cr mg/L 391 2 SS mg/L 190 3 turbidity NTU 8.4 4 saltness 0.9 5 pH 7.7 6 conductivity μS/cm 8100 [0067] The deeply treating printing and dyeing wastewater is drawn via the first pump 12 for 300 T/H. A first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 100 T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 75 T/H, wherein the deeply treating printing and dyeing wastewater is 100 T/H, the concentrated liquid after reflowing for catalytic microelectrolysis for 25 T/H, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 200 T/H via the T-cock, a pipe and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater. [0068] The deeply treating printing and dyeing wastewater has low saltness. A working voltage of the nanometer catalytic microelectrolysis is 16˜18 V, a current intensity is 3760˜3800A. A first part of the deeply treating printing and dyeing wastewater after catalytic microelectrolysis to produce nascent state chlorine flows into the neutralization tank 16 via a first one-way valve 15 for 100 T/H, and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 200 T/H via a pipe and a second one-way valve 14 . The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater. A measured SDI is 4.5. [0069] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 to obtain the dialyzed liquid and the concentrated liquid, the dialyzed liquid is stored in the dialyzed liquid storage tank 28 via the first valve 26 , the T-cock, and the second valve 27 for 195 T/H, and supplies water to a clean water storage tank 32 via the T-cock and the third stop valve 31 . The concentrated liquid has a first part reflowing to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 90 T/H, a second part reflowing into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 100 T/H, and a third part drained for 105 T/H. [0070] A reverse osmosis membrane of the reverse osmosis membrane filtration system 25 , is a reverse osmosis rolling membrane having NaCl retention rate of 98%, a working condition is 18˜21° C., a working pressure is 15˜17 bar, and a membrane flux is 20 ml/cm 2 . The recycled rate of the wastewater is 65%, qualities of the recycled water are shown in Table 8, and indexes of the concentrated liquid are shown in Table 9. [0000] TABLE 8 Measured No. Item Unit value 1 COD Cr mg/L 9 2 SS mg/L 15 3 turbidity NTU 0.7 4 chromaticity 13 5 pH 6.9 6 conductivity μS/cm 8 [0000] TABLE 9 Measured No. Item Unit value 1 COD Cr mg/L 83 2 SS mg/L 55 3 turbidity NTU 3 4 chromaticity 30 5 saltness ‰ 2.7 6 pH 8.5 7 conductivity μS/cm 6500 Example 4 [0071] A process for purifying deeply treating printing and dyeing wastewater of 20,000 tons per day and reusing recycled water. [0072] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 10. [0073] The deeply treating printing and dyeing wastewater is drawn via the first pump 12 for 1000 T/H. A first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 250 T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 360 T/H, wherein the deeply treating printing and dyeing wastewater is 250 T/H, the concentrated liquid after reflowing for catalytic microelectrolysis for 110 T/H, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 750 T/H via the T-cock, a pipe and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater. [0000] TABLE 10 Measured No. Item Unit value 1 COD Cr mg/L 155 2 SS mg/L 182 3 turbidity NTU 6.5 4 chromaticity 1.5 5 pH 7.7 6 conductivity μS/cm 6900 [0074] Due to low saltness of the deeply treating printing and dyeing wastewater, industrial NaCl is added to increase the saltness up to 9.5 0 / 00 , and then nanometer catalytic microelectrolysis is processed. A working voltage of the nanometer catalytic microelectrolysis is 6˜7 V, a current intensity is 4950˜5000 A. The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater. A measured SDI is 2.6. [0075] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 to obtain the dialyzed liquid and the concentrated liquid, flowing speeds of the dialyzed liquid and the concentrated liquid are respectively 400.00 T/H and 860.00 T/H. The concentrated liquid reflows to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 150.00 T/H, reflows into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 110.00 T/H, and drains the rest for 140.00 T/H. The recycled rate of the wastewater is 86%, qualities of the recycled water are shown in Table 11, and indexes of the concentrated liquid are shown in Table 12. [0000] TABLE 11 Measured No. Item Unit value 1 COD Cr mg/L 9 2 SS mg/L 20 3 turbidity NTU 0.9 4 chromaticity 13 5 pH 7.4 6 Hardness mmol/l [0000] TABLE 12 Measured No. Item Unit value 1 COD Cr mg/L 95 2 SS mg/L 39 3 turbidity NTU 1.9 4 saltness ‰ 11.5 5 pH 8.2 6 conductivity μS/cm 9200 [0076] A nanofiltration membrane of the nanofiltration membrane filtration and separation system, is a nanofiltration rolling membrane having MgSO 4 retention rate of 98%, a working condition is 20∞45° C. , a working pressure is 6.5˜15.0 bar, and a membrane flux is 29 ml/cm 2 .
A purifying device and a process for deeply treating printing and dyeing wastewater are provided. The device includes a nanometer catalytic microelectrolysis system, a membrane filtration and separation system and a a membrane washing regeneration system. The method includes the following steps of: drawing the printing and dyeing wastewater by a first water pump ( 12 ), pumping a first part of the wastewater into a nanometer catalytic microelectrolysis tank ( 13 ) to perform catalysis microelectrolysis, and a second part of the wastewater into a neutralization tank ( 16 ) to mix with the water from the nanometer catalytic microelectrolysis tank ( 13 ) to precipitate, filtering the wastewater by a sand filtration tank ( 17 ), and then pumping the wastewater into an adsorption and filteration device of granular active carbon ( 18 ) for adsorption and filtration. The process has lower cost and higher energy efficiency, and can realize recycled water to be reused.
Identify the most important claim in the given context and summarize it
[ "BACKGROUND OF THE PRESENT INVENTION [0001] 1.", "Field of Invention [0002] The present invention relates to a process for purifying and recycling printing and dyeing wastewater, and more particularly to a purifying and recycling process for deeply treating printing and dyeing wastewater based on a combination of nanometer catalytic microelectrolysis technology and membrane technology.", "[0003] 2.", "Description of Related Arts [0004] Textile industry generally includes spinning, printing and dyeing, chemical fiber, clothing and manufacture of textile devices.", "With the fast development of the economy, the printing and dyeing industry also enters a fast developing period, the devices and technology are improved obviously, the production process and devices are changed continuously, and the printing and dyeing companies develop very fast.", "So far, there are more than 2,000 printing and dyeing companies above designated size in China.", "The printing and dyeing processes refer to physical and chemical process to various textile material fibers, yarns, and cloths in production, and include pre-treating, dyeing, printing, and after-treating of textile materials which are together called printing and dyeing processes.", "At present, the development of the textile technology is guided with ecological fabrics production and green production technology, catches the source through multi-channels including processes, adjuvants, and devices, emphasizes the ecological problems of each link, optimizes the textile processes hard, and reduces the consumption of chemical agents, water and energy, so as to achieve the goal of high efficiency, high speed and environment-friendliness.", "A great effort is paid to environment-friendly dye stuff adjuvants, new processes saving water, energy and reducing emission and new devices at home and abroad, and an obvious progress is made in printing and dyeing technology with no water or less water, printing and dyeing of painting, and utility model of textile saving energy and water.", "However, despite the fast development of the technology of saving water and treating wastewater in the textile printing and dyeing industry, the textile printing and dyeing wastewater is still an important pollution source in China's industrial system.", "According to the statistics of Ministry of Environmental Protection of the People's Republic of China, the printing and dyeing wastewater drained by the printing and dyeing industry is the fifth largest in all the industrial departments of China.", "The character of the printing and dyeing wastewater as an important environment pollution source is firstly large amount.", "At present, the printing and dyeing products are about 800,000˜900,000 tons in the world, and China has 150,000 tons, ranking in the top.", "About 10%˜15% of the printing and dyeing components are drained into the environment along with wastewater in production and use of the printing and dyeing products.", "The printing and dyeing industry and textile printing and dyeing industry are high developed, and the printing and dyeing wastewater pollutes the environment more seriously.", "In 2004, the printing and dyeing industry drained 1.36 billions m 3 , and the pollutant is the sixth largest in all the industrial departments calculated by COD.", "Secondly, the type of printing and dyeing components as environmental pollutants have many species and complex structures.", "The synthesis printing and dyeing components have more than 30,000 species, and more than 80% of them contain complex organic compounds of azo bond and poly-aromatic.", "Printing and dyeing industry is one of the industries of extremely serious environmental pollution in the chemical industries.", "The printing and dyeing wastewater has large chromaticity, high concentration of organic matters, complex components, many hardly biodegradable substances, and contains a large number of inorganic salts, sulfides, etc.", ", are intractable industrial wastewater.", "The printing and dyeing components are hard to be removed due to its complex aromatic hydrocarbons molecular structure, which are desired to exist stably in water environment or under illumination and oxidants when designing and production.", "Thirdly, most printing and dyeing components are toxic non-degradable organic matters having strong chemical stabilization, and carcinogenic, teratogenic and mutagenic effects.", "Even the concentration of the remained printing and dyeing components are low in the wastewater, it will also reduce the light transmittance of water body after draining into the water body, so as to cause damage to the water ecological system.", "Therefore, efficiently treating the printing and dyeing wastewater has become an important problem.", "[0005] The printing and dyeing wastewater has characters such as high concentration and large number of species of pollutants, containing toxic and harmful components and high chromaticity.", "The ordinary treating methods to the printing and dyeing wastewater at home and abroad comprise physical methods, chemical methods, biological methods, and etc.", "[0006] 1.", "Physical Methods [0007] The physical methods mainly comprise flotation method of adsorption, membrane separation method, ultrasonic gas vibration method, and distillation method.", "The adsorption method is applied mostly in the physical methods.", "At present, the activated carbon adsorption method is mainly adopted in international.", "The method is very effective for removal of dissolved organic matters, but can not remove colloids and hydrophobic dyeing, and has good adsorption properties to the water-soluble printing and dyeing components in cationic printing and dyeing, direct printing and dyeing, acid printing and dyeing, reactive printing and dyeing.", "[0008] Adsorption flotation method first absorbs printing and dyeing ion and other soluble substances from the wastewater with highly dispersed powdery inorganic adsorbents such as bentonite and kaolin, then adds the flotation agent to obtain hydrophobic particles by airfloating, the removal efficiency of acid printing and dyeing, cationic printing and dyeing, and direct printing and dyeing can be more than 92%.", "[0009] The membrane technology applied in treating printing and dyeing wastewater mainly comprises ultra-filtraten and reverse osmosis.", "The ultra-filtraten technology has a decolourization rate of 80%˜97%, and a TOC removal rate of 60%˜85% in treating scattered printing and dyeing wastewater.", "The reverse osmosis technology has a removal rate of soluble solid of 85%˜-99%, and an average recycle rate of 75%˜85%.", "[0010] The ultrasonic technology can become an effective method of treating wastewater by controlling the ultrasonic frequency and saturation of gas.", "The Zhangjiagang Jiuzhou Fine Chemical Industry treats printing and dyeing wastewater with the FBZ wastewater treatment equipment designed according to ultrasonic gas vibration technology, and has an average chroma removal rate of 97%, a COD Cr removal rate of 90.6%, and a total pollution load reduction rate of 85.9%.", "[0011] 2.", "Chemical Methods [0012] Chemical methods mainly comprise chemical coagulation method, chemical oxidation method, photochemical catalytic oxidation method, and electrochemical method.", "The chemical coagulation method is a frequently used method of treating printing and dyeing wastewater, and was thought to be one of the most efficient and economic decoloring technologies.", "The chemical oxidation method is a main method of decoloring printing and dyeing wastewater, decolors by destroying printing and dyeing color groups with various oxidation methods.", "Depending on the oxidants and oxidation condition, the chemical oxidation method is divided into ozone oxidation method and deep oxidation method.", "Furthermore, the photochemical catalytic oxidation method as a deep oxidation technology for reducing organic matters develops fast in recent years.", "Referring to ZHANG Gui-Ian, Photodegradation of dyes in water using rotation reactor [J].", "JOURNAL OF TEXTILE RESEARCH, 2005, 26(3): 109-111, the photochemical catalytic oxidation method achieves good decoloring effect in degrading printing and dyeing wastewater.", "The electrochemical method purifies printing and dyeing wastewater by electrode reaction.", "[0013] Microelectrolysis method is an electrochemical technology using iron and carbon filler corroded in the electrolyte solution to form numerous tiny primary cells to treat wastewater.", "It is a wastewater treating method combining electrolysis, coagulation, electrolytic flocculation, adsorption and other physical and chemical effects in one.", "In the treatment of printing and dyeing wastewater, printing and dyeing molecules are first adsorbed onto the carbon surface, and have oxidation or reduction reactions in the two poles.", "The electrode can also be used for electrolysis.", "Referring to Jia Jinping, Shen Zhemin, Wang Wenhua, The Status Quo and Progress on Treating Methods of Wastewater Containing Dyestaff, 2000, 191:26-29, the integrated performance of electrode conductivity, adsorption, catalytic, redox, the flotation of activated carbon fiber electrode is used to achieve a one-stop process of adsorption—electrode reaction—flocculation and desorption, and the decolorization rate is 98%, COD Cr removal rate is greater than 80%.", "Referring to YAN Bin, FU Hai-yan, CHAI Tian, JIN Lei, SHI Qian, Application of Microelectrolysis Method in Dyehouse Wastewater Treatment, JOURNAL OF XIAMEN UNIVERSITY OF TECHNOLOGY, 2008, 16(1):18-22, decoloring and COD Cr removal effects to wastewater produced by cotton series and chemical fiber synthetic woven fabrics with microelectrolysis technology of iron—carbon electrode is studied, when the mass ratio of iron to carbon is 2:1, HRT is 1.5 h, the COD removal rate is up to 55%, chromaticity removal rate is 95%, BOD/COD increased from 0.3 to 0.5.", "Referring to Luo Jingsheng, Zeng Kangmei, Zuo Jingying, Li Xin, Liu Fude, TREATMENT OF DYE WASTEWATER BY MICROELECTROLYSIS PROCESS, TECHNOLOGY OF WATER TREATMENT, 2005, 31(11):67-70, treating production wastewater containing dyestuff, dye intermediate, and adjuvant with circulating iron—carbon microelectrolysis method is studied.", "The result shows that pH of the raw water has great affect to treating effect.", "When pH is within 1˜5, the lower pH is, the better the treating effect is, and when pH is 1, COD removal rate is about 60%, chromaticity removal rate is above 94%.", "Referring to Deng Xihong, Wang Chao, An Engineering Example of Treating Dyeing Wasterwater Using Microelectrolysis—Physical and Chemical—Biochemical Method, Environmental Science and Management, 2008, 33(3):120-122, the printing and dyeing wastewater of high pollutant concentration, large concentration fluctuations, alkaline, high chromaticity, and biorefractory property is treated with Microelectrolysis—Physical and Chemical—Biochemical Method, which runs continuously for three months, and the result shows that the method runs stably, has low investment and low treating cost, (0.765 RMB per ton), the removal rates of COD, BOD, SS and chromaticity are respectively above 94%, 96%, 89%, and 96%.", "The indexes of effluent quality all meet emission standards.", "EpolitoW illiam J,HanbaeYang, et al.", "studies microelectrolysis to RB4 (Reactive Blue4) wastewater.", "The experimental result shows that the decoloring rate gradually increases with the decreasing of pH, and increasing of stirring, experimental temperature and ionic strength.", "There are also many other reports about treating printing and dyeing wastewater with electrochemical method.", "[0014] 3.", "Biochemical Methods [0015] The printing and dyeing wastewater is biorefractory, so if desiring treating with biochemical methods, MLSS of the activated sludge can be increased, and biochemical performance of the activated sludge can be improved, or efficient strains are used to increase biochemical effect.", "Breeding and training excellent decolorization flora is an important development direction of the biochemical methods.", "The research of formation of engineering bacteria with multiple plasmids efficiently decoloring printing and dyeing wastewater by use of mutation breeding, protoplast fusion, and genetic engineering techniques.", "The recent studies show that the dominant bacteria of the Pseudomonas bacteria, Sphaerotilus natans, Arthrobacter, Bacillus subtilis, and oxidative yeast have a considerable effect of in degradation of printing and dyeing wastewater.", "[0016] In recent years, the combination of chemical and physical methods for treating printing and dyeing wastewater, or the combination of biological treatment and physical treatment for printing and dyeing wastewater has developed rapidly.", "Chinese patent of ZL 200710008643.0 discloses a treating method for printing and dyeing wastewater based on membrane technology, which combines chemical coagulation and sedimentation, biological treatment, and reverse osmosis separation technology for treating combines printing and dyeing wastewater.", "[0017] Although the above methods all have good treating effect, the following problems still exist.", "[0018] In the physical and chemical aspect, activated carbon has good adsorption effect, but activated carbon is difficult to regenerate, has high cost, and thus its application is limited.", "Many companies turn to other adsorbent of cheaper and easy-to-get materials.", "Electrolysis method and oxidation method has certain effect in removing chromaticity of printing and dyeing wastewater, but COD removal is often not satisfactory, the cost of the treatment agents is relatively high.", "Many new means of oxidation are still in the research phase, and have not being industrialized.", "[0019] In biochemical aspect, printing and dyeing products are typical fine chemical products, with characteristics of small volume and numerous varieties, and its structure is complex, production process is long, operations of nitration, condensation, reduction, oxidation, diazotization, and coupling are often accompanied from raw materials to finished products.", "By-products are many, production yield is low, wastewater has complex organic composition, chemical reaction of printing and dyeing production, and processes of separation, refining, and washing all use water as solvent, and thus water consumption is large.", "Biochemical treatment of printing and dyeing wastewater has the advantages of less investment, but there are still disadvantages that micro-organisms are difficult to adapt to printing and dyeing wastewater, water quality is volatile, and toxicity is big.", "And problems of sludge disposal, anaerobic biogas processing and complex management also exist.", "In addition, although the iron-carbon microelectrolysis electrode made some progress in the treatment of printing and dyeing wastewater, the consumption of iron-carbon produces a lot of precipitation, so that treated wastewater is difficult to use, only to meet emission standards.", "[0020] The treatment of printing and dyeing wastewater using a single method is often difficult to achieve the desired results.", "The conventional method is to combines each treating methods, which has drawbacks of long process, high operating cost, and unstable water quality.", "The treated wastewater ordinarily reaches to the emission standard II.", "The discharged wastewater are processed with a variety of methods of biochemical, chemical, and physical and chemical treatment, so the physical and chemical properties are very stable, any following decolorizing purification becomes very difficult, and general methods are difficult to further decolor or purify the wastewater.", "The deeply treated wastewater reaching emission standard II will have long-term impact on the environment.", "On the other hand, the current fresh water resources are increasingly lacking, and water supply has become increasing problem.", "If deeply treated printing and dyeing wastewater can be reused as recycled water, it will not only significantly reduce the impact on the environment, but also save a lot of fresh water resources.", "SUMMARY OF THE PRESENT INVENTION [0021] An object of the present invention is to provide a purifying device for deeply treating printing and dyeing wastewater, based on a combination of nanometer catalytic microelectrolysis technology membrane technology, and conventional treating technology, has low cost, high efficiency and obtaining recycled water, with respect to existing problems of high cost, low efficiency and water waste in conventional treating methods for printing and dyeing wastewater, and a purifying process therefor.", "[0022] The deeply treated printing and dyeing wastewater according to the present invention refers to printing and dyeing wastewater reaching emission standard II after pre-treatment.", "The printing and dyeing wastewater reaching emission standard II after pre-treatment can be printing and dyeing wastewater reaching emission standard II after treatment by at least one method of biochemical method, chemical method, physical and chemical method.", "[0023] A purifying device for deeply treating printing and dyeing wastewater according to the present invention comprises: [0024] a nanometer catalytic microelectrolysis system, for processing steps of nanometer catalytic microelectrolysis, neutralization precipitation, crude filteration and adsorption and filteration of activated carbon, comprising: a first stop valve, a first pump, a nanometer catalytic microelectrolysis tank, a neutralization tank, a sand filteration tank and an adsorption and filteration device of granular active carbon, wherein an inlet of the first stop valve is connected externally to an outlet of printing and dyeing wastewater, an inlet of the first pump is connected with an outlet of the first stop valve, an outlet of the first pump is connected with an inlet of the nanometer catalytic microelectrolysis tank and an inlet of the neutralization tank, an outlet of the nanometer catalytic microelectrolysis tank is connected with the inlet of the neutralization tank via a one-way valve, an inlet of the sand filteration tank is connected with an outlet of the neutralization tank, and an inlet of the adsorption and filteration device of granular active carbon is connected with an outlet of the sand filteration tank;", "[0025] a membrane filtration and separation system, for filtering and separating the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis to obtain dialyzed liquid and concentrated liquid, comprising: a second stop valve, a second pump, a security filter, a high-pressure pump, a reverse osmosis filtration membrane system and a dialyzed liquid storage tank, wherein the membrane filtration and separation system pumps the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis into the membrane filtration and separation system with the high-pressure pump after being filtered by the security filter, the dialyzed liquid and the concentrated liquid are obtained by separating with membrane filtering, the dialyzed liquid enters into the dialyzed liquid storage tank to be recycled water, the concentrated liquid has a first part reflowing to be processed by circulated membrane filtration and separation, a second part reflowing into the step of nanometer catalytic microelectrolysis to be reused, and a rest part drained, wherein an inlet of the second stop valve is connected with the outlet of purified wastewater of the adsorption and filteration device of granular active carbon, an outlet of the second stop valve is connected with the reverse osmosis filtration membrane system via the second pump, the security filter, and the high-pressure pump in turn, and a dialyzed liquid outlet of the reverse osmosis filtration membrane system is connected with an inlet of the dialyzed liquid storage tank via a first valve;", "and [0026] a membrane washing regeneration system, for washing the membrane filtration and separation system, comprising a washing liquid tank and a communication pipe, wherein an inlet of the washing liquid tank is connected with an outlet of the dialyzed liquid storage tank via a third stop valve and a second valve, a first outlet of the washing liquid tank is connected with the reverse osmosis filtration membrane system via the second valve and the third stop valve, a second outlet of the washing liquid tank is connected with the security filter via the second valve, the third stop valve and the second pump, and a third outlet of the washing liquid tank is connected with the dialyzed liquid storage tank via the second valve, a first concentrated liquid outlet of the reverse osmosis filtration membrane system reflows to be connected with an inlet of the high-pressure pump via the third stop valve, a second concentrated liquid outlet of the reverse osmosis filtration membrane system reflows to be connected with the nanometer catalytic microelectrolysis tank via the third stop valve to be reused.", "[0027] A purifying process for deeply treating printing and dyeing wastewater according to the present invention comprises: [0028] after pumping the printing and dyeing wastewater with the pump, feeding a first part of the printing and dyeing wastewater into the nanometer catalytic microelectrolysis tank to be processed by catalytic microelectrolysis, and then into the neutralization tank, feeding a second part of the printing and dyeing wastewater directly into the neutralization tank to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation, filtering by the crude filter tank, and then pumping into the adsorption and filteration device of granular active carbon to be adsorbed and filtered, so as to remove chlorine and solid impurity produced by microelectrolysis, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater, wherein SDI thereof should be less than 5.", "[0029] A working voltage of the nanometer catalytic microelectrolysis is 2˜18 V, preferably 4˜10 V, a current intensity is 5˜5000 A, preferably 50˜1000 A. The deeply treated printing and dyeing wastewater containing NaCl flows into the neutralization tank via a one-way valve after producing nascent state chlorine by microelectrolysis.", "The second part of the printing and dyeing wastewater directly enters into the neutralization tank via a pipe and the one-way valve.", "Nanometer catalytic microelectrolysis has the following advantages.", "(1) The nascent state chlorine produced by nanometer catalytic microelectrolysis kills microorganism in the wastewater, and reduces live bodies of microorganism to be less than 30/ml, so as to eliminate pollution of the membrane materials.", "(2) Organic matters in the wastewater are oxidated and degraded, remaining dyestuff is degraded and decolored, and COD Cr is reduced.", "(3) The wastewater is purified by crude filtering and fine filtering relatively big coagulation of suspended matter and colloid in the wastewater under effect of electric field.", "(4) Heavy metal ions in the wastewater move towards a negative pole of the nanometer catalytic microelectrolysis tank and form precipitate thereon, so as to reduce heavy metal ions in the wastewater.", "[0030] The deeply treated wastewater still has deep color and higher COD Cr after being treated by multiple processing of biochemical, chemical, physical and chemical methods, and ordinary chemical treatment is very difficult to further decolorize and decrease COD Cr .", "In the natural environment, even after several days, the wastewater will not fade.", "Treating the deeply treated wastewater with nanometer catalytic microelectrolysis can decolor the wastewater and significantly reduce COD Cr within 2 to 5 minutes.", "[0031] A concentration of NaCl of the printing and dyeing wastewater is 6 0 / 00 ˜50 0 / 00 , preferably 0.6 0 / 00 ˜1.3 0 / 00 , and can be increased to 6 0 / 00 ˜50 0 / 00 with industrial NaCl when low.", "[0032] The step of nanometer catalytic microelectrolysis produces nascent state chlorine by nanometer catalytic microelectrolysis of ⅓ to ⅕ of the deeply treated printing and dyeing wastewater, so as to oxidate and degrade organic matters in the wastewater kill microorganism in the wastewater, and produce coagulation of suspended matter, colloid, and charged corpuscle in the wastewater to form relatively larger particles under effect of electric field.", "[0033] The step of neutralization precipitation mixes the wastewater treated with nanometer catalytic microelectrolysis, which contains nascent state chlorine, with the rest ⅔ to ⅘ of the deeply treated printing and dyeing wastewater not treated with nanometer catalytic microelectrolysis, the nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater and kills the microorganism in the wastewater.", "Crystal nucleus produced by coagulation of microelectrolysis precipitates the suspended matter, solid particles, and colloid.", "[0034] The crude filteration is one selected from the group consisting of sand filteration, and multi-media filteration.", "[0035] The membrane filtration and separation system is one selected from the group consisting of a reverse osmosis membrane filtration and separation system, and a nanofiltration membrane filtration and separation system.", "[0036] A reverse osmosis membrane of the reverse osmosis membrane filtration system, is a reverse osmosis membrane having NaCl retention rate of 98%, a membrane structure is rolling membrane module or a tubular membrane module, a working condition is from room temperature to 45° C., and a working pressure is 7˜25 bar.", "[0037] A nanofiltration membrane of the nanofiltration membrane filtration and separation system, is a nanofiltration membrane having MgSO 4 retention rate of 98%, a membrane structure is rolling membrane module or a tubular membrane module, a working condition is from room temperature to 45° C., and a working pressure is 3˜20 bar.", "[0038] The present invention not only overcomes the defects of high cost by single-use of the membrane filtration and separation process, or adsorption process, but also overcomes the defects of unsatisfying treating effect of conventional methods of treating printing and dyeing wastewater and polluting the environment by the drained wastewater, turning the decayed into wonder, and using the waste as a resource by purifying existing deeply treated printing and dyeing wastewater and recycling to reuse.", "Compared with prior art, The present invention has the following outstanding advantages of: [0039] 1.", "fast degrading remaining dyestuff of the deeply treated printing and dyeing wastewater to eliminate the color thereof within 2 to 5 minutes;", "[0040] 2.", "low investment;", "[0041] 3.", "deep treating degree, so that pollution is greatly reduced;", "[0042] 4, low cost, and large economic efficiency;", "[0043] 5, high utilization of water resources;", "and [0044] 6, greatly reducing discharge of wastewater.", "BRIEF DESCRIPTION OF THE DRAWINGS [0045] The FIGURE is a sketch view of a structure of a purifying device for deeply treating printing and dyeing wastewater according to a preferred embodiment of the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0046] The present invention finishes a designing of a process for purifying deeply treating printing and dyeing wastewater and reusing recycled water after deep and systematic comparative study of composition and property of the existing deeply treating printing and dyeing wastewater, and conventional treating processes.", "The present invention provides a process especially adapted for purifying deeply treating printing and dyeing wastewater and reusing recycled water by combining methods of nanometer catalytic microelectrolysis, neutralization, crude filteration, adsorption and filteration of activated carbon, and membrane filtration.", "[0047] A preferred embodiment of the present invention describing detailedly is as follows accompanying with the FIGURE.", "[0048] Referring to the FIGURE, a purifying device for deeply treating printing and dyeing wastewater according to a preferred embodiment of the present invention, comprising: [0049] a nanometer catalytic microelectrolysis system, for processing steps of nanometer catalytic microelectrolysis, neutralization precipitation, crude filteration and adsorption and filteration of activated carbon, comprising: a first stop valve 11 , a first pump 12 , a nanometer catalytic microelectrolysis tank 13 , a neutralization tank 16 , a sand filteration tank 17 and an adsorption and filteration device of granular active carbon 18 , wherein an inlet of the first stop valve 11 is connected externally to an outlet of printing and dyeing wastewater, an inlet of the first pump 12 is connected with an outlet of the first stop valve 11 , an outlet of the first pump 12 is connected with an inlet of the nanometer catalytic microelectrolysis tank 13 and an inlet of the neutralization tank 16 , an outlet of the nanometer catalytic microelectrolysis tank 13 is connected with the inlet of the neutralization tank 16 via a one-way valve, an inlet of the sand filteration tank 17 is connected with an outlet of the neutralization tank 16 , and an inlet of the adsorption and filteration device of granular active carbon 18 is connected with an outlet of the sand filteration tank 17 ;", "[0050] a membrane filtration and separation system, for filtering and separating the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis to obtain dialyzed liquid and concentrated liquid, comprising: a second stop valve 21 , a second pump 22 , a security filter 23 , a high-pressure pump 24 , a reverse osmosis filtration membrane system 25 , a first valve 26 , a second valve 27 , and a dialyzed liquid storage tank 28 , wherein the membrane filtration and separation system pumps the printing and dyeing wastewater purified by the nanometer catalytic microelectrolysis into the membrane filtration and separation system with the high-pressure pump 24 after being filtered by the security filter 23 , the dialyzed liquid and concentrated liquid are obtained by separating with membrane filtering, the dialyzed liquid enters into the dialyzed liquid storage tank 28 to be recycled water, the concentrated liquid has a first part reflowing to be processed by circulated membrane filtration and separation, a second part reflowing into the step of nanometer catalytic microelectrolysis to be reused, and a rest part drained, wherein an inlet of the second stop valve 21 is connected with the outlet of purified wastewater of the adsorption and filteration device of granular active carbon 18 , an outlet of the second stop valve 21 is connected with the reverse osmosis filtration membrane system 25 via the second pump 22 , the security filter 23 , and the high-pressure pump 24 in turn, and a dialyzed liquid outlet of the reverse osmosis filtration membrane system 25 is connected with an inlet of the dialyzed liquid storage tank 28 via the first valve 26 and the second valve 27 ;", "and [0051] a membrane washing regeneration system, for washing the membrane filtration and separation system, comprising: a third stop valve 31 , a washing liquid tank 32 , a third valve 33 , a fourth valve 34 , a fifth valve 35 , a fourth stop valve 36 , a fifth stop valve 37 , a sixth stop valve 38 , a seventh stop valve 39 , and a communication pipe, wherein an inlet of the washing liquid tank 32 is connected with an outlet of the dialyzed liquid storage tank 28 via a third stop valve 31 and a second valve 27 , a first outlet of the washing liquid tank 28 is connected with the reverse osmosis filtration membrane system 25 via the third valve 33 and the fourth stop valve 36 , a second outlet of the washing liquid tank 32 is connected with the security filter 25 via the fourth valve 34 , the sixth stop valve 38 and the second pump 22 , and a third outlet of the washing liquid tank 32 is connected with the dialyzed liquid storage tank 28 via the fifth valve 35 and the second valve 27 , a first concentrated liquid outlet of the reverse osmosis filtration membrane system 25 reflows to be connected with an inlet of the high-pressure pump 24 via the fourth stop valve 36 and the fifth stop valve 37 , a second concentrated liquid outlet of the reverse osmosis filtration membrane system 25 reflows to be connected with the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused.", "[0052] A purifying process for printing and dyeing wastewater of a purifying device for deeply treating printing and dyeing wastewater according to a preferred embodiment of the present invention in the FIGURE is shown as follows.", "Example 1 [0053] A process for purifying deeply treating printing and dyeing wastewater of 150 tons per day and reusing recycled water.", "[0054] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 1.", "[0000] TABLE 1 Measured No. Item Unit value 1 COD Cr mg/L 156 2 SS mg/L 110 3 turbidity NTU 6 4 chromaticity 80 5 saltness ‰ 6.6 6 pH 8.3 7 conductivity μS/cm 7200 [0055] The deeply treating printing and dyeing wastewater of 150 tons per day is drawn via the first pump 12 for 7.5T/H.", "At the beginning, a first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 1.5T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 2.8T/H, after catalytic microelectrolysis, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 6.0T/H via the T-cock and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater.", "[0056] A working voltage of the nanometer catalytic microelectrolysis is 8˜9V, a current intensity is 500˜510 A. The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater.", "A measured SDI is 2.5.", "[0057] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 , the dialyzed liquid is stored in the dialyzed liquid storage tank 28 via the first valve 26 , the T-cock, and the second valve 27 , and supplies water to a clean water storage tank 32 via the T-cock and the third stop valve 31 .", "[0058] A reverse osmosis membrane of the reverse osmosis membrane filtration system 25 , is a reverse osmosis rolling membrane having NaCl retention rate of 98%, a working condition is 32˜35° C., a working pressure is 9·12 bar, a membrane flux is 20 ml/cm 2 , flowing speeds of the dialyzed liquid and the concentrated liquid are respectively 5.3T/H and 4.9T/H, the concentrated liquid reflows to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 1.4 T/H, reflows into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 1.3 T/H, and drains the rest for 2.6 T/H.", "The recycled rate of the wastewater is 65%, qualities of the recycled water are shown in Table 2, and indexes of the concentrated liquid is shown in Table 3.", "[0000] TABLE 2 Measured No. Item Unit value 1 COD Cr mg/L 9 2 SS mg/L 15 3 turbidity NTU 0.8 4 chromaticity 15 5 pH 6.7 6 conductivity μS/cm 10 [0000] TABLE 3 Measured No. Item Unit value 1 COD Cr mg/L 156 2 SS mg/L 50 3 turbidity NTU 2 4 chromaticity 30 5 saltness ‰ 3.7 6 pH 8.5 7 conductivity μS/cm 9100 Example 2 [0059] A process for purifying deeply treating printing and dyeing wastewater of 3,000 tons per day and reusing recycled water.", "[0060] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 4.", "[0000] TABLE 4 Measured No. Item Unit value 1 COD Cr mg/L 181 2 SS mg/L 160 3 turbidity NTU 7.5 4 chromaticity 13 5 pH 7.6 6 conductivity μS/cm 6000 [0061] The deeply treating printing and dyeing wastewater is drawn via the first pump 12 for 150 T/H.", "A first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 50 T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 75 T/H, wherein the deeply treating printing and dyeing wastewater is 50 T/H, the concentrated liquid after reflowing for catalytic microelectrolysis for 25 T/H, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 100 T/H via the T-cock, a pipe and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater.", "[0062] Due to low saltness of the deeply treating printing and dyeing wastewater, industrial NaCl is added to increase the saltness up to 12.5%, and then nanometer catalytic microelectrolysis is processed.", "A working voltage of the nanometer catalytic microelectrolysis is 5˜6 V, a current intensity is 1560˜1580 A. The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater.", "A measured SDI is 2.9.", "[0063] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 to obtain the dialyzed liquid and the concentrated liquid, flowing speeds of the dialyzed liquid and the concentrated liquid are respectively 73.5 T/H and 127.5T/H, the dialyzed liquid is stored in the dialyzed liquid storage tank 28 via the first valve 26 , the T-cock, and the second valve 27 for 127.5T/H, and supplies water to a clean water storage tank 32 via the T-cock and the third stop valve 31 .", "The concentrated liquid reflows to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 26 T/H, reflows into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 25.0 T/H, and drains the rest for 22.5 T/H.", "The recycled rate of the wastewater is 85%, qualities of the recycled water are shown in Table 5, and indexes of the concentrated liquid are shown in Table 6.", "[0064] A nanofiltration membrane of the nanofiltration membrane filtration and separation system, is a nanofiltration rolling membrane having MgSO 4 retention rate of 98%, a working condition is 20˜25° C. , a working pressure is 6.5˜8.0 bar, and a membrane flux is 26 ml/cm 2 .", "[0000] TABLE 5 Measured No. Item Unit value 1 COD Cr mg/L 10 2 SS mg/L 18 3 turbidity NTU 1 4 chromaticity 18 5 pH 7.7 6 Hardness mmol/l [0000] TABLE 6 Measured No. Item Unit value 1 COD Cr mg/L 75 2 SS mg/L 50 3 turbidity NTU 2.6 4 saltness ‰ 11.5 5 pH 8.2 6 conductivity μS/cm 11200 Example 3 [0065] A process for purifying deeply treating printing and dyeing wastewater of 6,000 tons per day and reusing recycled water.", "[0066] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 7.", "[0000] TABLE 7 Measured No. Item Unit value 1 COD Cr mg/L 391 2 SS mg/L 190 3 turbidity NTU 8.4 4 saltness 0.9 5 pH 7.7 6 conductivity μS/cm 8100 [0067] The deeply treating printing and dyeing wastewater is drawn via the first pump 12 for 300 T/H.", "A first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 100 T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 75 T/H, wherein the deeply treating printing and dyeing wastewater is 100 T/H, the concentrated liquid after reflowing for catalytic microelectrolysis for 25 T/H, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 200 T/H via the T-cock, a pipe and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater.", "[0068] The deeply treating printing and dyeing wastewater has low saltness.", "A working voltage of the nanometer catalytic microelectrolysis is 16˜18 V, a current intensity is 3760˜3800A.", "A first part of the deeply treating printing and dyeing wastewater after catalytic microelectrolysis to produce nascent state chlorine flows into the neutralization tank 16 via a first one-way valve 15 for 100 T/H, and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 200 T/H via a pipe and a second one-way valve 14 .", "The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater.", "A measured SDI is 4.5.", "[0069] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 to obtain the dialyzed liquid and the concentrated liquid, the dialyzed liquid is stored in the dialyzed liquid storage tank 28 via the first valve 26 , the T-cock, and the second valve 27 for 195 T/H, and supplies water to a clean water storage tank 32 via the T-cock and the third stop valve 31 .", "The concentrated liquid has a first part reflowing to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 90 T/H, a second part reflowing into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 100 T/H, and a third part drained for 105 T/H.", "[0070] A reverse osmosis membrane of the reverse osmosis membrane filtration system 25 , is a reverse osmosis rolling membrane having NaCl retention rate of 98%, a working condition is 18˜21° C., a working pressure is 15˜17 bar, and a membrane flux is 20 ml/cm 2 .", "The recycled rate of the wastewater is 65%, qualities of the recycled water are shown in Table 8, and indexes of the concentrated liquid are shown in Table 9.", "[0000] TABLE 8 Measured No. Item Unit value 1 COD Cr mg/L 9 2 SS mg/L 15 3 turbidity NTU 0.7 4 chromaticity 13 5 pH 6.9 6 conductivity μS/cm 8 [0000] TABLE 9 Measured No. Item Unit value 1 COD Cr mg/L 83 2 SS mg/L 55 3 turbidity NTU 3 4 chromaticity 30 5 saltness ‰ 2.7 6 pH 8.5 7 conductivity μS/cm 6500 Example 4 [0071] A process for purifying deeply treating printing and dyeing wastewater of 20,000 tons per day and reusing recycled water.", "[0072] The deeply treating printing and dyeing wastewater has measured indexes shown in Table 10.", "[0073] The deeply treating printing and dyeing wastewater is drawn via the first pump 12 for 1000 T/H.", "A first part thereof flows into the nanometer catalytic microelectrolysis tank 13 via a T-cock for 250 T/H, when the system runs stably and the concentrated liquid flows to recycle, a flow speed through the nanometer catalytic microelectrolysis tank 13 is adjusted to be 360 T/H, wherein the deeply treating printing and dyeing wastewater is 250 T/H, the concentrated liquid after reflowing for catalytic microelectrolysis for 110 T/H, flows into the neutralization tank 16 via a first one-way valve 15 , and a second part flows directly into the neutralization tank 16 to mix with the printing and dyeing wastewater purified by nanometer catalytic microelectrolysis for precipitation for 750 T/H via the T-cock, a pipe and a second one-way valve 14 , is filtered by a crude filter tank 17 , and pumped into the adsorption and filteration device of granular active carbon 18 to be adsorbed and filtered, so as to remove solid impurity, plankton, bacteria, and colloids from the printing and dyeing wastewater to obtain purified wastewater.", "[0000] TABLE 10 Measured No. Item Unit value 1 COD Cr mg/L 155 2 SS mg/L 182 3 turbidity NTU 6.5 4 chromaticity 1.5 5 pH 7.7 6 conductivity μS/cm 6900 [0074] Due to low saltness of the deeply treating printing and dyeing wastewater, industrial NaCl is added to increase the saltness up to 9.5 0 / 00 , and then nanometer catalytic microelectrolysis is processed.", "A working voltage of the nanometer catalytic microelectrolysis is 6˜7 V, a current intensity is 4950˜5000 A. The nascent state chlorine produced by nanometer catalytic microelectrolysis oxidates and degrades organic matters in the wastewater, and forms relatively big coagulation of suspended matter, colloid and charged particles in the wastewater under effect of electric field to be removed by crude filtering and fine filtering for purifying the wastewater.", "A measured SDI is 2.6.", "[0075] The purified wastewater, which is purified by nanometer catalytic microelectrolysis, is pumped into the reverse osmosis filtration membrane system 25 via the second stop valve 21 and the high-pressure pump 24 to obtain the dialyzed liquid and the concentrated liquid, flowing speeds of the dialyzed liquid and the concentrated liquid are respectively 400.00 T/H and 860.00 T/H.", "The concentrated liquid reflows to be reused via the fourth stop valve 36 and the fifth stop valve 37 for 150.00 T/H, reflows into the nanometer catalytic microelectrolysis tank 13 via the seventh stop valve 39 to be reused for 110.00 T/H, and drains the rest for 140.00 T/H.", "The recycled rate of the wastewater is 86%, qualities of the recycled water are shown in Table 11, and indexes of the concentrated liquid are shown in Table 12.", "[0000] TABLE 11 Measured No. Item Unit value 1 COD Cr mg/L 9 2 SS mg/L 20 3 turbidity NTU 0.9 4 chromaticity 13 5 pH 7.4 6 Hardness mmol/l [0000] TABLE 12 Measured No. Item Unit value 1 COD Cr mg/L 95 2 SS mg/L 39 3 turbidity NTU 1.9 4 saltness ‰ 11.5 5 pH 8.2 6 conductivity μS/cm 9200 [0076] A nanofiltration membrane of the nanofiltration membrane filtration and separation system, is a nanofiltration rolling membrane having MgSO 4 retention rate of 98%, a working condition is 20∞45° C. , a working pressure is 6.5˜15.0 bar, and a membrane flux is 29 ml/cm 2 ." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 12/835,483, filed on Jul. 13, 2010, which is a continuation of International application No. PCT/CN2009/070163, filed on Jan. 15, 2009. The International Application claims priority to Chinese Patent Application No. 200810006272.7, filed on Feb. 4, 2008. The afore-mentioned patent applications are hereby incorporated by reference in their entireties. TECHNICAL FIELD The present disclosure relates to the field of mobile communication technology, and particularly to a method and a system for processing a bearer under an idle mode signaling reduction (ISR) mechanism. BACKGROUND A core network of a wireless evolution network mainly includes three logic function entities, namely, a mobility management entity (MME), a serving gateway (SGW), and a packet data network gateway (PGW). The MME, as a mobility management network element, is responsible for functions such as signaling encryption, roaming, tracking, assignment of temporary subscriber identities and security functions, and the MME corresponds to a control plane part a General Packet Radio Service (GPRS) support node inside a current system. The SGW is responsible for local mobile anchor points and mobile anchor points inside a system and lawful interception of relevant information. The PGW is responsible for policy execution and charging and lawful interception of relevant functions. The policy execution and charging is on the basis of a policy and charging control (PCC) rule, which is delivered to the PGW by a policy and charging rules function (PCRF) entity. As the PCRF entity delivers the PCC rule, the PCC rule needs to be determined according to a current radio access type (RAT) of a user. Different RATs may deliver different PCC rules. Signaling reduction, also called idle mode signaling reduction, can function to reduce signaling over air interface only if the user equipment (UE) is in an idle mode. If an ISR mechanism is adopted for 2G and/or 3G, the user plane in the idle mode is terminated at the SGW. Therefore, under the case that a signaling reduction mechanism is initiated at the user and the network side, the network side cannot know the specific network of the user is 2/3G or a Local Term Evolution (LTE). In the ISR mechanism, when the user in 2/3G is in IDLE mode, and handovers from a source side 2/3G network to a target side LTE network, since the PGW knows nothing of the user state, and still holds the PCC policy corresponding to the access of the source side 2/3G network, and at this time, the IDLE mode user may possibly be in the LTE access network. If the PGW initiates bearer establishing/modifying/deleting procedure, after the MME pages the user, the bearer establishing/modifying/deleting process will be executed at the side of the LTE, thereby successfully establishing/modifying/deleting the bearer. However, the PCC policy on which the establishing/modifying/deleting process of the bearer initiated by the PGW is based is directed to the access mode of 2/3G. In the conventional art, under the ISR mechanism, when the network side initiates the bearer establishing/modifying/deleting process for the IDLE user, the access mode to which the PCC policy directed may possibly be inconsistent with the access mode of the resident network of the user. SUMMARY The exemplary embodiments described below provide a method and a system for processing a bearer under an ISR mechanism, which can ensure that an access mode in a bearing procedure under the ISR mechanism is consistent with an access mode of a current network of a user. An embodiment provides a method for processing a bearer under an ISR mechanism, which includes the following steps. An access mode of a current network is acquired. The access mode of the current network is notified to an SGW, so that the SGW performs bearer processing according to the access mode of the current network. Another embodiment provides a mobile network system, which includes a mobility management network element and an SGW. The mobility management network element is configured to acquire an access mode of a current network. The SGW is configured to acquire the access mode of the current network from the mobility management network element, and perform a bearing procedure according to the access mode of the current network. Yet another embodiment provides a mobility management network element, which includes an acquisition unit and a notification unit. The acquisition unit is configured to acquire the access mode of the current network. The notification unit is configured to notify the SGW of the access mode of the current network acquired by the acquisition unit. Still another embodiment provides an SGW, which includes a receiving unit and a bearer processing unit. The receiving unit is configured to receive the access mode of the current network sent by the mobility management network element. The bearer processing unit is configured to perform bearer processing according to the access mode of the current network received by the receiving unit. Regarding the method and system for processing a bearer under an ISR mechanism provided in the embodiments, the mobility management network element firstly acquires the access mode of the current network and notifies the SGW of the acquired access mode, and the SGW then performs the bearing procedure according to the acquired access mode of the current network. Therefore, the problem that the access mode to which the PCC policy adopted by the network side directed during a bearing procedure is inconsistent with the access mode of the current network can be avoided, which is caused because the network cannot know the access technique of the current network. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B are a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a first embodiment; FIGS. 2A and 2B are a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a second embodiment; FIGS. 3A and 3B are a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a third embodiment; FIG. 4 is a schematic structural view of a mobile network system according to an embodiment; FIG. 5 is a schematic structural view of a mobility management network element according to an embodiment; and FIG. 6 is a schematic structural view of an SGW according to an embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS The exemplary embodiments described below provide a method and a system for processing a bearer under an ISR mechanism. In order to make the technical solutions clearer and more comprehensible, embodiments with reference to the accompanying drawings are described. Referring to FIGS. 1A AND 1B , a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a first embodiment is shown. The bearer processing procedure may be a bearer activation or processing procedure. In this embodiment, the bearer activation procedure under an ISR mechanism is described. User equipment (UE) in an IDLE state is moved from an original resident network to a current network. The process of initiating a bearer activation procedure under the ISR mechanism specifically includes the following steps. In step 101 , a PCRF delivers a PCC rule to a PGW. The PCC rule is a PCC rule corresponding to an access mode of the original resident network. If the PCC rule is not configured by the PCRF, a Quality of Service (QoS) rule may also be configured by the PGW. In step 102 , the PGW, according to the PCC rule, sends a create bearer request to an SGW. The aforementioned is the bearer activation process triggered by the PGW. The PCRF may also directly deliver the PCC rule to the SGW to trigger the bearer activation process, or the SGW configures the QoS rule. In step 103 , after confirming that the UEs at access modes of a source side and a target side are in an IDLE state, the SGW stores the create bearer request, and notifies a mobility management network element in the current network and a mobility management network element at another network side to initiate a UE paging procedure. The mobility management network element above may be a Mobility Management Entity (MME) or a Service GPRS Support Node (SGSN). In this embodiment, the SGW may notify the mobility management network element in the current network and the mobility management network element in the original resident network to initiate paging through a downlink data notification message or another new message. In step 104 , after receiving a service request from the UE, the mobility management network element in the current network acquires the access mode of the current network, and notifies the SGW of the access mode of the current network. The mobility management network element in the current network may also acquire the access mode of the current network by other means. For example, the mobility management network element in the current network sends a message of acquiring the access mode of the current network to the current network, and the current network returns a response message carrying the access mode of the current network. In Step 105 , the SGW compares the acquired access mode of the current network with the recorded access mode of the original resident network to determine whether they are the same. If yes, the process proceeds to step 106 ; otherwise, the process proceeds to step 107 . The SGW stores the access mode of the original resident network therein. In step 106 , the SGW extracts the stored create bearer request and continue the bearer activation process. For example, the current network and the original resident network are both 2G/3G networks. Since the bearer activation process is substantially the same as the bearer activation process in the prior art, it will not be described in detail here. In step 107 , the SGW returns a response message for rejecting bearer activation to the PGW. The response message for rejecting bearer activation may carry the access mode of the current network. Specifically, the SGW may carry the access mode of the current network as a parameter in the response message for rejecting bearer activation and send it to the PGW. The response message for rejecting bearer activation may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause. In step 108 , the SGW sends an update bearer request to the PGW, which carries the access mode of the current network. For example, the current network is a 2G/3G network, and the original resident network is an LTE network. Thus, the update bearer request message sent by the SGW to the PGW carries the access mode of the current 2G/3G network. Specifically, the SGW may carry the access mode of the current network as a parameter in the update bearer request message and send it to the PGW. The update bearer request message may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause. When the SGW is connected to multiple packet data networks (PDNs), it sends the update bearer request message to multiple PGWs. In step 109 , the PGW returns an update bearer response message to the SGW. In step 110 , the PGW sends the access mode of the current network to the PCRF, and acquires the PCC rule corresponding to the access mode of the current network from the PCRF. In step 111 , the PGW initiates a bearer activation process according to the acquired PCC rule corresponding to the access mode of the current network. If, in steps 101 - 102 , the PCRF directly delivers the PCC rule to the SGW to trigger the bearer activation process, the process from step 107 to step 111 is as follows. The SGW sends the access mode of the current network to the PCRF, and the PCRF sends the PCC rule corresponding to the access mode of the current network to the SGW and the PGW. The SGW initiates the bearer activation process according to the PCC rule corresponding to the access mode of the current network. The present disclosure is applicable to not only the bearer activation procedure in the embodiment, but also bearer modifying and deleting procedures, which are substantially similar to the bearer activation procedure and will not be further described here. Referring to FIGS. 2A AND 2B , a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a second embodiment is shown. The bearer processing procedure may be a bearer initiating or processing procedure. This embodiment is still described according to the bearer activation procedure under the ISR mechanism. UE in an IDLE state is moved from an original resident network to a current network. The specific signaling flow of initiating a bearer activation procedure under the ISR mechanism includes the following steps. In step 201 , a PCRF delivers a PCC rule to a PGW. The PCC rule is a PCC rule corresponding to an access mode of the original resident network. If the PCC rule is not configured by the PCRF, a QoS rule may also be configured by the PGW. In step 202 , the PGW, according to the PCC rule, sends a create bearer request to an SGW. The PCRF may also directly deliver the PCC rule to the SGW to trigger the bearer activation process, or the SGW configures the QoS rule. In step 203 , if the SGW finds that the user is in an IDLE state in two access modes under the ISR mechanism, it sends a create bearer request to a mobility management network element in the current network and a mobility management network element in the original resident network. In step 204 , the mobility management network element in the current network and the mobility management network element in the original resident network firstly store signaling and then page the user, and the mobility management network element in the current network acquires the access mode of the UE after receiving the service request of the UE. The mobility management network element of the current network may also acquire the access mode of the current network by other means, for example, sending a message of acquiring the access mode of the current network to the current network, and the current network returns a response message carrying the access mode of the current network. In step 205 , the mobility management network element of the current network continues performing the bearer activation process, and sends an update bearer request message to the SGW. The update bearer request message carries the access mode of the current network, and the SGW returns an update bearer response message to the mobility management network element of the current network. In step 206 , the SGW notifies the mobility management network element of the original resident network to stop paging the user, and stop processing the previously received create bearer request. The SGW compares the access mode of the current network with the access mode of the original resident network to determine whether they are the same. If they are not the same, the process proceeds to step 207 . The SGW stores the access mode of the original resident network therein. In step 207 , the SGW sends the update bearer request message to the PGW. The update bearer request message may carry the access mode of the current network. Specifically, the SGW may carry the access mode of the current network as a parameter in the update bearer request message and send it to the PGW. The update bearer request message may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause. When the SGW is connected to multiple PDNs, it sends the update bearer request message to multiple PGWs. In step 208 , the PGW returns an update bearer response message to the SGW. In step 209 , the PGW sends the access mode of the current network to the PCRF, and acquires the PCC rule corresponding to the access mode of the current network from the PCRF. In step 210 , after the bearer activation process is ended, the PGW initiates a bearer modifying process according to the acquired PCC rule corresponding to the access mode of the current network. If, in steps 201 - 202 , the PCRF directly delivers the PCC rule to the SGW to trigger the bearer activation process, the process from step 207 to step 210 is as follows. The SGW sends the access mode of the current network to the PCRF, and the PCRF sends the PCC rule corresponding to the access mode of the current network to the SGW and the PGW. After the bearer activation process is ended, the SGW initiates the bearer modifying process according to the PCC rule corresponding to the access mode of the current network. The present disclosure is applicable to not only the bearer activation procedure in the embodiment, but also bearer modifying and deleting procedures, which are substantially similar to the bearer activation procedure and will not be further described here. Referring to FIGS. 3A AND 3B , a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a third embodiment is shown. The bearer processing procedure may be a bearer initiating or processing procedure. This embodiment is still described according to the bearer activation procedure under the ISR mechanism. UE in an IDLE state is moved from an original resident network to a current network. In step 301 , a PCRF delivers a PCC rule to a PGW. The PCC rule is a PCC rule corresponding to an access mode of the original resident network. If the PCC rule is not configured by the PCRF, a QoS rule may also be configured by the PGW. In step 302 , the PGW sends, according to the acquired PCC rule, a create bearer request to an SGW. Of course, the PCRF may also directly deliver the PCC rule to the SGW to trigger the bearer activation process, or the SGW configures the QoS rule. In step 303 , if the user is in an IDLE state in two access modes under the ISR mechanism, the SGW sends a create bearer request message to a mobility management network element in the current network and a mobility management network element in the original resident network. The message carries the access mode of the original resident network recorded in the SGW. In step 304 , the mobility management network element in the current network and the mobility management network element in the original resident network firstly store signaling and then page the user, and the access mode of the current network is acquired by paging the user. The mobility management network element of the current network may also acquire the access mode of the current network by other means, for example, the mobility management network element of the current network sends a message of acquiring the access mode of the current network to the current network, and the current network returns a response message carrying the information of the access mode of the current network. In step 305 , the mobility management network element of the current network compares the acquired access mode of the current network with the access mode of the original resident network carried in the message of the bearer request sent by the SGW to determine whether they are the same. If yes, the process proceeds to step 306 ; otherwise, the process proceeds to step 307 . In step 306 , the mobility management network element extracts the stored create bearer request and continues the bearer activation process. Since the bearer activation process is substantially the same as the bearer activation process in the prior art, it will not be described in detail here. In step 307 , the mobility management network element of the current network returns the create bearer response message to the SGW, which carries the access mode of the current network. The mobility management network element of the current network may also send the access mode of the current network to the SGW by the update bearer request message. In step 308 , the SGW returns a response message for rejecting bearer activation to the PGW. The response message for rejecting bearer activation may carry the access mode of the current network. Specifically, the SGW may carry the access mode of the current network as a parameter in the response message for rejecting bearer activation and send it to the PGW. The response message for rejecting bearer activation may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause. In step 309 , the SGW sends an update bearer request message to the PGW, which carries the access mode of the current network. Specifically, the SGW may carry the access mode of the current network as a parameter in the update bearer request message and send it to the PGW. The update bearer request message may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause. When the SGW is connected to multiple PDNs, it sends the update bearer request message to multiple PGWs. In step 310 , the PGW returns an update bearer response message to the SGW. In step 311 , the PGW sends the access mode of the current network to the PCRF, and acquires the PCC rule corresponding to the access mode of the current network from PCRF. In step 312 , the PGW initiates a bearer activation process according to the acquired PCC rule corresponding to the access mode of the current network. If, in steps 301 - 302 , the PCRF directly delivers the PCC rule to the SGW to trigger the bearer activation process, the process from step 308 to step 312 is as follows. The SGW sends the access mode of the current network to the PCRF, and the PCRF sends the PCC rule corresponding to the access mode of the current network to the SGW and the PGW. The SGW initiates the bearer activation process according to the acquired PCC rule corresponding to the access mode of the current network. The present disclosure is applicable to not only the bearer activation procedure in the embodiment, but also bearer modifying and deleting procedures, which are substantially similar to the bearer activation procedure and will not be further described here. Referring to FIG. 4 , a schematic structural view of an embodiment of a mobile network system is shown. The mobile network system includes a mobility management network element 41 , an SGW 42 , a PGW 43 , a PCRF entity 44 . The mobility management network element 41 is configured to acquire an access mode of a current network, which may be an MME or an SGSN. The SGW 42 is configured to acquire the access mode of the current network from the mobility management network element 41 , and perform a bearing process according to the access mode of the current network. The PCRF entity 44 is configured to receive the access mode of the current network sent by the SGW 42 and provide a PCC rule corresponding to the access mode of the current network for the SGW 42 or the PGW 43 . The PGW 43 is configured to send the access mode of the current network acquired by the SGW 42 to the PCRF entity 44 , and initiate a bearing process according to the PCC rule corresponding to the access mode of the current network provided by the PCRF entity 44 . Referring to FIG. 5 , a schematic structural view of an embodiment of a mobility management network element is shown. The mobility management network element includes an acquisition unit 51 , a notification unit 52 , and a comparison unit 53 . The acquisition unit 51 is configured to acquire the access mode of the current network. The notification unit 52 is configured to notify the SGW of the access mode of the current network acquired by the acquisition unit 51 . The acquisition unit 51 includes a receiving unit 511 and a paging unit 512 . The receiving unit 511 is configured to receive a bearer request initiated by the SGW or receive a notification message of paging a user initiated by the SGW. The paging unit 512 is configured to initiate a user paging according to the bearer request or the notification message of paging a user received by the receiving unit 511 , and acquire the access mode of the current network through the user paging. The comparison unit 53 is configured to compare the access mode of the current network with the access mode of the original resident network. When the comparison result indicates that the access mode of the current network is different from the access mode of the original resident network, the notification unit 52 notifies the SGW of the access mode of the current network. The mobility management network element further includes a storage unit. The storage unit is configured to store the bearer request received by the receiving unit. Referring to FIG. 6 , a schematic structural view of an embodiment of an SGW is shown. The SGW includes a receiving unit 61 , a bearer processing unit 62 , a recording unit 63 , and a comparison unit 64 . The receiving unit 61 is configured to receive the access mode of the current network sent by the mobility management network element. The bearer processing unit 62 is configured to perform bearer processing according to the access mode of the current network received by the receiving unit 61 . The recording unit 63 is configured to record the access mode of the original resident network. The comparison unit 64 is configured to compare the access mode of the current network received by the receiving unit 61 with the access mode of the original resident network recorded by the recording unit 63 . When the comparison result indicates that the access mode of the current network is different from the access mode of the original resident network, the bearer processing unit 62 performs bearer processing according to the access mode of the current network received by the receiving unit 61 . The SGW can further include a bearer request receiving unit and a sending unit. The bearer request receiving unit is configured to receive the bearer quest sent by the PGW. The sending unit is configured to notify the mobility management network element to page a user. The SGW may further include a notification unit. The notification unit is configured to notify the PGW of the access mode of the current network received by the receiving unit. Through the method for processing a bearer under an ISR mechanism, the mobile network system, the mobility management network element, the SGW provided in the embodiments, the mobility management network element firstly acquires the access mode of the current network and notifies the SGW of the acquired access mode, and the SGW then performs the bearing procedure according to the acquired access mode of the current network. Therefore, the problem that the access mode to which the PCC policy adopted by the network side directed during a bearing procedure is inconsistent with the access mode of the current network can be avoided, which is caused because the network cannot know the access technique of the current network. The method for processing a bearer under an ISR mechanism is introduced above in detail. It is understood that persons of ordinary skill may make variations to the described embodiments with departing from the scope of the claims. Moreover, it is understood that the scope of the claims is not limited to any particular embodiment, described above.
A method and a system for processing a bearer under an idle mode signaling reduction (ISR) mechanism are provided. The method for processing a bearer under an ISR mechanism includes the following steps. A mobility management network element acquires an access mode of a current network. The mobility management network element notifies a serving gateway (SGW) of the access mode of the current network, so that the SGW processes bearer according to the access mode of the current network. It can be ensured that the access mode of the current network is consistent with the access mode for a policy and charging control (PCC) strategy adopted during a bearing procedure under the ISR mechanism.
Summarize the patent document, focusing on the invention's functionality and advantages.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser.", "No. 12/835,483, filed on Jul. 13, 2010, which is a continuation of International application No. PCT/CN2009/070163, filed on Jan. 15, 2009.", "The International Application claims priority to Chinese Patent Application No. 200810006272.7, filed on Feb. 4, 2008.", "The afore-mentioned patent applications are hereby incorporated by reference in their entireties.", "TECHNICAL FIELD The present disclosure relates to the field of mobile communication technology, and particularly to a method and a system for processing a bearer under an idle mode signaling reduction (ISR) mechanism.", "BACKGROUND A core network of a wireless evolution network mainly includes three logic function entities, namely, a mobility management entity (MME), a serving gateway (SGW), and a packet data network gateway (PGW).", "The MME, as a mobility management network element, is responsible for functions such as signaling encryption, roaming, tracking, assignment of temporary subscriber identities and security functions, and the MME corresponds to a control plane part a General Packet Radio Service (GPRS) support node inside a current system.", "The SGW is responsible for local mobile anchor points and mobile anchor points inside a system and lawful interception of relevant information.", "The PGW is responsible for policy execution and charging and lawful interception of relevant functions.", "The policy execution and charging is on the basis of a policy and charging control (PCC) rule, which is delivered to the PGW by a policy and charging rules function (PCRF) entity.", "As the PCRF entity delivers the PCC rule, the PCC rule needs to be determined according to a current radio access type (RAT) of a user.", "Different RATs may deliver different PCC rules.", "Signaling reduction, also called idle mode signaling reduction, can function to reduce signaling over air interface only if the user equipment (UE) is in an idle mode.", "If an ISR mechanism is adopted for 2G and/or 3G, the user plane in the idle mode is terminated at the SGW.", "Therefore, under the case that a signaling reduction mechanism is initiated at the user and the network side, the network side cannot know the specific network of the user is 2/3G or a Local Term Evolution (LTE).", "In the ISR mechanism, when the user in 2/3G is in IDLE mode, and handovers from a source side 2/3G network to a target side LTE network, since the PGW knows nothing of the user state, and still holds the PCC policy corresponding to the access of the source side 2/3G network, and at this time, the IDLE mode user may possibly be in the LTE access network.", "If the PGW initiates bearer establishing/modifying/deleting procedure, after the MME pages the user, the bearer establishing/modifying/deleting process will be executed at the side of the LTE, thereby successfully establishing/modifying/deleting the bearer.", "However, the PCC policy on which the establishing/modifying/deleting process of the bearer initiated by the PGW is based is directed to the access mode of 2/3G.", "In the conventional art, under the ISR mechanism, when the network side initiates the bearer establishing/modifying/deleting process for the IDLE user, the access mode to which the PCC policy directed may possibly be inconsistent with the access mode of the resident network of the user.", "SUMMARY The exemplary embodiments described below provide a method and a system for processing a bearer under an ISR mechanism, which can ensure that an access mode in a bearing procedure under the ISR mechanism is consistent with an access mode of a current network of a user.", "An embodiment provides a method for processing a bearer under an ISR mechanism, which includes the following steps.", "An access mode of a current network is acquired.", "The access mode of the current network is notified to an SGW, so that the SGW performs bearer processing according to the access mode of the current network.", "Another embodiment provides a mobile network system, which includes a mobility management network element and an SGW.", "The mobility management network element is configured to acquire an access mode of a current network.", "The SGW is configured to acquire the access mode of the current network from the mobility management network element, and perform a bearing procedure according to the access mode of the current network.", "Yet another embodiment provides a mobility management network element, which includes an acquisition unit and a notification unit.", "The acquisition unit is configured to acquire the access mode of the current network.", "The notification unit is configured to notify the SGW of the access mode of the current network acquired by the acquisition unit.", "Still another embodiment provides an SGW, which includes a receiving unit and a bearer processing unit.", "The receiving unit is configured to receive the access mode of the current network sent by the mobility management network element.", "The bearer processing unit is configured to perform bearer processing according to the access mode of the current network received by the receiving unit.", "Regarding the method and system for processing a bearer under an ISR mechanism provided in the embodiments, the mobility management network element firstly acquires the access mode of the current network and notifies the SGW of the acquired access mode, and the SGW then performs the bearing procedure according to the acquired access mode of the current network.", "Therefore, the problem that the access mode to which the PCC policy adopted by the network side directed during a bearing procedure is inconsistent with the access mode of the current network can be avoided, which is caused because the network cannot know the access technique of the current network.", "BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B are a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a first embodiment;", "FIGS. 2A and 2B are a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a second embodiment;", "FIGS. 3A and 3B are a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a third embodiment;", "FIG. 4 is a schematic structural view of a mobile network system according to an embodiment;", "FIG. 5 is a schematic structural view of a mobility management network element according to an embodiment;", "and FIG. 6 is a schematic structural view of an SGW according to an embodiment.", "DETAILED DESCRIPTION OF THE EMBODIMENTS The exemplary embodiments described below provide a method and a system for processing a bearer under an ISR mechanism.", "In order to make the technical solutions clearer and more comprehensible, embodiments with reference to the accompanying drawings are described.", "Referring to FIGS. 1A AND 1B , a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a first embodiment is shown.", "The bearer processing procedure may be a bearer activation or processing procedure.", "In this embodiment, the bearer activation procedure under an ISR mechanism is described.", "User equipment (UE) in an IDLE state is moved from an original resident network to a current network.", "The process of initiating a bearer activation procedure under the ISR mechanism specifically includes the following steps.", "In step 101 , a PCRF delivers a PCC rule to a PGW.", "The PCC rule is a PCC rule corresponding to an access mode of the original resident network.", "If the PCC rule is not configured by the PCRF, a Quality of Service (QoS) rule may also be configured by the PGW.", "In step 102 , the PGW, according to the PCC rule, sends a create bearer request to an SGW.", "The aforementioned is the bearer activation process triggered by the PGW.", "The PCRF may also directly deliver the PCC rule to the SGW to trigger the bearer activation process, or the SGW configures the QoS rule.", "In step 103 , after confirming that the UEs at access modes of a source side and a target side are in an IDLE state, the SGW stores the create bearer request, and notifies a mobility management network element in the current network and a mobility management network element at another network side to initiate a UE paging procedure.", "The mobility management network element above may be a Mobility Management Entity (MME) or a Service GPRS Support Node (SGSN).", "In this embodiment, the SGW may notify the mobility management network element in the current network and the mobility management network element in the original resident network to initiate paging through a downlink data notification message or another new message.", "In step 104 , after receiving a service request from the UE, the mobility management network element in the current network acquires the access mode of the current network, and notifies the SGW of the access mode of the current network.", "The mobility management network element in the current network may also acquire the access mode of the current network by other means.", "For example, the mobility management network element in the current network sends a message of acquiring the access mode of the current network to the current network, and the current network returns a response message carrying the access mode of the current network.", "In Step 105 , the SGW compares the acquired access mode of the current network with the recorded access mode of the original resident network to determine whether they are the same.", "If yes, the process proceeds to step 106 ;", "otherwise, the process proceeds to step 107 .", "The SGW stores the access mode of the original resident network therein.", "In step 106 , the SGW extracts the stored create bearer request and continue the bearer activation process.", "For example, the current network and the original resident network are both 2G/3G networks.", "Since the bearer activation process is substantially the same as the bearer activation process in the prior art, it will not be described in detail here.", "In step 107 , the SGW returns a response message for rejecting bearer activation to the PGW.", "The response message for rejecting bearer activation may carry the access mode of the current network.", "Specifically, the SGW may carry the access mode of the current network as a parameter in the response message for rejecting bearer activation and send it to the PGW.", "The response message for rejecting bearer activation may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause.", "In step 108 , the SGW sends an update bearer request to the PGW, which carries the access mode of the current network.", "For example, the current network is a 2G/3G network, and the original resident network is an LTE network.", "Thus, the update bearer request message sent by the SGW to the PGW carries the access mode of the current 2G/3G network.", "Specifically, the SGW may carry the access mode of the current network as a parameter in the update bearer request message and send it to the PGW.", "The update bearer request message may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause.", "When the SGW is connected to multiple packet data networks (PDNs), it sends the update bearer request message to multiple PGWs.", "In step 109 , the PGW returns an update bearer response message to the SGW.", "In step 110 , the PGW sends the access mode of the current network to the PCRF, and acquires the PCC rule corresponding to the access mode of the current network from the PCRF.", "In step 111 , the PGW initiates a bearer activation process according to the acquired PCC rule corresponding to the access mode of the current network.", "If, in steps 101 - 102 , the PCRF directly delivers the PCC rule to the SGW to trigger the bearer activation process, the process from step 107 to step 111 is as follows.", "The SGW sends the access mode of the current network to the PCRF, and the PCRF sends the PCC rule corresponding to the access mode of the current network to the SGW and the PGW.", "The SGW initiates the bearer activation process according to the PCC rule corresponding to the access mode of the current network.", "The present disclosure is applicable to not only the bearer activation procedure in the embodiment, but also bearer modifying and deleting procedures, which are substantially similar to the bearer activation procedure and will not be further described here.", "Referring to FIGS. 2A AND 2B , a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a second embodiment is shown.", "The bearer processing procedure may be a bearer initiating or processing procedure.", "This embodiment is still described according to the bearer activation procedure under the ISR mechanism.", "UE in an IDLE state is moved from an original resident network to a current network.", "The specific signaling flow of initiating a bearer activation procedure under the ISR mechanism includes the following steps.", "In step 201 , a PCRF delivers a PCC rule to a PGW.", "The PCC rule is a PCC rule corresponding to an access mode of the original resident network.", "If the PCC rule is not configured by the PCRF, a QoS rule may also be configured by the PGW.", "In step 202 , the PGW, according to the PCC rule, sends a create bearer request to an SGW.", "The PCRF may also directly deliver the PCC rule to the SGW to trigger the bearer activation process, or the SGW configures the QoS rule.", "In step 203 , if the SGW finds that the user is in an IDLE state in two access modes under the ISR mechanism, it sends a create bearer request to a mobility management network element in the current network and a mobility management network element in the original resident network.", "In step 204 , the mobility management network element in the current network and the mobility management network element in the original resident network firstly store signaling and then page the user, and the mobility management network element in the current network acquires the access mode of the UE after receiving the service request of the UE.", "The mobility management network element of the current network may also acquire the access mode of the current network by other means, for example, sending a message of acquiring the access mode of the current network to the current network, and the current network returns a response message carrying the access mode of the current network.", "In step 205 , the mobility management network element of the current network continues performing the bearer activation process, and sends an update bearer request message to the SGW.", "The update bearer request message carries the access mode of the current network, and the SGW returns an update bearer response message to the mobility management network element of the current network.", "In step 206 , the SGW notifies the mobility management network element of the original resident network to stop paging the user, and stop processing the previously received create bearer request.", "The SGW compares the access mode of the current network with the access mode of the original resident network to determine whether they are the same.", "If they are not the same, the process proceeds to step 207 .", "The SGW stores the access mode of the original resident network therein.", "In step 207 , the SGW sends the update bearer request message to the PGW.", "The update bearer request message may carry the access mode of the current network.", "Specifically, the SGW may carry the access mode of the current network as a parameter in the update bearer request message and send it to the PGW.", "The update bearer request message may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause.", "When the SGW is connected to multiple PDNs, it sends the update bearer request message to multiple PGWs.", "In step 208 , the PGW returns an update bearer response message to the SGW.", "In step 209 , the PGW sends the access mode of the current network to the PCRF, and acquires the PCC rule corresponding to the access mode of the current network from the PCRF.", "In step 210 , after the bearer activation process is ended, the PGW initiates a bearer modifying process according to the acquired PCC rule corresponding to the access mode of the current network.", "If, in steps 201 - 202 , the PCRF directly delivers the PCC rule to the SGW to trigger the bearer activation process, the process from step 207 to step 210 is as follows.", "The SGW sends the access mode of the current network to the PCRF, and the PCRF sends the PCC rule corresponding to the access mode of the current network to the SGW and the PGW.", "After the bearer activation process is ended, the SGW initiates the bearer modifying process according to the PCC rule corresponding to the access mode of the current network.", "The present disclosure is applicable to not only the bearer activation procedure in the embodiment, but also bearer modifying and deleting procedures, which are substantially similar to the bearer activation procedure and will not be further described here.", "Referring to FIGS. 3A AND 3B , a signaling flow chart of a method for processing a bearer under an ISR mechanism according to a third embodiment is shown.", "The bearer processing procedure may be a bearer initiating or processing procedure.", "This embodiment is still described according to the bearer activation procedure under the ISR mechanism.", "UE in an IDLE state is moved from an original resident network to a current network.", "In step 301 , a PCRF delivers a PCC rule to a PGW.", "The PCC rule is a PCC rule corresponding to an access mode of the original resident network.", "If the PCC rule is not configured by the PCRF, a QoS rule may also be configured by the PGW.", "In step 302 , the PGW sends, according to the acquired PCC rule, a create bearer request to an SGW.", "Of course, the PCRF may also directly deliver the PCC rule to the SGW to trigger the bearer activation process, or the SGW configures the QoS rule.", "In step 303 , if the user is in an IDLE state in two access modes under the ISR mechanism, the SGW sends a create bearer request message to a mobility management network element in the current network and a mobility management network element in the original resident network.", "The message carries the access mode of the original resident network recorded in the SGW.", "In step 304 , the mobility management network element in the current network and the mobility management network element in the original resident network firstly store signaling and then page the user, and the access mode of the current network is acquired by paging the user.", "The mobility management network element of the current network may also acquire the access mode of the current network by other means, for example, the mobility management network element of the current network sends a message of acquiring the access mode of the current network to the current network, and the current network returns a response message carrying the information of the access mode of the current network.", "In step 305 , the mobility management network element of the current network compares the acquired access mode of the current network with the access mode of the original resident network carried in the message of the bearer request sent by the SGW to determine whether they are the same.", "If yes, the process proceeds to step 306 ;", "otherwise, the process proceeds to step 307 .", "In step 306 , the mobility management network element extracts the stored create bearer request and continues the bearer activation process.", "Since the bearer activation process is substantially the same as the bearer activation process in the prior art, it will not be described in detail here.", "In step 307 , the mobility management network element of the current network returns the create bearer response message to the SGW, which carries the access mode of the current network.", "The mobility management network element of the current network may also send the access mode of the current network to the SGW by the update bearer request message.", "In step 308 , the SGW returns a response message for rejecting bearer activation to the PGW.", "The response message for rejecting bearer activation may carry the access mode of the current network.", "Specifically, the SGW may carry the access mode of the current network as a parameter in the response message for rejecting bearer activation and send it to the PGW.", "The response message for rejecting bearer activation may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause.", "In step 309 , the SGW sends an update bearer request message to the PGW, which carries the access mode of the current network.", "Specifically, the SGW may carry the access mode of the current network as a parameter in the update bearer request message and send it to the PGW.", "The update bearer request message may further carry a content indicating that the access mode of the current network is inconsistent with the access mode of the original resident network recorded in the PGW, for example, indicating that the access mode stored in the PGW is inconsistent with the current access mode in the value of cause.", "When the SGW is connected to multiple PDNs, it sends the update bearer request message to multiple PGWs.", "In step 310 , the PGW returns an update bearer response message to the SGW.", "In step 311 , the PGW sends the access mode of the current network to the PCRF, and acquires the PCC rule corresponding to the access mode of the current network from PCRF.", "In step 312 , the PGW initiates a bearer activation process according to the acquired PCC rule corresponding to the access mode of the current network.", "If, in steps 301 - 302 , the PCRF directly delivers the PCC rule to the SGW to trigger the bearer activation process, the process from step 308 to step 312 is as follows.", "The SGW sends the access mode of the current network to the PCRF, and the PCRF sends the PCC rule corresponding to the access mode of the current network to the SGW and the PGW.", "The SGW initiates the bearer activation process according to the acquired PCC rule corresponding to the access mode of the current network.", "The present disclosure is applicable to not only the bearer activation procedure in the embodiment, but also bearer modifying and deleting procedures, which are substantially similar to the bearer activation procedure and will not be further described here.", "Referring to FIG. 4 , a schematic structural view of an embodiment of a mobile network system is shown.", "The mobile network system includes a mobility management network element 41 , an SGW 42 , a PGW 43 , a PCRF entity 44 .", "The mobility management network element 41 is configured to acquire an access mode of a current network, which may be an MME or an SGSN.", "The SGW 42 is configured to acquire the access mode of the current network from the mobility management network element 41 , and perform a bearing process according to the access mode of the current network.", "The PCRF entity 44 is configured to receive the access mode of the current network sent by the SGW 42 and provide a PCC rule corresponding to the access mode of the current network for the SGW 42 or the PGW 43 .", "The PGW 43 is configured to send the access mode of the current network acquired by the SGW 42 to the PCRF entity 44 , and initiate a bearing process according to the PCC rule corresponding to the access mode of the current network provided by the PCRF entity 44 .", "Referring to FIG. 5 , a schematic structural view of an embodiment of a mobility management network element is shown.", "The mobility management network element includes an acquisition unit 51 , a notification unit 52 , and a comparison unit 53 .", "The acquisition unit 51 is configured to acquire the access mode of the current network.", "The notification unit 52 is configured to notify the SGW of the access mode of the current network acquired by the acquisition unit 51 .", "The acquisition unit 51 includes a receiving unit 511 and a paging unit 512 .", "The receiving unit 511 is configured to receive a bearer request initiated by the SGW or receive a notification message of paging a user initiated by the SGW.", "The paging unit 512 is configured to initiate a user paging according to the bearer request or the notification message of paging a user received by the receiving unit 511 , and acquire the access mode of the current network through the user paging.", "The comparison unit 53 is configured to compare the access mode of the current network with the access mode of the original resident network.", "When the comparison result indicates that the access mode of the current network is different from the access mode of the original resident network, the notification unit 52 notifies the SGW of the access mode of the current network.", "The mobility management network element further includes a storage unit.", "The storage unit is configured to store the bearer request received by the receiving unit.", "Referring to FIG. 6 , a schematic structural view of an embodiment of an SGW is shown.", "The SGW includes a receiving unit 61 , a bearer processing unit 62 , a recording unit 63 , and a comparison unit 64 .", "The receiving unit 61 is configured to receive the access mode of the current network sent by the mobility management network element.", "The bearer processing unit 62 is configured to perform bearer processing according to the access mode of the current network received by the receiving unit 61 .", "The recording unit 63 is configured to record the access mode of the original resident network.", "The comparison unit 64 is configured to compare the access mode of the current network received by the receiving unit 61 with the access mode of the original resident network recorded by the recording unit 63 .", "When the comparison result indicates that the access mode of the current network is different from the access mode of the original resident network, the bearer processing unit 62 performs bearer processing according to the access mode of the current network received by the receiving unit 61 .", "The SGW can further include a bearer request receiving unit and a sending unit.", "The bearer request receiving unit is configured to receive the bearer quest sent by the PGW.", "The sending unit is configured to notify the mobility management network element to page a user.", "The SGW may further include a notification unit.", "The notification unit is configured to notify the PGW of the access mode of the current network received by the receiving unit.", "Through the method for processing a bearer under an ISR mechanism, the mobile network system, the mobility management network element, the SGW provided in the embodiments, the mobility management network element firstly acquires the access mode of the current network and notifies the SGW of the acquired access mode, and the SGW then performs the bearing procedure according to the acquired access mode of the current network.", "Therefore, the problem that the access mode to which the PCC policy adopted by the network side directed during a bearing procedure is inconsistent with the access mode of the current network can be avoided, which is caused because the network cannot know the access technique of the current network.", "The method for processing a bearer under an ISR mechanism is introduced above in detail.", "It is understood that persons of ordinary skill may make variations to the described embodiments with departing from the scope of the claims.", "Moreover, it is understood that the scope of the claims is not limited to any particular embodiment, described above." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates, in general, to atomizers and, in particular, to a new and useful dual-fluid atomizer having a unique multiple exit orifice and replaceable wear materials. 2. Description of the Related Art Generally, there are many types of atomizers that have been developed in order to atomize a fluid medium into a mist of fine particle size. Most atomizer designs are classified in one of the following categories: 1) hydraulic or mechanical atomizers wherein atomization is accomplished by discharging a fluid at high pressure through an orifice; 2) dynamic atomizers such as a high speed rotary disk or cup; and 3) dual-fluid atomizers in which fluid atomization is achieved by combining a liquid with a compressed gas such as air or steam. Dual-fluid atomizers are further subdivided into two basic types, depending on the location where the atomizing gas and liquid are mixed, i.e. external to the atomizer or internal to the atomizer. With external mix dual-fluid atomizers, the gas and liquid streams are mixed external to the atomizer housing by impinging one jet against the other. With internal mix dual-fluid atomizers, the atomizing gas and liquid streams are mixed internal to the atomizer and discharged through single or multiple exit orifices. For erosive applications where particle-laden liquids, i.e. slurries, are the atomized fluid, the type of atomizer is limited by practical constraints. These constraints include flow capacity, the required size of droplets in the atomized spray (i.e. particle size distribution), the size of internal flow passages, the physical durability of the atomizer components (i.e. service life), the atomizers sensitivity with respect to the degradation of performance due to dimensional change caused by the corrosive and/or erosive nature of the fluid to be atomized, and commercially acceptable energy requirements to produce the atomized spray. There are many different internal mix dual-fluid atomizers that have been developed. U.S. Pat. Nos. 4,819,878 and 5,129,583 disclose two types of dual-fluid atomizers which are currently used. SUMMARY OF THE INVENTION The present invention is an extended wear life, low pressure drop, right angle, multiple exit orifice dual-fluid atomizer which utilizes replaceable wear materials. The unique arrangement of the present invention includes large size internal flow passages which allow for the passage of grit or other relatively large particles without clogging and at the same time produces fine atomization of the liquid fraction. The present invention also facilitates the use of corrosion/erosion resistant materials which fully line the internal wetted surfaces of the atomizer for extending the useful wear life of the atomizer while simultaneously reducing overall operating and maintenance requirements. The present invention utilizes a gas such as compressed air or steam as the atomizing medium to produce a homogeneous mixture of finely atomized liquid droplets containing a uniform dispersion of solids. Where a liquid is not utilized, the present invention produces a fine distribution of powder particles. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawing and descriptive matter in which preferred embodiments of the invention are illustrated. BRIEF DESCRIPTION OF THE DRAWINGS In the drawing: FIG. 1 is a sectional view of a dual-fluid atomizer according to the present invention; and FIG. 2 is an enlarged view of the atomizer head of FIG. 1. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention, as illustrated in FIG. 1, is a dual-fluid atomizer, generally designated 5, comprising an outer barrel 10 having an inner barrel 12 disposed therein and defining an annular space 11 therebetween. The inner barrel 12 has a port or opening 14 at one end for the entry of a slurry, solution, liquid or dry powder flow 6. The outer barrel 10 has an opening 16 for a gas, air or steam flow 8 which flows through annulus 11. The outer barrel 10 and the inner barrel 12 are connected to a mix chamber housing 18 of an atomizer housing 30. The outer barrel 10 and the inner barrel 12 are connected to the chamber housing 18 at their ends opposite openings 16 and 14, respectively. When the present invention is used in a preferred embodiment for atomizing a slurry, chamber housing 18 has an opening 15 which permits the entry of the slurry flow 6 into a primary mix chamber wear sleeve 22 and a secondary mix chamber wear sleeve 24 of the chamber housing 18. Adaptor coupling 26 secures the atomizer housing 30, the mix chamber housing 18 and outer barrel 10. Inner barrel 12 directs the slurry 6 at low velocities to the inlet of the primary mix chamber wear sleeve 22 where it is initially mixed with atomizing gas 8 provided by outer barrel 10 which enters through gas ports 20 in the primary mix chamber wear sleeve 22. In the primary mix chamber wear sleeve 22, a three-phase homogeneous mixture of gas, liquid and solid particles flow therethrough and into the secondary mix chamber wear sleeve 24 wherein it impacts a wear plug 32 located at one end of the secondary mix chamber wear sleeve 24 within the atomizer housing 30. Sleeves 22 and 24 and wear plug 32 as well as inserts 34 are made of a wear-resistant material such as ceramic material. The homogeneous mixture is then directed to an inlet 28 of a perpendicular orifice insert 34 in the atomizer housing 30. As illustrated in FIG. 2, perpendicular orifice insert 34 has a reservoir 50 at an end opposite the port 28. The three-phase mixture flows through the perpendicular orifice insert 34 and into the reservoir 50 which is a conical-shaped reservoir formed by the perpendicular orifice insert 34 and nozzle assembly 36. At the downstream end of the reservoir 50, a wear pad 52 is located which is also located adjacent orifices 54. The three-phase mixture impacts into the wear pad 52 at the reservoir 50 which results in a further homogenization of the mixture prior to discharge. The homogenized slurry is then discharged through exit orifices 54 in the nozzle assembly 36. The exit orifices 54 located in the assembly 36 communicate with the reservoir 50 for discharging the mixture as an atomized fine mist with a homogeneous distribution of solid particles as it exits through ports 56 located at the end of orifices 54. The exit orifices 54 are holes which are bored through exit orifice inserts 55 which can be made from wear resistant material and preferably touch tangent to each other and are inserted into the nozzle assembly 36 and are maintained in place on the nozzle assembly 36 by a retainer 58. The exit orifice and wear pad inserts can be manufactured in the shape of simple cylindrical and disc shapes. Also, the retainer 58 may have an oversized ID which results in a significant reduction in the accumulation of liquid/slurry deposits on the exterior surface of the nozzle assembly 36. The atomizer 5 secures the outer barrel 10 to the inner barrel 12 at an end opposite the atomizer housing 30 through the use of packing 40, a follower ring 42, a packing gland 44 and a packing gland nut 46. The impact of the three-phase mixture of gas, liquid, and solid particles into the surface of the wear plug 32 results in the further break-up of liquid droplets and any agglomerated solid particles therein, ensuring complete homogenization of the three-phase mixture. Immediately following impact into the surface of the wear plug 32, the three-phase mixture turns 90 degrees and exits the secondary mix chamber wear sleeve 24 through port 28 where it is directed into the perpendicular orifice 34 which is located perpendicular to the secondary mix chamber wear sleeve 24. The three-phase mixture enters reservoir 50 at the end of the perpendicular orifice 34, where the liquid phase is further atomized into a fine mist with a homogeneous distribution of solids particles by impacting the mixture against exit wear pad 52 located at reservoir 50. By utilizing a plurality of exit orifices 54 on the nozzle assembly 36, the present invention permits the discharge of a plurality of jets of three-phase mixture through each port 56 of the exit orifices 54 after collection in the reservoir 50 and contact against the exit wear pad 52. Oversized particles that are contained in the slurry 6, from whatever source, are able to flow through all ports without obstruction. All ports allow for low internal velocities, thereby minimizing both internal pressure losses and erosion. Of course, ports 56 operate at high velocity to produce atomization. The configuration of the atomizer 5 facilitates the use of corrosion/erosion resistant materials, especially for the perpendicular orifice 34 and exit orifices 54 where velocities cannot be held below the threshold of erosion. The wetted surfaces of the known internal mix dual-fluid atomizers are subjected to an extremely harsh operating environment due to the turbulent conditions created internally beginning at entry point where the atomizing gas and liquid or slurry are first combined together and ending at exit points for discharge. The operating pressure versus flow relationship and atomization performance characteristics of the dual-fluid atomizers are effected by dimensional changes of the internal wetted surfaces. As the wetted surfaces wear, especially the inner diameter of the discharge or exit orifice, atomization quality typically deteriorates to the point where process operations may be adversely effected, thus necessitating atomizer replacement. Furthermore, excessive internal wear may occur to the point of catastrophic atomizer failure. Until now, the use of corrosion/erosion resistant materials to protect the wetted surfaces of internal mix dual-fluid atomizers for the purpose of extending the useful wear life while simultaneously reducing overall operating and maintenance requirements has been limited by design and/or manufacturing costs/considerations. The present invention permits the use of replaceable corrosion/erosion resistant wear components manufactured in the form of simple shapes which are used to fully line the internal wetted surfaces of the right angle, multiple exit orifice dual-fluid atomizer 5 in order to extend its useful life while simultaneously reducing overall operating and maintenance requirements. The manufacture and machining of many corrosion/erosion resistant materials such as certain alloys and ceramics can be very costly. By limiting the configuration of the primary mix chamber wear sleeve 22, secondary mix chamber wear sleeve 24, perpendicular orifice insert 34, wear plug insert 32, wear pad insert 52, and exit orifice inserts 55 to that of simple cylindrical and disc shapes, not only can 100% lining of the internal wetted surfaces from the initial mix point to the point of discharge be achieved but also the difficulty and associated high costs to manufacture these components can be minimized. The useful service life of the exit orifice insert 55 is significantly increased over that of the known designs through the addition of the straight section 57 located immediately downstream of the inwardly tapering inlet end of the exit orifice insert 55. The major advantage over that of the known designs are improved wear characteristics resulting in an increase in the useful service life of the atomizer 5. With the other configurations, once the minor diameter (i.e. the point where the inwardly tapering inlet and the outwardly tapering outlet begins) of the exit orifice increases in diameter due to the corrosive/erosive nature of the atomized fluid, atomization performance characteristics begin to deteriorate. For the present invention, the mix chamber inner diameter 13 is sized to maintain the velocity of the three-phase mixture of the atomizing gas, liquid, and solids in the range of 50 to 400 ft./sec. and preferably at a velocity of 200 ft./sec. The inner diameter of the secondary mix chamber wear sleeve discharge port 28 is sized to maintain the velocity of the three-phase mixture of the atomizing gas, liquid, and solids in a range of 150 to 700 ft./sec. and preferably at a velocity of 400 ft./sec. The mix chamber housing 18 connects two cylinders, i.e. sleeves 22 and 24 open at both ends with atomizing gas ports 20 located around its periphery. The effective length of the mix chamber 13 is defined as the distance between the point at which the centerline of the atomizing gas port 20 intersects the axial centerline of the mix chamber 13 to the point where the centerline of the discharge port 28 intersects perpendicular to the axial centerline of the mix chamber 13. The overall combined effective length of both the primary and secondary mix chamber wear sleeves 22 and 24 may be from 1.0 to 10.0 times the mix chamber internal diameter 13 with the optimum length being within a range of 2.0 to 5.0 times the mix chamber 13 internal diameter. The atomizing gas inlets 20 into the mix chamber 13 are one or more annulus, or a series of one or more holes, located not more than nine nor less than one mix chamber inner diameter upstream of the centerline of the secondary mix chamber sleeve discharge port 28. The direction of the ports must be greater than 15 degrees and not more than 90 degrees. The size of the ports is adjusted to keep the atomizing gas within the range of 100 to 700 ft./sec. The optimum number of atomizing gas ports 20 is three to four which allows for large passageways to prevent clogging by particles entrained in the atomizing gas, but still maintains balanced mixing of the atomizing gas with the fluid. The fluid entrance port 15 in the mix chamber housing 18 is located along the axial centerline of the primary and secondary mix chamber wear sleeves 22 and 24 at the end opposite the discharge port 28. The fluid inlet must be a minimum of 0.25 times the mix chamber inner diameter upstream of the atomizing gas inlet ports 20. The size of the fluid inlet port 15 must be such so as to maintain the fluid velocity in the range of 0.5 to 40 ft./sec. The major diameter of the outwardly tapering discharge of reservoir 50 of the perpendicular orifice insert 34 must be such that it is equal to the diameter of the bolt circle that defines the centerline of the entrance of the exit orifices 54 plus the minor diameter of the exit orifice 54. The minor diameter of the perpendicular orifice insert 34 is set less than or equal to the inner diameter of the secondary mix chamber discharge port 28 such that the velocity of the three-phase mixture is maintained in the range of 150 to 700 ft./sec. The height of the outwardly tapering discharge of reservoir 50 of the perpendicular orifice insert 34 must be in the range of 0.1 to 6 of the perpendicular orifice insert 34 inner diameters. The minor inner diameter of the exit orifices 54 is adjusted to meet capacity requirements. The velocity must be maintained at the critical velocity of the two or three-phase mixture. The diameter and included angle of spray are set to meet design needs. The inlet radius may be from 2 to 10 times the minor inner diameter of the exit orifice 54. The length of the straight section may be from 0.25 to 5.0 times the minor inner diameter of the exit orifice 54 with the optimum length being in the range of 1.0 to 2.0 times the minor inner diameter. The included angle of the discharge port 56 must be in the range of 3 to 14 degrees. The inlets of the exit orifices 54 must be positioned in the nozzle assembly 36 such that they are located on a circle centered on the axis of the atomizer housing 30 having a diameter which is equal to or greater than the sum of the perpendicular orifice insert 34 diameter plus the exit orifice minor inner diameter. Preferably, the outer diameter of the exit orifice inserts 55 must be such that when the exit orifice inserts 55 are installed in the nozzle assembly 36 they are tangential to one another. This works well providing the number of exit orifices 54 is equal to or greater than five. For applications where the number of exit orifice inserts 55 is less than five, the tangential arrangement of the exit orifice insert 55 becomes either impossible or impractical to achieve. In order to circumvent this problem, a combination of wear shields (not shown) and exit orifice inserts 55, preferably of equal outer diameter, may be installed in the nozzle assembly 36 to achieve the desired tangential arrangement of corrosion/erosion resistant wear materials and line most of the internal wetted surfaces of the nozzle assembly 36. The outer diameter of the wear pad 52 must be such that when it is installed in the nozzle assembly 36, it is tangential to the outer diameter of the exit orifice inserts 55. Major advantages for the present invention include the following: the configuration of the present invention permits the co-current or countercurrent injection of an atomized liquid, solution, dry powder, or slurry into a gas stream flowing perpendicular or near perpendicular to the central axis (i.e. center line of the inner/outer barrels) of the atomizer; the configuration of the present invention permits the homogeneous mixing of the gas, liquid and/or solid particles to take place along the central axis (i.e. center line of the inner/outer barrels) of the atomizer before discharging at a right angle with respect to the central axis, thus minimizing the overall profile of the atomizer head; the configuration of the present invention permits the simple replacement of all internal wetted wear components; there is an improved exit orifice insert wear life resulting from lengthening the flow path of the minor diameter, the exterior shape of the exit orifice inserts, primary and secondary mix chamber wear sleeves, wear plug and wear pad are those of simple cylindrical and disc shapes, thus minimizing manufacturing costs; the tangential arrangement of the corrosion/erosion resistant low pressure drop exit orifice and wear pad inserts minimizes the amount of metal substrate (i.e. base end cap material) exposed to the atomized fluid thus extending the useful service life of the atomizer end cap assembly; enlargement of the exit orifice insert retainer inner diameter reduces/eliminates the interference of the retainer inner diameter with the atomized jets resulting in a significant reduction in the accumulation of liquid/slurry deposits on the exterior surface of the nozzle assembly; and the included angle of spray may be varied from 20 degrees to 160 degrees. While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
A dual-fluid low pressure drop atomizer utilizes extended wear life material and comprises a nozzle head having a chamber therein for receiving a mixture of a first compressible fluid and a second fluid containing solids. The nozzle head also has an orifice therein communicating with and adjacent to the mix chamber for discharging jets of the mixture. The orifice and the mix chamber form an approximate right angle therebetween. An inner barrel is connected to the nozzle head at the mix chamber and supplies the first fluid to the nozzle head. An outer barrel is arranged around the inner barrel creating an annulus therebetween and is also connected to the nozzle head for supplying the second fluid to the nozzle head. Wear resistant material provided in the mix chamber reduces erosion within the atomizer head. A plurality of ports are provided in the nozzle head and communicate with the orifice for discharging a jet at a multiplicity of locations.
Concisely explain the essential features and purpose of the invention.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates, in general, to atomizers and, in particular, to a new and useful dual-fluid atomizer having a unique multiple exit orifice and replaceable wear materials.", "Description of the Related Art Generally, there are many types of atomizers that have been developed in order to atomize a fluid medium into a mist of fine particle size.", "Most atomizer designs are classified in one of the following categories: 1) hydraulic or mechanical atomizers wherein atomization is accomplished by discharging a fluid at high pressure through an orifice;", "2) dynamic atomizers such as a high speed rotary disk or cup;", "and 3) dual-fluid atomizers in which fluid atomization is achieved by combining a liquid with a compressed gas such as air or steam.", "Dual-fluid atomizers are further subdivided into two basic types, depending on the location where the atomizing gas and liquid are mixed, i.e. external to the atomizer or internal to the atomizer.", "With external mix dual-fluid atomizers, the gas and liquid streams are mixed external to the atomizer housing by impinging one jet against the other.", "With internal mix dual-fluid atomizers, the atomizing gas and liquid streams are mixed internal to the atomizer and discharged through single or multiple exit orifices.", "For erosive applications where particle-laden liquids, i.e. slurries, are the atomized fluid, the type of atomizer is limited by practical constraints.", "These constraints include flow capacity, the required size of droplets in the atomized spray (i.e. particle size distribution), the size of internal flow passages, the physical durability of the atomizer components (i.e. service life), the atomizers sensitivity with respect to the degradation of performance due to dimensional change caused by the corrosive and/or erosive nature of the fluid to be atomized, and commercially acceptable energy requirements to produce the atomized spray.", "There are many different internal mix dual-fluid atomizers that have been developed.", "U.S. Pat. Nos. 4,819,878 and 5,129,583 disclose two types of dual-fluid atomizers which are currently used.", "SUMMARY OF THE INVENTION The present invention is an extended wear life, low pressure drop, right angle, multiple exit orifice dual-fluid atomizer which utilizes replaceable wear materials.", "The unique arrangement of the present invention includes large size internal flow passages which allow for the passage of grit or other relatively large particles without clogging and at the same time produces fine atomization of the liquid fraction.", "The present invention also facilitates the use of corrosion/erosion resistant materials which fully line the internal wetted surfaces of the atomizer for extending the useful wear life of the atomizer while simultaneously reducing overall operating and maintenance requirements.", "The present invention utilizes a gas such as compressed air or steam as the atomizing medium to produce a homogeneous mixture of finely atomized liquid droplets containing a uniform dispersion of solids.", "Where a liquid is not utilized, the present invention produces a fine distribution of powder particles.", "The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure.", "For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawing and descriptive matter in which preferred embodiments of the invention are illustrated.", "BRIEF DESCRIPTION OF THE DRAWINGS In the drawing: FIG. 1 is a sectional view of a dual-fluid atomizer according to the present invention;", "and FIG. 2 is an enlarged view of the atomizer head of FIG. 1. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention, as illustrated in FIG. 1, is a dual-fluid atomizer, generally designated 5, comprising an outer barrel 10 having an inner barrel 12 disposed therein and defining an annular space 11 therebetween.", "The inner barrel 12 has a port or opening 14 at one end for the entry of a slurry, solution, liquid or dry powder flow 6.", "The outer barrel 10 has an opening 16 for a gas, air or steam flow 8 which flows through annulus 11.", "The outer barrel 10 and the inner barrel 12 are connected to a mix chamber housing 18 of an atomizer housing 30.", "The outer barrel 10 and the inner barrel 12 are connected to the chamber housing 18 at their ends opposite openings 16 and 14, respectively.", "When the present invention is used in a preferred embodiment for atomizing a slurry, chamber housing 18 has an opening 15 which permits the entry of the slurry flow 6 into a primary mix chamber wear sleeve 22 and a secondary mix chamber wear sleeve 24 of the chamber housing 18.", "Adaptor coupling 26 secures the atomizer housing 30, the mix chamber housing 18 and outer barrel 10.", "Inner barrel 12 directs the slurry 6 at low velocities to the inlet of the primary mix chamber wear sleeve 22 where it is initially mixed with atomizing gas 8 provided by outer barrel 10 which enters through gas ports 20 in the primary mix chamber wear sleeve 22.", "In the primary mix chamber wear sleeve 22, a three-phase homogeneous mixture of gas, liquid and solid particles flow therethrough and into the secondary mix chamber wear sleeve 24 wherein it impacts a wear plug 32 located at one end of the secondary mix chamber wear sleeve 24 within the atomizer housing 30.", "Sleeves 22 and 24 and wear plug 32 as well as inserts 34 are made of a wear-resistant material such as ceramic material.", "The homogeneous mixture is then directed to an inlet 28 of a perpendicular orifice insert 34 in the atomizer housing 30.", "As illustrated in FIG. 2, perpendicular orifice insert 34 has a reservoir 50 at an end opposite the port 28.", "The three-phase mixture flows through the perpendicular orifice insert 34 and into the reservoir 50 which is a conical-shaped reservoir formed by the perpendicular orifice insert 34 and nozzle assembly 36.", "At the downstream end of the reservoir 50, a wear pad 52 is located which is also located adjacent orifices 54.", "The three-phase mixture impacts into the wear pad 52 at the reservoir 50 which results in a further homogenization of the mixture prior to discharge.", "The homogenized slurry is then discharged through exit orifices 54 in the nozzle assembly 36.", "The exit orifices 54 located in the assembly 36 communicate with the reservoir 50 for discharging the mixture as an atomized fine mist with a homogeneous distribution of solid particles as it exits through ports 56 located at the end of orifices 54.", "The exit orifices 54 are holes which are bored through exit orifice inserts 55 which can be made from wear resistant material and preferably touch tangent to each other and are inserted into the nozzle assembly 36 and are maintained in place on the nozzle assembly 36 by a retainer 58.", "The exit orifice and wear pad inserts can be manufactured in the shape of simple cylindrical and disc shapes.", "Also, the retainer 58 may have an oversized ID which results in a significant reduction in the accumulation of liquid/slurry deposits on the exterior surface of the nozzle assembly 36.", "The atomizer 5 secures the outer barrel 10 to the inner barrel 12 at an end opposite the atomizer housing 30 through the use of packing 40, a follower ring 42, a packing gland 44 and a packing gland nut 46.", "The impact of the three-phase mixture of gas, liquid, and solid particles into the surface of the wear plug 32 results in the further break-up of liquid droplets and any agglomerated solid particles therein, ensuring complete homogenization of the three-phase mixture.", "Immediately following impact into the surface of the wear plug 32, the three-phase mixture turns 90 degrees and exits the secondary mix chamber wear sleeve 24 through port 28 where it is directed into the perpendicular orifice 34 which is located perpendicular to the secondary mix chamber wear sleeve 24.", "The three-phase mixture enters reservoir 50 at the end of the perpendicular orifice 34, where the liquid phase is further atomized into a fine mist with a homogeneous distribution of solids particles by impacting the mixture against exit wear pad 52 located at reservoir 50.", "By utilizing a plurality of exit orifices 54 on the nozzle assembly 36, the present invention permits the discharge of a plurality of jets of three-phase mixture through each port 56 of the exit orifices 54 after collection in the reservoir 50 and contact against the exit wear pad 52.", "Oversized particles that are contained in the slurry 6, from whatever source, are able to flow through all ports without obstruction.", "All ports allow for low internal velocities, thereby minimizing both internal pressure losses and erosion.", "Of course, ports 56 operate at high velocity to produce atomization.", "The configuration of the atomizer 5 facilitates the use of corrosion/erosion resistant materials, especially for the perpendicular orifice 34 and exit orifices 54 where velocities cannot be held below the threshold of erosion.", "The wetted surfaces of the known internal mix dual-fluid atomizers are subjected to an extremely harsh operating environment due to the turbulent conditions created internally beginning at entry point where the atomizing gas and liquid or slurry are first combined together and ending at exit points for discharge.", "The operating pressure versus flow relationship and atomization performance characteristics of the dual-fluid atomizers are effected by dimensional changes of the internal wetted surfaces.", "As the wetted surfaces wear, especially the inner diameter of the discharge or exit orifice, atomization quality typically deteriorates to the point where process operations may be adversely effected, thus necessitating atomizer replacement.", "Furthermore, excessive internal wear may occur to the point of catastrophic atomizer failure.", "Until now, the use of corrosion/erosion resistant materials to protect the wetted surfaces of internal mix dual-fluid atomizers for the purpose of extending the useful wear life while simultaneously reducing overall operating and maintenance requirements has been limited by design and/or manufacturing costs/considerations.", "The present invention permits the use of replaceable corrosion/erosion resistant wear components manufactured in the form of simple shapes which are used to fully line the internal wetted surfaces of the right angle, multiple exit orifice dual-fluid atomizer 5 in order to extend its useful life while simultaneously reducing overall operating and maintenance requirements.", "The manufacture and machining of many corrosion/erosion resistant materials such as certain alloys and ceramics can be very costly.", "By limiting the configuration of the primary mix chamber wear sleeve 22, secondary mix chamber wear sleeve 24, perpendicular orifice insert 34, wear plug insert 32, wear pad insert 52, and exit orifice inserts 55 to that of simple cylindrical and disc shapes, not only can 100% lining of the internal wetted surfaces from the initial mix point to the point of discharge be achieved but also the difficulty and associated high costs to manufacture these components can be minimized.", "The useful service life of the exit orifice insert 55 is significantly increased over that of the known designs through the addition of the straight section 57 located immediately downstream of the inwardly tapering inlet end of the exit orifice insert 55.", "The major advantage over that of the known designs are improved wear characteristics resulting in an increase in the useful service life of the atomizer 5.", "With the other configurations, once the minor diameter (i.e. the point where the inwardly tapering inlet and the outwardly tapering outlet begins) of the exit orifice increases in diameter due to the corrosive/erosive nature of the atomized fluid, atomization performance characteristics begin to deteriorate.", "For the present invention, the mix chamber inner diameter 13 is sized to maintain the velocity of the three-phase mixture of the atomizing gas, liquid, and solids in the range of 50 to 400 ft.", "/sec.", "and preferably at a velocity of 200 ft.", "/sec.", "The inner diameter of the secondary mix chamber wear sleeve discharge port 28 is sized to maintain the velocity of the three-phase mixture of the atomizing gas, liquid, and solids in a range of 150 to 700 ft.", "/sec.", "and preferably at a velocity of 400 ft.", "/sec.", "The mix chamber housing 18 connects two cylinders, i.e. sleeves 22 and 24 open at both ends with atomizing gas ports 20 located around its periphery.", "The effective length of the mix chamber 13 is defined as the distance between the point at which the centerline of the atomizing gas port 20 intersects the axial centerline of the mix chamber 13 to the point where the centerline of the discharge port 28 intersects perpendicular to the axial centerline of the mix chamber 13.", "The overall combined effective length of both the primary and secondary mix chamber wear sleeves 22 and 24 may be from 1.0 to 10.0 times the mix chamber internal diameter 13 with the optimum length being within a range of 2.0 to 5.0 times the mix chamber 13 internal diameter.", "The atomizing gas inlets 20 into the mix chamber 13 are one or more annulus, or a series of one or more holes, located not more than nine nor less than one mix chamber inner diameter upstream of the centerline of the secondary mix chamber sleeve discharge port 28.", "The direction of the ports must be greater than 15 degrees and not more than 90 degrees.", "The size of the ports is adjusted to keep the atomizing gas within the range of 100 to 700 ft.", "/sec.", "The optimum number of atomizing gas ports 20 is three to four which allows for large passageways to prevent clogging by particles entrained in the atomizing gas, but still maintains balanced mixing of the atomizing gas with the fluid.", "The fluid entrance port 15 in the mix chamber housing 18 is located along the axial centerline of the primary and secondary mix chamber wear sleeves 22 and 24 at the end opposite the discharge port 28.", "The fluid inlet must be a minimum of 0.25 times the mix chamber inner diameter upstream of the atomizing gas inlet ports 20.", "The size of the fluid inlet port 15 must be such so as to maintain the fluid velocity in the range of 0.5 to 40 ft.", "/sec.", "The major diameter of the outwardly tapering discharge of reservoir 50 of the perpendicular orifice insert 34 must be such that it is equal to the diameter of the bolt circle that defines the centerline of the entrance of the exit orifices 54 plus the minor diameter of the exit orifice 54.", "The minor diameter of the perpendicular orifice insert 34 is set less than or equal to the inner diameter of the secondary mix chamber discharge port 28 such that the velocity of the three-phase mixture is maintained in the range of 150 to 700 ft.", "/sec.", "The height of the outwardly tapering discharge of reservoir 50 of the perpendicular orifice insert 34 must be in the range of 0.1 to 6 of the perpendicular orifice insert 34 inner diameters.", "The minor inner diameter of the exit orifices 54 is adjusted to meet capacity requirements.", "The velocity must be maintained at the critical velocity of the two or three-phase mixture.", "The diameter and included angle of spray are set to meet design needs.", "The inlet radius may be from 2 to 10 times the minor inner diameter of the exit orifice 54.", "The length of the straight section may be from 0.25 to 5.0 times the minor inner diameter of the exit orifice 54 with the optimum length being in the range of 1.0 to 2.0 times the minor inner diameter.", "The included angle of the discharge port 56 must be in the range of 3 to 14 degrees.", "The inlets of the exit orifices 54 must be positioned in the nozzle assembly 36 such that they are located on a circle centered on the axis of the atomizer housing 30 having a diameter which is equal to or greater than the sum of the perpendicular orifice insert 34 diameter plus the exit orifice minor inner diameter.", "Preferably, the outer diameter of the exit orifice inserts 55 must be such that when the exit orifice inserts 55 are installed in the nozzle assembly 36 they are tangential to one another.", "This works well providing the number of exit orifices 54 is equal to or greater than five.", "For applications where the number of exit orifice inserts 55 is less than five, the tangential arrangement of the exit orifice insert 55 becomes either impossible or impractical to achieve.", "In order to circumvent this problem, a combination of wear shields (not shown) and exit orifice inserts 55, preferably of equal outer diameter, may be installed in the nozzle assembly 36 to achieve the desired tangential arrangement of corrosion/erosion resistant wear materials and line most of the internal wetted surfaces of the nozzle assembly 36.", "The outer diameter of the wear pad 52 must be such that when it is installed in the nozzle assembly 36, it is tangential to the outer diameter of the exit orifice inserts 55.", "Major advantages for the present invention include the following: the configuration of the present invention permits the co-current or countercurrent injection of an atomized liquid, solution, dry powder, or slurry into a gas stream flowing perpendicular or near perpendicular to the central axis (i.e. center line of the inner/outer barrels) of the atomizer;", "the configuration of the present invention permits the homogeneous mixing of the gas, liquid and/or solid particles to take place along the central axis (i.e. center line of the inner/outer barrels) of the atomizer before discharging at a right angle with respect to the central axis, thus minimizing the overall profile of the atomizer head;", "the configuration of the present invention permits the simple replacement of all internal wetted wear components;", "there is an improved exit orifice insert wear life resulting from lengthening the flow path of the minor diameter, the exterior shape of the exit orifice inserts, primary and secondary mix chamber wear sleeves, wear plug and wear pad are those of simple cylindrical and disc shapes, thus minimizing manufacturing costs;", "the tangential arrangement of the corrosion/erosion resistant low pressure drop exit orifice and wear pad inserts minimizes the amount of metal substrate (i.e. base end cap material) exposed to the atomized fluid thus extending the useful service life of the atomizer end cap assembly;", "enlargement of the exit orifice insert retainer inner diameter reduces/eliminates the interference of the retainer inner diameter with the atomized jets resulting in a significant reduction in the accumulation of liquid/slurry deposits on the exterior surface of the nozzle assembly;", "and the included angle of spray may be varied from 20 degrees to 160 degrees.", "While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles." ]
FIELD OF INVENTION This invention relates to an airstream ionizer for neutralizing static charge on objects within the airstream, and more particularly, to a circuit which automatically and passively causes the unit to emit equal amounts of positive and negative ions creating an ion balance in the air stream exiting the unit. BACKGROUND OF INVENTION Air ionizers which emit a flow of positively and negatively charged ions have to date, proven most effective in neutralizing accumulated static charge on a non-conductive object within the ionized airstream. Typically, airstream ionizers place a high voltage potential on one or more emitter points to initiate the ionization process or corona, in the hopes of emitting an airstream containing an equal number of positive and negative ions. Measurements have shown, however, that various factors influence the generation of a balanced ion stream and cause the ionizer to output an airstream which is itself charged. For example, the greater mobility of negative ions, and ground planes formed by the metal case of the ionizer in close proximity to the emitters, cause an imbalance in the positive and negative ions emitted by the ionizer. This charge imbalance is subsequently transferred to any object in the path of the airstream, thereby adding to the problem that the air ionizer was designed to eliminate. In addition, dirt on the emitter points as well as humidity in the air affect the ionization process. Various mechanical techniques are known to balance the production of positive and negative ions delivered by the ionizer at a given moment under given conditions. Such techniques include adjusting the position of the emitters relative to the collector or using external sensors and feedback mechanisms. However, continuously changing environmental conditions as well as the constant accumulation of dirt on the emitters make these approaches ineffective. Attempts have been made to achieve a passively balanced ionized air stream by causing the ion emitters to give off positive and negative ions equally. In such a system, the one or more emitter points are capacitively isolated from the high side of an AC power source. Although negative ions are generally easier to produce and can be produced at lower voltages because of the physics involved in air ionization, a system utilizing capacitively coupled emitters overcomes this excess negative ion production. In such a system, the emitter points become slightly positively charged. This positive charge adds algebraically to the positive charge present during the positive going portion of the AC waveform, thus producing more positive ions. The increased production of positive ions continues until an equal number of positive and negative ions are generated. Even though the emitter circuit is now generating a balanced amount of positive and negative ions, it has been found that the charge of the ionized airstream exiting the ionizer is not balanced. SUMMARY OF INVENTION It is therefore an object of this invention to provide an automatically self-balancing air ionizer which emits a truly balanced ionized airstream under all operating conditions. It is a further object of this invention to provide a self-balancing air ionizer which balances the ion collection to insure constant ion balance in the air stream. It is a still further object of this invention to provide a reliable self-balancing air ionizer which passively balances the ionized airstream thereby reducing the cost and complexity of the system. This invention results from the realization that ions exiting an air ionizer are collected unevenly, thus introducing an imbalance in the ionized airstream, and from the further realization that in order to balance an ion collector circuit, the collector circuit must be isolated from all external sources or sinks of charge, thereby preventing an excess of positive or negative charge from building up in the circuit and subsequently being emitted into the airstream. This invention features a self-balancing circuit for convection air ionizers including one or more ion emitter points and an ion collector. The emitter points and the collector are isolated from external charge sources and sinks for maintaining balance in the positive and negative charge emitted from the emitter points and collected by the collector, for maintaining a charge balanced ionized airstream. In one embodiment, the emitter points and collector are isolated from external charge sources and sinks by a first capacitor means in series with the emitter points. Also included is a second capacitor in series with the collector and ground. Alternatively, the air ionizer may include a circuit in which the emitter points and collector are united in one ungrounded circuit and a capacitor isolates the emitter points and collector from external charge sources of sinks for maintaining charge balance. In addition, an isolation transformer isolates the AC power source from the emitter and collector circuit. DESCRIPTION OF PREFERRED EMBODIMENT Other objects, features and advantages will occur from the following description of a preferred embodiment and the accompanying drawings, in which: FIG. 1 is a block diagram of a self-balancing air ionizer according to this invention. FIG. 2 is a schematic representation of a self-balancing ion emitter and collector according to this invention; FIG. 3 is a schematic view of an another embodiment of a balanced air ionizer according to the present invention using only a single capacitor; and FIG. 4 is a schematic representation of yet another embodiment of a balanced air ionizer according to the present invention with separate positive and negative emitters. A self-balancing air ionizer according to this invention may be accomplished by providing an energy source for placing a voltage potential between one or more ion emitter points and an ion collector. A fan or other airflow device provides an airstream flowing past the ion emitter points and ion collector. The air ionizer also includes isolation means for isolating the emitter points and the collector from external charge sources, for maintaining a balanced positive and negative ionized air stream. The isolation means may include capacitor means in series with the emitter and with the collector. Alternatively, the capacitor means may be placed between an ungrounded emitter-collector circuit and ground. The isolation means may also include an isolation transformer as well as a non-metallic air ionizer enclosure. A self-balancing air ionizer 10. FIG. 1, includes energy source 12 which provides a voltage potential between emitter points 14 and collector 16 to promote ionization. Air flow source 15 provides a constant source of air 17 flowing past emitter points 14 and collector 16. Airflow 17 is directed towards charged object 19, whose static charge is to be neutralized. Isolation means 13 isolates emitter points 14 and collector 16 from energy source 12 as well as other external charge sources or sinks. Isolation means 13 may also include insulative enclosure 23 which completely surrounds emitters 14 and collector 16 to prevent any object near the ionizer from acting as an unwanted ion collector. A self-balancing air ionizer circuit 20, FIG. 2, includes AC power source 12 for providing a high voltage potential of typically 5000 volts between emitter points 14 and collector 16. Primary collector 16 may be a solid sheet of metal material placed near the ion emitter and parallel with the airflow so as not to interfere with the airflow characteristics. In addition, collector 16 may be any surface within the unit that airborne ions give up their charge to. First capacitor 24 is in series with emitter points 14 and secondary winding 22 of transformer 25; while second capacitor 26 is connected in series between collector 16 and ground. AC power source 12 is connected to primary winding 18 of transformer 25. Secondary winding 22 charges capacitor 24 and places a voltage potential between emitter points 14 and collector 16. Between primary winding 18 and secondary winding is transformer core 21. Air has naturally occurring positive and negative ions in equal numbers, and is therefore normally in a balanced condition. Placing a high voltage potential between emitter points 14 and collector 16, however, initiates ionization. This ionization process occurs when a voltage potential is placed between two adjacent locations. Once ionization is initiated, the accelerated movement of the ions or free electrons during their attraction and repulsion from the charged emitter points and collector, causes them to collide with other molecules, thus creating more ions. This avalanche effect continues up to a maximum limit. Insuring that an equal number of ions are produced by emitter 14, however, does not insure that an equal number of positive and negative ions are emitted into the airstream. Since the ions must travel past collector 16 when exiting the ionizer, most ions are lost to the oppositely charged collector. Further, since negative ions are more mobile, it has been found that if the collector is held at ground potential, more negative ions are lost to the collector than positive ions. By providing capacitor 26 in the collector circuit, the capacitor stores the negative charge and attracts more positive ions and repels more negative ions until a balance is achieved. Balancing of the ions emitted and lost to the collector plate takes place over a minimum number of cycles with a steady state condition being achieved within a few seconds time. An additional embodiment of a self-balancing air ionizer circuit 30, FIG. 3, includes AC power source 12, primary winding 18 and secondary winding 22. Secondary winding 22 is isolated from transformer core 21. Ion emitter point 14a and collector 16 are connected directly to secondary winding 22 of transformer 25. To prevent any extraneous charges from entering the circuit from ground which would unbalance the ionized airstream, capacitor 28 is connected between the circuit and ground. In this way, no charge may flow to an adjoining grounded point such as might occur between the transformer high voltage windings and the transformer core, if the voltage on the windings near the core exceed the isolation value of the transformer. Any imbalance in the circuit results in a charge stored on capacitor 28 and serves as a restoring force or negative feedback during the next AC cycle of opposite polarity. Another embodiment of a self-balancing air ionizer circuit 40, FIG. 4, includes AC power source 12 and transformer 25 having primary winding 18 and secondary winding 22. Although similar in operation to the circuit in FIG. 1, rectifier diode 34 allows emitter points 14c to charge positively during the positive cycle of the AC wave form; while rectifier diode 36 allows emitter points 14b to charge negatively during the negative cycle of the AC wave form. Capacitors 24 and 26 serve to balance the ion production and collection of emitters 14b and 14c as well as collector 16. Since emitters 14b, 14c and collector 16 are isolated from other ambient conducting sources or sinks, any net charge exiting by means of the front air exit results in a restoring force or feedback charge accumulating on capacitors 24 or 26, and no net charge flows to or from ground. Capacitors 31 and 32 serve to filter or smooth out the rectified voltage applied to positive emitters 14c and negative emitters 14b. Although specific features of the invention are shown in some drawings and not others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. Other embodiments will occur to those skilled in the art and are within the following claims:
A self-balancing circuit for convection air ionizers with a passively balanced ion emitter and collector including a circuit in which the ion emitter and the collector are capacitively isolated from external charge sources or sinks for maintaining balance in the positive and negative charge for producing a zero average current flow and a charge balanced ionized airstream.
Identify and summarize the most critical features from the given passage.
[ "FIELD OF INVENTION This invention relates to an airstream ionizer for neutralizing static charge on objects within the airstream, and more particularly, to a circuit which automatically and passively causes the unit to emit equal amounts of positive and negative ions creating an ion balance in the air stream exiting the unit.", "BACKGROUND OF INVENTION Air ionizers which emit a flow of positively and negatively charged ions have to date, proven most effective in neutralizing accumulated static charge on a non-conductive object within the ionized airstream.", "Typically, airstream ionizers place a high voltage potential on one or more emitter points to initiate the ionization process or corona, in the hopes of emitting an airstream containing an equal number of positive and negative ions.", "Measurements have shown, however, that various factors influence the generation of a balanced ion stream and cause the ionizer to output an airstream which is itself charged.", "For example, the greater mobility of negative ions, and ground planes formed by the metal case of the ionizer in close proximity to the emitters, cause an imbalance in the positive and negative ions emitted by the ionizer.", "This charge imbalance is subsequently transferred to any object in the path of the airstream, thereby adding to the problem that the air ionizer was designed to eliminate.", "In addition, dirt on the emitter points as well as humidity in the air affect the ionization process.", "Various mechanical techniques are known to balance the production of positive and negative ions delivered by the ionizer at a given moment under given conditions.", "Such techniques include adjusting the position of the emitters relative to the collector or using external sensors and feedback mechanisms.", "However, continuously changing environmental conditions as well as the constant accumulation of dirt on the emitters make these approaches ineffective.", "Attempts have been made to achieve a passively balanced ionized air stream by causing the ion emitters to give off positive and negative ions equally.", "In such a system, the one or more emitter points are capacitively isolated from the high side of an AC power source.", "Although negative ions are generally easier to produce and can be produced at lower voltages because of the physics involved in air ionization, a system utilizing capacitively coupled emitters overcomes this excess negative ion production.", "In such a system, the emitter points become slightly positively charged.", "This positive charge adds algebraically to the positive charge present during the positive going portion of the AC waveform, thus producing more positive ions.", "The increased production of positive ions continues until an equal number of positive and negative ions are generated.", "Even though the emitter circuit is now generating a balanced amount of positive and negative ions, it has been found that the charge of the ionized airstream exiting the ionizer is not balanced.", "SUMMARY OF INVENTION It is therefore an object of this invention to provide an automatically self-balancing air ionizer which emits a truly balanced ionized airstream under all operating conditions.", "It is a further object of this invention to provide a self-balancing air ionizer which balances the ion collection to insure constant ion balance in the air stream.", "It is a still further object of this invention to provide a reliable self-balancing air ionizer which passively balances the ionized airstream thereby reducing the cost and complexity of the system.", "This invention results from the realization that ions exiting an air ionizer are collected unevenly, thus introducing an imbalance in the ionized airstream, and from the further realization that in order to balance an ion collector circuit, the collector circuit must be isolated from all external sources or sinks of charge, thereby preventing an excess of positive or negative charge from building up in the circuit and subsequently being emitted into the airstream.", "This invention features a self-balancing circuit for convection air ionizers including one or more ion emitter points and an ion collector.", "The emitter points and the collector are isolated from external charge sources and sinks for maintaining balance in the positive and negative charge emitted from the emitter points and collected by the collector, for maintaining a charge balanced ionized airstream.", "In one embodiment, the emitter points and collector are isolated from external charge sources and sinks by a first capacitor means in series with the emitter points.", "Also included is a second capacitor in series with the collector and ground.", "Alternatively, the air ionizer may include a circuit in which the emitter points and collector are united in one ungrounded circuit and a capacitor isolates the emitter points and collector from external charge sources of sinks for maintaining charge balance.", "In addition, an isolation transformer isolates the AC power source from the emitter and collector circuit.", "DESCRIPTION OF PREFERRED EMBODIMENT Other objects, features and advantages will occur from the following description of a preferred embodiment and the accompanying drawings, in which: FIG. 1 is a block diagram of a self-balancing air ionizer according to this invention.", "FIG. 2 is a schematic representation of a self-balancing ion emitter and collector according to this invention;", "FIG. 3 is a schematic view of an another embodiment of a balanced air ionizer according to the present invention using only a single capacitor;", "and FIG. 4 is a schematic representation of yet another embodiment of a balanced air ionizer according to the present invention with separate positive and negative emitters.", "A self-balancing air ionizer according to this invention may be accomplished by providing an energy source for placing a voltage potential between one or more ion emitter points and an ion collector.", "A fan or other airflow device provides an airstream flowing past the ion emitter points and ion collector.", "The air ionizer also includes isolation means for isolating the emitter points and the collector from external charge sources, for maintaining a balanced positive and negative ionized air stream.", "The isolation means may include capacitor means in series with the emitter and with the collector.", "Alternatively, the capacitor means may be placed between an ungrounded emitter-collector circuit and ground.", "The isolation means may also include an isolation transformer as well as a non-metallic air ionizer enclosure.", "A self-balancing air ionizer 10.", "FIG. 1, includes energy source 12 which provides a voltage potential between emitter points 14 and collector 16 to promote ionization.", "Air flow source 15 provides a constant source of air 17 flowing past emitter points 14 and collector 16.", "Airflow 17 is directed towards charged object 19, whose static charge is to be neutralized.", "Isolation means 13 isolates emitter points 14 and collector 16 from energy source 12 as well as other external charge sources or sinks.", "Isolation means 13 may also include insulative enclosure 23 which completely surrounds emitters 14 and collector 16 to prevent any object near the ionizer from acting as an unwanted ion collector.", "A self-balancing air ionizer circuit 20, FIG. 2, includes AC power source 12 for providing a high voltage potential of typically 5000 volts between emitter points 14 and collector 16.", "Primary collector 16 may be a solid sheet of metal material placed near the ion emitter and parallel with the airflow so as not to interfere with the airflow characteristics.", "In addition, collector 16 may be any surface within the unit that airborne ions give up their charge to.", "First capacitor 24 is in series with emitter points 14 and secondary winding 22 of transformer 25;", "while second capacitor 26 is connected in series between collector 16 and ground.", "AC power source 12 is connected to primary winding 18 of transformer 25.", "Secondary winding 22 charges capacitor 24 and places a voltage potential between emitter points 14 and collector 16.", "Between primary winding 18 and secondary winding is transformer core 21.", "Air has naturally occurring positive and negative ions in equal numbers, and is therefore normally in a balanced condition.", "Placing a high voltage potential between emitter points 14 and collector 16, however, initiates ionization.", "This ionization process occurs when a voltage potential is placed between two adjacent locations.", "Once ionization is initiated, the accelerated movement of the ions or free electrons during their attraction and repulsion from the charged emitter points and collector, causes them to collide with other molecules, thus creating more ions.", "This avalanche effect continues up to a maximum limit.", "Insuring that an equal number of ions are produced by emitter 14, however, does not insure that an equal number of positive and negative ions are emitted into the airstream.", "Since the ions must travel past collector 16 when exiting the ionizer, most ions are lost to the oppositely charged collector.", "Further, since negative ions are more mobile, it has been found that if the collector is held at ground potential, more negative ions are lost to the collector than positive ions.", "By providing capacitor 26 in the collector circuit, the capacitor stores the negative charge and attracts more positive ions and repels more negative ions until a balance is achieved.", "Balancing of the ions emitted and lost to the collector plate takes place over a minimum number of cycles with a steady state condition being achieved within a few seconds time.", "An additional embodiment of a self-balancing air ionizer circuit 30, FIG. 3, includes AC power source 12, primary winding 18 and secondary winding 22.", "Secondary winding 22 is isolated from transformer core 21.", "Ion emitter point 14a and collector 16 are connected directly to secondary winding 22 of transformer 25.", "To prevent any extraneous charges from entering the circuit from ground which would unbalance the ionized airstream, capacitor 28 is connected between the circuit and ground.", "In this way, no charge may flow to an adjoining grounded point such as might occur between the transformer high voltage windings and the transformer core, if the voltage on the windings near the core exceed the isolation value of the transformer.", "Any imbalance in the circuit results in a charge stored on capacitor 28 and serves as a restoring force or negative feedback during the next AC cycle of opposite polarity.", "Another embodiment of a self-balancing air ionizer circuit 40, FIG. 4, includes AC power source 12 and transformer 25 having primary winding 18 and secondary winding 22.", "Although similar in operation to the circuit in FIG. 1, rectifier diode 34 allows emitter points 14c to charge positively during the positive cycle of the AC wave form;", "while rectifier diode 36 allows emitter points 14b to charge negatively during the negative cycle of the AC wave form.", "Capacitors 24 and 26 serve to balance the ion production and collection of emitters 14b and 14c as well as collector 16.", "Since emitters 14b, 14c and collector 16 are isolated from other ambient conducting sources or sinks, any net charge exiting by means of the front air exit results in a restoring force or feedback charge accumulating on capacitors 24 or 26, and no net charge flows to or from ground.", "Capacitors 31 and 32 serve to filter or smooth out the rectified voltage applied to positive emitters 14c and negative emitters 14b.", "Although specific features of the invention are shown in some drawings and not others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention.", "Other embodiments will occur to those skilled in the art and are within the following claims:" ]
This is a continuation of application Ser. No. 08/250,550, filed May 27, 1994 now abandoned. FIELD OF THE INVENTION The present invention relates to child carriers attachable to a cart, and in particular, to a child carrier accessory attachable to an ordinary shopping or luggage cart which does not significantly reduce the functionality of the cart. BACKGROUND OF THE INVENTION Shopping carts found in retail establishments generally include a child seat that is part of the rear panel of the shopping cart basket. A back support panel is attached to the rear panel, usually on the inside of the basket, thereby reducing the carrying capacity of the shopping cart. A fold down seat portion traverses the back support panel and the rear panel to form the child set proximate the upper portion of the rear panel. Generally, the child seat is arranged so that the child's legs extend through openings in the back panel. Airport luggage carts have a similar child seat arrangement. However, luggage carts weigh less than a shopping cart and are therefore more prone to tip over. The child seats on shopping or luggage carts only have room for one child. Also, once a child reaches approximately 35 pounds, or is more than approximately 54" tall, the child seat on these carts starts to be too small and uncomfortable for the child. Additionally, children older than approximately 3 years find these seats confining and often attempt to climb out. Consequently, it is very common to see children riding in the basket portion of the shopping cart or standing on the front edge of the lower frame while gripping onto the basket portion, or standing on the luggage portion of a luggage cart. Allowing a child to ride in the basket portion of the shopping cart has proven to be extremely dangerous. The U.S. Consumer Product Safety Commission reported 12,000 hospital emergency room head injuries in 1988 along, to children under 5 years of age primarily due to children falling from shopping carts. Approximately one third of these head injuries were concussions, fractures or internal injuries. (See Consumer Product Safety Alert from the U.S. Consumer Product Safety Commission, March 1990, which is hereby incorporated by reference.) In 1992, the U.S. Consumer Product Safety Commission estimates that 22,920 children were treated in hospital emergency rooms for injuries related to shopping carts. While old style shopping carts were constructed of metal, newer carts are utilizing more plastic parts, including plastic basket portions. Consequently, the center of gravity of newer shopping carts is much lower than the old style metal carts. Since the child seat is generally on the upper portion of the rear panel of the basket portion, a larger child will significantly alter the center of gravity of the cart, especially when the cart is empty. The reported accidents also include injuries resulting from children tipping over the cart by rocking back and forth. There are presently millions of conventional shopping and luggage carts in use. A shopping cart costs anywhere from $70.00 to $120.00. An economically viable solution to child injuries needs to utilize the existing inventory of carts, without significantly reducing the overall functionality of the carts. For example, the solution can not dramatically change the dimensions of the cart. One approach is to provide a safety strap to retain the child in the cart seat. However, this approach does not address larger children who do not fit properly into the cart seat or parents that have more than one small child. U.S. Pat. No. 3,575,250 issued to Dykes and U.S. Pat. No. 4,771,840 issued to Keller disclose motorized attachments for shopping carts. However, the motorized units are intended for disabled individuals, not children. Additionally, the motorized units would be cost prohibitive for a broad base solution to the wide spread problem of child injuries relating to shopping carts. Additionally, both of the above patents disclose an articulated or pivotal joint between the carrier and the shopping cart which requires the passenger to steer the cart, a design totally impractical for a child passenger. U.S. Pat. No. 3,044,801 issued to Vicany discloses an occupant propelled shopping cart. However, the occupant portion is integrally formed with the cart and does not present a viable option for use with the millions of shopping carts in existence. Therefore, a child carrier accessory is needed for use with existing shopping and airport luggage carts that will allow more than one child, or larger children, to be carried safely without reducing the overall functionality of the cart. SUMMARY OF THE INVENTION The present invention relates to a child carrier accessory attachable to a conventional shopping or luggage cart which does not significantly reduce the overall functionality of the cart. The child carrier includes a platform supported by at least one swivel caster wheel, a seat area and a restraining device for holding the child to the seat. The carrier is rigidly attached to the rear portion of a cart so that the combined structure of the cart and the child carrier pivot as a single structure on the rear wheels of the cart. The preferred child carrier is constructed using a rotational molding process. Attaching the child carrier accessory to a cart shifts the center of gravity of the cart downward and toward the rear of the cart. Additionally, the seat area on the child carrier is preferably closer the ground than the child seat provided on these carts. Consequently, when a child is riding on the child carrier, the combined unit has a lower center of gravity than when a child is riding in the seat on a cart. In an alternate embodiment, the child carrier accessory may be attached to the rear of a cart in a cantilever fashion without the use of a swivel caster wheel to support the platform. This embodiment requires sufficient counterweight to insure stability of the cart. Conventional shopping or luggage carts generally include only a single child seat near the handle. This seat is only suitable for smaller children under approximately 30 pounds or 54 inches in heights. Consequently, parents with more than one child are tempted to allow the older child to ride in the basket portion of the cart or on the luggage rack. The present invention provides for carrying three children safely in the combined cart and child carrier accessory, while providing enhanced performance of the cart itself. The claimed child carrier accessory has the additional advantage of separating the child from the merchandise or luggage in the cart and providing additional carrying capacity. The child carrier includes a handle for maneuvering the combination shopping or luggage cart and child carrier. Since the handle on the child carrier extends behind the cart, the operator has additional leverage for maneuvering the combination cart and child carrier. When the cart is weighed down with merchandise or luggage, it is more easily maneuvered from the child carrier handle then from the handle on the cart. A center divider may be included in the seat area to provide separate seats for two children. Side supports are preferably located on either side of the seat area to provide additional lateral support for restraining the child in the carrier. A universal mounting bracket is provided with a variety of slotted mounted holes which allow the child carrier to be attached to any standard shopping or airport luggage cart. The mounting bracket preferably includes a reversible connector member bracket for connecting the child carrier to the cart. The reversible connector member bracket may be turned upside down to compensate for variation in the height of the cart frame relative the ground. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is perspective view of the preferred child carrier accessory attached to an exemplary shopping cart as viewed from the front of the child carrier; FIG. 2 is as perspective view of the preferred child carrier accessory attached to an exemplary shopping cart as viewed from the rear of the child carrier; FIG. 3 is a perspective view of the preferred mounting bracket for connecting the child carrier accessory to a shopping cart; FIG. 4 is bottom plan view of the child carrier accessory; FIG. 5 is an end view of the preferred mounting bracket for connecting the child carrier accessory to a cart; FIG. 6 is a top plan view of the child carrier accessory; FIG. 7 is a front elevation of the child carrier accessory; and FIG. 8 is perspective view of the preferred child carrier accessory attached to an exemplary luggage cart as viewed from the front of the child carrier. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1 and 2 are a perspective view of the preferred child carrier accessory 10 attached to an exemplary shopping cart 12. The child carrier accessory 10 has a platform 14 preferably supported by a pair of preferably swivel caster wheels 16, 18 (See FIG. 2), although it will be understood that other wheel structures are possible. A carrier body 20 located on the platform 14 contains a seat portion 22 with a center divider 24 to form left and right seat areas 26,28, respectively. (See also FIGS. 6 and 7). Curved back supports 30,32 having side support portions 34,36 are preferably integrally formed in the carrier body 20. A carrier handle 38 is provided on a back side 40 of the carrier body 20 for pushing the combination child carrier accessory 10 and shopping cart 12. The carrier handle 38 is preferably located at a comfortable height for pushing (i.e., approximately 38 inches above the ground). FIG. 8 is a perspective view of the preferred child carrier accessory 10 attached to an exemplary luggage cart 110 as viewed from the front of the child carrier 10. The cart 110 has a carrying location 112 for carrying luggage (not shown). The cart 110 has a child seat 60' near a cart handle 68' sufficient to carry one child. However, the luggage cart 110 tends to be lightweight so that it is extremely top-heavy if a child is placed in the seat 60' and the cart 110 is not loaded down with luggage. The carrier 10 is attached to the cart 110 using connector bars 70 and universal mounting bracket 72. The platform 14, mounting system 70, 72, and swivel caster wheels 16 (18 not shown) are all located below the child seat 60'. Since these components constitute a fair portion of the weight of the carrier 10, the combined carrier 10 and cart 110 has a lower center of gravity than the cart 110 alone. The center divider 24 and curved back supports 30 allow for two additional children to be carried in the child care accessory 10 using restraining mechanism 74. It will be understood that the remainder of the discussion is equally applicable to either a shopping cart or a luggage cart and that the present invention is not limited by the specific design of the shopping or luggage carts 12, 110. In an alternate embodiment, the child care accessory 10 may be attached to a cart in a cantilever fashion, without being supported by wheels. However, it will be understood that this embodiment requires a cart that can adequately counterbalance the weight of the carrier 10 and a child. Alternatively, a counter weight may be attached to the front portion of the cart. In the preferred embodiment, the child carrier accessory 10 is constructed using a rotational molding process. It will be understood that the child carrier may also be constructed by blow molding, thermal forming, vacuum forming or injection molding. The one-piece plastic child carrier of the preferred embodiment has been tested to hold dynamic weight to 650 lbs. Additionally, the preferred plastic construction is light weight (less than 40 lbs.) and cost effective to manufacture. However, it will be understood by those skilled in the art that a variety of manufacturing techniques are available for achieving the same result. In particular, the child carrier accessory may comprise a number of discrete parts which are assembled. Additionally, the child carrier accessory 10 may be made from a variety of materials including metal, wood, composites, and plastics. The carrier body 20 has a variety of surfaces, such as surfaces "S", suitable for displaying advertising material. The shopping cart 12 generally comprises a base frame 50 supported by a pair of front swivel caster wheels 52 and a pair of rear caster wheels 54. A carrying location defined by a basket portion 56 generally sits on top of the base frame 50. The basket portion 56 may be either metal or plastic. The basket portion 56 generally has a rear panel 58 which includes a child seat 60. In conventional shopping carts, the rear panel 58 includes a folding back support 62 hinged to the rear panel 58 and a fold down seat portion 64. The rear panel 58 also includes a pair of leg openings 66 which allow the child to sit facing the rear of the cart 12 proximate a cart handle 68. The seat portion 22 of the child carrier accessory 10 preferably has a restraining mechanism 74 for securing each child to the child carrier accessory 10. The preferred restraining mechanism 74 includes a waist strap 76 and a shoulder strap 78. Although not recommended by the manufacturer, the child can alternatively stand on the platform 14 while riding in the child carrier 10. A child standing on the platform can grip the cart handle 68 in front and is supported by the carrier body 20 from the rear. Because the platform 14 is relatively low to the ground, the child can get off and on the child carrier accessory 10 with minimal risk of injury. While not the ideal arrangement, experienced parents will recognize the advantage of this arrangement over attempting to restrain a child against his or her will. When the carts 12, 110 are empty, placing a child in the child seat 60, 60' significantly raises the center of gravity of the carts 12, 110. Since it is not uncommon for parents to place a child weighing 30 pounds or more in the child seat 60, 60', the risk of tipping over the cart 12, 100 is substantial. The seat portion 22 of the child carrier accessory 10 is preferably closer to the ground than the child seat 60, 60' in the carts 12, 110. Consequently, the combination child carrier accessory 10 and cart 12, 110 has a lower center of gravity than the carts along. When the carts 12, 100 is full of merchandise or luggage, they are difficult to maneuver because of the limited leverage provided by the cart handle 68, 68'. In particular, a loaded down cart has a high moment of inertia which is difficult to overcome from the cart handles 68, 68'. The combination child carrier accessory 10 and cart 12, 110 has a center of gravity close to the rear wheels of the carts 12, 110. The combined unit tends to pivot on the rear wheels, making it easy to maneuver even in close quarters. Also, since the carrier handle 38 on the child carrier accessory 10 is located behind the cart handle 68, 68' by a distance "d", the user has greater leverage for maneuvering the combination cart 12, 110 and child carrier accessory 10. The distance "d" is approximately 20 inches in the preferred embodiment. The child carrier accessory 10 is preferably attached to the rear of the base frame 50 by a pair of connector bars 70. Utilizing two connector bars 70 provides lateral support for maneuvering the combined unit. However, it will be understood by those skilled in the art that a variety of connector members are suitable for this purpose. For example, the connection may be made by a single bar or a plate member. A universal mounting bracket 72, as will be discussed below, allows the child carrier accessory 10 to be attached to any size shopping or luggage cart. FIGS. 3-7 illustrate the universal mounting bracket 72 engaged with the connector bars 70 of the child carrier accessory 10. A pair of upper mounting plates 80 are attached to the base frame 50 of the shopping cart 12 by a U-shaped clamp 82 (See FIG. 5) through slotted mounting plate holes 84 (See FIG. 4) using nuts 86. Washer plates 81 may optionally be included between the nuts 86 and the upper mounting plates 80. The slotted mounting plate holes 84 permit the U-shaped clamp 82 to be adjusted lateral to compensate for differences in the various base frames 50 in use. While the preferred embodiment illustrates a pair of upper mounting plates 80, it will be understood that an equivalent result may be accomplished with a single plate and a variety of other means. A U-shaped connector bar bracket 88 is attached to the upper mounting plates 80 at a plurality of connector bar bracket slots 90 (See also FIGS. 5 and 6). The connector bar bracket slots 90 similarly permit lateral adjustment of the location of the connector bar bracket 88 relative to the base frame 50. The connector bar bracket 88 is preferably symmetrical so that it can be turned upside down and attached to the tops of the upper mounting plates 80. In doing so, the universal mounting bracket 72 can accommodate shopping carts with a base frame that is low to the ground, while maintaining the connector bars 70 in a horizontal configuration. The connector bars 70 are attached to height adjustment slot 92 on side portions 94 of the connector bar bracket 88 by bolts 96 and nuts 98. (See FIG. 5). The height adjustment slots 92 also contribute to allowing the connector bars 70 to be maintained in a horizontal position when connected to a variety of shopping carts with base frames of different heights. Alternatively, the connector bar bracket 88 may be inverted 180 degrees and attached to the tops of the upper mounting plates 80 so that the height adjustment slots 92 are above the upper mounting plates 80. This alternate configuration allows for attaching the connector bars 70 horizontally to the base frame 50 of a shopping cart that rides low to the ground. The connector bars 70 preferably have a plurality of positioning holes 100 which permit adjustment of the distance between the platform 14 of the child carrier accessory 10 and the rear of the shopping cart 12. In the preferred embodiment, the child carrier accessory 10 adds only 20 inches to the overall length of the shopping cart 12. The various mounting slots 84, 90, 92 on the universal mounting bracket 72 and positioning holes 100 on the connector bars 70 allow for significant variations in the height and other dimensions of the base frame 50 while attaching the child carrier accessory 10 in the optimum configuration. It will be understood by those skilled in the art that a variety of mounting brackets are possible for attaching the child carrier accessory to a shopping cart. The configuration illustrated in FIGS. 3-7 is set forth by way of example only and in no way limits the scope of the invention. FIG. 4 is bottom plan view of the child carrier accessory 10 illustrating the location of the swivel caster wheels 16, 18 relative to the connector bars 70. In the preferred embodiment, the distance "w" between the wheels 16, 18 is slightly less than the distance between the rear wheels 54 of the shopping cart 12. This spacing enhances the pivoting of the combined unit 10, 12 on the rear wheels 54. However, it will be understood that in some circumstances, the distance "w" between the wheels 16, 18 may be greater than the distance between the wheels 54 on the shopping cart 12. FIG. 5 is an end view of the universal mounting bracket 72 for connecting the child carrier accessory 10 to a shopping cart 12. While the clamp 82 for engaging the base frame 50 is generally U-shaped, it will be understood that it can be any shape necessary to engage with the base frame 50 of the shopping cart 12. Likewise, while the connector bars 70 are square, it will be understood that they can be for example, round, rectangular or any other suitable shape. FIGS. 6 and 7 illustrate a top and front plan view, respectively, of the child carrier accessory 10. While FIGS. 6 and 7 illustrates the carrier body 20 having a center divider 24, it will be understood that the center divider 24 may be removed without departing from the scope of the present invention. It will be understood that these exemplary embodiments in no way limit the scope of the invention. Other modifications of the invention will be apparent to those skilled in the art in view of the foregoing description. These descriptions are intended to provide specific examples of embodiments which clearly disclose the present invention. Accordingly, the invention is not limited to the described embodiments or to the use of specific elements, dimensions, materials or configurations contained therein. All alternative modifications and variations of the present invention which fall within the spirit and broad scope of the appended claims are covered.
A child carrier accessory attachable to a shopping or luggage cart which does not significantly reduce the functionality of the cart.
Summarize the patent document, focusing on the invention's functionality and advantages.
[ "This is a continuation of application Ser.", "No. 08/250,550, filed May 27, 1994 now abandoned.", "FIELD OF THE INVENTION The present invention relates to child carriers attachable to a cart, and in particular, to a child carrier accessory attachable to an ordinary shopping or luggage cart which does not significantly reduce the functionality of the cart.", "BACKGROUND OF THE INVENTION Shopping carts found in retail establishments generally include a child seat that is part of the rear panel of the shopping cart basket.", "A back support panel is attached to the rear panel, usually on the inside of the basket, thereby reducing the carrying capacity of the shopping cart.", "A fold down seat portion traverses the back support panel and the rear panel to form the child set proximate the upper portion of the rear panel.", "Generally, the child seat is arranged so that the child's legs extend through openings in the back panel.", "Airport luggage carts have a similar child seat arrangement.", "However, luggage carts weigh less than a shopping cart and are therefore more prone to tip over.", "The child seats on shopping or luggage carts only have room for one child.", "Also, once a child reaches approximately 35 pounds, or is more than approximately 54"", "tall, the child seat on these carts starts to be too small and uncomfortable for the child.", "Additionally, children older than approximately 3 years find these seats confining and often attempt to climb out.", "Consequently, it is very common to see children riding in the basket portion of the shopping cart or standing on the front edge of the lower frame while gripping onto the basket portion, or standing on the luggage portion of a luggage cart.", "Allowing a child to ride in the basket portion of the shopping cart has proven to be extremely dangerous.", "The U.S. Consumer Product Safety Commission reported 12,000 hospital emergency room head injuries in 1988 along, to children under 5 years of age primarily due to children falling from shopping carts.", "Approximately one third of these head injuries were concussions, fractures or internal injuries.", "(See Consumer Product Safety Alert from the U.S. Consumer Product Safety Commission, March 1990, which is hereby incorporated by reference.) In 1992, the U.S. Consumer Product Safety Commission estimates that 22,920 children were treated in hospital emergency rooms for injuries related to shopping carts.", "While old style shopping carts were constructed of metal, newer carts are utilizing more plastic parts, including plastic basket portions.", "Consequently, the center of gravity of newer shopping carts is much lower than the old style metal carts.", "Since the child seat is generally on the upper portion of the rear panel of the basket portion, a larger child will significantly alter the center of gravity of the cart, especially when the cart is empty.", "The reported accidents also include injuries resulting from children tipping over the cart by rocking back and forth.", "There are presently millions of conventional shopping and luggage carts in use.", "A shopping cart costs anywhere from $70.00 to $120.00.", "An economically viable solution to child injuries needs to utilize the existing inventory of carts, without significantly reducing the overall functionality of the carts.", "For example, the solution can not dramatically change the dimensions of the cart.", "One approach is to provide a safety strap to retain the child in the cart seat.", "However, this approach does not address larger children who do not fit properly into the cart seat or parents that have more than one small child.", "U.S. Pat. No. 3,575,250 issued to Dykes and U.S. Pat. No. 4,771,840 issued to Keller disclose motorized attachments for shopping carts.", "However, the motorized units are intended for disabled individuals, not children.", "Additionally, the motorized units would be cost prohibitive for a broad base solution to the wide spread problem of child injuries relating to shopping carts.", "Additionally, both of the above patents disclose an articulated or pivotal joint between the carrier and the shopping cart which requires the passenger to steer the cart, a design totally impractical for a child passenger.", "U.S. Pat. No. 3,044,801 issued to Vicany discloses an occupant propelled shopping cart.", "However, the occupant portion is integrally formed with the cart and does not present a viable option for use with the millions of shopping carts in existence.", "Therefore, a child carrier accessory is needed for use with existing shopping and airport luggage carts that will allow more than one child, or larger children, to be carried safely without reducing the overall functionality of the cart.", "SUMMARY OF THE INVENTION The present invention relates to a child carrier accessory attachable to a conventional shopping or luggage cart which does not significantly reduce the overall functionality of the cart.", "The child carrier includes a platform supported by at least one swivel caster wheel, a seat area and a restraining device for holding the child to the seat.", "The carrier is rigidly attached to the rear portion of a cart so that the combined structure of the cart and the child carrier pivot as a single structure on the rear wheels of the cart.", "The preferred child carrier is constructed using a rotational molding process.", "Attaching the child carrier accessory to a cart shifts the center of gravity of the cart downward and toward the rear of the cart.", "Additionally, the seat area on the child carrier is preferably closer the ground than the child seat provided on these carts.", "Consequently, when a child is riding on the child carrier, the combined unit has a lower center of gravity than when a child is riding in the seat on a cart.", "In an alternate embodiment, the child carrier accessory may be attached to the rear of a cart in a cantilever fashion without the use of a swivel caster wheel to support the platform.", "This embodiment requires sufficient counterweight to insure stability of the cart.", "Conventional shopping or luggage carts generally include only a single child seat near the handle.", "This seat is only suitable for smaller children under approximately 30 pounds or 54 inches in heights.", "Consequently, parents with more than one child are tempted to allow the older child to ride in the basket portion of the cart or on the luggage rack.", "The present invention provides for carrying three children safely in the combined cart and child carrier accessory, while providing enhanced performance of the cart itself.", "The claimed child carrier accessory has the additional advantage of separating the child from the merchandise or luggage in the cart and providing additional carrying capacity.", "The child carrier includes a handle for maneuvering the combination shopping or luggage cart and child carrier.", "Since the handle on the child carrier extends behind the cart, the operator has additional leverage for maneuvering the combination cart and child carrier.", "When the cart is weighed down with merchandise or luggage, it is more easily maneuvered from the child carrier handle then from the handle on the cart.", "A center divider may be included in the seat area to provide separate seats for two children.", "Side supports are preferably located on either side of the seat area to provide additional lateral support for restraining the child in the carrier.", "A universal mounting bracket is provided with a variety of slotted mounted holes which allow the child carrier to be attached to any standard shopping or airport luggage cart.", "The mounting bracket preferably includes a reversible connector member bracket for connecting the child carrier to the cart.", "The reversible connector member bracket may be turned upside down to compensate for variation in the height of the cart frame relative the ground.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is perspective view of the preferred child carrier accessory attached to an exemplary shopping cart as viewed from the front of the child carrier;", "FIG. 2 is as perspective view of the preferred child carrier accessory attached to an exemplary shopping cart as viewed from the rear of the child carrier;", "FIG. 3 is a perspective view of the preferred mounting bracket for connecting the child carrier accessory to a shopping cart;", "FIG. 4 is bottom plan view of the child carrier accessory;", "FIG. 5 is an end view of the preferred mounting bracket for connecting the child carrier accessory to a cart;", "FIG. 6 is a top plan view of the child carrier accessory;", "FIG. 7 is a front elevation of the child carrier accessory;", "and FIG. 8 is perspective view of the preferred child carrier accessory attached to an exemplary luggage cart as viewed from the front of the child carrier.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1 and 2 are a perspective view of the preferred child carrier accessory 10 attached to an exemplary shopping cart 12.", "The child carrier accessory 10 has a platform 14 preferably supported by a pair of preferably swivel caster wheels 16, 18 (See FIG. 2), although it will be understood that other wheel structures are possible.", "A carrier body 20 located on the platform 14 contains a seat portion 22 with a center divider 24 to form left and right seat areas 26,28, respectively.", "(See also FIGS. 6 and 7).", "Curved back supports 30,32 having side support portions 34,36 are preferably integrally formed in the carrier body 20.", "A carrier handle 38 is provided on a back side 40 of the carrier body 20 for pushing the combination child carrier accessory 10 and shopping cart 12.", "The carrier handle 38 is preferably located at a comfortable height for pushing (i.e., approximately 38 inches above the ground).", "FIG. 8 is a perspective view of the preferred child carrier accessory 10 attached to an exemplary luggage cart 110 as viewed from the front of the child carrier 10.", "The cart 110 has a carrying location 112 for carrying luggage (not shown).", "The cart 110 has a child seat 60'", "near a cart handle 68'", "sufficient to carry one child.", "However, the luggage cart 110 tends to be lightweight so that it is extremely top-heavy if a child is placed in the seat 60'", "and the cart 110 is not loaded down with luggage.", "The carrier 10 is attached to the cart 110 using connector bars 70 and universal mounting bracket 72.", "The platform 14, mounting system 70, 72, and swivel caster wheels 16 (18 not shown) are all located below the child seat 60'.", "Since these components constitute a fair portion of the weight of the carrier 10, the combined carrier 10 and cart 110 has a lower center of gravity than the cart 110 alone.", "The center divider 24 and curved back supports 30 allow for two additional children to be carried in the child care accessory 10 using restraining mechanism 74.", "It will be understood that the remainder of the discussion is equally applicable to either a shopping cart or a luggage cart and that the present invention is not limited by the specific design of the shopping or luggage carts 12, 110.", "In an alternate embodiment, the child care accessory 10 may be attached to a cart in a cantilever fashion, without being supported by wheels.", "However, it will be understood that this embodiment requires a cart that can adequately counterbalance the weight of the carrier 10 and a child.", "Alternatively, a counter weight may be attached to the front portion of the cart.", "In the preferred embodiment, the child carrier accessory 10 is constructed using a rotational molding process.", "It will be understood that the child carrier may also be constructed by blow molding, thermal forming, vacuum forming or injection molding.", "The one-piece plastic child carrier of the preferred embodiment has been tested to hold dynamic weight to 650 lbs.", "Additionally, the preferred plastic construction is light weight (less than 40 lbs.) and cost effective to manufacture.", "However, it will be understood by those skilled in the art that a variety of manufacturing techniques are available for achieving the same result.", "In particular, the child carrier accessory may comprise a number of discrete parts which are assembled.", "Additionally, the child carrier accessory 10 may be made from a variety of materials including metal, wood, composites, and plastics.", "The carrier body 20 has a variety of surfaces, such as surfaces "S", suitable for displaying advertising material.", "The shopping cart 12 generally comprises a base frame 50 supported by a pair of front swivel caster wheels 52 and a pair of rear caster wheels 54.", "A carrying location defined by a basket portion 56 generally sits on top of the base frame 50.", "The basket portion 56 may be either metal or plastic.", "The basket portion 56 generally has a rear panel 58 which includes a child seat 60.", "In conventional shopping carts, the rear panel 58 includes a folding back support 62 hinged to the rear panel 58 and a fold down seat portion 64.", "The rear panel 58 also includes a pair of leg openings 66 which allow the child to sit facing the rear of the cart 12 proximate a cart handle 68.", "The seat portion 22 of the child carrier accessory 10 preferably has a restraining mechanism 74 for securing each child to the child carrier accessory 10.", "The preferred restraining mechanism 74 includes a waist strap 76 and a shoulder strap 78.", "Although not recommended by the manufacturer, the child can alternatively stand on the platform 14 while riding in the child carrier 10.", "A child standing on the platform can grip the cart handle 68 in front and is supported by the carrier body 20 from the rear.", "Because the platform 14 is relatively low to the ground, the child can get off and on the child carrier accessory 10 with minimal risk of injury.", "While not the ideal arrangement, experienced parents will recognize the advantage of this arrangement over attempting to restrain a child against his or her will.", "When the carts 12, 110 are empty, placing a child in the child seat 60, 60'", "significantly raises the center of gravity of the carts 12, 110.", "Since it is not uncommon for parents to place a child weighing 30 pounds or more in the child seat 60, 60', the risk of tipping over the cart 12, 100 is substantial.", "The seat portion 22 of the child carrier accessory 10 is preferably closer to the ground than the child seat 60, 60'", "in the carts 12, 110.", "Consequently, the combination child carrier accessory 10 and cart 12, 110 has a lower center of gravity than the carts along.", "When the carts 12, 100 is full of merchandise or luggage, they are difficult to maneuver because of the limited leverage provided by the cart handle 68, 68'.", "In particular, a loaded down cart has a high moment of inertia which is difficult to overcome from the cart handles 68, 68'.", "The combination child carrier accessory 10 and cart 12, 110 has a center of gravity close to the rear wheels of the carts 12, 110.", "The combined unit tends to pivot on the rear wheels, making it easy to maneuver even in close quarters.", "Also, since the carrier handle 38 on the child carrier accessory 10 is located behind the cart handle 68, 68'", "by a distance "d", the user has greater leverage for maneuvering the combination cart 12, 110 and child carrier accessory 10.", "The distance "d"", "is approximately 20 inches in the preferred embodiment.", "The child carrier accessory 10 is preferably attached to the rear of the base frame 50 by a pair of connector bars 70.", "Utilizing two connector bars 70 provides lateral support for maneuvering the combined unit.", "However, it will be understood by those skilled in the art that a variety of connector members are suitable for this purpose.", "For example, the connection may be made by a single bar or a plate member.", "A universal mounting bracket 72, as will be discussed below, allows the child carrier accessory 10 to be attached to any size shopping or luggage cart.", "FIGS. 3-7 illustrate the universal mounting bracket 72 engaged with the connector bars 70 of the child carrier accessory 10.", "A pair of upper mounting plates 80 are attached to the base frame 50 of the shopping cart 12 by a U-shaped clamp 82 (See FIG. 5) through slotted mounting plate holes 84 (See FIG. 4) using nuts 86.", "Washer plates 81 may optionally be included between the nuts 86 and the upper mounting plates 80.", "The slotted mounting plate holes 84 permit the U-shaped clamp 82 to be adjusted lateral to compensate for differences in the various base frames 50 in use.", "While the preferred embodiment illustrates a pair of upper mounting plates 80, it will be understood that an equivalent result may be accomplished with a single plate and a variety of other means.", "A U-shaped connector bar bracket 88 is attached to the upper mounting plates 80 at a plurality of connector bar bracket slots 90 (See also FIGS. 5 and 6).", "The connector bar bracket slots 90 similarly permit lateral adjustment of the location of the connector bar bracket 88 relative to the base frame 50.", "The connector bar bracket 88 is preferably symmetrical so that it can be turned upside down and attached to the tops of the upper mounting plates 80.", "In doing so, the universal mounting bracket 72 can accommodate shopping carts with a base frame that is low to the ground, while maintaining the connector bars 70 in a horizontal configuration.", "The connector bars 70 are attached to height adjustment slot 92 on side portions 94 of the connector bar bracket 88 by bolts 96 and nuts 98.", "(See FIG. 5).", "The height adjustment slots 92 also contribute to allowing the connector bars 70 to be maintained in a horizontal position when connected to a variety of shopping carts with base frames of different heights.", "Alternatively, the connector bar bracket 88 may be inverted 180 degrees and attached to the tops of the upper mounting plates 80 so that the height adjustment slots 92 are above the upper mounting plates 80.", "This alternate configuration allows for attaching the connector bars 70 horizontally to the base frame 50 of a shopping cart that rides low to the ground.", "The connector bars 70 preferably have a plurality of positioning holes 100 which permit adjustment of the distance between the platform 14 of the child carrier accessory 10 and the rear of the shopping cart 12.", "In the preferred embodiment, the child carrier accessory 10 adds only 20 inches to the overall length of the shopping cart 12.", "The various mounting slots 84, 90, 92 on the universal mounting bracket 72 and positioning holes 100 on the connector bars 70 allow for significant variations in the height and other dimensions of the base frame 50 while attaching the child carrier accessory 10 in the optimum configuration.", "It will be understood by those skilled in the art that a variety of mounting brackets are possible for attaching the child carrier accessory to a shopping cart.", "The configuration illustrated in FIGS. 3-7 is set forth by way of example only and in no way limits the scope of the invention.", "FIG. 4 is bottom plan view of the child carrier accessory 10 illustrating the location of the swivel caster wheels 16, 18 relative to the connector bars 70.", "In the preferred embodiment, the distance "w"", "between the wheels 16, 18 is slightly less than the distance between the rear wheels 54 of the shopping cart 12.", "This spacing enhances the pivoting of the combined unit 10, 12 on the rear wheels 54.", "However, it will be understood that in some circumstances, the distance "w"", "between the wheels 16, 18 may be greater than the distance between the wheels 54 on the shopping cart 12.", "FIG. 5 is an end view of the universal mounting bracket 72 for connecting the child carrier accessory 10 to a shopping cart 12.", "While the clamp 82 for engaging the base frame 50 is generally U-shaped, it will be understood that it can be any shape necessary to engage with the base frame 50 of the shopping cart 12.", "Likewise, while the connector bars 70 are square, it will be understood that they can be for example, round, rectangular or any other suitable shape.", "FIGS. 6 and 7 illustrate a top and front plan view, respectively, of the child carrier accessory 10.", "While FIGS. 6 and 7 illustrates the carrier body 20 having a center divider 24, it will be understood that the center divider 24 may be removed without departing from the scope of the present invention.", "It will be understood that these exemplary embodiments in no way limit the scope of the invention.", "Other modifications of the invention will be apparent to those skilled in the art in view of the foregoing description.", "These descriptions are intended to provide specific examples of embodiments which clearly disclose the present invention.", "Accordingly, the invention is not limited to the described embodiments or to the use of specific elements, dimensions, materials or configurations contained therein.", "All alternative modifications and variations of the present invention which fall within the spirit and broad scope of the appended claims are covered." ]
TECHNICAL FIELD This invention relates to electronic device connectors in general, and specifically to printed circuit board (PCB) edge connectors meeting the Peripheral Component Interconnect (“PCI”) Express technical standard for electronic and computer devices. More particularly, this invention relates to a PCI Express connection device that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between such devices. Specifically, a PCI Express connector is disclosed that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension(s) of the adapter. BACKGROUND Most electronic and computer circuitry is now implemented with active and passive devices coupled together through use of a printed circuit board (PCB). This is true whether the circuitry is primarily analog in nature, digital in nature, or a hybrid of the two. In its simplest form, a PCB is a relatively thin sheet of dielectric (i.e. electrically non-conductive) material such as a resin-filled fiberglass. Metal lines or “traces” are typically formed on one or more surfaces of the PCB to provide electrical connection(s) between components of the various electronic circuits located on the PCB. Furthermore, PCBs can be “multi-layered” where multiple dielectric layers are located between conductive layers to form circuit, ground and/or power planes. With multi-layer boards, it is common to provide electrical connections between various layers by the formation of “vias” (or conductive plugs) between layers, or by use of “through-holes” in which conductors can be threaded. Commonly, the circuit(s) on a PCB can be connected to other devices. These may be input/output devices, other electronic and/or computer circuits located on other PCBs, transmission lines, etc. While such devices can be connected directly to a PCB (such as by being soldered to some of its traces or bonding pads), the connection to external devices or circuits is most commonly made through a removable connector assembly. Many different types of electrical connectors have been developed through the years for this purpose, and they have been designed according to several industry technical standards in order to create uniformity in their manufacture, implementation and use. One of the most widely adopted of such standards currently used in desktop and server computing is the Peripheral Component Interconnect (or “PCI”) standard. The original IBM® personal computer (PC) architecture had a series of related hardware communication interface (or “bus”) designs rooted in the original Industry Standard Architecture (ISA) specification that led to development and adoption of the PCI standard. The original ISA specification allowed for a bus having a size (or “width”) of 16 binary information-containing digits (or “bits” in forming a binary “word”) to carry electrical signals transmitted simultaneously (or “in parallel”) for use in executing computer device addressing, data processing and control functions. However, the ISA bus architecture has a number of drawbacks, including lack of speed, being difficult to configure, and an incomplete set of standard specifications, all leading to a lack of compatibility for use with some applications. For this reason, several other proprietary bus architectures have been developed that are considered to be technically superior to ISA; including a 32-bit variant of ISA (EISA); the Micro Channel Architecture (MCA) bus developed by IBM®; NuBus developed by Apple®; SBus developed by Sun®; Zorro II (16-bit) and Zorro III (32-bit) used by Amiga; the VESA Local bus developed by the Video Electronics Standards Association; and the PCI standard which was developed by Intel®. The PCI specification was first proposed as a standard in 1991, and it was originally designed for interconnecting circuits and devices on a PCB main circuit board (or “motherboard”), but its use has since been expanded to removable circuit cards and other computer and electronic devices. The PCI bus architecture possesses a number of advantages over other bus architectures; such as providing direct access to computer system memory without central processing unit (“CPU”) intervention; allowing for interconnection of multiple electronic and/or computer devices through a single bus (including the use of “bridges” that allow a single interconnection to be used for a connection to even more devices) and automatic configuration (or “auto-configuration”) capability. Because of these advantages (among others) along with its speed and relatively inexpensive implementation, the PCI bus architecture standard is now used in virtually every type of computer and electronic system for providing communication between hardware devices. PCI Express is the latest development in the PCI standard to support use of connectors, expansion adapters and peripheral devices in PCs, workstations, servers, and other types of computer and electronic hardware. The bus technology implemented by the PCI Express standard can be used to provide microchip, printed circuit board (PCB), and adapter connectivity allowing communication between hardware devices in various types of computer and electronic systems. This is accomplished by implementation of a “serial” interface that allows for sequential transmission of data using point-to-point interconnections between devices, with directly wired interfaces between these connection points that usually consists of a connector/adapter combination. The PCI-X and PCI Express standards remain compatible at the software level even though the underlying hardware technology is different between the two standards. This permits PCI-X based operating systems, device drivers and BIOS systems to support PCI Express based hardware devices without any significant changes. The PCI Express standard is not limited to use with connectors for adapters. Due to its high speed and scalable bus widths, it can be used as a high speed interface to connect many different devices incorporating different hardware designs, such as USB 2, Infiniband, Gigabit Ethernet, and others. Devices can currently be operated under the PCI Express standard at a speed which is over double the bandwidth capability of current PCI-X devices. Future system operating frequency increases and improvements in conductor materials will cause corresponding increases in the total bandwidth that the PCI Express standard is capable of supporting. SUMMARY OF THE INVENTION A method, apparatus and system are disclosed for a connection device that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between electronic and/or computer devices. Specifically, a Peripheral Component Interconnect (“PCI”) Express connector is disclosed that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself. The PCI Express specification allows a device having a larger (or “wider”) bus capacity to be electrically connected to a smaller (or “narrower”) bus. However, a mechanical limitation exists with each type of PCI Express connector currently used to connect the bus to the device adapter, since the physical dimension(s) of the connector do not support its use with an adapter having a wider bus interface than that of the connector itself. All current solutions to this problem use a PCI Express connector having a bus width at least as large as that of the installed adapter while wiring only a portion of the connector to the system bus for use with the adapter. The present invention solves these problems by providing a new type of PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension(s) of the adapter. The “notch” concept of this invention eliminates the disadvantages experienced with current solutions while also allowing the connector to be compliant with the PCI Express specification, and it can be used to manufacture a variety of different PCI Express connectors as well as connectors for other expansion busses. It is therefore an object of the present invention to overcome the disadvantages of the prior art by providing a method, apparatus and system using a connection device that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between electronic and/or computer devices. It is another object of the present invention to overcome the disadvantages of the prior art by providing a connector that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between electronic and/or computer devices meeting the Peripheral Component Interconnect (“PCI”) Express technical standard. It is another object of the present invention to overcome the disadvantages of the prior art by providing a PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself. It is another object of the present invention to overcome the disadvantages of the prior art by providing a PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension(s) of the adapter. The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DETAILED DRAWINGS FIG. 1 is a schematic diagram illustrating a PCI Express serial link electrical connection. FIG. 2 illustrates a comparison of mechanical slot sizes for various PCI and PCI Express connector/adapter configurations. FIGS. 3 & 4 are perspective views illustrating a plug-in card edge connector system of the prior art. FIGS. 5A-5C are perspective views illustrating a “notched” PCI Express connector of the present invention. FIG. 6 is a perspective view illustrating a PCI Express adapter installed in a “notched” PCI Express connector of the present invention. FIGS. 7A & 7B are perspective views illustrating “outriggers” added near the end(s) of the “notched” PCI Express connector of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 3 & 4 illustrate a prior art printed circuit board (PCB) edge connection system that can be utilized under the PCI standard, as shown and described in U.S. Pat. No. 6,814,583 which is incorporated by reference herein. These connectors can be used to couple physically separated electronic devices, and although the connectors are shown to be attached to PCBs in FIGS. 3 & 4 , either connector could instead be coupled to a cable or to an individual circuit card. As shown in FIG. 3 , a first PCB or “plug-in board” 44 includes a male edge connector 46 , which can be implemented as a portion of the PCB with traces 48 that electrically connect with contacts 70 of a female edge connector 56 . In this particular example, the male edge connector 46 has a first portion 50 and a second portion 52 separated by a slot 54 . (There are also unslotted variants of edge connectors in the prior art.) The female edge connector 56 is provided with a pair of slots 66 and 68 including a number of contacts 70 which couple to the pins 62 . By extending its pins 62 through holes 64 , the female edge connector 56 can be electrically coupled to a PCB 58 having traces on its bottom surface 60 (not shown) although traces can also be located on a top surface 59 of the PCB. In operation, first and second portions 50 & 52 of male edge connector 46 are respectively inserted into slots 66 & 68 of female edge connector 56 , causing the traces 48 of plug-in board 44 to come into electrical contact with the traces of PCB 58 (not shown) through contacts 70 and pins 62 . FIG. 4 shows a prior art edge connector system 100 that includes a PCB motherboard 102 and one or more plug-in circuit cards 104 a , 104 b and/or 104 c . Each of the circuit cards includes a male edge connector portion 106 a , 106 b and/or 106 c , respectively, which can be a physical extension of the circuit card. Male edge connectors 106 a , 106 b and 106 c are adapted to engage the slots 108 a , 108 b and 108 c of female edge connectors 110 a , 110 b and 110 c , respectively. As a result, electronic circuitry on circuit cards 104 a - 104 c is electrically connected to circuitry on motherboard 102 when male edge connectors 106 a - 106 c are engaged with female edge connectors 110 a - 110 c. The connectors illustrated in FIGS. 3 & 4 have several advantages. They are mechanically guided and secured into place, which aids in retention of the electrical contact they make with each other. They are also well-shielded by their shells, which reduces electromagnetic radiation interference (EMI). Both types of connectors can vary in configuration and can assume a split-connector design as described with reference to FIG. 3 above. The edge connector technology illustrated in FIGS. 3 & 4 has certain advantages over other prior art systems, including the elimination of a separate male connector that reduces cost and brings the ground planes of the two PCBs closer together, which can be advantageous in high frequency applications. However, these prior art edge connector designs are intended for use with devices that implement a shared, parallel bus architecture for simultaneous signal processing. As explained above, the PCI Express standard implements a serial interface that allows for point-to-point interconnections between devices using directly wired interfaces between these connection points, requiring a different type of connector to satisfy this standard. As shown in FIG. 1 , a single PCI Express serial link is a dual-simplex connection using two pairs of wires (or “lanes”), one pair for transmitting data (Tx) and one pair for receiving data (Rx), that can each transfer one bit per cycle between connected devices A and B at a current speed of 2.5 gigabits per second (Gbps). A PCI Express link may be comprised of multiple lanes. In such configurations, the connection is labeled as ×1, ×2, ×4, ×8, ×16 or ×32 (or larger), etc., where the “x number” is effectively the number of lanes used in the link. Thus, a PCI Express ×1 configuration requires four (4) wires to connect the single-lane link, whereas an ×16 implementation requires sixteen (16) times that amount (or 64 wires) to complete the sixteen-lane link. This results in differently sized mechanical connections (or “slots”) for each different PCI Express link configuration. FIG. 2 shows a comparison of the slot sizes for current 32-bit PCI 2.0, PCI Express ×1 and PCI Express ×16 connector/adapter configurations, respectively. It is clear from this figure that a PCI Express adapter can be installed into a slot designed for a larger connection but a not smaller one. For example, a PCI Express ×16 adapter will not physically fit into a PCI ×1 connector slot, whereas a PCI Express ×1 adapter can be installed into a PCI ×16 connector slot. This compatibility is shown in the table below. x1 slot x4 slot x8 slot x16 slot X1 card Supported Supported Supported Supported X4 card No Supported Supported Supported X8 card No No Supported Supported X16 card No No No Supported As explained above, the PCI Express specification allows a device having a larger (or “wider”) bus capacity to be electrically connected to a smaller (or “narrower”) bus, such as for example by connecting a PCI Express ×16 device (having a 16-bit “word”-sized bus architecture) to a PCI Express ×8 (single-byte), ×4 (half-byte), or ×1 (single bit) bus through an adapter. However, as illustrated with reference to FIG. 2 , a mechanical limitation exists with each type of PCI Express connector currently used to connect the bus to the device adapter, since the physical dimension(s) of the connector do not support its use with an adapter having a wider bus interface than that of the connector itself. As a result, a PCI Express ×16 adapter cannot currently be installed in a PCI Express ×8, ×4, or ×1 connector slot due to this mechanical limitation. All current solutions to this problem use a PCI Express connector having a bus width at least as large as that of the installed adapter while wiring only a portion of the connector to the system bus for use with the adapter. For example, by wiring only eight (8) of its connections to the system integrated circuit (IC) chipset on the PCB, a PCI Express ×16 connector may be used to connect an 8-bit (single byte-sized) system bus with a PCI Express ×8 or ×16 adapter by installing the adapter into the connector slot. However, this solution requires use of a larger, more expensive PCI Express connector taking up a greater amount of space than is necessary for the electrical connection being made, and it results in unused connections. The present invention solves these problems by providing a new type of PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension (s) of the adapter. As shown in FIGS. 5A-5C , a standard PCI Express connector 10 is modified by adding an opening (or “notch”) 20 to at least one end of the connector slot 15 (such as the one closest to the front of the system). The notch 20 allows PCI Express adapters 25 (i.e. “expansion cards”) that are larger in dimension than the connector slot 15 to be installed (or “plugged”) into the connector 10 via the slot, as shown in the example of FIG. 6 where a PCI Express ×16 adapter is installed in a PCI Express ×8 connector slot. As shown in FIGS. 5C & 7B , the notch can extend into the central region of the connector where the metal bus connection pins reside (as well as toward the bottom of the connector) to allow a PCI Express adapter card that is physically larger than the connector to fully seat into the connector as shown in FIG. 6 . As shown in FIGS. 7A & 7B , “outrigger” support(s) 30 (made of a material such as plastic) can be added near the end(s) of the PCI Express connector 10 where a notch 20 is included to prevent the connector walls from excessively flexing outward when an adapter 25 is installed, thereby ensuring adequate pressure to complete an electrical connection between the pins inside the connector and the fingers on the expansion card. The “outriggers” on each side of the connector can be staggered (as shown in FIG. 7A ) to allow multiple “notched” PCI Express connectors to be placed next to each other without creating mechanical interference problems. Even though a PCI Express ×8 connector is illustrated in the example described herein, the “notch” technique can be applied to a PCI Express connector of any size, or to any other expansion connector using an architecture that allows for different bus widths. The “notched” PCI Express connector of this invention thus overcomes the disadvantages of the prior art by eliminating the problems experienced with current PCI Express connector/adapter configurations, while also allowing the connector to be compliant with the PCI Express specification, and it can be used to manufacture a variety of different PCI Express connectors as well as connectors for other expansion busses. While certain preferred features of the invention have been shown by way of illustration, many modifications and changes can be made that fall within the true spirit of the invention as embodied in the following claims, which are to be interpreted as broadly as the law permits to cover the full scope of the invention, including all equivalents thereto.
A method, apparatus and system are disclosed for a Peripheral Component Interconnect (“PCI”) Express connection device that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between electronic and/or computer devices. Specifically, a PCI Express connector is disclosed that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension(s) of the adapter.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "TECHNICAL FIELD This invention relates to electronic device connectors in general, and specifically to printed circuit board (PCB) edge connectors meeting the Peripheral Component Interconnect (“PCI”) Express technical standard for electronic and computer devices.", "More particularly, this invention relates to a PCI Express connection device that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between such devices.", "Specifically, a PCI Express connector is disclosed that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension(s) of the adapter.", "BACKGROUND Most electronic and computer circuitry is now implemented with active and passive devices coupled together through use of a printed circuit board (PCB).", "This is true whether the circuitry is primarily analog in nature, digital in nature, or a hybrid of the two.", "In its simplest form, a PCB is a relatively thin sheet of dielectric (i.e. electrically non-conductive) material such as a resin-filled fiberglass.", "Metal lines or “traces”", "are typically formed on one or more surfaces of the PCB to provide electrical connection(s) between components of the various electronic circuits located on the PCB.", "Furthermore, PCBs can be “multi-layered”", "where multiple dielectric layers are located between conductive layers to form circuit, ground and/or power planes.", "With multi-layer boards, it is common to provide electrical connections between various layers by the formation of “vias”", "(or conductive plugs) between layers, or by use of “through-holes”", "in which conductors can be threaded.", "Commonly, the circuit(s) on a PCB can be connected to other devices.", "These may be input/output devices, other electronic and/or computer circuits located on other PCBs, transmission lines, etc.", "While such devices can be connected directly to a PCB (such as by being soldered to some of its traces or bonding pads), the connection to external devices or circuits is most commonly made through a removable connector assembly.", "Many different types of electrical connectors have been developed through the years for this purpose, and they have been designed according to several industry technical standards in order to create uniformity in their manufacture, implementation and use.", "One of the most widely adopted of such standards currently used in desktop and server computing is the Peripheral Component Interconnect (or “PCI”) standard.", "The original IBM® personal computer (PC) architecture had a series of related hardware communication interface (or “bus”) designs rooted in the original Industry Standard Architecture (ISA) specification that led to development and adoption of the PCI standard.", "The original ISA specification allowed for a bus having a size (or “width”) of 16 binary information-containing digits (or “bits”", "in forming a binary “word”) to carry electrical signals transmitted simultaneously (or “in parallel”) for use in executing computer device addressing, data processing and control functions.", "However, the ISA bus architecture has a number of drawbacks, including lack of speed, being difficult to configure, and an incomplete set of standard specifications, all leading to a lack of compatibility for use with some applications.", "For this reason, several other proprietary bus architectures have been developed that are considered to be technically superior to ISA;", "including a 32-bit variant of ISA (EISA);", "the Micro Channel Architecture (MCA) bus developed by IBM®;", "NuBus developed by Apple®;", "SBus developed by Sun®;", "Zorro II (16-bit) and Zorro III (32-bit) used by Amiga;", "the VESA Local bus developed by the Video Electronics Standards Association;", "and the PCI standard which was developed by Intel®.", "The PCI specification was first proposed as a standard in 1991, and it was originally designed for interconnecting circuits and devices on a PCB main circuit board (or “motherboard”), but its use has since been expanded to removable circuit cards and other computer and electronic devices.", "The PCI bus architecture possesses a number of advantages over other bus architectures;", "such as providing direct access to computer system memory without central processing unit (“CPU”) intervention;", "allowing for interconnection of multiple electronic and/or computer devices through a single bus (including the use of “bridges”", "that allow a single interconnection to be used for a connection to even more devices) and automatic configuration (or “auto-configuration”) capability.", "Because of these advantages (among others) along with its speed and relatively inexpensive implementation, the PCI bus architecture standard is now used in virtually every type of computer and electronic system for providing communication between hardware devices.", "PCI Express is the latest development in the PCI standard to support use of connectors, expansion adapters and peripheral devices in PCs, workstations, servers, and other types of computer and electronic hardware.", "The bus technology implemented by the PCI Express standard can be used to provide microchip, printed circuit board (PCB), and adapter connectivity allowing communication between hardware devices in various types of computer and electronic systems.", "This is accomplished by implementation of a “serial”", "interface that allows for sequential transmission of data using point-to-point interconnections between devices, with directly wired interfaces between these connection points that usually consists of a connector/adapter combination.", "The PCI-X and PCI Express standards remain compatible at the software level even though the underlying hardware technology is different between the two standards.", "This permits PCI-X based operating systems, device drivers and BIOS systems to support PCI Express based hardware devices without any significant changes.", "The PCI Express standard is not limited to use with connectors for adapters.", "Due to its high speed and scalable bus widths, it can be used as a high speed interface to connect many different devices incorporating different hardware designs, such as USB 2, Infiniband, Gigabit Ethernet, and others.", "Devices can currently be operated under the PCI Express standard at a speed which is over double the bandwidth capability of current PCI-X devices.", "Future system operating frequency increases and improvements in conductor materials will cause corresponding increases in the total bandwidth that the PCI Express standard is capable of supporting.", "SUMMARY OF THE INVENTION A method, apparatus and system are disclosed for a connection device that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between electronic and/or computer devices.", "Specifically, a Peripheral Component Interconnect (“PCI”) Express connector is disclosed that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself.", "The PCI Express specification allows a device having a larger (or “wider”) bus capacity to be electrically connected to a smaller (or “narrower”) bus.", "However, a mechanical limitation exists with each type of PCI Express connector currently used to connect the bus to the device adapter, since the physical dimension(s) of the connector do not support its use with an adapter having a wider bus interface than that of the connector itself.", "All current solutions to this problem use a PCI Express connector having a bus width at least as large as that of the installed adapter while wiring only a portion of the connector to the system bus for use with the adapter.", "The present invention solves these problems by providing a new type of PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension(s) of the adapter.", "The “notch”", "concept of this invention eliminates the disadvantages experienced with current solutions while also allowing the connector to be compliant with the PCI Express specification, and it can be used to manufacture a variety of different PCI Express connectors as well as connectors for other expansion busses.", "It is therefore an object of the present invention to overcome the disadvantages of the prior art by providing a method, apparatus and system using a connection device that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between electronic and/or computer devices.", "It is another object of the present invention to overcome the disadvantages of the prior art by providing a connector that supports use of device bus widths different than the size of the connector in communication of data processing, addressing and/or control signals between electronic and/or computer devices meeting the Peripheral Component Interconnect (“PCI”) Express technical standard.", "It is another object of the present invention to overcome the disadvantages of the prior art by providing a PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself.", "It is another object of the present invention to overcome the disadvantages of the prior art by providing a PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension(s) of the adapter.", "The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification.", "The invention, however, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings.", "BRIEF DESCRIPTION OF THE DETAILED DRAWINGS FIG. 1 is a schematic diagram illustrating a PCI Express serial link electrical connection.", "FIG. 2 illustrates a comparison of mechanical slot sizes for various PCI and PCI Express connector/adapter configurations.", "FIGS. 3 &", "4 are perspective views illustrating a plug-in card edge connector system of the prior art.", "FIGS. 5A-5C are perspective views illustrating a “notched”", "PCI Express connector of the present invention.", "FIG. 6 is a perspective view illustrating a PCI Express adapter installed in a “notched”", "PCI Express connector of the present invention.", "FIGS. 7A &", "7B are perspective views illustrating “outriggers”", "added near the end(s) of the “notched”", "PCI Express connector of the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 3 &", "4 illustrate a prior art printed circuit board (PCB) edge connection system that can be utilized under the PCI standard, as shown and described in U.S. Pat. No. 6,814,583 which is incorporated by reference herein.", "These connectors can be used to couple physically separated electronic devices, and although the connectors are shown to be attached to PCBs in FIGS. 3 &", "4 , either connector could instead be coupled to a cable or to an individual circuit card.", "As shown in FIG. 3 , a first PCB or “plug-in board”", "44 includes a male edge connector 46 , which can be implemented as a portion of the PCB with traces 48 that electrically connect with contacts 70 of a female edge connector 56 .", "In this particular example, the male edge connector 46 has a first portion 50 and a second portion 52 separated by a slot 54 .", "(There are also unslotted variants of edge connectors in the prior art.) The female edge connector 56 is provided with a pair of slots 66 and 68 including a number of contacts 70 which couple to the pins 62 .", "By extending its pins 62 through holes 64 , the female edge connector 56 can be electrically coupled to a PCB 58 having traces on its bottom surface 60 (not shown) although traces can also be located on a top surface 59 of the PCB.", "In operation, first and second portions 50 &", "52 of male edge connector 46 are respectively inserted into slots 66 &", "68 of female edge connector 56 , causing the traces 48 of plug-in board 44 to come into electrical contact with the traces of PCB 58 (not shown) through contacts 70 and pins 62 .", "FIG. 4 shows a prior art edge connector system 100 that includes a PCB motherboard 102 and one or more plug-in circuit cards 104 a , 104 b and/or 104 c .", "Each of the circuit cards includes a male edge connector portion 106 a , 106 b and/or 106 c , respectively, which can be a physical extension of the circuit card.", "Male edge connectors 106 a , 106 b and 106 c are adapted to engage the slots 108 a , 108 b and 108 c of female edge connectors 110 a , 110 b and 110 c , respectively.", "As a result, electronic circuitry on circuit cards 104 a - 104 c is electrically connected to circuitry on motherboard 102 when male edge connectors 106 a - 106 c are engaged with female edge connectors 110 a - 110 c. The connectors illustrated in FIGS. 3 &", "4 have several advantages.", "They are mechanically guided and secured into place, which aids in retention of the electrical contact they make with each other.", "They are also well-shielded by their shells, which reduces electromagnetic radiation interference (EMI).", "Both types of connectors can vary in configuration and can assume a split-connector design as described with reference to FIG. 3 above.", "The edge connector technology illustrated in FIGS. 3 &", "4 has certain advantages over other prior art systems, including the elimination of a separate male connector that reduces cost and brings the ground planes of the two PCBs closer together, which can be advantageous in high frequency applications.", "However, these prior art edge connector designs are intended for use with devices that implement a shared, parallel bus architecture for simultaneous signal processing.", "As explained above, the PCI Express standard implements a serial interface that allows for point-to-point interconnections between devices using directly wired interfaces between these connection points, requiring a different type of connector to satisfy this standard.", "As shown in FIG. 1 , a single PCI Express serial link is a dual-simplex connection using two pairs of wires (or “lanes”), one pair for transmitting data (Tx) and one pair for receiving data (Rx), that can each transfer one bit per cycle between connected devices A and B at a current speed of 2.5 gigabits per second (Gbps).", "A PCI Express link may be comprised of multiple lanes.", "In such configurations, the connection is labeled as ×1, ×2, ×4, ×8, ×16 or ×32 (or larger), etc.", ", where the “x number”", "is effectively the number of lanes used in the link.", "Thus, a PCI Express ×1 configuration requires four (4) wires to connect the single-lane link, whereas an ×16 implementation requires sixteen (16) times that amount (or 64 wires) to complete the sixteen-lane link.", "This results in differently sized mechanical connections (or “slots”) for each different PCI Express link configuration.", "FIG. 2 shows a comparison of the slot sizes for current 32-bit PCI 2.0, PCI Express ×1 and PCI Express ×16 connector/adapter configurations, respectively.", "It is clear from this figure that a PCI Express adapter can be installed into a slot designed for a larger connection but a not smaller one.", "For example, a PCI Express ×16 adapter will not physically fit into a PCI ×1 connector slot, whereas a PCI Express ×1 adapter can be installed into a PCI ×16 connector slot.", "This compatibility is shown in the table below.", "x1 slot x4 slot x8 slot x16 slot X1 card Supported Supported Supported Supported X4 card No Supported Supported Supported X8 card No No Supported Supported X16 card No No No Supported As explained above, the PCI Express specification allows a device having a larger (or “wider”) bus capacity to be electrically connected to a smaller (or “narrower”) bus, such as for example by connecting a PCI Express ×16 device (having a 16-bit “word”-sized bus architecture) to a PCI Express ×8 (single-byte), ×4 (half-byte), or ×1 (single bit) bus through an adapter.", "However, as illustrated with reference to FIG. 2 , a mechanical limitation exists with each type of PCI Express connector currently used to connect the bus to the device adapter, since the physical dimension(s) of the connector do not support its use with an adapter having a wider bus interface than that of the connector itself.", "As a result, a PCI Express ×16 adapter cannot currently be installed in a PCI Express ×8, ×4, or ×1 connector slot due to this mechanical limitation.", "All current solutions to this problem use a PCI Express connector having a bus width at least as large as that of the installed adapter while wiring only a portion of the connector to the system bus for use with the adapter.", "For example, by wiring only eight (8) of its connections to the system integrated circuit (IC) chipset on the PCB, a PCI Express ×16 connector may be used to connect an 8-bit (single byte-sized) system bus with a PCI Express ×8 or ×16 adapter by installing the adapter into the connector slot.", "However, this solution requires use of a larger, more expensive PCI Express connector taking up a greater amount of space than is necessary for the electrical connection being made, and it results in unused connections.", "The present invention solves these problems by providing a new type of PCI Express connector that allows installation of a PCI Express adapter having a larger bus width than that of the connector itself, by including an opening (or “notch”) in at least one end of the connector to physically accommodate the larger dimension (s) of the adapter.", "As shown in FIGS. 5A-5C , a standard PCI Express connector 10 is modified by adding an opening (or “notch”) 20 to at least one end of the connector slot 15 (such as the one closest to the front of the system).", "The notch 20 allows PCI Express adapters 25 (i.e. “expansion cards”) that are larger in dimension than the connector slot 15 to be installed (or “plugged”) into the connector 10 via the slot, as shown in the example of FIG. 6 where a PCI Express ×16 adapter is installed in a PCI Express ×8 connector slot.", "As shown in FIGS. 5C &", "7B , the notch can extend into the central region of the connector where the metal bus connection pins reside (as well as toward the bottom of the connector) to allow a PCI Express adapter card that is physically larger than the connector to fully seat into the connector as shown in FIG. 6 .", "As shown in FIGS. 7A &", "7B , “outrigger”", "support(s) 30 (made of a material such as plastic) can be added near the end(s) of the PCI Express connector 10 where a notch 20 is included to prevent the connector walls from excessively flexing outward when an adapter 25 is installed, thereby ensuring adequate pressure to complete an electrical connection between the pins inside the connector and the fingers on the expansion card.", "The “outriggers”", "on each side of the connector can be staggered (as shown in FIG. 7A ) to allow multiple “notched”", "PCI Express connectors to be placed next to each other without creating mechanical interference problems.", "Even though a PCI Express ×8 connector is illustrated in the example described herein, the “notch”", "technique can be applied to a PCI Express connector of any size, or to any other expansion connector using an architecture that allows for different bus widths.", "The “notched”", "PCI Express connector of this invention thus overcomes the disadvantages of the prior art by eliminating the problems experienced with current PCI Express connector/adapter configurations, while also allowing the connector to be compliant with the PCI Express specification, and it can be used to manufacture a variety of different PCI Express connectors as well as connectors for other expansion busses.", "While certain preferred features of the invention have been shown by way of illustration, many modifications and changes can be made that fall within the true spirit of the invention as embodied in the following claims, which are to be interpreted as broadly as the law permits to cover the full scope of the invention, including all equivalents thereto." ]
CROSS-REFERENCE TO RELATED APPLICATIONS “This application is a divisional application of U.S. patent application Ser. No. 09/276,015 now U.S. Pat. No. 6,146,713 filed Mar. 25, 1999, which is incorporated herein by reference.” STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT BACKGROUND OF THE INVENTION The present invention is directed generally to communication networks and systems. More particularly, the invention relates to optical WDM systems and optical components employing Bragg gratings, and methods of making Bragg gratings for use therein. Optical communication systems transmit information by generating and sending optical signals corresponding to the information through optical transmission fiber. Information transported by the optical systems can include audio, video, data, or any other information format. The optical systems can be used in telephone, cable television, LAN, WAN, and MAN systems, as well as other communication systems. Information can be optically transmitted using a broad range of frequencies/wavelengths, each of which is suitable for high speed data transmission and is generally unaffected by conditions external to the fiber, such as electrical interference. Also, information can be carried using multiple optical wavelengths that are combined using wavelength division multiplexing (“WDM”) techniques into one optical signal and transmitted through the optical systems. As such, optical fiber transmission systems can provide significantly higher transmission capacities at substantially lower costs than electrical transmission systems. One difficulty that exists with WDM systems is that the various signal wavelengths often have to be separated for routing/switching during transmission and/or reception at the signal destination. In early WDM systems, the wavelength spacing was limited, in part, by the ability to effectively separate wavelengths from the WDM signal at the receiver. Most optical filters in early WDM systems employed a wide pass band filter, which effectively set the minimum spacing of the wavelengths in the WDM system. Diffraction gratings were proposed for use in many transmission devices; however, the use of separate optical components in free space configurations were cumbersome and posed serious problems in application. Likewise, etched optical fiber gratings, while an improvement over diffraction gratings, proved difficult to effectively implement in operating systems. The development of holographically induced fiber Bragg gratings has facilitated the cost effective use of grating technology in operating optical transmission systems. In-fiber Bragg gratings have provided an inexpensive and reliable means to separate closely spaced wavelengths. The use of in-fiber Bragg grating has further improved the viability of WDM systems by enabling direct detection of the individually separated wavelengths. For example, see U.S. Pat. No. 5,077,816 issued to Glomb et al. Holograpically written optical fiber Bragg gratings are well known in the art. See, for instance, U.S. Pat. Nos. 4,725,110 and 4,807,950, which are incorporated herein by reference. Holographic gratings are generally produced exposing an optical waveguide, such a silica-based optical fiber or planar waveguide, to an interference pattern produced by intersecting radiation beams, typically in the ultraviolet frequency range. The intersecting beams can be produced interferometrically using one or more radiation sources or using a phase mask. For examples, see the above references, as well as U.S. Pat. Nos. 5,327,515, 5,351,321, 5,367,588 and 5,745,617, and PCT Publication No. WO 96/36895 and WO 97/21120, which are incorporated herein by reference. Bragg gratings provide a versatile means of separating wavelengths, because the wavelength range, or bandwidth, over which the grating is reflective as well as the reflectivity, can be controlled. Initially, however, only relatively narrow bandwidth, low reflectivity Bragg gratings could be produced using holographic methods. It was soon found that the sensitivity of the waveguide to ultraviolet radiation and the resulting bandwidth and reflectivity could be greatly enhanced by exposing the waveguide to hydrogen and its isotopes before writing the grating. Hydrogenation of the fiber was originally performed as a high temperature annealing process. For example, see, F. Ouellette et al., Applied Physics Letters, Vol. 58(17), p. 1813, (4 hours at 400° C. in 12 atm. of H 2 ) or G. Meltz et al., SPIE International Workshop on Photoinduced Self-Organization in Optical Fiber, May 10-11, 1991, Quebec City, Canada, paper 1516-18 (75 hours at 610° C. in 1 atm. H 2 ). It was later found that the hydrogenation could be performed at lower temperatures ≦250° C. with H 2 pressures ≧1 atm., if a sufficient length of time is permitted for hydrogen to get into the fiber. See U.S. Pat. No. 5,235,659 and its progeny. While low temperature hydrogenation takes longer to perform, presumably due, at least in part, to slower hydrogen diffusion rates, it provides benefits that typically offset the time penalty. For example, the low temperature hydrogenation generally does not damage polymer coatings that are typically used to protect the optical fiber cladding and core. Also, there are fewer safety issues with handling hydrogen at lower temperatures and pressures. Although low temperature hydrogenation is effective for introducing hydrogen into the fiber, the gratings written into the fiber must still be annealed at higher temperatures to stabilize the reflectivity of the grating. See U.S. Pat. Nos. 5,235,659 and 5,620,496. One technique that may increase grating stability written in low temperature hydrogenated fiber is described in OFC'99 PostDeadline Paper PD20 (1999) (“PD20”). In PD20, low temperature hydrogenated fiber was exposed to a uniform UV beam prior to writing grating to vary the fiber structure. In addition, the fiber was low temperature annealed at 125° C. for 24 hours before writing the grating to drive off at least some of the hydrogen from the fiber. The high reflectivity gratings that were written in the low temperature annealed fiber did not vary significantly, when exposed to a subsequent low temperature anneal at 125° C. A shortcoming of writing Bragg gratings in hydrogen loaded fiber is that the fiber is more difficult to splice. Therefore, splicing efficiencies are decreased and increased processes must be put into place to ensure proper handling of the fiber. High temperature annealing of the fiber to remove hydrogen is limited to only portions of the fiber in which the coating has been removed to write the grating. In techniques that do not require the coating to be removed, annealing of the grating is also limited to temperatures that do not damage the coatings. The prominent role assumed by holographically induced Bragg gratings in fiber and other waveguide optical components and systems requires that improved techniques for the production of Bragg gratings be continually developed. Likewise, the improvements in Bragg grating technology will further provide for the continued development of increasingly flexible, higher capacity, and lower cost optical systems. BRIEF SUMMARY OF THE INVENTION The apparatuses and methods of the present invention address the above need for improved Bragg grating production techniques and optical components and systems that include the Bragg gratings. Optical components and transmission system of the present invention includes at least one Bragg grating prepared in accordance with the present invention. In various embodiments, Bragg grating of the present invention are provided to stabilize optical signal and/or pump sources, perform selective filtering in transmission and/or receiving, and other grating based applications as may be known in the art. Methods of the present invention include selectively hydrogenating one or more selected sections of an optical waveguide in general, and particularly optical fiber. Selective hydrogenation can be performed by selectively establishing local conditions in a first environment conducive to introducing greater quantities of hydrogen into selected sections than into non-selected sections, which are maintained in a second environment. The extent of selective hydrogenation and the hydrogen concentration difference between selected and non-selected section of the waveguide is a function of the temperature, pressure, and time of exposure established in the first and second environments. In various embodiments of the present invention, the local temperature in the first environment is elevated to increase the rate of hydrogen ingress into the selected section of the waveguide. Increased ingress rates can be achieved by maintaining the local concentration of hydrogen in the first environment, while applying locally elevated temperatures. The local concentration in the first environment can be maintained at elevated temperatures by configuring a hydrogenation device to include a substantial portion of its volume within the first environment. Alternatively, a compartmentalized hydrogenation device can be used to vary the environmental conditions in the first and second environments within the device. Compartmentalized devices can provide for varying the pressure, hydrogen concentration and/or exposure time in the first and second environments. The difference between the local concentration and temperature along the sections of fiber and the length of exposure generally determines the relative extent of hydrogenation. In various embodiments, the hydrogenation device can be configured such that the heated volume of the first environment proximate to the selected section represents greater than 90% of the total device volume. Increasing the heated volume percentage and/or the local temperature will increase the difference in hydrogenation between the selected section and the remainder of the fiber. Selective hydrogenation can be performed over a wide temperature range. The methods are not limited to low temperatures to prevent damage to the fiber coating, because high temperature selective hydrogenation can be limited to only those sections in which the coating will be removed to write the grating. It is desirable to perform selective hydrogenation at temperatures in excess of 250° C., because the exposure time can be decreased by several orders of magnitude compared to low temperatures. In addition, high pressures, e.g. >200 atm., can be employed to further decrease the exposure time by increasing hydrogen concentration in the device. As such, higher throughput can be achieved and hydrogenation devices do not have to remain charged with hydrogen for extended periods of time. An additional benefit of high temperature selective hydrogenation is that many coatings are easier to remove following exposure to elevated temperatures. The removal of the coating to write the grating also facilitates high temperature annealing to increase the long term stability of the grating characteristics. In addition, the second environment can be controlled to produce varying levels of hydrogenation in the non-selected sections of the waveguide. In fact, extremely low hydrogen concentrations can be achieved in the non-selected when high temperature selective hydrogenation is used, because of the short exposure times. Therefore, the non-selected sections of the fiber can be spliced more easily than traditional methods, which leads to further efficiency increases. Accordingly, the present invention addresses the aforementioned needs for improved Bragg grating production methods to increase the efficiency and capacity of optical components and communication systems without commensurate increases in the cost of optical components. These advantages and others will become apparent from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying Figures wherein like members bear like reference numerals and wherein: FIG. 1 depict optical components and systems of the present invention; and, FIGS. 2-3 depict exemplary hydrogenation devices of the present invention. DETAILED DESCRIPTION OF THE INVENTION The operation of optical systems 10 of the present invention will be described generally with reference to the drawings for the purpose of illustrating embodiments only and not for purposes of limiting the same. As used herein, the term “information” should be broadly construed to include any type of audio signal, video signal, data, instructions, etc. that can be transmitted as optical signals. Also, the term “hydrogen” is meant to include atomic and diatomic hydrogen, H and H 2 , respectively, as well as hydrogen isotopes, such as deuterium. Generally, the optical system 10 includes at least one optical transmitter 12 in optical communication with at least one optical receiver 14 via an optical transmission waveguide 16 , such as optical fiber, as shown in FIG. 1 . Each transmitter 12 is configured to transmit information via one or more information carrying wavelengths λ i,k that be combined into a wavelength division multiplexed (“WDM”) optical signal. The transmitter 12 may include one or more coherent or incoherent optical sources 18 , such as semiconductor and fiber lasers, and associated electronic control circuitry and optics, i.e. lens 20 , as is known in the art. The wavelength emitted by the optical sources 18 can be stabilized or established using Bragg gratings 22 to form an internal and/or external laser cavity. For example, distributed feedback (“DFB”) and Bragg reflector (“DBR”) lasers, and other lasers can include Bragg gratings 22 in both the laser cavity and the external cavity. Likewise, Bragg grating 22 can be used to select wavelengths from broadband sources, such as light emitting diodes. The optical source 18 can be directly modulated with information to be transmitted, or an external modulator 24 can be used to modulate the information onto an optical carrier wavelength provided by the source 18 . Alternatively, the external modulator 24 can be replaced with an optical upconverter to upconvert a modulated electrical carrier onto an optical wavelength different than the optical carrier wavelength emitted by the optical source 18 . The receiver 14 can include Bragg gratings 22 in demultiplexers 26 and/or filters 28 to separate one or more wavelengths from a wavelength division multiplexed (“WDM”) optical signal. The receiver 14 can be configured to coherently or directly detect the selected wavelengths depending upon the system 10 . In addition, the transmitter 12 , receivers 14 , as well as other components, can be wavelength tuned to provide additional flexibility in the system 10 . Wavelength tuning can be performed by varying the reflective wavelength of the Bragg gratings 22 using techniques such as those described in U.S. Pat. No. 5,007,705, and other techniques as is known in the art. Similarly, the Bragg gratings 22 can be used in a multiplexers 30 for combining multiple optical signals and possibly to spectrally shape the optical signals. Bragg gratings 22 can also be employed in optical switches 32 , including optical routers and cross-connects, to switch, add, or drop signal wavelengths between optical paths. The optical switches 32 can be further configured to serve as an add and/or drop device 34 . Combiners 36 and distributors 38 , such as couplers and circulators, deployed in various combinations in the add/drop device 34 to provide for wavelength reuse, as may be appropriate and is known in the art. The system 10 may include one or more optical amplifiers, such as rare earth, i.e., erbium, or other doped fiber, Raman pumped fiber, or semiconductor, to optical regenerate optical signals in the waveguide 16 . Bragg gratings 22 can be used to wavelength stabilize optical pump power provided by a pump laser 42 , as well as to gain flatten is the amplified signal wavelengths in gain flattening filters 44 . Dispersion compensating devices or amplified spontaneous emission “ASE” filters 46 including Bragg gratings 22 can be used in the system 10 . Bragg gratings 22 of the present invention are produced by selectively hydrogenating one or more selected sections of a waveguide 48 . The waveguide 48 can include various waveguide structures in which holographic gratings can be written, such as planar or fiber waveguides. The waveguides 48 in which the Bragg gratings 22 are holographically written can be the same or different geometry and/or composition as the transmission waveguides 16 . Specific examples with respect to selectively hydrogenating optical fiber are provided to more fully explain the invention and not to limit the same. FIGS. 2 and 3 provide exemplary embodiments of selective hydrogenation devices 50 of the present invention. The devices 50 are generally configured to facilitate the establishment of multiple environments within the device 50 . For example, one or more hot zones 50 H and one or more cool zones 50 c can be provided within the device 50 . One of more waveguides 48 are inserted into the device 50 with first sections of the waveguide 48 to be selectively hydrogenated are within the hot zones 50 H . Likewise, second sections that are to be hydrogenated to a lesser extent are positioned within the cool zones 50 C . A first environment can be established to facilitate hydrogenation on the waveguide within the hot zone 50 H , whereas, a second environment can be established to facilitate a different level of hydrogenation within the cool zone 50 C . In various embodiments of the present invention, the local temperature in the first environment is elevated to increase the rate of hydrogen ingress into the selected section of the waveguide. Increased ingress rates can be achieved by maintaining the local concentration of hydrogen in the first environment, while applying locally elevated temperatures. The local concentration in the first environment can be maintained at elevated temperatures by configuring a hydrogenation device to include a substantial portion of its volume within the first environment. The change in concentration within the first environment at elevated temperature is proportional to the percentage of the total volume within the first environment. Therefore, it is generally desirable to provide as much of the total volume in the first environment as possible. For example, if the volume in the first environment is ten times greater than volume in the second environment, the local concentration in the first environment at 300° C. will decrease less than ˜10% relative to the second environment at ambient temperatures. The amount of hydrogen available to hydrogenate the waveguide 48 is directly proportional to the hydrogen pressure introduced in the hydrogenation device 50 . Therefore, increasing the hydrogen pressure in the device 50 can reduce the hydrogenation time. High pressure hydrogen devices 50 and corresponding sources 52 are available to allow hydrogen pressure exceeding 3000 psi to be introduced into and maintained in the devices 50 . While high pressure hydrogen presents an increased safety concern, the time in which the device So must be maintained under pressure are substantially decreased. It is noted that selective hydrogenation was performed using commercial hydrogen tanks as the source 52 , which are typically charged at 3000 psi ± gage error for delivery. Selective hydrogenation can be performed at higher or lower pressures depending upon available hydrogen sources 52 and the time available to perform the selective hydrogenation. It will be appreciated that different environment can be established within the hot and cool zones to produce different hydrogenation levels, or hydrogen concentrations, within the waveguide 48 in each zone. Also, the cool zones 50 C can be actively heated or cooled depending upon the desirable levels of hydrogenation. It may also be desirable to bring the sections of small dimensioned waveguides 48 into thermal contact with the walls of the device 50 in the cool zones 50 C . Thermal contact will allow more precise and efficient temperature control of the waveguides 48 in the cool zone 50 C . Alternatively, the device 50 can be configured such that one environment is established within the device and only that section of the waveguide 48 to be selectively hydrogenated is within the device 50 . The device 50 shown in FIG. 2 can be tubular in design with a cross-sectional geometry appropriate for the waveguide(s) 48 to be selectively hydrogenated. The cross sectional shape of the device 50 also depends on the system pressure at which the hydrogenation will be performed. A circular cross-section for the device 50 is generally suitable for high pressure hydrogenation methods. In the operation of the device 50 , the waveguide 48 is placed into the device 50 , such that sections to be selectively hydrogenated are placed within one of the hot zones 50 H . The device 50 is sealed and the air within the device 50 is evacuated and/or purged with a gas that will not substantially affect the waveguide 48 , such as nitrogen. Hydrogen can be used to purge the device 50 , although it is generally desirable to use a less expensive purge gas. The hydrogen and purge gases are introduced from a gas source 52 through a valve 54 into the device and a second valve is provided to remove the gases. Conditions in the first and second environments are established for a requisite period of time to perform the selective hydrogenation. Following the selective hydrogenation the device is cooled, the system pressure and temperature are lowered to ambient, if necessary, and the waveguides 48 are removed from the device 50 . It will be appreciated that the hydrogen and purge gases can be recycled as may be appropriate. Recycling becomes a greater economic concern when expensive hydrogen isotopes, such as deuterium are used. The embodiment shown in FIG. 2 can result in a substantial linear distance between the hot zones and the cool zones. Given the small volumes associated with the cool zone, additional temperature control over the cool zone may not be required, if ambient cool zone temperatures are acceptable. In fact, it may be possible to place additional lengths of fiber on a spool 56 to facilitate fiber loading into the device 50 without multiple exposures substantially affecting the additional fiber on the spool 56 . A thermal and/or pressure barrier 58 can be used to segregate the hot and cool zones and/or high and low pressure zones in the device 50 , such as shown in FIG. 3 . Fiber sections that are to be selectively hydrogenated are passed through the barrier 58 into the hot zone 50 H , while the rest of the fiber 48 remains in the cool zone 50 C . The thermal barriers 48 can be fabricated using any appropriate insulating materials, such as alumina, zirconia and other suitable materials. When the barrier 48 is configured as a pressure boundary, selective hydrogenation can be performed by varying the pressure, hydrogen concentration, and exposure time, in addition to or in lieu of the temperature. In the hot zone 50 H , a heat exchanger 60 can be provided to introduce heat Q into the device 50 . The temperature in the hot zone 50 H can be monitored using thermocouples and the heat exchanger 60 controlled to maintain a desired temperature as is known in the art. It may also be desirable to provide additional heat exchangers 60 to maintain a desired temperature in the cool zones 50 C of the device 50 , as well as any zone interface regions. The precise conditions at which the selective hydrogenation is performed depend upon the desired characteristics in the Bragg grating to be written into the waveguide 48 , the production requirements, and the capabilities of the skilled artisan. A number of examples are provided to provide an appreciation of the value of the significant parameters. Bragg gratings can be written using the various techniques set forth in the above references. The precise technique used to write the gratings 22 may depend upon the characteristics of the grating 22 . The gratings 22 can be written using a stationary apparatus and laser with a beam size sufficiently large to write the entire grating at one time. Alternatively, scanning apparatuses can be employed to control the length, reflectivity, reflective wavelengths, and/or other characteristics of the gratings. For example, the grating characteristics can be controlled by providing relative movement, either at a constant or varying rate, unidirectional or dithering, between the waveguide 48 and the interference pattern. The Bragg grating 22 can be annealed to groom and stabilize the grating characteristics, such as bandwidth and. reflectivity, and center reflective wavelength. Generally, the gratings 22 are annealed at a sufficiently high temperature, i.e., 300° C., to ensure stable grating characteristics. Annealing will generally reduce the bandwidth and reflectivity of the grating and vary the reflective wavelength. Therefore, it may be desirable to write the Bragg gratings such that the desired grating characteristics will be achieved upon annealing. An embodiment of the device 50 was constructed using 316 stainless steel tubing and Swagelok™ fittings, as generally shown in FIG. 2, but without the fiber source/spool 56 . Selectively hydrogenation of various fiber types, including Ge and Ge/B doped fibers, was performed with the cool zone 50 C exposed to ambient temperatures without additional control and the conditions shown in the table below. Bragg gratings 22 were written into the fiber using a scanning UV beam having a wavelength of 244 nm and phase mask using conventional techniques as previously described. Bragg gratings written in the unhydrogenated fiber and fiber exposed to the ambient second environment had a 0.28 nm bandwidth at −1 dB from the center wavelength. Whereas, Bragg gratings written in the fiber that was selectively hydrogenated at 300° C. and ˜3000 psi had increased reflective bandwidths for all first (heated) to second (unheated) environment volume ratios tested. For example, Bragg gratings written in fibers that were selectively hydrogenated at 300° C. and ˜3000 psi in devices having heated to unheated volume ratios of 1:20 and 2:1. The gratings written in the selectively hydrogenated fiber had reflective bandwidths of 1.1 nm and 2.2 nm, respectively at −1 dB. Similar results were achieved for selectively hydrogenation was performed for 15 and 30 minutes. Depending upon the temperature and time conditions selected to perform the hydrogenation, it may be necessary to mark the section that is to be hydrogenated. This is not necessary in the prior art, because the entire fiber was hydrogenated to essentially the same concentration. An additional benefit of selectively hydrogenating is that at temperatures that affect the coating on the fiber, such as by turning it brown, the selectively hydrogenated section can be easily identified by temperature induced coating variations. As indicated by the above results, selective hydrogenation can shorten the hydrogenation time by an order of magnitude or more compared with prior art processes. The increased throughput that can be achieved using the present invention can result in substantial savings in terms of facility and staffing requirements. Those of ordinary skill in the art will appreciate that numerous modifications and variations that can be made to specific aspects of the present invention without departing from the scope of the present invention. It is intended that the foregoing specification and the following claims cover such modifications and variations.
Apparatuses, systems, and methods are disclosed for providing optical communications. Bragg grating used in the optical components and systems of the present invention are produced by selectively hydrogenating one or more selected sections of an optical waveguide in general, and particularly optical fiber. Selective hydrogenation can be performed by selectively establishing local conditions in a first environment conducive to introducing greater quantities of hydrogen into selected sections than into non-selected sections, which are maintained in a second environment. The extent of selective hydrogenation and the hydrogen concentration difference between selected and non-selected section of the waveguide is a function of the temperature, pressure, and time of exposure established in the first and second environments.
Briefly outline the background technology and the problem the invention aims to solve.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS “This application is a divisional application of U.S. patent application Ser. No. 09/276,015 now U.S. Pat. No. 6,146,713 filed Mar. 25, 1999, which is incorporated herein by reference.”", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT BACKGROUND OF THE INVENTION The present invention is directed generally to communication networks and systems.", "More particularly, the invention relates to optical WDM systems and optical components employing Bragg gratings, and methods of making Bragg gratings for use therein.", "Optical communication systems transmit information by generating and sending optical signals corresponding to the information through optical transmission fiber.", "Information transported by the optical systems can include audio, video, data, or any other information format.", "The optical systems can be used in telephone, cable television, LAN, WAN, and MAN systems, as well as other communication systems.", "Information can be optically transmitted using a broad range of frequencies/wavelengths, each of which is suitable for high speed data transmission and is generally unaffected by conditions external to the fiber, such as electrical interference.", "Also, information can be carried using multiple optical wavelengths that are combined using wavelength division multiplexing (“WDM”) techniques into one optical signal and transmitted through the optical systems.", "As such, optical fiber transmission systems can provide significantly higher transmission capacities at substantially lower costs than electrical transmission systems.", "One difficulty that exists with WDM systems is that the various signal wavelengths often have to be separated for routing/switching during transmission and/or reception at the signal destination.", "In early WDM systems, the wavelength spacing was limited, in part, by the ability to effectively separate wavelengths from the WDM signal at the receiver.", "Most optical filters in early WDM systems employed a wide pass band filter, which effectively set the minimum spacing of the wavelengths in the WDM system.", "Diffraction gratings were proposed for use in many transmission devices;", "however, the use of separate optical components in free space configurations were cumbersome and posed serious problems in application.", "Likewise, etched optical fiber gratings, while an improvement over diffraction gratings, proved difficult to effectively implement in operating systems.", "The development of holographically induced fiber Bragg gratings has facilitated the cost effective use of grating technology in operating optical transmission systems.", "In-fiber Bragg gratings have provided an inexpensive and reliable means to separate closely spaced wavelengths.", "The use of in-fiber Bragg grating has further improved the viability of WDM systems by enabling direct detection of the individually separated wavelengths.", "For example, see U.S. Pat. No. 5,077,816 issued to Glomb et al.", "Holograpically written optical fiber Bragg gratings are well known in the art.", "See, for instance, U.S. Pat. Nos. 4,725,110 and 4,807,950, which are incorporated herein by reference.", "Holographic gratings are generally produced exposing an optical waveguide, such a silica-based optical fiber or planar waveguide, to an interference pattern produced by intersecting radiation beams, typically in the ultraviolet frequency range.", "The intersecting beams can be produced interferometrically using one or more radiation sources or using a phase mask.", "For examples, see the above references, as well as U.S. Pat. Nos. 5,327,515, 5,351,321, 5,367,588 and 5,745,617, and PCT Publication No. WO 96/36895 and WO 97/21120, which are incorporated herein by reference.", "Bragg gratings provide a versatile means of separating wavelengths, because the wavelength range, or bandwidth, over which the grating is reflective as well as the reflectivity, can be controlled.", "Initially, however, only relatively narrow bandwidth, low reflectivity Bragg gratings could be produced using holographic methods.", "It was soon found that the sensitivity of the waveguide to ultraviolet radiation and the resulting bandwidth and reflectivity could be greatly enhanced by exposing the waveguide to hydrogen and its isotopes before writing the grating.", "Hydrogenation of the fiber was originally performed as a high temperature annealing process.", "For example, see, F. Ouellette et al.", ", Applied Physics Letters, Vol. 58(17), p. 1813, (4 hours at 400° C. in 12 atm.", "of H 2 ) or G. Meltz et al.", ", SPIE International Workshop on Photoinduced Self-Organization in Optical Fiber, May 10-11, 1991, Quebec City, Canada, paper 1516-18 (75 hours at 610° C. in 1 atm.", "H 2 ).", "It was later found that the hydrogenation could be performed at lower temperatures ≦250° C. with H 2 pressures ≧1 atm.", ", if a sufficient length of time is permitted for hydrogen to get into the fiber.", "See U.S. Pat. No. 5,235,659 and its progeny.", "While low temperature hydrogenation takes longer to perform, presumably due, at least in part, to slower hydrogen diffusion rates, it provides benefits that typically offset the time penalty.", "For example, the low temperature hydrogenation generally does not damage polymer coatings that are typically used to protect the optical fiber cladding and core.", "Also, there are fewer safety issues with handling hydrogen at lower temperatures and pressures.", "Although low temperature hydrogenation is effective for introducing hydrogen into the fiber, the gratings written into the fiber must still be annealed at higher temperatures to stabilize the reflectivity of the grating.", "See U.S. Pat. Nos. 5,235,659 and 5,620,496.", "One technique that may increase grating stability written in low temperature hydrogenated fiber is described in OFC'99 PostDeadline Paper PD20 (1999) (“PD20”).", "In PD20, low temperature hydrogenated fiber was exposed to a uniform UV beam prior to writing grating to vary the fiber structure.", "In addition, the fiber was low temperature annealed at 125° C. for 24 hours before writing the grating to drive off at least some of the hydrogen from the fiber.", "The high reflectivity gratings that were written in the low temperature annealed fiber did not vary significantly, when exposed to a subsequent low temperature anneal at 125° C. A shortcoming of writing Bragg gratings in hydrogen loaded fiber is that the fiber is more difficult to splice.", "Therefore, splicing efficiencies are decreased and increased processes must be put into place to ensure proper handling of the fiber.", "High temperature annealing of the fiber to remove hydrogen is limited to only portions of the fiber in which the coating has been removed to write the grating.", "In techniques that do not require the coating to be removed, annealing of the grating is also limited to temperatures that do not damage the coatings.", "The prominent role assumed by holographically induced Bragg gratings in fiber and other waveguide optical components and systems requires that improved techniques for the production of Bragg gratings be continually developed.", "Likewise, the improvements in Bragg grating technology will further provide for the continued development of increasingly flexible, higher capacity, and lower cost optical systems.", "BRIEF SUMMARY OF THE INVENTION The apparatuses and methods of the present invention address the above need for improved Bragg grating production techniques and optical components and systems that include the Bragg gratings.", "Optical components and transmission system of the present invention includes at least one Bragg grating prepared in accordance with the present invention.", "In various embodiments, Bragg grating of the present invention are provided to stabilize optical signal and/or pump sources, perform selective filtering in transmission and/or receiving, and other grating based applications as may be known in the art.", "Methods of the present invention include selectively hydrogenating one or more selected sections of an optical waveguide in general, and particularly optical fiber.", "Selective hydrogenation can be performed by selectively establishing local conditions in a first environment conducive to introducing greater quantities of hydrogen into selected sections than into non-selected sections, which are maintained in a second environment.", "The extent of selective hydrogenation and the hydrogen concentration difference between selected and non-selected section of the waveguide is a function of the temperature, pressure, and time of exposure established in the first and second environments.", "In various embodiments of the present invention, the local temperature in the first environment is elevated to increase the rate of hydrogen ingress into the selected section of the waveguide.", "Increased ingress rates can be achieved by maintaining the local concentration of hydrogen in the first environment, while applying locally elevated temperatures.", "The local concentration in the first environment can be maintained at elevated temperatures by configuring a hydrogenation device to include a substantial portion of its volume within the first environment.", "Alternatively, a compartmentalized hydrogenation device can be used to vary the environmental conditions in the first and second environments within the device.", "Compartmentalized devices can provide for varying the pressure, hydrogen concentration and/or exposure time in the first and second environments.", "The difference between the local concentration and temperature along the sections of fiber and the length of exposure generally determines the relative extent of hydrogenation.", "In various embodiments, the hydrogenation device can be configured such that the heated volume of the first environment proximate to the selected section represents greater than 90% of the total device volume.", "Increasing the heated volume percentage and/or the local temperature will increase the difference in hydrogenation between the selected section and the remainder of the fiber.", "Selective hydrogenation can be performed over a wide temperature range.", "The methods are not limited to low temperatures to prevent damage to the fiber coating, because high temperature selective hydrogenation can be limited to only those sections in which the coating will be removed to write the grating.", "It is desirable to perform selective hydrogenation at temperatures in excess of 250° C., because the exposure time can be decreased by several orders of magnitude compared to low temperatures.", "In addition, high pressures, e.g. >200 atm.", ", can be employed to further decrease the exposure time by increasing hydrogen concentration in the device.", "As such, higher throughput can be achieved and hydrogenation devices do not have to remain charged with hydrogen for extended periods of time.", "An additional benefit of high temperature selective hydrogenation is that many coatings are easier to remove following exposure to elevated temperatures.", "The removal of the coating to write the grating also facilitates high temperature annealing to increase the long term stability of the grating characteristics.", "In addition, the second environment can be controlled to produce varying levels of hydrogenation in the non-selected sections of the waveguide.", "In fact, extremely low hydrogen concentrations can be achieved in the non-selected when high temperature selective hydrogenation is used, because of the short exposure times.", "Therefore, the non-selected sections of the fiber can be spliced more easily than traditional methods, which leads to further efficiency increases.", "Accordingly, the present invention addresses the aforementioned needs for improved Bragg grating production methods to increase the efficiency and capacity of optical components and communication systems without commensurate increases in the cost of optical components.", "These advantages and others will become apparent from the following detailed description.", "BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying Figures wherein like members bear like reference numerals and wherein: FIG. 1 depict optical components and systems of the present invention;", "and, FIGS. 2-3 depict exemplary hydrogenation devices of the present invention.", "DETAILED DESCRIPTION OF THE INVENTION The operation of optical systems 10 of the present invention will be described generally with reference to the drawings for the purpose of illustrating embodiments only and not for purposes of limiting the same.", "As used herein, the term “information”", "should be broadly construed to include any type of audio signal, video signal, data, instructions, etc.", "that can be transmitted as optical signals.", "Also, the term “hydrogen”", "is meant to include atomic and diatomic hydrogen, H and H 2 , respectively, as well as hydrogen isotopes, such as deuterium.", "Generally, the optical system 10 includes at least one optical transmitter 12 in optical communication with at least one optical receiver 14 via an optical transmission waveguide 16 , such as optical fiber, as shown in FIG. 1 .", "Each transmitter 12 is configured to transmit information via one or more information carrying wavelengths λ i,k that be combined into a wavelength division multiplexed (“WDM”) optical signal.", "The transmitter 12 may include one or more coherent or incoherent optical sources 18 , such as semiconductor and fiber lasers, and associated electronic control circuitry and optics, i.e. lens 20 , as is known in the art.", "The wavelength emitted by the optical sources 18 can be stabilized or established using Bragg gratings 22 to form an internal and/or external laser cavity.", "For example, distributed feedback (“DFB”) and Bragg reflector (“DBR”) lasers, and other lasers can include Bragg gratings 22 in both the laser cavity and the external cavity.", "Likewise, Bragg grating 22 can be used to select wavelengths from broadband sources, such as light emitting diodes.", "The optical source 18 can be directly modulated with information to be transmitted, or an external modulator 24 can be used to modulate the information onto an optical carrier wavelength provided by the source 18 .", "Alternatively, the external modulator 24 can be replaced with an optical upconverter to upconvert a modulated electrical carrier onto an optical wavelength different than the optical carrier wavelength emitted by the optical source 18 .", "The receiver 14 can include Bragg gratings 22 in demultiplexers 26 and/or filters 28 to separate one or more wavelengths from a wavelength division multiplexed (“WDM”) optical signal.", "The receiver 14 can be configured to coherently or directly detect the selected wavelengths depending upon the system 10 .", "In addition, the transmitter 12 , receivers 14 , as well as other components, can be wavelength tuned to provide additional flexibility in the system 10 .", "Wavelength tuning can be performed by varying the reflective wavelength of the Bragg gratings 22 using techniques such as those described in U.S. Pat. No. 5,007,705, and other techniques as is known in the art.", "Similarly, the Bragg gratings 22 can be used in a multiplexers 30 for combining multiple optical signals and possibly to spectrally shape the optical signals.", "Bragg gratings 22 can also be employed in optical switches 32 , including optical routers and cross-connects, to switch, add, or drop signal wavelengths between optical paths.", "The optical switches 32 can be further configured to serve as an add and/or drop device 34 .", "Combiners 36 and distributors 38 , such as couplers and circulators, deployed in various combinations in the add/drop device 34 to provide for wavelength reuse, as may be appropriate and is known in the art.", "The system 10 may include one or more optical amplifiers, such as rare earth, i.e., erbium, or other doped fiber, Raman pumped fiber, or semiconductor, to optical regenerate optical signals in the waveguide 16 .", "Bragg gratings 22 can be used to wavelength stabilize optical pump power provided by a pump laser 42 , as well as to gain flatten is the amplified signal wavelengths in gain flattening filters 44 .", "Dispersion compensating devices or amplified spontaneous emission “ASE”", "filters 46 including Bragg gratings 22 can be used in the system 10 .", "Bragg gratings 22 of the present invention are produced by selectively hydrogenating one or more selected sections of a waveguide 48 .", "The waveguide 48 can include various waveguide structures in which holographic gratings can be written, such as planar or fiber waveguides.", "The waveguides 48 in which the Bragg gratings 22 are holographically written can be the same or different geometry and/or composition as the transmission waveguides 16 .", "Specific examples with respect to selectively hydrogenating optical fiber are provided to more fully explain the invention and not to limit the same.", "FIGS. 2 and 3 provide exemplary embodiments of selective hydrogenation devices 50 of the present invention.", "The devices 50 are generally configured to facilitate the establishment of multiple environments within the device 50 .", "For example, one or more hot zones 50 H and one or more cool zones 50 c can be provided within the device 50 .", "One of more waveguides 48 are inserted into the device 50 with first sections of the waveguide 48 to be selectively hydrogenated are within the hot zones 50 H .", "Likewise, second sections that are to be hydrogenated to a lesser extent are positioned within the cool zones 50 C .", "A first environment can be established to facilitate hydrogenation on the waveguide within the hot zone 50 H , whereas, a second environment can be established to facilitate a different level of hydrogenation within the cool zone 50 C .", "In various embodiments of the present invention, the local temperature in the first environment is elevated to increase the rate of hydrogen ingress into the selected section of the waveguide.", "Increased ingress rates can be achieved by maintaining the local concentration of hydrogen in the first environment, while applying locally elevated temperatures.", "The local concentration in the first environment can be maintained at elevated temperatures by configuring a hydrogenation device to include a substantial portion of its volume within the first environment.", "The change in concentration within the first environment at elevated temperature is proportional to the percentage of the total volume within the first environment.", "Therefore, it is generally desirable to provide as much of the total volume in the first environment as possible.", "For example, if the volume in the first environment is ten times greater than volume in the second environment, the local concentration in the first environment at 300° C. will decrease less than ˜10% relative to the second environment at ambient temperatures.", "The amount of hydrogen available to hydrogenate the waveguide 48 is directly proportional to the hydrogen pressure introduced in the hydrogenation device 50 .", "Therefore, increasing the hydrogen pressure in the device 50 can reduce the hydrogenation time.", "High pressure hydrogen devices 50 and corresponding sources 52 are available to allow hydrogen pressure exceeding 3000 psi to be introduced into and maintained in the devices 50 .", "While high pressure hydrogen presents an increased safety concern, the time in which the device So must be maintained under pressure are substantially decreased.", "It is noted that selective hydrogenation was performed using commercial hydrogen tanks as the source 52 , which are typically charged at 3000 psi ± gage error for delivery.", "Selective hydrogenation can be performed at higher or lower pressures depending upon available hydrogen sources 52 and the time available to perform the selective hydrogenation.", "It will be appreciated that different environment can be established within the hot and cool zones to produce different hydrogenation levels, or hydrogen concentrations, within the waveguide 48 in each zone.", "Also, the cool zones 50 C can be actively heated or cooled depending upon the desirable levels of hydrogenation.", "It may also be desirable to bring the sections of small dimensioned waveguides 48 into thermal contact with the walls of the device 50 in the cool zones 50 C .", "Thermal contact will allow more precise and efficient temperature control of the waveguides 48 in the cool zone 50 C .", "Alternatively, the device 50 can be configured such that one environment is established within the device and only that section of the waveguide 48 to be selectively hydrogenated is within the device 50 .", "The device 50 shown in FIG. 2 can be tubular in design with a cross-sectional geometry appropriate for the waveguide(s) 48 to be selectively hydrogenated.", "The cross sectional shape of the device 50 also depends on the system pressure at which the hydrogenation will be performed.", "A circular cross-section for the device 50 is generally suitable for high pressure hydrogenation methods.", "In the operation of the device 50 , the waveguide 48 is placed into the device 50 , such that sections to be selectively hydrogenated are placed within one of the hot zones 50 H .", "The device 50 is sealed and the air within the device 50 is evacuated and/or purged with a gas that will not substantially affect the waveguide 48 , such as nitrogen.", "Hydrogen can be used to purge the device 50 , although it is generally desirable to use a less expensive purge gas.", "The hydrogen and purge gases are introduced from a gas source 52 through a valve 54 into the device and a second valve is provided to remove the gases.", "Conditions in the first and second environments are established for a requisite period of time to perform the selective hydrogenation.", "Following the selective hydrogenation the device is cooled, the system pressure and temperature are lowered to ambient, if necessary, and the waveguides 48 are removed from the device 50 .", "It will be appreciated that the hydrogen and purge gases can be recycled as may be appropriate.", "Recycling becomes a greater economic concern when expensive hydrogen isotopes, such as deuterium are used.", "The embodiment shown in FIG. 2 can result in a substantial linear distance between the hot zones and the cool zones.", "Given the small volumes associated with the cool zone, additional temperature control over the cool zone may not be required, if ambient cool zone temperatures are acceptable.", "In fact, it may be possible to place additional lengths of fiber on a spool 56 to facilitate fiber loading into the device 50 without multiple exposures substantially affecting the additional fiber on the spool 56 .", "A thermal and/or pressure barrier 58 can be used to segregate the hot and cool zones and/or high and low pressure zones in the device 50 , such as shown in FIG. 3 .", "Fiber sections that are to be selectively hydrogenated are passed through the barrier 58 into the hot zone 50 H , while the rest of the fiber 48 remains in the cool zone 50 C .", "The thermal barriers 48 can be fabricated using any appropriate insulating materials, such as alumina, zirconia and other suitable materials.", "When the barrier 48 is configured as a pressure boundary, selective hydrogenation can be performed by varying the pressure, hydrogen concentration, and exposure time, in addition to or in lieu of the temperature.", "In the hot zone 50 H , a heat exchanger 60 can be provided to introduce heat Q into the device 50 .", "The temperature in the hot zone 50 H can be monitored using thermocouples and the heat exchanger 60 controlled to maintain a desired temperature as is known in the art.", "It may also be desirable to provide additional heat exchangers 60 to maintain a desired temperature in the cool zones 50 C of the device 50 , as well as any zone interface regions.", "The precise conditions at which the selective hydrogenation is performed depend upon the desired characteristics in the Bragg grating to be written into the waveguide 48 , the production requirements, and the capabilities of the skilled artisan.", "A number of examples are provided to provide an appreciation of the value of the significant parameters.", "Bragg gratings can be written using the various techniques set forth in the above references.", "The precise technique used to write the gratings 22 may depend upon the characteristics of the grating 22 .", "The gratings 22 can be written using a stationary apparatus and laser with a beam size sufficiently large to write the entire grating at one time.", "Alternatively, scanning apparatuses can be employed to control the length, reflectivity, reflective wavelengths, and/or other characteristics of the gratings.", "For example, the grating characteristics can be controlled by providing relative movement, either at a constant or varying rate, unidirectional or dithering, between the waveguide 48 and the interference pattern.", "The Bragg grating 22 can be annealed to groom and stabilize the grating characteristics, such as bandwidth and.", "reflectivity, and center reflective wavelength.", "Generally, the gratings 22 are annealed at a sufficiently high temperature, i.e., 300° C., to ensure stable grating characteristics.", "Annealing will generally reduce the bandwidth and reflectivity of the grating and vary the reflective wavelength.", "Therefore, it may be desirable to write the Bragg gratings such that the desired grating characteristics will be achieved upon annealing.", "An embodiment of the device 50 was constructed using 316 stainless steel tubing and Swagelok™ fittings, as generally shown in FIG. 2, but without the fiber source/spool 56 .", "Selectively hydrogenation of various fiber types, including Ge and Ge/B doped fibers, was performed with the cool zone 50 C exposed to ambient temperatures without additional control and the conditions shown in the table below.", "Bragg gratings 22 were written into the fiber using a scanning UV beam having a wavelength of 244 nm and phase mask using conventional techniques as previously described.", "Bragg gratings written in the unhydrogenated fiber and fiber exposed to the ambient second environment had a 0.28 nm bandwidth at −1 dB from the center wavelength.", "Whereas, Bragg gratings written in the fiber that was selectively hydrogenated at 300° C. and ˜3000 psi had increased reflective bandwidths for all first (heated) to second (unheated) environment volume ratios tested.", "For example, Bragg gratings written in fibers that were selectively hydrogenated at 300° C. and ˜3000 psi in devices having heated to unheated volume ratios of 1:20 and 2:1.", "The gratings written in the selectively hydrogenated fiber had reflective bandwidths of 1.1 nm and 2.2 nm, respectively at −1 dB.", "Similar results were achieved for selectively hydrogenation was performed for 15 and 30 minutes.", "Depending upon the temperature and time conditions selected to perform the hydrogenation, it may be necessary to mark the section that is to be hydrogenated.", "This is not necessary in the prior art, because the entire fiber was hydrogenated to essentially the same concentration.", "An additional benefit of selectively hydrogenating is that at temperatures that affect the coating on the fiber, such as by turning it brown, the selectively hydrogenated section can be easily identified by temperature induced coating variations.", "As indicated by the above results, selective hydrogenation can shorten the hydrogenation time by an order of magnitude or more compared with prior art processes.", "The increased throughput that can be achieved using the present invention can result in substantial savings in terms of facility and staffing requirements.", "Those of ordinary skill in the art will appreciate that numerous modifications and variations that can be made to specific aspects of the present invention without departing from the scope of the present invention.", "It is intended that the foregoing specification and the following claims cover such modifications and variations." ]
BACKGROUND OF THE INVENTION A patient data set and an operating site during surgery are typically referenced to each other by using either anatomical indicia or—before an image data set is created—implants (bone or skin markers) that are applied to the patient. The implants are indicated simultaneously with an input device at a workstation and with a localization system on the patient. A more general task relates to referencing between a data set (which describes geometrically the spatial model of a body) and the real physical environment in which the actual body is placed. For referencing, a three-dimensional position reference body is used on or applied to the real body. The position reference body consists of one or more elementary bodies (markers) whose 3-dimensional position can be detected with sensors and which define a fixed geometric reference with respect to the center of gravity of the body or to other reference volumes of the body. For the purpose of registration, the position reference body and/or its elementary bodies are correlated in the data model and in the physical world. Unlike the present method, the German patent DE 197 47 427 describes a method and a device wherein the characteristic surface of bone structures is used for providing a reference between a data set and the operating site. DE 197 47 427 describes an individual template which carries 3-D localization markers and is applied to and/or screwed on a bone segment. The method has the disadvantage that an expensive CAD-CAM model has to be produced from a patient data set before an individual template can be manufactured. With many surgical procedures, large areas of bone have to be exposed for applying the individual surface template, which makes the procedure unnecessarily invasive. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and a device for instrument, bone segment, tissue and organ navigation, which operates without auxiliary devices, such as templates, and facilitates a safe and reproducible navigation. By using optical measurements and by referencing the operating site via the characteristic surface of a soft tissue envelope or a bone surface, the cost can be reduced significantly and the surgical access path can be significantly less invasive. For a bone segment navigation with the present invention, the 3-D localization markers can be individually secured on a bone segment independent of a template—such as a screw, which opens additional possibilities for a minimally-invasive surgical procedure. Optical referencing between the data set, the operating site and the 3-D localization markers is also faster and more precise than the aforedescribed referencing method that uses anatomical indicia and implants, because large surface structures in a patient data set (for example MRT or CT) can be imaged more exactly and reproduced than small, singular reference points. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention are illustrated in the drawings and will be described hereinafter in more detail. It is shown in FIG. 1 a schematic diagram of the devices in an operating room, FIG. 2 a detailed view of the 3-D reference markers with a device for detecting these markers by optical methods using 3-D scanners, FIG. 3 a geometric device for optical detection of 3-D reference markers, which are affixed to a frame, FIG. 4 a perspective view of the 3-D reference markers with associated geometric devices of different form (depression/sulcus, raised portion/crista, planar color-coded surface) for optical detection with the 3-D scanner, FIG. 5 alternative examples of different geometric forms that have a known spatial association with the 3-D marker, FIG. 6 additional coupled referencing markers, FIG. 7 an embodiment with a different coupling between the scanner and position detection unit, FIG. 8 referencing of bodies that do not necessarily have a stable form, and FIG. 9 device for positioning bodies that do not necessarily have a stable form. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will be described hereinafter in more detail with reference to a first embodiment. The entire system 1 is used for optical referencing between an operating site, a patient data set and 3-D markers. An optical 3-D scanner 5 is attached to a position detection unit 4 via a coupling device 13 . The position detection unit 4 can acquire, for example, infrared signals, ultrasound signals or electromagnetic signals and allows the determination of three-dimensional coordinates of a corresponding 3-D marker 6 (for example: ultrasound transmitter, infrared transmitter, electromagnetic transmitter and/or reflectors 17 for all types of waves, ultrasound, infrared, radar, etc.). The 3-D scanner 5 (for example a 3-D laser scanner 5 or a radar unit 5 a ) can detect the shape and color of surfaces (for example 7 ), but not the signals from the 3-D markers 6 . The signals from the 3-D markers 6 can be transmitted actively, for example with an LED, or passively, for example by using reflectors. The data measured by the position detection unit 4 and the 3-D scanner 5 or the radar unit 5 a are transmitted via a connection 10 and 11 to a display and processing unit 2 . Since the position detection unit 4 and the 3-D scanner 5 are coupled via a connection 13 having a known geometrical relationship and/or are kinematically attached to each other via a connection 13 , all coordinates measured with the position detection unit 4 can also be expressed in the coordinate system of the 3-D scanner 5 and vice versa. A planning unit 3 is connected via 12 to the display and processing unit 2 . Surgical procedures can be simulated on this planning unit 3 ; for example, resetting osteotomies can be planned before a bone segment navigation. In this embodiment, at least three 3-D markers 6 are attached to the patient, which define a coordinate system on the patient. Geometric FIGS. 7 which can be detetced by the 3-D scanner 5 , are arranged in a known, fixed spatial relationship to these 3-D markers 6 . These FIGS. 7 can be implemented, for example, as a depression/sulcus 7 a, a raised portion/crista 7 b, as color-coded lines and fields 7 c or as a bar code. The geometric FIG. 7 can also be in the form of a base on which a 3-D marker 6 is placed. The geometric FIG. 7 can also be formed directly by one or several 3-D markers 6 . The coordinates of the 3-D markers 6 can be uniquely determined by processing unit 2 from the geometry of the devices 7 by an inverse transformation. The geometry of these devices 7 can be different ( 7 ′, 7 ″, 7 ′″); it is only necessary that the geometry can be detected by the 3-D scanner 5 and that the processing unit 2 can determine the coordinates of the 3-D markers 6 from the geometry of the devices 7 . If the three 3-D markers 6 are fixedly connected with one another by a frame 14 in order to define a patient coordinate system, then the coordinates of the 3-D markers 6 can be determined by the processing unit 2 from the arrangement of the geometric FIGS. 7 on the frame 14 . Alternatively, the scanner can also determine the coordinates directly by the analyzing the known geometries of the 3-D markers. The operating site, the patient data set and the 3-D markers 6 are referenced to each other by first detecting with the 3-D scanner 5 the soft tissue (before the surgery, i.e., before the soft tissue swells or is displaced) or the bone surfaces 9 of the patient. The processing unit 2 processes the data from the 3-D scanner 5 and determines the most advantageous surface area fit between the patient and the patient data set. Thereafter, the patient and the patient data set can be referenced to each other by a coordinate transformation. So far, however, the 3-D scanner 5 has not yet detected the 3-D markers 6 . However, since the geometric devices 7 surrounding the 3-D markers 6 were scanned together with the patient and since the spatial relationship between the 3-D markers 6 and the geometric devices 7 is known, the coordinates of the 3-D markers 6 can be imaged both in the coordinate system of the data supplied by the 3-D scanner 5 as well as in the coordinate system of the patient data set. Additional 3-D markers 8 which are either attached directly on a bone segment 9 or on a work tool 15 or coupled to these through a kinematic measurement mechanism or a coordinate measurement device, can subsequently be imaged in the patient data set on the display and processing unit 2 . In this way, a spatial displacement of a bone segment 9 that has been simulated on the planning unit 3 , can also be reproduced on the patient. Instead of coupling the 3-D scanner 5 and the 3-D marker position detection unit 4 through a fixed connection, the 3-D scanner 5 can also be flexibly coupled to the position detection unit 4 so as to be movable relative to the 3-D marker position detection unit 4 , and can itself be provided with 3-D markers 8 for detection by the 3-D marker position detection unit 4 . FIG. 6 shows a 3-D marker 16 embodied as an LED and embodied as a passive reflector 17 . The 3-D geometry of the bodies is sufficiently known and can therefore be used directly to uniquely determine the coordinates of the markers from the scanner data, without the need for additional encoding. The markers can be directly used as device geometries. FIG. 7 shows an embodiment of a scanner 18 with a kinematic coordinate measurement device implemented as a measuring profile 19 and directly connected with the position detection unit. If necessary, the relative position of the scanner 18 can be determined by the second kinematic coordinate measurement device with significantly higher accuracy and measuring frequency. In an alternate embodiment, the base of the kinematic coordinate measurement device itself can be provided with a position reference body 20 . In the simplest case, the kinematic coordinate measurement device is a simple body (for example a rod) of known geometry. Advantageously, the kinematic coordinate measurement device can also be attached to a table or applied directly on the patient, depending of which relative accuracy between the markers and the body should be optimized. FIG. 8 shows instead of a bone (hard tissue) a more typical situation involving tissue that does not necessarily have a stable form, and/or an arbitrary body 21 . In the simplest case, a relationship is established via a center of a gravity 22 of the body or another reference volume 23 . This is advantageous when the method is to be applied also to soft tissue, organs or implants during alignment, transplantation and implementation. Even if perfect dimensional stability is not achieved, the method and device can still assist with navigation. Elementary bodies 24 are arranged on the position reference body 20 b. FIG. 9 shows a device for affixing the position reference bodies 20 b to bodies 21 that may lack dimensional stability. The position reference body 20 b is hereby attached to a mechanism that is disposed on the body 21 that lacks dimensional stability. In the depicted example, body tissue is drawn in by a reduced pressure process through a lumen 25 and through a membrane 26 and pressed into a predefined form. This form can advantageously have a shape that facilitates, for example, placement during transplantation or implantation. Other methods for affixing the tissue to the device, for example with adhesive, burrs or stitches, are also feasible.
The invention relates to a method and device for referencing between a data set, which describes geometrically the spatial model of a body, and the real physical environment in which the body is placed. A three-dimensional position reference body is used on the real body. The position reference body has one or more elementary bodies or markers whose 3-dimensional position can be detected with sensors and which define a fixed geometric reference with respect to the center of gravity of the body or to other body reference volumes. For registration, the position reference body and/or its elementary bodies are correlated in the data model and in the physical world.
Briefly summarize the invention's components and working principles as described in the document.
[ "BACKGROUND OF THE INVENTION A patient data set and an operating site during surgery are typically referenced to each other by using either anatomical indicia or—before an image data set is created—implants (bone or skin markers) that are applied to the patient.", "The implants are indicated simultaneously with an input device at a workstation and with a localization system on the patient.", "A more general task relates to referencing between a data set (which describes geometrically the spatial model of a body) and the real physical environment in which the actual body is placed.", "For referencing, a three-dimensional position reference body is used on or applied to the real body.", "The position reference body consists of one or more elementary bodies (markers) whose 3-dimensional position can be detected with sensors and which define a fixed geometric reference with respect to the center of gravity of the body or to other reference volumes of the body.", "For the purpose of registration, the position reference body and/or its elementary bodies are correlated in the data model and in the physical world.", "Unlike the present method, the German patent DE 197 47 427 describes a method and a device wherein the characteristic surface of bone structures is used for providing a reference between a data set and the operating site.", "DE 197 47 427 describes an individual template which carries 3-D localization markers and is applied to and/or screwed on a bone segment.", "The method has the disadvantage that an expensive CAD-CAM model has to be produced from a patient data set before an individual template can be manufactured.", "With many surgical procedures, large areas of bone have to be exposed for applying the individual surface template, which makes the procedure unnecessarily invasive.", "SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and a device for instrument, bone segment, tissue and organ navigation, which operates without auxiliary devices, such as templates, and facilitates a safe and reproducible navigation.", "By using optical measurements and by referencing the operating site via the characteristic surface of a soft tissue envelope or a bone surface, the cost can be reduced significantly and the surgical access path can be significantly less invasive.", "For a bone segment navigation with the present invention, the 3-D localization markers can be individually secured on a bone segment independent of a template—such as a screw, which opens additional possibilities for a minimally-invasive surgical procedure.", "Optical referencing between the data set, the operating site and the 3-D localization markers is also faster and more precise than the aforedescribed referencing method that uses anatomical indicia and implants, because large surface structures in a patient data set (for example MRT or CT) can be imaged more exactly and reproduced than small, singular reference points.", "BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention are illustrated in the drawings and will be described hereinafter in more detail.", "It is shown in FIG. 1 a schematic diagram of the devices in an operating room, FIG. 2 a detailed view of the 3-D reference markers with a device for detecting these markers by optical methods using 3-D scanners, FIG. 3 a geometric device for optical detection of 3-D reference markers, which are affixed to a frame, FIG. 4 a perspective view of the 3-D reference markers with associated geometric devices of different form (depression/sulcus, raised portion/crista, planar color-coded surface) for optical detection with the 3-D scanner, FIG. 5 alternative examples of different geometric forms that have a known spatial association with the 3-D marker, FIG. 6 additional coupled referencing markers, FIG. 7 an embodiment with a different coupling between the scanner and position detection unit, FIG. 8 referencing of bodies that do not necessarily have a stable form, and FIG. 9 device for positioning bodies that do not necessarily have a stable form.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will be described hereinafter in more detail with reference to a first embodiment.", "The entire system 1 is used for optical referencing between an operating site, a patient data set and 3-D markers.", "An optical 3-D scanner 5 is attached to a position detection unit 4 via a coupling device 13 .", "The position detection unit 4 can acquire, for example, infrared signals, ultrasound signals or electromagnetic signals and allows the determination of three-dimensional coordinates of a corresponding 3-D marker 6 (for example: ultrasound transmitter, infrared transmitter, electromagnetic transmitter and/or reflectors 17 for all types of waves, ultrasound, infrared, radar, etc.).", "The 3-D scanner 5 (for example a 3-D laser scanner 5 or a radar unit 5 a ) can detect the shape and color of surfaces (for example 7 ), but not the signals from the 3-D markers 6 .", "The signals from the 3-D markers 6 can be transmitted actively, for example with an LED, or passively, for example by using reflectors.", "The data measured by the position detection unit 4 and the 3-D scanner 5 or the radar unit 5 a are transmitted via a connection 10 and 11 to a display and processing unit 2 .", "Since the position detection unit 4 and the 3-D scanner 5 are coupled via a connection 13 having a known geometrical relationship and/or are kinematically attached to each other via a connection 13 , all coordinates measured with the position detection unit 4 can also be expressed in the coordinate system of the 3-D scanner 5 and vice versa.", "A planning unit 3 is connected via 12 to the display and processing unit 2 .", "Surgical procedures can be simulated on this planning unit 3 ;", "for example, resetting osteotomies can be planned before a bone segment navigation.", "In this embodiment, at least three 3-D markers 6 are attached to the patient, which define a coordinate system on the patient.", "Geometric FIGS. 7 which can be detetced by the 3-D scanner 5 , are arranged in a known, fixed spatial relationship to these 3-D markers 6 .", "These FIGS. 7 can be implemented, for example, as a depression/sulcus 7 a, a raised portion/crista 7 b, as color-coded lines and fields 7 c or as a bar code.", "The geometric FIG. 7 can also be in the form of a base on which a 3-D marker 6 is placed.", "The geometric FIG. 7 can also be formed directly by one or several 3-D markers 6 .", "The coordinates of the 3-D markers 6 can be uniquely determined by processing unit 2 from the geometry of the devices 7 by an inverse transformation.", "The geometry of these devices 7 can be different ( 7 ′, 7 ″, 7 ′″);", "it is only necessary that the geometry can be detected by the 3-D scanner 5 and that the processing unit 2 can determine the coordinates of the 3-D markers 6 from the geometry of the devices 7 .", "If the three 3-D markers 6 are fixedly connected with one another by a frame 14 in order to define a patient coordinate system, then the coordinates of the 3-D markers 6 can be determined by the processing unit 2 from the arrangement of the geometric FIGS. 7 on the frame 14 .", "Alternatively, the scanner can also determine the coordinates directly by the analyzing the known geometries of the 3-D markers.", "The operating site, the patient data set and the 3-D markers 6 are referenced to each other by first detecting with the 3-D scanner 5 the soft tissue (before the surgery, i.e., before the soft tissue swells or is displaced) or the bone surfaces 9 of the patient.", "The processing unit 2 processes the data from the 3-D scanner 5 and determines the most advantageous surface area fit between the patient and the patient data set.", "Thereafter, the patient and the patient data set can be referenced to each other by a coordinate transformation.", "So far, however, the 3-D scanner 5 has not yet detected the 3-D markers 6 .", "However, since the geometric devices 7 surrounding the 3-D markers 6 were scanned together with the patient and since the spatial relationship between the 3-D markers 6 and the geometric devices 7 is known, the coordinates of the 3-D markers 6 can be imaged both in the coordinate system of the data supplied by the 3-D scanner 5 as well as in the coordinate system of the patient data set.", "Additional 3-D markers 8 which are either attached directly on a bone segment 9 or on a work tool 15 or coupled to these through a kinematic measurement mechanism or a coordinate measurement device, can subsequently be imaged in the patient data set on the display and processing unit 2 .", "In this way, a spatial displacement of a bone segment 9 that has been simulated on the planning unit 3 , can also be reproduced on the patient.", "Instead of coupling the 3-D scanner 5 and the 3-D marker position detection unit 4 through a fixed connection, the 3-D scanner 5 can also be flexibly coupled to the position detection unit 4 so as to be movable relative to the 3-D marker position detection unit 4 , and can itself be provided with 3-D markers 8 for detection by the 3-D marker position detection unit 4 .", "FIG. 6 shows a 3-D marker 16 embodied as an LED and embodied as a passive reflector 17 .", "The 3-D geometry of the bodies is sufficiently known and can therefore be used directly to uniquely determine the coordinates of the markers from the scanner data, without the need for additional encoding.", "The markers can be directly used as device geometries.", "FIG. 7 shows an embodiment of a scanner 18 with a kinematic coordinate measurement device implemented as a measuring profile 19 and directly connected with the position detection unit.", "If necessary, the relative position of the scanner 18 can be determined by the second kinematic coordinate measurement device with significantly higher accuracy and measuring frequency.", "In an alternate embodiment, the base of the kinematic coordinate measurement device itself can be provided with a position reference body 20 .", "In the simplest case, the kinematic coordinate measurement device is a simple body (for example a rod) of known geometry.", "Advantageously, the kinematic coordinate measurement device can also be attached to a table or applied directly on the patient, depending of which relative accuracy between the markers and the body should be optimized.", "FIG. 8 shows instead of a bone (hard tissue) a more typical situation involving tissue that does not necessarily have a stable form, and/or an arbitrary body 21 .", "In the simplest case, a relationship is established via a center of a gravity 22 of the body or another reference volume 23 .", "This is advantageous when the method is to be applied also to soft tissue, organs or implants during alignment, transplantation and implementation.", "Even if perfect dimensional stability is not achieved, the method and device can still assist with navigation.", "Elementary bodies 24 are arranged on the position reference body 20 b. FIG. 9 shows a device for affixing the position reference bodies 20 b to bodies 21 that may lack dimensional stability.", "The position reference body 20 b is hereby attached to a mechanism that is disposed on the body 21 that lacks dimensional stability.", "In the depicted example, body tissue is drawn in by a reduced pressure process through a lumen 25 and through a membrane 26 and pressed into a predefined form.", "This form can advantageously have a shape that facilitates, for example, placement during transplantation or implantation.", "Other methods for affixing the tissue to the device, for example with adhesive, burrs or stitches, are also feasible." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a National Stage of International Application No. PCT/CN2015/076273, filed Apr. 10, 2015 and published in Chinese as WO 2015/154716 on Oct. 15, 2015. This application claims priority to Chinese Application No. 201410142608.8, filed on Apr. 10, 2014. The entire disclosures of the above applications are incorporated herein by reference. FIELD OF INVENTION [0002] The present invention relates to pharmaceutical field, specially a novel phenanthroline phosphonic acid compound and a pharmaceutical salt thereof, preparation of the compound, as well as an application of the compound and the pharmaceutical salt thereof as collagen prolyl-4-hydroxylase inhibitors in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease. BACKGROUND [0003] The following description of the background of the invention is provided to aid in understanding the invention, but is not admitted to be, or to describe, prior art to the invention. All cited publications are incorporated by reference in their entirety. [0004] The foundation of hepatic fibrosis is that excess collagen (especially collagen I) is synthesized ( Clin. Sci. 1997, 92, 103) by liver which deposits on extracellular matrix (EXM). The biosynthesis of collagen includes series of post-translational modification of procollagen. Five enzymes, 3 collagen hydroxylases and 2 collagen glycosyltransferases, are involved in this process. Among these hydroxylases, prolyl-4-hydroxylase (P4H) is a tetramer of 2 α subunits (P4Hα1, P4Hα2) and 2 β subunits. β Subunit is disulfide isomerase, and the main parts having catalytic effect locate in β Subunit, and the major role of α subunit is deciding the activity of the enzyme. Prolyl-4-hydroxylase is the rate limiting enzyme in the synthesis of 21 different collagen ( Critical Reviews in Biochemistry and Molecular Biology 2010, 45, 106). P4H locates in the endoplasmic reticulum, and catalyzes the formation of 4-hydroxyproline, from the proline residue on X-Pro-Gly sequence, in the presence of Fe 2+ , O 2 , 2-oxoglutarate and ascorbate. [0005] P4H hydroxylate proline to 4-hydorxyproline (4-HYP) in certain positions of the procollagen, thus enhances the stability of collagen by forming triple helixes under physiological circumstances. Conversely, with less 4-HYP content, the collagen is unable to form stable triple helixes structure and degrades ( Matrix Biol. 2003, 22, 15). Therefore, inhibition of P4H activity is widely accepted as a valid method for controlling excess collagen synthesis (fibrosis). ( Hepatol. 1998, 28, 404). Several small molecule P4H inhibitors were verified to be effective in preventing collagen synthesis in vitro and in vivo ( J. Hepatol. 1997, 27, 185 ; Hepatol. 1996, 23, 755 ; Hepatol. 1998, 28, 404 ; Biochem. J. 1994, 300, 525 ; J. Hepatol. 1991, 13, S35). For example, P4H inhibitor HOE077 inhibits expression of procollagen mRNA and reduces hepatic stellate cells proliferation ( Hepatol. Res. 2002, 23, 1 ; J. Hepatol. 1997, 27, 185), also inhibits activation of hepatic stellate cells ( Hepatol. 1996, 23, 755). The inhibitory effect of HOE077 on procollagen gene and protein was dose-dependent, but no effect on the synthesis of total protein of cell was observed. The inhibitory effect of HOE077 is possibly due to the inhibition of the expression of TIMP gene to expedite collagen degradation process ( J. Gastroenterol. 1999, 34, 376). Several P4H inhibitors showed anti-fibrotic effects in various animal liver fibrosis models (CO 4 , TAA etc.). ( Hepatol. 1998, 28, 404 ; Hepatol. 1996, 23, 755 ; J. Hepatol. 1997, 27, 185). Another P4H inhibitor FG-041 (1,4-dihydrophenanthrol-4-one-3-carboxylic acid) was reported to prevent myocardial infarction in animal experiment ( Circulation 2001, 104, 2216). P4H inhibitors were also reported to prevent bladder block ( Urology 2012, 80, 1390). [0006] P4H exists everywhere in body. Thus, P4H inhibitors is targeted-delivered to diseased organ while the other normal organ don't be influenced, is the key to successful development of safe and effective P4H inhibitors. In 1990s, HOECHST (which is france sanofi now) firstly developed HOE077 to treat liver cirrhosis ( Hepatol. 1996, 23, 755 ; J. Hepatol. 1997, 27, 185). Preclinical experiments showed promising results though severe side effects (cataract) were observed in clinical trials. It is reported that inhibition of collagen synthesis could seriously influence the function of organ, such as eyes and kidneys ( J. Biol. Chem. 2010, 285, 42023). Collagen synthesis widely exists in cellular matrix, therefore, the suppression of collagen synthesis of organ cell matrix results in the effusion of macromolecules, which cause the change of the organ function. Thus, the key to developing the P4H inhibitors used to treat organ fibrosis (such as liver fibrosis) is how to deliver the P4H inhibitors to specified organ. Prodrugs have been widely used in targeted therapeutic areas ( J. Pharmacol. Exp. Ther. 2005, 312, 554). 1,3-Propane diols could form cyclic phosphonate esters with phosphonic acids, which were reported liver targeting ( J. Med. Chem. 2008, 51, 666). The liver prodrug-delivery which the present invention adopts is to modify the active component of the drug to inactive prodrug. The prodrug may only be metabolized under the catalysis of liver-specific enzymes, for example, cytochrome P450, to release the active component in liver, therefor the active component produce effect in liver. Content of the Present Invention [0007] The purpose of the present invention is to provide a novel phenantholine phosphonic acid compound and the pharmaceutical salt thereof. The another purpose of the present invention is to provide a preparation of the compound and the pharmaceutical salt thereof. The another purpose of the present invention is to provide an application of the compound and the pharmaceutical salt thereof as collagen prolyl-4-hydroxylase inhibitors in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease. [0008] In one aspect, the present invention provides compounds of Formula I or Formula II, and pharmaceutically acceptable salts thereof: [0000] [0009] Wherein, in Formula I: [0010] X is —Cl or —OR 3 ; R 3 is —H, —C(O)—(C 1 -C 6 alkyl), —PO(OH) 2 or —CH 2 OPO(OH) 2 ; [0011] Each of R 1 and R 2 can be independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and CH 2 OCOO—(C 1 -C 6 alkyl); or R 1 and R 2 join to form a group having the formula: [0000] [0012] Wherein Y is aryl or heteroaryl; [0013] In one aspect, X could be selected from —Cl, and —OR 3 , R 3 is —H, —C(O)—(C 1 -C 6 alkyl), —PO(OH) 2 or —CH 2 OPO(OH) 2 ; [0014] In another aspect, each of R 1 and R 2 could be independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and —CH 2 OCOO—(C 1 -C 6 alkyl); or R 1 and R 2 join to form a group having the formula: [0000] [0015] Wherein Y is aryl, heteroaryl; [0016] Wherein, in Formula II: [0017] Z is —H or —CH 2 OPO(OH) 2 ; each of R 1 and R 2 is independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and —CH 2 OCOO—(C 1 -C 6 alkyl); or R 1 and R 2 join to form a group having the formula: [0000] [0018] Wherein Y is aryl or heteroaryl. [0019] In one aspect, Z could be selected from —H, and CH 2 OPO(OH) 2 ; [0020] In another aspect, each of R 1 and R 2 can be independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and —CH 2 OCOO—(C 1 -C 6 alkyl); or R 1 and R 2 join to form a group having the formula: [0000] [0021] Wherein Y is aryl, heteroaryl. [0022] In a preferred embodiment, the compound have the following formula: [0000] [0023] In another preferred embodiment, the compound have the following formula: [0000] [0024] In another preferred embodiment, the compound have the following formula: [0000] [0025] In the second aspect, the present invention provides the method of preparing the phenantholine phosphonic acid compound and the pharmaceutical salt thereof. [0026] In the third aspect, the present invention provides an application of the phenantholine phosphonic acid compound and the pharmaceutical salt thereof as collagen prolyl-4-hydroxylase inhibitors in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease. [0027] The present invention provides an application of the compounds of Formula I or Formula II or the pharmaceutical salt thereof in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease. [0028] The present invention provides an application of the compounds of Formula I or Formula II, or the in vivo metabolite thereof, or the pharmaceutical salt thereof used as collagen prolyl-4-hydroxylase inhibitors. [0029] The present invention could protect liver function by administering to a patient with chronic liver injuries a therapeutically effective amount of the compound of Formula I and Formula II, or pharmaceutically acceptable salts thereof. [0030] The present invention could prevent and treat liver fibrosis by administering to a patient with chronic liver injuries a therapeutically effective amount of the compound of Formula I and Formula II, or pharmaceutically acceptable salts thereof. [0031] The present invention could prevent liver fibrosis by administering to a patient at risk for developing diabetes a therapeutically effective amount of the compound of Formula I and Formula II, or pharmaceutically acceptable salts thereof. DESCRIPTION OF FIGURES [0032] FIG. 1 . The IC50 of Compound 9c against P4H enzyme [0033] FIG. 2 . Concentration-time curve of compound 16c in plasma after iv dosing 16c (3 mg/kg) and PO dosing 27 (39 mg/kg). [0034] FIG. 3 . H&E staining of rat liver (SHAM group) [0035] FIG. 4 . H&E staining of rat liver (BDL 2 weeks) [0036] FIG. 5 . H&E staining of rat liver (BDL, PO administration of 27, 30 mpk, 2 weeks) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Definitions of Terms [0037] In accordance with the present invention and as used herein, the following terms are defined with the following meanings, unless explicitly stated otherwise. [0038] The term “alkyl” refers to saturated aliphatic groups including straight-chain, branched chain and cyclic groups, up to and including 20 carbon atoms. Suitable alkyl groups include methyl, ethyl, n-propyl, isopropyl, and cyclopropyl. The alkyl may be optionally substituted with 1-3 substituents. [0039] The term “aryl” refers to aromatic groups which have 5-14 ring atoms and at least one ring having a conjugated pi electron system and includes carbocyclic aryl, heterocyclic aryl, fused aryl and biaryl aryl, all of which may be optionally substituted. The aryl may be optionally substituted with 1-6 substituents. [0040] Heterocyclic aryl or heteroaryl groups are groups which have 5-14 ring atoms wherein 1 to 4 heteroatoms are ring atoms in the aromatic ring and the remainder of the ring atoms being carbon atoms. Suitable heteroatoms include oxygen, sulfur, nitrogen, and selenium. Suitable heteroarylgroups include furanyl, thienyl, pyridyl, pyrrolyl, N-lower alkyl pyrrolyl, pyridyl-N-oxide, pyrimidyl, pyrazinyl, imidazolyl, and the like, all optionally substituted. [0041] The term “optionally substituted” or “substituted” refers to the groups substituted by one to four substituents, independently selected from lower alkyl, lower aryl, lower aralkyl, lower cyclic alkyl, lower heterocycloalkyl, hydroxy, lower alkoxy, lower aryloxy, perhaloalkoxy, aralkoxy, lower heteroaryl, lower heteroaryloxy, lower heteroarylalkyl, lower heteroaralkoxy, azido, amino, halo, lower alkylthio, oxo, lower acylalkyl, lower carboxy esters, carboxyl, carboxamido, nitro, lower acyloxy, lower aminoalkyl, lower alkylaminoaryl, lower alkylaryl, lower alkylaminoalkyl, lower alkoxyaryl, lower arylamino, lower aralkylamino, sulfonyl, lower carboxamidoalkylaryl, lower carboxamidoaryl, lower hydroxyalkyl, lower haloalkyl, lower alkylaminoalkylcarboxy, lower aminocarboxamidoalkyl, cyano, lower alkoxyalkyl, lower perhaloalkyl, and lower arylalkyloxyalkyl. [0042] “Substituted aryl” and “substituted heteroaryl” refers to aryl and heteroarylgroups substituted with 1-6 substituents. These substituents are selected from lower alkyl, lower alkoxy, lower perhaloalkyl, halo, hydroxy, and amino. [0043] The term “halogen” or “halo” refers to —F, —Cl, —Br and —I. [0044] The phrase “therapeutically effective amount” means an amount of the compound or a combination of compounds needed to ameliorates, attenuates, eliminates or prevents, modifies, delays one or more of the symptoms of a particular disease The term “pharmaceutically acceptable salt” refers to the salts generated by mixing the compounds of Formula I or Formula II and the prodrug thereof with an organic or inorganic acid or base. Suitable acids include acetic acid, adipic acid, benzenesulfonic acid, (+)-7,7-dimethyl-2-oxobicyclo[2.2.1]heptane-1-methanesulfonic acid, citric acid, 1,2-ethanedisulfonic acid, dodecyl sulfonic acid, fumaric acid, glucoheptonic acid, gluconic acid, glucuronic acid, hippuric acid, hydrochloride hemiethanolic acid, HBr, HCl, HI, 2-hydroxyethanesulfonic acid, lactic acid, lactobionic acid, maleic acid, methanesulfonic acid, methylbromide acid, methyl sulfuric acid, 2-naphthalenesulfonic acid, nitric acid, oleic acid, 4,4′-methylenebis [3-hydroxy-2-naphthalenecarboxylic acid], phosphoric acid, polygalacturonic acid, stearic acid, succinic acid, sulfuric acid, sulfosalicylic acid, tannic acid, tartaric acid, terphthalic acid, and p-toluenesulfonic acid. The salt generated by mixing with suitable base is sodium salt, potassium salt, calcium salt, magnesium salt, lithium salt, cesium salt, amino acid salt. [0045] The term “patient” refers to a male or female mammal animal being treated, such as a dog, a cat, a cow, a horse, a sheep, and a human. [0046] The term “prodrug” as used herein refers to any compound that when administered to a biological system generates a biologically active compound as a result of spontaneous chemical reaction(s), enzyme catalyzed chemical reaction(s), and/or metabolic chemical reaction(s), or a combination of each. Standard prodrugs are formed using groups attached to functionality, e.g. HO—, HS—, HOOC—, R 2 N—, associated with the drug, that cleave in vivo. Standard prodrugs include but are not limited to carboxylate esters where the group is alkyl, aryl, aralkyl, acyloxyalkyl, alkoxycarbonyloxyalkyl, as well as acyl, alkoxycarbonyl, aminocarbonyl, phosphate or sulfate which attached to hydroxyl, thiol and amines. The groups illustrated are exemplary, not exhaustive, and one skilled in the art could prepare other known varieties of prodrugs. Such prodrugs of the compounds of Formula I and II fall within this scope. Prodrugs must undergo some form of a chemical transformation to produce the compound that is biologically active or is a precursor of the biologically active compound. In some cases, the prodrug is biologically active, usually less than the drug itself, and serves to improve drug efficacy or safety through improved oral bioavailability, pharmacodynamic half-life, etc. Prodrug forms of compounds may be utilized, for example, to improve bioavailability, improve subject acceptability by masking or reducing unpleasant characteristics such as bitter taste or gastrointestinal irritability, alter solubility for intravenous use, provide for prolonged or sustained release or delivery, improve ease of formulation, or provide site-specific delivery of the compound. Prodrugs are described in The Organic Chemistry of Drug Design and Drug Action, by Richard B. Silverman, Academic Press, San Diego, 1992. Chapter 8: “Prodrugs and Drug delivery Systems” pp. 352-401; Design of Prodrugs, edited by H. Bundgaard, Elsevier Science, Amsterdam, 1985; Design of Biopharmaceutical Properties through Prodrugs and Analogs, Ed. by E. B. Roche, American Pharmaceutical Association, Washington, 1977; and Drug Delivery Systems, ed. by R. L. Juliano, Oxford Univ. Press, Oxford, 1980. [0047] The term “percent enantiomeric excess (% ee)” refers to optical purity. It is obtained by the following formula: [0000] [ R ] - [ S ] [ R ] + [ S ] × 100 = %   R -  %   S [0048] wherein [R] represents the amount of the R isomer, and [S] represents the amount of the S isomer. This formula provides the % ee when R is the dominant isomer. [0049] The terms “treating” or “treatment” a disease, includes preventing the disease from occurring (prophylactic treatment), inhibiting the disease (slowing or arresting its development), providing relief from the symptoms or side-effects of the disease (including palliative treatment), and relieving the disease (causing regression of the disease). [0050] The formulations of the compound of the present patent: [0051] Compounds of the invention are administered in a total daily dose of 0.01 to 2500 mg. In one aspect, the range is about 5 mg to about 500 mg. The dose may be administered in as many divided doses as is convenient. [0052] Compounds of this invention when used in combination with other agents may be administered as a daily dose or an appropriate fraction of the daily dose (e.g., bid). The compounds of this invention may be used as a part of a multidrug regimen, also known as combination or ‘cocktail’ therapy, wherein, multiple agents may be administered together, may be administered separately at the same time or at different intervals, or administered sequentially. The compounds of this invention may be administered after a course of treatment by another agent, during a course of therapy with another agent, administered as part of a therapeutic regimen, or may be administered prior to therapy by another agent in a treatment program. [0053] For achieving the purpose of treatment, the compounds of this invention may be administered by a variety of means including orally, parenterally, by inhalation spray, topically, or rectally in formulations containing pharmaceutically acceptable carriers, adjuvants and vehicles. The term parenteral as used here includes subcutaneous, intravenous, intramuscular, and intraarterial injections with a variety of infusion techniques. Intraarterial and intravenous injection as used herein includes administration through catheters. Intravenous administration is generally preferred. Pharmaceutically acceptable salts include sodium salt, potassium salt, calcium salt, magnesium salt, lithium salt, cesium salt, amino acid salt, acetate, adipate, besylate, bromide, camsylate, hydrochloride, citrate, edisylate, estolate, fumarate, gluceptate, gluconate, glucoranate, hippurate, hyclate, bromide, chloride, iodide, isethionate, lactate, lactobionate, maleate, mesylate, methylbromide, methylsulfate, napsylate, nitrate, oleate, palmoate, phosphate, polygalacturonate, stearate, succinate, sulfate, sulfo salicylate, tannate, tartrate, terphthalate, tosylate, and triethiodide. [0054] The active ingredient of drug have different forms for different method of administration. For example, when used for oral use, tablets, troches, lozenges, aqueous or oil suspensions, dispersible powders or granules, emulsions, hard or soft capsules, syrups or elixirs may be prepared. The method of preparing oral preparation could refer to the manufacturing process of known medicine. In order to provide a palatable preparation, the preparation may contain one or more agents including sweetening agents, flavoring agents, coloring agents and preserving agents. Tablets containing the active ingredient in admixture with non-toxic pharmaceutically acceptable excipient which are suitable for manufacture of tablets are acceptable. These excipients may be, for example, inert diluents, such as calcium or sodium carbonate, lactose, calcium or sodium phosphate; granulating and disintegrating agents, such as maize starch, or alginic acid; binding agents, such as starch, gelatin or acacia; and lubricating agents, such as magnesium stearate, stearic acid or talc. Tablets may be uncoated or may be coated by known techniques including microencapsulation to delay disintegration and adsorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate alone or with a wax may be employed. [0055] Formulations for oral use may be in the form of hard gelatin capsules in which the active ingredient is mixed with an inert solid diluent, for example calcium phosphate or kaolin, or as soft gelatin capsules in which the active ingredient is mixed with water or an oil medium, such as peanut oil, liquid paraffin or olive oil. [0056] The active ingredients of the invention may be also mixed with excipients suitable for industrial manufacture to produce aqueous suspensions. Such excipients include suspending agent, such as sodium carboxymethylcellulose, methylcellulose, ethylcellulose, hydroxypropylcellulose, hydroxypropyl methylcellulose, sodium alginate, polyvinylpyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents, such as a natural phosphatide (e.g., lecithin), condensation products of alkylene oxides with fatty acids (e.g., polyoxyethylene stearate), condensation products of ethylene oxides with long chain aliphatic alcohols (e.g., heptadecyl ethyleneoxy ethanol), condensation products of ethylene oxide with a partial ester derived from fatty acids and hexitol anhydrides (e.g., polyoxyethylene sorbitan monooleate). The aqueous suspension may also contain one or more preservatives such as ethyl or n-propyl p-hydroxy-benzoate, coloring agents, flavoring agents and sweetening agents, such as sucrose and saccharin. [0057] Oil suspensions may be formulated by suspending the active ingredient in a vegetable oil (such as arachis oil, olive oil, sesame oil or coconut oil), or in a mineral oil (such as liquid paraffin). The oral suspensions may also contain a thickening agent (such as beeswax, hard paraffin or cetyl alcohol). Sweetening agents such as those set forth above, and flavoring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an antioxidant such as ascorbic acid. Dispersible powders and granules of the invention is suitable for preparation of an aqueous suspension by the addition of water generally contain the the active ingredient together with a dispersing or wetting agent, suspending agent, and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those disclosed above. Additional excipients, for example sweetening, flavoring and coloring agents, may also be present. [0058] The pharmaceutical compositions of the invention may also be in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, such as olive oil and arachis oil, a mineral oil, such as liquid paraffin, or a mixture of these. Suitable emulsifying agents include naturally-occurring gums, such as gum acacia and gum tragacanth, naturally-occurring phosphatides, such as soybean lecithin, esters or partial esters derived from fatty acids and hexitol anhydrides, such as sorbitan monooleate, and condensation products of these partial esters with ethylene oxide, such as polyoxyethylene sorbitan monooleate. The emulsion may also contain sweetening and flavoring agents. [0059] Syrups and elixirs may be formulated with sweetening agents, such as glycerol, sorbitol or sucrose. Such formulations may also contain a demulcent, preservative, flavoring or coloring agent. [0060] The pharmaceutical compositions of the invention may be in the form of a sterile injectable preparation, such as a sterile injectable aqueous or oleaginous suspension. This suspension may be formulated according to the known art using those suitable dispersing or wetting agents and suspending agents which have been mentioned above. The sterile injectable preparation may also be a solution or suspension which is prepared by non-toxic injectable diluent or solvent, such as preparing lyophilized powder and dissolving in 1,3-butane-diol. The acceptable vehicles and solvents may be water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile fixed oils may conventionally be employed as a solvent or suspending medium. Any bland fixed oil may be employed including synthetic mono- or di-glycerides. In addition, fatty acids such as oleic acid may likewise be used in the injectable preparation. [0061] The amount of active ingredient that may be combined with the carrier material to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. For example, a time-release formulation intended for oral administration to humans may contain 20 to 2000 μmol (approximately 10 to 1000 mg) active ingredient and appropriate carrier material which may vary from about 5 to about 95% of the total compositions. It is preferred that the pharmaceutical composition be prepared which provides easily measurable amounts for administration. For example, an aqueous solution intended for intravenous infusion should contain from about 0.05 to about 50 μmol (approximately 0.025 to 25 mg) of the active ingredient per milliliter of solution in order that infusion of a suitable volume at a rate of about 30 mL/hr can occur. [0062] As noted above, oral preparation may be presented as discrete units such as capsules, cachets or tablets, each containing a predetermined amount of the active ingredient; as a powder or granules; as a solution or suspension in an aqueous or non-aqueous liquid; or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion. The active ingredient may also be administered as a bolus, electuary or paste. [0063] A tablet may be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing in a suitable machine the active ingredient in a free flowing form such as a powder or granules, optionally mixed with a binder (e.g., povidone, gelatin, hydroxypropylmethyl cellulose), lubricant, inert diluent, preservative, disintegrant (e.g., sodium starch glycolate, cross-linked povidone, cross-linked sodium carboxymethyl cellulose) surface active or dispersing agent. Molded tablets may be made by molding in a suitable machine a mixture of the powdered compound moistened with an inert liquid diluent. The tablets may optionally be coated or scored in preparing so as to provide slow or controlled release of the active ingredient therein using, for example, hydroxypropyl methylcellulose in varying proportions to provide the desired release profile. Tablets may optionally be provided with an enteric coating, to provide release in parts of the gut other than the stomach. This is particularly advantageous with the compounds of Formula I when such compounds are susceptible to acid hydrolysis. [0064] Formulations suitable for topical administration in the mouth include pastille comprising the active ingredient in a flavored base, usually sucrose, acacia or tragacanth; pastilles comprising the active ingredient in an inert base such as gelatin, glycerin, sucrose and acacia; and mouthwashes comprising the active ingredient in a suitable liquid carrier. [0065] Formulations for rectal administration may be presented as a suppository comprising the active compound in a suitable base comprising such as cocoa, butter or a salicylate. Formulations suitable for vaginal administration may add the active ingredient and known suitable carriers in pessaries, tampons, creams, gels, pastes, foams or spray. [0066] Formulations suitable for parenteral administration include aqueous and non-aqueous isotonic sterile injection solutions which may contain antioxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose sealed containers, for example, ampoules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. [0067] Injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the kind previously described. [0068] Formulations suitable for parenteral administration may be administered in a continuous infusion manner via an indwelling pump or via a hospital bag. The infusions may be done through a Hickman or PICC or any other means suitable for parenterally and i.v. [0069] Preferred unit dosage formulations contains a daily dose or unit, each dose, and daily frequency. [0070] It will be understood, however, that the specific dose level for any particular patient will depend on a variety of factors including the activity of the specific compound employed; the age, body weight, general health, sex and diet of the individual being treated; the time and route of administration; the rate of excretion; other drugs which have previously been administered; and the severity of the particular disease undergoing therapy, as is well understood by those skilled in the art. Synthesis of the Compounds of Formula I and Formula II [0071] The compounds in this invention may be prepared by the processes described in the following discussions, as well as relevant published literature procedures that are used by those skilled in the art. It should be understood that the following discussions are provided solely for the purpose of illustration and do not limit the invention which is defined by the claims. Typically the synthesis of the compound of Formula I includes the following general five steps (listed in reversed order): (1) Preparation of a prodrug; (2) Deprotection of a phosphonate ester; (3) Modifications of an existing quinoline; (4) Construction of a quinoline; and (5) Preparation of key precursors. The compounds of Formula II could be synthesized by the compounds of Formula I reacting with suitable groups. Protection and deprotection in the Schemes may be carried out according to the procedures generally known in the art (e.g., “Protecting Groups in Organic Synthesis,” 3rd Edition, Wiley, 1999). [0072] All stereoisomers of the compounds of the present invention are contemplated, either in admixture or in pure or substantially pure form. The compounds of the present invention can have stereogenic centers at the phosphorus atom and at any of the carbons including any of the R substituents. Consequently, compounds of Formula I can exist in enantiomeric or diastereomeric forms or in mixtures thereof. The processes for preparation can utilize racemates, enantiomers or diastereomers as starting materials. When enantiomeric or diastereomeric products are prepared, they can be separated by conventional methods. For example, chromatography or fractional crystallization can be used to separate diastereomeric mixtures, while derivatives of enantiomeric isomers can be separated via chromatography. 1) Preparation of a Prodrug [0073] Prodrugs can be introduced at different stages of the synthesis. Most often these prodrugs are introduced at the later stage of a synthesis due to the lability of various prodrugs, while prodrugs could also be introduced at an early stage of the synthesis due to other considerations. [0074] The compounds of Formula I could be phosphonic acids wherein both R 1 and R 2 are H, and also be in a suitably protected form. Phosphonic acids can be alkylated with electrophiles such as alkyl halides and alkyl sulfonates under nucleophilic substitution conditions to give phosphonate esters. For example, compounds of Formula I wherein Wand R 2 are acyloxyalkyl groups can be prepared by direct alkylation of compounds of Formula I wherein both R 1 and R 2 are H with an appropriate acyloxyalkyl halide (e.g. Cl, Br, I; Phosphorus Sulfur 1990, 54, 143 ; Synthesis 1988, 62) in the presence of a suitable base (e.g. pyridine, TEA, diisopropylethylamine) in suitable solvents such as DMF ( J. Med. Chem. 1994, 37, 1875). The carboxylate component of these acyloxyalkyl halides includes but is not limited to acetate, propionate, isobutyrate, pivalate, benzoate, carbonate and other carboxylates. [0075] Reactive dichlorophosphonates can be generated from the corresponding phosphonic acids with a chlorinating agent (e.g. thionyl chloride, J. Med. Chem. 1994, 1857; oxalyl chloride, Tetrahedron Lett. 1990, 31, 3261; phosphorous pentachloride, Synthesis 1974, 490). Alternatively, a dichlorophosphonate can be generated from its corresponding disilyl phosphonate esters ( Synth. Commu. 1987, 17, 1071) and dialkyl phosphonate esters ( Tetrahedron Lett. 1983, 24, 4405 ; Bull. Soc. Chim. 1993, 130, 485). Cyclic phosphonate esters of substituted 1,3-propane diols can be synthesized by either reactions of the corresponding dichlorophosphonate with a substituted 1,3-propanediol or coupling reactions using suitable coupling reagents (e.g. DCC, EDCI, PyBOP; Synthesis 1988, 62). [0076] Alternatively, these cyclic phosphonate esters of substituted 1,3-propane diols are prepared from phosphonic acids by coupling with diols under Mitsunobu reaction conditions ( Synthesis 1 (1981); J. Org. Chem. 52:6331 (1992)), and other acid coupling reagents including, but not limited to, carbodiimides ( Collect. Czech. Chem. Commun. 59:1853 (1994); Bioorg. Med. Chem. Lett. 2:145 (1992); Tetrahedron Lett. 29:1189 (1988)), and PyBOP ( Tetrahedron Lett. 34, 6743 (1993)). [0077] One aspect of the present invention provides methods to synthesize and isolate single isomers of prodrugs of phosphonic acids of Formula I. Because phosphorus is a stereogenic atom, formation of a prodrug with a racemic substituted-1,3-propane-diol will produce a mixture of isomers. For example, formation of a prodrug with a racemic 1-(Y)-substituted-1,3-propane diol gives a racemic mixture of cis-prodrugs and a racemic mixture of trans-prodrugs. In another aspect, the use of the enantioenriched substituted-1,3-propane diol with the R-configuration gives enantioenriched R-cis- and R-trans-prodrugs. These compounds can be separated by a combination of column chromatography and/or fractional crystallization. [0078] Another prodrug group can be introduced for expected properties. Compounds of Formula I (X=OH) can be connected with different protecting groups on the O atom of N atom of the hydroxypyridine ring. For example, compounds of formula I (R 3 is carboxyl group) could be prepared from compound of formula I (R 3 is H) with appropriate carboxyl halide under suitable reaction conditions ( J. Org. Chem. 1989, 54, 166); compounds of formula I (X is Cl) could be generated from compound of formula I (X is OH) with different chlorinating reagent (for example: POCl 3 , J. Org. Chem. 1950, 15, 1224; CCl 3 CN, Tetrahedron Lett. 2012, 53, 674) under appropriate conditions. 2) Deprotection of a Phosphonate Ester [0079] Compounds of Formula I wherein R 1 is H may be prepared from phosphonate esters using known phosphate and phosphonate ester cleavage conditions. Silyl halides are generally used to cleave various phosphonate esters, and subsequent mild hydrolysis of the resulting silyl phosphonate esters give the desired phosphonic acids. When required, acid scavengers (e.g. 1,1,1,3,3,3-hexamethyldisilazane, 2,6-lutidine) can be used for the synthesis of acid labile compounds. Such silyl halides include chlorotrimethylsilane J. Org. Chem., 1963, 28: 2975), and bromotrimethylsilane ( Tetrahedron Lett., 1977, 155), and iodotrimethylsilane ( J. Chem. Soc., Chem. Commun., 1978, 870). Alternately, phosphonate esters can be cleaved under strong acidic conditions (e.g. HBr or HCl: Moffatt, et al, U.S. Pat. No. 3,524,846, 1970). These esters can also be cleaved via dichlorophosphonates, prepared by treating the esters with halogenating agents (e.g. phosphorus pentachloride, thionyl chloride, BBr 3 : Pelchowicz et al., J. Chem. Soc., 1961, 238) followed by aqueous hydrolysis to give phosphonic acids. Aryl and benzyl phosphonate esters can be cleaved under hydrogenolysis conditions (Lejczak, et al., Synthesis, 1982, 412; Elliott, et al., J. Med. Chem., 1985, 28: 1208; Baddiley, et al., Nature, 1953, 171: 76) or metal reduction conditions (Shafer, et al., J. Am. Chem. Soc., 1977, 99: 5118). Electrochemical (Shono, et al., J. Org. Chem., 1979, 44: 4508) and pyrolysis (Gupta, et al., Synth. Commun., 1980, 10: 299) conditions have also been used to cleave various phosphonate esters. (3) Synthesis of Phosphorus-Containing Phenantholines [0080] Construction of the phenantholine core could be carried out using well-established literature methods. For example, a thermal cyclization strategy is illustrated in the following scheme. [0000] [0081] Treatment of arylamine 1 with sodium 3-nitrobenzenesulfonate, sulfuric acid and glycerol provided quinoline 2. Bromination of quinoline 2 using NBS in acetic acid provided compound 3 which was reduced using iron to give compound 4. Phosphonylation of compound 4 gave phosphonate 5 which was treated with compound 17 and followed by a thermal cyclization reaction to provide phenantholine 7 wherein R is H (compounds of formula I wherein X is OH, R 1 =R 2 =Et). Treatment of compound 7 with sodium hydroxide provided compound 8 wherein R is H (compounds of formula I wherein X is OH, R 1 =H, R 2 =Et); on the other hand, treatment of compound 7 with 48% HBr provided compound 9 wherein R is H (compounds of formula I wherein X is OH, R 1 =R 2 =H). In some cases, the desired substituents are not compatible with subsequent reactions, and therefore modifications of an existing phenantholine are envisioned using conventional chemistry (Larock, Comprehensive organic transformations , VCH, New York, 1989; Trost, Comprehensive organic synthesis ; Pergamon press, New York, 1991). [0082] Prodrugs often are introduced at the later stage of a synthesis, while some prodrugs could also be introduced at an early stage of the synthesis due to other considerations. For example, the cyclic phosphonate diester prodrugs could be prepared as illustrated in the following scheme. [0000] [0083] Phosphonylation of compound 3 gave phosphonate 10 which was deprotected using 48% HBr to give phosphonic acid 11. Treatment of compound 11 with POCl 3 gave the reactive dichlorophosphonates 12 which was immediately coupled with diol 20 ( J. Am. Chem. Soc. 2004, 5154) to give compound 13. Reduction of the nitro group in compound 13 followed by reaction with compound 17 and then thermal ring closure to give phenantholine 16 wherein R is H (compounds of formula I wherein X is OH, R 1 and R 2 together form a cyclic group). [0084] Another prodrug group can be introduced for expected properties. For example, compound 16c reacted with chlorophosphate under suitable base (for example: Et 3 N) and catalyst (for example: 4-dimethylaminopyridine) in suitable solvent (for example: CH 2 Cl 2 ) to yield phosphate 21. The deprotection of diethyl phosphate can be achieved by using common phosphate deprotecting reagent. For example, deprotection of phosphate 21 by trimethylsilyl bromide gave phosphoric acid 22, which can be converted to desired salt. For example, compound 22 mixed with sodium bicarbonate in water and methanol could give disodium salt 23. [0000] [0085] In another example, other types of prodrugs could be formed for different expected properties. For example, di-t-butylchloromethyl phosphate reacted with phenanthroline 16c under suitable base (for example: K 2 CO 3 ) in suitable solvent (for example: DMSO) to afford phosphate ester 24 and 25. Common t-butyl deprotecting agent could be used to remove di-t-butyl groups. For example, deprotection of 24 and 25 with trifluoroacetic acid in dichloromethane gave phosphoric acid 26 and 27, respectively. Compound 26 and 27 could be further converted to desired salts. [0000] EXAMPLES [0086] The compounds used in this invention and their preparation can be understood further by the Examples. These Examples should not however be construed as specifically limiting the invention, and variations of the compounds, now known or later developed, are considered to fall within the scope of the present invention as hereinafter claimed. Example 1 Syntheses of Compounds The preparation of 8-nitroquinoline (2c) [0087] [0088] A mixture was prepared to which 47 g of H 2 SO 4 , 20 ml of H 2 O, 23.4 g (0.104 mol) of sodium 3-nitrobenzene sulfonate, and 22 ml of glycerol were added in that order. It was warmed gently until forming a solution, and 11 g 2-nitroaniline 1c (0.08 mol) was added in portions. The mixture was refluxed for 5 h. After cooling to room temperature, the mixture was poured into 600 ml H 2 O under ice bath, adjusted to pH 6-7 with aqueous ammonia, and suction-filtered. The cake was dried and purified with chromatography (EA:PE=1:5). A yellow solid 2c 6.177 g was given in 44%. [0089] 1H NMR (300 MHz, CDCl3) δ 9.09 (dd, J=1.8 Hz, 4.5 Hz, 1H), 8.28 (dd, J=1.8 Hz, 8.4 Hz, 1H), 8.05 (d, J=9 Hz, 2H), 7.66-7.55 (m, 2H). The preparation of 3-bromo-8-nitroquinoline (3c) [0090] [0091] 8-nitroquinoline 2c 6.177 g (35.5 mmol) was added to 110 ml of acetic acid, and then 6.651 g NBS (35.5 mmol) was added. The mixture reacted at 50° C. for 2 h. The reaction mixture was cooled and poured into 600 ml H 2 O, and suction-filtered. The cake was dried and purified with chromatography (EA:PE=1:15) to give yellow solid 3c 2.625 g in 29%. [0092] 1H NMR (300 MHz, CDCl3) δ9.06 (d, J=2.1 Hz, 1H), 8.44 (d, J=2.4 Hz, 1H), 8.06 (d, J=7.5 Hz, 1H), 7.98 (d, J=8.1 Hz, 1H), 7.67 (t, J=7.8 Hz, 1H). The preparation of 3-bromoquinolin-8-amine (4c) [0093] [0094] Compound 3c (13.0 g, 51.6 mmol) was added to EtOH (150 mL), and then iron powder (11.6 g, 206.4 mmol), NH 4 Cl (11.0 g, 206.4 mmol) was added. The resulting was refluxed for overnight. The reaction mixture was cooled and filtered through celite. The filtrate was evaporated to dryness and purified with chromatography (EA:PE=1:5). A yellow solid 4c 8.23 g was given in 72%. [0095] 1H NMR (300 MHz, CDCl3) δ 8.72 (d, J=2.1 Hz 1H), 8.21 (d, J=2.1 Hz, 1H), 7.35 (t, J=7.8 Hz, 1H), 7.05 (dd, J=1.2 Hz, 8.1 Hz, 1H), 7.61 (dd, J=1.2 Hz, 7.5 Hz, 1H), 4.98 (s, 2H). The preparation of Diethyl 8-aminoquinolin-3-yl phosphonate (5c) [0096] [0097] Compound 4c (4.0 g, 17.9 mmol) was added to EtOH (53 mL) under N 2 , and then HPO(OEt) 2 (3.0 mL, 23.3 mmol), TEA (3.7 mL, 26.9 mmol), Ph 3 P (1.27 g, 4.8 mmol) and Pd(OAc) 2 (0.8 g, 3.58 mmol) was added. The resulting mixture was refluxed for overnight. The reaction mixture was cooled to room temperature and charged with H 2 O (100 mL), extracted with EA. The organic layers was merged, washed with brine, dried over anhydrous Na 2 SO 4 , concentrated, and purified with chromatography (EA:PE=1:1). A yellow oil 5c 1.4 g was given in 25%. [0098] 1H NMR (300 MHz, CDCl3) δ 8.98 (dd, J=1.8 Hz, 4.2 Hz, 1H), 8.59 (dd, J=2.1 Hz, 15.3 Hz, 1H), 7.38 (d, J=7.8 Hz, 1H), 7.21 (d, J=7.5 Hz, 1H), 7.01 (t, J=7.5 Hz, 1H), 4.20-4.07 (m, 4H), 1.35 (t, J=6.9 Hz, 6H) The preparation of Diethyl 8-((2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)methylamino)quinolin-3-yl phosphonate (6c) [0099] [0100] Compound 5c (1.4 g, 5 mmol) was added to EtOH (40 mL) under N 2 , and then compound 17 was added. The reaction mixture was refluxed for overnight. The reaction mixture was cooled to room temperature, evaporated the solvent and purified with chromatography (EA:PE=1:1). A yellow solid 6c 1.125 g was given in 52%. [0101] 1H NMR (300 MHz, CDCl3) δ 12.8 (d, J=15 Hz, 1H), 9.20 (dd, J=1.8 Hz, 4.2 Hz, 1H), 8.91 (d, J=14.7 Hz, 1H), 8.74 (dd, J=1.8 Hz, 15.3 Hz 1H), 7.80-7.76 (m, 2H), 7.67 (t, J=7.8 Hz, 1H), 4.30-4.09 (m, 4H), 1.81 (s, 6H), 1.35 (t, J=6.9 Hz, 6H). The preparation of Diethyl 7-hydroxy-1,10-phenanthrolin-3-yl phosphonate (7c) [0102] [0103] Diphenyl ether was heated to boiling, compound 6c (1.1 g, 2.5 mmol) was added to rapidly. The resulting mixture was stirred for 2 min at reflux. The mixture was cooled to 100° C., poured into PE (640 mL) under stirring, suction-filtered. The cake was purified with chromatography (MeOH:DCM=1:20). A yellow solid 7c 650 mg was given in 77%. [0104] 1H NMR (300 MHz, CDCl3) δ 10.8 (s, 1H), 9.31 (dd, J=1.8 Hz, 5.1 Hz, 1H), 8.72 (dd, J=1.8 Hz, 14.7 Hz, 1H), 8.49 (d, J=8.7 Hz, 1H), 7.94 (d, J=7.5 Hz, 1H), 7.71 (d, J=9 Hz, 1H), 6.62 (d, J=7.5 Hz, 1H), 4.35-4.14 (m, 4H), 1.39 (t, J=6.9 Hz, 6H). The preparation of 7-hydroxy-1,10-phenanthrolin-3-yl phosphonic acid (9c) [0105] [0106] Compound 7c (650 mg) was added to 48% HBr aq. The resulting mixture was refluxed for overnight. The reaction mixture was cooled to room temperature, evaporated the solvent, stirred with a small amount of water, suction-filtered, and dried. A gray solid 9c 513 mg was given in 95%. [0107] 1H NMR (300 MHz, D2O) δ 8.99 (dd, J=4.5 Hz, 1.8 Hz, 1H), 8.30 (dd, J=12.6 Hz, 1.8 Hz, 1H), 7.62□ (d, J=6.9 Hz, 1H), 740 (d, J=8.7 Hz, 1H), 7.26 (d, J=8.7 Hz, 1H), 6.19 (d, J=7.2 Hz, 1H). The preparation of Diethyl 8-nitroquinolin-3-yl phosphonate (10c) [0108] [0109] Compound 3c (30 g), KOAc (23.4 g), HPO(OEt) 2 (18.4 mL), toluene (300 mL) and Pd(dppf) 2 Cl 2 .CH 2 Cl 2 (1 g) were added to flask in sequence under N 2 . The resulting mixture was refluxed for 3 hours, diluted with EtOAc, filtered through Silica gel, and concentrated to afford 10c 46 g. [0110] 1H NMR (300 MHz, CDCl3) δ 9.28 (dd, J=1.8 Hz, 4.2 Hz, 1H), 8.82 (dd, J=1.8 Hz, 15 Hz, 1H), 8.16 (t, J=6 Hz, 2H), 7.21 (d, J=7.5 Hz, 1H), 7.74 (t, J=8.1 Hz, 1H), 4.33-4.11 (m, 4H), 1.37 (t, J=6.9 Hz, 6H). The preparation of 8-nitroquinolin-3-yl phosphonic acid (11c) [0111] [0112] Compound 10c (44.5 g) was added to 48% HBraq (230 mL). The resulting mixture was refluxed for 4 hours. The mixture was cooled, evaporated to dryness. The solid was washed with EtOH/EtOAc for 2 hours, and suction-filtered. A yellow solid 11c 31.5 g was given. [0113] 1H NMR (300 MHz, D20) δ 9.18 (dd, J=□1.8 Hz, 6 Hz, 1H), 8.98 (dd, J=1.8 Hz, 13.2 Hz, 1H), 8.54 (d, J=7.8 Hz, 1H), 8.36 (d, J=8.4 Hz, 1H), 7.81 (t, J=7.8 Hz, 1H). [0114] The preparation of 8-nitroquinolin-3-yl phosphonic dichloride (12c) [0000] [0115] Compound 11c (50.3 g) was added to dichloroethane (650 mL), and then DMF (3.6 mL) was added. Then (COCl) 2 (42 mL) was added dropwise under ice bath. After the addition was complete, the resulting mixture was refluxed for overnight. The mixture was cooled, and evaporated to dryness to yield 12c which was immediately used in the subsequent reaction. The preparation of (4S)-4-(3-chlorophenyl)-2-(8-nitroquinolin-3-yl)-1,3,2-dioxaphosphinan-2-one (13c) [0116] [0117] (S)-1-(3-chlorophenyl)propane-1,3-diol (36.95 g) 20 was added to CH 2 Cl 2 (540 mL). Then TiCl 4 was added (22 mL) dropwise under −78° C. The mixture was stirred for 5 minutes, and then stirred for 5 minutes under ice bath. TEA (110 mL) was added to the mixture. The resulting mixture was added dropwise to the solution of compound 12c in dichloromethane. After the addition was complete, the resulting mixture reacted at room temperature for overnight. The reaction mixture was diluted with CH 2 Cl 2 (700 mL), charged with 10% tartaric acid (210 mL), and stirred for 2 minutes. The mixture was filtered through celite, extracted with CH 2 Cl 2 . The organic layer was dried over Na 2 SO 4 , and the solvent removed. The residue was recrystallized twice from CH 3 CN. A yellow solid 13c 35.5 g was given in 44%. m/z: 405.1 [M+1]; The preparation of (4S)-4-(3-chlorophenyl)-2-(8-aminoquinolin-3-yl)-1,3,2-dioxaphosphinan-2-one (14c) [0118] [0119] Compound 13c (62.9 g) was added to EtOH (160 mL) and AcOH (160 mL). Then Fe (43.6 g) was added. The resulting mixture reacted at 40° C. for 10 minutes, cooled, adjusted to pH 6 with sat. NaHCO 3 solution, extracted with CH 2 Cl 2 . The organic layer was dried over Na 2 SO 4 , and evaporated. A yellow solid 14c 50 g was given in 86%. m/z: 375.0 [M+1]; The preparation of (4S)-4-(3-chlorophenyl)-2-(8-((2,2-dimethyl-1,3-dioxane-4,6-dione)-5-methylene)aminoquinolin-3-yl)-1,3,2-dioxaphosphinan-2-one (15c) [0120] [0121] Compound 14c (49 g) was added to EtOH (320 mL). then 5-(ethoxymethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione 17 (31.4 g) was added. The resulting mixture was refluxed for 2 hours, cooled, and suction-filtered. A yellow solid 15c 60 g was given in 87%. m/z: 529.0 [M+1], 471.0 was found. The preparation of (4S)-4-(3-chlorophenyl)-2-(7-hydroxy-1,10-phenanthrolin-3-yl)-1,3,2-dioxaphosphinan-2-one (16c) [0122] [0123] Diphenyl ether was heated to boiling, compound 15c (3 g) was added to rapidly. The resulting mixture was refluxed for 50 s. The mixture was cooled to 100° C., poured into petroleum ether, and suction-filtered. The cake was purified with chromatography (DCM:MeOH=30:1). A yellow solid 16c 1.676 g was given in 70%. [0124] 1H NMR (300 MHz, DMSO) δ 12.53 (s, 1H), 9.34 (dd, J=2.1 Hz, 5.1 Hz, 1H), 9.15 (dd, J=1.8 Hz, 15.3 Hz, 1H), 8.27 (d, J=8.7 Hz, 1H), 8.12-7.98 (m, 2H), 7.56 (s, 1H), 7.47-7.43 (m, 3H), 6.36 (d, J=7.2 Hz, 1H), 5.96 (d, J=11.1 Hz, 1H), 4.88-4.76 (m, 1H), 4.65-4.55 (m, 1H), 2.68-2.54 (m, 1H), 2.34-2.22 (m, 1H). The preparation of methyl 3-(3-chlorophenyl)-3-oxopropanoate (18) [0125] [0126] Potassium t-butoxide (15 g) was added to THF (50 mL) under nitrogen. The mixture was stirred at room temperature for 15 minutes. 1-(3-chlorophenyl) ethanone (10 g) and dimethyl carbonate (11 mL) was added slowly to the flask under ice bath. The mixture was stirred at room temperature for 1.5 hour. The reaction mixture was charged with water (40 mL) and concentrated hydrochloric acid (1.3 ml) and stirred for 15 minutes. [0127] The organic layers were separated and the aqueous phase was extracted again with toluene. The combined organic extracts were washed with saturated brine, dried with NaSO 4 , filtered and evaporated to dryness. A brown oil 18 13.22 g was given in 96%. The preparation of (3S)-methyl 3-(3-chlorophenyl)-3-hydroxypropanoate (19) [0128] [0129] The triethylamine (5.38 g) was added dropwise slowly to formic acid (9.8 g) under nitrogen under ice bath. After the addition was complete, the mixture was stirred for 20 minutes and then reacted at room temperature for 1 hour. Compound 18 (11.3 g), DMF (45 mL) and (S,S)-Ts-DPEN-Ru—Cl-(p-cymene) (68 mg) were added to the flask. The resulting mixture reacted at 60° C. for overnight, was cooled to room temperature, charged with water (100 mL), extracted with EA. The organic layer was washed with brine, dried over anhydrous Na 2 SO 4 , filtered, evaporated to dryness, and purified with chromatography (EA:PE=1:10). A jacinth oil 10.434 g was given in 91%. [0130] 1H NMR (300 MHz, CDCl3) δ 7.45 (s, 1H), 7.37-7.27 (m, 3H), 5.16 (t, J=6.9 Hz, 1H), 3.78 (s, 3H), 2.78 (d, J=1.8 Hz, 1H), 2.76 (s, 1H). The preparation of (1S)-1-(3-chlorophenyl)propane-1,3-diol (20) [0131] [0132] Sodium borohydride (1.84 g) and water (0.62 mL) were added to 1-butanol (37.5 mL), and then the solution of compound 19 (10.4 g) in 1-butanol (3.8 mL) was added dropwise to under ice bath. After addition was complete, the mixture was stirred for 0.5 h, and reacted at 90° C. for 4 h. The reaction mixture was cooled to room temperature, charged with aqueous potassium carbonate solution (10%, 23 mL), and stirred for 10 min. The organic layers were separated, washed with aqueous potassium carbonate solution (10 wt/vol %, 8 mL) and brine (8 mL), dried over anhydrous Na 2 SO 4 , filtered, evaporated to dryness, and purified with chromatography (DCM:CH 3 OH=30:1). A yellow oil 20 7.75 g was given in 85.5%. [0133] 1H NMR (300 MHz, CDCl3) δ 7.36 (s, 1H), 7.30-7.20 (m, 3H), 4.92 (q, J=4.5□Hz, 7.8 Hz, 1H), 3.90-3.79 (m, 2H), 2.82 (s, 2H), 2.03-1.85 (m, 2H). The preparation of 3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-yl phosphoric acid (22) [0134] [0135] Compound 16c (2 g) was dissolved in dichloromethane (100 mL). Triethylamine (2 mL) and 4-dimethylamino pyridine (57 mg) were added to the reaction mixture. The reaction mixture was putted under ice bath. Diethyl chlorophosphate (2 mL) in dichloromethane (20 mL) was added dropwise slowly to the reaction mixture. The mixture was allowed to react for one hour under ice bath and then 2 hours at room temperature. The reaction mixture was poured into saturated brine (200 mL). The organic layer was separated and the aqueous layer was extracted with dichloromethane. The organic layers were combined, dried over anhydrous sodium sulfate, rotary evaporated to dryness, and purified with chromatography (DCM:CH 3 OH=100:1) to yield 21 1.7 g. 21 (1.7 g) was dissolved in DCM (2 mL). Trimethylsilyl bromide (4 mL) was added to the mixture in one time under ice bath. After reacted 1 hr under ice bath, diethyl ether (50 mL) was added to the reaction mixture. The resulting mixture was filtered. The cake was collected, dissolved in methanol (20 mL), and stirred for 10 minutes. The reaction mixture was rotary evaporated to dryness and purified with chromatography (DCM:CH 3 OH:CH 3 COOH=20:1:0.05 DCM:H 3 OH=4:1). A white solid 22 600 mg was given in 25% yield. [0136] m/z: 507.0 [M+1]; [0137] □1H NMR (300 MHz, dmso) δ 13.84 (m, 1H), □9.27 (dd, J=4.8, 1.8 Hz, 1H), 8.99 (dd, J=14.3, 1.8 Hz, 1H), 8.39 (d, J=7.1 Hz, 1H), 8.30 (d, J=8.9 Hz, 1H), 8.13 (d, J=9.0 Hz, 1H), 7.50 (s, 1H), 7.45-7.38 (m, 1H), 7.35-7.25 (m, 2H), 6.85 (d, J=7.1 Hz, 1H), 5.35 (dd, J=9.0, 5.9 Hz, 1H), 4.11-3.98 (m, 2H), 2.68-2.55 (m, 1H), 2.50-2.34 (m, 1H). The preparation of Disodium 3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-yl phosphate (23) [0138] [0139] Compound 22 (500 mg) was suspended to methanol (10 mL), 1N NaHCO 3 solution (2 mL) was added to the mixture slowly at room temperature. The reaction mixture was allowed to stir for 20 minutes, and evaporated to dryness. A white solid 23 540 mg was given in 100% yield. [0140] m/z: 550.0 [M+1], found 507; [0141] 1H NMR (300 MHz, dmso) δ 9.27 (dd, J=4.8, 1.8 Hz, 1H), 8.99 (dd, J=14.3, 1.8 Hz, 1H), 8.39 (d, J=7.1 Hz, 1H), 8.30 (d, J=8.9 Hz, 1H), 8.13 (d, J=9.0 Hz, 1H), 7.50 (s, 1H), 7.45-7.38 (m, 1H), 7.35-7.25 (m, 2H), 6.85 (d, J=7.1 Hz, 1H), 5.35 (dd, J=9.0, 5.9 Hz, 1H), 4.11-3.98 (m, 2H), 2.68-2.55 (m, 1H), 2.50-2.34 (m, 1H). The preparation of di-t-butyl (3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-oxy)-7-methyl phosphate (24) and di-t-butyl (3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-one)-10(7H)-methyl phosphate (25) [0142] [0143] Compound 16c (200 mg, 0.47 mmol) was dissolved in DMSO (2 mL). Potassium carbonate (195 mg, 1.41 mmol) was added to the reaction mixture. The resulting mixture was stirred for 15 minutes under 30° C. Di-t-butyl chloromethyl phosphate (146 mg, 0.56 mmol) was added to the reaction mixture and the resulting mixture reacted at 30° C. for overnight. The reaction mixture was poured into saturated brine (20 mL). The organic layer was separated and the aqueous layer extracted with dichloromethane. The organic layers were combined, dried over sodium sulfate, rotary evaporated to dryness and purified with chromatography (EA) to yield intermediate 24 and 25. [0144] m/z: 649.2[M+1]; [0145] Compound 24: [0146] 1H NMR (300 MHz, dmso) δ 9.48 (dd, J=4.9, 1.9 Hz, 1H), 9.14 (dd, J=15.4, 1.9 Hz, 1H), 9.10 (d, J=5.3 Hz, 1H), 8.31 (d, J=9.1 Hz, 1H), 7.63-7.58 (m, 2H), 7.55-7.41 (m, 3H), 6.11-5.91 (m, 3H), 4.92-4.75 (m, 1H), 4.71-4.53 (m, 1H), 2.73-2.55 (m, 1H), 2.36-2.19 (m, 1H), 1.37 (s, 18H) [0147] 13C NMR (75 MHz, dmso) δ 158.59, 151.37, 150.71, 150.54, 147.15, 146.18, 142.12, 142.01, 141.71, 133.29, 130.57, 128.41, 126.26, 125.79, 124.59, 121.53, 120.83, 106.97, 87.59, 82.98, 77.56, 66.24, 33.30, 29.38 [0148] Compound 25: [0149] 1H NMR (300 MHz, dmso) δ 9.39 (dd, J=4.6, 2.1 Hz, 1H), 9.19 (dd, J=15.6, 2.0 Hz, 1H), 8.43 (d, J=8.7 Hz, 1H), 8.22 (d, J=8.1 Hz, 1H), 8.18 (d, J=8.4 Hz, 1H), 7.58 (s, 1H), 7.50-7.44 (m, 3H), 7.18-6.99 (m, 2H), 6.49 (d, J=7.9 Hz, 1H), 5.98 (d, J=11.2 Hz, 1H), 4.93-4.72 (m, 1H), 4.69-4.49 (m, 1H), 2.72-2.52 (m, 1H), 2.34-2.19 (m, 1H), 1.21 (s, 9H), 1.19 (s, 9H). [0150] 13C NMR (75 MHz, dmso) δ 176.22, □148.52, 147.50, 142.91, 141.99, 141.88, 136.23, 133.28, 130.54, 129.08, 128.91, 128.46, 125.72, 125.00, 124.60, 124.08, 121.52, 112.53, 82.30, 80.38, 77.54, 66.52, 33.21, 29.16. (3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-oxy)-7-methyl phosphoric acid (26) [0151] [0152] Compound 24 (50 mg, 0.08 mmol) was dissolved in dichloromethane (3 mL). TFA (1 mL) was added to the mixture at room temperature. The reaction mixture was stirred for 30 minutes at room temperature. The reaction mixture was evaporated to dryness. Methanol (1 mL) was added to the residue, and the mixture was suction-filtered to afford compound 26. [0153] 1H NMR (300 MHz, dmso) δ 9.46 (dd, J=05.0, 1.8 Hz, 1H), 9.23-9.05 (m, 2H), 8.37-8.21 (m, 2H), 7.68 (d, J=5.6 Hz, 1H), 7.56 (s, 1H), 7.51-7.36 (m, 3H), 6.12-5.90 (m, 3H), 4.90-4.74 (m, 1H), 4.71-4.50 (m, 1H), 2.71-2.54 (m, 1H), 2.33-2.21 (m, 1H) The preparation of (3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-one)-10(7H)-methyl phosphoric acid (27) [0154] [0155] Compound 25 (50 mg, 0.08 mmol) was dissolved in dichloromethane (3 mL). TFA (1 mL) was added to the mixture at room temperature. The reaction mixture was stirred for 30 minutes at room temperature. The reaction mixture was evaporated to dryness. Methanol (1 mL) was added to the residue, and the mixture was suction-filtered to afford compound 27. [0156] 1H NMR (300 MHz, dmso) δ 9.38 (dd, J=4.5, 2.0 Hz, 1H), 9.13 (dd, J=15.6, 2.0 Hz, 1H), 8.40 (d, J=8.7 Hz, 1H), 8.19 (d, J=8.3 Hz, 1H), 8.13 (d, J=8.7 Hz, 1H), 7.58 (s, 1H), 7.54-7.35 (m, 3H), 7.04 (t, J=9.9 Hz, 1H), 6.91 (t, J=9.8 Hz, 1H), 6.43 (d, J=7.8 Hz, 1H), 5.95 (d, J=10.8 Hz, 1H), 4.88-4.76 (m, 1H), 4.69-4.45 (m, 1H), 2.74-2.56 (m, 1H), 2.31-2.22 (m, 1H). Example 2 Expression and Purification of P4H [0157] Human recombinant P4H was expressed in E. coli . Briefly, DNA encoding the signal sequence of P4H was cloned into pET28_N-His_TEV, the resulting plasmid pET28_N-His_TEV_P4HA1/PDI was transferred to E. coli Origami2(DE3) to co-expressed. The enzyme obtained was purified with MonoQ ion-exchange column, TEV digested and confirmed by MS, passed through Histrap HP column, finally purified with Hiload16/60 superdex 200 column. Example 3 Assays of the Enzymatic Activity of P4H and the Influence of the Compound of the Present Invention to the Enzymatic Activity [0158] The measurement of the enzymatic activity of purified P4H zymoprotein and the assay of the influence of the compound to the enzymatic activity were performed at the following coupling enzymatic reaction system: 100 mM Tris (pH7.0), 0.1 mM (NH 4 ) 2 Fe(SO 4 ) 2 , 0.1 mM ascorbic acid, 0.2 mM CoA, 0.2 mM ATP, 0.5 uM succinyl CoA synthase, 100 uM 2-oxoglutarate, 100 uM (Pro-Pro-Gly) 10 peptide, 50 nM P4H enzyme, 50 ul total. After 45 min reaction at 25° C., 10 ul MLG R1 was added and reacted for 10 min, 10 ul MLG R2 was added and reacted for 20 min. P4H catalyst 2-oxoglutaric acid and polypeptide with coenzyme and suitable enzyme reaction environment to give product succinic acid. The product succinic acid then produced succinyl CoA and phosphoric acid with the action of succinyl CoA synthase. The level of generated phosphoric acid could be measured by MLG, which reflects the level of P4H. The generated green product (MG+)(H 2 PMo 12 O 40 ) was measured at OD 630 nm. [0159] The evaluation of the inhibition of compound about P4H enzyme was performed in 96-well plates. Every concentration has two duplicate samples (n=2). Compound 9c was added to the enzymatic reaction system in following concentrations (in sequence and before the addition of P4H enzyme): 0.01, 0.03, 0.1, 0.3, 1, 3, 30, 100, 300 nM. Data analysis and statistics was performed by Prism. IC50 of compound 9c to enzyme is 8.1 μM ( FIG. 1 ). FIG. 1 indicates, the inhibition of compound 9c to the activity of human P4H enzyme is higher as the concentration of 9c is higher. Example 4 Studies of In-Vivo Pharmacokinetic [0160] Wistar rats (200±20 g) were divided into 2 groups, 6 each, half female and half male in each group, ate and drank freely. The first group was given compound 16c 3 mg·kg −1 caudal-intravenously. The second group was orally administered disodium salt of compound 27 (39 mg·kg −1 ). Blood (0.3 mL) was collected from retroorbital vein at time point 0 h, 0.08 h, 0.17 h, 0.33 h, 0.5 h, 0.75 h, 1 h, 1.5 h, 2 h, 3 h, 5 h, 7 h, placed into cold heparinized Eppendorf tubes. The samples were centrifuged at 4° C. (15000 rpm) for 5 min. Transfer 100 μL plasma sample to −80° C. freezer for test. [0161] Quantitative LC-MS/MS analysis methods of compound 9c and prodrug 16c in plasma were set up, using diazepam and mildronate as internal standard, respectively. (Prodrug 27 was not detected under experimental condition from plasma) the plasma sample was tested and analyzed. (result see in Table 1 and FIG. 2 ) [0000] TABLE 1 The concentration of compound 16c in plasma after compound 16c iv dosing and compound 27 PO dosing Route of Com- adminis- C max * t 1/2 ** AUC 0-t *** AUC 0-∞ **** pound tration (ng · mL −1 ) (h) (μg · h · L −1 ) (μg · h · L −1 ) 16c IV 1617.80 1.50 2064.58 2136.40 27  PO 1440 2.79 5235.70 6805.74 *C max refers to peak concentration in plasma **t 1/2 refers to half life of drug in plasma ***AUC 0-t refers to area under concentration-time curve until final test time ****AUC 0-∞ refers to area under concentration-time curve until total clearance of drug Oral Bioavailability: [0162] Oral Bioavailability was calculated according to compound 16c in plasma. Area under concentration-time curve (AUC) of PO dosing was divided by AUC of iv dosing of same amount of drugs, expressed as absorption percentage: Bioavailability (F)=AUCpo·Miv/AUCiv·Mpo×100%. Wherein, Miv means the molar concentration of drugs by iv dosing, and Mpo means the molar concentration of drugs by PO dosing. The AUC 0-t of compound 16c in plasma [0163] After compound 16c (3 mg·kg −1 ) was intravenously administered and compound 27 (39 mg·kg −1 ) was orally administered, the AUC 0-t of compound 16c in plasma is 2064.58 g·h/mL and 5235.70 g·h/mL, respectively. Based on the concentration of compound 16c in plasma, the bioavailability (F) of compound 27 is 25.4% (i.e 5235.70/(2064.58×10)×100%). Concentration of Compound 16c and 9c in Liver: [0164] 16 Wistar rats (200±20 g) were divided into 4 groups randomly, female and male each half in each group, ate and drank freely before the experiment. After PO dosing of compound 27 (39 mg·kg −1 ), rats were sacrificed at each time point 15 min, 45 min, 8 h, 24 h. Liver samples were collected, washed off blood and contents with saline, cut into small pieces, and stirred evenly. 1 g was weighed. 1 mL Methanol/water was added. After homogenated, additional 1 mL methanol/water was added. The mixture was sonicated for 15 seconds, centrifuged (4500 rpm) for 10 minutes. The upper clear solution was tested using LC-MS/MS method to give the concentration of compound 16c and 9c in liver at different time points after administration (table 2). The results indicate that prodrug 27 converted to compound 16c in rat after PO dosing, and compound 16c converted to compound 9c in liver. [0000] TABLE 2 concentration of compound 16c and 9c (ng · g −1 )in liver at different time points after oral administration of compound 27 0.25 h 0.75 h 8 h 24 h 16c 521.50 662.5 584.50 50.88  9c 16.13 64.25 44.68 3.55 Example 5 Study of In-Vivo Pharmaceutical Efficacy [0165] This experiment used Bile Duct Ligation to induce liver fibrosis model in rats. Treatment of BDL rats with PO dosing prodrug 27 was studied. [0166] Briefly, Wistar rats (200±20 g) were divided into 3 groups, half female and half male in each group: [0167] SHAM group: 6 rats were anaesthetized, the abdominal skin was shaved and sterilized regularly, the common bile duct was exposed by an upper abdominal midline incision with sterile operation. Muscle and skins were sutured separately. [0168] liver fibrosis MODEL group: 12 rats were anaesthetized, the abdominal skin was shaved and sterilized regularly, the common bile duct was exposed and ligated by an upper abdominal midline incision with sterile operation. Muscle and skins were sutured separately. [0169] Dosing group: 12 rats were anaesthetized, the abdominal skin was shaved and sterilized regularly, the common bile duct was exposed and ligated by an upper abdominal midline incision with sterile operation. Muscle and skins were sutured separately. After operation, disodium salt of compound 27 (30 mg/kg) was dissolved in water and dosed orally to the rats once per day test indexes: [0170] After 2 weeks, measure the ALT and AST of serium and liver homogenate [0171] After 2 weeks, rats were sacrificed, and liver performed HE staining and Masson staining. The Influence of Compound 27 Orally Administrated on the ALT and AST of the Serium and Liver Homogenate of BDL Rats Having Liver Fibrosis [0172] ALT and AST were liver function index in common clinical use now. ALT mainly exists in the cytosol of hepatocyte, AST mainly exists in the mitochondria of hepatocyte. When hepatocyte is damaged, the level of ALT and AST in serium rise, which could reflect the level of the damage of hepatocyte. The ALT and AST of the serium and liver homogenate of rats in model group with BDL rised significantly. After compound 27 was administrated for 14 days, animals were sacrificed. The ALT and AST of the serium and liver homogenate of those animal decreased significantly, which have significant difference comparing with model group (**P<0.01, see on Table 3 and Table 4). It's indicated that compound 27 alleviated the level of the damage of liver function with BDL, and have protection effect to liver damage resulted from bile regurgitation. [0000] TABLE 3 The influence of compound 27 on the ALT (IU/L) of the serium of BDL rats having liver fibrosis groups ALT in serum ALT in liver SHAM 67.1 ± 5.45 68.2 ± 8.33 MODEL 144.4 ± 15.94 136.8 ± 16.48 Compound 27   74.4 ± 17.82**   76.4 ± 11.35** (30 mg/kg) **P < 0.01, compared to MODEL group [0000] TABLE 4 The influence of compound 27 on the AST (IU/L) of the serium of BDL rats having liver fibrosis groups AST in serum AST in liver SHAM 67.7 ± 4.67 67.40 ± 5.28 MODEL 207.2 ± 30.96 198.75 ± 27.70 Compound 27   87.2 ± 12.51**  91.42 ± 8.79** (30 mg/kg) **P < 0.01, compared to MODEL group The Influence of Compound 27 Orally Administrated on the HE Staining of BDL Rats Having Liver Fibrosis [0173] H&E staining results as follow: [0174] Sham group: depicted in FIG. 3 , the structure of hepatic lobule is normal, hepatocytes centre on central veins and radiate out in all directions. The hepatocytes in hepatic lobule range in order. The size of hepatocytes is even. There is no the degeneration and necrosis of hepatocytes. [0175] Model group: depicted in FIG. 4 , the structure of hepatic lobule is inordinate. [0176] Hepatocytes swelling. The cytoplasm of hepatocytes is loose. The connective tissue of fibrosis proliferate. [0177] Dosing group: depicted in FIG. 5 , the treating group varies the pathological changes of hepatic tissue.
The present invention relates to a novel phenanthroline phosphonic acid compound and a pharmaceutical salt thereof, as well as an application of the compound and the pharmaceutical salt thereof as collagen prolyl hydroxylase inhibitors in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a National Stage of International Application No. PCT/CN2015/076273, filed Apr. 10, 2015 and published in Chinese as WO 2015/154716 on Oct. 15, 2015.", "This application claims priority to Chinese Application No. 201410142608.8, filed on Apr. 10, 2014.", "The entire disclosures of the above applications are incorporated herein by reference.", "FIELD OF INVENTION [0002] The present invention relates to pharmaceutical field, specially a novel phenanthroline phosphonic acid compound and a pharmaceutical salt thereof, preparation of the compound, as well as an application of the compound and the pharmaceutical salt thereof as collagen prolyl-4-hydroxylase inhibitors in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease.", "BACKGROUND [0003] The following description of the background of the invention is provided to aid in understanding the invention, but is not admitted to be, or to describe, prior art to the invention.", "All cited publications are incorporated by reference in their entirety.", "[0004] The foundation of hepatic fibrosis is that excess collagen (especially collagen I) is synthesized ( Clin.", "Sci.", "1997, 92, 103) by liver which deposits on extracellular matrix (EXM).", "The biosynthesis of collagen includes series of post-translational modification of procollagen.", "Five enzymes, 3 collagen hydroxylases and 2 collagen glycosyltransferases, are involved in this process.", "Among these hydroxylases, prolyl-4-hydroxylase (P4H) is a tetramer of 2 α subunits (P4Hα1, P4Hα2) and 2 β subunits.", "β Subunit is disulfide isomerase, and the main parts having catalytic effect locate in β Subunit, and the major role of α subunit is deciding the activity of the enzyme.", "Prolyl-4-hydroxylase is the rate limiting enzyme in the synthesis of 21 different collagen ( Critical Reviews in Biochemistry and Molecular Biology 2010, 45, 106).", "P4H locates in the endoplasmic reticulum, and catalyzes the formation of 4-hydroxyproline, from the proline residue on X-Pro-Gly sequence, in the presence of Fe 2+ , O 2 , 2-oxoglutarate and ascorbate.", "[0005] P4H hydroxylate proline to 4-hydorxyproline (4-HYP) in certain positions of the procollagen, thus enhances the stability of collagen by forming triple helixes under physiological circumstances.", "Conversely, with less 4-HYP content, the collagen is unable to form stable triple helixes structure and degrades ( Matrix Biol.", "2003, 22, 15).", "Therefore, inhibition of P4H activity is widely accepted as a valid method for controlling excess collagen synthesis (fibrosis).", "( Hepatol.", "1998, 28, 404).", "Several small molecule P4H inhibitors were verified to be effective in preventing collagen synthesis in vitro and in vivo ( J. Hepatol.", "1997, 27, 185 ;", "Hepatol.", "1996, 23, 755 ;", "Hepatol.", "1998, 28, 404 ;", "Biochem.", "J. 1994, 300, 525 ;", "J. Hepatol.", "1991, 13, S35).", "For example, P4H inhibitor HOE077 inhibits expression of procollagen mRNA and reduces hepatic stellate cells proliferation ( Hepatol.", "Res.", "2002, 23, 1 ;", "J. Hepatol.", "1997, 27, 185), also inhibits activation of hepatic stellate cells ( Hepatol.", "1996, 23, 755).", "The inhibitory effect of HOE077 on procollagen gene and protein was dose-dependent, but no effect on the synthesis of total protein of cell was observed.", "The inhibitory effect of HOE077 is possibly due to the inhibition of the expression of TIMP gene to expedite collagen degradation process ( J. Gastroenterol.", "1999, 34, 376).", "Several P4H inhibitors showed anti-fibrotic effects in various animal liver fibrosis models (CO 4 , TAA etc.).", "( Hepatol.", "1998, 28, 404 ;", "Hepatol.", "1996, 23, 755 ;", "J. Hepatol.", "1997, 27, 185).", "Another P4H inhibitor FG-041 (1,4-dihydrophenanthrol-4-one-3-carboxylic acid) was reported to prevent myocardial infarction in animal experiment ( Circulation 2001, 104, 2216).", "P4H inhibitors were also reported to prevent bladder block ( Urology 2012, 80, 1390).", "[0006] P4H exists everywhere in body.", "Thus, P4H inhibitors is targeted-delivered to diseased organ while the other normal organ don't be influenced, is the key to successful development of safe and effective P4H inhibitors.", "In 1990s, HOECHST (which is france sanofi now) firstly developed HOE077 to treat liver cirrhosis ( Hepatol.", "1996, 23, 755 ;", "J. Hepatol.", "1997, 27, 185).", "Preclinical experiments showed promising results though severe side effects (cataract) were observed in clinical trials.", "It is reported that inhibition of collagen synthesis could seriously influence the function of organ, such as eyes and kidneys ( J. Biol.", "Chem.", "2010, 285, 42023).", "Collagen synthesis widely exists in cellular matrix, therefore, the suppression of collagen synthesis of organ cell matrix results in the effusion of macromolecules, which cause the change of the organ function.", "Thus, the key to developing the P4H inhibitors used to treat organ fibrosis (such as liver fibrosis) is how to deliver the P4H inhibitors to specified organ.", "Prodrugs have been widely used in targeted therapeutic areas ( J. Pharmacol.", "Exp.", "Ther.", "2005, 312, 554).", "1,3-Propane diols could form cyclic phosphonate esters with phosphonic acids, which were reported liver targeting ( J. Med.", "Chem.", "2008, 51, 666).", "The liver prodrug-delivery which the present invention adopts is to modify the active component of the drug to inactive prodrug.", "The prodrug may only be metabolized under the catalysis of liver-specific enzymes, for example, cytochrome P450, to release the active component in liver, therefor the active component produce effect in liver.", "Content of the Present Invention [0007] The purpose of the present invention is to provide a novel phenantholine phosphonic acid compound and the pharmaceutical salt thereof.", "The another purpose of the present invention is to provide a preparation of the compound and the pharmaceutical salt thereof.", "The another purpose of the present invention is to provide an application of the compound and the pharmaceutical salt thereof as collagen prolyl-4-hydroxylase inhibitors in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease.", "[0008] In one aspect, the present invention provides compounds of Formula I or Formula II, and pharmaceutically acceptable salts thereof: [0000] [0009] Wherein, in Formula I: [0010] X is —Cl or —OR 3 ;", "R 3 is —H, —C(O)—(C 1 -C 6 alkyl), —PO(OH) 2 or —CH 2 OPO(OH) 2 ;", "[0011] Each of R 1 and R 2 can be independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and CH 2 OCOO—(C 1 -C 6 alkyl);", "or R 1 and R 2 join to form a group having the formula: [0000] [0012] Wherein Y is aryl or heteroaryl;", "[0013] In one aspect, X could be selected from —Cl, and —OR 3 , R 3 is —H, —C(O)—(C 1 -C 6 alkyl), —PO(OH) 2 or —CH 2 OPO(OH) 2 ;", "[0014] In another aspect, each of R 1 and R 2 could be independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and —CH 2 OCOO—(C 1 -C 6 alkyl);", "or R 1 and R 2 join to form a group having the formula: [0000] [0015] Wherein Y is aryl, heteroaryl;", "[0016] Wherein, in Formula II: [0017] Z is —H or —CH 2 OPO(OH) 2 ;", "each of R 1 and R 2 is independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and —CH 2 OCOO—(C 1 -C 6 alkyl);", "or R 1 and R 2 join to form a group having the formula: [0000] [0018] Wherein Y is aryl or heteroaryl.", "[0019] In one aspect, Z could be selected from —H, and CH 2 OPO(OH) 2 ;", "[0020] In another aspect, each of R 1 and R 2 can be independently selected from H, C 1 -C 6 alkyl, —CH 2 OCO—(C 1 -C 6 alkyl) and —CH 2 OCOO—(C 1 -C 6 alkyl);", "or R 1 and R 2 join to form a group having the formula: [0000] [0021] Wherein Y is aryl, heteroaryl.", "[0022] In a preferred embodiment, the compound have the following formula: [0000] [0023] In another preferred embodiment, the compound have the following formula: [0000] [0024] In another preferred embodiment, the compound have the following formula: [0000] [0025] In the second aspect, the present invention provides the method of preparing the phenantholine phosphonic acid compound and the pharmaceutical salt thereof.", "[0026] In the third aspect, the present invention provides an application of the phenantholine phosphonic acid compound and the pharmaceutical salt thereof as collagen prolyl-4-hydroxylase inhibitors in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease.", "[0027] The present invention provides an application of the compounds of Formula I or Formula II or the pharmaceutical salt thereof in the preparation of drugs for preventing or treating collagen prolyl-4-hydroxylase related disease.", "[0028] The present invention provides an application of the compounds of Formula I or Formula II, or the in vivo metabolite thereof, or the pharmaceutical salt thereof used as collagen prolyl-4-hydroxylase inhibitors.", "[0029] The present invention could protect liver function by administering to a patient with chronic liver injuries a therapeutically effective amount of the compound of Formula I and Formula II, or pharmaceutically acceptable salts thereof.", "[0030] The present invention could prevent and treat liver fibrosis by administering to a patient with chronic liver injuries a therapeutically effective amount of the compound of Formula I and Formula II, or pharmaceutically acceptable salts thereof.", "[0031] The present invention could prevent liver fibrosis by administering to a patient at risk for developing diabetes a therapeutically effective amount of the compound of Formula I and Formula II, or pharmaceutically acceptable salts thereof.", "DESCRIPTION OF FIGURES [0032] FIG. 1 .", "The IC50 of Compound 9c against P4H enzyme [0033] FIG. 2 .", "Concentration-time curve of compound 16c in plasma after iv dosing 16c (3 mg/kg) and PO dosing 27 (39 mg/kg).", "[0034] FIG. 3 .", "H&E staining of rat liver (SHAM group) [0035] FIG. 4 .", "H&E staining of rat liver (BDL 2 weeks) [0036] FIG. 5 .", "H&E staining of rat liver (BDL, PO administration of 27, 30 mpk, 2 weeks) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Definitions of Terms [0037] In accordance with the present invention and as used herein, the following terms are defined with the following meanings, unless explicitly stated otherwise.", "[0038] The term “alkyl”", "refers to saturated aliphatic groups including straight-chain, branched chain and cyclic groups, up to and including 20 carbon atoms.", "Suitable alkyl groups include methyl, ethyl, n-propyl, isopropyl, and cyclopropyl.", "The alkyl may be optionally substituted with 1-3 substituents.", "[0039] The term “aryl”", "refers to aromatic groups which have 5-14 ring atoms and at least one ring having a conjugated pi electron system and includes carbocyclic aryl, heterocyclic aryl, fused aryl and biaryl aryl, all of which may be optionally substituted.", "The aryl may be optionally substituted with 1-6 substituents.", "[0040] Heterocyclic aryl or heteroaryl groups are groups which have 5-14 ring atoms wherein 1 to 4 heteroatoms are ring atoms in the aromatic ring and the remainder of the ring atoms being carbon atoms.", "Suitable heteroatoms include oxygen, sulfur, nitrogen, and selenium.", "Suitable heteroarylgroups include furanyl, thienyl, pyridyl, pyrrolyl, N-lower alkyl pyrrolyl, pyridyl-N-oxide, pyrimidyl, pyrazinyl, imidazolyl, and the like, all optionally substituted.", "[0041] The term “optionally substituted”", "or “substituted”", "refers to the groups substituted by one to four substituents, independently selected from lower alkyl, lower aryl, lower aralkyl, lower cyclic alkyl, lower heterocycloalkyl, hydroxy, lower alkoxy, lower aryloxy, perhaloalkoxy, aralkoxy, lower heteroaryl, lower heteroaryloxy, lower heteroarylalkyl, lower heteroaralkoxy, azido, amino, halo, lower alkylthio, oxo, lower acylalkyl, lower carboxy esters, carboxyl, carboxamido, nitro, lower acyloxy, lower aminoalkyl, lower alkylaminoaryl, lower alkylaryl, lower alkylaminoalkyl, lower alkoxyaryl, lower arylamino, lower aralkylamino, sulfonyl, lower carboxamidoalkylaryl, lower carboxamidoaryl, lower hydroxyalkyl, lower haloalkyl, lower alkylaminoalkylcarboxy, lower aminocarboxamidoalkyl, cyano, lower alkoxyalkyl, lower perhaloalkyl, and lower arylalkyloxyalkyl.", "[0042] “Substituted aryl”", "and “substituted heteroaryl”", "refers to aryl and heteroarylgroups substituted with 1-6 substituents.", "These substituents are selected from lower alkyl, lower alkoxy, lower perhaloalkyl, halo, hydroxy, and amino.", "[0043] The term “halogen”", "or “halo”", "refers to —F, —Cl, —Br and —I.", "[0044] The phrase “therapeutically effective amount”", "means an amount of the compound or a combination of compounds needed to ameliorates, attenuates, eliminates or prevents, modifies, delays one or more of the symptoms of a particular disease The term “pharmaceutically acceptable salt”", "refers to the salts generated by mixing the compounds of Formula I or Formula II and the prodrug thereof with an organic or inorganic acid or base.", "Suitable acids include acetic acid, adipic acid, benzenesulfonic acid, (+)-7,7-dimethyl-2-oxobicyclo[2.2[.", "].1]heptane-1-methanesulfonic acid, citric acid, 1,2-ethanedisulfonic acid, dodecyl sulfonic acid, fumaric acid, glucoheptonic acid, gluconic acid, glucuronic acid, hippuric acid, hydrochloride hemiethanolic acid, HBr, HCl, HI, 2-hydroxyethanesulfonic acid, lactic acid, lactobionic acid, maleic acid, methanesulfonic acid, methylbromide acid, methyl sulfuric acid, 2-naphthalenesulfonic acid, nitric acid, oleic acid, 4,4′-methylenebis [3-hydroxy-2-naphthalenecarboxylic acid], phosphoric acid, polygalacturonic acid, stearic acid, succinic acid, sulfuric acid, sulfosalicylic acid, tannic acid, tartaric acid, terphthalic acid, and p-toluenesulfonic acid.", "The salt generated by mixing with suitable base is sodium salt, potassium salt, calcium salt, magnesium salt, lithium salt, cesium salt, amino acid salt.", "[0045] The term “patient”", "refers to a male or female mammal animal being treated, such as a dog, a cat, a cow, a horse, a sheep, and a human.", "[0046] The term “prodrug”", "as used herein refers to any compound that when administered to a biological system generates a biologically active compound as a result of spontaneous chemical reaction(s), enzyme catalyzed chemical reaction(s), and/or metabolic chemical reaction(s), or a combination of each.", "Standard prodrugs are formed using groups attached to functionality, e.g. HO—, HS—, HOOC—, R 2 N—, associated with the drug, that cleave in vivo.", "Standard prodrugs include but are not limited to carboxylate esters where the group is alkyl, aryl, aralkyl, acyloxyalkyl, alkoxycarbonyloxyalkyl, as well as acyl, alkoxycarbonyl, aminocarbonyl, phosphate or sulfate which attached to hydroxyl, thiol and amines.", "The groups illustrated are exemplary, not exhaustive, and one skilled in the art could prepare other known varieties of prodrugs.", "Such prodrugs of the compounds of Formula I and II fall within this scope.", "Prodrugs must undergo some form of a chemical transformation to produce the compound that is biologically active or is a precursor of the biologically active compound.", "In some cases, the prodrug is biologically active, usually less than the drug itself, and serves to improve drug efficacy or safety through improved oral bioavailability, pharmacodynamic half-life, etc.", "Prodrug forms of compounds may be utilized, for example, to improve bioavailability, improve subject acceptability by masking or reducing unpleasant characteristics such as bitter taste or gastrointestinal irritability, alter solubility for intravenous use, provide for prolonged or sustained release or delivery, improve ease of formulation, or provide site-specific delivery of the compound.", "Prodrugs are described in The Organic Chemistry of Drug Design and Drug Action, by Richard B. Silverman, Academic Press, San Diego, 1992.", "Chapter 8: “Prodrugs and Drug delivery Systems”", "pp. 352-401;", "Design of Prodrugs, edited by H. Bundgaard, Elsevier Science, Amsterdam, 1985;", "Design of Biopharmaceutical Properties through Prodrugs and Analogs, Ed.", "by E. B. Roche, American Pharmaceutical Association, Washington, 1977;", "and Drug Delivery Systems, ed.", "by R. L. Juliano, Oxford Univ.", "Press, Oxford, 1980.", "[0047] The term “percent enantiomeric excess (% ee)”", "refers to optical purity.", "It is obtained by the following formula: [0000] [ R ] - [ S ] [ R ] + [ S ] × 100 = %   R -  %   S [0048] wherein [R] represents the amount of the R isomer, and [S] represents the amount of the S isomer.", "This formula provides the % ee when R is the dominant isomer.", "[0049] The terms “treating”", "or “treatment”", "a disease, includes preventing the disease from occurring (prophylactic treatment), inhibiting the disease (slowing or arresting its development), providing relief from the symptoms or side-effects of the disease (including palliative treatment), and relieving the disease (causing regression of the disease).", "[0050] The formulations of the compound of the present patent: [0051] Compounds of the invention are administered in a total daily dose of 0.01 to 2500 mg.", "In one aspect, the range is about 5 mg to about 500 mg.", "The dose may be administered in as many divided doses as is convenient.", "[0052] Compounds of this invention when used in combination with other agents may be administered as a daily dose or an appropriate fraction of the daily dose (e.g., bid).", "The compounds of this invention may be used as a part of a multidrug regimen, also known as combination or ‘cocktail’ therapy, wherein, multiple agents may be administered together, may be administered separately at the same time or at different intervals, or administered sequentially.", "The compounds of this invention may be administered after a course of treatment by another agent, during a course of therapy with another agent, administered as part of a therapeutic regimen, or may be administered prior to therapy by another agent in a treatment program.", "[0053] For achieving the purpose of treatment, the compounds of this invention may be administered by a variety of means including orally, parenterally, by inhalation spray, topically, or rectally in formulations containing pharmaceutically acceptable carriers, adjuvants and vehicles.", "The term parenteral as used here includes subcutaneous, intravenous, intramuscular, and intraarterial injections with a variety of infusion techniques.", "Intraarterial and intravenous injection as used herein includes administration through catheters.", "Intravenous administration is generally preferred.", "Pharmaceutically acceptable salts include sodium salt, potassium salt, calcium salt, magnesium salt, lithium salt, cesium salt, amino acid salt, acetate, adipate, besylate, bromide, camsylate, hydrochloride, citrate, edisylate, estolate, fumarate, gluceptate, gluconate, glucoranate, hippurate, hyclate, bromide, chloride, iodide, isethionate, lactate, lactobionate, maleate, mesylate, methylbromide, methylsulfate, napsylate, nitrate, oleate, palmoate, phosphate, polygalacturonate, stearate, succinate, sulfate, sulfo salicylate, tannate, tartrate, terphthalate, tosylate, and triethiodide.", "[0054] The active ingredient of drug have different forms for different method of administration.", "For example, when used for oral use, tablets, troches, lozenges, aqueous or oil suspensions, dispersible powders or granules, emulsions, hard or soft capsules, syrups or elixirs may be prepared.", "The method of preparing oral preparation could refer to the manufacturing process of known medicine.", "In order to provide a palatable preparation, the preparation may contain one or more agents including sweetening agents, flavoring agents, coloring agents and preserving agents.", "Tablets containing the active ingredient in admixture with non-toxic pharmaceutically acceptable excipient which are suitable for manufacture of tablets are acceptable.", "These excipients may be, for example, inert diluents, such as calcium or sodium carbonate, lactose, calcium or sodium phosphate;", "granulating and disintegrating agents, such as maize starch, or alginic acid;", "binding agents, such as starch, gelatin or acacia;", "and lubricating agents, such as magnesium stearate, stearic acid or talc.", "Tablets may be uncoated or may be coated by known techniques including microencapsulation to delay disintegration and adsorption in the gastrointestinal tract and thereby provide a sustained action over a longer period.", "For example, a time delay material such as glyceryl monostearate or glyceryl distearate alone or with a wax may be employed.", "[0055] Formulations for oral use may be in the form of hard gelatin capsules in which the active ingredient is mixed with an inert solid diluent, for example calcium phosphate or kaolin, or as soft gelatin capsules in which the active ingredient is mixed with water or an oil medium, such as peanut oil, liquid paraffin or olive oil.", "[0056] The active ingredients of the invention may be also mixed with excipients suitable for industrial manufacture to produce aqueous suspensions.", "Such excipients include suspending agent, such as sodium carboxymethylcellulose, methylcellulose, ethylcellulose, hydroxypropylcellulose, hydroxypropyl methylcellulose, sodium alginate, polyvinylpyrrolidone, gum tragacanth and gum acacia;", "dispersing or wetting agents, such as a natural phosphatide (e.g., lecithin), condensation products of alkylene oxides with fatty acids (e.g., polyoxyethylene stearate), condensation products of ethylene oxides with long chain aliphatic alcohols (e.g., heptadecyl ethyleneoxy ethanol), condensation products of ethylene oxide with a partial ester derived from fatty acids and hexitol anhydrides (e.g., polyoxyethylene sorbitan monooleate).", "The aqueous suspension may also contain one or more preservatives such as ethyl or n-propyl p-hydroxy-benzoate, coloring agents, flavoring agents and sweetening agents, such as sucrose and saccharin.", "[0057] Oil suspensions may be formulated by suspending the active ingredient in a vegetable oil (such as arachis oil, olive oil, sesame oil or coconut oil), or in a mineral oil (such as liquid paraffin).", "The oral suspensions may also contain a thickening agent (such as beeswax, hard paraffin or cetyl alcohol).", "Sweetening agents such as those set forth above, and flavoring agents may be added to provide a palatable oral preparation.", "These compositions may be preserved by the addition of an antioxidant such as ascorbic acid.", "Dispersible powders and granules of the invention is suitable for preparation of an aqueous suspension by the addition of water generally contain the the active ingredient together with a dispersing or wetting agent, suspending agent, and one or more preservatives.", "Suitable dispersing or wetting agents and suspending agents are exemplified by those disclosed above.", "Additional excipients, for example sweetening, flavoring and coloring agents, may also be present.", "[0058] The pharmaceutical compositions of the invention may also be in the form of oil-in-water emulsions.", "The oily phase may be a vegetable oil, such as olive oil and arachis oil, a mineral oil, such as liquid paraffin, or a mixture of these.", "Suitable emulsifying agents include naturally-occurring gums, such as gum acacia and gum tragacanth, naturally-occurring phosphatides, such as soybean lecithin, esters or partial esters derived from fatty acids and hexitol anhydrides, such as sorbitan monooleate, and condensation products of these partial esters with ethylene oxide, such as polyoxyethylene sorbitan monooleate.", "The emulsion may also contain sweetening and flavoring agents.", "[0059] Syrups and elixirs may be formulated with sweetening agents, such as glycerol, sorbitol or sucrose.", "Such formulations may also contain a demulcent, preservative, flavoring or coloring agent.", "[0060] The pharmaceutical compositions of the invention may be in the form of a sterile injectable preparation, such as a sterile injectable aqueous or oleaginous suspension.", "This suspension may be formulated according to the known art using those suitable dispersing or wetting agents and suspending agents which have been mentioned above.", "The sterile injectable preparation may also be a solution or suspension which is prepared by non-toxic injectable diluent or solvent, such as preparing lyophilized powder and dissolving in 1,3-butane-diol.", "The acceptable vehicles and solvents may be water, Ringer's solution and isotonic sodium chloride solution.", "In addition, sterile fixed oils may conventionally be employed as a solvent or suspending medium.", "Any bland fixed oil may be employed including synthetic mono- or di-glycerides.", "In addition, fatty acids such as oleic acid may likewise be used in the injectable preparation.", "[0061] The amount of active ingredient that may be combined with the carrier material to produce a single dosage form will vary depending upon the host treated and the particular mode of administration.", "For example, a time-release formulation intended for oral administration to humans may contain 20 to 2000 μmol (approximately 10 to 1000 mg) active ingredient and appropriate carrier material which may vary from about 5 to about 95% of the total compositions.", "It is preferred that the pharmaceutical composition be prepared which provides easily measurable amounts for administration.", "For example, an aqueous solution intended for intravenous infusion should contain from about 0.05 to about 50 μmol (approximately 0.025 to 25 mg) of the active ingredient per milliliter of solution in order that infusion of a suitable volume at a rate of about 30 mL/hr can occur.", "[0062] As noted above, oral preparation may be presented as discrete units such as capsules, cachets or tablets, each containing a predetermined amount of the active ingredient;", "as a powder or granules;", "as a solution or suspension in an aqueous or non-aqueous liquid;", "or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion.", "The active ingredient may also be administered as a bolus, electuary or paste.", "[0063] A tablet may be made by compression or molding, optionally with one or more accessory ingredients.", "Compressed tablets may be prepared by compressing in a suitable machine the active ingredient in a free flowing form such as a powder or granules, optionally mixed with a binder (e.g., povidone, gelatin, hydroxypropylmethyl cellulose), lubricant, inert diluent, preservative, disintegrant (e.g., sodium starch glycolate, cross-linked povidone, cross-linked sodium carboxymethyl cellulose) surface active or dispersing agent.", "Molded tablets may be made by molding in a suitable machine a mixture of the powdered compound moistened with an inert liquid diluent.", "The tablets may optionally be coated or scored in preparing so as to provide slow or controlled release of the active ingredient therein using, for example, hydroxypropyl methylcellulose in varying proportions to provide the desired release profile.", "Tablets may optionally be provided with an enteric coating, to provide release in parts of the gut other than the stomach.", "This is particularly advantageous with the compounds of Formula I when such compounds are susceptible to acid hydrolysis.", "[0064] Formulations suitable for topical administration in the mouth include pastille comprising the active ingredient in a flavored base, usually sucrose, acacia or tragacanth;", "pastilles comprising the active ingredient in an inert base such as gelatin, glycerin, sucrose and acacia;", "and mouthwashes comprising the active ingredient in a suitable liquid carrier.", "[0065] Formulations for rectal administration may be presented as a suppository comprising the active compound in a suitable base comprising such as cocoa, butter or a salicylate.", "Formulations suitable for vaginal administration may add the active ingredient and known suitable carriers in pessaries, tampons, creams, gels, pastes, foams or spray.", "[0066] Formulations suitable for parenteral administration include aqueous and non-aqueous isotonic sterile injection solutions which may contain antioxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient;", "and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents.", "The formulations may be presented in unit-dose or multi-dose sealed containers, for example, ampoules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use.", "[0067] Injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the kind previously described.", "[0068] Formulations suitable for parenteral administration may be administered in a continuous infusion manner via an indwelling pump or via a hospital bag.", "The infusions may be done through a Hickman or PICC or any other means suitable for parenterally and i.v. [0069] Preferred unit dosage formulations contains a daily dose or unit, each dose, and daily frequency.", "[0070] It will be understood, however, that the specific dose level for any particular patient will depend on a variety of factors including the activity of the specific compound employed;", "the age, body weight, general health, sex and diet of the individual being treated;", "the time and route of administration;", "the rate of excretion;", "other drugs which have previously been administered;", "and the severity of the particular disease undergoing therapy, as is well understood by those skilled in the art.", "Synthesis of the Compounds of Formula I and Formula II [0071] The compounds in this invention may be prepared by the processes described in the following discussions, as well as relevant published literature procedures that are used by those skilled in the art.", "It should be understood that the following discussions are provided solely for the purpose of illustration and do not limit the invention which is defined by the claims.", "Typically the synthesis of the compound of Formula I includes the following general five steps (listed in reversed order): (1) Preparation of a prodrug;", "(2) Deprotection of a phosphonate ester;", "(3) Modifications of an existing quinoline;", "(4) Construction of a quinoline;", "and (5) Preparation of key precursors.", "The compounds of Formula II could be synthesized by the compounds of Formula I reacting with suitable groups.", "Protection and deprotection in the Schemes may be carried out according to the procedures generally known in the art (e.g., “Protecting Groups in Organic Synthesis,” 3rd Edition, Wiley, 1999).", "[0072] All stereoisomers of the compounds of the present invention are contemplated, either in admixture or in pure or substantially pure form.", "The compounds of the present invention can have stereogenic centers at the phosphorus atom and at any of the carbons including any of the R substituents.", "Consequently, compounds of Formula I can exist in enantiomeric or diastereomeric forms or in mixtures thereof.", "The processes for preparation can utilize racemates, enantiomers or diastereomers as starting materials.", "When enantiomeric or diastereomeric products are prepared, they can be separated by conventional methods.", "For example, chromatography or fractional crystallization can be used to separate diastereomeric mixtures, while derivatives of enantiomeric isomers can be separated via chromatography.", "1) Preparation of a Prodrug [0073] Prodrugs can be introduced at different stages of the synthesis.", "Most often these prodrugs are introduced at the later stage of a synthesis due to the lability of various prodrugs, while prodrugs could also be introduced at an early stage of the synthesis due to other considerations.", "[0074] The compounds of Formula I could be phosphonic acids wherein both R 1 and R 2 are H, and also be in a suitably protected form.", "Phosphonic acids can be alkylated with electrophiles such as alkyl halides and alkyl sulfonates under nucleophilic substitution conditions to give phosphonate esters.", "For example, compounds of Formula I wherein Wand R 2 are acyloxyalkyl groups can be prepared by direct alkylation of compounds of Formula I wherein both R 1 and R 2 are H with an appropriate acyloxyalkyl halide (e.g. Cl, Br, I;", "Phosphorus Sulfur 1990, 54, 143 ;", "Synthesis 1988, 62) in the presence of a suitable base (e.g. pyridine, TEA, diisopropylethylamine) in suitable solvents such as DMF ( J. Med.", "Chem.", "1994, 37, 1875).", "The carboxylate component of these acyloxyalkyl halides includes but is not limited to acetate, propionate, isobutyrate, pivalate, benzoate, carbonate and other carboxylates.", "[0075] Reactive dichlorophosphonates can be generated from the corresponding phosphonic acids with a chlorinating agent (e.g. thionyl chloride, J. Med.", "Chem.", "1994, 1857;", "oxalyl chloride, Tetrahedron Lett.", "1990, 31, 3261;", "phosphorous pentachloride, Synthesis 1974, 490).", "Alternatively, a dichlorophosphonate can be generated from its corresponding disilyl phosphonate esters ( Synth.", "Commu.", "1987, 17, 1071) and dialkyl phosphonate esters ( Tetrahedron Lett.", "1983, 24, 4405 ;", "Bull.", "Soc.", "Chim.", "1993, 130, 485).", "Cyclic phosphonate esters of substituted 1,3-propane diols can be synthesized by either reactions of the corresponding dichlorophosphonate with a substituted 1,3-propanediol or coupling reactions using suitable coupling reagents (e.g. DCC, EDCI, PyBOP;", "Synthesis 1988, 62).", "[0076] Alternatively, these cyclic phosphonate esters of substituted 1,3-propane diols are prepared from phosphonic acids by coupling with diols under Mitsunobu reaction conditions ( Synthesis 1 (1981);", "J. Org.", "Chem.", "52:6331 (1992)), and other acid coupling reagents including, but not limited to, carbodiimides ( Collect.", "Czech.", "Chem.", "Commun.", "59:1853 (1994);", "Bioorg.", "Med.", "Chem.", "Lett.", "2:145 (1992);", "Tetrahedron Lett.", "29:1189 (1988)), and PyBOP ( Tetrahedron Lett.", "34, 6743 (1993)).", "[0077] One aspect of the present invention provides methods to synthesize and isolate single isomers of prodrugs of phosphonic acids of Formula I. Because phosphorus is a stereogenic atom, formation of a prodrug with a racemic substituted-1,3-propane-diol will produce a mixture of isomers.", "For example, formation of a prodrug with a racemic 1-(Y)-substituted-1,3-propane diol gives a racemic mixture of cis-prodrugs and a racemic mixture of trans-prodrugs.", "In another aspect, the use of the enantioenriched substituted-1,3-propane diol with the R-configuration gives enantioenriched R-cis- and R-trans-prodrugs.", "These compounds can be separated by a combination of column chromatography and/or fractional crystallization.", "[0078] Another prodrug group can be introduced for expected properties.", "Compounds of Formula I (X=OH) can be connected with different protecting groups on the O atom of N atom of the hydroxypyridine ring.", "For example, compounds of formula I (R 3 is carboxyl group) could be prepared from compound of formula I (R 3 is H) with appropriate carboxyl halide under suitable reaction conditions ( J. Org.", "Chem.", "1989, 54, 166);", "compounds of formula I (X is Cl) could be generated from compound of formula I (X is OH) with different chlorinating reagent (for example: POCl 3 , J. Org.", "Chem.", "1950, 15, 1224;", "CCl 3 CN, Tetrahedron Lett.", "2012, 53, 674) under appropriate conditions.", "2) Deprotection of a Phosphonate Ester [0079] Compounds of Formula I wherein R 1 is H may be prepared from phosphonate esters using known phosphate and phosphonate ester cleavage conditions.", "Silyl halides are generally used to cleave various phosphonate esters, and subsequent mild hydrolysis of the resulting silyl phosphonate esters give the desired phosphonic acids.", "When required, acid scavengers (e.g. 1,1,1,3,3,3-hexamethyldisilazane, 2,6-lutidine) can be used for the synthesis of acid labile compounds.", "Such silyl halides include chlorotrimethylsilane J. Org.", "Chem.", ", 1963, 28: 2975), and bromotrimethylsilane ( Tetrahedron Lett.", ", 1977, 155), and iodotrimethylsilane ( J. Chem.", "Soc.", ", Chem.", "Commun.", ", 1978, 870).", "Alternately, phosphonate esters can be cleaved under strong acidic conditions (e.g. HBr or HCl: Moffatt, et al, U.S. Pat. No. 3,524,846, 1970).", "These esters can also be cleaved via dichlorophosphonates, prepared by treating the esters with halogenating agents (e.g. phosphorus pentachloride, thionyl chloride, BBr 3 : Pelchowicz et al.", ", J. Chem.", "Soc.", ", 1961, 238) followed by aqueous hydrolysis to give phosphonic acids.", "Aryl and benzyl phosphonate esters can be cleaved under hydrogenolysis conditions (Lejczak, et al.", ", Synthesis, 1982, 412;", "Elliott, et al.", ", J. Med.", "Chem.", ", 1985, 28: 1208;", "Baddiley, et al.", ", Nature, 1953, 171: 76) or metal reduction conditions (Shafer, et al.", ", J. Am.", "Chem.", "Soc.", ", 1977, 99: 5118).", "Electrochemical (Shono, et al.", ", J. Org.", "Chem.", ", 1979, 44: 4508) and pyrolysis (Gupta, et al.", ", Synth.", "Commun.", ", 1980, 10: 299) conditions have also been used to cleave various phosphonate esters.", "(3) Synthesis of Phosphorus-Containing Phenantholines [0080] Construction of the phenantholine core could be carried out using well-established literature methods.", "For example, a thermal cyclization strategy is illustrated in the following scheme.", "[0000] [0081] Treatment of arylamine 1 with sodium 3-nitrobenzenesulfonate, sulfuric acid and glycerol provided quinoline 2.", "Bromination of quinoline 2 using NBS in acetic acid provided compound 3 which was reduced using iron to give compound 4.", "Phosphonylation of compound 4 gave phosphonate 5 which was treated with compound 17 and followed by a thermal cyclization reaction to provide phenantholine 7 wherein R is H (compounds of formula I wherein X is OH, R 1 =R 2 =Et).", "Treatment of compound 7 with sodium hydroxide provided compound 8 wherein R is H (compounds of formula I wherein X is OH, R 1 =H, R 2 =Et);", "on the other hand, treatment of compound 7 with 48% HBr provided compound 9 wherein R is H (compounds of formula I wherein X is OH, R 1 =R 2 =H).", "In some cases, the desired substituents are not compatible with subsequent reactions, and therefore modifications of an existing phenantholine are envisioned using conventional chemistry (Larock, Comprehensive organic transformations , VCH, New York, 1989;", "Trost, Comprehensive organic synthesis ;", "Pergamon press, New York, 1991).", "[0082] Prodrugs often are introduced at the later stage of a synthesis, while some prodrugs could also be introduced at an early stage of the synthesis due to other considerations.", "For example, the cyclic phosphonate diester prodrugs could be prepared as illustrated in the following scheme.", "[0000] [0083] Phosphonylation of compound 3 gave phosphonate 10 which was deprotected using 48% HBr to give phosphonic acid 11.", "Treatment of compound 11 with POCl 3 gave the reactive dichlorophosphonates 12 which was immediately coupled with diol 20 ( J. Am.", "Chem.", "Soc.", "2004, 5154) to give compound 13.", "Reduction of the nitro group in compound 13 followed by reaction with compound 17 and then thermal ring closure to give phenantholine 16 wherein R is H (compounds of formula I wherein X is OH, R 1 and R 2 together form a cyclic group).", "[0084] Another prodrug group can be introduced for expected properties.", "For example, compound 16c reacted with chlorophosphate under suitable base (for example: Et 3 N) and catalyst (for example: 4-dimethylaminopyridine) in suitable solvent (for example: CH 2 Cl 2 ) to yield phosphate 21.", "The deprotection of diethyl phosphate can be achieved by using common phosphate deprotecting reagent.", "For example, deprotection of phosphate 21 by trimethylsilyl bromide gave phosphoric acid 22, which can be converted to desired salt.", "For example, compound 22 mixed with sodium bicarbonate in water and methanol could give disodium salt 23.", "[0000] [0085] In another example, other types of prodrugs could be formed for different expected properties.", "For example, di-t-butylchloromethyl phosphate reacted with phenanthroline 16c under suitable base (for example: K 2 CO 3 ) in suitable solvent (for example: DMSO) to afford phosphate ester 24 and 25.", "Common t-butyl deprotecting agent could be used to remove di-t-butyl groups.", "For example, deprotection of 24 and 25 with trifluoroacetic acid in dichloromethane gave phosphoric acid 26 and 27, respectively.", "Compound 26 and 27 could be further converted to desired salts.", "[0000] EXAMPLES [0086] The compounds used in this invention and their preparation can be understood further by the Examples.", "These Examples should not however be construed as specifically limiting the invention, and variations of the compounds, now known or later developed, are considered to fall within the scope of the present invention as hereinafter claimed.", "Example 1 Syntheses of Compounds The preparation of 8-nitroquinoline (2c) [0087] [0088] A mixture was prepared to which 47 g of H 2 SO 4 , 20 ml of H 2 O, 23.4 g (0.104 mol) of sodium 3-nitrobenzene sulfonate, and 22 ml of glycerol were added in that order.", "It was warmed gently until forming a solution, and 11 g 2-nitroaniline 1c (0.08 mol) was added in portions.", "The mixture was refluxed for 5 h. After cooling to room temperature, the mixture was poured into 600 ml H 2 O under ice bath, adjusted to pH 6-7 with aqueous ammonia, and suction-filtered.", "The cake was dried and purified with chromatography (EA:PE=1:5).", "A yellow solid 2c 6.177 g was given in 44%.", "[0089] 1H NMR (300 MHz, CDCl3) δ 9.09 (dd, J=1.8 Hz, 4.5 Hz, 1H), 8.28 (dd, J=1.8 Hz, 8.4 Hz, 1H), 8.05 (d, J=9 Hz, 2H), 7.66-7.55 (m, 2H).", "The preparation of 3-bromo-8-nitroquinoline (3c) [0090] [0091] 8-nitroquinoline 2c 6.177 g (35.5 mmol) was added to 110 ml of acetic acid, and then 6.651 g NBS (35.5 mmol) was added.", "The mixture reacted at 50° C. for 2 h. The reaction mixture was cooled and poured into 600 ml H 2 O, and suction-filtered.", "The cake was dried and purified with chromatography (EA:PE=1:15) to give yellow solid 3c 2.625 g in 29%.", "[0092] 1H NMR (300 MHz, CDCl3) δ9.06 (d, J=2.1 Hz, 1H), 8.44 (d, J=2.4 Hz, 1H), 8.06 (d, J=7.5 Hz, 1H), 7.98 (d, J=8.1 Hz, 1H), 7.67 (t, J=7.8 Hz, 1H).", "The preparation of 3-bromoquinolin-8-amine (4c) [0093] [0094] Compound 3c (13.0 g, 51.6 mmol) was added to EtOH (150 mL), and then iron powder (11.6 g, 206.4 mmol), NH 4 Cl (11.0 g, 206.4 mmol) was added.", "The resulting was refluxed for overnight.", "The reaction mixture was cooled and filtered through celite.", "The filtrate was evaporated to dryness and purified with chromatography (EA:PE=1:5).", "A yellow solid 4c 8.23 g was given in 72%.", "[0095] 1H NMR (300 MHz, CDCl3) δ 8.72 (d, J=2.1 Hz 1H), 8.21 (d, J=2.1 Hz, 1H), 7.35 (t, J=7.8 Hz, 1H), 7.05 (dd, J=1.2 Hz, 8.1 Hz, 1H), 7.61 (dd, J=1.2 Hz, 7.5 Hz, 1H), 4.98 (s, 2H).", "The preparation of Diethyl 8-aminoquinolin-3-yl phosphonate (5c) [0096] [0097] Compound 4c (4.0 g, 17.9 mmol) was added to EtOH (53 mL) under N 2 , and then HPO(OEt) 2 (3.0 mL, 23.3 mmol), TEA (3.7 mL, 26.9 mmol), Ph 3 P (1.27 g, 4.8 mmol) and Pd(OAc) 2 (0.8 g, 3.58 mmol) was added.", "The resulting mixture was refluxed for overnight.", "The reaction mixture was cooled to room temperature and charged with H 2 O (100 mL), extracted with EA.", "The organic layers was merged, washed with brine, dried over anhydrous Na 2 SO 4 , concentrated, and purified with chromatography (EA:PE=1:1).", "A yellow oil 5c 1.4 g was given in 25%.", "[0098] 1H NMR (300 MHz, CDCl3) δ 8.98 (dd, J=1.8 Hz, 4.2 Hz, 1H), 8.59 (dd, J=2.1 Hz, 15.3 Hz, 1H), 7.38 (d, J=7.8 Hz, 1H), 7.21 (d, J=7.5 Hz, 1H), 7.01 (t, J=7.5 Hz, 1H), 4.20-4.07 (m, 4H), 1.35 (t, J=6.9 Hz, 6H) The preparation of Diethyl 8-((2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)methylamino)quinolin-3-yl phosphonate (6c) [0099] [0100] Compound 5c (1.4 g, 5 mmol) was added to EtOH (40 mL) under N 2 , and then compound 17 was added.", "The reaction mixture was refluxed for overnight.", "The reaction mixture was cooled to room temperature, evaporated the solvent and purified with chromatography (EA:PE=1:1).", "A yellow solid 6c 1.125 g was given in 52%.", "[0101] 1H NMR (300 MHz, CDCl3) δ 12.8 (d, J=15 Hz, 1H), 9.20 (dd, J=1.8 Hz, 4.2 Hz, 1H), 8.91 (d, J=14.7 Hz, 1H), 8.74 (dd, J=1.8 Hz, 15.3 Hz 1H), 7.80-7.76 (m, 2H), 7.67 (t, J=7.8 Hz, 1H), 4.30-4.09 (m, 4H), 1.81 (s, 6H), 1.35 (t, J=6.9 Hz, 6H).", "The preparation of Diethyl 7-hydroxy-1,10-phenanthrolin-3-yl phosphonate (7c) [0102] [0103] Diphenyl ether was heated to boiling, compound 6c (1.1 g, 2.5 mmol) was added to rapidly.", "The resulting mixture was stirred for 2 min at reflux.", "The mixture was cooled to 100° C., poured into PE (640 mL) under stirring, suction-filtered.", "The cake was purified with chromatography (MeOH:DCM=1:20).", "A yellow solid 7c 650 mg was given in 77%.", "[0104] 1H NMR (300 MHz, CDCl3) δ 10.8 (s, 1H), 9.31 (dd, J=1.8 Hz, 5.1 Hz, 1H), 8.72 (dd, J=1.8 Hz, 14.7 Hz, 1H), 8.49 (d, J=8.7 Hz, 1H), 7.94 (d, J=7.5 Hz, 1H), 7.71 (d, J=9 Hz, 1H), 6.62 (d, J=7.5 Hz, 1H), 4.35-4.14 (m, 4H), 1.39 (t, J=6.9 Hz, 6H).", "The preparation of 7-hydroxy-1,10-phenanthrolin-3-yl phosphonic acid (9c) [0105] [0106] Compound 7c (650 mg) was added to 48% HBr aq.", "The resulting mixture was refluxed for overnight.", "The reaction mixture was cooled to room temperature, evaporated the solvent, stirred with a small amount of water, suction-filtered, and dried.", "A gray solid 9c 513 mg was given in 95%.", "[0107] 1H NMR (300 MHz, D2O) δ 8.99 (dd, J=4.5 Hz, 1.8 Hz, 1H), 8.30 (dd, J=12.6 Hz, 1.8 Hz, 1H), 7.62□ (d, J=6.9 Hz, 1H), 740 (d, J=8.7 Hz, 1H), 7.26 (d, J=8.7 Hz, 1H), 6.19 (d, J=7.2 Hz, 1H).", "The preparation of Diethyl 8-nitroquinolin-3-yl phosphonate (10c) [0108] [0109] Compound 3c (30 g), KOAc (23.4 g), HPO(OEt) 2 (18.4 mL), toluene (300 mL) and Pd(dppf) 2 Cl 2 .", "CH 2 Cl 2 (1 g) were added to flask in sequence under N 2 .", "The resulting mixture was refluxed for 3 hours, diluted with EtOAc, filtered through Silica gel, and concentrated to afford 10c 46 g. [0110] 1H NMR (300 MHz, CDCl3) δ 9.28 (dd, J=1.8 Hz, 4.2 Hz, 1H), 8.82 (dd, J=1.8 Hz, 15 Hz, 1H), 8.16 (t, J=6 Hz, 2H), 7.21 (d, J=7.5 Hz, 1H), 7.74 (t, J=8.1 Hz, 1H), 4.33-4.11 (m, 4H), 1.37 (t, J=6.9 Hz, 6H).", "The preparation of 8-nitroquinolin-3-yl phosphonic acid (11c) [0111] [0112] Compound 10c (44.5 g) was added to 48% HBraq (230 mL).", "The resulting mixture was refluxed for 4 hours.", "The mixture was cooled, evaporated to dryness.", "The solid was washed with EtOH/EtOAc for 2 hours, and suction-filtered.", "A yellow solid 11c 31.5 g was given.", "[0113] 1H NMR (300 MHz, D20) δ 9.18 (dd, J=□1.8 Hz, 6 Hz, 1H), 8.98 (dd, J=1.8 Hz, 13.2 Hz, 1H), 8.54 (d, J=7.8 Hz, 1H), 8.36 (d, J=8.4 Hz, 1H), 7.81 (t, J=7.8 Hz, 1H).", "[0114] The preparation of 8-nitroquinolin-3-yl phosphonic dichloride (12c) [0000] [0115] Compound 11c (50.3 g) was added to dichloroethane (650 mL), and then DMF (3.6 mL) was added.", "Then (COCl) 2 (42 mL) was added dropwise under ice bath.", "After the addition was complete, the resulting mixture was refluxed for overnight.", "The mixture was cooled, and evaporated to dryness to yield 12c which was immediately used in the subsequent reaction.", "The preparation of (4S)-4-(3-chlorophenyl)-2-(8-nitroquinolin-3-yl)-1,3,2-dioxaphosphinan-2-one (13c) [0116] [0117] (S)-1-(3-chlorophenyl)propane-1,3-diol (36.95 g) 20 was added to CH 2 Cl 2 (540 mL).", "Then TiCl 4 was added (22 mL) dropwise under −78° C. The mixture was stirred for 5 minutes, and then stirred for 5 minutes under ice bath.", "TEA (110 mL) was added to the mixture.", "The resulting mixture was added dropwise to the solution of compound 12c in dichloromethane.", "After the addition was complete, the resulting mixture reacted at room temperature for overnight.", "The reaction mixture was diluted with CH 2 Cl 2 (700 mL), charged with 10% tartaric acid (210 mL), and stirred for 2 minutes.", "The mixture was filtered through celite, extracted with CH 2 Cl 2 .", "The organic layer was dried over Na 2 SO 4 , and the solvent removed.", "The residue was recrystallized twice from CH 3 CN.", "A yellow solid 13c 35.5 g was given in 44%.", "m/z: 405.1 [M+1];", "The preparation of (4S)-4-(3-chlorophenyl)-2-(8-aminoquinolin-3-yl)-1,3,2-dioxaphosphinan-2-one (14c) [0118] [0119] Compound 13c (62.9 g) was added to EtOH (160 mL) and AcOH (160 mL).", "Then Fe (43.6 g) was added.", "The resulting mixture reacted at 40° C. for 10 minutes, cooled, adjusted to pH 6 with sat.", "NaHCO 3 solution, extracted with CH 2 Cl 2 .", "The organic layer was dried over Na 2 SO 4 , and evaporated.", "A yellow solid 14c 50 g was given in 86%.", "m/z: 375.0 [M+1];", "The preparation of (4S)-4-(3-chlorophenyl)-2-(8-((2,2-dimethyl-1,3-dioxane-4,6-dione)-5-methylene)aminoquinolin-3-yl)-1,3,2-dioxaphosphinan-2-one (15c) [0120] [0121] Compound 14c (49 g) was added to EtOH (320 mL).", "then 5-(ethoxymethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione 17 (31.4 g) was added.", "The resulting mixture was refluxed for 2 hours, cooled, and suction-filtered.", "A yellow solid 15c 60 g was given in 87%.", "m/z: 529.0 [M+1], 471.0 was found.", "The preparation of (4S)-4-(3-chlorophenyl)-2-(7-hydroxy-1,10-phenanthrolin-3-yl)-1,3,2-dioxaphosphinan-2-one (16c) [0122] [0123] Diphenyl ether was heated to boiling, compound 15c (3 g) was added to rapidly.", "The resulting mixture was refluxed for 50 s. The mixture was cooled to 100° C., poured into petroleum ether, and suction-filtered.", "The cake was purified with chromatography (DCM:MeOH=30:1).", "A yellow solid 16c 1.676 g was given in 70%.", "[0124] 1H NMR (300 MHz, DMSO) δ 12.53 (s, 1H), 9.34 (dd, J=2.1 Hz, 5.1 Hz, 1H), 9.15 (dd, J=1.8 Hz, 15.3 Hz, 1H), 8.27 (d, J=8.7 Hz, 1H), 8.12-7.98 (m, 2H), 7.56 (s, 1H), 7.47-7.43 (m, 3H), 6.36 (d, J=7.2 Hz, 1H), 5.96 (d, J=11.1 Hz, 1H), 4.88-4.76 (m, 1H), 4.65-4.55 (m, 1H), 2.68-2.54 (m, 1H), 2.34-2.22 (m, 1H).", "The preparation of methyl 3-(3-chlorophenyl)-3-oxopropanoate (18) [0125] [0126] Potassium t-butoxide (15 g) was added to THF (50 mL) under nitrogen.", "The mixture was stirred at room temperature for 15 minutes.", "1-(3-chlorophenyl) ethanone (10 g) and dimethyl carbonate (11 mL) was added slowly to the flask under ice bath.", "The mixture was stirred at room temperature for 1.5 hour.", "The reaction mixture was charged with water (40 mL) and concentrated hydrochloric acid (1.3 ml) and stirred for 15 minutes.", "[0127] The organic layers were separated and the aqueous phase was extracted again with toluene.", "The combined organic extracts were washed with saturated brine, dried with NaSO 4 , filtered and evaporated to dryness.", "A brown oil 18 13.22 g was given in 96%.", "The preparation of (3S)-methyl 3-(3-chlorophenyl)-3-hydroxypropanoate (19) [0128] [0129] The triethylamine (5.38 g) was added dropwise slowly to formic acid (9.8 g) under nitrogen under ice bath.", "After the addition was complete, the mixture was stirred for 20 minutes and then reacted at room temperature for 1 hour.", "Compound 18 (11.3 g), DMF (45 mL) and (S,S)-Ts-DPEN-Ru—Cl-(p-cymene) (68 mg) were added to the flask.", "The resulting mixture reacted at 60° C. for overnight, was cooled to room temperature, charged with water (100 mL), extracted with EA.", "The organic layer was washed with brine, dried over anhydrous Na 2 SO 4 , filtered, evaporated to dryness, and purified with chromatography (EA:PE=1:10).", "A jacinth oil 10.434 g was given in 91%.", "[0130] 1H NMR (300 MHz, CDCl3) δ 7.45 (s, 1H), 7.37-7.27 (m, 3H), 5.16 (t, J=6.9 Hz, 1H), 3.78 (s, 3H), 2.78 (d, J=1.8 Hz, 1H), 2.76 (s, 1H).", "The preparation of (1S)-1-(3-chlorophenyl)propane-1,3-diol (20) [0131] [0132] Sodium borohydride (1.84 g) and water (0.62 mL) were added to 1-butanol (37.5 mL), and then the solution of compound 19 (10.4 g) in 1-butanol (3.8 mL) was added dropwise to under ice bath.", "After addition was complete, the mixture was stirred for 0.5 h, and reacted at 90° C. for 4 h. The reaction mixture was cooled to room temperature, charged with aqueous potassium carbonate solution (10%, 23 mL), and stirred for 10 min.", "The organic layers were separated, washed with aqueous potassium carbonate solution (10 wt/vol %, 8 mL) and brine (8 mL), dried over anhydrous Na 2 SO 4 , filtered, evaporated to dryness, and purified with chromatography (DCM:CH 3 OH=30:1).", "A yellow oil 20 7.75 g was given in 85.5%.", "[0133] 1H NMR (300 MHz, CDCl3) δ 7.36 (s, 1H), 7.30-7.20 (m, 3H), 4.92 (q, J=4.5□Hz, 7.8 Hz, 1H), 3.90-3.79 (m, 2H), 2.82 (s, 2H), 2.03-1.85 (m, 2H).", "The preparation of 3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-yl phosphoric acid (22) [0134] [0135] Compound 16c (2 g) was dissolved in dichloromethane (100 mL).", "Triethylamine (2 mL) and 4-dimethylamino pyridine (57 mg) were added to the reaction mixture.", "The reaction mixture was putted under ice bath.", "Diethyl chlorophosphate (2 mL) in dichloromethane (20 mL) was added dropwise slowly to the reaction mixture.", "The mixture was allowed to react for one hour under ice bath and then 2 hours at room temperature.", "The reaction mixture was poured into saturated brine (200 mL).", "The organic layer was separated and the aqueous layer was extracted with dichloromethane.", "The organic layers were combined, dried over anhydrous sodium sulfate, rotary evaporated to dryness, and purified with chromatography (DCM:CH 3 OH=100:1) to yield 21 1.7 g. 21 (1.7 g) was dissolved in DCM (2 mL).", "Trimethylsilyl bromide (4 mL) was added to the mixture in one time under ice bath.", "After reacted 1 hr under ice bath, diethyl ether (50 mL) was added to the reaction mixture.", "The resulting mixture was filtered.", "The cake was collected, dissolved in methanol (20 mL), and stirred for 10 minutes.", "The reaction mixture was rotary evaporated to dryness and purified with chromatography (DCM:CH 3 OH:CH 3 COOH=20:1:0.05 DCM:H 3 OH=4:1).", "A white solid 22 600 mg was given in 25% yield.", "[0136] m/z: 507.0 [M+1];", "[0137] □1H NMR (300 MHz, dmso) δ 13.84 (m, 1H), □9.27 (dd, J=4.8, 1.8 Hz, 1H), 8.99 (dd, J=14.3, 1.8 Hz, 1H), 8.39 (d, J=7.1 Hz, 1H), 8.30 (d, J=8.9 Hz, 1H), 8.13 (d, J=9.0 Hz, 1H), 7.50 (s, 1H), 7.45-7.38 (m, 1H), 7.35-7.25 (m, 2H), 6.85 (d, J=7.1 Hz, 1H), 5.35 (dd, J=9.0, 5.9 Hz, 1H), 4.11-3.98 (m, 2H), 2.68-2.55 (m, 1H), 2.50-2.34 (m, 1H).", "The preparation of Disodium 3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-yl phosphate (23) [0138] [0139] Compound 22 (500 mg) was suspended to methanol (10 mL), 1N NaHCO 3 solution (2 mL) was added to the mixture slowly at room temperature.", "The reaction mixture was allowed to stir for 20 minutes, and evaporated to dryness.", "A white solid 23 540 mg was given in 100% yield.", "[0140] m/z: 550.0 [M+1], found 507;", "[0141] 1H NMR (300 MHz, dmso) δ 9.27 (dd, J=4.8, 1.8 Hz, 1H), 8.99 (dd, J=14.3, 1.8 Hz, 1H), 8.39 (d, J=7.1 Hz, 1H), 8.30 (d, J=8.9 Hz, 1H), 8.13 (d, J=9.0 Hz, 1H), 7.50 (s, 1H), 7.45-7.38 (m, 1H), 7.35-7.25 (m, 2H), 6.85 (d, J=7.1 Hz, 1H), 5.35 (dd, J=9.0, 5.9 Hz, 1H), 4.11-3.98 (m, 2H), 2.68-2.55 (m, 1H), 2.50-2.34 (m, 1H).", "The preparation of di-t-butyl (3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-oxy)-7-methyl phosphate (24) and di-t-butyl (3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-one)-10(7H)-methyl phosphate (25) [0142] [0143] Compound 16c (200 mg, 0.47 mmol) was dissolved in DMSO (2 mL).", "Potassium carbonate (195 mg, 1.41 mmol) was added to the reaction mixture.", "The resulting mixture was stirred for 15 minutes under 30° C. Di-t-butyl chloromethyl phosphate (146 mg, 0.56 mmol) was added to the reaction mixture and the resulting mixture reacted at 30° C. for overnight.", "The reaction mixture was poured into saturated brine (20 mL).", "The organic layer was separated and the aqueous layer extracted with dichloromethane.", "The organic layers were combined, dried over sodium sulfate, rotary evaporated to dryness and purified with chromatography (EA) to yield intermediate 24 and 25.", "[0144] m/z: 649.2[M+1];", "[0145] Compound 24: [0146] 1H NMR (300 MHz, dmso) δ 9.48 (dd, J=4.9, 1.9 Hz, 1H), 9.14 (dd, J=15.4, 1.9 Hz, 1H), 9.10 (d, J=5.3 Hz, 1H), 8.31 (d, J=9.1 Hz, 1H), 7.63-7.58 (m, 2H), 7.55-7.41 (m, 3H), 6.11-5.91 (m, 3H), 4.92-4.75 (m, 1H), 4.71-4.53 (m, 1H), 2.73-2.55 (m, 1H), 2.36-2.19 (m, 1H), 1.37 (s, 18H) [0147] 13C NMR (75 MHz, dmso) δ 158.59, 151.37, 150.71, 150.54, 147.15, 146.18, 142.12, 142.01, 141.71, 133.29, 130.57, 128.41, 126.26, 125.79, 124.59, 121.53, 120.83, 106.97, 87.59, 82.98, 77.56, 66.24, 33.30, 29.38 [0148] Compound 25: [0149] 1H NMR (300 MHz, dmso) δ 9.39 (dd, J=4.6, 2.1 Hz, 1H), 9.19 (dd, J=15.6, 2.0 Hz, 1H), 8.43 (d, J=8.7 Hz, 1H), 8.22 (d, J=8.1 Hz, 1H), 8.18 (d, J=8.4 Hz, 1H), 7.58 (s, 1H), 7.50-7.44 (m, 3H), 7.18-6.99 (m, 2H), 6.49 (d, J=7.9 Hz, 1H), 5.98 (d, J=11.2 Hz, 1H), 4.93-4.72 (m, 1H), 4.69-4.49 (m, 1H), 2.72-2.52 (m, 1H), 2.34-2.19 (m, 1H), 1.21 (s, 9H), 1.19 (s, 9H).", "[0150] 13C NMR (75 MHz, dmso) δ 176.22, □148.52, 147.50, 142.91, 141.99, 141.88, 136.23, 133.28, 130.54, 129.08, 128.91, 128.46, 125.72, 125.00, 124.60, 124.08, 121.52, 112.53, 82.30, 80.38, 77.54, 66.52, 33.21, 29.16.", "(3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-oxy)-7-methyl phosphoric acid (26) [0151] [0152] Compound 24 (50 mg, 0.08 mmol) was dissolved in dichloromethane (3 mL).", "TFA (1 mL) was added to the mixture at room temperature.", "The reaction mixture was stirred for 30 minutes at room temperature.", "The reaction mixture was evaporated to dryness.", "Methanol (1 mL) was added to the residue, and the mixture was suction-filtered to afford compound 26.", "[0153] 1H NMR (300 MHz, dmso) δ 9.46 (dd, J=05.0, 1.8 Hz, 1H), 9.23-9.05 (m, 2H), 8.37-8.21 (m, 2H), 7.68 (d, J=5.6 Hz, 1H), 7.56 (s, 1H), 7.51-7.36 (m, 3H), 6.12-5.90 (m, 3H), 4.90-4.74 (m, 1H), 4.71-4.50 (m, 1H), 2.71-2.54 (m, 1H), 2.33-2.21 (m, 1H) The preparation of (3-(4S-4-(3-chlorophenyl)-1,3,2-dioxaphosphinan-2-one-2-yl)-1,10-phenanthrolin-7-one)-10(7H)-methyl phosphoric acid (27) [0154] [0155] Compound 25 (50 mg, 0.08 mmol) was dissolved in dichloromethane (3 mL).", "TFA (1 mL) was added to the mixture at room temperature.", "The reaction mixture was stirred for 30 minutes at room temperature.", "The reaction mixture was evaporated to dryness.", "Methanol (1 mL) was added to the residue, and the mixture was suction-filtered to afford compound 27.", "[0156] 1H NMR (300 MHz, dmso) δ 9.38 (dd, J=4.5, 2.0 Hz, 1H), 9.13 (dd, J=15.6, 2.0 Hz, 1H), 8.40 (d, J=8.7 Hz, 1H), 8.19 (d, J=8.3 Hz, 1H), 8.13 (d, J=8.7 Hz, 1H), 7.58 (s, 1H), 7.54-7.35 (m, 3H), 7.04 (t, J=9.9 Hz, 1H), 6.91 (t, J=9.8 Hz, 1H), 6.43 (d, J=7.8 Hz, 1H), 5.95 (d, J=10.8 Hz, 1H), 4.88-4.76 (m, 1H), 4.69-4.45 (m, 1H), 2.74-2.56 (m, 1H), 2.31-2.22 (m, 1H).", "Example 2 Expression and Purification of P4H [0157] Human recombinant P4H was expressed in E. coli .", "Briefly, DNA encoding the signal sequence of P4H was cloned into pET28_N-His_TEV, the resulting plasmid pET28_N-His_TEV_P4HA1/PDI was transferred to E. coli Origami2(DE3) to co-expressed.", "The enzyme obtained was purified with MonoQ ion-exchange column, TEV digested and confirmed by MS, passed through Histrap HP column, finally purified with Hiload16/60 superdex 200 column.", "Example 3 Assays of the Enzymatic Activity of P4H and the Influence of the Compound of the Present Invention to the Enzymatic Activity [0158] The measurement of the enzymatic activity of purified P4H zymoprotein and the assay of the influence of the compound to the enzymatic activity were performed at the following coupling enzymatic reaction system: 100 mM Tris (pH7.0), 0.1 mM (NH 4 ) 2 Fe(SO 4 ) 2 , 0.1 mM ascorbic acid, 0.2 mM CoA, 0.2 mM ATP, 0.5 uM succinyl CoA synthase, 100 uM 2-oxoglutarate, 100 uM (Pro-Pro-Gly) 10 peptide, 50 nM P4H enzyme, 50 ul total.", "After 45 min reaction at 25° C., 10 ul MLG R1 was added and reacted for 10 min, 10 ul MLG R2 was added and reacted for 20 min.", "P4H catalyst 2-oxoglutaric acid and polypeptide with coenzyme and suitable enzyme reaction environment to give product succinic acid.", "The product succinic acid then produced succinyl CoA and phosphoric acid with the action of succinyl CoA synthase.", "The level of generated phosphoric acid could be measured by MLG, which reflects the level of P4H.", "The generated green product (MG+)(H 2 PMo 12 O 40 ) was measured at OD 630 nm.", "[0159] The evaluation of the inhibition of compound about P4H enzyme was performed in 96-well plates.", "Every concentration has two duplicate samples (n=2).", "Compound 9c was added to the enzymatic reaction system in following concentrations (in sequence and before the addition of P4H enzyme): 0.01, 0.03, 0.1, 0.3, 1, 3, 30, 100, 300 nM.", "Data analysis and statistics was performed by Prism.", "IC50 of compound 9c to enzyme is 8.1 μM ( FIG. 1 ).", "FIG. 1 indicates, the inhibition of compound 9c to the activity of human P4H enzyme is higher as the concentration of 9c is higher.", "Example 4 Studies of In-Vivo Pharmacokinetic [0160] Wistar rats (200±20 g) were divided into 2 groups, 6 each, half female and half male in each group, ate and drank freely.", "The first group was given compound 16c 3 mg·kg −1 caudal-intravenously.", "The second group was orally administered disodium salt of compound 27 (39 mg·kg −1 ).", "Blood (0.3 mL) was collected from retroorbital vein at time point 0 h, 0.08 h, 0.17 h, 0.33 h, 0.5 h, 0.75 h, 1 h, 1.5 h, 2 h, 3 h, 5 h, 7 h, placed into cold heparinized Eppendorf tubes.", "The samples were centrifuged at 4° C. (15000 rpm) for 5 min.", "Transfer 100 μL plasma sample to −80° C. freezer for test.", "[0161] Quantitative LC-MS/MS analysis methods of compound 9c and prodrug 16c in plasma were set up, using diazepam and mildronate as internal standard, respectively.", "(Prodrug 27 was not detected under experimental condition from plasma) the plasma sample was tested and analyzed.", "(result see in Table 1 and FIG. 2 ) [0000] TABLE 1 The concentration of compound 16c in plasma after compound 16c iv dosing and compound 27 PO dosing Route of Com- adminis- C max * t 1/2 ** AUC 0-t *** AUC 0-∞ **** pound tration (ng · mL −1 ) (h) (μg · h · L −1 ) (μg · h · L −1 ) 16c IV 1617.80 1.50 2064.58 2136.40 27 PO 1440 2.79 5235.70 6805.74 *C max refers to peak concentration in plasma **t 1/2 refers to half life of drug in plasma ***AUC 0-t refers to area under concentration-time curve until final test time ****AUC 0-∞ refers to area under concentration-time curve until total clearance of drug Oral Bioavailability: [0162] Oral Bioavailability was calculated according to compound 16c in plasma.", "Area under concentration-time curve (AUC) of PO dosing was divided by AUC of iv dosing of same amount of drugs, expressed as absorption percentage: Bioavailability (F)=AUCpo·Miv/AUCiv·Mpo×100%.", "Wherein, Miv means the molar concentration of drugs by iv dosing, and Mpo means the molar concentration of drugs by PO dosing.", "The AUC 0-t of compound 16c in plasma [0163] After compound 16c (3 mg·kg −1 ) was intravenously administered and compound 27 (39 mg·kg −1 ) was orally administered, the AUC 0-t of compound 16c in plasma is 2064.58 g·h/mL and 5235.70 g·h/mL, respectively.", "Based on the concentration of compound 16c in plasma, the bioavailability (F) of compound 27 is 25.4% (i.", "e 5235.70/(2064.58×10)×100%).", "Concentration of Compound 16c and 9c in Liver: [0164] 16 Wistar rats (200±20 g) were divided into 4 groups randomly, female and male each half in each group, ate and drank freely before the experiment.", "After PO dosing of compound 27 (39 mg·kg −1 ), rats were sacrificed at each time point 15 min, 45 min, 8 h, 24 h. Liver samples were collected, washed off blood and contents with saline, cut into small pieces, and stirred evenly.", "1 g was weighed.", "1 mL Methanol/water was added.", "After homogenated, additional 1 mL methanol/water was added.", "The mixture was sonicated for 15 seconds, centrifuged (4500 rpm) for 10 minutes.", "The upper clear solution was tested using LC-MS/MS method to give the concentration of compound 16c and 9c in liver at different time points after administration (table 2).", "The results indicate that prodrug 27 converted to compound 16c in rat after PO dosing, and compound 16c converted to compound 9c in liver.", "[0000] TABLE 2 concentration of compound 16c and 9c (ng · g −1 )in liver at different time points after oral administration of compound 27 0.25 h 0.75 h 8 h 24 h 16c 521.50 662.5 584.50 50.88 9c 16.13 64.25 44.68 3.55 Example 5 Study of In-Vivo Pharmaceutical Efficacy [0165] This experiment used Bile Duct Ligation to induce liver fibrosis model in rats.", "Treatment of BDL rats with PO dosing prodrug 27 was studied.", "[0166] Briefly, Wistar rats (200±20 g) were divided into 3 groups, half female and half male in each group: [0167] SHAM group: 6 rats were anaesthetized, the abdominal skin was shaved and sterilized regularly, the common bile duct was exposed by an upper abdominal midline incision with sterile operation.", "Muscle and skins were sutured separately.", "[0168] liver fibrosis MODEL group: 12 rats were anaesthetized, the abdominal skin was shaved and sterilized regularly, the common bile duct was exposed and ligated by an upper abdominal midline incision with sterile operation.", "Muscle and skins were sutured separately.", "[0169] Dosing group: 12 rats were anaesthetized, the abdominal skin was shaved and sterilized regularly, the common bile duct was exposed and ligated by an upper abdominal midline incision with sterile operation.", "Muscle and skins were sutured separately.", "After operation, disodium salt of compound 27 (30 mg/kg) was dissolved in water and dosed orally to the rats once per day test indexes: [0170] After 2 weeks, measure the ALT and AST of serium and liver homogenate [0171] After 2 weeks, rats were sacrificed, and liver performed HE staining and Masson staining.", "The Influence of Compound 27 Orally Administrated on the ALT and AST of the Serium and Liver Homogenate of BDL Rats Having Liver Fibrosis [0172] ALT and AST were liver function index in common clinical use now.", "ALT mainly exists in the cytosol of hepatocyte, AST mainly exists in the mitochondria of hepatocyte.", "When hepatocyte is damaged, the level of ALT and AST in serium rise, which could reflect the level of the damage of hepatocyte.", "The ALT and AST of the serium and liver homogenate of rats in model group with BDL rised significantly.", "After compound 27 was administrated for 14 days, animals were sacrificed.", "The ALT and AST of the serium and liver homogenate of those animal decreased significantly, which have significant difference comparing with model group (**P<0.01, see on Table 3 and Table 4).", "It's indicated that compound 27 alleviated the level of the damage of liver function with BDL, and have protection effect to liver damage resulted from bile regurgitation.", "[0000] TABLE 3 The influence of compound 27 on the ALT (IU/L) of the serium of BDL rats having liver fibrosis groups ALT in serum ALT in liver SHAM 67.1 ± 5.45 68.2 ± 8.33 MODEL 144.4 ± 15.94 136.8 ± 16.48 Compound 27 74.4 ± 17.82** 76.4 ± 11.35** (30 mg/kg) **P <", "0.01, compared to MODEL group [0000] TABLE 4 The influence of compound 27 on the AST (IU/L) of the serium of BDL rats having liver fibrosis groups AST in serum AST in liver SHAM 67.7 ± 4.67 67.40 ± 5.28 MODEL 207.2 ± 30.96 198.75 ± 27.70 Compound 27 87.2 ± 12.51** 91.42 ± 8.79** (30 mg/kg) **P <", "0.01, compared to MODEL group The Influence of Compound 27 Orally Administrated on the HE Staining of BDL Rats Having Liver Fibrosis [0173] H&E staining results as follow: [0174] Sham group: depicted in FIG. 3 , the structure of hepatic lobule is normal, hepatocytes centre on central veins and radiate out in all directions.", "The hepatocytes in hepatic lobule range in order.", "The size of hepatocytes is even.", "There is no the degeneration and necrosis of hepatocytes.", "[0175] Model group: depicted in FIG. 4 , the structure of hepatic lobule is inordinate.", "[0176] Hepatocytes swelling.", "The cytoplasm of hepatocytes is loose.", "The connective tissue of fibrosis proliferate.", "[0177] Dosing group: depicted in FIG. 5 , the treating group varies the pathological changes of hepatic tissue." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] Not Applicable. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH [0002] Not Applicable. BACKGROUND OF THE INVENTION [0003] 1. Field of the Invention [0004] The disclosed invention relates generally to conducting auctions, and in particular to restricting access to market information in online electronic auctions. [0005] 2. Description of the Background [0006] Procurement and selling of supplies has traditionally involved high transaction costs. Particularly, the cost of information searching regarding suppliers and sellers and their goods and services has often been prohibitively high. The introduction of electronic commerce has introduced new methods of procurement and selling that lower some of the transaction costs associated with procurement. Online procurement, or business-to-business electronic commerce, matches purchasers and suppliers so that transactions can take place electronically. The terms “purchaser” and “buyer” are used interchangeably herein to describe the party that desires to purchase goods or services in an auction. The terms “supplier” and “bidder” are used interchangeably herein to describe the party that desires to sell goods or services in the auction. Three models for online procurement are catalog, buyer-bidding auction, and supplier-bidding auction. [0007] The “catalog” model of online procurement allows customers to obtain information regarding products and services from a single supplier, i.e., single-source catalogs. Early electronic catalogs were developed by individual suppliers to help customers obtain information about products provided by the developing supplier and order those products electronically. Customers, however, were often not satisfied with such single-source catalogs but rather preferred to compare a number of competing products to facilitate a comparison of features and pricing. Thus, certain suppliers began to include competitors' products on their systems. By offering competing products in one catalog, those suppliers created “electronic markets.” [0008] The electronic markets created by suppliers, however, could be biased toward the supplier offering the electronic market. Thus, unbiased electronic markets that promote competition were developed to further lower purchase prices. [0009] For standard products and services, third party market makers compiled databases of related products and services from various suppliers to provide a single market from which similar products and services may be compared and through which those goods and services may be purchased. Purchasers may, thus, access the database of such a third party market, view information and pricing information related to each desired product or service, and order the desired products and services in a single visit to the third party database. [0010] When many purchasers compete for the right to buy from one supplier, a buyer-bidding auction model is created. In a certain buyer-bidding auction, potential purchasers compete for a product or service by submitting one or more bids to a website operated by the buyer-bidding auction coordinator. After the bids have been received, the supplier may choose to accept the highest bid, thereby binding the high bidder to a contract for the sale of the product or service. [0011] The catalog and buyer-bidding auction types of electronic markets, however, do not work well in some situations. For example, if the required product is custom made for the purchaser, it is difficult for suppliers to publish a set price in advance for a catalog market. Likewise, it is difficult for purchasers to specify all of the details of the product they want to purchase in a buyer-bidding auction. [0012] Traditionally, when a company required a custom industrial product, procurement was made by a purchaser for the company who searched for potential suppliers and acquired custom price quotes from those suppliers for the needed custom product. The search process tended to be slow because suppliers had to be sought out and then negotiations had to take place. The search process also tended to be somewhat random because it often relied heavily on personal relationships between purchasers and suppliers. There were also significant costs associated with locating vendors, comparing products, negotiating, and paperwork preparation in a purchase decision. The cost of switching suppliers may also be prohibitive because of the cost of searching for other qualified suppliers. Thus, purchasers disadvantageously received price quotes from existing suppliers that were not the lowest price that could have been obtained by a more thorough supplier search. New suppliers were also placed at a disadvantage due to the difficulty and cost of marketing to purchasers who have existing suppliers. [0013] As an alternative, purchasers may use on-line auctions having prequalified bidders to save money. The assignee of the present application developed a system, wherein suppliers downwardly bid against one another to achieve the lowest market price in a supplier-bidding, auction. [0014] In a supplier-bidding auction, bid prices typically start high and move downward in a reverse-auction format as suppliers interact to establish a low price at the close of the auction. The auction marketplace is typically one-sided, i.e., one purchaser and many potential suppliers. Either goods or services may be purchased in an auction, and the goods may be of any type including, for example, office products, finished products, other products, parts, components, or materials. “Components” typically are fabricated tangible pieces or parts that are assembled into durable products. Example components include gears, bearings, appliance shelves, and door handles. “Materials” are often raw materials that may be purchased in bulk and that are further transformed into product. Example materials include corn syrup and sheet steel. [0015] Furthermore, industrial purchasers often desire to purchase more than one component at a time. They may purchase whole families of similar components or groups of components that are related to one another by, for example, the final product into which they are incorporated. As an example, a purchaser might purchase a given plastic knob in two different colors, or might purchase a nameplate in four different languages. Those parts may be so similar that it is only practical to purchase the parts from the same supplier because, for example, all of the knobs can be made using the same mold. Those items are therefore grouped into a single lot. Suppliers in industrial auctions may, therefore, be required to provide unit price quotes for all line items in a lot. [0016] The process for a supplier-bidding auction is described below with reference to FIGS. 1 and 2. FIG. 1 illustrates the functional elements and entities in a supplier-bidding auction 56 , while FIG. 2 is a diagram that identifies the tasks performed by each of the involved entities. [0017] The supplier-bidding auction model typically requires that the bidding product or service be defined by the purchaser 10 . An auction coordinator 20 may work with the purchaser 10 to prepare for and conduct an auction 56 and to define potential new supply relationships resulting from the auction 56 . [0018] In the example illustrated in FIG. 2, the purchaser 10 provides data to the coordinator 20 in the Initial Contact phase 102 of the auction 56 . The coordinator 20 then prepares a specification 50 for each desired product 52 . Once the product 52 is defined, potential suppliers 30 for the product 52 are identified. The coordinator 20 and purchaser 10 work together to compile a list of potential suppliers from suppliers already known to the purchaser 10 as well as suppliers recommended by the coordinator 20 . [0019] The purchaser 10 makes a decision regarding which potential suppliers 30 will receive invitations to the upcoming auction 56 . Suppliers 30 that accept auction invitations are then sent notices regarding the upcoming auction 56 . In certain situations, suppliers 30 may also receive software to install in preparation of participating in the auction 56 . [0020] In the RFQ phase 104 illustrated in FIG. 2, the coordinator 20 works with the purchaser 10 to prepare a Request for Quotation (“RFQ”) 54 . The coordinator 20 collects and maintains the RFQ data provided by purchaser 10 , and then publishes the RFQ 54 , and manages the published RFQ 54 . The RFQ 54 includes specifications 50 for all of the products 52 covered by the RFQ 54 . In the RFQ 54 , the purchaser 10 may aggregate products into job “lots.” The purchaser 10 may also separate unlike products into separate lots to best fit the needs of the purchaser 10 and the capabilities of suppliers 30 . Lots, therefore, may include such things as aggregations of similar parts or products that are desired to be purchased together. That type of aggregation allows suppliers 30 to bid on that portion of the business for which they are best suited. [0021] During the auction 56 , bids 58 may be placed on individual lots (and their constituent parts 52 ) within the RFQ 54 . While suppliers 30 may be required to submit actual unit prices for all line items, the competition in an auction 56 is generally based on the aggregate value bid for lots. The aggregate value bid for a lot depends upon the level and nix of line item bids and the quantity for each line item. Therefore, suppliers 30 may submit bids at the line item level, but compete on the lot level. [0022] In the Auction Administration phase 106 , the coordinator 20 coordinates the auction 56 and administers the auction setup and preparation. The coordinator 20 sends an RFQ 54 to each participating supplier 30 , and assists participating suppliers 30 to prepare for the auction 56 . [0023] In the Conduct Auction phase 108 , suppliers 30 submit bids 58 on the lots and monitor the progress of the bidding by the participating suppliers 30 . The coordinator 20 assists, observes, and administers the auction 56 . [0024] When the bidding period is over, the auction 56 enters the Administration of Auction Results phase 110 . In that phase, the coordinator 20 analyzes and administers the auction results, which are viewed by the purchaser 10 . The purchaser 10 begins to qualify the low bidding supplier 30 or suppliers 30 . The purchaser 10 generally retains the right not to award business to a low bidding supplier 30 based on final qualification results or other business concerns. [0025] In the ensuing Contract Administration phase 112 , the coordinator 20 facilitates settlements 60 awarded by the purchaser 10 to suppliers 30 . Contracts 62 are then drawn up between the purchaser 10 and suppliers 30 . [0026] The auction 56 is conducted electronically between potential suppliers 30 at their respective remote sites and the coordinator 20 at its site. As shown in FIG. 3, information is conveyed between the coordinator 20 and the suppliers 30 via a communications medium such as a network service provider 40 accessed by the participants through, for example, dial-up telephone connections using modems, or direct network connections. A computer system may be used to manage the auction 56 . The computer system may have two components: a client component and a server component. The client component may operate on a computer at the site of each potential supplier 30 or may be accessed via a supplier computer. The client component is used by suppliers 30 to make bids during the auction 56 . The bids are sent via the network service provider 40 to the site of the coordinator 20 , where they are received by the server component of the software application. [0027] The purchaser 10 may access the auction 56 through the auction coordinator 20 as illustrated in FIG. 3, or may alternately access the auction 56 through a network service provider 40 . [0028] In auctions 56 , and in particular reverse auctions, it is desirable that bidder/suppliers 30 actively participate in the auction 56 by submitting lower bids on a regular basis throughout the duration of the auction 56 . It is expected that each bidder 30 will consider factors including bids of the other bidders 30 , their own costs, and potential efficiencies that may be had that will reduce the cost to the bidder 30 such that the bidder 30 may submit a reduced bid to the purchaser 10 . In certain auctions 56 , however, it has been discovered that certain bidders 30 hold back their bids until late in the time allotted for the auction 56 . Other bidders 30 choose not to bid at all during the auction 56 . A decision not to bid during an auction 56 may be made for many reasons. One reason for not bidding occurs when the bidder 30 is not desirous of being awarded a contract in the auction 56 , but rather is gathering information, such as, for example, the price at which suppliers 30 are willing to provide goods and services. When bidders 30 hold their bids until late in the auction 56 or do not bid at all, the benefit of competitive bidding to the purchaser 10 is lost or reduced. Furthermore, purchasers 10 and bidders 30 alike may prefer to avoid providing such information to non-participants to protect the confidentiality of the auction 56 . [0029] Thus, there is a need for a system and process whereby bidders 30 are encouraged to place a bid 58 . There is a further need for a system and process whereby bidders 30 are provided with an incentive to actively participate in an auction 56 by submitting additional, progressively lower bids 58 throughout the auction 56 . There is also a need for a system and method of bidding that protects bidding confidentiality. SUMMARY OF THE INVENTION [0030] In accordance with a particularly preferred form of the present invention, there is provided a method and system for conducting an auction having at least two competing bidders is disclosed. The method includes receiving bid data from at least one bidder and providing the bid data to each bidder that meets a condition for receiving the bid data. [0031] An apparatus for determining a suggested bid value that surpasses a selected bid is also disclosed. The apparatus includes a computer readable medium having stored thereon instructions which, when executed by a processor, cause the processor to provide a user selectable facility which, when selected establishes the value of the selected bid, calculates the suggested bid value by subtracting a predetermined minimum differential value from the selected bid value, and conveys the suggested bid value to the user. [0032] Thus, the present invention provides a method, apparatus and system that beneficially encourages bidders to place a bid. [0033] The present invention also provides a method, apparatus and system that beneficially provides bidders with an incentive to actively participate in an auction by submitting additional, progressively lower bids throughout the auction. [0034] In addition, the present invention also provides a method, apparatus and system that beneficially protects bidding confidentiality. [0035] Accordingly, the present invention provides solutions to the shortcomings of prior online auctions. Those of ordinary skill in the art will readily appreciate, therefore, that those and other details, features, and advantages will become further apparent in the following detailed description of the preferred embodiments. BRIEF DESCRIPTION OF THE DRAWINGS [0036] The accompanying drawings, wherein like reference numerals are employed to designate like parts or steps, are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, and illustrate embodiments of the invention that together with the description serve to explain the principles of the invention. [0037] In the drawings: [0038] [0038]FIG. 1 is a schematic illustration of the elements and entities involved in an embodiment of an auction; [0039] [0039]FIG. 2 is a tabular illustration of the tasks performed by the entities involved in the auction of FIG. 1; [0040] [0040]FIG. 3 is a schematic illustration of the communications links between the coordinator, the buyer, and the suppliers in the auction of FIG. 1; [0041] [0041]FIG. 4 is a schematic diagram of an auction network; [0042] [0042]FIG. 5 is a flow diagram illustrating an information flow of the present invention; [0043] [0043]FIG. 6 is a sample purchaser screen display that may be used to practice an embodiment of the invention; [0044] [0044]FIG. 7 is a sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 6; [0045] [0045]FIG. 8 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 6; [0046] [0046]FIG. 9 is a flow diagram illustrating another information flow of the present invention; [0047] [0047]FIG. 10 is a flow diagram illustrating yet another information flow of the present invention; [0048] [0048]FIG. 11 is a sample purchaser screen display that may be used to practice an embodiment of the invention; [0049] [0049]FIG. 12 is a sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11; [0050] [0050]FIG. 13 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11; [0051] [0051]FIG. 14 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11; [0052] [0052]FIG. 15 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11; and [0053] [0053]FIG. 16 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11. DETAILED DESCRIPTION [0054] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. It is to be understood that the Figures and descriptions of the present invention included herein illustrate and describe elements that are of particular relevance to the present invention, while eliminating, for purposes of clarity, other elements found in typical auction systems and computer networks. The present invention described below extends the operation of the inventive auction systems and methods described in greater detail in co-pending application Ser. No. 09/252,790, entitled “Method and System for Controlling Closing Times of Electronic Auctions Involving Multiple Lots” filed Feb. 19, 1999, and co-pending Application Ser. No. 09/282,157, entitled “Method and System for Conducting Electronic Auctions with Transformation Bidding” filed Mar. 31, 1999, the disclosures of which are hereby expressly incorporated in the present application. [0055] The preferred embodiments described herein utilize an online reverse auction, wherein the present invention is performed by a computer processor, as an example. In those examples, suppliers 30 bid to supply goods or services to a purchaser 10 and the purchaser 10 typically purchases the goods or services from the lowest priced qualified bidder 30 . It is to be understood, however, that the present invention may be used in other applications. The auction 56 would not necessarily have to occur online and the present invention may be performed by other than a computer processor. The present invention may also be utilized in connection with auctions other than reverse auctions. For example, the present invention may be advantageously utilized with forward auctions, wherein the party offering the highest priced qualified bid, rather than the lowest priced qualified bid, is awarded the goods or services being sold. In the case of a forward auction, the leading bid is the highest amount offered and the leading bidder 30 is the purchaser party 10 making that highest offer, while in a reverse auction, the leading bid is the lowest amount offered and the leading bidder 30 is the supplier party 30 making that lowest bid. Similarly, placing a “better bid” in a reverse auction indicates placing a lower bid, while placing a “better bid” in a forward auction indicates placing a higher bid. [0056] [0056]FIG. 4 is a diagram illustrating an auction network 70 of the present invention for operating an auction. The auction network 70 may be divided into three functional sections; a client access network 71 , a communications network 73 , and a data processing network 76 . The client access network 71 may, for example, include one or more client machines 72 for accessing and communicating with the communications network 73 . The communications network 73 may include one or more primary communications servers 74 , secondary communications servers 75 , and directory, login and reporting servers 90 . The data processing network 76 may include production servers 77 , training and reporting servers 80 , reporting and training databases 86 , and production databases 84 . The production servers 77 and training and reporting servers 80 are referred to collectively herein as bid servers 77 and 80 . [0057] The client machines 72 may be, for example, personal computers located at each bidder 30 and purchaser site 10 for accessing the auction 56 . The client machines 72 may access the auction 56 by, for example, connecting to a web site operated by the party hosting the auction 56 . The client machines 72 may also receive software from the communications network 73 that facilitates communications with the communications network 73 . [0058] The primary communications servers 74 are utilized to provide information to bids 58 received from the client machines 72 to the bid servers 77 and 80 , and to provide that bid information from the bid servers 77 and 80 to the client machines 72 . The primary communications servers 74 may furthermore act as a firewall to prevent direct access to the bid servers 77 and 80 by the client machines. The secondary communications servers 75 act as backups to the primary communications servers 74 . The secondary communications servers 75 will perform the communication functions normally performed by the primary communications servers 74 if a failure occurs in the primary communications servers 74 , thereby providing redundancy to the auction network 70 . [0059] The directory, login, and reporting servers 90 may perform a variety of functions that may be performed by a single server or include separate servers for the various functions. The directory, login, and reporting servers 90 may include a web server that acts as a portal for access to the auction network 70 . As such, the directory, login, and reporting servers 90 will receive login requests for access to the auction network 70 via, for example, the Internet. The directory, login, and reporting servers 90 may make access decisions as to whether a client machine 72 is permitted to access the communications network 73 . If access is permitted, the directory, login, and reporting servers 90 will direct the client machine 72 to the appropriate portion of the auction network 70 . The directory, login, and reporting servers 90 , may provide reports to client machines 72 . For example, information from prior auctions 56 which may be utilized by purchasers 10 to make a decision as to which bidder 30 will be awarded the sale and to permit the purchaser 10 to consider the way in which the auction 56 proceeded so that future auctions 56 may be refined. [0060] The production servers 77 run the bidding software that facilitates auctions 56 as they occur. The production servers 77 may communicate with client machines 72 through primary and secondary communications servers 74 and 75 . The production servers 77 may also be redundant so that if a failure occurs in the production server 77 that is being utilized in an auction event 56 , the redundant backup production server 77 may perform the functions of the failed production server 77 and, thus, prevent failure of the auction 56 . [0061] The training and reporting servers 80 operate in a manner similar to the production servers 77 and provide reports for auctions 56 . It is useful to operate test auctions 56 to test the operating systems and to train personnel and clients. Such testing may be performed on the production servers 77 or, to prevent any degradation of system operation in actual auctions 56 , one or more separate training servers may be utilized for testing and training. Reporting may also be accomplished on the production servers 77 or the report creation functions may be offloaded to one or more reporting servers 80 . The reporting servers 80 may furthermore be combined with the training servers 80 . [0062] Data related to auctions 56 may be held in one or more storage devices. The data storage devices may, for example, be a magnetic storage device, a random access memory device (RAM), or a read only memory device (ROM). The data may include pre-auction data, post auction data, and data that is related to active auctions 56 . Pre-auction data may include, for example, suppliers 30 that are permitted to bid on a particular auction 56 and the scheduled auction starting and ending times. Post auction data may include the bids and bid times received in a particular auction 56 and reports displaying that data in user friendly formats. Active auction data may include data received from the bidders 30 as the auction 56 is taking place and related data such as the rank of each bidder 30 . [0063] The “rank” of the bidders 30 is determined by comparing the lowest amount bid by each bidder 30 and ordering the bidders 30 according to those lowest bids. The bidder ranked first is the bidder 30 that has bid an amount lower than any other bidder 30 in a reverse auction. The last rank may be a rank equal to the number of bidders 30 who have submitted bids in the auction 56 , and the bidder 30 having that last rank is the bidder 30 that has submitted the highest amount in a reverse auction that is based on price only. Of course, there are many known ways to calculate rank, and any of those may be used in connection with the subject invention. The other bidders 30 are ranked between first and last according to the amounts of their lowest submitted bids. Thus, a higher, or better ranked bidder 30 in a reverse auction is a bidder 30 who has placed a comparatively lower bid, while a higher, or better ranked bidder 30 in a forward auction is a bidder 30 who has placed a comparatively higher bid. An auction 56 may alternately be based on one or more factors other than price, such as quality, delivery factors, and/or other factors that are referred to herein collectively as “total value.” Thus, rank may also be based on factors other than price, including total value and any other factor that is useful in an auction 56 setting. A bid or bid amount is a value that is submitted by each participating bidder 30 for comparison to the bids of other bidders 30 , and may likewise be based on a variety of bid factors that are considered important to the bid participants. Those factors may include, for example, price, quality, other costs such as delivery costs, or a total value. Bids may also be placed in a number of ways including, for example, absolute total value, or comparative value such as bidding in relation to an index price. [0064] Three databases, or groupings of databases, are incorporated into the auction network illustrated in FIG. 4. The production databases 84 hold data that will be used by or is received from the production servers 77 , while the reporting and training databases 86 hold data that will be used by or is received from the training and reporting servers 80 . [0065] The directory, login, and reporting servers 90 illustrated provide a web portal for the client machines 72 . The directory, login, and reporting servers 90 provide an initial contact point for the client machines 72 , access to auctions 56 in which the client machine 72 is permitted to participate, and reports relating to active and closed auctions 56 . [0066] One skilled in the art will recognize that certain components of the network described herein, while beneficial to an auction network, are not necessary components in an operational auction network. For example, the secondary communications servers 75 could be removed where the benefit of redundancy is not desired, and the primary communications servers 74 could be removed and the client machines 72 could communicate directly with the bid servers 77 and 80 . [0067] In a business-to-business online auction 56 , bidders 30 may compete openly using their identities, or anonymously wherein bidders 30 view bids 58 placed by other bidders 30 but do not know the identity of those other bidders 30 . Feedback about bidding activity is referred to as “market feedback” and includes any information or data related to the bidders 30 or their bids or interrelationships between those bids, and any other bid related information or data such as, for example, the quality of goods being sold, that is received before or during the auction 56 . Market feedback may include, for example, bids that have been placed by other bidders 30 , the rank of a participants bid in relation to the other bidders 30 , the identity of bidders 30 in relation to their bids or rank, or any subset of that information. Market feedback may also include non-pricing information such as, for example, the quality of the goods to be provided by bidders 30 and shipping costs associated with one or more bidders 30 . Providing such market feedback to bidders 30 in an auction 56 helps create real-time competitive interaction among participants in the auction 56 because, without feedback, bidders 30 would have less incentive to revise their price quotes and place additional bids to remain competitive. [0068] In a certain type of online auction 56 , which may be referred to as “full market feedback format,” all bids 58 are visible to every bidder 30 . Bids 58 are sorted from highest to lowest. Thus, each bidder 30 can assess its rank and competitive position if bidders 30 are individually identified, by comparing its current best bid 58 with other bids 58 placed in the online auction 56 . [0069] In a second type of online auction 56 , bidders 30 are provided with only their own current best bid 58 and the current market-leading bid. Bidders 30 are not aware of every bid 58 placed by other participants, but they can assess their competitive position against the current market-leading bid. In one variation of that second type of online auction 56 . bidders 30 also receive feedback about their current rank. [0070] Table 1 illustrates an example of a series of bids 58 placed by different bidders 30 participating in an online reverse auction 56 . Each row includes information related to a single bid 58 and the rows are ordered from highest bid to lowest bid. In the example illustrated in Table 1, each bidder 30 is identified anonymously. The first column lists a bidder identifier that is used in connection with all bids submitted by a particular bidder 30 . The second column lists the time the associated bid 58 was received and the third column lists the amount of bid 58 . The fourth column indicates the dollar value difference between the bid 58 and the lowest current bid 58 (“market-leading bid”) and the fifth column lists the percentage difference between the bid and the lowest current bid 58 . The sixth column indicates the current rank of each bidder 30 next to the best bid 58 submitted by each bidder 30 . Table 1 illustrates all of the bids 58 placed by every bidder 30 . TABLE 1 A. All bids Bids vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $128,000 23.62%  Bidder B 1:01:23 PM $664,000 $122,000 22.51%  Bidder C 1:01:28 PM $560,000  $18,000 3.32% Bidder B 1:03:10 PM $559,000  $17,000 3.14% Bidder D 1:02:50 PM $558,500  $16,500 3.04% 7 Bidder A 1:03:38 PM $558,300  $16,300 3.01% 6 Bidder E 1:05:12 PM $557,700  $15,700 2.90% 5 Bidder F 1:05:43 PM $557,500  $15,500 2.86% Bidder C 1:06:49 PM $552,000  $10,000 1.85% Bidder G 1:06:55 PM $549,000  $7,000 1.29% Bidder C 1:07:22 PM $546,800  $4,800 0.89% Bidder F 1:07:49 PM $546,400  $4,400 0.81% 4 Bidder C 1:08:02 PM $546,250  $4,250 0.78% 3 Bidder B 1:08:17 PM $545,000  $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000     $0 0.00% 1 [0071] Applying the full market feedback format to the example illustrated in Table 1, each bidder 30 sees all of the information contained in Table 1 and is thus able to determine its rank and the difference between its best bid and the market-leading bid. For example, at 1:08:44 PM Bidder B can see that it is in second place, $3,000 above the market-leading bid placed by Bidder, G. Bidder F can see that it is in fourth place, $4,400 above the market-leading bid placed by Bidder G, $1,400 above Bidder B in second place, and $150 above Bidder C in third place. [0072] Each bidder 30 also receives market feedback regarding all bids 58 placed up to that time throughout the auction 56 if the full market feedback format is utilized. Thus, at 1:04:00 PM, the market-leading bid 58 is held by Bidder A, who placed a bid of $558,300 at 1:03:38 PM. That bid, and all other bids placed prior to that time are visible to all bidders, including Bidder E, who at that point in the auction 56 has not placed a bid 58 . By viewing the current market activity, Bidder E is able to formulate an appropriate first bid and submit a new market-leading, bid of $557,500 at 1:05:12 PM. [0073] The full market feedback format is particularly effective for many industrial commodities and supply markets but may be utilized in any type auction 56 . However, in certain auctions 56 , particularly those conducted in industrial and business-to-business settings, that form of market feedback generates sub-optimal results or unwanted side-effects that damage the integrity of the process. For example, in certain auctions 56 , the sponsor, which in the case of a reverse auction is typically the purchaser 10 , may not want pricing information to be disclosed to a large number of parties to minimize the likelihood that the pricing information will be released to the public. A sponsor may also wish to conceal the number of bidders that are available or participating in the auction 56 . In other auctions 56 , disingenuous participants will watch the auction 56 without bidding. Qualified bidders 30 that claim to be interested in bidding may view the entire auction 56 without ever submitting a bid. Such participants learn market pricing, information, and auction results that may have value for general business purposes beyond the scope of the particular supply opportunity up for bid. For many business-to-business auctions 56 , this is not a serious issue. For example, where the format of the auction 56 is such that bids are for aggregate “lots” of business consisting of many line items with individual unit prices, bidders 30 may compete at the lot level so that they see only aggregate or lot-level bids placed by other bidders 30 rather than the cost of each separate item being purchased. That severely limits the value of the pricing information certain bidders 30 are able to gather from watching the auction 56 because there is no way to deduce unit prices for separate items with any real accuracy. In certain other auctions 56 , the items for bid are custom-engineered components or inputs specific to a particular purchaser 10 such that the pricing information is not readily transferable or useful in other business contexts. [0074] For some auctions 56 , however, especially where the bidding format reveals unit pricing or the product is, for example, a commodity or standard item purchased by multiple purchasers 10 , allowing visibility to market pricing is a more sensitive issue for the genuine participants. In those cases, genuine bidders 30 may be discouraged from submitting the lowest price quotes they are prepared to offer due to fear that disingenuous competitors may be viewing the auction 56 and may use information learned from the auction 56 against the genuine bidders 30 in the marketplace beyond the particular supply opportunity up for bid. In extreme cases, that fear may be sufficient to discourage certain bidders 30 from participating in the auction 56 . For example, when a bidder 30 determines that the potential loss of the supply opportunity provided by the auction 56 is less damaging than the risk of damage that could occur to the entire base of business of the supplier 30 from revealing pricing information, the bidder 30 may opt not to participate in an auction 56 or not to price as aggressively in an auction 56 as the bidder 30 might otherwise. To guarantee full and aggressive participation, it is beneficial to assure bidders 30 that no bidders 30 are watching the auction 56 without actively participating themselves. [0075] In certain other auctions 56 , genuine participants may exploit market pricing learned from the auction 56 . There are circumstances where the supply industry dynamic is such that, even when all bidders 30 intend to participate, some bidders 30 will fail to participate, or will offer less aggressive quotes than they otherwise would, for fear that they will reveal critical pricing information that will “leak” into the marketplace and damage their businesses. For example, a losing bidder 30 may learn the identity of the successful bidder 30 in a particular auction 56 through industry gossip. In a subsequent competitive selling situation that losing bidder 30 may inform another purchaser 10 of the pricing that the successful bidder 30 quoted in the previous auction 56 . Thus, the winning bidder 30 is placed in an awkward position with subsequent purchasers 10 who may suspect that the successful bidder 30 had been supplying them with goods at a price higher than the bidder 30 was prepared to offer other customers. That situation may occur, for example, where (i) the bid format is structured to permit visibility to easily comparable pricing information (e.g., unit pricing); (ii) the commodity is a standard material purchased by multiple purchasers 10 (e.g., an industry standard grade of a particular chemical, such as 99% USP Food Grade Glycerin); and (iii) the industry structure is a consolidated “tight-knit” community where bidders 30 may learn the identity of the successful bidders 30 through market intelligence subsequent to the auction 56 . [0076] Another market feedback problem occurs in cases where bidders 30 , such as preferred suppliers 30 or “incumbent suppliers” (i.e., bidders 30 that are current or past suppliers 30 to the purchaser 10 ) bid significantly behind the market leading bid. In an auction 56 for an industrial component or input, for example, purchasers 10 may reserve the right to award to a non-low-bidding supplier 30 . That allows purchasers 10 to consider non-price factors, such as relationship history, service considerations, and location, that are material to establishing a supply contract with a particular bidder 30 . While the lowest bidder 30 generally enjoys a favored position with respect to receiving the award, the purchaser 10 may be prepared to trade-off a higher price for other benefits. Similarly, preferred suppliers 30 may believe that they can offer significant non-price benefits beyond the specified requirements, and may choose to bid at a premium to the market-leading bid. While that may not be an illogical bidding strategy or undesirable market dynamic, in certain situations suppliers 30 may over-estimate the premium the purchaser 10 is willing to pay for perceived non-price benefits. That may lead preferred suppliers 30 to offer significantly less aggressive price quotes than they otherwise would if they realized how little value the purchaser 10 truly places on the non-price benefits. Thus, a preferred supplier 30 may not realize its tactical en-or until the purchaser 10 awards the business to a more competitive supplier 30 . At that point, the auction 56 has closed and it is too late for the preferred supplier 30 to revise its bid to a lower value. The preferred supplier 30 will have, therefore, lost an opportunity to make a sale, and the purchaser 10 will also have lost the potential to award the sale to the preferred supplier 30 at a price within the expectation of the purchaser 10 . [0077] Another problem related to bidding behind the market occurs where incumbent suppliers 30 exploit market feedback to avoid competition. That problem may arise when a purchaser 10 selects a pricing structure, for example a fixed price or a differential price, that a non-incumbent supplier 30 must match or beat to be selected over an incumbent supplier 30 . In such a case, for example, an incumbent supplier 30 could know that the purchaser 10 favors the incumbent supplier 30 even at a price premium to the market. Because the purchaser 10 may pass over low bidders 30 , incumbent suppliers 30 can take advantage of their incumbent status. To ameliorate that disadvantage for new suppliers 30 , it is common to communicate a “reserve price” to all bidders 30 prior to the auction 56 . The reserve price represents the price at which the purchaser 10 will be willing to switch the business from the incumbent to a new source. Reserve price may be calculated in various ways including deducting the switching costs of the purchaser 10 from the “historic price” that the incumbent is currently charging the purchaser 10 . The use of such a reserve price affords new suppliers 30 an opportunity to offset the incumbent's advantage by ensuring that their bids are low enough for the purchaser 10 to recover any switching costs that Would otherwise prevent them from receiving the award. [0078] In certain embodiments, the reserve price may be permitted to fluctuate when an incumbent bids an amount lower than the historic price. In such a situation, when an incumbent lowers its bid to less than the historic price, then the effective price required for a purchaser 10 to switch to a new supplier 30 will be lower than a reserve price that was a fixed amount below the historic price. Since an incumbent may calculate the differential between reserve and historic prices when the reserve price fluctuates, and can view the low bid, the incumbent can exploit its position by bidding behind the market by an amount slightly less than the differential between the historic and reserve prices. While being a reasonable rationale for the incumbent, that situation does not allow the purchaser 10 to maximize the competitive dynamic between incumbent and potential new suppliers 30 . In addition, new suppliers 30 often perceive this situation to be unfair because they are unable to identify an incumbent when bidding is anonymous. [0079] It may thus be beneficial to reward more aggressive bidders 30 with more information about bidding activity in certain circumstances (i.e., the closer a bidder's 30 current bid is to the market-leading bid, the more information about other bids placed in the market is provided to that bidder 30 ). The present invention includes improved online auction technology that allows market feedback to be made visible to each bidder 30 according to that bidder's level 30 of participation and relative position in the market (“differential market feedback”). [0080] “Differential market feedback technology” includes a variety of feedback mechanisms that may be used to differentiate bidders 30 while “differential market feedback rules” are used to define when a bidder 30 can view market feedback and may use differential market feedback technology in that determination. An example of differential market feedback technology as it is used to measure the market position of each bidder 30 relative to all other bidders 30 involves comparing the highest bid of each bidder 30 to the current market-leading bid. Examples of differential market feedback technology as it is used to measure market position relative to fixed reference points include ranking each bidder 30 , calculating the percentage differential between the bids of two or more bidders 30 , and calculating the absolute differential between the bids of two or more bidders 30 . Market position may also be determined relative to a fixed reference point by comparing each bid to a reserve price selected by the purchaser 10 or a historic price paid by the purchaser 10 in the past. [0081] Differential market feedback rules may include consideration of factors including level of market participation and market position. Market participation can be measured, for example, by whether the bidder 30 has submitted a bid at all, or by whether the bidder 30 has submitted a bid within a pre-determined time period between current time and the last time a bid was placed by that bidder 30 . Market position can be measured, for example, relative to other bids in the auction 56 or relative to a fixed reference point. Other known methods of measuring market participation and market position are known to those skilled in the art and are intended to be encompassed by the present invention. [0082] Differential market feedback rules may also take into consideration the relative positioning of bidders 30 as determined by the differential market feedback technology. Depending on the participation and position of a bidder 30 , the bidder 30 may, for example, be provided no feedback as to the market, the rank of the bidder 30 , information regarding only bids that are greater than (worse than) the lowest bid of that bidder 30 , information regarding the next lowest bid to the best bid placed by the bidder 30 , information regarding the market-leading bid, or information regarding all bids placed. [0083] By combining feedback rules and feedback types, an auction 56 may utilize a differential market feedback format uniquely suited to the requirements of each auction 56 , wherein the differential market feedback technology dynamically adjusts the feedback visible to each bidder 30 depending on their position in the auction 56 and other factors. [0084] [0084]FIG. 5 is a flow diagram 120 illustrating an embodiment of the present invention wherein access to market feedback is restricted to those bidders 30 who have submitted at least one valid bid. This example, and other examples provided herein, assume that a computer processor is executing a set of instructions that perform the steps, however, it will be recognized by one skilled in the art that the instructions may be carried out by any known method. At 122 of the embodiment illustrated in FIG. 5, the auction 56 is commenced by accepting bids from the bidders 30 . The auction 56 normally begins at a scheduled time that has been prearranged by the auction coordinator 20 , the purchaser 10 and the bidders 30 . At 124 a bid is received from any bidder 30 participating in the auction 56 . That bid, as well as any other bid discussed herein, may be a bid that is created by a bidder 30 and submitted to the data processing network 77 from the client machine 72 by way of the communication network 53 . At 126 the processor determines which bidders 30 have submitted at least one bid and, for example, sets a flag identifying those bidders 30 as “bid participants” [0085] At 128 through 144 , an example is provided of the bid participant segment of this embodiment, wherein market feedback is provided only to those bidders 30 who have placed at least one bid and are, thus, bid participants. In that example, “n” represents the number of bidders 30 that are permitted by the auction coordinator 20 to participate in the auction 56 . At 128 , the processor checks to see whether Bidder one is a bid participant. At 130 , market feedback is provided to Bidder one if Bidder one is a bid participant and at 132 , market feedback is withheld from Bidder one if Bidder one is not a bid participant. [0086] Similarly, at 134 , the processor checks to see whether Bidder two is a bid participant. At 136 , market feedback is provided to Bidder two if Bidder two is a bid participant and at 138 , market feedback is withheld from Bidder two if Bidder two is not a bid participant. The processor will continue by considering the bid participant status of each bidder 30 and provide market feedback to only those bidders 30 who are bid participants. At 140 , the processor checks to see whether the last bidder 30 (Bidder n) is a bid participant. At 142 , market feedback is provided to Bidder n if Bidder n is a bid participant and at 144 , market feedback is withheld from Bidder n if Bidder n is not a bid participant. [0087] After the bid participant segment has been completed, the processor will determine whether the auction closing time has arrived at 146 . If the auction closing time has not arrived, the processor will return to 124 to receive additional bids. Each time a new bid is received the processor will update the bid participant status of the bidders 30 and provide market feedback to all bid participants. If the auction closing time has arrived, the auction 56 will close and no additional bids will be accepted. [0088] Additional conditions may be placed on a bidder 30 prior to permitting the bidder 30 to access market feedback. As an example of one condition, any bidder 30 that places a noncompetitive bid, (i.e., a bid in excess of a predetermined amount in a reverse auction) is not permitted to view market feedback until that bidder 30 places a competitive bid. Such a competitive bid may include a bid that is less than a predetermined amount in a reverse auction and a bid that is greater than a predetermined amount in a forward auction. Alternately or in addition, a bidder 30 who is receiving market feedback may stop receiving market feedback if an extended period of time has elapsed since that bidder 30 placed its last bid, or if the bid is determined to be invalid. Another method of assuring that each bidder 30 places at least one competitive bid, is to require each bidder to submit and commit to such a competitive bid prior to commencement of the auction 56 . The auction 56 may then begin by having the auction coordinator 20 enter those bids into the auction network 70 . [0089] FIGS. 6 - 8 illustrate sample screens that may be displayed for various participants in a particular auction 56 utilizing the rule that access to market feedback is restricted to those bidders 30 who have submitted at least one bid. FIG. 6 illustrates a sample of a screen 150 that may be displayed to the purchaser 10 . A lot listing 152 includes statistics related to three lots of parts that are being auctioned. Lot three is highlighted in the lot listing 152 , indicating that lot three is active in the rest of the screen 150 . At 154 , statistics for all three lots are displayed and at 156 additional statistics for lot three are displayed. A bid history 158 , listing bids received for lot three, is also provided because lot three is the active lot. The lot three bid history 158 is arranged from the highest bid amount to the lowest amount bid. [0090] [0090]FIG. 7 illustrates a sample of a screen 160 that may be displayed to a bidder 30 who has not submitted a valid bid for lot three during the course of the auction 56 . At 162 , statistics regarding the market, or bids placed by other bidders 30 , are provided in connection with lots one and two only. The bidder 30 is provided with a bid submission area 164 , with which a bid may be formulated and submitted. The bidder 30 is also provided with a general status area 166 and a lot specific status area 168 , that includes information related to active lot three. It will be noted that the rank and total bids statistics are blank in FIG. 7 because the bidder 30 viewing FIG. 7 has not submitted a bid for lot three. At bid history area 170 , the bid history is provided if the bidder 30 viewing screen 160 had placed a valid bid. Because the bidder 30 has not placed a bid, however, a message stating “bid history is not available until you submit a valid bid in this lot” is displayed in the bid history area 170 . [0091] [0091]FIG. 8 illustrates a sample of a screen 180 that may be displayed to a bidder 30 who has submitted a valid bid for lot three during the course of the auction 56 . At lot listing 182 , statistics regarding the market or bids placed by other bidders 30 are provided in connection with lots one and two and three because the viewing bidder 30 has placed at least one valid bid for each of those lots. At bid submission area 184 , the bidder 30 is provided an area from which a bid may be formulated and submitted. At 186 , the bidder 30 is provided with a general status area and at 188 a status area for lot three, which is active because it is selected at 162 , is provided. It will be noted that the rank and total bids fields are displayed in FIG. 8 because the bidder 30 viewing FIG. 8 has submitted a valid bid for lot three. At 190 the bid history, including the amount of every bid placed and identifier for each bidder 30 is provided. EXAMPLE 1 [0092] The embodiment of the invention depicted in FIGS. 5 - 8 may also be illustrated by reference to Tables 1 through 5. In that embodiment, market feedback is provided to only those participants who have placed a valid bid. That prevents disingenuous participants from watching the auction 56 to gather pricing intelligence without placing a bid themselves and forces participants to take some risk by submitting a bid before they are able to view market feedback. That embodiment also discourages bidders 30 from waiting until the last moment to place a bid because no competitive information regarding the bid is available to a bidder 30 until that bidder 30 submits its first bid. [0093] Referring to the bidding activity shown in Table 1, at 1:04:00 PM, Bidders A, B, C, and D have submitted bids into the auction 56 , while Bidders E, F and G have not. Accordingly, in the current embodiment, market feedback would only be made available to Bidders A, B, C, and D at 1:04:00 PM, and those bidders 30 would view all bids placed by all bidders 30 at that time. Thus, the information provided to Bidders A, B, C, and D at 1:04:00 PM would appear as shown in Table 2. TABLE 2 1. Market Participants Only Bids vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14%  Bidder B 1:01:23 PM $664,000 $106,300 19.06%  Bidder C 1:01:28 PM $560,000  $2,300 0.41% 4 Bidder B 1:03:10 PM $559,000  $1,300 0.23% 3 Bidder D 1:02:50 PM $558,500    $800 0.14% 2 Bidder A 1:03:38 PM $558,300    $600 0.11% 1 [0094] Bidders E, F and G would not receive any market feedback at 1:04:00 PM. Thus, the information provided to Bidders E, F, and G at 1:04:00 PM would appear as shown in Table 3. TABLE 3 1. Market Participants Only Bids vs. Market Lead Bid Time Bid $ % Rank [0095] Again referring to Table 1, at 1:05:12 PM, Bidder E placed a bid of $557,700. As soon as that bid is submitted, Bidder E receives full feedback of all bids placed in the market. In this instance, Bidder E has placed a new market-leading bid, although this is not apparent to Bidder E until after the bid has been submitted. Thus, Bidder E and Bidders A, B, C, and D would see the bid history shown in Table 4 after the 1:05:12 PM bid has been submitted and Bidder E would realize lie has submitted the market-leading bid. TABLE 4 1. Market Participants Only Bids vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14%  Bidder B 1:01:23 PM $664,000 $106,300 19.06%  Bidder C 1:01:28 PM $560,000  $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000  $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500    $800 0.14% 3 Bidder A 1:03:38 PM $558,300    $600 0.11% 2 Bidder E 1:05:12 PM $557,700    $— 0.00% 1 [0096] In this embodiment, once a bidder 30 has placed a bid, that bidder 30 is entitled to continue to see all bid history for the remainder of the auction 56 regardless of whether they submit any additional bids. Hence, at the end of the auction 56 at 1:09:00 PM, Bidder E will view the bid history shown below in Table 5, even though Bidder E had not place any additional bids. TABLE 5 1. Market Participants Only Bids vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $128,000  23.62%  Bidder B 1:01:23 PM $664,000 $122,000  22.51%  Bidder C 1:01:28 PM $560,000 $18,000 3.32% Bidder B 1:03:10 PM $559,000 $17,000 3.14% Bidder D 1:02:50 PM $558,500 $16,500 3.04% 7 Bidder A 1:03:38 PM $558,300 $16,300 3.01% 6 Bidder E 1:05:12 PM $557,700 $15,700 2.90% 5 Bidder F 1:05:43 PM $557,500 $15,500 2.86% Bidder C 1:06:49 PM $552,000 $10,000 1.85% Bidder G 1:06:55 PM $549,000  $7,000 1.29% Bidder C 1:07:22 PM $546,800  $4,800 0.89% Bidder F 1:07:49 PM $546,400  $4,400 0.81% 4 Bidder C 1:08:02 PM $546,250  $4,250 0.78% 3 Bidder B 1:03:17 PM $545,000  $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000    $— 0.00% 1 [0097] It should be noted that in example one and the following examples, the term “rank” indicates rank of bidders. Alternately, rank may be based on bids such that the bid placed by Bidder C at 1:07:22 PM in Table 5 would be ranked fifth. EXAMPLE 2 [0098] In another embodiment, a bidder 30 will not view any market feedback unless the current best bid of that bidder 30 is within a group of “market leaders.” Whether a bid qualifies the submitting bidder 30 as a market leader may be determined in many ways including, for example, a bidder 30 may be a market leader when that bidder 30 places a bid that is within no more than a predetermined percentage behind the market-leading bid. For example, the bidder 30 may be provided with market feedback as long as the lowest bid of that bidder 30 is no more than 2% behind the market-leading bid. Alternately, a bid may be considered a market leader if the lowest bid of that bidder 30 ranks no more than a specified number of places behind the market-leading bid. For example, the bidder 30 may be provided with market feedback as long as the lowest bid of that bidder 30 is one of the top three bids. In yet another alternative, a bid may be considered a market leader if the lowest bid of that bidder 30 is within no more than a predetermined absolute value behind the market-leading bid; for example, no more than $10,000 behind the market-leading bid. [0099] In the market leader embodiments, bidders 30 may view market feedback only as long as their bid remains within the market-leading group of bids. The first time a bidder 30 submits a bid within the market-leading group, they will be able to view market feedback. Up until that point (or if a bidder 30 does not submit a bid at all), no market feedback will be provided to that bidder 30 . If, in the course of the auction 56 , a bidder 30 falls out of the market-leading group because other bidders 30 have exceeded the rank of bidder 30 , the market feedback may not be updated for that bidder 30 from the point in time at which that bidder 30 fell out of the market-leading group. That is, the market feedback will freeze at that point and will not be updated until that bidder 30 regains a market-leading position. In this example, if the bidder 30 places another bid and regains a market-leading position, the market feedback for that bidder 30 will be updated to include all bids placed to that point in time, including the bids placed while the bidder 30 was out of the market-leading group. Hence, a bidder 30 might gain, lose, and re-gain visibility to market feedback many times during the course of an auction 56 depending on the competitive interaction between all of the bidders 30 . [0100] The market leader format rewards the most aggressive bidders 30 with the most pricing information from the auction 56 and prevents non-participating or uncompetitive bidders 30 from learning pricing information. It limits the disclosure of final auction results to all but the most aggressive bidders 30 , decreasing the risk to the market leaders that valuable pricing information will “leak out” to a broader marketplace. The decision about how to define the market-leading group can be used by the auction coordinator 20 as a strategic signal to all bidders 30 about the intentions of the purchaser 10 with respect to awarding the business. E.g., defining market leaders as the top three bidders 30 might be used as a signal that the award will go to one of the top three bidders 30 . That might, in turn, drive more aggressive bidding by all bidders 30 . Even incumbents are encouraged to stay in the top three ranked bidders 30 to avoid the risk of being so far behind the leaders that the purchaser 10 can comfortably justify the switching costs of moving the business. [0101] [0101]FIG. 9 is a flow diagram 200 illustrating an embodiment of the present invention wherein access to market feedback is restricted to those bidders 30 who are market leaders. At 202 of the embodiment illustrated in FIG. 9, the auction 56 commences by accepting bids from the bidders 30 . At 204 , a bid is received from any bidder 30 participating in the auction 56 . At 206 , the processor determines which bidders 30 are market leaders based on predetermined conditions such as the differential market feedback technology and the differential market feedback rules. The processor may then set a flag identifying the market leading bidders 30 as such. [0102] At 208 through 224 , an example is provided of the bid participant segment wherein market feedback is provided only to market leading bidders 30 . In that example, “n” represents the number of bidders 30 that are permitted by the auction coordinator to participate in the auction 56 . At 208 , the processor checks to see whether Bidder one is a market leader. At 210 , market feedback is provided to Bidder one if Bidder one is a market leader and at 212 , market feedback is withheld from Bidder one if Bidder one is not a market leader. [0103] Similarly, at 214 , the processor checks to see whether Bidder two is a market leader. At 216 , market feedback is provided to Bidder two if Bidder two is a market leader and at 218 , market feedback is withheld from Bidder two if Bidder two is not a market leader. The processor will continue to consider the market leading status of each bidder 30 and provide market feedback to only those bidders 30 who are market leaders. At 220 , the processor checks to see whether the last bidder 30 (Bidder n) is a market leader. At 222 , market feedback is provided to Bidder n if Bidder n is a market leader and at 144 , market feedback is withheld from Bidder n if Bidder n is not a market leader. [0104] After the bid participant segment has been completed, the processor will determine whether the auction closing time has arrived at 226 . If the auction closing time has not arrived, the processor will return to 204 to receives any additional bids that have been received. Each time a new bid is received the processor will update the market leading status of the bidders 30 and provide market feedback to all market leaders. If the auction closing time has arrived, the auction 56 will close and no additional bids will be accepted. [0105] Consider again the sequence of bidding activity in Table 1, assuming this time that the market leader format is being used such that bidders 30 must to be within 2% of the market-leading bid to view bidding activity. At 1:04:00 PM, Bidder E does not receive any market feedback because Bidder E has not yet placed any bids. Thus, the view of the market by Bidder E at 1:04:00 PM, is as shown in Table 6. TABLE 6 2. Market Leaders Only Bids vs. Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted. [0106] At 1:05:12 PM, Bidder E places a bid of $557,700, which is a new market-leading bid. After that bid has been placed, Bidder E is provided all permitted market feedback Lip until that point including all the bidding activity that had not previously been provided to Bidder E. Bidder E would see the bid history shown in Table 7 after the 1:05:12 PM bid is received. TABLE 7 2. Market Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14%  Bidder B 1:01:23 PM $664,000 $106,300 19.06%  Bidder C 1:01:28 PM $560,000  $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000  $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500    $800 0.14% 3 Bidder A 1:03:38 PM $558,300    $600 0.11% 2 Bidder E 1:05:12 PM $557,700    $— 0.00% 1 [0107] Bidder E is in a position to continue to view all bids placed by all bidders 30 unless and until the current best bid of Bidder E falls more than 2% behind the market-leading bid. Thus, Table 8 illustrates the market feedback that is provided to Bidder E at 1:07:22 PM because at that time, the best bid of Bidder E is within 2% of the market leading bid. TABLE 8 2. Market Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $123,200  22.53%  Bidder B 1:01:23 PM $664,000 $117,200  21.43%  Bidder C 1:01:28 PM $560,000 $13,200 2.41% Bidder B 1:03:10 PM $559,000 $12,200 2.23% 7 Bidder D 1:02:50 PM $558,500 $11,700 2.14% 6 Bidder A 1:03:38 PM $558,300 $11,500 2.10% 5 Bidder E 1:05:12 PM $557,700 $10,900 1.99% 4 Bidder F 1:05:43 PM $557,500 $10,700 1.96% 3 Bidder C 1:06:49 PM $552,000  $5,200 0.95% Bidder G 1:06:55 PM $549,000  $2,200 0.40% 2 Bidder C 1:07:22 PM $546,800    $— 0.00% 1 [0108] In the example illustrated in FIG. 8, Bidders C, F, and G have all bid below the original bid placed by Bidder E. Bidder E has not responded with any additional bids and so now ranks in fourth place, $10,900 behind the current low bid placed by Bidder C. The bid submitted by Bidder E, however, is only 1.99% higher than that of Bidder C who holds the market-leading bid of $546,800 at 1:07:22 PM. [0109] However, consider what occurs at 1:07:49 PM when Bidder F places a new market-leading bid of $546,400 into the auction 56 . At that point in time, Bidder E's current best bid is $11,300 or 2.07% behind the market-leading bid. Because the price differential between Bidder E and the market-leading bid is more than the 2% differential required to stay within the market-leading group of bidders 30 , Bidder E receives one final update of bid history alerting Bidder E to the fact that no further feedback will be made available to Bidder E until Bidder E submits a lower bid within 2% of the current low bid. Thus, Table 9 illustrates the market feedback that is provided to Bidder E at 1:07:49 PM because at that time, the best bid of Bidder E is no longer within 2% of the market leading bid. TABLE 9 2. Market Leaders Only Bidder Bid Time Bid Bidder A 1:02:45 PM $670,000 Bidder B 1:01:23 PM $664,000 Bidder C 1:01:28 PM $560,000 Bidder B 1:03:10 PM $559,000 Bidder D 1:02:50 PM $558,500 Bidder A 1:03:38 PM $558,300 Bidder E 1:05:12 PM $557,700 Bidder F 1:05:43 PM $557,500 Bidder C 1:06:49 PM $552,000 Bidder G 1:06:55 PM $549,000 Bidder C 1:07:22 PM $546,800 [0110] After 1:07:49 PM, Bidder E may only view more bid history if Bidder E places a new lower bid within 2% of the market-leading bid. In this example, while the bidding continued until 1:08:44 PM, Bidder E did not re-bid at any time so Bidder E did not receive any further feedback about the market-leading bidding activity in the auction 56 . [0111] In the example illustrated in Tables 7-9, Bidder E did not receive updates about rank or the differential (in dollars or percentage) from the market leading bid after 1:07:22 PM. That prevents Bidder E from learning any more information about recent market activity. Alternative implementations of the format illustrated in Tables 7-9 could allow rank and/or differentials information to be continuously updated depending on the degree to which the auction coordinator 20 wishes to limit disclosure of market leading bidding activity to non-market leaders. EXAMPLE 3 [0112] We will now consider how the same auction 56 will be viewed by Bidder E if the market leader format is used such that bidders 30 had to be ranked within the top three in order to view bidding activity. Again, as shown in Table 10, at 1:04:00 PM, Bidder E would not receive any market feedback because Bidder E has not placed bid. TABLE 10 3. Market Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted. [0113] At 1:05:12 PM, Bidder E places a bid of $557,700, which is a new market-leading bid such that Bidder E is ranked first. Because that rank is at least third, Bidder E is entitled to view all bid history Up until that point. Bidder E, therefore, is provided with the history shown in Table 11. TABLE 11 3. Market Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14%  Bidder B 1:01:23 PM $664,000 $106,300 19.06%  Bidder C 1:01:28 PM $560,000  $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000  $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500    $800 0.14% 3 Bidder A 1:03:38 PM $558,300    $600 0.11% 2 Bidder E 1:05:12 PM $557,700    $— 0.00% 1 [0114] At 1:05:12 PM, Bidder E is in a position to continue to view all bids placed by all bidders 30 unless and until the current best bid of Bidder E falls into fourth or worse place. Bidder E, therefore, sees the market feedback illustrated in Table 12 at 1:06:49 PM. TABLE 12 3. Market Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $118,000 21.38%  Bidder B 1:01:23 PM $664,000 $112,000 20.29%  Bidder C 1:01:28 PM $560,000  $8,000 1.45% Bidder B 1:03:10 PM $559,000  $7,000 1.27% 6 Bidder D 1:02:50 PM $558,500  $6,500 1.18% 5 Bidder A 1:03:38 PM $553,300  $6,300 1.14% 4 Bidder E 1:05:12 PM $557,700  $5,700 1.03% 3 Bidder F 1:05:43 PM $557,500  $5,500 1.00% 2 Bidder C 1:06:49 PM $552,000 0.00% 1 [0115] At 1:06:49 PM, Bidders C and F have submitted bids below that of Bidder E. Bidder E has not responded with any additional bids and so now ranks third, $5,700 behind the current low bid placed by Bidder C. Because Bidder E still ranks in the top three bidders 30 , Bidder E is able to continue to view all current market feedback. [0116] However, at 1:06:55 PM when Bidder G submits a new market-leading bid of $549,000. Bidder E's current best bid is ranked behind three other participants: Bidder G at $549,000, Bidder C at $552,000, and Bidder F at $557,500. That places Bidder E in fourth place overall and puts Bidder E outside of the market leaders as defined for this particular auction 56 . Bidder E, therefore, receives one final update of bid history alerting Bidder E to the fact that no further feedback will be made available to Bidder E until Bidder E submits a bid low enough to place E within the top three bidders 30 once again. The market feedback provided to Bidder E after the 1:06:55 PM bid by Bidder G is shown in Table 13. TABLE 13 3. Market Leaders Only Bidder Bid Time Bid Bidder A 1:02:45 PM $670,000 Bidder B 1:01:23 PM $664,000 Bidder C 1:01:28 PM $560,000 Bidder B 1:03:10 PM $559,000 Bidder D 1:02:50 PM $558,500 Bidder A 1:03:38 PM $558,300 Bidder E 1:05:12 PM $557,700 Bidder F 1:05:43 PM $557,500 Bidder C 1:06:49 PM $552,000 [0117] After 1:06:49 PM when Bidder E fell to the fourth highest bidder 30 , Bidder E will no longer receive market feedback unless Bidder E places a new lower bid that raises Bidder E to at least the rank of fourth. It is noteworthy that compared to the market leader format of the previous example, which was based on a 2% differential, Bidder E lost access to market feedback earlier in the Example 3 of sequence of bidding activity because of the difference in definition of a market leader. EXAMPLE 4 [0118] The next example illustrates how the same auction 56 is viewed by Bidder E when the market leader format is used such that bidders 30 must be within $10,000 of the current low bid to view bidding activity. Again, at 1:04:00 PM, Bidder E does not receive any market feedback because Bidder E has not placed a bid, as shown in Table 14. TABLE 14 4. Market Leaders Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted. [0119] At 1:05:12 PM, Bidder E places a bid of $557,700, which is a new market-leading bid. That entitles Bidder E to view all bid history up until that point. Bidder E would, therefore, see the bid history shown in Table 15. TABLE 15 4. Market Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14%  Bidder B 1:01:23 PM $664,000 $106,300 19.06%  Bidder C 1:01:28 PM $560,000  $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000  $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500    $800 0.14% 3 Bidder A 1:03:38 PM $558,300    $600 0.11% 2 Bidder E 1:05:12 PM $557,700    $— 0.00% 1 [0120] Once Bidder E has placed a bid that is within $10,000 of the lowest bid, such as the market leading bid of $557,000 placed at 1:05:12 PM, Bidder E will receive market feedback related to all bids placed by all bidders 30 unless and until the current best bid of Bidder E falls more than $10,000 behind the market-leading bid. Thus, the market feedback provided to Bidder E at 1:06:55 PM is shown in Table 16. TABLE 16 4. Market Leaders Only Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $121,000  22.04%  Bidder B 1:01:23 PM $664,000 $115,000  20.95%  Bidder C 1:01:28 PM $560,000 $11,000 2.00% Bidder B 1:03:10 PM $559,000 $10,000 1.82% 7 Bidder D 1:02:50 PM $558,500  $9,500 1.73% 6 Bidder A 1:03:38 PM $558,300  $9,300 1.69% 5 Bidder E 1:05:12 PM $557,700  $8,700 1.58% 4 Bidder F 1:05:43 PM $557,500  $8,500 1.55% 3 Bidder C 1:06:49 PM $552,000  $3,000 0.55% 2 Bidder G 1:06:55 PM $549,000    $— 0.00% 1 [0121] At 1:06:55 PM Bidders C, F, and G have all bid below the original bid placed by Bidder E. Bidder E has not responded with any additional bids and so now ranks in fourth place, 1.58% behind the current low bid placed by Bidder G. There is, however, only a differential of $8,700 between Bidder E's current best bid of $557,700 and the market-leading bid of $549,000 submitted by Bidder G. [0122] At 1:07:22 PM, Bidder C places a new market-leading bid of $546,800 into the auction 56 . At that point in time, the current best bid of Bidder E is $10,900 or 1.99% behind the market-leading bid. $10,900 is more than the $10,000 differential required to stay within the market-leading group of bidders 30 . Accordingly, Bidder E receives one final update of bid history alerting Bidder E to the fact that no further feedback will be made available until Bidder E submits a lower bid that is within $10,000 of the current low bid, as is shown in Table 17. TABLE 17 4. Market Leaders Only Bidder Bid Time Bid Bidder A 1:02:45 PM $670,000 Bidder B 1:01:23 PM $664,000 Bidder C 1:01:28 PM $560,000 Bidder B 1:03:10 PM $559,000 Bidder D 1:02:50 PM $558,500 Bidder A 1:03:38 PM $558,300 Bidder E 1:05:12 PM $557,700 Bidder F 1:05:43 PM $557,500 Bidder C 1:06:49 PM $552,000 Bidder G 1:06:55 PM $549,000 [0123] As with the previously discussed market leader format examples, Bidder E no longer receives market feedback after the lowest bid of Bidder E falls out of the required market-leading range. Note that compared to the market leader format based on the 2% differential or the top three ranking, Bidder E drops out at a different stage in the sequence of bidding activity when the dollar differential method is utilized. [0124] After falling from the market lead based on the dollar differential between the best current bid of Bidder E and the market leading bid, Bidder E may only view more bid history if Bidder E places a new bid low enough to put Bidder E within $10,000 of the market leading bid. In the case illustrated in this example, while the bidding activity continued until 1:08:44 PM, Bidder E did not re-bid at any time and so Bidder E did not receive any further feedback about the market-leading bidding activity in the auction 56 . EXAMPLE 5 [0125] Market feedback may also be provided in combination such as, for example, providing a bidder 30 with the current rank of that bidder 30 and the next lowest bid. Such a format will be referred to herein as a “next horse” format. By using the next horse format, each bidder 30 may be given information regarding where it stands in the overall bidding and how much its bid must be modified to move up one place in the ranking. The bidder 30 may thus gain more information each time it places a bid that is below that of the next ranked bidder 30 . The bidder 30 is therefore encouraged to place additional bids and actively participate in the auction 56 , but is not provided with information regarding the lowest bids unless that bidder 30 places a bid that is competitive with the those lowest bids. In that way, not only are bidders 30 encouraged to participate actively in the auction 56 , but low bid information is also withheld from those bidders 30 who are not willing to participate actively and competitively in the auction 56 . [0126] Thus, in the embodiment considered in this example, the only feedback a particular subject bidder 30 will receive throughout the entire auction 56 is the rank of the current bidder 30 and the value of the bid that is one better than the best bid submitted by the bidder 30 . Also in this example, each bidder 30 must submit at least one bid before that bidder 30 will receive any market feedback. [0127] [0127]FIG. 10 is a flow diagram 300 illustrating an embodiment of the present invention utilizing the next horse format in combination with the requirement that at least one bid must be placed before any information is divulged to a bidder 30 . The example provided assumes that a computer processor is executing a set of instructions that perform the steps, however, it will be recognized by one skilled in the art that the instructions may be carried out by any known method. At 302 , the auction 56 is commenced and bids are accepted from the bidders 30 . The auction 56 normally begins at a scheduled time that is prearranged between the auction coordinator 20 , the purchaser 10 and the bidders 30 . At 304 , a bid is received from a bidder 30 . That bid may be a bid that is created by a bidder 30 and submitted to the data processing network 77 from the client machine 72 by way of the communications network 73 . At 306 , a determination is made as to whether each bidder 30 has qualified as a bid participant by submitting at least one qualified bid. At 308 , the rank of each bidder 30 is determined. At 310 , each bidder 30 that is a bid participant is provided with the appropriate market feedback which, in this example, includes information related to the best bid submitted by the subject bidder and information related to the bidder ranked one above the current bidder. After providing the appropriate market feedback to each bidder 30 , the processor will determine whether the auction closing time has arrived at 312 . If the auction closing time has not arrived, the processor will return to 304 to receive additional bids. If the auction closing time has arrived, the auction 56 will close and no additional bids will be accepted. [0128] FIGS. 11 - 16 illustrate sample screens that are displayed for various participants in a particular auction 56 utilizing the next horse format described in connection with FIG. 10. Each of screens 11 - 16 were captured during the same auction 56 after the bids depicted on FIG. 11 were submitted and before any other bids were submitted. Thus, screens 11 - 16 illustrate the market feedback that is provided to various participants in a single next horse format auction 56 during a common time period. FIG. 11 illustrates a sample of a screen 350 that is displayed to the purchaser 10 . At 352 , a lot listing is provided that contains statistics for three lots of transportation services that are being auctioned. The first lot is highlighted and is, therefore, active in other portions of the screen 350 . At 354 , statistics for all three lots are displayed and at 356 , additional statistics for lot one are displayed. A bid history 358 , containing a listing of bids received for lot one is also displayed. [0129] [0129]FIG. 12 illustrates a sample of a screen 360 that is displayed to a bidder 30 who has not submitted a valid bid for lot one during the course of the auction 56 . A lot listing 362 is provided to display market feedback related to the next lowest bid. No statistics relating to other bidders 30 are displayed for any of the three lots, indicating that a valid bid has not been placed by the viewing bidder 30 . Fields for Next Place Bid 363 and My vs. Next 365 are provided in the lot listing 362 . Those fields are necessarily different than the fields provided to the purchaser 10 in FIG. 11 or a bidder 30 in the auction 56 illustrated in FIGS. 6 - 8 , because it is important that the purchaser 10 be aware of all bids including the market leading bid and because it has been determined that bidders 30 in the example illustrated in FIGS. 11 - 16 are to be provided less market feedback than bidders 30 in the example illustrated in FIGS. 6 - 8 . Also, unlike the lot listing 162 of the screen 160 illustrated in FIG. 7, the lot listing 362 of FIG. 12 does not include a “Best Offering” field. The “Best Offering” field, which appears in FIGS. 7 and 8, may not be utilized in the embodiment illustrated in FIGS. 11 - 16 because, for example, that embodiment does not provide for bidding of different options related to each lot. Best offering is furthermore an option that may be utilized or not utilized in any of the embodiments discussed herein. [0130] A bid area 364 is provided from which a bid may be submitted. Within that bid area 364 are a number of buttons, including a disabled take next button 367 which will be discussed further hereinafter. Other buttons for submitting a bid and reloading the last bid submitted are also provided in the bid area 364 . At 366 , the bidder 30 is provided with a general status area and at 368 , a status area for the active lot is provided. Within the active lot status area 368 , the rank of the viewing bidder is not displayed in the “My Rank” field 370 because the viewing bidder has not yet submitted a valid bid for lot one. Unlike the active lot status area 168 of FIG. 7, the active lot status area 368 of FIG. 12 does not include a total bid field. That is because the total number of bids is not a piece of market feedback that is provided in the embodiment of the next horse format of this example. A bid history area 372 provides relevant bid history to the viewing bidder 30 if that viewing bidder 30 has placed a valid bid for the active lot. The viewing bidder 30 of screen 360 , however, has not placed a valid bid for the active lot and, therefore, a message stating “bid history is not available until you submit a valid bid in this lot” is displayed in the bid history area 372 . [0131] [0131]FIG. 13 illustrates a sample screen 380 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked fourth in the bidding. A lot listing 382 is provided that includes values in the “Next Place Bid” field 363 and the “My vs. Next” field 365 for lot one. Lot one is furthermore active in the remainder of the screen 380 because lot one is the highlighted lot in the lot listing 382 . Fields 363 and 365 are displayed because the bidder 30 viewing the screen 380 of FIG. 13 has submitted at least one valid bid for lot one. At 384 , the bid area is displayed and the take next button 367 is enabled as indicated by the dark lettering in the take next button 367 . At 386 , a general status area is provided for all lots currently being auctioned. An active lot status area 388 is provided and includes market feedback regarding the rank of the viewing bidder 30 with regard to lot one because that bidder 30 has placed a valid bid for lot one, which is the active lot. A historic bid listing, applicable to the viewer of screen 380 , is provided in the bid history area 390 . That bid history includes market feedback for the lowest price bid by the viewing bidder 30 and all higher bids. In keeping with the next horse format, the bid history area 390 could provide varying data. For example, market feedback related to the next better ranked bidder 30 could be provided in the bid history area 390 since market feedback related to that bidder 30 is already provided in the lot listing 382 . Alternately, market feedback related to previously submitted higher bids may or may not be provided in the bid history area 390 when using the next horse format or any other format discussed herein. [0132] [0132]FIG. 14 illustrates a sample screen 400 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked fifth in the bidding. A lot listing 402 is provided that includes values in the “Next Place Bid” field 363 and the “My vs. Next” field 365 for lot one. Lot one is furthermore active in the remainder of the screen 400 because lot one is the highlighted lot in the lot listing 402 . Fields 363 and 365 are displayed because the bidder 30 viewing the screen 400 of FIG. 14 has submitted at least one valid bid for lot one. A bid area 404 is displayed and the take next button 367 is enabled as indicated by the dark lettering in the take next button 367 . At 406 , a general status area is provided for all lots currently being auctioned. At 408 , an active lot status area is provided which includes market feedback regarding the rank of the viewing bidder with regard to lot one 30 because that bidder 30 has placed a bid for active lot one. A listing of historic bids that is applicable to the viewer of screen 400 is provided in the bid history area 410 . That bid history includes market feedback for the lowest price bid by the viewing bidder 30 and all higher bids. Thus, the bid history area 410 of FIG. 14 does not include the bid by the fourth ranked bidder that is shown in the bid history area 390 of FIG. 13 because the viewer of screen 400 has a worse ranking than the viewer of screen 380 . [0133] [0133]FIG. 15 illustrates a sample screen 420 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked second in the bidding. A lot listing 422 is provided that includes values in the “Next Place Bid” field 363 and the “My vs. Next” field 365 for lot one. Lot one is furthermore active in the remainder of the screen 420 because lot one is the highlighted lot in the lot listing 422 . Fields 363 and 365 are displayed because the bidder 30 viewing the screen 420 of FIG. 15 has submitted at least one valid bid for lot one. A bid area 404 is displayed and includes an enabled take next button 367 , as indicated by the dark lettering in the take next button 367 . A general status area 426 is provided for all lots currently being auctioned and an active lot status area 428 is provided which includes market feedback regarding the rain of the viewing bidder 30 with regard to lot one because that bidder 30 has placed a bid for active lot one. A bid history applicable to the viewer of screen 420 is provided in the bid history area 430 . That bid history, like that of the other bidders 30 who have submitted a valid bid in the active lot, includes market feedback for the lowest price bid by the viewing bidder 30 and all higher bids. Thus, the bid history area 430 of FIG. 15 includes all bids by the second and worse ranked bidders 30 and the lot listing 422 provides market information for the first place bidder. [0134] [0134]FIG. 16 illustrates a sample screen 450 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked first in the bidding. A lot listing 452 is provided that includes values in the “Next Place Bid” field 363 and the “My vs. Next” field 365 for lot one. Lot one is furthermore active in the remainder of the screen 450 because lot one is the highlighted lot in the lot listing 452 . Fields 363 and 365 are displayed because the bidder 30 viewing the screen 450 of FIG. 16 has submitted at least one valid bid for lot one. A bid area 454 is displayed and the take next button 367 is enabled as indicated by the dark lettering in the take next button 367 . At 456 , a general status area is provided for all lots currently being auctioned. At 458 , an active lot status area is provided which includes market feedback regarding the rank of the viewing bidder 30 because that bidder 30 has placed a valid bid for active lot one. A bid history applicable to the viewer of screen 450 is provided in the bid history area 460 . That bid history, like that of the other bidders 30 who have submitted a valid bid, includes market feedback for the lowest amount bid by the viewing bidder 30 and all higher bids. Thus, the bid history area 460 of FIG. 16 includes all bids submitted by all bidders 30 . [0135] Another example of market feedback that may be provided to a bidder 30 using a next horse format is as follows: after placing its first bid, a bidder 30 in third place will be informed of (i) the value of its current best bid; (ii) the fact that it is ranked third in the auction 56 ; and (iii) the value of the bid placed by the second ranked bidder 30 . Similarly, the bidder 30 in second place will know (i) the value of its current best bid; (ii) the fact that it is ranked second in the auction 56 ; and (iii) the value of the bid placed by the first ranked bidder 30 . [0136] The only way for a bidder 30 to receive market feedback concerning more competitive bids is to place a bid that improves their competitive position in the auction 56 . Consider, for example, a situation, wherein Bidder A is ranked fourth and Bidder B is ranked third. If Bidder A places a bid that is lower than the that of Bidder B, Bidder A becomes the third ranked bidder 30 and Bidder B becomes the fourth ranked bidder. Bidder A is then permitted to view the new third place bid that Bidder A just submitted, as well as the second placed bid. That format precludes all but the most aggressive bidders 30 from visibility to true market pricing. In fact, the only participants that will know the value of the first placed bid will be the first and second placed bidders 30 . [0137] The next horse format may be a particularly risky format for an incumbent bidder 30 . Without any real knowledge of how far from the bottom of the market they need to be, an incumbent is taking a substantial risk by not being in the top 1 or 2 bidders 30 . EXAMPLE 6 [0138] Consider again the sequence of bidding activity in Table 1, assuming this time that the auction 56 was set up to use a next horse format that provides only information regarding the best bid of that bidder 30 and the next better ranked bidder 30 and does not provide a listing of worse bids that have been placed. At 1:04:00 PM, Bidder E would not receive any market feedback because Bidder E has not yet placed any bids. Thus, Bidder E is provided with no market feedback at 1:04:00 PM as is shown in Table 18. TABLE 18 5. Next Horse Bid vs. Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted. [0139] At 1:07:49 PM, Bidder E has placed a bid and is in fourth place behind bidders F, C and G. The full bid history (not visible to any of the bidders 30 in this example) is repeated in Table 19. TABLE 19 5a. Next Horse (1:07:49) Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $123,600  22.62%  Bidder B 1:01:23 PM $664,000 $117,600  21.52%  Bidder C 1:01:28 PM $560,000 $13,600 2.49% Bidder B 1:03:10 PM $559,000 $12,600 2.31% 7 Bidder D 1:02:50 PM $558,500 $12,100 2.21% 6 Bidder A 1:03:38 PM $558,300 $11,900 2.18% 5 Bidder E 1:05:12 PM $557,700 $11,300 2.07% 4 Bidder F 1:05:43 PM $557,500 $11,100 2.03% Bidder C 1:06:49 PM $552,000  $5,600 1.02% Bidder G 1:06:55 PM $549,000  $2,600 0.48% 3 Bidder C 1:07:22 PM $546,800   $400 0.07% 2 Bidder F 1:07:49 PM $546,400 — 0.00% 1 [0140] In the next horse format of this example at 1:07:49 PM, Bidder E is informed that it is currently in fourth place, and that the third placed bidder 30 has placed a bid of $549,000, which is $8,700 or 1.58% lower than E's current best bid of $557,700 as is shown in Table 20. TABLE 20 5a. Next Horse (Bidder E) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder E 1:05:12 PM $557,700 $8,700 1.58% 4 Bidder G 1:06:55 PM $549,000 3 [0141] At 1:07:49 PM, Bidder G is informed that it is currently in third place, and that the second ranked bidder has placed a bid of $546,800, which is $2,200 or 0.40% lower than Bidder G's current best bid of $549,000 as is shown in Table 21. TABLE 21 5a. Next Horse (Bidder G) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:06:55 PM $549,000 $2,200 0.40% 3 Bidder C 1:07:22 PM $546,800 2 [0142] At 1:07:49 PM, Bidder C is informed that it is currently in second place, and that the first placed bidder 30 has placed a bid of $546,400, which is $400 or 0.07% lower than Bidder C's current best bid of $546,800, as is shown in Table 22. TABLE 22 5a. Next Horse (Bidder C) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:07:22 PM $546,800 $400 0.07% 2 Bidder F 1:07:49 PM $546,400 1 [0143] At 1:07:49 PM, Bidder F is informed that it is currently in first place with a bid of $546,400, as is shown in Table 23. TABLE 23 5a. Next Horse (Bidder F Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $— 0.00% 1 [0144] At 1:08:02 PM, Bidder C places a new market leading bid moving Bidder C up in rank from second to first place. The full bid history (not visible to any of the bidders 30 in this example) is shown in Table 24. TABLE 24 5b. Next Horse (1:08:02) Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $123,750  22.65%  Bidder B 1:01:23 PM $664,000 $117,750  21.56%  Bidder C 1:01:28 PM $560,000 $13,750 2.52% Bidder B 1:03:10 PM $559,000 $12,750 2.33% 7 Bidder D 1:02:50 PM $558,500 $12,250 2.24% 6 Bidder A 1:03:38 PM $558,300 $12,050 2.21% 5 Bidder E 1:05:12 PM $557,700 $11,450 2.10% 4 Bidder F 1:05:43 PM $557,500 $11,250 2.06% Bidder C 1:06:49 PM $552,000  $5,750 1.05% Bidder G 1:06:55 PM $549,000  $2,750 0.50% 3 Bidder C 1:07:22 PM $546,800   $550 0.10% Bidder F 1:07:49 PM $546,400   $150 0.03% 2 Bidder C 1:08:02 PM $546,250    $— 0.00% 1 [0145] Bidder C will, therefore, see that it is ranked first at 1:08:02 PM with a bid of $546,250, as is shown in Table 25. TABLE 25 5b. Next Horse (Bidder C) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:08:02 PM $546,250 $— 0.00% 1 [0146] Bidder F, who has been displaced from first place at 1:08:02 PM, will see that it is in second place at 1:08:02 PM, and that the bidder ranked first has placed a bid of $546,250, which is $150 or 0.03% lower than the best bid of $546,400 placed by Bidder F, as is shown in Table 26. TABLE 26 5b. Next Horse (Bidder F) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $150 0.03% 2 Bidder C 1:08:02 PM $546,250 1 [0147] At 1:08:02 PM, Bidder G remains in third place but can see that the second placed bidder is now at $546,400, which is $2,600 or 0.48% lower than G's best bid of $549,000. Bidder G thus learns that activity between the first and second placed bidders has increased the distance between Bidder G and the market-leading bid, as is shown in Table 27. TABLE 27 5b. Next Horse (Bidder G) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:06:55 PM $549,000 $2,600 0.48% 3 Bidder F 1:07:49 PM $546,400 2 [0148] Next, consider the situation at 1:08:17 PM. Bidder B (previously in seventh place) places a new market-leading bid of $545,000. Bidder B is now ranked first. The full bid history up until 1:08:17 PM (not visible to any of the bidders 30 in this example) is shown in Table 28. TABLE 28 5c. Next Horse (1:08:17) Bid vs. Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $125,000  22.94% Bidder B 1:01:23 PM $664,000 $119,000  21.83% Bidder C 1:01:28 PM $560,000 $15,000 2.75% Bidder B 1:03:10 PM $559,000 $14,000 2.57% Bidder D 1:02:50 PM $558,500 $13,500 2.48% 7 Bidder A 1:03:38 PM $558,300 $13,300 2.44% 6 Bidder E 1:05:12 PM $557,700 $12,700 2.33% 5 Bidder F 1:05:43 PM $557,500 $12,500 2.29% Bidder C 1:06:49 PM $552,000  $7,000 1.28% Bidder G 1:06:55 PM $549,000  $4,000 0.73% 4 Bidder C 1:07:22 PM $546,800  $1,800 0.33% Bidder F 1:07:49 PM $546,400  $1,400 0.26% 3 Bidder C 1:08:02 PM $546,250  $1,250 0.23% 2 Bidder B 1:08:17 PM $545,000    $— 0.00% 1 [0149] At 1:08:17 PM, Bidder C, who has been displaced from first place, will see that it are now in second place, and that the first placed bidder has placed a bid of $545,000, which is $1,250 or 0.23% lower than C's best bid of $546,250, as is shown in Table 29. TABLE 29 5c. Next Horse (Bidder C) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:08:02 PM $546,250 $1,250 0.23% 2 Bidder B 1:08:17 PM $545,000 1 [0150] Bidder F has been displaced from second place and now ranks third. Although the ranking has changed, in all other respects F sees the same feedback. The second placed bidder 30 is at $546,250, which is $150 or 0.03% lower than Bidder F's best bid of $546,400, as is shown in Table 30. TABLE 30 5c. Next Horse (Bidder F) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $150 0.03% 3 Bidder C 1:08:02 PM $546,250 2 [0151] At 1:08:17 PM, Bidder G faces a situation similar to that of Bidder F. Bidder G has been displaced from third place and now ranks fourth overall, but the feedback with respect to the next placed bidder is the same. The third placed bidder is at $546,400, which is $2,600 or 0.48% lower than G's best bid of $549,000, as is shown in Table 31. TABLE 31 5c. Next Horse (Bidder G; 1:08:17) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:06:55 PM $549,000 $2,600 0.48% 4 Bidder F 1:07:49 PM $546,400 3 [0152] At 1:08:44 PM, Bidder G decides to lower its bid by $7,000. That places Bidder G in first place. The full bid history (not visible to any of the bidders 30 in this example) is shown in Table 32. TABLE 32 5d. Next Horse (1:08:44) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $128,000  23.62%  Bidder B 1:01:23 PM $664,000 $122,000  22.51%  Bidder C 1:01:28 PM $560,000 $18,000 3.32% Bidder B 1:03:10 PM $559,000 $17,000 3.14% Bidder D 1:02:50 PM $558,500 $16,500 3.04% 7 Bidder A 1:03:38 PM $558,300 $16,300 3.01% 6 Bidder E 1:05:12 PM $557,700 $15,700 2.90% 5 Bidder F 1:05:43 PM $557,500 $15,500 2.86% Bidder C 1:06:49 PM $552,000 $10,000 1.35% Bidder G 1:06:55 PM $549,000  $7,000 1.29% Bidder C 1:07:22 PM $546,800  $4,800 0.89% Bidder F 1:07:49 PM $546,400  $4,400 0.81% 4 Bidder C 1:08:02 PM $546,250  $4,250 0.78% 3 Bidder B 1:08:17 PM $545,000  $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000    $— 0.00% 1 [0153] At 1:08:44 PM, Bidder G is provided with the market feedback shown in Table 33. TABLE 33 5d. Next Horse (Bidder G; 1:08:44) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:08:44 PM $542,000 $— 0.00% 1 [0154] Thus, at 1:08:44 PM Bidder B has been displaced from first place. Bidder B will, therefore, see that it is now ranked second and that the first placed bidder has placed a bid of $542,000, which is $3,000 or 0.55% lower than B's bid of $545,000. The market feedback provided to Bidder B at 1:08:44 PM is illustrated in Table 34. TABLE 34 5d. Next Horse (Bidder B; 1:08:44) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder B 1:08:17 PM $545,000 $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000 1 [0155] At 1:08:44 PM, Bidder C sees the same feedback as before, except that the rank of Bidder C has now slipped from second to third place. Bidder C will, however, be advised that the second placed bidder is at $545,000, which is $1,250 or 0.23% lower than the lowest bid submitted by Bidder C, which is $546,250. The market feedback provided to Bidder C at 1:08:44 PM is illustrated in Table 35. TABLE 35 Next Horse (Bidder C; 1:08:44) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:08:02 PM $546,250 $1,250 0.23% 3 Bidder B 1:08:17 PM $545,000 2 [0156] At 1:08:44 PM, Bidder F would view the market feedback shown in Table 36 and the remaining bidders 30 would also be provided with market feedback according to the next horse format utilized in this example. TABLE 36 5d. Next Horse (Bidder F; 1:08:44) Bid vs. Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $150 0.03% 4 Bidder C 1:08:02 PM $546,250 3 [0157] Other combinations of market feedback may also be provided in connection with the next horse format. For example, as previously described, in certain embodiments of the next horse market feedback format, not only is information provided for the next better bid, information related to all worse bids is also provided. [0158] Auctions 56 , and particularly online auctions 56 , can be fast paced, requiring bidders 30 to make important decisions about whether to submit an additional bid to better that of another bidder 30 . In many auctions 56 bettering a bid placed by another bidder 30 may not be as simple as placing a bid that is one dollar less than that placed by the other bidder 30 . For example, to avoid the submission of many bids that better each other by very small amounts, purchasers 10 may require that bidders 30 place a minimum differential bid to better that of the next higher ranked bidder 30 , another higher ranked bidder 30 , or the market leading bidder 30 . [0159] Thus, for example, if Bidder A has placed a best bid of $ 52 , 000 in a reverse auction 56 , Bidder B has placed the next better ranked bid with a bid of $550,000, and the minimum differential bid required is $ 500 , then Bidder A would have to submit a bid of no more than $49,500 to move up one place in the ranking. Because bids are not always submitted in such round numbers and time allowed to calculate and place another bid, particularly near the closing of an auction 56 , can be short, it is beneficial to include in the auction 56 a facility for calculating and/or submitting the maximum amount that would place the bidder 30 at a desired rank. The present invention, therefore, may include one or more facilities for automatically calculating the maximum amount that may be bid to place a bidder 30 at a desired rank in a reverse auction. Of course, such a minimum differential may also be applied to a forward auction and a facility that adds the minimum differential to a better ranked bid would be equally applicable. EXAMPLE 7 [0160] In a certain embodiment of the invention, wherein the next horse format is utilized such that only the amount bid by the next better bidder 30 and current rankng is known to each bidder 30 , a “take next rank” facility may be provided in the auction software. That take next rank facility may take the form of a button that may be depressed or a selectable button that is displayed on the screen of the bidder 30 . An example of such a button is illustrated on FIGS. 12 - 16 at reference number 367 and is labeled “Take Next.” [0161] Selection of the take next rank button or a similar take higher rank button (not illustrated) may perform several functions including, for example, calculating of the maximum amount that must be bid to attain the next higher rank, and submitting that amount as a bid. [0162] Selection of the take next rank button or take higher rank button may alternately only calculate the maximum amount that must be bid to attain the next higher rank. In that format, the bidder 30 may have the amount required for the next bid provided quickly and accurately and then consider whether to place a bid equal to the calculated amount, place a bid for a lesser amount, or choose not to place a bid that moves that bidder 30 up to the next rank. [0163] A select higher rank facility may also or alternately be provided. In one embodiment, selection of the take higher rank button will calculate the maximum amount that must be bid to attain one selected higher rank. In another embodiment, the take higher rank button will calculate the maximum bid required to take all higher ranks. [0164] Referring to FIG. 12, the take next button 367 is dimmed indicating that the button is disabled and, therefore, may not be selected. The take next button 367 of FIG. 12 is disabled because the bidder 30 viewing the screen 360 of FIG. 12 has not yet submitted a valid bid for lot one which is selected in the lot listing 362 . The take next button 367 may be enabled for a bidder 30 that has not yet placed a bid, for example, to provide an amount that must be bid to overtake the lowest ranked bidder 30 . Enabling the take next button 367 for a non-participating bidder 30 , however, permits that non-participating bidder 30 to view market feedback related to the lowest bidder 30 . Thus, in the embodiment illustrated in FIG. 12, the viewing bidder 30 is not permitted to utilize the take next button 367 because the rules for that auction 56 are defined such that no market feedback is permitted to be viewed until a bidder 30 has placed a valid bid. Therefore, in the embodiment illustrated in FIG. 12, the viewing bidder 30 must place a bid prior to being permitted to utilize the take next button 367 . [0165] Referring to FIGS. 13 - 16 , the take next button 367 is displayed and enabled. In accordance with the rules that are employed in the embodiment illustrated in those Figures, the take next button 367 is enabled because the bidders 30 viewing the screens 380 , 400 , 420 , and 450 of those Figures are permitted to use the take next button 367 because they have submitted at least one bid for the active lot. The auction 56 displayed in FIGS. 11 - 16 is an index type auction 56 wherein the amount bid is added to a predetermined index price. Thus a bid of 10 . 00 might indicate a bid of 10.00% over the index price, while a bid of −0.30 might indicate a bid of 0.30% under the index price. Thus, the viewer of screen 380 , for example, may select the take next button by, for example using a mouse, keyboard, or touch screen. As may be seen in the lot listing 382 , the next better bid is 4.75 which is 4.25 less than the best bid submitted by the viewing bidder 30 . If, for example, the minimum differential for the auction 56 depicted on screen 380 is 0.1, then selection of the take next button 367 would provide a value of 4.65 which is equal to the value of the next better bid of 4.75 less the minimum differential of 0.10. EXAMPLE 8 [0166] Tables 37-41 illustrate a reserve price format of the invention that takes into consideration the setting of a reserve price as discussed hereinbefore. In that format, bidders 30 do not view any market feedback unless their current best bid is below the reserve price. That format rewards bidders 30 who have made a minimum commitment to pursue an award by bidding below the reserve price. Thus, no market feedback is made available to bidders 30 who have not submitted a bid below the reserve price threshold, thereby limiting or eliminating disclosure of price sensitive information to bidders 30 who merely watch the auction 56 without participating therein. The reserve price format, therefore, may beneficially be used to inform all participants that the reserve price is a serious threshold which bidders 30 must meet before the purchaser 10 is willing to consider an award of the business to a non-incumbent. The reserve price format also puts pressure on incumbents to at least meet the reserve price once other bidders 30 have bid below the reserve price. [0167] Referring again to the sequence of bidding activity in FIG. 1, the following example assumes that the auction 56 is taking place in the reserve price format and the reserve price is set at $555,000. At 1:06:00 PM the complete bid history (not visible to any bidder 30 in this example) is repeated below in Table 37. TABLE 37 6. Below Reserve Only (1.06:00 PM) Bid vs Reserve Bid vs. Market Lead Bidder Bid Time Bid Reserve $ % $ % Rank Bidder A 1:02:45 PM $670,000 $555,000 $115,000 20.72%  $112,500 20 18% Bidder B 1:01:23 PM $664.000 $555,000 $109,000 19.64%  $106,500 19.10% Bidder C 1:01:28 PM $560,000 $555,000 $ 5,000 0 90% $ 2,500 0.45% 6 Bidder B 1:03:10 PM $559,000 $555,000 $ 4,000 0.72% $ 1,500 0.27% 5 Bidder D 1:02:50 PM $558,500 $555,000 $ 3,500 0.63% $ 1,000 0.18% 4 Bidder A 1:03:38 PM $558,300 $555,000 $ 3,300 0.59% $   800 0.14% 3 Bidder E 1:05:12 PM $557,700 $555.000 $ 2,700 0.49% $   200 0.04% 2 Bidder F 1:05:43 PM $557,500 $555,000 $ 2,500 0 45% $  — 0.00% 1 [0168] Following Bidder E to illuminate the operation of the reserve price format, at 1:06:00 PM Bidder E has placed one bid of $557,700 at 1:05:12 PM. Since that bid is above the reserve price, Bidder E does not receive any feedback about the remainder of the bidding activity in the auction 56 , as shown in Table 38. TABLE 38 6. Below Reserve Only (Bidder E) Bid vs. Reserve Bidder Bid Time Bid Reserve $ % Bidder E 1:05:12 PM $557,500 $555,000 $2,700 0.49% [0169] As may be seen by reference to Table 1, Bidder E did not submit any further bids in the auction 56 , and so does not receive any further market feedback during the auction 56 . In contrast, at 1:06:00 PM Bidder F has submitted only one bid of $557,500. Like Bidder E, Bidder F will receive no market feedback at 1:06:00 PM because the lowest submitted bid of Bidder F is above the reserve price. Thus, at 1:06:00 PM, Bidder F would view the information provided in Table 39. TABLE 39 6. Below Reserve Only (Bidder F) Bid vs. Reserve Bidder Bid Time Bid Reserve $ % Bidder F 1:05:43 PM $557,500 $555,000 $2,500 0.45% [0170] However, unlike Bidder E, Bidder F submits a bid of $546,400 at 1:07:49 PM. That bid is below the reserve price of $555,000 and, accordingly, Bidder F sees the full bid history as shown below in Table 40 after the 1:07:49 PM bid is placed. At 1:07:49 PM, Bidder F is able to sec that it is ranked first, and also becomes aware through the market feedback that there are two other bidders 30 who are below reserve price and within $3,000 or 0.5% of the current best bid of Bidder F. Although the identity of the other participants is not visible in this example, Bidder F would also see that there are six other bidders 30 participating in the auction 56 and that a total of twelve bids have been placed thus far in the auction 56 . TABLE 40 6. Below Reserve Only (Bidder F) Bid vs Reserve Bid vs. Market Lead Bidder Bid Time Bid Reserve $ % $ % Rank Bidder A 1:02.45 PM $670,000 $555.000 $115,000 20.72% $123,600 22.62% Bidder B 1:01:23 PM $664,000 $555,000 $109,000 19.64% $117,600 21.52% Bidder C 1:01:28 PM $560,000 $555,000 $ 5,000 0 90% $ 13,600 2.49% Bidder B 1:03:10 PM $559,000 $555,000 $ 4,000 0.72% $ 12,600 2.31% 7 Bidder D 1:02:50 PM $558,500 $555,000 $ 3,500 0.63% $ 12,100 2.21% 6 Bidder A 1:03:38 PM $558,300 $555,000 $ 3,300 0.59% $ 11,900 2.18% 5 Bidder E 1:05:12 PM $557,700 $555,000 $ 2,700 0.49% $ 11,300 2.07% 4 Bidder F 1:05:43 PM $557,500 $555,000 $ 2,500 0.45% $ 11,100 2.03% Bidder C 1:06:49 PM $552,000 $555,000 $ (3,000) −0.54% $ 5,600 1.02% Bidder G 1:06:55 PM $549,000 $555,000 $ (6,000) −1.08% $ 2,600 0.48% 3 Bidder C 1:07:22 PM $546,800 $555,000 $ (8,200) −1.48% $   400 0.07% 2 Bidder F 1:07:49 PM $546,400 $555,000 $ (8,600) −1 55% $  — 0 00% 1 [0171] Bidder F is entitled to view the bid history, for the remainder of the auction 56 in this example, because Bidder F has submitted a bid less than the reserve price as required to see that market feedback. As may be seen by reference to Table 1, Bidder F does not submit any additional bids during the auction 56 and, thus, falls back to fourth place by the time the auction 56 ends at 1:08:44 PM. The market feedback that Bidder F will see at 1:08:44 PM is shown in Table 41. TABLE 41 6. Below Reserve Only (Bidder F) Bid vs Reserve Bid vs Market Lead Bidder Bid Time Bid Reserve $ % $ % Rank Bidder A 1:02:45 PM $670,000 $555,000 $115,000 20 72% $128,000 23.62% Bidder B 1:01:23 PM $664,000 $555,000 $109,000 19 64% $122,000 22 51% Bidder C 1:01:28 PM $560,000 $555,000 $ 5,000 0.90% $ 18,000 3.32% Bidder B 1:03:10 PM $559,000 $555,000 $ 4,000 0.72% $ 17,000 3.14% Bidder D 1:02:50 PM $558,500 $555,000 $ 3,500 0.63% $ 16,500 3.04% Bidder A 1:03:38 PM $558,300 $555,000 $ 3,300 0.59% $ 16,300 3.01% 6 Bidder E 1:05:12 PM $557,700 $555,000 $ 2,700 0.49% $ 15,700 2.90% 5 Bidder F 1:05:43 PM $557,500 $555,000 $ 2,500 0.45% $ 15,500 2.86% Bidder C 1:06:49 PM $552,000 $555,000 $ (3,000) −0 54% $ 10,000 1.85% Bidder G 1:06:55 PM $549,000 $555,000 $ (6,000) −1.08% $ 7,000 1.29% Bidder C 1.07:22 PM $546,800 $555,000 $ (8,200) −1.48% $ 4,800 0.89% Bidder F 1:07:49 PM $546,400 $555,000 $ (8,600) −1.55% $ 4,400 0.81% 4 Bidder C 1:08:02 PM $546,250 $555,000 $ (8,750) −1.58% $ 4,250 0.78% 3 Bidder B 1:08:17 PM $545,000 $555,000 $ (10,000) −1 80% $ 3,000 0.55% 2 Bidder G 1:08:44 PM $542,000 $555,000 $ (13,000) −2.34% $  — 0.00% 1 [0172] Other differential feedback technology and differential feedback rules could also be applied to such a reserve price formatted auction 56 . For example, rather than providing no market feedback to bidders 30 that have not bid below the reserve price, the auction 56 could provide limited market feedback to those bidders 30 and full market feedback to bidders 30 who have bid below reserve. The limited feedback might include, for example, rank only or bid history of all the bids placed by bidders 30 that are above the reserve price but not any of the bids below reserve price. In the latter example, a bidder 30 who has not placed a bid below the reserve price would lose access to market feedback from those bidders 30 bidding below the reserve price until that bidder 30 also places a bid below reserve price. [0173] In another embodiment, the market leader format may be combined with the reserve price format to provide additional incentive to bidders 30 to continue bidding aggressively after they have crossed the reserve price threshold. For example, bid history might only be visible to participants who (i) have bid below reserve price; and (ii) are ranked in, for example, the top three bidders 30 . [0174] Alternatively, bid history might be visible to all bidders 30 below reserve until there are at least, for example, three bidders 30 below that have placed bids below the reserve price. Once more than three bidders 30 have bid below the reserve price in that example, only the top three bidders 30 would continue to view the full bid history. [0175] While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. In particular, it should be noted that while the auction functions described above have been described in the context of downward pricing auctions, the auction functions can be equally applied to upward pricing auctions. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
A method and system for conducting an auction having at least two competing bidders is disclosed. The method includes receiving bid data from at least one bidder and providing the bid data to a bidder that meets a condition for receiving the bid data. An apparatus for determining a suggested bid value that surpasses a selected bid is also disclosed. The apparatus includes a computer readable medium having stored thereon instructions which, when executed by a processor, cause the processor to provide a user selectable facility which, when selected establishes the value of the selected bid, calculates the suggested bid value by subtracting a predetermined minimum differential value from the selected bid value, and conveys the suggested bid value to the user.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] Not Applicable.", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH [0002] Not Applicable.", "BACKGROUND OF THE INVENTION [0003] 1.", "Field of the Invention [0004] The disclosed invention relates generally to conducting auctions, and in particular to restricting access to market information in online electronic auctions.", "[0005] 2.", "Description of the Background [0006] Procurement and selling of supplies has traditionally involved high transaction costs.", "Particularly, the cost of information searching regarding suppliers and sellers and their goods and services has often been prohibitively high.", "The introduction of electronic commerce has introduced new methods of procurement and selling that lower some of the transaction costs associated with procurement.", "Online procurement, or business-to-business electronic commerce, matches purchasers and suppliers so that transactions can take place electronically.", "The terms “purchaser”", "and “buyer”", "are used interchangeably herein to describe the party that desires to purchase goods or services in an auction.", "The terms “supplier”", "and “bidder”", "are used interchangeably herein to describe the party that desires to sell goods or services in the auction.", "Three models for online procurement are catalog, buyer-bidding auction, and supplier-bidding auction.", "[0007] The “catalog”", "model of online procurement allows customers to obtain information regarding products and services from a single supplier, i.e., single-source catalogs.", "Early electronic catalogs were developed by individual suppliers to help customers obtain information about products provided by the developing supplier and order those products electronically.", "Customers, however, were often not satisfied with such single-source catalogs but rather preferred to compare a number of competing products to facilitate a comparison of features and pricing.", "Thus, certain suppliers began to include competitors'", "products on their systems.", "By offering competing products in one catalog, those suppliers created “electronic markets.”", "[0008] The electronic markets created by suppliers, however, could be biased toward the supplier offering the electronic market.", "Thus, unbiased electronic markets that promote competition were developed to further lower purchase prices.", "[0009] For standard products and services, third party market makers compiled databases of related products and services from various suppliers to provide a single market from which similar products and services may be compared and through which those goods and services may be purchased.", "Purchasers may, thus, access the database of such a third party market, view information and pricing information related to each desired product or service, and order the desired products and services in a single visit to the third party database.", "[0010] When many purchasers compete for the right to buy from one supplier, a buyer-bidding auction model is created.", "In a certain buyer-bidding auction, potential purchasers compete for a product or service by submitting one or more bids to a website operated by the buyer-bidding auction coordinator.", "After the bids have been received, the supplier may choose to accept the highest bid, thereby binding the high bidder to a contract for the sale of the product or service.", "[0011] The catalog and buyer-bidding auction types of electronic markets, however, do not work well in some situations.", "For example, if the required product is custom made for the purchaser, it is difficult for suppliers to publish a set price in advance for a catalog market.", "Likewise, it is difficult for purchasers to specify all of the details of the product they want to purchase in a buyer-bidding auction.", "[0012] Traditionally, when a company required a custom industrial product, procurement was made by a purchaser for the company who searched for potential suppliers and acquired custom price quotes from those suppliers for the needed custom product.", "The search process tended to be slow because suppliers had to be sought out and then negotiations had to take place.", "The search process also tended to be somewhat random because it often relied heavily on personal relationships between purchasers and suppliers.", "There were also significant costs associated with locating vendors, comparing products, negotiating, and paperwork preparation in a purchase decision.", "The cost of switching suppliers may also be prohibitive because of the cost of searching for other qualified suppliers.", "Thus, purchasers disadvantageously received price quotes from existing suppliers that were not the lowest price that could have been obtained by a more thorough supplier search.", "New suppliers were also placed at a disadvantage due to the difficulty and cost of marketing to purchasers who have existing suppliers.", "[0013] As an alternative, purchasers may use on-line auctions having prequalified bidders to save money.", "The assignee of the present application developed a system, wherein suppliers downwardly bid against one another to achieve the lowest market price in a supplier-bidding, auction.", "[0014] In a supplier-bidding auction, bid prices typically start high and move downward in a reverse-auction format as suppliers interact to establish a low price at the close of the auction.", "The auction marketplace is typically one-sided, i.e., one purchaser and many potential suppliers.", "Either goods or services may be purchased in an auction, and the goods may be of any type including, for example, office products, finished products, other products, parts, components, or materials.", "“Components”", "typically are fabricated tangible pieces or parts that are assembled into durable products.", "Example components include gears, bearings, appliance shelves, and door handles.", "“Materials”", "are often raw materials that may be purchased in bulk and that are further transformed into product.", "Example materials include corn syrup and sheet steel.", "[0015] Furthermore, industrial purchasers often desire to purchase more than one component at a time.", "They may purchase whole families of similar components or groups of components that are related to one another by, for example, the final product into which they are incorporated.", "As an example, a purchaser might purchase a given plastic knob in two different colors, or might purchase a nameplate in four different languages.", "Those parts may be so similar that it is only practical to purchase the parts from the same supplier because, for example, all of the knobs can be made using the same mold.", "Those items are therefore grouped into a single lot.", "Suppliers in industrial auctions may, therefore, be required to provide unit price quotes for all line items in a lot.", "[0016] The process for a supplier-bidding auction is described below with reference to FIGS. 1 and 2.", "FIG. 1 illustrates the functional elements and entities in a supplier-bidding auction 56 , while FIG. 2 is a diagram that identifies the tasks performed by each of the involved entities.", "[0017] The supplier-bidding auction model typically requires that the bidding product or service be defined by the purchaser 10 .", "An auction coordinator 20 may work with the purchaser 10 to prepare for and conduct an auction 56 and to define potential new supply relationships resulting from the auction 56 .", "[0018] In the example illustrated in FIG. 2, the purchaser 10 provides data to the coordinator 20 in the Initial Contact phase 102 of the auction 56 .", "The coordinator 20 then prepares a specification 50 for each desired product 52 .", "Once the product 52 is defined, potential suppliers 30 for the product 52 are identified.", "The coordinator 20 and purchaser 10 work together to compile a list of potential suppliers from suppliers already known to the purchaser 10 as well as suppliers recommended by the coordinator 20 .", "[0019] The purchaser 10 makes a decision regarding which potential suppliers 30 will receive invitations to the upcoming auction 56 .", "Suppliers 30 that accept auction invitations are then sent notices regarding the upcoming auction 56 .", "In certain situations, suppliers 30 may also receive software to install in preparation of participating in the auction 56 .", "[0020] In the RFQ phase 104 illustrated in FIG. 2, the coordinator 20 works with the purchaser 10 to prepare a Request for Quotation (“RFQ”) 54 .", "The coordinator 20 collects and maintains the RFQ data provided by purchaser 10 , and then publishes the RFQ 54 , and manages the published RFQ 54 .", "The RFQ 54 includes specifications 50 for all of the products 52 covered by the RFQ 54 .", "In the RFQ 54 , the purchaser 10 may aggregate products into job “lots.”", "The purchaser 10 may also separate unlike products into separate lots to best fit the needs of the purchaser 10 and the capabilities of suppliers 30 .", "Lots, therefore, may include such things as aggregations of similar parts or products that are desired to be purchased together.", "That type of aggregation allows suppliers 30 to bid on that portion of the business for which they are best suited.", "[0021] During the auction 56 , bids 58 may be placed on individual lots (and their constituent parts 52 ) within the RFQ 54 .", "While suppliers 30 may be required to submit actual unit prices for all line items, the competition in an auction 56 is generally based on the aggregate value bid for lots.", "The aggregate value bid for a lot depends upon the level and nix of line item bids and the quantity for each line item.", "Therefore, suppliers 30 may submit bids at the line item level, but compete on the lot level.", "[0022] In the Auction Administration phase 106 , the coordinator 20 coordinates the auction 56 and administers the auction setup and preparation.", "The coordinator 20 sends an RFQ 54 to each participating supplier 30 , and assists participating suppliers 30 to prepare for the auction 56 .", "[0023] In the Conduct Auction phase 108 , suppliers 30 submit bids 58 on the lots and monitor the progress of the bidding by the participating suppliers 30 .", "The coordinator 20 assists, observes, and administers the auction 56 .", "[0024] When the bidding period is over, the auction 56 enters the Administration of Auction Results phase 110 .", "In that phase, the coordinator 20 analyzes and administers the auction results, which are viewed by the purchaser 10 .", "The purchaser 10 begins to qualify the low bidding supplier 30 or suppliers 30 .", "The purchaser 10 generally retains the right not to award business to a low bidding supplier 30 based on final qualification results or other business concerns.", "[0025] In the ensuing Contract Administration phase 112 , the coordinator 20 facilitates settlements 60 awarded by the purchaser 10 to suppliers 30 .", "Contracts 62 are then drawn up between the purchaser 10 and suppliers 30 .", "[0026] The auction 56 is conducted electronically between potential suppliers 30 at their respective remote sites and the coordinator 20 at its site.", "As shown in FIG. 3, information is conveyed between the coordinator 20 and the suppliers 30 via a communications medium such as a network service provider 40 accessed by the participants through, for example, dial-up telephone connections using modems, or direct network connections.", "A computer system may be used to manage the auction 56 .", "The computer system may have two components: a client component and a server component.", "The client component may operate on a computer at the site of each potential supplier 30 or may be accessed via a supplier computer.", "The client component is used by suppliers 30 to make bids during the auction 56 .", "The bids are sent via the network service provider 40 to the site of the coordinator 20 , where they are received by the server component of the software application.", "[0027] The purchaser 10 may access the auction 56 through the auction coordinator 20 as illustrated in FIG. 3, or may alternately access the auction 56 through a network service provider 40 .", "[0028] In auctions 56 , and in particular reverse auctions, it is desirable that bidder/suppliers 30 actively participate in the auction 56 by submitting lower bids on a regular basis throughout the duration of the auction 56 .", "It is expected that each bidder 30 will consider factors including bids of the other bidders 30 , their own costs, and potential efficiencies that may be had that will reduce the cost to the bidder 30 such that the bidder 30 may submit a reduced bid to the purchaser 10 .", "In certain auctions 56 , however, it has been discovered that certain bidders 30 hold back their bids until late in the time allotted for the auction 56 .", "Other bidders 30 choose not to bid at all during the auction 56 .", "A decision not to bid during an auction 56 may be made for many reasons.", "One reason for not bidding occurs when the bidder 30 is not desirous of being awarded a contract in the auction 56 , but rather is gathering information, such as, for example, the price at which suppliers 30 are willing to provide goods and services.", "When bidders 30 hold their bids until late in the auction 56 or do not bid at all, the benefit of competitive bidding to the purchaser 10 is lost or reduced.", "Furthermore, purchasers 10 and bidders 30 alike may prefer to avoid providing such information to non-participants to protect the confidentiality of the auction 56 .", "[0029] Thus, there is a need for a system and process whereby bidders 30 are encouraged to place a bid 58 .", "There is a further need for a system and process whereby bidders 30 are provided with an incentive to actively participate in an auction 56 by submitting additional, progressively lower bids 58 throughout the auction 56 .", "There is also a need for a system and method of bidding that protects bidding confidentiality.", "SUMMARY OF THE INVENTION [0030] In accordance with a particularly preferred form of the present invention, there is provided a method and system for conducting an auction having at least two competing bidders is disclosed.", "The method includes receiving bid data from at least one bidder and providing the bid data to each bidder that meets a condition for receiving the bid data.", "[0031] An apparatus for determining a suggested bid value that surpasses a selected bid is also disclosed.", "The apparatus includes a computer readable medium having stored thereon instructions which, when executed by a processor, cause the processor to provide a user selectable facility which, when selected establishes the value of the selected bid, calculates the suggested bid value by subtracting a predetermined minimum differential value from the selected bid value, and conveys the suggested bid value to the user.", "[0032] Thus, the present invention provides a method, apparatus and system that beneficially encourages bidders to place a bid.", "[0033] The present invention also provides a method, apparatus and system that beneficially provides bidders with an incentive to actively participate in an auction by submitting additional, progressively lower bids throughout the auction.", "[0034] In addition, the present invention also provides a method, apparatus and system that beneficially protects bidding confidentiality.", "[0035] Accordingly, the present invention provides solutions to the shortcomings of prior online auctions.", "Those of ordinary skill in the art will readily appreciate, therefore, that those and other details, features, and advantages will become further apparent in the following detailed description of the preferred embodiments.", "BRIEF DESCRIPTION OF THE DRAWINGS [0036] The accompanying drawings, wherein like reference numerals are employed to designate like parts or steps, are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, and illustrate embodiments of the invention that together with the description serve to explain the principles of the invention.", "[0037] In the drawings: [0038] [0038 ]FIG. 1 is a schematic illustration of the elements and entities involved in an embodiment of an auction;", "[0039] [0039 ]FIG. 2 is a tabular illustration of the tasks performed by the entities involved in the auction of FIG. 1;", "[0040] [0040 ]FIG. 3 is a schematic illustration of the communications links between the coordinator, the buyer, and the suppliers in the auction of FIG. 1;", "[0041] [0041 ]FIG. 4 is a schematic diagram of an auction network;", "[0042] [0042 ]FIG. 5 is a flow diagram illustrating an information flow of the present invention;", "[0043] [0043 ]FIG. 6 is a sample purchaser screen display that may be used to practice an embodiment of the invention;", "[0044] [0044 ]FIG. 7 is a sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 6;", "[0045] [0045 ]FIG. 8 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 6;", "[0046] [0046 ]FIG. 9 is a flow diagram illustrating another information flow of the present invention;", "[0047] [0047 ]FIG. 10 is a flow diagram illustrating yet another information flow of the present invention;", "[0048] [0048 ]FIG. 11 is a sample purchaser screen display that may be used to practice an embodiment of the invention;", "[0049] [0049 ]FIG. 12 is a sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11;", "[0050] [0050 ]FIG. 13 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11;", "[0051] [0051 ]FIG. 14 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11;", "[0052] [0052 ]FIG. 15 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11;", "and [0053] [0053 ]FIG. 16 is another sample bidder screen display that may be used to practice the embodiment of the invention of FIG. 11.", "DETAILED DESCRIPTION [0054] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.", "It is to be understood that the Figures and descriptions of the present invention included herein illustrate and describe elements that are of particular relevance to the present invention, while eliminating, for purposes of clarity, other elements found in typical auction systems and computer networks.", "The present invention described below extends the operation of the inventive auction systems and methods described in greater detail in co-pending application Ser.", "No. 09/252,790, entitled “Method and System for Controlling Closing Times of Electronic Auctions Involving Multiple Lots”", "filed Feb. 19, 1999, and co-pending Application Ser.", "No. 09/282,157, entitled “Method and System for Conducting Electronic Auctions with Transformation Bidding”", "filed Mar. 31, 1999, the disclosures of which are hereby expressly incorporated in the present application.", "[0055] The preferred embodiments described herein utilize an online reverse auction, wherein the present invention is performed by a computer processor, as an example.", "In those examples, suppliers 30 bid to supply goods or services to a purchaser 10 and the purchaser 10 typically purchases the goods or services from the lowest priced qualified bidder 30 .", "It is to be understood, however, that the present invention may be used in other applications.", "The auction 56 would not necessarily have to occur online and the present invention may be performed by other than a computer processor.", "The present invention may also be utilized in connection with auctions other than reverse auctions.", "For example, the present invention may be advantageously utilized with forward auctions, wherein the party offering the highest priced qualified bid, rather than the lowest priced qualified bid, is awarded the goods or services being sold.", "In the case of a forward auction, the leading bid is the highest amount offered and the leading bidder 30 is the purchaser party 10 making that highest offer, while in a reverse auction, the leading bid is the lowest amount offered and the leading bidder 30 is the supplier party 30 making that lowest bid.", "Similarly, placing a “better bid”", "in a reverse auction indicates placing a lower bid, while placing a “better bid”", "in a forward auction indicates placing a higher bid.", "[0056] [0056 ]FIG. 4 is a diagram illustrating an auction network 70 of the present invention for operating an auction.", "The auction network 70 may be divided into three functional sections;", "a client access network 71 , a communications network 73 , and a data processing network 76 .", "The client access network 71 may, for example, include one or more client machines 72 for accessing and communicating with the communications network 73 .", "The communications network 73 may include one or more primary communications servers 74 , secondary communications servers 75 , and directory, login and reporting servers 90 .", "The data processing network 76 may include production servers 77 , training and reporting servers 80 , reporting and training databases 86 , and production databases 84 .", "The production servers 77 and training and reporting servers 80 are referred to collectively herein as bid servers 77 and 80 .", "[0057] The client machines 72 may be, for example, personal computers located at each bidder 30 and purchaser site 10 for accessing the auction 56 .", "The client machines 72 may access the auction 56 by, for example, connecting to a web site operated by the party hosting the auction 56 .", "The client machines 72 may also receive software from the communications network 73 that facilitates communications with the communications network 73 .", "[0058] The primary communications servers 74 are utilized to provide information to bids 58 received from the client machines 72 to the bid servers 77 and 80 , and to provide that bid information from the bid servers 77 and 80 to the client machines 72 .", "The primary communications servers 74 may furthermore act as a firewall to prevent direct access to the bid servers 77 and 80 by the client machines.", "The secondary communications servers 75 act as backups to the primary communications servers 74 .", "The secondary communications servers 75 will perform the communication functions normally performed by the primary communications servers 74 if a failure occurs in the primary communications servers 74 , thereby providing redundancy to the auction network 70 .", "[0059] The directory, login, and reporting servers 90 may perform a variety of functions that may be performed by a single server or include separate servers for the various functions.", "The directory, login, and reporting servers 90 may include a web server that acts as a portal for access to the auction network 70 .", "As such, the directory, login, and reporting servers 90 will receive login requests for access to the auction network 70 via, for example, the Internet.", "The directory, login, and reporting servers 90 may make access decisions as to whether a client machine 72 is permitted to access the communications network 73 .", "If access is permitted, the directory, login, and reporting servers 90 will direct the client machine 72 to the appropriate portion of the auction network 70 .", "The directory, login, and reporting servers 90 , may provide reports to client machines 72 .", "For example, information from prior auctions 56 which may be utilized by purchasers 10 to make a decision as to which bidder 30 will be awarded the sale and to permit the purchaser 10 to consider the way in which the auction 56 proceeded so that future auctions 56 may be refined.", "[0060] The production servers 77 run the bidding software that facilitates auctions 56 as they occur.", "The production servers 77 may communicate with client machines 72 through primary and secondary communications servers 74 and 75 .", "The production servers 77 may also be redundant so that if a failure occurs in the production server 77 that is being utilized in an auction event 56 , the redundant backup production server 77 may perform the functions of the failed production server 77 and, thus, prevent failure of the auction 56 .", "[0061] The training and reporting servers 80 operate in a manner similar to the production servers 77 and provide reports for auctions 56 .", "It is useful to operate test auctions 56 to test the operating systems and to train personnel and clients.", "Such testing may be performed on the production servers 77 or, to prevent any degradation of system operation in actual auctions 56 , one or more separate training servers may be utilized for testing and training.", "Reporting may also be accomplished on the production servers 77 or the report creation functions may be offloaded to one or more reporting servers 80 .", "The reporting servers 80 may furthermore be combined with the training servers 80 .", "[0062] Data related to auctions 56 may be held in one or more storage devices.", "The data storage devices may, for example, be a magnetic storage device, a random access memory device (RAM), or a read only memory device (ROM).", "The data may include pre-auction data, post auction data, and data that is related to active auctions 56 .", "Pre-auction data may include, for example, suppliers 30 that are permitted to bid on a particular auction 56 and the scheduled auction starting and ending times.", "Post auction data may include the bids and bid times received in a particular auction 56 and reports displaying that data in user friendly formats.", "Active auction data may include data received from the bidders 30 as the auction 56 is taking place and related data such as the rank of each bidder 30 .", "[0063] The “rank”", "of the bidders 30 is determined by comparing the lowest amount bid by each bidder 30 and ordering the bidders 30 according to those lowest bids.", "The bidder ranked first is the bidder 30 that has bid an amount lower than any other bidder 30 in a reverse auction.", "The last rank may be a rank equal to the number of bidders 30 who have submitted bids in the auction 56 , and the bidder 30 having that last rank is the bidder 30 that has submitted the highest amount in a reverse auction that is based on price only.", "Of course, there are many known ways to calculate rank, and any of those may be used in connection with the subject invention.", "The other bidders 30 are ranked between first and last according to the amounts of their lowest submitted bids.", "Thus, a higher, or better ranked bidder 30 in a reverse auction is a bidder 30 who has placed a comparatively lower bid, while a higher, or better ranked bidder 30 in a forward auction is a bidder 30 who has placed a comparatively higher bid.", "An auction 56 may alternately be based on one or more factors other than price, such as quality, delivery factors, and/or other factors that are referred to herein collectively as “total value.”", "Thus, rank may also be based on factors other than price, including total value and any other factor that is useful in an auction 56 setting.", "A bid or bid amount is a value that is submitted by each participating bidder 30 for comparison to the bids of other bidders 30 , and may likewise be based on a variety of bid factors that are considered important to the bid participants.", "Those factors may include, for example, price, quality, other costs such as delivery costs, or a total value.", "Bids may also be placed in a number of ways including, for example, absolute total value, or comparative value such as bidding in relation to an index price.", "[0064] Three databases, or groupings of databases, are incorporated into the auction network illustrated in FIG. 4. The production databases 84 hold data that will be used by or is received from the production servers 77 , while the reporting and training databases 86 hold data that will be used by or is received from the training and reporting servers 80 .", "[0065] The directory, login, and reporting servers 90 illustrated provide a web portal for the client machines 72 .", "The directory, login, and reporting servers 90 provide an initial contact point for the client machines 72 , access to auctions 56 in which the client machine 72 is permitted to participate, and reports relating to active and closed auctions 56 .", "[0066] One skilled in the art will recognize that certain components of the network described herein, while beneficial to an auction network, are not necessary components in an operational auction network.", "For example, the secondary communications servers 75 could be removed where the benefit of redundancy is not desired, and the primary communications servers 74 could be removed and the client machines 72 could communicate directly with the bid servers 77 and 80 .", "[0067] In a business-to-business online auction 56 , bidders 30 may compete openly using their identities, or anonymously wherein bidders 30 view bids 58 placed by other bidders 30 but do not know the identity of those other bidders 30 .", "Feedback about bidding activity is referred to as “market feedback”", "and includes any information or data related to the bidders 30 or their bids or interrelationships between those bids, and any other bid related information or data such as, for example, the quality of goods being sold, that is received before or during the auction 56 .", "Market feedback may include, for example, bids that have been placed by other bidders 30 , the rank of a participants bid in relation to the other bidders 30 , the identity of bidders 30 in relation to their bids or rank, or any subset of that information.", "Market feedback may also include non-pricing information such as, for example, the quality of the goods to be provided by bidders 30 and shipping costs associated with one or more bidders 30 .", "Providing such market feedback to bidders 30 in an auction 56 helps create real-time competitive interaction among participants in the auction 56 because, without feedback, bidders 30 would have less incentive to revise their price quotes and place additional bids to remain competitive.", "[0068] In a certain type of online auction 56 , which may be referred to as “full market feedback format,” all bids 58 are visible to every bidder 30 .", "Bids 58 are sorted from highest to lowest.", "Thus, each bidder 30 can assess its rank and competitive position if bidders 30 are individually identified, by comparing its current best bid 58 with other bids 58 placed in the online auction 56 .", "[0069] In a second type of online auction 56 , bidders 30 are provided with only their own current best bid 58 and the current market-leading bid.", "Bidders 30 are not aware of every bid 58 placed by other participants, but they can assess their competitive position against the current market-leading bid.", "In one variation of that second type of online auction 56 .", "bidders 30 also receive feedback about their current rank.", "[0070] Table 1 illustrates an example of a series of bids 58 placed by different bidders 30 participating in an online reverse auction 56 .", "Each row includes information related to a single bid 58 and the rows are ordered from highest bid to lowest bid.", "In the example illustrated in Table 1, each bidder 30 is identified anonymously.", "The first column lists a bidder identifier that is used in connection with all bids submitted by a particular bidder 30 .", "The second column lists the time the associated bid 58 was received and the third column lists the amount of bid 58 .", "The fourth column indicates the dollar value difference between the bid 58 and the lowest current bid 58 (“market-leading bid”) and the fifth column lists the percentage difference between the bid and the lowest current bid 58 .", "The sixth column indicates the current rank of each bidder 30 next to the best bid 58 submitted by each bidder 30 .", "Table 1 illustrates all of the bids 58 placed by every bidder 30 .", "TABLE 1 A. All bids Bids vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $128,000 23.62% Bidder B 1:01:23 PM $664,000 $122,000 22.51% Bidder C 1:01:28 PM $560,000 $18,000 3.32% Bidder B 1:03:10 PM $559,000 $17,000 3.14% Bidder D 1:02:50 PM $558,500 $16,500 3.04% 7 Bidder A 1:03:38 PM $558,300 $16,300 3.01% 6 Bidder E 1:05:12 PM $557,700 $15,700 2.90% 5 Bidder F 1:05:43 PM $557,500 $15,500 2.86% Bidder C 1:06:49 PM $552,000 $10,000 1.85% Bidder G 1:06:55 PM $549,000 $7,000 1.29% Bidder C 1:07:22 PM $546,800 $4,800 0.89% Bidder F 1:07:49 PM $546,400 $4,400 0.81% 4 Bidder C 1:08:02 PM $546,250 $4,250 0.78% 3 Bidder B 1:08:17 PM $545,000 $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000 $0 0.00% 1 [0071] Applying the full market feedback format to the example illustrated in Table 1, each bidder 30 sees all of the information contained in Table 1 and is thus able to determine its rank and the difference between its best bid and the market-leading bid.", "For example, at 1:08:44 PM Bidder B can see that it is in second place, $3,000 above the market-leading bid placed by Bidder, G. Bidder F can see that it is in fourth place, $4,400 above the market-leading bid placed by Bidder G, $1,400 above Bidder B in second place, and $150 above Bidder C in third place.", "[0072] Each bidder 30 also receives market feedback regarding all bids 58 placed up to that time throughout the auction 56 if the full market feedback format is utilized.", "Thus, at 1:04:00 PM, the market-leading bid 58 is held by Bidder A, who placed a bid of $558,300 at 1:03:38 PM.", "That bid, and all other bids placed prior to that time are visible to all bidders, including Bidder E, who at that point in the auction 56 has not placed a bid 58 .", "By viewing the current market activity, Bidder E is able to formulate an appropriate first bid and submit a new market-leading, bid of $557,500 at 1:05:12 PM.", "[0073] The full market feedback format is particularly effective for many industrial commodities and supply markets but may be utilized in any type auction 56 .", "However, in certain auctions 56 , particularly those conducted in industrial and business-to-business settings, that form of market feedback generates sub-optimal results or unwanted side-effects that damage the integrity of the process.", "For example, in certain auctions 56 , the sponsor, which in the case of a reverse auction is typically the purchaser 10 , may not want pricing information to be disclosed to a large number of parties to minimize the likelihood that the pricing information will be released to the public.", "A sponsor may also wish to conceal the number of bidders that are available or participating in the auction 56 .", "In other auctions 56 , disingenuous participants will watch the auction 56 without bidding.", "Qualified bidders 30 that claim to be interested in bidding may view the entire auction 56 without ever submitting a bid.", "Such participants learn market pricing, information, and auction results that may have value for general business purposes beyond the scope of the particular supply opportunity up for bid.", "For many business-to-business auctions 56 , this is not a serious issue.", "For example, where the format of the auction 56 is such that bids are for aggregate “lots”", "of business consisting of many line items with individual unit prices, bidders 30 may compete at the lot level so that they see only aggregate or lot-level bids placed by other bidders 30 rather than the cost of each separate item being purchased.", "That severely limits the value of the pricing information certain bidders 30 are able to gather from watching the auction 56 because there is no way to deduce unit prices for separate items with any real accuracy.", "In certain other auctions 56 , the items for bid are custom-engineered components or inputs specific to a particular purchaser 10 such that the pricing information is not readily transferable or useful in other business contexts.", "[0074] For some auctions 56 , however, especially where the bidding format reveals unit pricing or the product is, for example, a commodity or standard item purchased by multiple purchasers 10 , allowing visibility to market pricing is a more sensitive issue for the genuine participants.", "In those cases, genuine bidders 30 may be discouraged from submitting the lowest price quotes they are prepared to offer due to fear that disingenuous competitors may be viewing the auction 56 and may use information learned from the auction 56 against the genuine bidders 30 in the marketplace beyond the particular supply opportunity up for bid.", "In extreme cases, that fear may be sufficient to discourage certain bidders 30 from participating in the auction 56 .", "For example, when a bidder 30 determines that the potential loss of the supply opportunity provided by the auction 56 is less damaging than the risk of damage that could occur to the entire base of business of the supplier 30 from revealing pricing information, the bidder 30 may opt not to participate in an auction 56 or not to price as aggressively in an auction 56 as the bidder 30 might otherwise.", "To guarantee full and aggressive participation, it is beneficial to assure bidders 30 that no bidders 30 are watching the auction 56 without actively participating themselves.", "[0075] In certain other auctions 56 , genuine participants may exploit market pricing learned from the auction 56 .", "There are circumstances where the supply industry dynamic is such that, even when all bidders 30 intend to participate, some bidders 30 will fail to participate, or will offer less aggressive quotes than they otherwise would, for fear that they will reveal critical pricing information that will “leak”", "into the marketplace and damage their businesses.", "For example, a losing bidder 30 may learn the identity of the successful bidder 30 in a particular auction 56 through industry gossip.", "In a subsequent competitive selling situation that losing bidder 30 may inform another purchaser 10 of the pricing that the successful bidder 30 quoted in the previous auction 56 .", "Thus, the winning bidder 30 is placed in an awkward position with subsequent purchasers 10 who may suspect that the successful bidder 30 had been supplying them with goods at a price higher than the bidder 30 was prepared to offer other customers.", "That situation may occur, for example, where (i) the bid format is structured to permit visibility to easily comparable pricing information (e.g., unit pricing);", "(ii) the commodity is a standard material purchased by multiple purchasers 10 (e.g., an industry standard grade of a particular chemical, such as 99% USP Food Grade Glycerin);", "and (iii) the industry structure is a consolidated “tight-knit”", "community where bidders 30 may learn the identity of the successful bidders 30 through market intelligence subsequent to the auction 56 .", "[0076] Another market feedback problem occurs in cases where bidders 30 , such as preferred suppliers 30 or “incumbent suppliers”", "(i.e., bidders 30 that are current or past suppliers 30 to the purchaser 10 ) bid significantly behind the market leading bid.", "In an auction 56 for an industrial component or input, for example, purchasers 10 may reserve the right to award to a non-low-bidding supplier 30 .", "That allows purchasers 10 to consider non-price factors, such as relationship history, service considerations, and location, that are material to establishing a supply contract with a particular bidder 30 .", "While the lowest bidder 30 generally enjoys a favored position with respect to receiving the award, the purchaser 10 may be prepared to trade-off a higher price for other benefits.", "Similarly, preferred suppliers 30 may believe that they can offer significant non-price benefits beyond the specified requirements, and may choose to bid at a premium to the market-leading bid.", "While that may not be an illogical bidding strategy or undesirable market dynamic, in certain situations suppliers 30 may over-estimate the premium the purchaser 10 is willing to pay for perceived non-price benefits.", "That may lead preferred suppliers 30 to offer significantly less aggressive price quotes than they otherwise would if they realized how little value the purchaser 10 truly places on the non-price benefits.", "Thus, a preferred supplier 30 may not realize its tactical en-or until the purchaser 10 awards the business to a more competitive supplier 30 .", "At that point, the auction 56 has closed and it is too late for the preferred supplier 30 to revise its bid to a lower value.", "The preferred supplier 30 will have, therefore, lost an opportunity to make a sale, and the purchaser 10 will also have lost the potential to award the sale to the preferred supplier 30 at a price within the expectation of the purchaser 10 .", "[0077] Another problem related to bidding behind the market occurs where incumbent suppliers 30 exploit market feedback to avoid competition.", "That problem may arise when a purchaser 10 selects a pricing structure, for example a fixed price or a differential price, that a non-incumbent supplier 30 must match or beat to be selected over an incumbent supplier 30 .", "In such a case, for example, an incumbent supplier 30 could know that the purchaser 10 favors the incumbent supplier 30 even at a price premium to the market.", "Because the purchaser 10 may pass over low bidders 30 , incumbent suppliers 30 can take advantage of their incumbent status.", "To ameliorate that disadvantage for new suppliers 30 , it is common to communicate a “reserve price”", "to all bidders 30 prior to the auction 56 .", "The reserve price represents the price at which the purchaser 10 will be willing to switch the business from the incumbent to a new source.", "Reserve price may be calculated in various ways including deducting the switching costs of the purchaser 10 from the “historic price”", "that the incumbent is currently charging the purchaser 10 .", "The use of such a reserve price affords new suppliers 30 an opportunity to offset the incumbent's advantage by ensuring that their bids are low enough for the purchaser 10 to recover any switching costs that Would otherwise prevent them from receiving the award.", "[0078] In certain embodiments, the reserve price may be permitted to fluctuate when an incumbent bids an amount lower than the historic price.", "In such a situation, when an incumbent lowers its bid to less than the historic price, then the effective price required for a purchaser 10 to switch to a new supplier 30 will be lower than a reserve price that was a fixed amount below the historic price.", "Since an incumbent may calculate the differential between reserve and historic prices when the reserve price fluctuates, and can view the low bid, the incumbent can exploit its position by bidding behind the market by an amount slightly less than the differential between the historic and reserve prices.", "While being a reasonable rationale for the incumbent, that situation does not allow the purchaser 10 to maximize the competitive dynamic between incumbent and potential new suppliers 30 .", "In addition, new suppliers 30 often perceive this situation to be unfair because they are unable to identify an incumbent when bidding is anonymous.", "[0079] It may thus be beneficial to reward more aggressive bidders 30 with more information about bidding activity in certain circumstances (i.e., the closer a bidder's 30 current bid is to the market-leading bid, the more information about other bids placed in the market is provided to that bidder 30 ).", "The present invention includes improved online auction technology that allows market feedback to be made visible to each bidder 30 according to that bidder's level 30 of participation and relative position in the market (“differential market feedback”).", "[0080] “Differential market feedback technology”", "includes a variety of feedback mechanisms that may be used to differentiate bidders 30 while “differential market feedback rules”", "are used to define when a bidder 30 can view market feedback and may use differential market feedback technology in that determination.", "An example of differential market feedback technology as it is used to measure the market position of each bidder 30 relative to all other bidders 30 involves comparing the highest bid of each bidder 30 to the current market-leading bid.", "Examples of differential market feedback technology as it is used to measure market position relative to fixed reference points include ranking each bidder 30 , calculating the percentage differential between the bids of two or more bidders 30 , and calculating the absolute differential between the bids of two or more bidders 30 .", "Market position may also be determined relative to a fixed reference point by comparing each bid to a reserve price selected by the purchaser 10 or a historic price paid by the purchaser 10 in the past.", "[0081] Differential market feedback rules may include consideration of factors including level of market participation and market position.", "Market participation can be measured, for example, by whether the bidder 30 has submitted a bid at all, or by whether the bidder 30 has submitted a bid within a pre-determined time period between current time and the last time a bid was placed by that bidder 30 .", "Market position can be measured, for example, relative to other bids in the auction 56 or relative to a fixed reference point.", "Other known methods of measuring market participation and market position are known to those skilled in the art and are intended to be encompassed by the present invention.", "[0082] Differential market feedback rules may also take into consideration the relative positioning of bidders 30 as determined by the differential market feedback technology.", "Depending on the participation and position of a bidder 30 , the bidder 30 may, for example, be provided no feedback as to the market, the rank of the bidder 30 , information regarding only bids that are greater than (worse than) the lowest bid of that bidder 30 , information regarding the next lowest bid to the best bid placed by the bidder 30 , information regarding the market-leading bid, or information regarding all bids placed.", "[0083] By combining feedback rules and feedback types, an auction 56 may utilize a differential market feedback format uniquely suited to the requirements of each auction 56 , wherein the differential market feedback technology dynamically adjusts the feedback visible to each bidder 30 depending on their position in the auction 56 and other factors.", "[0084] [0084 ]FIG. 5 is a flow diagram 120 illustrating an embodiment of the present invention wherein access to market feedback is restricted to those bidders 30 who have submitted at least one valid bid.", "This example, and other examples provided herein, assume that a computer processor is executing a set of instructions that perform the steps, however, it will be recognized by one skilled in the art that the instructions may be carried out by any known method.", "At 122 of the embodiment illustrated in FIG. 5, the auction 56 is commenced by accepting bids from the bidders 30 .", "The auction 56 normally begins at a scheduled time that has been prearranged by the auction coordinator 20 , the purchaser 10 and the bidders 30 .", "At 124 a bid is received from any bidder 30 participating in the auction 56 .", "That bid, as well as any other bid discussed herein, may be a bid that is created by a bidder 30 and submitted to the data processing network 77 from the client machine 72 by way of the communication network 53 .", "At 126 the processor determines which bidders 30 have submitted at least one bid and, for example, sets a flag identifying those bidders 30 as “bid participants”", "[0085] At 128 through 144 , an example is provided of the bid participant segment of this embodiment, wherein market feedback is provided only to those bidders 30 who have placed at least one bid and are, thus, bid participants.", "In that example, “n”", "represents the number of bidders 30 that are permitted by the auction coordinator 20 to participate in the auction 56 .", "At 128 , the processor checks to see whether Bidder one is a bid participant.", "At 130 , market feedback is provided to Bidder one if Bidder one is a bid participant and at 132 , market feedback is withheld from Bidder one if Bidder one is not a bid participant.", "[0086] Similarly, at 134 , the processor checks to see whether Bidder two is a bid participant.", "At 136 , market feedback is provided to Bidder two if Bidder two is a bid participant and at 138 , market feedback is withheld from Bidder two if Bidder two is not a bid participant.", "The processor will continue by considering the bid participant status of each bidder 30 and provide market feedback to only those bidders 30 who are bid participants.", "At 140 , the processor checks to see whether the last bidder 30 (Bidder n) is a bid participant.", "At 142 , market feedback is provided to Bidder n if Bidder n is a bid participant and at 144 , market feedback is withheld from Bidder n if Bidder n is not a bid participant.", "[0087] After the bid participant segment has been completed, the processor will determine whether the auction closing time has arrived at 146 .", "If the auction closing time has not arrived, the processor will return to 124 to receive additional bids.", "Each time a new bid is received the processor will update the bid participant status of the bidders 30 and provide market feedback to all bid participants.", "If the auction closing time has arrived, the auction 56 will close and no additional bids will be accepted.", "[0088] Additional conditions may be placed on a bidder 30 prior to permitting the bidder 30 to access market feedback.", "As an example of one condition, any bidder 30 that places a noncompetitive bid, (i.e., a bid in excess of a predetermined amount in a reverse auction) is not permitted to view market feedback until that bidder 30 places a competitive bid.", "Such a competitive bid may include a bid that is less than a predetermined amount in a reverse auction and a bid that is greater than a predetermined amount in a forward auction.", "Alternately or in addition, a bidder 30 who is receiving market feedback may stop receiving market feedback if an extended period of time has elapsed since that bidder 30 placed its last bid, or if the bid is determined to be invalid.", "Another method of assuring that each bidder 30 places at least one competitive bid, is to require each bidder to submit and commit to such a competitive bid prior to commencement of the auction 56 .", "The auction 56 may then begin by having the auction coordinator 20 enter those bids into the auction network 70 .", "[0089] FIGS. 6 - 8 illustrate sample screens that may be displayed for various participants in a particular auction 56 utilizing the rule that access to market feedback is restricted to those bidders 30 who have submitted at least one bid.", "FIG. 6 illustrates a sample of a screen 150 that may be displayed to the purchaser 10 .", "A lot listing 152 includes statistics related to three lots of parts that are being auctioned.", "Lot three is highlighted in the lot listing 152 , indicating that lot three is active in the rest of the screen 150 .", "At 154 , statistics for all three lots are displayed and at 156 additional statistics for lot three are displayed.", "A bid history 158 , listing bids received for lot three, is also provided because lot three is the active lot.", "The lot three bid history 158 is arranged from the highest bid amount to the lowest amount bid.", "[0090] [0090 ]FIG. 7 illustrates a sample of a screen 160 that may be displayed to a bidder 30 who has not submitted a valid bid for lot three during the course of the auction 56 .", "At 162 , statistics regarding the market, or bids placed by other bidders 30 , are provided in connection with lots one and two only.", "The bidder 30 is provided with a bid submission area 164 , with which a bid may be formulated and submitted.", "The bidder 30 is also provided with a general status area 166 and a lot specific status area 168 , that includes information related to active lot three.", "It will be noted that the rank and total bids statistics are blank in FIG. 7 because the bidder 30 viewing FIG. 7 has not submitted a bid for lot three.", "At bid history area 170 , the bid history is provided if the bidder 30 viewing screen 160 had placed a valid bid.", "Because the bidder 30 has not placed a bid, however, a message stating “bid history is not available until you submit a valid bid in this lot”", "is displayed in the bid history area 170 .", "[0091] [0091 ]FIG. 8 illustrates a sample of a screen 180 that may be displayed to a bidder 30 who has submitted a valid bid for lot three during the course of the auction 56 .", "At lot listing 182 , statistics regarding the market or bids placed by other bidders 30 are provided in connection with lots one and two and three because the viewing bidder 30 has placed at least one valid bid for each of those lots.", "At bid submission area 184 , the bidder 30 is provided an area from which a bid may be formulated and submitted.", "At 186 , the bidder 30 is provided with a general status area and at 188 a status area for lot three, which is active because it is selected at 162 , is provided.", "It will be noted that the rank and total bids fields are displayed in FIG. 8 because the bidder 30 viewing FIG. 8 has submitted a valid bid for lot three.", "At 190 the bid history, including the amount of every bid placed and identifier for each bidder 30 is provided.", "EXAMPLE 1 [0092] The embodiment of the invention depicted in FIGS. 5 - 8 may also be illustrated by reference to Tables 1 through 5.", "In that embodiment, market feedback is provided to only those participants who have placed a valid bid.", "That prevents disingenuous participants from watching the auction 56 to gather pricing intelligence without placing a bid themselves and forces participants to take some risk by submitting a bid before they are able to view market feedback.", "That embodiment also discourages bidders 30 from waiting until the last moment to place a bid because no competitive information regarding the bid is available to a bidder 30 until that bidder 30 submits its first bid.", "[0093] Referring to the bidding activity shown in Table 1, at 1:04:00 PM, Bidders A, B, C, and D have submitted bids into the auction 56 , while Bidders E, F and G have not.", "Accordingly, in the current embodiment, market feedback would only be made available to Bidders A, B, C, and D at 1:04:00 PM, and those bidders 30 would view all bids placed by all bidders 30 at that time.", "Thus, the information provided to Bidders A, B, C, and D at 1:04:00 PM would appear as shown in Table 2.", "TABLE 2 1.", "Market Participants Only Bids vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14% Bidder B 1:01:23 PM $664,000 $106,300 19.06% Bidder C 1:01:28 PM $560,000 $2,300 0.41% 4 Bidder B 1:03:10 PM $559,000 $1,300 0.23% 3 Bidder D 1:02:50 PM $558,500 $800 0.14% 2 Bidder A 1:03:38 PM $558,300 $600 0.11% 1 [0094] Bidders E, F and G would not receive any market feedback at 1:04:00 PM.", "Thus, the information provided to Bidders E, F, and G at 1:04:00 PM would appear as shown in Table 3.", "TABLE 3 1.", "Market Participants Only Bids vs.", "Market Lead Bid Time Bid $ % Rank [0095] Again referring to Table 1, at 1:05:12 PM, Bidder E placed a bid of $557,700.", "As soon as that bid is submitted, Bidder E receives full feedback of all bids placed in the market.", "In this instance, Bidder E has placed a new market-leading bid, although this is not apparent to Bidder E until after the bid has been submitted.", "Thus, Bidder E and Bidders A, B, C, and D would see the bid history shown in Table 4 after the 1:05:12 PM bid has been submitted and Bidder E would realize lie has submitted the market-leading bid.", "TABLE 4 1.", "Market Participants Only Bids vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14% Bidder B 1:01:23 PM $664,000 $106,300 19.06% Bidder C 1:01:28 PM $560,000 $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000 $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500 $800 0.14% 3 Bidder A 1:03:38 PM $558,300 $600 0.11% 2 Bidder E 1:05:12 PM $557,700 $— 0.00% 1 [0096] In this embodiment, once a bidder 30 has placed a bid, that bidder 30 is entitled to continue to see all bid history for the remainder of the auction 56 regardless of whether they submit any additional bids.", "Hence, at the end of the auction 56 at 1:09:00 PM, Bidder E will view the bid history shown below in Table 5, even though Bidder E had not place any additional bids.", "TABLE 5 1.", "Market Participants Only Bids vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $128,000 23.62% Bidder B 1:01:23 PM $664,000 $122,000 22.51% Bidder C 1:01:28 PM $560,000 $18,000 3.32% Bidder B 1:03:10 PM $559,000 $17,000 3.14% Bidder D 1:02:50 PM $558,500 $16,500 3.04% 7 Bidder A 1:03:38 PM $558,300 $16,300 3.01% 6 Bidder E 1:05:12 PM $557,700 $15,700 2.90% 5 Bidder F 1:05:43 PM $557,500 $15,500 2.86% Bidder C 1:06:49 PM $552,000 $10,000 1.85% Bidder G 1:06:55 PM $549,000 $7,000 1.29% Bidder C 1:07:22 PM $546,800 $4,800 0.89% Bidder F 1:07:49 PM $546,400 $4,400 0.81% 4 Bidder C 1:08:02 PM $546,250 $4,250 0.78% 3 Bidder B 1:03:17 PM $545,000 $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000 $— 0.00% 1 [0097] It should be noted that in example one and the following examples, the term “rank”", "indicates rank of bidders.", "Alternately, rank may be based on bids such that the bid placed by Bidder C at 1:07:22 PM in Table 5 would be ranked fifth.", "EXAMPLE 2 [0098] In another embodiment, a bidder 30 will not view any market feedback unless the current best bid of that bidder 30 is within a group of “market leaders.”", "Whether a bid qualifies the submitting bidder 30 as a market leader may be determined in many ways including, for example, a bidder 30 may be a market leader when that bidder 30 places a bid that is within no more than a predetermined percentage behind the market-leading bid.", "For example, the bidder 30 may be provided with market feedback as long as the lowest bid of that bidder 30 is no more than 2% behind the market-leading bid.", "Alternately, a bid may be considered a market leader if the lowest bid of that bidder 30 ranks no more than a specified number of places behind the market-leading bid.", "For example, the bidder 30 may be provided with market feedback as long as the lowest bid of that bidder 30 is one of the top three bids.", "In yet another alternative, a bid may be considered a market leader if the lowest bid of that bidder 30 is within no more than a predetermined absolute value behind the market-leading bid;", "for example, no more than $10,000 behind the market-leading bid.", "[0099] In the market leader embodiments, bidders 30 may view market feedback only as long as their bid remains within the market-leading group of bids.", "The first time a bidder 30 submits a bid within the market-leading group, they will be able to view market feedback.", "Up until that point (or if a bidder 30 does not submit a bid at all), no market feedback will be provided to that bidder 30 .", "If, in the course of the auction 56 , a bidder 30 falls out of the market-leading group because other bidders 30 have exceeded the rank of bidder 30 , the market feedback may not be updated for that bidder 30 from the point in time at which that bidder 30 fell out of the market-leading group.", "That is, the market feedback will freeze at that point and will not be updated until that bidder 30 regains a market-leading position.", "In this example, if the bidder 30 places another bid and regains a market-leading position, the market feedback for that bidder 30 will be updated to include all bids placed to that point in time, including the bids placed while the bidder 30 was out of the market-leading group.", "Hence, a bidder 30 might gain, lose, and re-gain visibility to market feedback many times during the course of an auction 56 depending on the competitive interaction between all of the bidders 30 .", "[0100] The market leader format rewards the most aggressive bidders 30 with the most pricing information from the auction 56 and prevents non-participating or uncompetitive bidders 30 from learning pricing information.", "It limits the disclosure of final auction results to all but the most aggressive bidders 30 , decreasing the risk to the market leaders that valuable pricing information will “leak out”", "to a broader marketplace.", "The decision about how to define the market-leading group can be used by the auction coordinator 20 as a strategic signal to all bidders 30 about the intentions of the purchaser 10 with respect to awarding the business.", "E.g., defining market leaders as the top three bidders 30 might be used as a signal that the award will go to one of the top three bidders 30 .", "That might, in turn, drive more aggressive bidding by all bidders 30 .", "Even incumbents are encouraged to stay in the top three ranked bidders 30 to avoid the risk of being so far behind the leaders that the purchaser 10 can comfortably justify the switching costs of moving the business.", "[0101] [0101 ]FIG. 9 is a flow diagram 200 illustrating an embodiment of the present invention wherein access to market feedback is restricted to those bidders 30 who are market leaders.", "At 202 of the embodiment illustrated in FIG. 9, the auction 56 commences by accepting bids from the bidders 30 .", "At 204 , a bid is received from any bidder 30 participating in the auction 56 .", "At 206 , the processor determines which bidders 30 are market leaders based on predetermined conditions such as the differential market feedback technology and the differential market feedback rules.", "The processor may then set a flag identifying the market leading bidders 30 as such.", "[0102] At 208 through 224 , an example is provided of the bid participant segment wherein market feedback is provided only to market leading bidders 30 .", "In that example, “n”", "represents the number of bidders 30 that are permitted by the auction coordinator to participate in the auction 56 .", "At 208 , the processor checks to see whether Bidder one is a market leader.", "At 210 , market feedback is provided to Bidder one if Bidder one is a market leader and at 212 , market feedback is withheld from Bidder one if Bidder one is not a market leader.", "[0103] Similarly, at 214 , the processor checks to see whether Bidder two is a market leader.", "At 216 , market feedback is provided to Bidder two if Bidder two is a market leader and at 218 , market feedback is withheld from Bidder two if Bidder two is not a market leader.", "The processor will continue to consider the market leading status of each bidder 30 and provide market feedback to only those bidders 30 who are market leaders.", "At 220 , the processor checks to see whether the last bidder 30 (Bidder n) is a market leader.", "At 222 , market feedback is provided to Bidder n if Bidder n is a market leader and at 144 , market feedback is withheld from Bidder n if Bidder n is not a market leader.", "[0104] After the bid participant segment has been completed, the processor will determine whether the auction closing time has arrived at 226 .", "If the auction closing time has not arrived, the processor will return to 204 to receives any additional bids that have been received.", "Each time a new bid is received the processor will update the market leading status of the bidders 30 and provide market feedback to all market leaders.", "If the auction closing time has arrived, the auction 56 will close and no additional bids will be accepted.", "[0105] Consider again the sequence of bidding activity in Table 1, assuming this time that the market leader format is being used such that bidders 30 must to be within 2% of the market-leading bid to view bidding activity.", "At 1:04:00 PM, Bidder E does not receive any market feedback because Bidder E has not yet placed any bids.", "Thus, the view of the market by Bidder E at 1:04:00 PM, is as shown in Table 6.", "TABLE 6 2.", "Market Leaders Only Bids vs.", "Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted.", "[0106] At 1:05:12 PM, Bidder E places a bid of $557,700, which is a new market-leading bid.", "After that bid has been placed, Bidder E is provided all permitted market feedback Lip until that point including all the bidding activity that had not previously been provided to Bidder E. Bidder E would see the bid history shown in Table 7 after the 1:05:12 PM bid is received.", "TABLE 7 2.", "Market Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14% Bidder B 1:01:23 PM $664,000 $106,300 19.06% Bidder C 1:01:28 PM $560,000 $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000 $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500 $800 0.14% 3 Bidder A 1:03:38 PM $558,300 $600 0.11% 2 Bidder E 1:05:12 PM $557,700 $— 0.00% 1 [0107] Bidder E is in a position to continue to view all bids placed by all bidders 30 unless and until the current best bid of Bidder E falls more than 2% behind the market-leading bid.", "Thus, Table 8 illustrates the market feedback that is provided to Bidder E at 1:07:22 PM because at that time, the best bid of Bidder E is within 2% of the market leading bid.", "TABLE 8 2.", "Market Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $123,200 22.53% Bidder B 1:01:23 PM $664,000 $117,200 21.43% Bidder C 1:01:28 PM $560,000 $13,200 2.41% Bidder B 1:03:10 PM $559,000 $12,200 2.23% 7 Bidder D 1:02:50 PM $558,500 $11,700 2.14% 6 Bidder A 1:03:38 PM $558,300 $11,500 2.10% 5 Bidder E 1:05:12 PM $557,700 $10,900 1.99% 4 Bidder F 1:05:43 PM $557,500 $10,700 1.96% 3 Bidder C 1:06:49 PM $552,000 $5,200 0.95% Bidder G 1:06:55 PM $549,000 $2,200 0.40% 2 Bidder C 1:07:22 PM $546,800 $— 0.00% 1 [0108] In the example illustrated in FIG. 8, Bidders C, F, and G have all bid below the original bid placed by Bidder E. Bidder E has not responded with any additional bids and so now ranks in fourth place, $10,900 behind the current low bid placed by Bidder C. The bid submitted by Bidder E, however, is only 1.99% higher than that of Bidder C who holds the market-leading bid of $546,800 at 1:07:22 PM.", "[0109] However, consider what occurs at 1:07:49 PM when Bidder F places a new market-leading bid of $546,400 into the auction 56 .", "At that point in time, Bidder E's current best bid is $11,300 or 2.07% behind the market-leading bid.", "Because the price differential between Bidder E and the market-leading bid is more than the 2% differential required to stay within the market-leading group of bidders 30 , Bidder E receives one final update of bid history alerting Bidder E to the fact that no further feedback will be made available to Bidder E until Bidder E submits a lower bid within 2% of the current low bid.", "Thus, Table 9 illustrates the market feedback that is provided to Bidder E at 1:07:49 PM because at that time, the best bid of Bidder E is no longer within 2% of the market leading bid.", "TABLE 9 2.", "Market Leaders Only Bidder Bid Time Bid Bidder A 1:02:45 PM $670,000 Bidder B 1:01:23 PM $664,000 Bidder C 1:01:28 PM $560,000 Bidder B 1:03:10 PM $559,000 Bidder D 1:02:50 PM $558,500 Bidder A 1:03:38 PM $558,300 Bidder E 1:05:12 PM $557,700 Bidder F 1:05:43 PM $557,500 Bidder C 1:06:49 PM $552,000 Bidder G 1:06:55 PM $549,000 Bidder C 1:07:22 PM $546,800 [0110] After 1:07:49 PM, Bidder E may only view more bid history if Bidder E places a new lower bid within 2% of the market-leading bid.", "In this example, while the bidding continued until 1:08:44 PM, Bidder E did not re-bid at any time so Bidder E did not receive any further feedback about the market-leading bidding activity in the auction 56 .", "[0111] In the example illustrated in Tables 7-9, Bidder E did not receive updates about rank or the differential (in dollars or percentage) from the market leading bid after 1:07:22 PM.", "That prevents Bidder E from learning any more information about recent market activity.", "Alternative implementations of the format illustrated in Tables 7-9 could allow rank and/or differentials information to be continuously updated depending on the degree to which the auction coordinator 20 wishes to limit disclosure of market leading bidding activity to non-market leaders.", "EXAMPLE 3 [0112] We will now consider how the same auction 56 will be viewed by Bidder E if the market leader format is used such that bidders 30 had to be ranked within the top three in order to view bidding activity.", "Again, as shown in Table 10, at 1:04:00 PM, Bidder E would not receive any market feedback because Bidder E has not placed bid.", "TABLE 10 3.", "Market Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted.", "[0113] At 1:05:12 PM, Bidder E places a bid of $557,700, which is a new market-leading bid such that Bidder E is ranked first.", "Because that rank is at least third, Bidder E is entitled to view all bid history Up until that point.", "Bidder E, therefore, is provided with the history shown in Table 11.", "TABLE 11 3.", "Market Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14% Bidder B 1:01:23 PM $664,000 $106,300 19.06% Bidder C 1:01:28 PM $560,000 $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000 $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500 $800 0.14% 3 Bidder A 1:03:38 PM $558,300 $600 0.11% 2 Bidder E 1:05:12 PM $557,700 $— 0.00% 1 [0114] At 1:05:12 PM, Bidder E is in a position to continue to view all bids placed by all bidders 30 unless and until the current best bid of Bidder E falls into fourth or worse place.", "Bidder E, therefore, sees the market feedback illustrated in Table 12 at 1:06:49 PM.", "TABLE 12 3.", "Market Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $118,000 21.38% Bidder B 1:01:23 PM $664,000 $112,000 20.29% Bidder C 1:01:28 PM $560,000 $8,000 1.45% Bidder B 1:03:10 PM $559,000 $7,000 1.27% 6 Bidder D 1:02:50 PM $558,500 $6,500 1.18% 5 Bidder A 1:03:38 PM $553,300 $6,300 1.14% 4 Bidder E 1:05:12 PM $557,700 $5,700 1.03% 3 Bidder F 1:05:43 PM $557,500 $5,500 1.00% 2 Bidder C 1:06:49 PM $552,000 0.00% 1 [0115] At 1:06:49 PM, Bidders C and F have submitted bids below that of Bidder E. Bidder E has not responded with any additional bids and so now ranks third, $5,700 behind the current low bid placed by Bidder C. Because Bidder E still ranks in the top three bidders 30 , Bidder E is able to continue to view all current market feedback.", "[0116] However, at 1:06:55 PM when Bidder G submits a new market-leading bid of $549,000.", "Bidder E's current best bid is ranked behind three other participants: Bidder G at $549,000, Bidder C at $552,000, and Bidder F at $557,500.", "That places Bidder E in fourth place overall and puts Bidder E outside of the market leaders as defined for this particular auction 56 .", "Bidder E, therefore, receives one final update of bid history alerting Bidder E to the fact that no further feedback will be made available to Bidder E until Bidder E submits a bid low enough to place E within the top three bidders 30 once again.", "The market feedback provided to Bidder E after the 1:06:55 PM bid by Bidder G is shown in Table 13.", "TABLE 13 3.", "Market Leaders Only Bidder Bid Time Bid Bidder A 1:02:45 PM $670,000 Bidder B 1:01:23 PM $664,000 Bidder C 1:01:28 PM $560,000 Bidder B 1:03:10 PM $559,000 Bidder D 1:02:50 PM $558,500 Bidder A 1:03:38 PM $558,300 Bidder E 1:05:12 PM $557,700 Bidder F 1:05:43 PM $557,500 Bidder C 1:06:49 PM $552,000 [0117] After 1:06:49 PM when Bidder E fell to the fourth highest bidder 30 , Bidder E will no longer receive market feedback unless Bidder E places a new lower bid that raises Bidder E to at least the rank of fourth.", "It is noteworthy that compared to the market leader format of the previous example, which was based on a 2% differential, Bidder E lost access to market feedback earlier in the Example 3 of sequence of bidding activity because of the difference in definition of a market leader.", "EXAMPLE 4 [0118] The next example illustrates how the same auction 56 is viewed by Bidder E when the market leader format is used such that bidders 30 must be within $10,000 of the current low bid to view bidding activity.", "Again, at 1:04:00 PM, Bidder E does not receive any market feedback because Bidder E has not placed a bid, as shown in Table 14.", "TABLE 14 4.", "Market Leaders Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted.", "[0119] At 1:05:12 PM, Bidder E places a bid of $557,700, which is a new market-leading bid.", "That entitles Bidder E to view all bid history up until that point.", "Bidder E would, therefore, see the bid history shown in Table 15.", "TABLE 15 4.", "Market Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $112,300 20.14% Bidder B 1:01:23 PM $664,000 $106,300 19.06% Bidder C 1:01:28 PM $560,000 $2,300 0.41% 5 Bidder B 1:03:10 PM $559,000 $1,300 0.23% 4 Bidder D 1:02:50 PM $558,500 $800 0.14% 3 Bidder A 1:03:38 PM $558,300 $600 0.11% 2 Bidder E 1:05:12 PM $557,700 $— 0.00% 1 [0120] Once Bidder E has placed a bid that is within $10,000 of the lowest bid, such as the market leading bid of $557,000 placed at 1:05:12 PM, Bidder E will receive market feedback related to all bids placed by all bidders 30 unless and until the current best bid of Bidder E falls more than $10,000 behind the market-leading bid.", "Thus, the market feedback provided to Bidder E at 1:06:55 PM is shown in Table 16.", "TABLE 16 4.", "Market Leaders Only Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $121,000 22.04% Bidder B 1:01:23 PM $664,000 $115,000 20.95% Bidder C 1:01:28 PM $560,000 $11,000 2.00% Bidder B 1:03:10 PM $559,000 $10,000 1.82% 7 Bidder D 1:02:50 PM $558,500 $9,500 1.73% 6 Bidder A 1:03:38 PM $558,300 $9,300 1.69% 5 Bidder E 1:05:12 PM $557,700 $8,700 1.58% 4 Bidder F 1:05:43 PM $557,500 $8,500 1.55% 3 Bidder C 1:06:49 PM $552,000 $3,000 0.55% 2 Bidder G 1:06:55 PM $549,000 $— 0.00% 1 [0121] At 1:06:55 PM Bidders C, F, and G have all bid below the original bid placed by Bidder E. Bidder E has not responded with any additional bids and so now ranks in fourth place, 1.58% behind the current low bid placed by Bidder G. There is, however, only a differential of $8,700 between Bidder E's current best bid of $557,700 and the market-leading bid of $549,000 submitted by Bidder G. [0122] At 1:07:22 PM, Bidder C places a new market-leading bid of $546,800 into the auction 56 .", "At that point in time, the current best bid of Bidder E is $10,900 or 1.99% behind the market-leading bid.", "$10,900 is more than the $10,000 differential required to stay within the market-leading group of bidders 30 .", "Accordingly, Bidder E receives one final update of bid history alerting Bidder E to the fact that no further feedback will be made available until Bidder E submits a lower bid that is within $10,000 of the current low bid, as is shown in Table 17.", "TABLE 17 4.", "Market Leaders Only Bidder Bid Time Bid Bidder A 1:02:45 PM $670,000 Bidder B 1:01:23 PM $664,000 Bidder C 1:01:28 PM $560,000 Bidder B 1:03:10 PM $559,000 Bidder D 1:02:50 PM $558,500 Bidder A 1:03:38 PM $558,300 Bidder E 1:05:12 PM $557,700 Bidder F 1:05:43 PM $557,500 Bidder C 1:06:49 PM $552,000 Bidder G 1:06:55 PM $549,000 [0123] As with the previously discussed market leader format examples, Bidder E no longer receives market feedback after the lowest bid of Bidder E falls out of the required market-leading range.", "Note that compared to the market leader format based on the 2% differential or the top three ranking, Bidder E drops out at a different stage in the sequence of bidding activity when the dollar differential method is utilized.", "[0124] After falling from the market lead based on the dollar differential between the best current bid of Bidder E and the market leading bid, Bidder E may only view more bid history if Bidder E places a new bid low enough to put Bidder E within $10,000 of the market leading bid.", "In the case illustrated in this example, while the bidding activity continued until 1:08:44 PM, Bidder E did not re-bid at any time and so Bidder E did not receive any further feedback about the market-leading bidding activity in the auction 56 .", "EXAMPLE 5 [0125] Market feedback may also be provided in combination such as, for example, providing a bidder 30 with the current rank of that bidder 30 and the next lowest bid.", "Such a format will be referred to herein as a “next horse”", "format.", "By using the next horse format, each bidder 30 may be given information regarding where it stands in the overall bidding and how much its bid must be modified to move up one place in the ranking.", "The bidder 30 may thus gain more information each time it places a bid that is below that of the next ranked bidder 30 .", "The bidder 30 is therefore encouraged to place additional bids and actively participate in the auction 56 , but is not provided with information regarding the lowest bids unless that bidder 30 places a bid that is competitive with the those lowest bids.", "In that way, not only are bidders 30 encouraged to participate actively in the auction 56 , but low bid information is also withheld from those bidders 30 who are not willing to participate actively and competitively in the auction 56 .", "[0126] Thus, in the embodiment considered in this example, the only feedback a particular subject bidder 30 will receive throughout the entire auction 56 is the rank of the current bidder 30 and the value of the bid that is one better than the best bid submitted by the bidder 30 .", "Also in this example, each bidder 30 must submit at least one bid before that bidder 30 will receive any market feedback.", "[0127] [0127 ]FIG. 10 is a flow diagram 300 illustrating an embodiment of the present invention utilizing the next horse format in combination with the requirement that at least one bid must be placed before any information is divulged to a bidder 30 .", "The example provided assumes that a computer processor is executing a set of instructions that perform the steps, however, it will be recognized by one skilled in the art that the instructions may be carried out by any known method.", "At 302 , the auction 56 is commenced and bids are accepted from the bidders 30 .", "The auction 56 normally begins at a scheduled time that is prearranged between the auction coordinator 20 , the purchaser 10 and the bidders 30 .", "At 304 , a bid is received from a bidder 30 .", "That bid may be a bid that is created by a bidder 30 and submitted to the data processing network 77 from the client machine 72 by way of the communications network 73 .", "At 306 , a determination is made as to whether each bidder 30 has qualified as a bid participant by submitting at least one qualified bid.", "At 308 , the rank of each bidder 30 is determined.", "At 310 , each bidder 30 that is a bid participant is provided with the appropriate market feedback which, in this example, includes information related to the best bid submitted by the subject bidder and information related to the bidder ranked one above the current bidder.", "After providing the appropriate market feedback to each bidder 30 , the processor will determine whether the auction closing time has arrived at 312 .", "If the auction closing time has not arrived, the processor will return to 304 to receive additional bids.", "If the auction closing time has arrived, the auction 56 will close and no additional bids will be accepted.", "[0128] FIGS. 11 - 16 illustrate sample screens that are displayed for various participants in a particular auction 56 utilizing the next horse format described in connection with FIG. 10.", "Each of screens 11 - 16 were captured during the same auction 56 after the bids depicted on FIG. 11 were submitted and before any other bids were submitted.", "Thus, screens 11 - 16 illustrate the market feedback that is provided to various participants in a single next horse format auction 56 during a common time period.", "FIG. 11 illustrates a sample of a screen 350 that is displayed to the purchaser 10 .", "At 352 , a lot listing is provided that contains statistics for three lots of transportation services that are being auctioned.", "The first lot is highlighted and is, therefore, active in other portions of the screen 350 .", "At 354 , statistics for all three lots are displayed and at 356 , additional statistics for lot one are displayed.", "A bid history 358 , containing a listing of bids received for lot one is also displayed.", "[0129] [0129 ]FIG. 12 illustrates a sample of a screen 360 that is displayed to a bidder 30 who has not submitted a valid bid for lot one during the course of the auction 56 .", "A lot listing 362 is provided to display market feedback related to the next lowest bid.", "No statistics relating to other bidders 30 are displayed for any of the three lots, indicating that a valid bid has not been placed by the viewing bidder 30 .", "Fields for Next Place Bid 363 and My vs.", "Next 365 are provided in the lot listing 362 .", "Those fields are necessarily different than the fields provided to the purchaser 10 in FIG. 11 or a bidder 30 in the auction 56 illustrated in FIGS. 6 - 8 , because it is important that the purchaser 10 be aware of all bids including the market leading bid and because it has been determined that bidders 30 in the example illustrated in FIGS. 11 - 16 are to be provided less market feedback than bidders 30 in the example illustrated in FIGS. 6 - 8 .", "Also, unlike the lot listing 162 of the screen 160 illustrated in FIG. 7, the lot listing 362 of FIG. 12 does not include a “Best Offering”", "field.", "The “Best Offering”", "field, which appears in FIGS. 7 and 8, may not be utilized in the embodiment illustrated in FIGS. 11 - 16 because, for example, that embodiment does not provide for bidding of different options related to each lot.", "Best offering is furthermore an option that may be utilized or not utilized in any of the embodiments discussed herein.", "[0130] A bid area 364 is provided from which a bid may be submitted.", "Within that bid area 364 are a number of buttons, including a disabled take next button 367 which will be discussed further hereinafter.", "Other buttons for submitting a bid and reloading the last bid submitted are also provided in the bid area 364 .", "At 366 , the bidder 30 is provided with a general status area and at 368 , a status area for the active lot is provided.", "Within the active lot status area 368 , the rank of the viewing bidder is not displayed in the “My Rank”", "field 370 because the viewing bidder has not yet submitted a valid bid for lot one.", "Unlike the active lot status area 168 of FIG. 7, the active lot status area 368 of FIG. 12 does not include a total bid field.", "That is because the total number of bids is not a piece of market feedback that is provided in the embodiment of the next horse format of this example.", "A bid history area 372 provides relevant bid history to the viewing bidder 30 if that viewing bidder 30 has placed a valid bid for the active lot.", "The viewing bidder 30 of screen 360 , however, has not placed a valid bid for the active lot and, therefore, a message stating “bid history is not available until you submit a valid bid in this lot”", "is displayed in the bid history area 372 .", "[0131] [0131 ]FIG. 13 illustrates a sample screen 380 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked fourth in the bidding.", "A lot listing 382 is provided that includes values in the “Next Place Bid”", "field 363 and the “My vs. Next”", "field 365 for lot one.", "Lot one is furthermore active in the remainder of the screen 380 because lot one is the highlighted lot in the lot listing 382 .", "Fields 363 and 365 are displayed because the bidder 30 viewing the screen 380 of FIG. 13 has submitted at least one valid bid for lot one.", "At 384 , the bid area is displayed and the take next button 367 is enabled as indicated by the dark lettering in the take next button 367 .", "At 386 , a general status area is provided for all lots currently being auctioned.", "An active lot status area 388 is provided and includes market feedback regarding the rank of the viewing bidder 30 with regard to lot one because that bidder 30 has placed a valid bid for lot one, which is the active lot.", "A historic bid listing, applicable to the viewer of screen 380 , is provided in the bid history area 390 .", "That bid history includes market feedback for the lowest price bid by the viewing bidder 30 and all higher bids.", "In keeping with the next horse format, the bid history area 390 could provide varying data.", "For example, market feedback related to the next better ranked bidder 30 could be provided in the bid history area 390 since market feedback related to that bidder 30 is already provided in the lot listing 382 .", "Alternately, market feedback related to previously submitted higher bids may or may not be provided in the bid history area 390 when using the next horse format or any other format discussed herein.", "[0132] [0132 ]FIG. 14 illustrates a sample screen 400 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked fifth in the bidding.", "A lot listing 402 is provided that includes values in the “Next Place Bid”", "field 363 and the “My vs. Next”", "field 365 for lot one.", "Lot one is furthermore active in the remainder of the screen 400 because lot one is the highlighted lot in the lot listing 402 .", "Fields 363 and 365 are displayed because the bidder 30 viewing the screen 400 of FIG. 14 has submitted at least one valid bid for lot one.", "A bid area 404 is displayed and the take next button 367 is enabled as indicated by the dark lettering in the take next button 367 .", "At 406 , a general status area is provided for all lots currently being auctioned.", "At 408 , an active lot status area is provided which includes market feedback regarding the rank of the viewing bidder with regard to lot one 30 because that bidder 30 has placed a bid for active lot one.", "A listing of historic bids that is applicable to the viewer of screen 400 is provided in the bid history area 410 .", "That bid history includes market feedback for the lowest price bid by the viewing bidder 30 and all higher bids.", "Thus, the bid history area 410 of FIG. 14 does not include the bid by the fourth ranked bidder that is shown in the bid history area 390 of FIG. 13 because the viewer of screen 400 has a worse ranking than the viewer of screen 380 .", "[0133] [0133 ]FIG. 15 illustrates a sample screen 420 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked second in the bidding.", "A lot listing 422 is provided that includes values in the “Next Place Bid”", "field 363 and the “My vs. Next”", "field 365 for lot one.", "Lot one is furthermore active in the remainder of the screen 420 because lot one is the highlighted lot in the lot listing 422 .", "Fields 363 and 365 are displayed because the bidder 30 viewing the screen 420 of FIG. 15 has submitted at least one valid bid for lot one.", "A bid area 404 is displayed and includes an enabled take next button 367 , as indicated by the dark lettering in the take next button 367 .", "A general status area 426 is provided for all lots currently being auctioned and an active lot status area 428 is provided which includes market feedback regarding the rain of the viewing bidder 30 with regard to lot one because that bidder 30 has placed a bid for active lot one.", "A bid history applicable to the viewer of screen 420 is provided in the bid history area 430 .", "That bid history, like that of the other bidders 30 who have submitted a valid bid in the active lot, includes market feedback for the lowest price bid by the viewing bidder 30 and all higher bids.", "Thus, the bid history area 430 of FIG. 15 includes all bids by the second and worse ranked bidders 30 and the lot listing 422 provides market information for the first place bidder.", "[0134] [0134 ]FIG. 16 illustrates a sample screen 450 that is displayed to a bidder 30 who has submitted at least one valid bid for lot one and is ranked first in the bidding.", "A lot listing 452 is provided that includes values in the “Next Place Bid”", "field 363 and the “My vs. Next”", "field 365 for lot one.", "Lot one is furthermore active in the remainder of the screen 450 because lot one is the highlighted lot in the lot listing 452 .", "Fields 363 and 365 are displayed because the bidder 30 viewing the screen 450 of FIG. 16 has submitted at least one valid bid for lot one.", "A bid area 454 is displayed and the take next button 367 is enabled as indicated by the dark lettering in the take next button 367 .", "At 456 , a general status area is provided for all lots currently being auctioned.", "At 458 , an active lot status area is provided which includes market feedback regarding the rank of the viewing bidder 30 because that bidder 30 has placed a valid bid for active lot one.", "A bid history applicable to the viewer of screen 450 is provided in the bid history area 460 .", "That bid history, like that of the other bidders 30 who have submitted a valid bid, includes market feedback for the lowest amount bid by the viewing bidder 30 and all higher bids.", "Thus, the bid history area 460 of FIG. 16 includes all bids submitted by all bidders 30 .", "[0135] Another example of market feedback that may be provided to a bidder 30 using a next horse format is as follows: after placing its first bid, a bidder 30 in third place will be informed of (i) the value of its current best bid;", "(ii) the fact that it is ranked third in the auction 56 ;", "and (iii) the value of the bid placed by the second ranked bidder 30 .", "Similarly, the bidder 30 in second place will know (i) the value of its current best bid;", "(ii) the fact that it is ranked second in the auction 56 ;", "and (iii) the value of the bid placed by the first ranked bidder 30 .", "[0136] The only way for a bidder 30 to receive market feedback concerning more competitive bids is to place a bid that improves their competitive position in the auction 56 .", "Consider, for example, a situation, wherein Bidder A is ranked fourth and Bidder B is ranked third.", "If Bidder A places a bid that is lower than the that of Bidder B, Bidder A becomes the third ranked bidder 30 and Bidder B becomes the fourth ranked bidder.", "Bidder A is then permitted to view the new third place bid that Bidder A just submitted, as well as the second placed bid.", "That format precludes all but the most aggressive bidders 30 from visibility to true market pricing.", "In fact, the only participants that will know the value of the first placed bid will be the first and second placed bidders 30 .", "[0137] The next horse format may be a particularly risky format for an incumbent bidder 30 .", "Without any real knowledge of how far from the bottom of the market they need to be, an incumbent is taking a substantial risk by not being in the top 1 or 2 bidders 30 .", "EXAMPLE 6 [0138] Consider again the sequence of bidding activity in Table 1, assuming this time that the auction 56 was set up to use a next horse format that provides only information regarding the best bid of that bidder 30 and the next better ranked bidder 30 and does not provide a listing of worse bids that have been placed.", "At 1:04:00 PM, Bidder E would not receive any market feedback because Bidder E has not yet placed any bids.", "Thus, Bidder E is provided with no market feedback at 1:04:00 PM as is shown in Table 18.", "TABLE 18 5.", "Next Horse Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank No bid history is available until a bid has been submitted.", "[0139] At 1:07:49 PM, Bidder E has placed a bid and is in fourth place behind bidders F, C and G. The full bid history (not visible to any of the bidders 30 in this example) is repeated in Table 19.", "TABLE 19 5a.", "Next Horse (1:07:49) Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $123,600 22.62% Bidder B 1:01:23 PM $664,000 $117,600 21.52% Bidder C 1:01:28 PM $560,000 $13,600 2.49% Bidder B 1:03:10 PM $559,000 $12,600 2.31% 7 Bidder D 1:02:50 PM $558,500 $12,100 2.21% 6 Bidder A 1:03:38 PM $558,300 $11,900 2.18% 5 Bidder E 1:05:12 PM $557,700 $11,300 2.07% 4 Bidder F 1:05:43 PM $557,500 $11,100 2.03% Bidder C 1:06:49 PM $552,000 $5,600 1.02% Bidder G 1:06:55 PM $549,000 $2,600 0.48% 3 Bidder C 1:07:22 PM $546,800 $400 0.07% 2 Bidder F 1:07:49 PM $546,400 — 0.00% 1 [0140] In the next horse format of this example at 1:07:49 PM, Bidder E is informed that it is currently in fourth place, and that the third placed bidder 30 has placed a bid of $549,000, which is $8,700 or 1.58% lower than E's current best bid of $557,700 as is shown in Table 20.", "TABLE 20 5a.", "Next Horse (Bidder E) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder E 1:05:12 PM $557,700 $8,700 1.58% 4 Bidder G 1:06:55 PM $549,000 3 [0141] At 1:07:49 PM, Bidder G is informed that it is currently in third place, and that the second ranked bidder has placed a bid of $546,800, which is $2,200 or 0.40% lower than Bidder G's current best bid of $549,000 as is shown in Table 21.", "TABLE 21 5a.", "Next Horse (Bidder G) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:06:55 PM $549,000 $2,200 0.40% 3 Bidder C 1:07:22 PM $546,800 2 [0142] At 1:07:49 PM, Bidder C is informed that it is currently in second place, and that the first placed bidder 30 has placed a bid of $546,400, which is $400 or 0.07% lower than Bidder C's current best bid of $546,800, as is shown in Table 22.", "TABLE 22 5a.", "Next Horse (Bidder C) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:07:22 PM $546,800 $400 0.07% 2 Bidder F 1:07:49 PM $546,400 1 [0143] At 1:07:49 PM, Bidder F is informed that it is currently in first place with a bid of $546,400, as is shown in Table 23.", "TABLE 23 5a.", "Next Horse (Bidder F Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $— 0.00% 1 [0144] At 1:08:02 PM, Bidder C places a new market leading bid moving Bidder C up in rank from second to first place.", "The full bid history (not visible to any of the bidders 30 in this example) is shown in Table 24.", "TABLE 24 5b.", "Next Horse (1:08:02) Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $123,750 22.65% Bidder B 1:01:23 PM $664,000 $117,750 21.56% Bidder C 1:01:28 PM $560,000 $13,750 2.52% Bidder B 1:03:10 PM $559,000 $12,750 2.33% 7 Bidder D 1:02:50 PM $558,500 $12,250 2.24% 6 Bidder A 1:03:38 PM $558,300 $12,050 2.21% 5 Bidder E 1:05:12 PM $557,700 $11,450 2.10% 4 Bidder F 1:05:43 PM $557,500 $11,250 2.06% Bidder C 1:06:49 PM $552,000 $5,750 1.05% Bidder G 1:06:55 PM $549,000 $2,750 0.50% 3 Bidder C 1:07:22 PM $546,800 $550 0.10% Bidder F 1:07:49 PM $546,400 $150 0.03% 2 Bidder C 1:08:02 PM $546,250 $— 0.00% 1 [0145] Bidder C will, therefore, see that it is ranked first at 1:08:02 PM with a bid of $546,250, as is shown in Table 25.", "TABLE 25 5b.", "Next Horse (Bidder C) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:08:02 PM $546,250 $— 0.00% 1 [0146] Bidder F, who has been displaced from first place at 1:08:02 PM, will see that it is in second place at 1:08:02 PM, and that the bidder ranked first has placed a bid of $546,250, which is $150 or 0.03% lower than the best bid of $546,400 placed by Bidder F, as is shown in Table 26.", "TABLE 26 5b.", "Next Horse (Bidder F) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $150 0.03% 2 Bidder C 1:08:02 PM $546,250 1 [0147] At 1:08:02 PM, Bidder G remains in third place but can see that the second placed bidder is now at $546,400, which is $2,600 or 0.48% lower than G's best bid of $549,000.", "Bidder G thus learns that activity between the first and second placed bidders has increased the distance between Bidder G and the market-leading bid, as is shown in Table 27.", "TABLE 27 5b.", "Next Horse (Bidder G) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:06:55 PM $549,000 $2,600 0.48% 3 Bidder F 1:07:49 PM $546,400 2 [0148] Next, consider the situation at 1:08:17 PM.", "Bidder B (previously in seventh place) places a new market-leading bid of $545,000.", "Bidder B is now ranked first.", "The full bid history up until 1:08:17 PM (not visible to any of the bidders 30 in this example) is shown in Table 28.", "TABLE 28 5c.", "Next Horse (1:08:17) Bid vs.", "Market Lead Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $125,000 22.94% Bidder B 1:01:23 PM $664,000 $119,000 21.83% Bidder C 1:01:28 PM $560,000 $15,000 2.75% Bidder B 1:03:10 PM $559,000 $14,000 2.57% Bidder D 1:02:50 PM $558,500 $13,500 2.48% 7 Bidder A 1:03:38 PM $558,300 $13,300 2.44% 6 Bidder E 1:05:12 PM $557,700 $12,700 2.33% 5 Bidder F 1:05:43 PM $557,500 $12,500 2.29% Bidder C 1:06:49 PM $552,000 $7,000 1.28% Bidder G 1:06:55 PM $549,000 $4,000 0.73% 4 Bidder C 1:07:22 PM $546,800 $1,800 0.33% Bidder F 1:07:49 PM $546,400 $1,400 0.26% 3 Bidder C 1:08:02 PM $546,250 $1,250 0.23% 2 Bidder B 1:08:17 PM $545,000 $— 0.00% 1 [0149] At 1:08:17 PM, Bidder C, who has been displaced from first place, will see that it are now in second place, and that the first placed bidder has placed a bid of $545,000, which is $1,250 or 0.23% lower than C's best bid of $546,250, as is shown in Table 29.", "TABLE 29 5c.", "Next Horse (Bidder C) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:08:02 PM $546,250 $1,250 0.23% 2 Bidder B 1:08:17 PM $545,000 1 [0150] Bidder F has been displaced from second place and now ranks third.", "Although the ranking has changed, in all other respects F sees the same feedback.", "The second placed bidder 30 is at $546,250, which is $150 or 0.03% lower than Bidder F's best bid of $546,400, as is shown in Table 30.", "TABLE 30 5c.", "Next Horse (Bidder F) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $150 0.03% 3 Bidder C 1:08:02 PM $546,250 2 [0151] At 1:08:17 PM, Bidder G faces a situation similar to that of Bidder F. Bidder G has been displaced from third place and now ranks fourth overall, but the feedback with respect to the next placed bidder is the same.", "The third placed bidder is at $546,400, which is $2,600 or 0.48% lower than G's best bid of $549,000, as is shown in Table 31.", "TABLE 31 5c.", "Next Horse (Bidder G;", "1:08:17) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:06:55 PM $549,000 $2,600 0.48% 4 Bidder F 1:07:49 PM $546,400 3 [0152] At 1:08:44 PM, Bidder G decides to lower its bid by $7,000.", "That places Bidder G in first place.", "The full bid history (not visible to any of the bidders 30 in this example) is shown in Table 32.", "TABLE 32 5d.", "Next Horse (1:08:44) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder A 1:02:45 PM $670,000 $128,000 23.62% Bidder B 1:01:23 PM $664,000 $122,000 22.51% Bidder C 1:01:28 PM $560,000 $18,000 3.32% Bidder B 1:03:10 PM $559,000 $17,000 3.14% Bidder D 1:02:50 PM $558,500 $16,500 3.04% 7 Bidder A 1:03:38 PM $558,300 $16,300 3.01% 6 Bidder E 1:05:12 PM $557,700 $15,700 2.90% 5 Bidder F 1:05:43 PM $557,500 $15,500 2.86% Bidder C 1:06:49 PM $552,000 $10,000 1.35% Bidder G 1:06:55 PM $549,000 $7,000 1.29% Bidder C 1:07:22 PM $546,800 $4,800 0.89% Bidder F 1:07:49 PM $546,400 $4,400 0.81% 4 Bidder C 1:08:02 PM $546,250 $4,250 0.78% 3 Bidder B 1:08:17 PM $545,000 $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000 $— 0.00% 1 [0153] At 1:08:44 PM, Bidder G is provided with the market feedback shown in Table 33.", "TABLE 33 5d.", "Next Horse (Bidder G;", "1:08:44) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder G 1:08:44 PM $542,000 $— 0.00% 1 [0154] Thus, at 1:08:44 PM Bidder B has been displaced from first place.", "Bidder B will, therefore, see that it is now ranked second and that the first placed bidder has placed a bid of $542,000, which is $3,000 or 0.55% lower than B's bid of $545,000.", "The market feedback provided to Bidder B at 1:08:44 PM is illustrated in Table 34.", "TABLE 34 5d.", "Next Horse (Bidder B;", "1:08:44) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder B 1:08:17 PM $545,000 $3,000 0.55% 2 Bidder G 1:08:44 PM $542,000 1 [0155] At 1:08:44 PM, Bidder C sees the same feedback as before, except that the rank of Bidder C has now slipped from second to third place.", "Bidder C will, however, be advised that the second placed bidder is at $545,000, which is $1,250 or 0.23% lower than the lowest bid submitted by Bidder C, which is $546,250.", "The market feedback provided to Bidder C at 1:08:44 PM is illustrated in Table 35.", "TABLE 35 Next Horse (Bidder C;", "1:08:44) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder C 1:08:02 PM $546,250 $1,250 0.23% 3 Bidder B 1:08:17 PM $545,000 2 [0156] At 1:08:44 PM, Bidder F would view the market feedback shown in Table 36 and the remaining bidders 30 would also be provided with market feedback according to the next horse format utilized in this example.", "TABLE 36 5d.", "Next Horse (Bidder F;", "1:08:44) Bid vs.", "Next Horse Bidder Bid Time Bid $ % Rank Bidder F 1:07:49 PM $546,400 $150 0.03% 4 Bidder C 1:08:02 PM $546,250 3 [0157] Other combinations of market feedback may also be provided in connection with the next horse format.", "For example, as previously described, in certain embodiments of the next horse market feedback format, not only is information provided for the next better bid, information related to all worse bids is also provided.", "[0158] Auctions 56 , and particularly online auctions 56 , can be fast paced, requiring bidders 30 to make important decisions about whether to submit an additional bid to better that of another bidder 30 .", "In many auctions 56 bettering a bid placed by another bidder 30 may not be as simple as placing a bid that is one dollar less than that placed by the other bidder 30 .", "For example, to avoid the submission of many bids that better each other by very small amounts, purchasers 10 may require that bidders 30 place a minimum differential bid to better that of the next higher ranked bidder 30 , another higher ranked bidder 30 , or the market leading bidder 30 .", "[0159] Thus, for example, if Bidder A has placed a best bid of $ 52 , 000 in a reverse auction 56 , Bidder B has placed the next better ranked bid with a bid of $550,000, and the minimum differential bid required is $ 500 , then Bidder A would have to submit a bid of no more than $49,500 to move up one place in the ranking.", "Because bids are not always submitted in such round numbers and time allowed to calculate and place another bid, particularly near the closing of an auction 56 , can be short, it is beneficial to include in the auction 56 a facility for calculating and/or submitting the maximum amount that would place the bidder 30 at a desired rank.", "The present invention, therefore, may include one or more facilities for automatically calculating the maximum amount that may be bid to place a bidder 30 at a desired rank in a reverse auction.", "Of course, such a minimum differential may also be applied to a forward auction and a facility that adds the minimum differential to a better ranked bid would be equally applicable.", "EXAMPLE 7 [0160] In a certain embodiment of the invention, wherein the next horse format is utilized such that only the amount bid by the next better bidder 30 and current rankng is known to each bidder 30 , a “take next rank”", "facility may be provided in the auction software.", "That take next rank facility may take the form of a button that may be depressed or a selectable button that is displayed on the screen of the bidder 30 .", "An example of such a button is illustrated on FIGS. 12 - 16 at reference number 367 and is labeled “Take Next.”", "[0161] Selection of the take next rank button or a similar take higher rank button (not illustrated) may perform several functions including, for example, calculating of the maximum amount that must be bid to attain the next higher rank, and submitting that amount as a bid.", "[0162] Selection of the take next rank button or take higher rank button may alternately only calculate the maximum amount that must be bid to attain the next higher rank.", "In that format, the bidder 30 may have the amount required for the next bid provided quickly and accurately and then consider whether to place a bid equal to the calculated amount, place a bid for a lesser amount, or choose not to place a bid that moves that bidder 30 up to the next rank.", "[0163] A select higher rank facility may also or alternately be provided.", "In one embodiment, selection of the take higher rank button will calculate the maximum amount that must be bid to attain one selected higher rank.", "In another embodiment, the take higher rank button will calculate the maximum bid required to take all higher ranks.", "[0164] Referring to FIG. 12, the take next button 367 is dimmed indicating that the button is disabled and, therefore, may not be selected.", "The take next button 367 of FIG. 12 is disabled because the bidder 30 viewing the screen 360 of FIG. 12 has not yet submitted a valid bid for lot one which is selected in the lot listing 362 .", "The take next button 367 may be enabled for a bidder 30 that has not yet placed a bid, for example, to provide an amount that must be bid to overtake the lowest ranked bidder 30 .", "Enabling the take next button 367 for a non-participating bidder 30 , however, permits that non-participating bidder 30 to view market feedback related to the lowest bidder 30 .", "Thus, in the embodiment illustrated in FIG. 12, the viewing bidder 30 is not permitted to utilize the take next button 367 because the rules for that auction 56 are defined such that no market feedback is permitted to be viewed until a bidder 30 has placed a valid bid.", "Therefore, in the embodiment illustrated in FIG. 12, the viewing bidder 30 must place a bid prior to being permitted to utilize the take next button 367 .", "[0165] Referring to FIGS. 13 - 16 , the take next button 367 is displayed and enabled.", "In accordance with the rules that are employed in the embodiment illustrated in those Figures, the take next button 367 is enabled because the bidders 30 viewing the screens 380 , 400 , 420 , and 450 of those Figures are permitted to use the take next button 367 because they have submitted at least one bid for the active lot.", "The auction 56 displayed in FIGS. 11 - 16 is an index type auction 56 wherein the amount bid is added to a predetermined index price.", "Thus a bid of 10 .", "00 might indicate a bid of 10.00% over the index price, while a bid of −0.30 might indicate a bid of 0.30% under the index price.", "Thus, the viewer of screen 380 , for example, may select the take next button by, for example using a mouse, keyboard, or touch screen.", "As may be seen in the lot listing 382 , the next better bid is 4.75 which is 4.25 less than the best bid submitted by the viewing bidder 30 .", "If, for example, the minimum differential for the auction 56 depicted on screen 380 is 0.1, then selection of the take next button 367 would provide a value of 4.65 which is equal to the value of the next better bid of 4.75 less the minimum differential of 0.10.", "EXAMPLE 8 [0166] Tables 37-41 illustrate a reserve price format of the invention that takes into consideration the setting of a reserve price as discussed hereinbefore.", "In that format, bidders 30 do not view any market feedback unless their current best bid is below the reserve price.", "That format rewards bidders 30 who have made a minimum commitment to pursue an award by bidding below the reserve price.", "Thus, no market feedback is made available to bidders 30 who have not submitted a bid below the reserve price threshold, thereby limiting or eliminating disclosure of price sensitive information to bidders 30 who merely watch the auction 56 without participating therein.", "The reserve price format, therefore, may beneficially be used to inform all participants that the reserve price is a serious threshold which bidders 30 must meet before the purchaser 10 is willing to consider an award of the business to a non-incumbent.", "The reserve price format also puts pressure on incumbents to at least meet the reserve price once other bidders 30 have bid below the reserve price.", "[0167] Referring again to the sequence of bidding activity in FIG. 1, the following example assumes that the auction 56 is taking place in the reserve price format and the reserve price is set at $555,000.", "At 1:06:00 PM the complete bid history (not visible to any bidder 30 in this example) is repeated below in Table 37.", "TABLE 37 6.", "Below Reserve Only (1.06:00 PM) Bid vs Reserve Bid vs.", "Market Lead Bidder Bid Time Bid Reserve $ % $ % Rank Bidder A 1:02:45 PM $670,000 $555,000 $115,000 20.72% $112,500 20 18% Bidder B 1:01:23 PM $664.000 $555,000 $109,000 19.64% $106,500 19.10% Bidder C 1:01:28 PM $560,000 $555,000 $ 5,000 0 90% $ 2,500 0.45% 6 Bidder B 1:03:10 PM $559,000 $555,000 $ 4,000 0.72% $ 1,500 0.27% 5 Bidder D 1:02:50 PM $558,500 $555,000 $ 3,500 0.63% $ 1,000 0.18% 4 Bidder A 1:03:38 PM $558,300 $555,000 $ 3,300 0.59% $ 800 0.14% 3 Bidder E 1:05:12 PM $557,700 $555.000 $ 2,700 0.49% $ 200 0.04% 2 Bidder F 1:05:43 PM $557,500 $555,000 $ 2,500 0 45% $ — 0.00% 1 [0168] Following Bidder E to illuminate the operation of the reserve price format, at 1:06:00 PM Bidder E has placed one bid of $557,700 at 1:05:12 PM.", "Since that bid is above the reserve price, Bidder E does not receive any feedback about the remainder of the bidding activity in the auction 56 , as shown in Table 38.", "TABLE 38 6.", "Below Reserve Only (Bidder E) Bid vs.", "Reserve Bidder Bid Time Bid Reserve $ % Bidder E 1:05:12 PM $557,500 $555,000 $2,700 0.49% [0169] As may be seen by reference to Table 1, Bidder E did not submit any further bids in the auction 56 , and so does not receive any further market feedback during the auction 56 .", "In contrast, at 1:06:00 PM Bidder F has submitted only one bid of $557,500.", "Like Bidder E, Bidder F will receive no market feedback at 1:06:00 PM because the lowest submitted bid of Bidder F is above the reserve price.", "Thus, at 1:06:00 PM, Bidder F would view the information provided in Table 39.", "TABLE 39 6.", "Below Reserve Only (Bidder F) Bid vs.", "Reserve Bidder Bid Time Bid Reserve $ % Bidder F 1:05:43 PM $557,500 $555,000 $2,500 0.45% [0170] However, unlike Bidder E, Bidder F submits a bid of $546,400 at 1:07:49 PM.", "That bid is below the reserve price of $555,000 and, accordingly, Bidder F sees the full bid history as shown below in Table 40 after the 1:07:49 PM bid is placed.", "At 1:07:49 PM, Bidder F is able to sec that it is ranked first, and also becomes aware through the market feedback that there are two other bidders 30 who are below reserve price and within $3,000 or 0.5% of the current best bid of Bidder F. Although the identity of the other participants is not visible in this example, Bidder F would also see that there are six other bidders 30 participating in the auction 56 and that a total of twelve bids have been placed thus far in the auction 56 .", "TABLE 40 6.", "Below Reserve Only (Bidder F) Bid vs Reserve Bid vs.", "Market Lead Bidder Bid Time Bid Reserve $ % $ % Rank Bidder A 1:02.45 PM $670,000 $555.000 $115,000 20.72% $123,600 22.62% Bidder B 1:01:23 PM $664,000 $555,000 $109,000 19.64% $117,600 21.52% Bidder C 1:01:28 PM $560,000 $555,000 $ 5,000 0 90% $ 13,600 2.49% Bidder B 1:03:10 PM $559,000 $555,000 $ 4,000 0.72% $ 12,600 2.31% 7 Bidder D 1:02:50 PM $558,500 $555,000 $ 3,500 0.63% $ 12,100 2.21% 6 Bidder A 1:03:38 PM $558,300 $555,000 $ 3,300 0.59% $ 11,900 2.18% 5 Bidder E 1:05:12 PM $557,700 $555,000 $ 2,700 0.49% $ 11,300 2.07% 4 Bidder F 1:05:43 PM $557,500 $555,000 $ 2,500 0.45% $ 11,100 2.03% Bidder C 1:06:49 PM $552,000 $555,000 $ (3,000) −0.54% $ 5,600 1.02% Bidder G 1:06:55 PM $549,000 $555,000 $ (6,000) −1.08% $ 2,600 0.48% 3 Bidder C 1:07:22 PM $546,800 $555,000 $ (8,200) −1.48% $ 400 0.07% 2 Bidder F 1:07:49 PM $546,400 $555,000 $ (8,600) −1 55% $ — 0 00% 1 [0171] Bidder F is entitled to view the bid history, for the remainder of the auction 56 in this example, because Bidder F has submitted a bid less than the reserve price as required to see that market feedback.", "As may be seen by reference to Table 1, Bidder F does not submit any additional bids during the auction 56 and, thus, falls back to fourth place by the time the auction 56 ends at 1:08:44 PM.", "The market feedback that Bidder F will see at 1:08:44 PM is shown in Table 41.", "TABLE 41 6.", "Below Reserve Only (Bidder F) Bid vs Reserve Bid vs Market Lead Bidder Bid Time Bid Reserve $ % $ % Rank Bidder A 1:02:45 PM $670,000 $555,000 $115,000 20 72% $128,000 23.62% Bidder B 1:01:23 PM $664,000 $555,000 $109,000 19 64% $122,000 22 51% Bidder C 1:01:28 PM $560,000 $555,000 $ 5,000 0.90% $ 18,000 3.32% Bidder B 1:03:10 PM $559,000 $555,000 $ 4,000 0.72% $ 17,000 3.14% Bidder D 1:02:50 PM $558,500 $555,000 $ 3,500 0.63% $ 16,500 3.04% Bidder A 1:03:38 PM $558,300 $555,000 $ 3,300 0.59% $ 16,300 3.01% 6 Bidder E 1:05:12 PM $557,700 $555,000 $ 2,700 0.49% $ 15,700 2.90% 5 Bidder F 1:05:43 PM $557,500 $555,000 $ 2,500 0.45% $ 15,500 2.86% Bidder C 1:06:49 PM $552,000 $555,000 $ (3,000) −0 54% $ 10,000 1.85% Bidder G 1:06:55 PM $549,000 $555,000 $ (6,000) −1.08% $ 7,000 1.29% Bidder C 1.07:22 PM $546,800 $555,000 $ (8,200) −1.48% $ 4,800 0.89% Bidder F 1:07:49 PM $546,400 $555,000 $ (8,600) −1.55% $ 4,400 0.81% 4 Bidder C 1:08:02 PM $546,250 $555,000 $ (8,750) −1.58% $ 4,250 0.78% 3 Bidder B 1:08:17 PM $545,000 $555,000 $ (10,000) −1 80% $ 3,000 0.55% 2 Bidder G 1:08:44 PM $542,000 $555,000 $ (13,000) −2.34% $ — 0.00% 1 [0172] Other differential feedback technology and differential feedback rules could also be applied to such a reserve price formatted auction 56 .", "For example, rather than providing no market feedback to bidders 30 that have not bid below the reserve price, the auction 56 could provide limited market feedback to those bidders 30 and full market feedback to bidders 30 who have bid below reserve.", "The limited feedback might include, for example, rank only or bid history of all the bids placed by bidders 30 that are above the reserve price but not any of the bids below reserve price.", "In the latter example, a bidder 30 who has not placed a bid below the reserve price would lose access to market feedback from those bidders 30 bidding below the reserve price until that bidder 30 also places a bid below reserve price.", "[0173] In another embodiment, the market leader format may be combined with the reserve price format to provide additional incentive to bidders 30 to continue bidding aggressively after they have crossed the reserve price threshold.", "For example, bid history might only be visible to participants who (i) have bid below reserve price;", "and (ii) are ranked in, for example, the top three bidders 30 .", "[0174] Alternatively, bid history might be visible to all bidders 30 below reserve until there are at least, for example, three bidders 30 below that have placed bids below the reserve price.", "Once more than three bidders 30 have bid below the reserve price in that example, only the top three bidders 30 would continue to view the full bid history.", "[0175] While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.", "In particular, it should be noted that while the auction functions described above have been described in the context of downward pricing auctions, the auction functions can be equally applied to upward pricing auctions.", "Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents." ]
BACKGROUND OF THE INVENTION 1. Technical Field The present invention relates generally to security in a computer system, and particularly to limiting vulnerability to attacks on a partitioned computer system. 2. Description of Related Art As security issues become a greater concern, the IT industry is undergoing a rapid transformation to enhance security in all aspects. Currently a number of nations have embraced the Common Criteria Evaluation methodologies, a rigorous and expensive methodology used to evaluate the security assurance level that a IT system possesses. This methodology encompasses all aspects of IT product development, ranging from building security where development activities take place, CM systems, development activities, and up to and including secure delivery of the product to prevent tampering. Currently the US government requires this evaluation to be completed for all IT equipment used in national security, critical infrastructure and Homeland Defense systems. Additionally the financial and healthcare industries are embracing these evaluations as part of the proposed requirements for their systems to be purchased. Current hypervisor designs have exposed external interfaces to provide general services (non-hardware specific) to the operating systems loaded such as interrupt management, Page Table Entry (PTE) management, Translation Control Entry (TCE) management as well as specialized interfaces to handle specialized hardware resources such as Federation or InfiniBand (IB) adapters. FIG. 3 shows a known system for platform firmware, such as Hypervisor. Hypervisor is available from International Business Machines Corporation. Hypervisor 302 includes Hypervisor I/F 304 which allows access to Hypervisor calls (H_calls) for various partitions 310 , 312 , 314 . Depending on the particular adapter hardware, some calls are hardware dependent 308 while some calls are non-hardware dependent 306 . All types of partitions are presented with both types of interface. Currently International Business Machines is introducing the first of a converged hypervisor design that supports multiple different simultaneous operating systems on a single platform. In this hypervisor design, multiple operating systems are allowed to access all hypervisor calls, H_CALLS, through hypervisor interface. In the current design there are more than 350 hypervisor calls, some dedicated to RPA partitions (of the RS/6000 platform architecture), some dedicated to OS/400 partitions and some shared. In the current product plans it is well understood that the majority of systems will only support RPA partitions because the industry is moving away from proprietary OSs like OS/400. The majority of delivered systems will only use AIX or Linux partitions and therefore the exposed hypervisor interfaces specific to OS/400 partitions represent vulnerable attack points that have no product value in RPA only systems. Conversely the customers needing OS/400 partitions most likely will not use RPA partitions at the same time, those customers using both RPA and non-RPA partitions on the same system is only a very small percentage of the overall market. In the current systems only a few platforms support the Federation adapter and plans for the InfiniBand adapter are for a small percentage of system, however all platforms have hypervisor calls for these adapters exposed. In the p6xx series, from the p625, p630, p640, p650, p655, p670, and p690, only the p670 and p690 provide hardware support for the Federation adapters and only a very small percentage of p670 and p690 systems are shipped with the Federation adapters. These interfaces represent unused unnecessary attack points when the adapters are not installed. An analysis of the security of a system shows that the exposed external interfaces are the attack points for external threats, increase the number of interfaces and vulnerability increases. Additionally analysis has shown and is well documented in many publications that there is approximately one security flaw in every KLOC (thousand lines of code) of delivered code. According to an excerpt taken from the Trusted Computing Group's Backgrounder of May 2003: A critical problem being addressed by creation and use of these specifications is the increasing threat of software attack due to a combination of increasingly sophisticated and automated attack tools, the rapid increase in the number of vulnerabilities being discovered, and the increasing mobility of users. The large number of vulnerabilities is due, in part, to the incredible complexity of modern systems. For example, a typical Unix or Windows system, including major applications, represents on the order of 100 million lines of code. Recent studies have shown that typical product level software has roughly one security related bug per thousand of lines of source code. Thus, a typical system will potentially have one hundred thousand security bugs. Current plans for the POWER5 LPAR platform are to undergo a complete security evaluation to meet the EAL4+ Common Criteria requirements. In review of the previous platform evaluation, two critical areas are interpartition protection and access control between partitions. The exposure of additional unused interfaces represents a significant increase in vulnerability during the use of these systems as well as an increase in the testing efforts. Current solutions to this problem is to include code in each and every H_CALL (hypervisor call) dedicated to the specialized hardware that looks for adapter presence and/or checks to see if the adapter has been initialized. This requires code in many routines as opposed to having a single immediate exit point. Therefore, it would be advantageous to have an improved method and apparatus for enhancing access security to hypervisor calls by partitioned systems. SUMMARY OF THE INVENTION The present invention provides a method, apparatus, and computer instructions to reduce external access to partitions in a computer system, thereby reducing the possibility of attacks. In a preferred embodiment, addresses for calls are used to fill a table, where the addresses are specifically selected for a requesting computer. For example, in one embodiment, a routine searches for the adapter type of a requesting computer and populates the table with calls specific to that type of adapter. Other types of calls are not put in the table. Instead, those calls are replaced by routines that will return an error. In other embodiments, the operating system type is used to determine what addresses are used to populate the table. These and other embodiments are explained more fully below. BRIEF DESCRIPTION OF THE DRAWINGS The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: FIG. 1 is a block diagram of a data processing system in which the present invention may be implemented; FIG. 2 is a block diagram of an exemplary logical partitioned platform in which the present invention may be implemented; FIG. 3 shows a known partitioned data processing system with hypervisor where each partition can be accessed by each type of call. FIG. 4 shows a static table and a dynamic table for holding hypervisor call addresses consistent with a preferred embodiment of the present invention. FIG. 5 shows a static table and a dynamic table where some of the dynamic table entries are filled with routines that return an error, consistent with a preferred embodiment of the present invention. FIG. 6 shows a flowchart with process steps for implementing a preferred embodiment of the present invention. FIG. 7 shows a hypervisor and partitions for a computer system where all partitions are visible. FIG. 8 shows a hypervisor and partitions where one partition is hidden from external calling, consistent with a preferred embodiment of the present invention. FIG. 9 shows a hypervisor and partitions where two partitions are hidden from external calling, consistent with a preferred embodiment of the present invention. FIG. 10 shows static and dynamic tables consistent with implementing a preferred embodiment of the present invention. FIG. 11 shows a flowchart with process steps for implementing a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now to the figures, and in particular with reference to FIG. 1 , a block diagram of a data processing system in which the present invention may be implemented is depicted. Data processing system 100 may be a symmetric multiprocessor (SMP) system including a plurality of processors 101 , 102 , 103 , and 104 connected to system bus 106 . For example, data processing system 100 may be an IBM eServer, a product of International Business Machines Corporation in Armonk, N.Y., implemented as a server within a network. Alternatively, a single processor system may be employed. Also connected to system bus 106 is memory controller/cache 108 , which provides an interface to a plurality of local memories 160 - 163 . I/O bus bridge 110 is connected to system bus 106 and provides an interface to I/O bus 112 . Memory controller/cache 108 and I/O bus bridge 110 may be integrated as depicted. Data processing system 100 is a logical partitioned (LPAR) data processing system. Thus, data processing system 100 may have multiple heterogeneous operating systems (or multiple instances of a single operating system) running simultaneously. Each of these multiple operating systems may have any number of software programs executing within it. Data processing system 100 is logically partitioned such that different PCI I/O adapters 120 - 121 , 128 - 129 , and 136 , graphics adapter 148 , and hard disk adapter 149 may be assigned to different logical partitions. In this case, graphics adapter 148 provides a connection for a display device (not shown), while hard disk adapter 149 provides a connection to control hard disk 150 . Thus, for example, suppose data processing system 100 is divided into three logical partitions, P 1 , P 2 , and P 3 . Each of PCI I/O adapters 120 - 121 , 128 - 129 , 136 , graphics adapter 148 , hard disk adapter 149 , each of host processors 101 - 104 , and memory from local memories 160 - 163 is assigned to each of the three partitions. In these examples, memories 160 - 163 may take the form of dual in-line memory modules (DIMMs). DIMMs are not normally assigned on a per DIMM basis to partitions. Instead, a partition will get a portion of the overall memory seen by the platform. For example, processor 101 , some portion of memory from local memories 160 - 163 , and I/O adapters 120 , 128 , and 129 may be assigned to logical partition P 1 ; processors 102 - 103 , some portion of memory from local memories 160 - 163 , and PCI I/O adapters 121 and 136 may be assigned to partition P 2 ; and processor 104 , some portion of memory from local memories 160 - 163 , graphics adapter 148 and hard disk adapter 149 may be assigned to logical partition P 3 . Each operating system executing within data processing system 100 is assigned to a different logical partition. Thus, each operating system executing within data processing system 100 may access only those I/O units that are within its logical partition. Thus, for example, one instance of the Advanced Interactive Executive (AIX) operating system may be executing within partition P 1 , a second instance (image) of the AIX operating system may be executing within partition P 2 , and a Linux or OS/400 operating system may be operating within logical partition P 3 . Peripheral component interconnect (PCI) host bridge 114 connected to I/O bus 112 provides an interface to PCI local bus 115 . A number of PCI input/output adapters 120 - 121 may be connected to PCI bus 115 through PCI-to-PCI bridge 116 , PCI bus 118 , PCI bus 119 , I/O slot 170 , and I/O slot 171 . PCI-to-PCI bridge 116 provides an interface to PCI bus 118 and PCI bus 119 . PCI I/O adapters 120 and 121 are placed into I/O slots 170 and 171 , respectively. Typical PCI bus implementations will support between four and eight I/O adapters (i.e. expansion slots for add-in connectors). Each PCI I/O adapter 120 - 121 provides an interface between data processing system 100 and input/output devices such as, for example, other network computers, which are clients to data processing system 100 . An additional PCI host bridge 122 provides an interface for an additional PCI bus 123 . PCI bus 123 is connected to a plurality of PCI I/O adapters 128 - 129 . PCI I/O adapters 128 - 129 may be connected to PCI bus 123 through PCI-to-PCI bridge 124 , PCI bus 126 , PCI bus 127 , I/O slot 172 , and I/O slot 173 . PCI-to-PCI bridge 124 provides an interface to PCI bus 126 and PCI bus 127 . PCI I/O adapters 128 and 129 are placed into I/O slots 172 and 173 , respectively. In this manner, additional I/O devices, such as, for example, modems or network adapters may be supported through each of PCI I/O adapters 128 129 . In this manner, data processing system 100 allows connections to multiple network computers. A memory mapped graphics adapter 148 inserted into I/O slot 174 may be connected to I/O bus 112 through PCI bus 144 , PCI-to-PCI bridge 142 , PCI bus 141 and PCI host bridge 140 . Hard disk adapter 149 may be placed into I/O slot 175 , which is connected to PCI bus 145 . In turn, this bus is connected to PCI-to-PCI bridge 142 , which is connected to PCI host bridge 140 by PCI bus 141 . A PCI host bridge 130 provides an interface for a PCI bus 131 to connect to I/O bus 112 . PCI I/O adapter 136 is connected to I/O slot 176 , which is connected to PCI-to-PCI bridge 132 by PCI bus 133 . PCI-to-PCI bridge 132 is connected to PCI bus 131 . This PCI bus also connects PCI host bridge 130 to the service processor mailbox interface and ISA bus access pass-through logic 194 and PCI-to-PCI bridge 132 . Service processor mailbox interface and ISA bus access pass-through logic 194 forwards PCI accesses destined to the PCI/ISA bridge 193 . NVRAM storage 192 is connected to the ISA bus 196 . Service processor 135 is coupled to service processor mailbox interface and ISA bus access pass-through logic 194 through its local PCI bus 195 . Service processor 135 is also connected to processors 101 - 104 via a plurality of JTAG/I 2 C busses 134 . JTAG/I 2 C busses 134 are a combination of JTAG/scan busses (see IEEE 1149.1) and Phillips I 2 C busses. However, alternatively, JTAG/I 2 C busses 134 may be replaced by only Phillips I 2 C busses or only JTAG/scan busses. All SP-ATTN signals of the host processors 101 , 102 , 103 , and 104 are connected together to an interrupt input signal of the service processor. The service processor 135 has its own local memory 191 , and has access to the hardware OP-panel 190 . When data processing system 100 is initially powered up, service processor 135 uses the JTAG/I 2 C busses 134 to interrogate the system (host) processors 101 - 104 , memory controller/cache 108 , and I/O bridge 110 . At completion of this step, service processor 135 has an inventory and topology understanding of data processing system 100 . Service processor 135 also executes Built-In-Self-Tests (BISTs), Basic Assurance Tests (BATs), and memory tests on all elements found by interrogating the host processors 101 - 104 , memory controller/cache 108 , and I/O bridge 110 . Any error information for failures detected during the BISTS, BATs, and memory tests are gathered and reported by service processor 135 . If a meaningful/valid configuration of system resources is still possible after taking out the elements found to be faulty during the BISTs, BATs, and memory tests, then data processing system 100 is allowed to proceed to load executable code into local (host) memories 160 - 163 . Service processor 135 then releases host processors 101 - 104 for execution of the code loaded into local memory 160 - 163 . While host processors 101 - 104 are executing code from respective operating systems within data processing system 100 , service processor 135 enters a mode of monitoring and reporting errors. The type of items monitored by service processor 135 include, for example, the cooling fan speed and operation, thermal sensors, power supply regulators, and recoverable and non-recoverable errors reported by processors 101 - 104 , local memories 160 - 163 , and I/O bridge 110 . Service processor 135 is responsible for saving and reporting error information related to all the monitored items in data processing system 100 . Service processor 135 also takes action based on the type of errors and defined thresholds. For example, service processor 135 may take note of excessive recoverable errors on a processor's cache memory and decide that this is predictive of a hard failure. Based on this determination, service processor 135 may mark that resource for deconfiguration during the current running session and future Initial Program Loads (IPLs). IPLs are also sometimes referred to as a “boot” or “bootstrap”. Data processing system 100 may be implemented using various commercially available computer systems. For example, data processing system 100 may be implemented using IBM eServer iSeries Model 840 system available from International Business Machines Corporation. Such a system may support logical partitioning using an OS/400 operating system, which is also available from International Business Machines Corporation. Those of ordinary skill in the art will appreciate that the hardware depicted in FIG. 1 may vary. For example, other peripheral devices, such as optical disk drives and the like, also may be used in addition to or in place of the hardware depicted. The depicted example is not meant to imply architectural limitations with respect to the present invention. With reference now to FIG. 2 , a block diagram of an exemplary logical partitioned platform is depicted in which the present invention may be implemented. The hardware in logical partitioned platform 200 may be implemented as, for example, data processing system 100 in FIG. 1 . Logical partitioned platform 200 includes partitioned hardware 230 , operating systems 202 , 204 , 206 , 208 , and partition management firmware 210 . Operating systems 202 , 204 , 206 , and 208 may be multiple copies of a single operating system or multiple heterogeneous operating systems simultaneously run on logical partitioned platform 200 . These operating systems may be implemented using OS/400, which are designed to interface with a partition management firmware, such as Hypervisor. OS/400 is used only as an example in these illustrative embodiments. Of course, other types of operating systems, such as AIX and linux, may be used depending on the particular implementation. Operating systems 202 , 204 , 206 , and 208 are located in partitions 203 , 205 , 207 , and 209 . Hypervisor software is an example of software that may be used to implement platform (in this example, partition management) firmware 210 and is available from International Business Machines Corporation. Firmware is “software” stored in a memory chip that holds its content without electrical power, such as, for example, read-only memory (ROM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), and nonvolatile random access memory (nonvolatile RAM). Additionally, these partitions also include partition firmware 211 , 213 , 215 , and 217 . Partition firmware 211 , 213 , 215 , and 217 may be implemented using initial boot strap code, IEEE-1275 Standard Open Firmware, and runtime abstraction software (RTAS), which is available from International Business Machines Corporation. When partitions 203 , 205 , 207 , and 209 are instantiated, a copy of boot strap code is loaded onto partitions 203 , 205 , 207 , and 209 by platform firmware 210 . Thereafter, control is transferred to the boot strap code with the boot strap code then loading the open firmware and RTAS. The processors associated or assigned to the partitions are then dispatched to the partition's memory to execute the partition firmware. Partitioned hardware 230 includes a plurality of processors 232 - 238 , a plurality of system memory units 240 - 246 , a plurality of input/output (I/O) adapters 248 - 262 , and a storage unit 270 . Each of the processors 232 - 238 , memory units 240 - 246 , NVRAM storage 298 , and I/O adapters 248 - 262 may be assigned to one of multiple partitions within logical partitioned platform 200 , each of which corresponds to one of operating systems 202 , 204 , 206 , and 208 . Platform firmware 210 performs a number of functions and services for partitions 203 , 205 , 207 , and 209 to create and enforce the partitioning of logical partitioned platform 200 . Platform firmware 210 is a firmware implemented virtual machine identical to the underlying hardware. Thus, platform firmware 210 allows the simultaneous execution of independent OS images 202 , 204 , 206 , and 208 by virtualizing all the hardware resources of logical partitioned platform 200 . Service processor 290 may be used to provide various services, such as processing of platform errors in the partitions. These services also may act as a service agent to report errors back to a vendor, such as International Business Machines Corporation. Operations of the different partitions may be controlled through a hardware management console, such as hardware management console 280 . Hardware management console 280 is a separate data processing system from which a system administrator may perform various functions including reallocation of resources to different partitions. FIG. 4 shows a set of tables consistent with implementing a preferred embodiment of the present invention. In a first preferred embodiment, the present invention dynamically restricts the number of external hypervisor interfaces presented based on the presence of specialized hardware adapters installed in the requesting computer. By restricting access by an external computer to certain hypervisor calls, access to certain partitions behind the hypervisor is restricted. In this example, static table 402 includes all H_call addresses. H_calls, or hypervisor calls, are services used by partition firmware. As RTAS instantiation (run time abstraction services) happens, all RTAS calls in SMP mode are routed to the hypervisor using H_calls. These calls are not exposed to the operating system and are subject to change at the convenience of the hypervisor and/or partition firmware. Examples of H_calls include h_get_xive, which is called by pSeries firmware to get the contents of the xive interrupt control register; and h_pci_config_read, which reads the PCI adapter configuration space, if the adapter is owned by the invoking partition. Dynamic table 404 is used to copy those call addresses which should be available to the requesting computer, depending on the adapter type. In this example, the requesting computer is given access to all H_calls (and hence all partitions), so the dynamic table is populated with all the H_calls. FIG. 5 shows a case where a requesting computer is not given access to all H_calls. Based on the requesting computer's adapter type (or other detectable hardware attribute), dynamic table 504 is populated with only certain ones 506 , 510 of H_calls from table 502 . Calls 508 are replaced with addresses that will return an error. Hence, the mechanism of the present invention limits the number of external interfaces without limiting needed capability to communicate for the various types of partitions and adapters. FIG. 7 shows a situation where the some of the partitions share hypervisor calls. In this example, Hypervisor 702 includes Hypervisor I/F 704 that makes available calls 706 , 708 , 710 for accessing various partitions 712 , 714 , 716 . In this example, all partitions are exposed to external interfaces. FIG. 8 shows an illustrative embodiment the present invention implemented using restrictions to partitions based on the partition type instead of the adapter type. In this example, hypervisor 802 includes hypervisor I/F 804 and the various shared and partition specific calls 806 , 808 , 810 . In this example, H_calls 810 are not available to a requesting computer, and therefore only partitions 812 , 814 can be accessed by a requesting computer. FIG. 9 complements FIG. 8 in that it shows the opposite case, namely access to only calls for partition 910 are accessible to an external computer or request. It is noted that in both FIGS. 8 and 9 that shared calls 906 are accessible, while the unnecessary partitions are hidden from an external computer. FIG. 10 shows this situation in terms of static table 1002 and dynamic table 1004 . Once the hypervisor discovers the type of operating system and partition to be communicated with, the relevant addresses for communicating with that partition are used to populate table 1004 , giving access to those addresses for making H_calls to the relevant partition 910 . The remaining cells of table 1004 are populated by addresses that will return an error. FIGS. 6 and 11 depict flowcharts for implementing embodiments of the present invention. FIG. 6 shows the embodiment wherein the dynamic table is populated with addresses based on the type of hardware adapter used to communicate with the hypervisor and partitions. This process is preferably implemented in hypervisor 302 in conjunction with data processing system 100 . The process begins with a search for specialized hardware adapters of the requesting computer (step 600 ). A determination is made as to whether the adapter is identified (step 602 ). If it is, then the appropriate calls for that adapter are copied from the static table to the dynamic table (step 604 ). If there are more adapters (step 606 ), then the process repeats. If the adapter is not identified, a routine to return an error is copied into the dynamic table. FIG. 11 starts with a search to see if the requesting computer is requesting access to a particular operating system or partition type (step 1100 ). In preferred embodiments, this is done by reading the system's particular VPD (vital product data) type. If the partition is identified (step 1102 ) then the appropriate calls for that partition are copied into the dynamic table (step 1104 ). If more partitions are discovered (step 1106 ), then the process repeats. If the partition is not identified, then a routine to return an error is copied into the dynamic table (step 1108 ). This process is preferably implemented in hypervisor 302 in conjunction with data processing system 100 . In the illustrative embodiments, the requesting computer can make calls by the normal hypervisor interface. The hypervisor interface indexes the call to the dynamic table, for example, using a token, to identify the proper location in the dynamic table to find the address. In other illustrative embodiments, the hypervisor only exposes the initialization call on startup. The initializing partition then makes the call to initialize, for example, the adapter, and the initialization H_call would expose all other relevant interfaces. This could be used in systems where the adapters may be installed but not used frequently. Then only the initialized H_call is exposed until the adapter is needed. The present invention provides advantage over other systems in several ways, including low overhead to monitor the interfaces, and hiding unheeded H_calls from external interfaces, thereby limiting the avenues for outside attacks. Further, rather than adding code to each and every call, the present invention allows for a specific exit point which reduces overhead. The innovations herein are much safer in terms of exposed KLOCs, maintenance, and reduce the execution time in processing. It is important to note that while the present invention has been described in the context of a fully functioning data processing system, those of ordinary skill in the art will appreciate that the processes of the present invention are capable of being distributed in the form of a computer readable medium of instructions and a variety of forms and that the present invention applies equally regardless of the particular type of signal bearing media actually used to carry out the distribution. Examples of computer readable media include recordable-type media, such as a floppy disk, a hard disk drive, a RAM, CD-ROMs, DVD-ROMs, and transmission-type media, such as digital and analog communications links, wired or wireless communications links using transmission forms, such as, for example, radio frequency and light wave transmissions. The computer readable media may take the form of coded formats that are decoded for actual use in a particular data processing system. The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.
A system and method to reduce external access to hypervisor interfaces in a computer system, thereby reducing the possibility of attacks. In a preferred embodiment, addresses for calls are used to fill a table, where the addresses are specifically selected for a requesting computer. For example, in one embodiment, a routine searches for the adapter type of a requesting computer and populates the table with calls specific to that type of adapter. Other types of calls are not put in the table. Instead, those calls are replaced by routines that will return an error. In other embodiments, the operating system type is used to determine what addresses are used to populate the table. These and other embodiments are explained more fully below.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "BACKGROUND OF THE INVENTION 1.", "Technical Field The present invention relates generally to security in a computer system, and particularly to limiting vulnerability to attacks on a partitioned computer system.", "Description of Related Art As security issues become a greater concern, the IT industry is undergoing a rapid transformation to enhance security in all aspects.", "Currently a number of nations have embraced the Common Criteria Evaluation methodologies, a rigorous and expensive methodology used to evaluate the security assurance level that a IT system possesses.", "This methodology encompasses all aspects of IT product development, ranging from building security where development activities take place, CM systems, development activities, and up to and including secure delivery of the product to prevent tampering.", "Currently the US government requires this evaluation to be completed for all IT equipment used in national security, critical infrastructure and Homeland Defense systems.", "Additionally the financial and healthcare industries are embracing these evaluations as part of the proposed requirements for their systems to be purchased.", "Current hypervisor designs have exposed external interfaces to provide general services (non-hardware specific) to the operating systems loaded such as interrupt management, Page Table Entry (PTE) management, Translation Control Entry (TCE) management as well as specialized interfaces to handle specialized hardware resources such as Federation or InfiniBand (IB) adapters.", "FIG. 3 shows a known system for platform firmware, such as Hypervisor.", "Hypervisor is available from International Business Machines Corporation.", "Hypervisor 302 includes Hypervisor I/F 304 which allows access to Hypervisor calls (H_calls) for various partitions 310 , 312 , 314 .", "Depending on the particular adapter hardware, some calls are hardware dependent 308 while some calls are non-hardware dependent 306 .", "All types of partitions are presented with both types of interface.", "Currently International Business Machines is introducing the first of a converged hypervisor design that supports multiple different simultaneous operating systems on a single platform.", "In this hypervisor design, multiple operating systems are allowed to access all hypervisor calls, H_CALLS, through hypervisor interface.", "In the current design there are more than 350 hypervisor calls, some dedicated to RPA partitions (of the RS/6000 platform architecture), some dedicated to OS/400 partitions and some shared.", "In the current product plans it is well understood that the majority of systems will only support RPA partitions because the industry is moving away from proprietary OSs like OS/400.", "The majority of delivered systems will only use AIX or Linux partitions and therefore the exposed hypervisor interfaces specific to OS/400 partitions represent vulnerable attack points that have no product value in RPA only systems.", "Conversely the customers needing OS/400 partitions most likely will not use RPA partitions at the same time, those customers using both RPA and non-RPA partitions on the same system is only a very small percentage of the overall market.", "In the current systems only a few platforms support the Federation adapter and plans for the InfiniBand adapter are for a small percentage of system, however all platforms have hypervisor calls for these adapters exposed.", "In the p6xx series, from the p625, p630, p640, p650, p655, p670, and p690, only the p670 and p690 provide hardware support for the Federation adapters and only a very small percentage of p670 and p690 systems are shipped with the Federation adapters.", "These interfaces represent unused unnecessary attack points when the adapters are not installed.", "An analysis of the security of a system shows that the exposed external interfaces are the attack points for external threats, increase the number of interfaces and vulnerability increases.", "Additionally analysis has shown and is well documented in many publications that there is approximately one security flaw in every KLOC (thousand lines of code) of delivered code.", "According to an excerpt taken from the Trusted Computing Group's Backgrounder of May 2003: A critical problem being addressed by creation and use of these specifications is the increasing threat of software attack due to a combination of increasingly sophisticated and automated attack tools, the rapid increase in the number of vulnerabilities being discovered, and the increasing mobility of users.", "The large number of vulnerabilities is due, in part, to the incredible complexity of modern systems.", "For example, a typical Unix or Windows system, including major applications, represents on the order of 100 million lines of code.", "Recent studies have shown that typical product level software has roughly one security related bug per thousand of lines of source code.", "Thus, a typical system will potentially have one hundred thousand security bugs.", "Current plans for the POWER5 LPAR platform are to undergo a complete security evaluation to meet the EAL4+ Common Criteria requirements.", "In review of the previous platform evaluation, two critical areas are interpartition protection and access control between partitions.", "The exposure of additional unused interfaces represents a significant increase in vulnerability during the use of these systems as well as an increase in the testing efforts.", "Current solutions to this problem is to include code in each and every H_CALL (hypervisor call) dedicated to the specialized hardware that looks for adapter presence and/or checks to see if the adapter has been initialized.", "This requires code in many routines as opposed to having a single immediate exit point.", "Therefore, it would be advantageous to have an improved method and apparatus for enhancing access security to hypervisor calls by partitioned systems.", "SUMMARY OF THE INVENTION The present invention provides a method, apparatus, and computer instructions to reduce external access to partitions in a computer system, thereby reducing the possibility of attacks.", "In a preferred embodiment, addresses for calls are used to fill a table, where the addresses are specifically selected for a requesting computer.", "For example, in one embodiment, a routine searches for the adapter type of a requesting computer and populates the table with calls specific to that type of adapter.", "Other types of calls are not put in the table.", "Instead, those calls are replaced by routines that will return an error.", "In other embodiments, the operating system type is used to determine what addresses are used to populate the table.", "These and other embodiments are explained more fully below.", "BRIEF DESCRIPTION OF THE DRAWINGS The novel features believed characteristic of the invention are set forth in the appended claims.", "The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: FIG. 1 is a block diagram of a data processing system in which the present invention may be implemented;", "FIG. 2 is a block diagram of an exemplary logical partitioned platform in which the present invention may be implemented;", "FIG. 3 shows a known partitioned data processing system with hypervisor where each partition can be accessed by each type of call.", "FIG. 4 shows a static table and a dynamic table for holding hypervisor call addresses consistent with a preferred embodiment of the present invention.", "FIG. 5 shows a static table and a dynamic table where some of the dynamic table entries are filled with routines that return an error, consistent with a preferred embodiment of the present invention.", "FIG. 6 shows a flowchart with process steps for implementing a preferred embodiment of the present invention.", "FIG. 7 shows a hypervisor and partitions for a computer system where all partitions are visible.", "FIG. 8 shows a hypervisor and partitions where one partition is hidden from external calling, consistent with a preferred embodiment of the present invention.", "FIG. 9 shows a hypervisor and partitions where two partitions are hidden from external calling, consistent with a preferred embodiment of the present invention.", "FIG. 10 shows static and dynamic tables consistent with implementing a preferred embodiment of the present invention.", "FIG. 11 shows a flowchart with process steps for implementing a preferred embodiment of the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now to the figures, and in particular with reference to FIG. 1 , a block diagram of a data processing system in which the present invention may be implemented is depicted.", "Data processing system 100 may be a symmetric multiprocessor (SMP) system including a plurality of processors 101 , 102 , 103 , and 104 connected to system bus 106 .", "For example, data processing system 100 may be an IBM eServer, a product of International Business Machines Corporation in Armonk, N.Y., implemented as a server within a network.", "Alternatively, a single processor system may be employed.", "Also connected to system bus 106 is memory controller/cache 108 , which provides an interface to a plurality of local memories 160 - 163 .", "I/O bus bridge 110 is connected to system bus 106 and provides an interface to I/O bus 112 .", "Memory controller/cache 108 and I/O bus bridge 110 may be integrated as depicted.", "Data processing system 100 is a logical partitioned (LPAR) data processing system.", "Thus, data processing system 100 may have multiple heterogeneous operating systems (or multiple instances of a single operating system) running simultaneously.", "Each of these multiple operating systems may have any number of software programs executing within it.", "Data processing system 100 is logically partitioned such that different PCI I/O adapters 120 - 121 , 128 - 129 , and 136 , graphics adapter 148 , and hard disk adapter 149 may be assigned to different logical partitions.", "In this case, graphics adapter 148 provides a connection for a display device (not shown), while hard disk adapter 149 provides a connection to control hard disk 150 .", "Thus, for example, suppose data processing system 100 is divided into three logical partitions, P 1 , P 2 , and P 3 .", "Each of PCI I/O adapters 120 - 121 , 128 - 129 , 136 , graphics adapter 148 , hard disk adapter 149 , each of host processors 101 - 104 , and memory from local memories 160 - 163 is assigned to each of the three partitions.", "In these examples, memories 160 - 163 may take the form of dual in-line memory modules (DIMMs).", "DIMMs are not normally assigned on a per DIMM basis to partitions.", "Instead, a partition will get a portion of the overall memory seen by the platform.", "For example, processor 101 , some portion of memory from local memories 160 - 163 , and I/O adapters 120 , 128 , and 129 may be assigned to logical partition P 1 ;", "processors 102 - 103 , some portion of memory from local memories 160 - 163 , and PCI I/O adapters 121 and 136 may be assigned to partition P 2 ;", "and processor 104 , some portion of memory from local memories 160 - 163 , graphics adapter 148 and hard disk adapter 149 may be assigned to logical partition P 3 .", "Each operating system executing within data processing system 100 is assigned to a different logical partition.", "Thus, each operating system executing within data processing system 100 may access only those I/O units that are within its logical partition.", "Thus, for example, one instance of the Advanced Interactive Executive (AIX) operating system may be executing within partition P 1 , a second instance (image) of the AIX operating system may be executing within partition P 2 , and a Linux or OS/400 operating system may be operating within logical partition P 3 .", "Peripheral component interconnect (PCI) host bridge 114 connected to I/O bus 112 provides an interface to PCI local bus 115 .", "A number of PCI input/output adapters 120 - 121 may be connected to PCI bus 115 through PCI-to-PCI bridge 116 , PCI bus 118 , PCI bus 119 , I/O slot 170 , and I/O slot 171 .", "PCI-to-PCI bridge 116 provides an interface to PCI bus 118 and PCI bus 119 .", "PCI I/O adapters 120 and 121 are placed into I/O slots 170 and 171 , respectively.", "Typical PCI bus implementations will support between four and eight I/O adapters (i.e. expansion slots for add-in connectors).", "Each PCI I/O adapter 120 - 121 provides an interface between data processing system 100 and input/output devices such as, for example, other network computers, which are clients to data processing system 100 .", "An additional PCI host bridge 122 provides an interface for an additional PCI bus 123 .", "PCI bus 123 is connected to a plurality of PCI I/O adapters 128 - 129 .", "PCI I/O adapters 128 - 129 may be connected to PCI bus 123 through PCI-to-PCI bridge 124 , PCI bus 126 , PCI bus 127 , I/O slot 172 , and I/O slot 173 .", "PCI-to-PCI bridge 124 provides an interface to PCI bus 126 and PCI bus 127 .", "PCI I/O adapters 128 and 129 are placed into I/O slots 172 and 173 , respectively.", "In this manner, additional I/O devices, such as, for example, modems or network adapters may be supported through each of PCI I/O adapters 128 129 .", "In this manner, data processing system 100 allows connections to multiple network computers.", "A memory mapped graphics adapter 148 inserted into I/O slot 174 may be connected to I/O bus 112 through PCI bus 144 , PCI-to-PCI bridge 142 , PCI bus 141 and PCI host bridge 140 .", "Hard disk adapter 149 may be placed into I/O slot 175 , which is connected to PCI bus 145 .", "In turn, this bus is connected to PCI-to-PCI bridge 142 , which is connected to PCI host bridge 140 by PCI bus 141 .", "A PCI host bridge 130 provides an interface for a PCI bus 131 to connect to I/O bus 112 .", "PCI I/O adapter 136 is connected to I/O slot 176 , which is connected to PCI-to-PCI bridge 132 by PCI bus 133 .", "PCI-to-PCI bridge 132 is connected to PCI bus 131 .", "This PCI bus also connects PCI host bridge 130 to the service processor mailbox interface and ISA bus access pass-through logic 194 and PCI-to-PCI bridge 132 .", "Service processor mailbox interface and ISA bus access pass-through logic 194 forwards PCI accesses destined to the PCI/ISA bridge 193 .", "NVRAM storage 192 is connected to the ISA bus 196 .", "Service processor 135 is coupled to service processor mailbox interface and ISA bus access pass-through logic 194 through its local PCI bus 195 .", "Service processor 135 is also connected to processors 101 - 104 via a plurality of JTAG/I 2 C busses 134 .", "JTAG/I 2 C busses 134 are a combination of JTAG/scan busses (see IEEE 1149.1) and Phillips I 2 C busses.", "However, alternatively, JTAG/I 2 C busses 134 may be replaced by only Phillips I 2 C busses or only JTAG/scan busses.", "All SP-ATTN signals of the host processors 101 , 102 , 103 , and 104 are connected together to an interrupt input signal of the service processor.", "The service processor 135 has its own local memory 191 , and has access to the hardware OP-panel 190 .", "When data processing system 100 is initially powered up, service processor 135 uses the JTAG/I 2 C busses 134 to interrogate the system (host) processors 101 - 104 , memory controller/cache 108 , and I/O bridge 110 .", "At completion of this step, service processor 135 has an inventory and topology understanding of data processing system 100 .", "Service processor 135 also executes Built-In-Self-Tests (BISTs), Basic Assurance Tests (BATs), and memory tests on all elements found by interrogating the host processors 101 - 104 , memory controller/cache 108 , and I/O bridge 110 .", "Any error information for failures detected during the BISTS, BATs, and memory tests are gathered and reported by service processor 135 .", "If a meaningful/valid configuration of system resources is still possible after taking out the elements found to be faulty during the BISTs, BATs, and memory tests, then data processing system 100 is allowed to proceed to load executable code into local (host) memories 160 - 163 .", "Service processor 135 then releases host processors 101 - 104 for execution of the code loaded into local memory 160 - 163 .", "While host processors 101 - 104 are executing code from respective operating systems within data processing system 100 , service processor 135 enters a mode of monitoring and reporting errors.", "The type of items monitored by service processor 135 include, for example, the cooling fan speed and operation, thermal sensors, power supply regulators, and recoverable and non-recoverable errors reported by processors 101 - 104 , local memories 160 - 163 , and I/O bridge 110 .", "Service processor 135 is responsible for saving and reporting error information related to all the monitored items in data processing system 100 .", "Service processor 135 also takes action based on the type of errors and defined thresholds.", "For example, service processor 135 may take note of excessive recoverable errors on a processor's cache memory and decide that this is predictive of a hard failure.", "Based on this determination, service processor 135 may mark that resource for deconfiguration during the current running session and future Initial Program Loads (IPLs).", "IPLs are also sometimes referred to as a “boot”", "or “bootstrap.”", "Data processing system 100 may be implemented using various commercially available computer systems.", "For example, data processing system 100 may be implemented using IBM eServer iSeries Model 840 system available from International Business Machines Corporation.", "Such a system may support logical partitioning using an OS/400 operating system, which is also available from International Business Machines Corporation.", "Those of ordinary skill in the art will appreciate that the hardware depicted in FIG. 1 may vary.", "For example, other peripheral devices, such as optical disk drives and the like, also may be used in addition to or in place of the hardware depicted.", "The depicted example is not meant to imply architectural limitations with respect to the present invention.", "With reference now to FIG. 2 , a block diagram of an exemplary logical partitioned platform is depicted in which the present invention may be implemented.", "The hardware in logical partitioned platform 200 may be implemented as, for example, data processing system 100 in FIG. 1 .", "Logical partitioned platform 200 includes partitioned hardware 230 , operating systems 202 , 204 , 206 , 208 , and partition management firmware 210 .", "Operating systems 202 , 204 , 206 , and 208 may be multiple copies of a single operating system or multiple heterogeneous operating systems simultaneously run on logical partitioned platform 200 .", "These operating systems may be implemented using OS/400, which are designed to interface with a partition management firmware, such as Hypervisor.", "OS/400 is used only as an example in these illustrative embodiments.", "Of course, other types of operating systems, such as AIX and linux, may be used depending on the particular implementation.", "Operating systems 202 , 204 , 206 , and 208 are located in partitions 203 , 205 , 207 , and 209 .", "Hypervisor software is an example of software that may be used to implement platform (in this example, partition management) firmware 210 and is available from International Business Machines Corporation.", "Firmware is “software”", "stored in a memory chip that holds its content without electrical power, such as, for example, read-only memory (ROM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), and nonvolatile random access memory (nonvolatile RAM).", "Additionally, these partitions also include partition firmware 211 , 213 , 215 , and 217 .", "Partition firmware 211 , 213 , 215 , and 217 may be implemented using initial boot strap code, IEEE-1275 Standard Open Firmware, and runtime abstraction software (RTAS), which is available from International Business Machines Corporation.", "When partitions 203 , 205 , 207 , and 209 are instantiated, a copy of boot strap code is loaded onto partitions 203 , 205 , 207 , and 209 by platform firmware 210 .", "Thereafter, control is transferred to the boot strap code with the boot strap code then loading the open firmware and RTAS.", "The processors associated or assigned to the partitions are then dispatched to the partition's memory to execute the partition firmware.", "Partitioned hardware 230 includes a plurality of processors 232 - 238 , a plurality of system memory units 240 - 246 , a plurality of input/output (I/O) adapters 248 - 262 , and a storage unit 270 .", "Each of the processors 232 - 238 , memory units 240 - 246 , NVRAM storage 298 , and I/O adapters 248 - 262 may be assigned to one of multiple partitions within logical partitioned platform 200 , each of which corresponds to one of operating systems 202 , 204 , 206 , and 208 .", "Platform firmware 210 performs a number of functions and services for partitions 203 , 205 , 207 , and 209 to create and enforce the partitioning of logical partitioned platform 200 .", "Platform firmware 210 is a firmware implemented virtual machine identical to the underlying hardware.", "Thus, platform firmware 210 allows the simultaneous execution of independent OS images 202 , 204 , 206 , and 208 by virtualizing all the hardware resources of logical partitioned platform 200 .", "Service processor 290 may be used to provide various services, such as processing of platform errors in the partitions.", "These services also may act as a service agent to report errors back to a vendor, such as International Business Machines Corporation.", "Operations of the different partitions may be controlled through a hardware management console, such as hardware management console 280 .", "Hardware management console 280 is a separate data processing system from which a system administrator may perform various functions including reallocation of resources to different partitions.", "FIG. 4 shows a set of tables consistent with implementing a preferred embodiment of the present invention.", "In a first preferred embodiment, the present invention dynamically restricts the number of external hypervisor interfaces presented based on the presence of specialized hardware adapters installed in the requesting computer.", "By restricting access by an external computer to certain hypervisor calls, access to certain partitions behind the hypervisor is restricted.", "In this example, static table 402 includes all H_call addresses.", "H_calls, or hypervisor calls, are services used by partition firmware.", "As RTAS instantiation (run time abstraction services) happens, all RTAS calls in SMP mode are routed to the hypervisor using H_calls.", "These calls are not exposed to the operating system and are subject to change at the convenience of the hypervisor and/or partition firmware.", "Examples of H_calls include h_get_xive, which is called by pSeries firmware to get the contents of the xive interrupt control register;", "and h_pci_config_read, which reads the PCI adapter configuration space, if the adapter is owned by the invoking partition.", "Dynamic table 404 is used to copy those call addresses which should be available to the requesting computer, depending on the adapter type.", "In this example, the requesting computer is given access to all H_calls (and hence all partitions), so the dynamic table is populated with all the H_calls.", "FIG. 5 shows a case where a requesting computer is not given access to all H_calls.", "Based on the requesting computer's adapter type (or other detectable hardware attribute), dynamic table 504 is populated with only certain ones 506 , 510 of H_calls from table 502 .", "Calls 508 are replaced with addresses that will return an error.", "Hence, the mechanism of the present invention limits the number of external interfaces without limiting needed capability to communicate for the various types of partitions and adapters.", "FIG. 7 shows a situation where the some of the partitions share hypervisor calls.", "In this example, Hypervisor 702 includes Hypervisor I/F 704 that makes available calls 706 , 708 , 710 for accessing various partitions 712 , 714 , 716 .", "In this example, all partitions are exposed to external interfaces.", "FIG. 8 shows an illustrative embodiment the present invention implemented using restrictions to partitions based on the partition type instead of the adapter type.", "In this example, hypervisor 802 includes hypervisor I/F 804 and the various shared and partition specific calls 806 , 808 , 810 .", "In this example, H_calls 810 are not available to a requesting computer, and therefore only partitions 812 , 814 can be accessed by a requesting computer.", "FIG. 9 complements FIG. 8 in that it shows the opposite case, namely access to only calls for partition 910 are accessible to an external computer or request.", "It is noted that in both FIGS. 8 and 9 that shared calls 906 are accessible, while the unnecessary partitions are hidden from an external computer.", "FIG. 10 shows this situation in terms of static table 1002 and dynamic table 1004 .", "Once the hypervisor discovers the type of operating system and partition to be communicated with, the relevant addresses for communicating with that partition are used to populate table 1004 , giving access to those addresses for making H_calls to the relevant partition 910 .", "The remaining cells of table 1004 are populated by addresses that will return an error.", "FIGS. 6 and 11 depict flowcharts for implementing embodiments of the present invention.", "FIG. 6 shows the embodiment wherein the dynamic table is populated with addresses based on the type of hardware adapter used to communicate with the hypervisor and partitions.", "This process is preferably implemented in hypervisor 302 in conjunction with data processing system 100 .", "The process begins with a search for specialized hardware adapters of the requesting computer (step 600 ).", "A determination is made as to whether the adapter is identified (step 602 ).", "If it is, then the appropriate calls for that adapter are copied from the static table to the dynamic table (step 604 ).", "If there are more adapters (step 606 ), then the process repeats.", "If the adapter is not identified, a routine to return an error is copied into the dynamic table.", "FIG. 11 starts with a search to see if the requesting computer is requesting access to a particular operating system or partition type (step 1100 ).", "In preferred embodiments, this is done by reading the system's particular VPD (vital product data) type.", "If the partition is identified (step 1102 ) then the appropriate calls for that partition are copied into the dynamic table (step 1104 ).", "If more partitions are discovered (step 1106 ), then the process repeats.", "If the partition is not identified, then a routine to return an error is copied into the dynamic table (step 1108 ).", "This process is preferably implemented in hypervisor 302 in conjunction with data processing system 100 .", "In the illustrative embodiments, the requesting computer can make calls by the normal hypervisor interface.", "The hypervisor interface indexes the call to the dynamic table, for example, using a token, to identify the proper location in the dynamic table to find the address.", "In other illustrative embodiments, the hypervisor only exposes the initialization call on startup.", "The initializing partition then makes the call to initialize, for example, the adapter, and the initialization H_call would expose all other relevant interfaces.", "This could be used in systems where the adapters may be installed but not used frequently.", "Then only the initialized H_call is exposed until the adapter is needed.", "The present invention provides advantage over other systems in several ways, including low overhead to monitor the interfaces, and hiding unheeded H_calls from external interfaces, thereby limiting the avenues for outside attacks.", "Further, rather than adding code to each and every call, the present invention allows for a specific exit point which reduces overhead.", "The innovations herein are much safer in terms of exposed KLOCs, maintenance, and reduce the execution time in processing.", "It is important to note that while the present invention has been described in the context of a fully functioning data processing system, those of ordinary skill in the art will appreciate that the processes of the present invention are capable of being distributed in the form of a computer readable medium of instructions and a variety of forms and that the present invention applies equally regardless of the particular type of signal bearing media actually used to carry out the distribution.", "Examples of computer readable media include recordable-type media, such as a floppy disk, a hard disk drive, a RAM, CD-ROMs, DVD-ROMs, and transmission-type media, such as digital and analog communications links, wired or wireless communications links using transmission forms, such as, for example, radio frequency and light wave transmissions.", "The computer readable media may take the form of coded formats that are decoded for actual use in a particular data processing system.", "The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed.", "Many modifications and variations will be apparent to those of ordinary skill in the art.", "The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This is a continuation of U.S. application Ser. No. 10/521,383, filed Jan. 10, 2005, which is a national stage filing under 35 U.S.C. § 371 of International Application No. PCT/GB03/003205, filed Jul. 25, 2003, which is an international application of and claims priority to United Kingdom Application No. GB0217273.2, filed Jul. 25, 2002, all of which are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of Invention The present invention relates to a laser system and a method of operating a laser system. [0003] 2. Discussion of Related Art [0004] Medical lasers are used in certain medical procedures to administer thermal or other energy to a patient with beneficial effects. For example, energy can be used to detect or treat a tumour or a region of the body, or to destroy or denature diseased or malfunctioning body tissue. U.S. Pat. No. 6,095,149 describes, for example, the treatment of invertebral disc abnormalities with thermal energy. Other forms of medical treatment utilise laser energy such as endovenous laser treatment (EVLT) wherein laser energy is delivered to the inner wall of a vein. [0005] A known laser system comprises a laser device for emitting laser radiation and an optical fibre for directing the laser radiation to the required location. [0006] The laser system may be used for a variety of different purposes and optical fibres for use with the laser device may be provided with a standard connector for attachment to the laser device. [0007] Optical fibres used in conjunction with a laser device may, in certain circumstances, have a relatively limited lifetime. For example, the lifetime of an optical fibre may be limited due to hygiene requirements in medical applications. An optical fibre may additionally/alternatively also have a limited lifetime before it becomes susceptible to damage. [0008] A laser device may have been initially calibrated with a new optical fibre to deliver a certain intensity laser beam. However, if the optical fibre is reused a number of times then the presence of dirt etc. on the optical fibre may result in a lower than desired intensity laser beam being delivered which, for example in medical applications, could render the intended medical treatment ineffective. [0009] In some applications optical fibres may only be intended for single use and should be disposed of thereafterwards for health and safety reasons. EP 0473987 discloses a method and apparatus for optoelectrical recognition of disposable medical applicators connected to a laser. SUMMARY OF INVENTION [0010] According to an aspect of the present invention there is provided a laser system comprising: a laser device for emitting laser radiation; and a delivery device adapted to connect, in use, to the laser device for delivering the laser radiation; wherein, in use, the laser device receives information from the delivery device. [0011] An advantage of the preferred embodiment is that an operator can be certain that a correct, safe and effective optical fibre or other delivery device has been attached to the laser device and that the optical fibre or other delivery device is suitable for the intended use. This may be particularly important in medical applications. [0012] The delivery device is preferably an optical fibre and the laser device preferably includes a detector for detecting the connection of the delivery device. The laser device preferably interrogates the delivery device after detecting the connection. The laser device preferably interrogates the delivery device or optical fibre in a contactless manner. [0013] Information is preferably encoded, embedded within or otherwise stored with the delivery device and may indicate the type, usage, state, age, intended use and/or function of the delivery device. [0014] According to a preferred embodiment the delivery device comprises an AC or RF identification tag or transponder. The identification tag may be either a read only device or in an alternative embodiment a read/write device. [0015] The laser device preferably comprises an AC or RF identification reader for reading the AC or RF identification tag or transponder. In use, the delivery device preferably transmits or returns a signal to the AC or RF identification reader. [0016] According to a preferred embodiment the delivery device receives, in use, a power pulse. The delivery device preferably receives AC or RF energy, stores the energy and then transmits back to the laser device data or information using the stored energy. [0017] According to a less preferred embodiment the delivery device may comprise a barcode and the laser device may comprise a barcode reader. [0018] According to another less preferred embodiment the delivery device may comprise a colour identification tag and the laser device may identify the colour identification tag. [0019] The laser device preferably comprises a SMA-905 connector for receiving an optical fibre. [0020] According to a preferred embodiment in a mode of operation the laser device prevents operation with the delivery device upon receiving information from the delivery device. In a mode of operation the laser device may prevent operation with the delivery device if the laser device does not receive any information from the delivery device. The laser device may also prevent operation if a conventional delivery device known per se, for example a known delivery device which does not transmit information to the laser device, is connected to the laser device. [0021] The laser device may in a mode of operation prevent operation with the delivery device if the laser device receives information from the delivery device and wherein the information indicates a predetermined parameter is unsuitable or has been exceeded. The parameter may, for example, indicate the usage, sterility, type and/or expiry date of the delivery device. If the laser device does disable or limit operation with a delivery device then in a mode of operation the laser device may be enabled and/or disabled remotely, for example via a telephone link, a serial interface, via the internet or other means. [0022] The laser device may be provided with a visual display adapted to provide the user with information received from the delivery device. [0023] According to a preferred embodiment in a mode of operation the laser device receives information from the delivery device and sets the power and/or pulse width and/or interval between pulses and/or duration of laser radiation to be transmitted to the delivery device and hence delivered by the delivery device. Advantageously, this enables the laser device to be safely operated without requiring a skilled technician to control the operation of the laser device. [0024] According to another aspect of the present invention there is provided an optical fibre assembly comprising an AC or RF identification tag or transponder. [0025] According to another aspect of the present invention there is provided a laser device comprising a reader for reading an AC or RF identification tag or transponder on an optical fibre assembly. [0026] According to another aspect of the present invention there is provided a laser system comprising: an optical fibre assembly comprising an AC or RF identification tag or transponder; and a laser device comprising a reader for reading the AC or RF identification tag or transponder. [0027] According to another aspect of the present invention there is provided an optical fibre comprising a barcode. [0028] According to another aspect of the present invention there is provided a laser device comprising a barcode reader for reading a barcode on an optical fibre. [0029] According to another aspect of the present invention there is provided a laser system comprising: an optical fibre comprising a barcode; and a laser device comprising a barcode reader for reading the barcode. [0030] According to another aspect of the present invention there is provided a laser system comprising: a laser device for emitting laser radiation; and a delivery device adapted to connect, in use, to the laser device for delivering the laser radiation, the delivery device comprising a read/write device for storing information; wherein, in use, the laser device updates the information on the read/write device. [0031] Preferably, the laser system in accordance with any aspect of the present invention comprises a medical laser system. [0032] According to another aspect of the present invention there is provided a medical laser system comprising: a laser device for emitting laser radiation; and a delivery device adapted to connect, in use, to the laser device for delivering the laser radiation; wherein, in use, the laser device receives information from the delivery device. [0033] According to another aspect of the present invention there is provided a method of operating a laser system comprising the steps of: providing a laser device; and connecting a delivery device to the laser device; wherein said laser device receives information from the delivery device. [0034] According to another aspect of the present invention there is provided a method of operating a laser system comprising providing a laser device and a delivery device wherein the laser device interrogates the delivery device. Preferably, the laser device detects the attachment of the delivery device prior to interrogating the delivery device. [0035] According to another aspect of the present invention there is provided a method of operating a laser system comprising the steps of: providing a laser device; and attaching a delivery device to the laser device; wherein the laser device detects the attachment of the delivery device and interrogates the delivery device upon detection of the attachment of the delivery device. [0036] Preferably, the method of any aspect of the present invention further comprises the laser device enabling operation of the laser system upon receiving information from the delivery device. [0037] The laser device preferably receives information from the delivery device and displays the information for the user. The information received by the laser device from the delivery device may preferably indicate the usage, sterility, type or expiry date of the delivery device. [0038] A method of operating a laser system in accordance with any aspect of the present invention may preferably further include in a mode of operation the laser device being enabled and/or disabled remotely. [0039] According to another aspect of the present invention there is provided a method of operating a laser system comprising the steps of: providing a laser device; attaching a delivery device to a laser device; and transmitting a power pulse to the delivery device; wherein the delivery device receives the pulse, stores the pulse and transmits data to the laser device using the pulse. The pulse is preferably a pulse of AC or RF energy. [0040] Preferably, the laser device may receive information from the delivery device and configure the operation of the laser device. BRIEF DESCRIPTION OF DRAWINGS [0041] Various embodiments of the present invention will now be described, by way of example only, and with reference to the accompanying drawing in which: [0042] FIG. 1 shows a laser system according to the preferred embodiment. DETAILED DESCRIPTION [0043] A preferred embodiment of the present invention will now be described with reference to FIG. 1 . A laser system 10 is shown comprising a laser device 1 for emitting laser radiation and a delivery device 2 adapted and arranged to be connected to the laser device 1 . [0044] According to the preferred embodiment, the laser device 1 is an 810 nm diode laser manufactured by DIOMED, Ltd., United Kingdom and the delivery device 2 is an optical fibre. The delivery device 2 may be connected to the laser device 1 using any suitable connector/fibre terminator such as a standard sub-miniature A (SMA) connector. Alternatively, according to a less preferred embodiment, the delivery device may comprise a mirror based delivery system. [0045] The delivery device 2 is preferably fully compatible with existing systems. For example, the delivery device 2 is preferably suitable for interfacing with various accessories such as EVLT sheathes, spot handpieces and ENT accessories. [0046] Information from the delivery device 2 is received by the laser device 1 . Receiving information from the delivery device 2 preferably does not require any additional connection between the laser device 1 and the delivery device 2 , and a contactless method of receiving information from the delivery device 2 is particularly preferred. According to the preferred embodiment an AC or RF tag or transponder 3 is embedded within or provided on the delivery device 2 . The data or information received by the laser device 1 from the delivery device 2 is preferably pre-assigned to the delivery device 2 during manufacture. [0047] A reader for receiving information from the delivery device 2 is preferably provided within the laser device 1 . The reader may collect data or information which is then transferred through standard interfaces to the control of the laser device 1 . [0048] The reader provided within the laser device 1 may read an RF or AC identification tag or transponder 3 provided on the delivery device 2 . The reader preferably comprises an antenna, a transceiver and a processor. The RF or AC identification tag or transponder 3 preferably comprises an antenna and an integrated circuit or silicon chip. The RF or AC identification tag or transponder 3 may be encapsulated in glass or plastic which may then be attached to the delivery device 2 . [0049] In an embodiment the identification tag or transponder 3 may be a passive system which remains in an OFF state until activated by a signal from the reader. Preferably, the identification tag or transponder 3 is of the type which does not require an internal power source such as a battery. [0050] According to a preferred embodiment the AC or RF identification tag or transponder 3 is embedded within a moulding attached to the delivery device 2 e.g. optical fibre. The moulding is preferably attached to the delivery device 2 or optical fibre approximately 5 cm from a connector which is used to connect the optical fibre 2 to the laser device 1 . Thus, when the delivery device 2 or optical fibre is attached to the laser device 1 the identification tag or transponder 3 remains external to the laser device 1 . [0051] According to other embodiments the delivery device 2 may comprise a barcode or colour identification tag which is preferably located within the housing of the laser device 1 when the delivery device 2 is connected to the laser device 1 . [0052] The delivery device 2 is preferably able to withstand Ethylene Oxide sterilisation and accordingly an encapsulated AC or RF identification tag 3 is particularly preferred. [0053] The identification tag 3 may comprise a Read Only or a Read/Write device. The data held on the identification tag 3 may be pre-programmed onto the delivery device 2 during manufacture. If a Read/Write device is used the laser device 1 may update the information on the identification tag upon connection and may for example record the date and usage of the delivery device 2 . [0054] The information received by the laser device 1 is preferably displayed for the user on a display 4 which may be integral with the laser device 1 . The information may be displayed, for example, as a series of messages and/or warning (s) based on the data exchanged. [0055] The laser device 1 preferably automatically interrogates the delivery device 2 either upon connection of the delivery device 2 to the laser device 1 or upon switching the laser device 1 ON. [0056] Interrogation of the delivery device 2 at switch-on ensures that the laser device 1 detects whether a new delivery device 2 has been attached and whether or not the delivery device 2 is properly attached. The laser device 1 may also detect whether the delivery device 2 has been changed since the laser system 10 was last switched OFF. The laser device 1 preferably interrogates the delivery device 2 during or after completion of a self-test start-up procedure when the laser device 1 is first switched ON. [0057] According to an embodiment an interrogating electromagnetic pulse is preferably transmitted from the reader of the laser device 1 . The interrogating pulse may be of radio wave frequency. [0058] The AC or RF identification tag or transponder 3 is preferably powered by an electromagnetic field generated by the reader. The antenna of the AC or RF identification tag or transponder 3 collects electromagnetic energy transmitted by the reader. When the power pulse has been received the AC or RF identification tag or transponder 3 transmits data to the reader using the energy received. [0059] In an embodiment the RF or AC identification tag 3 may comprise either a conductively coupled RF or AC identification tag or a capacitively coupled RF or AC identification tag. The conductively coupled RF or AC identification tag may comprise a metal coil antenna powered by the magnetic field generated by the reader. [0060] A capacitively coupled RF or AC identification tag may comprise an antenna comprised of two plate electrodes. [0061] A capacitively coupled RF or AC identification tag is powered by an electric field generated by the reader, the field gradient causing a charge build up between the plates and thus a potential difference. In accordance with a less preferred embodiment a laser system 10 may be provided with an electromagnetic, tag which operates at a low frequency (typically between 70 Hz and 1 kHz). [0062] Upon receiving the data from the delivery device 2 the laser device 1 may be activated if the data indicates that the delivery device 2 is in a usable condition. However, if the delivery device 2 is not usable, for example if its expiry date has passed or its usage limit has been exceeded, then the laser device 1 may prevent or restrict further operation and/or may preferably provide the user with one or more warning messages. [0063] The laser device 1 may preferably receive information from the delivery device 2 which pre-configures the laser device 1 for use. For example, the laser device 1 may set the properties of the laser radiation to be transmitted to the delivery device. The settings may, for example, include the output power and/or pulse width and/or interval between pulses and/or the duration of the laser radiation. This may be particularly preferred in a medical laser device whereby the type of delivery device 2 and the settings for the laser device 1 may be specific to a particular treatment. [0064] According to an embodiment a user may be allowed to override the laser system 10 to allow further limited use of the laser system 10 , in for example emergency situations, when the laser device 1 has otherwise prevented use of the delivery device 2 . The override may be limited to a single occasion and may require resetting by service personnel. Alternatively a secure tool may be provided for resetting the override function. The secure tool may, for example, comprise a dummy-delivery device comprising a tag 3 , which transmits information to the laser device 1 and wherein the information resets the laser device 1 . The secure tool may be limited to a single use. The display 4 of the laser device 1 may indicate when the override function has been used. A telephone link, serial connection, internet link or other connection may be provided for enabling/disabling the laser device 2 and for overriding the information exchange, system. [0065] In one preferred embodiment the override function may be limited to situations wherein the laser device 1 has not received information from the delivery device 2 . [0066] Thus if the delivery device 2 , for example, indicated to the laser device 1 that it was unsuitable for use since the expiry date of the delivery device 2 had passed then the user may not be allowed to override the system. [0067] According to an embodiment the laser device 1 may only accept a delivery device 2 which transmits information to the laser device 1 . According to another embodiment the laser device 1 may operate with any delivery device 2 but will interrogate the delivery device 2 for information before operation. In a preferred embodiment whether the laser device 1 only operates with a delivery device 2 which transmits information or with any delivery device may be selectable. The selection between these modes of operation may be restricted such that only trained service personnel may set the mode of operation of the laser device 1 . For example, an internal switch may be provided or more preferably the system may be configured using a software engineering mode of the laser device 1 . [0068] This may be accessible via a telephone link, serial connection or the internet. A secure tool, as previously described, may also be used to configure the system. [0069] The delivery device 2 according to the preferred embodiment is preferably suitable for use with existing conventional laser devices which do not receive information from the delivery device 2 . [0070] The laser device 1 is preferably able to differentiate between separate delivery devices 2 such that the laser device 1 does not interrogate delivery devices other than the delivery device 2 actually attached to the laser device 1 . [0071] The device for interrogating the delivery device 1 , such as an AC or RF identification tag reader or a bar code reader, may be installed within a conventional laser device. The receiving of information from the delivery device 2 to the laser device 1 is preferably software driven, controlled and switched. The modification of a conventional laser device such that it is operable in accordance with the preferred embodiment preferably would not have any significant effect on the overall size, weight or reliability of the laser device. [0072] It will be appreciated that the above described embodiments are given by example only and that various modifications thereto may be made without departing from the scope of the invention.
A laser system ( 10 ) is disclosed comprising a laser device ( 1 ) for emitting laser radiation and an optical fibre ( 2 ) adapted to connect, in use, to the laser device ( 1 ) for delivering the laser radiation. The optical fibre contains a label ( 3 ), such as an RF identification tag, a barcode or a colour code. The laser device ( 1 ) interrogates the optical fibre ( 2 ) and receives information back from the optical fibre ( 2 ). If the usage of the optical fibre ( 2 ) has exceeded safety limits then the laser device ( 1 ) may be prevented from operating. The laser device ( 1 ) on receiving information from the optical fibre ( 2 ) may also be configured to deliver laser radiation having a specific power, pulse width, pulse interval and treatment duration.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] This is a continuation of U.S. application Ser.", "No. 10/521,383, filed Jan. 10, 2005, which is a national stage filing under 35 U.S.C. § 371 of International Application No. PCT/GB03/003205, filed Jul. 25, 2003, which is an international application of and claims priority to United Kingdom Application No. GB0217273.2, filed Jul. 25, 2002, all of which are incorporated herein by reference.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of Invention The present invention relates to a laser system and a method of operating a laser system.", "[0003] 2.", "Discussion of Related Art [0004] Medical lasers are used in certain medical procedures to administer thermal or other energy to a patient with beneficial effects.", "For example, energy can be used to detect or treat a tumour or a region of the body, or to destroy or denature diseased or malfunctioning body tissue.", "U.S. Pat. No. 6,095,149 describes, for example, the treatment of invertebral disc abnormalities with thermal energy.", "Other forms of medical treatment utilise laser energy such as endovenous laser treatment (EVLT) wherein laser energy is delivered to the inner wall of a vein.", "[0005] A known laser system comprises a laser device for emitting laser radiation and an optical fibre for directing the laser radiation to the required location.", "[0006] The laser system may be used for a variety of different purposes and optical fibres for use with the laser device may be provided with a standard connector for attachment to the laser device.", "[0007] Optical fibres used in conjunction with a laser device may, in certain circumstances, have a relatively limited lifetime.", "For example, the lifetime of an optical fibre may be limited due to hygiene requirements in medical applications.", "An optical fibre may additionally/alternatively also have a limited lifetime before it becomes susceptible to damage.", "[0008] A laser device may have been initially calibrated with a new optical fibre to deliver a certain intensity laser beam.", "However, if the optical fibre is reused a number of times then the presence of dirt etc.", "on the optical fibre may result in a lower than desired intensity laser beam being delivered which, for example in medical applications, could render the intended medical treatment ineffective.", "[0009] In some applications optical fibres may only be intended for single use and should be disposed of thereafterwards for health and safety reasons.", "EP 0473987 discloses a method and apparatus for optoelectrical recognition of disposable medical applicators connected to a laser.", "SUMMARY OF INVENTION [0010] According to an aspect of the present invention there is provided a laser system comprising: a laser device for emitting laser radiation;", "and a delivery device adapted to connect, in use, to the laser device for delivering the laser radiation;", "wherein, in use, the laser device receives information from the delivery device.", "[0011] An advantage of the preferred embodiment is that an operator can be certain that a correct, safe and effective optical fibre or other delivery device has been attached to the laser device and that the optical fibre or other delivery device is suitable for the intended use.", "This may be particularly important in medical applications.", "[0012] The delivery device is preferably an optical fibre and the laser device preferably includes a detector for detecting the connection of the delivery device.", "The laser device preferably interrogates the delivery device after detecting the connection.", "The laser device preferably interrogates the delivery device or optical fibre in a contactless manner.", "[0013] Information is preferably encoded, embedded within or otherwise stored with the delivery device and may indicate the type, usage, state, age, intended use and/or function of the delivery device.", "[0014] According to a preferred embodiment the delivery device comprises an AC or RF identification tag or transponder.", "The identification tag may be either a read only device or in an alternative embodiment a read/write device.", "[0015] The laser device preferably comprises an AC or RF identification reader for reading the AC or RF identification tag or transponder.", "In use, the delivery device preferably transmits or returns a signal to the AC or RF identification reader.", "[0016] According to a preferred embodiment the delivery device receives, in use, a power pulse.", "The delivery device preferably receives AC or RF energy, stores the energy and then transmits back to the laser device data or information using the stored energy.", "[0017] According to a less preferred embodiment the delivery device may comprise a barcode and the laser device may comprise a barcode reader.", "[0018] According to another less preferred embodiment the delivery device may comprise a colour identification tag and the laser device may identify the colour identification tag.", "[0019] The laser device preferably comprises a SMA-905 connector for receiving an optical fibre.", "[0020] According to a preferred embodiment in a mode of operation the laser device prevents operation with the delivery device upon receiving information from the delivery device.", "In a mode of operation the laser device may prevent operation with the delivery device if the laser device does not receive any information from the delivery device.", "The laser device may also prevent operation if a conventional delivery device known per se, for example a known delivery device which does not transmit information to the laser device, is connected to the laser device.", "[0021] The laser device may in a mode of operation prevent operation with the delivery device if the laser device receives information from the delivery device and wherein the information indicates a predetermined parameter is unsuitable or has been exceeded.", "The parameter may, for example, indicate the usage, sterility, type and/or expiry date of the delivery device.", "If the laser device does disable or limit operation with a delivery device then in a mode of operation the laser device may be enabled and/or disabled remotely, for example via a telephone link, a serial interface, via the internet or other means.", "[0022] The laser device may be provided with a visual display adapted to provide the user with information received from the delivery device.", "[0023] According to a preferred embodiment in a mode of operation the laser device receives information from the delivery device and sets the power and/or pulse width and/or interval between pulses and/or duration of laser radiation to be transmitted to the delivery device and hence delivered by the delivery device.", "Advantageously, this enables the laser device to be safely operated without requiring a skilled technician to control the operation of the laser device.", "[0024] According to another aspect of the present invention there is provided an optical fibre assembly comprising an AC or RF identification tag or transponder.", "[0025] According to another aspect of the present invention there is provided a laser device comprising a reader for reading an AC or RF identification tag or transponder on an optical fibre assembly.", "[0026] According to another aspect of the present invention there is provided a laser system comprising: an optical fibre assembly comprising an AC or RF identification tag or transponder;", "and a laser device comprising a reader for reading the AC or RF identification tag or transponder.", "[0027] According to another aspect of the present invention there is provided an optical fibre comprising a barcode.", "[0028] According to another aspect of the present invention there is provided a laser device comprising a barcode reader for reading a barcode on an optical fibre.", "[0029] According to another aspect of the present invention there is provided a laser system comprising: an optical fibre comprising a barcode;", "and a laser device comprising a barcode reader for reading the barcode.", "[0030] According to another aspect of the present invention there is provided a laser system comprising: a laser device for emitting laser radiation;", "and a delivery device adapted to connect, in use, to the laser device for delivering the laser radiation, the delivery device comprising a read/write device for storing information;", "wherein, in use, the laser device updates the information on the read/write device.", "[0031] Preferably, the laser system in accordance with any aspect of the present invention comprises a medical laser system.", "[0032] According to another aspect of the present invention there is provided a medical laser system comprising: a laser device for emitting laser radiation;", "and a delivery device adapted to connect, in use, to the laser device for delivering the laser radiation;", "wherein, in use, the laser device receives information from the delivery device.", "[0033] According to another aspect of the present invention there is provided a method of operating a laser system comprising the steps of: providing a laser device;", "and connecting a delivery device to the laser device;", "wherein said laser device receives information from the delivery device.", "[0034] According to another aspect of the present invention there is provided a method of operating a laser system comprising providing a laser device and a delivery device wherein the laser device interrogates the delivery device.", "Preferably, the laser device detects the attachment of the delivery device prior to interrogating the delivery device.", "[0035] According to another aspect of the present invention there is provided a method of operating a laser system comprising the steps of: providing a laser device;", "and attaching a delivery device to the laser device;", "wherein the laser device detects the attachment of the delivery device and interrogates the delivery device upon detection of the attachment of the delivery device.", "[0036] Preferably, the method of any aspect of the present invention further comprises the laser device enabling operation of the laser system upon receiving information from the delivery device.", "[0037] The laser device preferably receives information from the delivery device and displays the information for the user.", "The information received by the laser device from the delivery device may preferably indicate the usage, sterility, type or expiry date of the delivery device.", "[0038] A method of operating a laser system in accordance with any aspect of the present invention may preferably further include in a mode of operation the laser device being enabled and/or disabled remotely.", "[0039] According to another aspect of the present invention there is provided a method of operating a laser system comprising the steps of: providing a laser device;", "attaching a delivery device to a laser device;", "and transmitting a power pulse to the delivery device;", "wherein the delivery device receives the pulse, stores the pulse and transmits data to the laser device using the pulse.", "The pulse is preferably a pulse of AC or RF energy.", "[0040] Preferably, the laser device may receive information from the delivery device and configure the operation of the laser device.", "BRIEF DESCRIPTION OF DRAWINGS [0041] Various embodiments of the present invention will now be described, by way of example only, and with reference to the accompanying drawing in which: [0042] FIG. 1 shows a laser system according to the preferred embodiment.", "DETAILED DESCRIPTION [0043] A preferred embodiment of the present invention will now be described with reference to FIG. 1 .", "A laser system 10 is shown comprising a laser device 1 for emitting laser radiation and a delivery device 2 adapted and arranged to be connected to the laser device 1 .", "[0044] According to the preferred embodiment, the laser device 1 is an 810 nm diode laser manufactured by DIOMED, Ltd., United Kingdom and the delivery device 2 is an optical fibre.", "The delivery device 2 may be connected to the laser device 1 using any suitable connector/fibre terminator such as a standard sub-miniature A (SMA) connector.", "Alternatively, according to a less preferred embodiment, the delivery device may comprise a mirror based delivery system.", "[0045] The delivery device 2 is preferably fully compatible with existing systems.", "For example, the delivery device 2 is preferably suitable for interfacing with various accessories such as EVLT sheathes, spot handpieces and ENT accessories.", "[0046] Information from the delivery device 2 is received by the laser device 1 .", "Receiving information from the delivery device 2 preferably does not require any additional connection between the laser device 1 and the delivery device 2 , and a contactless method of receiving information from the delivery device 2 is particularly preferred.", "According to the preferred embodiment an AC or RF tag or transponder 3 is embedded within or provided on the delivery device 2 .", "The data or information received by the laser device 1 from the delivery device 2 is preferably pre-assigned to the delivery device 2 during manufacture.", "[0047] A reader for receiving information from the delivery device 2 is preferably provided within the laser device 1 .", "The reader may collect data or information which is then transferred through standard interfaces to the control of the laser device 1 .", "[0048] The reader provided within the laser device 1 may read an RF or AC identification tag or transponder 3 provided on the delivery device 2 .", "The reader preferably comprises an antenna, a transceiver and a processor.", "The RF or AC identification tag or transponder 3 preferably comprises an antenna and an integrated circuit or silicon chip.", "The RF or AC identification tag or transponder 3 may be encapsulated in glass or plastic which may then be attached to the delivery device 2 .", "[0049] In an embodiment the identification tag or transponder 3 may be a passive system which remains in an OFF state until activated by a signal from the reader.", "Preferably, the identification tag or transponder 3 is of the type which does not require an internal power source such as a battery.", "[0050] According to a preferred embodiment the AC or RF identification tag or transponder 3 is embedded within a moulding attached to the delivery device 2 e.g. optical fibre.", "The moulding is preferably attached to the delivery device 2 or optical fibre approximately 5 cm from a connector which is used to connect the optical fibre 2 to the laser device 1 .", "Thus, when the delivery device 2 or optical fibre is attached to the laser device 1 the identification tag or transponder 3 remains external to the laser device 1 .", "[0051] According to other embodiments the delivery device 2 may comprise a barcode or colour identification tag which is preferably located within the housing of the laser device 1 when the delivery device 2 is connected to the laser device 1 .", "[0052] The delivery device 2 is preferably able to withstand Ethylene Oxide sterilisation and accordingly an encapsulated AC or RF identification tag 3 is particularly preferred.", "[0053] The identification tag 3 may comprise a Read Only or a Read/Write device.", "The data held on the identification tag 3 may be pre-programmed onto the delivery device 2 during manufacture.", "If a Read/Write device is used the laser device 1 may update the information on the identification tag upon connection and may for example record the date and usage of the delivery device 2 .", "[0054] The information received by the laser device 1 is preferably displayed for the user on a display 4 which may be integral with the laser device 1 .", "The information may be displayed, for example, as a series of messages and/or warning (s) based on the data exchanged.", "[0055] The laser device 1 preferably automatically interrogates the delivery device 2 either upon connection of the delivery device 2 to the laser device 1 or upon switching the laser device 1 ON.", "[0056] Interrogation of the delivery device 2 at switch-on ensures that the laser device 1 detects whether a new delivery device 2 has been attached and whether or not the delivery device 2 is properly attached.", "The laser device 1 may also detect whether the delivery device 2 has been changed since the laser system 10 was last switched OFF.", "The laser device 1 preferably interrogates the delivery device 2 during or after completion of a self-test start-up procedure when the laser device 1 is first switched ON.", "[0057] According to an embodiment an interrogating electromagnetic pulse is preferably transmitted from the reader of the laser device 1 .", "The interrogating pulse may be of radio wave frequency.", "[0058] The AC or RF identification tag or transponder 3 is preferably powered by an electromagnetic field generated by the reader.", "The antenna of the AC or RF identification tag or transponder 3 collects electromagnetic energy transmitted by the reader.", "When the power pulse has been received the AC or RF identification tag or transponder 3 transmits data to the reader using the energy received.", "[0059] In an embodiment the RF or AC identification tag 3 may comprise either a conductively coupled RF or AC identification tag or a capacitively coupled RF or AC identification tag.", "The conductively coupled RF or AC identification tag may comprise a metal coil antenna powered by the magnetic field generated by the reader.", "[0060] A capacitively coupled RF or AC identification tag may comprise an antenna comprised of two plate electrodes.", "[0061] A capacitively coupled RF or AC identification tag is powered by an electric field generated by the reader, the field gradient causing a charge build up between the plates and thus a potential difference.", "In accordance with a less preferred embodiment a laser system 10 may be provided with an electromagnetic, tag which operates at a low frequency (typically between 70 Hz and 1 kHz).", "[0062] Upon receiving the data from the delivery device 2 the laser device 1 may be activated if the data indicates that the delivery device 2 is in a usable condition.", "However, if the delivery device 2 is not usable, for example if its expiry date has passed or its usage limit has been exceeded, then the laser device 1 may prevent or restrict further operation and/or may preferably provide the user with one or more warning messages.", "[0063] The laser device 1 may preferably receive information from the delivery device 2 which pre-configures the laser device 1 for use.", "For example, the laser device 1 may set the properties of the laser radiation to be transmitted to the delivery device.", "The settings may, for example, include the output power and/or pulse width and/or interval between pulses and/or the duration of the laser radiation.", "This may be particularly preferred in a medical laser device whereby the type of delivery device 2 and the settings for the laser device 1 may be specific to a particular treatment.", "[0064] According to an embodiment a user may be allowed to override the laser system 10 to allow further limited use of the laser system 10 , in for example emergency situations, when the laser device 1 has otherwise prevented use of the delivery device 2 .", "The override may be limited to a single occasion and may require resetting by service personnel.", "Alternatively a secure tool may be provided for resetting the override function.", "The secure tool may, for example, comprise a dummy-delivery device comprising a tag 3 , which transmits information to the laser device 1 and wherein the information resets the laser device 1 .", "The secure tool may be limited to a single use.", "The display 4 of the laser device 1 may indicate when the override function has been used.", "A telephone link, serial connection, internet link or other connection may be provided for enabling/disabling the laser device 2 and for overriding the information exchange, system.", "[0065] In one preferred embodiment the override function may be limited to situations wherein the laser device 1 has not received information from the delivery device 2 .", "[0066] Thus if the delivery device 2 , for example, indicated to the laser device 1 that it was unsuitable for use since the expiry date of the delivery device 2 had passed then the user may not be allowed to override the system.", "[0067] According to an embodiment the laser device 1 may only accept a delivery device 2 which transmits information to the laser device 1 .", "According to another embodiment the laser device 1 may operate with any delivery device 2 but will interrogate the delivery device 2 for information before operation.", "In a preferred embodiment whether the laser device 1 only operates with a delivery device 2 which transmits information or with any delivery device may be selectable.", "The selection between these modes of operation may be restricted such that only trained service personnel may set the mode of operation of the laser device 1 .", "For example, an internal switch may be provided or more preferably the system may be configured using a software engineering mode of the laser device 1 .", "[0068] This may be accessible via a telephone link, serial connection or the internet.", "A secure tool, as previously described, may also be used to configure the system.", "[0069] The delivery device 2 according to the preferred embodiment is preferably suitable for use with existing conventional laser devices which do not receive information from the delivery device 2 .", "[0070] The laser device 1 is preferably able to differentiate between separate delivery devices 2 such that the laser device 1 does not interrogate delivery devices other than the delivery device 2 actually attached to the laser device 1 .", "[0071] The device for interrogating the delivery device 1 , such as an AC or RF identification tag reader or a bar code reader, may be installed within a conventional laser device.", "The receiving of information from the delivery device 2 to the laser device 1 is preferably software driven, controlled and switched.", "The modification of a conventional laser device such that it is operable in accordance with the preferred embodiment preferably would not have any significant effect on the overall size, weight or reliability of the laser device.", "[0072] It will be appreciated that the above described embodiments are given by example only and that various modifications thereto may be made without departing from the scope of the invention." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens driving device for an auto-focusing camera. 2. Description of the Prior Art The camera lens driving device of the prior art is exemplified in Japanese Patent Laid-Open No. 62-200339. According to this camera lens driving device, in order that a lens driving member associated with a step motor may be stopped at a focal point, a retaining member for retaining the teeth of a ratchet wheel associated with the lens driving member is caused to retain the teeth of the ratchet wheel, when the step motor rotates to bring the lens driving member to the focal point, by an electromagnet thereby to restrain the lens driving member from further movement. However, the camera lens driving device of the prior art is troubled by the following problem. Because of the errors of the step angle of the step motor and/or the accumulated errors of the clearance due to the insufficient accuracy in the parts or the assembly of the power train from the step motor through the gear train (e.g., the idler gear), the moving member and the lens driving member to the ratchet wheel, the engagement between the ratchet wheel and the retaining member may not occur at the proper position thereby making the focusing improper. Therefore, a camera such as a multi-focal lens camera needing many lens stop positions is newly required to have means for stopping the lens driving member accurately in the many lens stop positions. This requirement is difficult to be satisfied within the limited operational space of the lens driving member and may increase the size of the camera. In order to stop the lens driving member accurately at the focal point, moreover, the clearance has to be reduced by improving the accuracy of the parts of their assembly but this is limited. In accordance with the number of the lens stop positions, still moreover, the ratchet wheel has to be enlarged to raise another problem that the camera is also large-sized. SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a camera lens driving device which is free of the aforementioned problems. According to the present invention, there is provided a camera lens driving device comprising: a lens driving member biased to move in one direction; a ratchet wheel having a plurality of teeth and associated with the lens driving member to rotate; a retaining member made rockable and having two pawl portions alternately meshing with the teeth of the ratchet wheel; an electromagnet for controlling the rocking motions of the retaining member; and a control circuit for outputting a signal to the electromagnet to control the biased movement of the lens driving member. According to the camera lens driving device thus described, the rocking motion of the retaining member is controlled by the electromagnet which in turn is controlled by the signal outputted from the control circuit. As a result, the retaining member has its two pawl portions alternately engaging with the teeth of the ratchet wheel by a predetermined number of times until its rocking motions are interrupted. Thus, the lens driving member biased to move in one direction can be stopped accurately at the focal point through the ratchet wheel. Thus, the retaining member is so controlled through the electromagnet by the control circuit that its pawl portions control the teeth of the ratchet wheel step by step to rotate intermittently. As a result, the ratchet wheel is stopped without fail after a predetermined number of steps independently of the step motor. Thus, it is possible to avoid the disadvantage of the prior art due to the step angle errors of the step motor. Moreover, the lens driving member is stopped by the meshing engagement with the stopped ratchet wheel while being biased in the one direction by a tension spring. As a result, it is possible to absorb the accumulated errors of the prior art in the clearance due to the accuracy of the parts and/or the assembly of the gear train from the step motor to the ratchet wheel. Thus, the lens driving member can be stopped accurately at the focal point. BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the present invention will become apparent from the following description taken with reference to the accompanying drawings, in which: FIG. 1 is a schematic diagram showing a first embodiment of the camera lens driving device before released according to the present invention; FIG. 2 is a diagram showing the operations of a step motor, a moving member, a lens driving member and an electromagnet, respectively, at (A) to (D); and FIG. 3 is a schematic diagram showing a second embodiment of the camera lens driving device according to the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the accompanying drawings. FIGS. 1 and 2 show the first embodiment of the camera lens driving device according to the present invention. FIG. 1 is a schematic diagram showing the lens driving device before it is released. Designated at reference numeral 1 is a moving member which is formed at its outer circumferential edge with: a gear portion 1a meshing through an idler gear 2 with a pinion 3a fixed on the output shaft of a step motor 3; a sector opening/closing cam 1b engaging with a pin 4a of a sector control lever 4 in an exposing region; and a pin 1c meshing with a later-described lens driving member 5. This lens driving member 5 is formed at its outer circumferential edge with: a projection 5a adapted to engage with a non-illustrated camera lens; a gear portion 5b meshing with a later-described ratchet wheel 7; and an abutting portion 5c adapted to engage with the pin 1c when the moving member 1 is rotated counterclockwise. Moreover, the lens driving member 5 is biased to rotate clockwise by the action of a tensile spring 6. The ratchet wheel 7 is supported rotatably and is formed with: a pinion portion 7a meshing with the gear portion 5b of the lens driving member 5; and a plurality of teeth 7b having a relation to a later-described retaining member 8. This retaining member 8 is supported in a rocking manner and is formed with: two pawl portions 8a adapted to engage with teeth 7b of the ratchet wheel 7; and an arm 8b for supporting an iron member 13 which is made of a magnetic material for coating with a later-described electromagnet 9. This electromagnet 9 can be magnetized and demagnetized by drive pulses (or signals) coming from a later-described control circuit 10, to attract the iron member 13 when it is magnetized. The control circuit 10 is made operative to output both drive pulses, that is drive pulses which are determined by the film sensitivity information and the object luminance information from a photometric unit 11 and which are fed to the step motor 3 and drive pulses which are determined by distance information obtained from a distance measuring unit 12, and which are fed to the electromagnet 9. The pawl portions 8a of the retaining member 8 are so related that when one of them is within the locus of rotation of the teeth 7b of the ratchet wheel 7 the other is positioned outside of the locus of rotation, thus providing an escapement in which the relation is reversed when the retaining member 8 rocks. When the electromagnet 9 is in its deenergized state, the retaining member 8 is caused to repeat its rocking motion through the ratchet wheel 7 by the tensile spring 6 which biases the lens driving member 5 rotationally. When in the magnetized state, the electromagnet 9 attracts and fixes the iron member 13 thereby to control the rotation of the lens driving member 5 through the retaining member 8 and the ratchet wheel 7. The operations of the first embodiment thus constructed will be described with reference to the following additional operation diagram of FIG. 2. By the operation of a non-illustrated release, drive pulses to the step motor 3 and the electromagnet 9 are determined by the control circuit 10 in accordance with the information from the photometric unit 11 and the distance measuring unit 12 and are outputted from the control circuit 10 to the step motor 3 and the electromagnet 9. First of all, as shown at (A) and (B) in FIG. 2, the step motor 3 rotates forward to turn the moving member 1 clockwise. Then, the lens driving member 5 is biased clockwise by the tensile spring 6. At the same time, the electromagnet 9 is repeatedly energized and deenergized by the drive pulses coming from the control circuit 10 to rock the retaining member 8 back and forth. Thus, the lens driving member 5 starts its clockwise rotation through the ratchet wheel 7. After this, the electromagnet 9 ends the repetitions of the magnetization and demagnetization by the predetermined drive pulses from the control circuit 10. Then, a drive pulse for continuing the magnetization is outputted from the control circuit 10. This state is held after the operation of the retaining member 8, the ratchet wheel 7 and the lens driving member 5 are stopped (as indicated at a in FIG. 2(C)) and until the non-illustrated camera lens is focused to complete the exposure. Even after the operation of the lens driving member 5 is stopped, the clockwise rotation of the moving member 1 is continued by the forward rotation of the step motor 3 until the exposure region is reached (as indicated at El in FIG. (2A)). The step motor 3 is further rotated forward by the drive pulses of the control circuit 10 determined by the object luminance information so that the pin 4a of the sector control lever 4 comes into engagement with the sector opening/closing cam 1b of the moving member 1. As a result, the sector control lever 4 is turned counter-clockwise to open non-illustrated sectors gradually for effecting the exposure. At the instant (as indicated at b in FIG. 2(A)) when an aperture matching the proper exposure is formed, the step motor 3 is rotated backward by the backward drive pulses for the control circuit 10. As a result, the moving member 1 is rotated counter-clockwise to close the sectors thereby to complete the exposure (as indicated at E2 in FIG. 2(A)). After this, the step motor 3 continues its backward rotation to return the moving member 1 to its initial position. At the instant (as indicated at c in FIG. 2(C)) when the pine 1c of the moving member 1 comes into contact with the abutting portion 5c of the lens driving member 5, the electromagnet 9 is demagnetized (as indicated at d in FIG. 2(D)) by the control circuit 10, and the retaining member 8 is allowed to rock freely. As a result, the lens driving member 5 is rotated counter-clockwise together with the moving member 1 while charging the biasing force of the tensile spring 6, until the operation is ended when the step motor 3 is stopped. FIG. 3 shows a second embodiment of the present invention. In this embodiment, the ratchet wheel 7 and the retaining member 8, which are associated with the lens driving member 5 biased clockwise by the tensile spring 6, are constructed like the first embodiment. In FIG. 3 the retaining member 8 has an arm 8b which engages the iron member 13 which is attractable by an electromagnet 19 and supported to move horizontally by non-illustrated means. Like the first embodiment, the electromagnet 19 is composed of: a coil 19a connected with a non-illustrated control circuit (which can be the same control circuit as shown in FIG. 1); two magnetic cores 19b; and a permanent magnet 19c sandwiched between the magnetic cores 19b and magnetized to have N and S poles. When the coil 19a is deenergized, the iron member 13 is attracted to the magnetic cores 19b by the magnetic force of the permanent magnet 19c. When the coil 19a is energized, the magnetic force of the permanent magnet 19c is demagnetized to release the attraction of the iron member 13 from the magnetic cores 19b. When the electromagnet 19 is not operated, the magnetic cores 19b attract and fix the iron member 13 which controls the operation of the retaining member 8, the ratchet wheel 7 and the lens driving member 5. When the electromagnet 19 is operated, the iron member 13 can be operated in the horizontal direction so that the lens driving member 5 can be operated through the retaining member 8 and the ratchet wheel 7. These operations are similar to those of the first embodiment. According to the second embodiment, the electromagnet 19 can attract the iron member 13 no matter which of the two end positions of the rocking range might be taken by the arm 8b of the retaining member 8. As a result, the step angles of the ratchet wheel 7 and the lens driving member 5 can be halved to provide an advantage in the design that the number of lens stops is increased and that the device is made compact. The structure, like the first embodiment, in which the biasing force of the spring for rotating the lens driving member 5 is applied through the moving member 1 to the step motor 3, is held against the biasing force of the spring, when the camera is not used, by the magnetic coupling force of the non-illustrated stator and rotor of the step motor 3. When shocks are applied to the camera, there may arise a malfunction in which the balance is lost and thereby damage the magnetic phase relation between the stator and the rotor so that the initial position is moved to make the operations inaccurate. According to this second embodiment, on the contrary, the electromagnet 19 attracts the iron member 13 when it is deenergized, so that the operations of the retaining member 8, the ratchet wheel 7 and the lens driving member 5 are controlled when the camera is not used. Thus, the aforementioned malfunction can be prevented. The moving member 1 in the foregoing embodiments accomplishes both the focusing and exposing operations by the step motor 3. However, the present invention may be applied to a camera which is used for accomplishing only a focusing operation. The drive source need not be limited to the step motor but may be exemplified by a bi-directional DC motor or ultrasonic motor. The structure may be modified such that the spring is charged up by returning the lens driving member 5 manually to the initial position. In order that the lens driving member 5 in the first embodiment may be prevented from being rotated by the biasing force of the tensile spring 6 after the return, the lens driving member 5 in the initial position may be retained by another member and released by the releasing operation of the camera. As has been described hereinbefore, according to the camera lens driving device of the present invention, the ratchet wheel is stopped without fail after the predetermined steps independently of the step motor. Thus, it is possible to prevent the disadvantage which might otherwise be caused in the prior art due to the errors of the step angle of the step motor. Moreover, the lens driving member is stopped by the meshing engagement with the stopped ratchet wheel while being biased in the one direction by the tensile spring. Thus, the accumulated errors of the prior art in the clearance due to the accuracy in the individual parts and their assembly such as the gear train from the step motor to the ratchet wheel can be avoided to stop the lens driving member accurately at the focal point. According to the second embodiment, moreover, an advantage can be achieved in the number of the lens stops and in the size reduction for the same number of stops. Even if a shock is applied to the unused camera, it is possible to prevent a malfunction due to the displacement of the initial position of the step motor. Although the present invention has been described through specific terms, it should be noted here that the described embodiment is not necessarily exclusive and that various changes and modifications may be imparted thereto without departing from the scope of the invention which is limited solely by the appended claim.
A lens driving device for an auto-focusing camera includes a lens driving member biased to move in one direction, a ratchet wheel having a plurality of teeth and rotatably associated with the lens driving member, a rockable retaining member having two pawl portions alternately engaging the teeth of the ratchet wheel, an electromagnet for controlling the rocking motions of the retaining member, and a control circuit for outputting a signal to the electromagnet to control the biased movement of the lens driving member.
Identify the most important claim in the given context and summarize it
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to a lens driving device for an auto-focusing camera.", "Description of the Prior Art The camera lens driving device of the prior art is exemplified in Japanese Patent Laid-Open No. 62-200339.", "According to this camera lens driving device, in order that a lens driving member associated with a step motor may be stopped at a focal point, a retaining member for retaining the teeth of a ratchet wheel associated with the lens driving member is caused to retain the teeth of the ratchet wheel, when the step motor rotates to bring the lens driving member to the focal point, by an electromagnet thereby to restrain the lens driving member from further movement.", "However, the camera lens driving device of the prior art is troubled by the following problem.", "Because of the errors of the step angle of the step motor and/or the accumulated errors of the clearance due to the insufficient accuracy in the parts or the assembly of the power train from the step motor through the gear train (e.g., the idler gear), the moving member and the lens driving member to the ratchet wheel, the engagement between the ratchet wheel and the retaining member may not occur at the proper position thereby making the focusing improper.", "Therefore, a camera such as a multi-focal lens camera needing many lens stop positions is newly required to have means for stopping the lens driving member accurately in the many lens stop positions.", "This requirement is difficult to be satisfied within the limited operational space of the lens driving member and may increase the size of the camera.", "In order to stop the lens driving member accurately at the focal point, moreover, the clearance has to be reduced by improving the accuracy of the parts of their assembly but this is limited.", "In accordance with the number of the lens stop positions, still moreover, the ratchet wheel has to be enlarged to raise another problem that the camera is also large-sized.", "SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a camera lens driving device which is free of the aforementioned problems.", "According to the present invention, there is provided a camera lens driving device comprising: a lens driving member biased to move in one direction;", "a ratchet wheel having a plurality of teeth and associated with the lens driving member to rotate;", "a retaining member made rockable and having two pawl portions alternately meshing with the teeth of the ratchet wheel;", "an electromagnet for controlling the rocking motions of the retaining member;", "and a control circuit for outputting a signal to the electromagnet to control the biased movement of the lens driving member.", "According to the camera lens driving device thus described, the rocking motion of the retaining member is controlled by the electromagnet which in turn is controlled by the signal outputted from the control circuit.", "As a result, the retaining member has its two pawl portions alternately engaging with the teeth of the ratchet wheel by a predetermined number of times until its rocking motions are interrupted.", "Thus, the lens driving member biased to move in one direction can be stopped accurately at the focal point through the ratchet wheel.", "Thus, the retaining member is so controlled through the electromagnet by the control circuit that its pawl portions control the teeth of the ratchet wheel step by step to rotate intermittently.", "As a result, the ratchet wheel is stopped without fail after a predetermined number of steps independently of the step motor.", "Thus, it is possible to avoid the disadvantage of the prior art due to the step angle errors of the step motor.", "Moreover, the lens driving member is stopped by the meshing engagement with the stopped ratchet wheel while being biased in the one direction by a tension spring.", "As a result, it is possible to absorb the accumulated errors of the prior art in the clearance due to the accuracy of the parts and/or the assembly of the gear train from the step motor to the ratchet wheel.", "Thus, the lens driving member can be stopped accurately at the focal point.", "BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the present invention will become apparent from the following description taken with reference to the accompanying drawings, in which: FIG. 1 is a schematic diagram showing a first embodiment of the camera lens driving device before released according to the present invention;", "FIG. 2 is a diagram showing the operations of a step motor, a moving member, a lens driving member and an electromagnet, respectively, at (A) to (D);", "and FIG. 3 is a schematic diagram showing a second embodiment of the camera lens driving device according to the present invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the accompanying drawings.", "FIGS. 1 and 2 show the first embodiment of the camera lens driving device according to the present invention.", "FIG. 1 is a schematic diagram showing the lens driving device before it is released.", "Designated at reference numeral 1 is a moving member which is formed at its outer circumferential edge with: a gear portion 1a meshing through an idler gear 2 with a pinion 3a fixed on the output shaft of a step motor 3;", "a sector opening/closing cam 1b engaging with a pin 4a of a sector control lever 4 in an exposing region;", "and a pin 1c meshing with a later-described lens driving member 5.", "This lens driving member 5 is formed at its outer circumferential edge with: a projection 5a adapted to engage with a non-illustrated camera lens;", "a gear portion 5b meshing with a later-described ratchet wheel 7;", "and an abutting portion 5c adapted to engage with the pin 1c when the moving member 1 is rotated counterclockwise.", "Moreover, the lens driving member 5 is biased to rotate clockwise by the action of a tensile spring 6.", "The ratchet wheel 7 is supported rotatably and is formed with: a pinion portion 7a meshing with the gear portion 5b of the lens driving member 5;", "and a plurality of teeth 7b having a relation to a later-described retaining member 8.", "This retaining member 8 is supported in a rocking manner and is formed with: two pawl portions 8a adapted to engage with teeth 7b of the ratchet wheel 7;", "and an arm 8b for supporting an iron member 13 which is made of a magnetic material for coating with a later-described electromagnet 9.", "This electromagnet 9 can be magnetized and demagnetized by drive pulses (or signals) coming from a later-described control circuit 10, to attract the iron member 13 when it is magnetized.", "The control circuit 10 is made operative to output both drive pulses, that is drive pulses which are determined by the film sensitivity information and the object luminance information from a photometric unit 11 and which are fed to the step motor 3 and drive pulses which are determined by distance information obtained from a distance measuring unit 12, and which are fed to the electromagnet 9.", "The pawl portions 8a of the retaining member 8 are so related that when one of them is within the locus of rotation of the teeth 7b of the ratchet wheel 7 the other is positioned outside of the locus of rotation, thus providing an escapement in which the relation is reversed when the retaining member 8 rocks.", "When the electromagnet 9 is in its deenergized state, the retaining member 8 is caused to repeat its rocking motion through the ratchet wheel 7 by the tensile spring 6 which biases the lens driving member 5 rotationally.", "When in the magnetized state, the electromagnet 9 attracts and fixes the iron member 13 thereby to control the rotation of the lens driving member 5 through the retaining member 8 and the ratchet wheel 7.", "The operations of the first embodiment thus constructed will be described with reference to the following additional operation diagram of FIG. 2. By the operation of a non-illustrated release, drive pulses to the step motor 3 and the electromagnet 9 are determined by the control circuit 10 in accordance with the information from the photometric unit 11 and the distance measuring unit 12 and are outputted from the control circuit 10 to the step motor 3 and the electromagnet 9.", "First of all, as shown at (A) and (B) in FIG. 2, the step motor 3 rotates forward to turn the moving member 1 clockwise.", "Then, the lens driving member 5 is biased clockwise by the tensile spring 6.", "At the same time, the electromagnet 9 is repeatedly energized and deenergized by the drive pulses coming from the control circuit 10 to rock the retaining member 8 back and forth.", "Thus, the lens driving member 5 starts its clockwise rotation through the ratchet wheel 7.", "After this, the electromagnet 9 ends the repetitions of the magnetization and demagnetization by the predetermined drive pulses from the control circuit 10.", "Then, a drive pulse for continuing the magnetization is outputted from the control circuit 10.", "This state is held after the operation of the retaining member 8, the ratchet wheel 7 and the lens driving member 5 are stopped (as indicated at a in FIG. 2(C)) and until the non-illustrated camera lens is focused to complete the exposure.", "Even after the operation of the lens driving member 5 is stopped, the clockwise rotation of the moving member 1 is continued by the forward rotation of the step motor 3 until the exposure region is reached (as indicated at El in FIG. (2A)).", "The step motor 3 is further rotated forward by the drive pulses of the control circuit 10 determined by the object luminance information so that the pin 4a of the sector control lever 4 comes into engagement with the sector opening/closing cam 1b of the moving member 1.", "As a result, the sector control lever 4 is turned counter-clockwise to open non-illustrated sectors gradually for effecting the exposure.", "At the instant (as indicated at b in FIG. 2(A)) when an aperture matching the proper exposure is formed, the step motor 3 is rotated backward by the backward drive pulses for the control circuit 10.", "As a result, the moving member 1 is rotated counter-clockwise to close the sectors thereby to complete the exposure (as indicated at E2 in FIG. 2(A)).", "After this, the step motor 3 continues its backward rotation to return the moving member 1 to its initial position.", "At the instant (as indicated at c in FIG. 2(C)) when the pine 1c of the moving member 1 comes into contact with the abutting portion 5c of the lens driving member 5, the electromagnet 9 is demagnetized (as indicated at d in FIG. 2(D)) by the control circuit 10, and the retaining member 8 is allowed to rock freely.", "As a result, the lens driving member 5 is rotated counter-clockwise together with the moving member 1 while charging the biasing force of the tensile spring 6, until the operation is ended when the step motor 3 is stopped.", "FIG. 3 shows a second embodiment of the present invention.", "In this embodiment, the ratchet wheel 7 and the retaining member 8, which are associated with the lens driving member 5 biased clockwise by the tensile spring 6, are constructed like the first embodiment.", "In FIG. 3 the retaining member 8 has an arm 8b which engages the iron member 13 which is attractable by an electromagnet 19 and supported to move horizontally by non-illustrated means.", "Like the first embodiment, the electromagnet 19 is composed of: a coil 19a connected with a non-illustrated control circuit (which can be the same control circuit as shown in FIG. 1);", "two magnetic cores 19b;", "and a permanent magnet 19c sandwiched between the magnetic cores 19b and magnetized to have N and S poles.", "When the coil 19a is deenergized, the iron member 13 is attracted to the magnetic cores 19b by the magnetic force of the permanent magnet 19c.", "When the coil 19a is energized, the magnetic force of the permanent magnet 19c is demagnetized to release the attraction of the iron member 13 from the magnetic cores 19b.", "When the electromagnet 19 is not operated, the magnetic cores 19b attract and fix the iron member 13 which controls the operation of the retaining member 8, the ratchet wheel 7 and the lens driving member 5.", "When the electromagnet 19 is operated, the iron member 13 can be operated in the horizontal direction so that the lens driving member 5 can be operated through the retaining member 8 and the ratchet wheel 7.", "These operations are similar to those of the first embodiment.", "According to the second embodiment, the electromagnet 19 can attract the iron member 13 no matter which of the two end positions of the rocking range might be taken by the arm 8b of the retaining member 8.", "As a result, the step angles of the ratchet wheel 7 and the lens driving member 5 can be halved to provide an advantage in the design that the number of lens stops is increased and that the device is made compact.", "The structure, like the first embodiment, in which the biasing force of the spring for rotating the lens driving member 5 is applied through the moving member 1 to the step motor 3, is held against the biasing force of the spring, when the camera is not used, by the magnetic coupling force of the non-illustrated stator and rotor of the step motor 3.", "When shocks are applied to the camera, there may arise a malfunction in which the balance is lost and thereby damage the magnetic phase relation between the stator and the rotor so that the initial position is moved to make the operations inaccurate.", "According to this second embodiment, on the contrary, the electromagnet 19 attracts the iron member 13 when it is deenergized, so that the operations of the retaining member 8, the ratchet wheel 7 and the lens driving member 5 are controlled when the camera is not used.", "Thus, the aforementioned malfunction can be prevented.", "The moving member 1 in the foregoing embodiments accomplishes both the focusing and exposing operations by the step motor 3.", "However, the present invention may be applied to a camera which is used for accomplishing only a focusing operation.", "The drive source need not be limited to the step motor but may be exemplified by a bi-directional DC motor or ultrasonic motor.", "The structure may be modified such that the spring is charged up by returning the lens driving member 5 manually to the initial position.", "In order that the lens driving member 5 in the first embodiment may be prevented from being rotated by the biasing force of the tensile spring 6 after the return, the lens driving member 5 in the initial position may be retained by another member and released by the releasing operation of the camera.", "As has been described hereinbefore, according to the camera lens driving device of the present invention, the ratchet wheel is stopped without fail after the predetermined steps independently of the step motor.", "Thus, it is possible to prevent the disadvantage which might otherwise be caused in the prior art due to the errors of the step angle of the step motor.", "Moreover, the lens driving member is stopped by the meshing engagement with the stopped ratchet wheel while being biased in the one direction by the tensile spring.", "Thus, the accumulated errors of the prior art in the clearance due to the accuracy in the individual parts and their assembly such as the gear train from the step motor to the ratchet wheel can be avoided to stop the lens driving member accurately at the focal point.", "According to the second embodiment, moreover, an advantage can be achieved in the number of the lens stops and in the size reduction for the same number of stops.", "Even if a shock is applied to the unused camera, it is possible to prevent a malfunction due to the displacement of the initial position of the step motor.", "Although the present invention has been described through specific terms, it should be noted here that the described embodiment is not necessarily exclusive and that various changes and modifications may be imparted thereto without departing from the scope of the invention which is limited solely by the appended claim." ]
TECHNICAL FIELD The technical field of the invention is automatic electrically operated cameras, and in particular range sensing systems for battery-powered cameras. BACKGROUND ART In battery-powered cameras there have long been known a variety of range sensing systems for automatically setting the focus of the lens to correspond to the distance of an object centrally located in the field of view, or alternatively for adjusting the aperture in flash mode where the aperture setting is also a range-dependent parameter. Such systems have employed ultrasonic or infra-red signals directed at the object of interest. The infra-red signal sources were generally gas filled flash lamps. In some cases, the same flash lamp used for illuminating the subject is also used in a pre-flash mode to first generate the range determining signal. In other cameras, a separate gas flash lamp is used for range determining purposes. In either case, the distance of the object from the camera is determined by measuring the amplitude of the reflected signal. The use of gas filled flash lamps as the source of infra-red energy is relatively costly as compared, for example, to the cost of using infra-red light emitting diodes; however, the intensity of the energy directed by such diode sources has heretofore been of such low intensity that it is believed that only a triangulation means using relatively expensive circuitry for determining range was thought to be practical. An example of a ranging system which uses a triangulation based measuring system is currently marketed by Hamamatsu Photonics of Hamamatsu City, Japan, and is described in their technical data sheet entitled "Autofocus Devices" dated March, 1984. The system described therein is based upon an optical triangulation system wherein a light-emitting diode is powered at relatively low power and focused into a beam directed at an object centrally located in the scene to be photographed. A position sensing diode is disposed to receive reflected light focused thereon by a lens, the position of the spot on the diode being used to derive a difference signal used to govern signal processing circuitry so that the output signal used to govern the relevant camera parameter is related to the range of the object. The photosensing diode is a three-terminal device in the form of a P-I-N diode having a common electrode on the rear face thereof and a pair of output electrodes disposed on the light-receiving face on either side of a central sensing region. The position sensing diode is operated in biased photovoltaic mode, and appears to provide a voltage difference at the two output terminals according to the position of the incident light spot with respect to the center of symmetry of the structure. The signal processing circuitry associated with such a device appears to be quite complex, involving a pair of signal processing circuits. Each signal processing circuit in turn feeds a distance calculation circuit, the output of which is fed to a sample-and-hold or alternatively to an analog-to-digital converter to govern the adjustment of the relevant camera parameter. The circuitry necessary to accomplish this is quite expensive, and the photosensing diode itself, being a three-terminal device, is expensive because of the number of terminals alone, as well as because of the highly specialized nature of the device itself. Additionally, the light emitting diode appears to be driven at a relatively low power level of 10 milliwatts, which would raise a severe signal-to-noise problem. This in all likelihood requires a continuous modulation of the diode driver power, coupled with some form of synchronous detection in the signal processing circuitry; however, no such feature is shown explicitly in the aforementioned Data Sheet. There remains a need in the case of cameras for the intermediate price market for an inexpensive infra-red range sensing system which does not have the complexity, and hence the expense, of the systems of the type described hereinabove. Moreover, as applied to cameras having two-position lenses wherein the lens is set to either a far-focus position placing the distant edge of the field at infinity (the hyperfocal distance) or to a near-focus setting substantially closer than the hyperfocal setting, a simple range finding system capable of providing reliable ranging information for objects out to no more than 15 feet or so would be more than adequate, provided that it can be accomplished at minimum cost. To the applicant's knowledge, no such system has yet been provided. SUMMARY OF THE INVENTION According to a feature of the invention, a camera range-finding system employs an infra-red light-emitting diode operated in pulse mode to produce a single relatively high amplitude pulse of infra-red light confined by directing means, preferably in the form of a lens, to define a relatively narrow cone of illumination projected into a generally centrally located region of the field of view. An infra-red sensing diode receives the reflected light from a second directing means, again preferably in the form of a lens, which focuses light reflected from an object in this centrally located region onto a detecting diode to produce an excitation signal having an amplitude which increases generally according to the amount of light received by the second directing means. In the preferred form of the invention, the amplitude of this signal is used to set one or more latching comparators which govern the terminal position of a lens drive system, or alternatively an aperture drive system, to adjust these image-affecting parameters according to the strength of the received radiation, and hence according to the distance to the object. According to specific features of the invention, the light emitting diode is driven in a short pulsed mode wherein a short current pulse is applied to excite the diode, the pulse current being substantially greater than the maximum steady-state rated current of the diode, and in the preferred embodiment, being at least an order of magnitude greater. According to a further specific feature of the invention, the light-emitting diode is provided with its excitation current from a bank of two or more capacitors which are charged in parallel from a regulated battery voltage of 2.0 volts and discharged in series, thereby boosting the excitation voltage and allowing diodes of the gallium arsenide family having relatively high excitation voltages to be successfully employed even if the source 3.0 volt battery becomes weak. The resulting ranging system is reliable up to ranges of at least 15 feet, and thus provides the desired inexpensive control of the camera. Other features and advantages of the invention will become apparent upon making reference to the specification and claims to follow and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block schematic diagram of the principal elements of an electrically operated camera deriving range information from an emitted and reflected light pulse using the amplitude of the reflected pulse to adjust either lens focus or lens aperture. FIG. 2 is a schematic diagram of a circuit for producing electrical pulses to energize a light emitting diode. FIG. 3 is a pulse detection circuit for converting a received light pulse to a control signal used to control a camera setting. DETAILED DESCRIPTION While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail a preferred embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention, and is not intended to limit the broad aspect of the invention to the embodiment illustrated. FIG. 1 is a block schematic diagram showing in general form the principal aspects of the present invention as applied to adjusting an image-affecting parameter of a camera, i.e., the focus setting of the lens or the aperture setting, according to the distance to the object to be photographed. The camera aperture setting, is, as is well known, a range-dependent variable when the camera is operated in flash mode. In the description to follow concerning FIG. 1, discussion will be directed toward the provision of three or more parameter settings, whereas the subsequent discussion of the circuitry implementing the concepts of the present invention as shown in FIGS. 2 and 3 will be oriented towards a simpler two-position focusing system based upon similar principles. Considering FIG. 1 in more detail, power is applied from a battery to a power supply 10. A lens cover slide 7 is coupled to a pair of switches 5, 6 which are actuated responsively to moving the slide to uncover the lens preparatory to using the camera. Closure of switch 5 brings the power supply to an active condition, immediately supplying regulated voltages of 2.0 and 0.5 volts, and an unregulated voltage of 3.0 volts to power the various elements of the system. Switch 6 is a momentary contact switch which momentarily closes after the closure of switch 5 and after the power supply output voltages have been established, thereafter breaking contact. During this interval 3.0 volts are momentarily supplied to control line L2, after which time this voltage reverts to zero. As will subsequently be discussed, the reversion of line L2 to a low state is used to stabilize various aspects of the circuit into a proper configuration for signal processing. Subsequent actuation of a manually operated shutter release button 3 again raises control line L2 to a high state to trigger a pulse unit 12 to provide a short pulse of current to a light-emitting diode 14. Light from the infrared light-emitting diode 14 is focused into a relatively narrow beam 18 illuminating a central region of the scene of interest. Light 20 reflected from an object generally centrally located in the scene is received by lens 22 and focused on a light-sensing diode 24. The excitation received by diode 24 thus varies with the distance to the object from which the outgoing beam 18 is reflected. This excitation signal is processed by a detector unit 26 to provide on output line L4 a signal varying in amplitude with the magnitude of excitation received by the light-sensing diode 24. The remainder of the system is best understood with reference to U.S. Pat. No. 4,473,285 issued to Winter, wherein there is described a system generally similar to that shown in FIG. 1. A plurality of comparators 28, 30 (and more if desired) are provided, each comparator being of the latching type and having a different triggering threshold. The system shown in FIG. 1 is particularized to a three-range system. Under extremely weak conditions, the signal on line L4 will be insufficient to trigger either of the comparators 28, 30. This corresponds to objects at very far distances, requiring for example, the maximum-range focus setting of the camera lens. If the object is at an intermediate distance, then latching comparator 30 will trigger, but latching comparator 28 will not. For extremely close objects, both of the comparators 28, 30 will be triggered. The respective comparator outputs are placed on lines L6 and L8 respectively. As described in the Winter patent, an electromechanical adjustment system 41 includes a rotary contact 38 having, in this case, three contacting pads 32, 34, 36 is driven into scanning rotation by a motor 40 upon total depression of the shutter button 3. This motor is typically of the spring-driven variety, being energized and cocked during the film advance process. Full operation of the shutter release button 3 releases the rotor 38 to sequentially contact the pads 32, 34, 36 in the order shown. As the rotor 38 contacts each of the pads 32, 34, 36 serially, the voltage supplied thereto from the latching comparators 28, 30 is sensed by a controller 42. In the event that a close object has caused the amplitude on line L4 to be quite high, both comparators 28, 30 will be latched to a presence-sensing state, as a result of which the rotor 38, upon contacting pad 32 will immediately relay this condition to the controller 42, which in turn operates a solenoid brake or latch 44, which acts to freeze the rotation of the rotor 38 on pad 32. The photographic objective lens 41 is synchronously coupled to the rotation of rotor 38 via the rotation of the motor 40 to be driven thereby through a range of focus settings. Such a system is fully disclosed in the above-referenced Winter patent. Thus, the solenoid brake 44 freezes the operation of the lens focusing system upon contacting the close-distance pad 32, establishing the focusing of the lens 41 for a close object. In the event that the object is at an intermediate range capable of triggering only comparator 30, then the rotor 38 will continue its rotation until encountering the presence-indicating signal present on pad 34, thus terminating the motion of the lens at 41 the intermediate-focusing position. Finally, if neither comparator has been triggered, indicating a very distant object, then rotation continues to the extreme possible travel of the rotor 38 (and hence the lens 41) to terminate on pad 36, which corresponds to a mechanical limit stop in the focusing system of the lens 41. The lens 41 is now set for farthest focus. Responsively to final total depression of the shutter release button 3, a shutter actuator 46 actuates the shutter through an exposure cycle. Alternatively, a similar synchronously driven rotor may be employed in conjunction with a lens aperture control system for flash mode operation, such a system also being described in the above-referenced Winter patent. FIG. 2 shows the circuit which produces a single pulse of infrared light from the light-emitting diode 14 responsively to the voltage pulse received via line L2 from the shutter release switch 8. Considering the pulse unit of FIG. 2 in more detail, the purpose of this unit is to charge diode energizing capacitors C2, C3 to essentially the full regulated 2.0 volts, and thereafter to deliver this charge to the light-emitting diode 14 as a short pulse responsively to the triggering pulse on line L2. The light-emitting diode 14 in the present embodiment is the infrared type TLN115 made by Toshiba. This diode 14 is operated in a pulse mode wherein a current of one ampere, the recommended maximum pulse current, is supplied initially to the diode to provide a current pulse decaying to the diode threshold turn-on value in approximately 90 microseconds. This pulsed operation is to be compared with the recommended maximum continuous operating current 100 milliamperes for such a unit. Being of the gallium arsenide family, this diode 14 requires a minimum of 2.2 volts in the forward direction for light emission. The present design is oriented towards use of a battery of 3.0 volts regulated down to 2.0 volts to provide for uniform excitation to the light-emitting diode 14. As will next be discussed, proper energizing current for the light-emitting diode 14 is achieved by charging the two discharge capacitors C2, C3 in parallel from the regulated 2.0 volt supply and thereafter discharging them in series through the diode. The foregoing is accomplished by holding transistors Q1 and Q2 open in charging mode, whereafter they are both turned on to connect the capacitors C2, C3 in series to discharge them through the diode 14. In more detail, with transistors Q1 and Q2 off, then capacitor C3 is charged through resistors R8 and R10 from the 2.0 volt supply, placing the negative terminal of this capacitor at ground. Capacitor C2 is charged at the positive terminal thereof through resistor R9 from the positive 2.0 volt supply, and has the negative terminal thereof grounded through resistor R7. Transistors Q1 and Q2 are of the low saturation voltage type. When transistors Q1 and Q2 are turned on the current into the diode 14 flows from capacitor C3 through transistor Q1, through capacitor C2, (now connected in series with capacitor C3), and through transistor Q2. Thus, although capacitor C2 and C3 were charged in parallel from the 2.0 volt supply in charge mode, in discharge mode they are effectively connected in series with the diode 14. Simultaneous triggering of transistors Q1 and Q2 is achieved by simultaneous operation of the amplitude comparators AC1 and AC2. Each comparator has its noninverting input terminal connected to regulated 0.5 volts, and the inverting input terminal connected to the battery voltage pulse provided on line L2 and attenuated to approximately 1.0 volts or thereabouts by the attenuating pair R1, R2. Before the arrival of the trigger pulse, the 0.5 volt reference level applied to the noninverting input of the comparators AC1 and AC2 acts to produce an open circuit at the output thereof. These comparators AC1 and AC2 are of the open-collector type, their output stage collectors being essentially grounded when a positive signal greater than the 0.5 volt reference is applied to their inverting inputs. This will occur whenever the voltage pulse arriving on the line L2 is greater than approximately 1.0 volts. Until such a pulse arrives, transistors Q1 and Q2 are open, resistors R5 and R6 effectively pull their bases to the same potential as their emitters. It is during this period that capacitors C2 and C3 are charged in parallel. Upon arrival of a trigger pulse on line L2 greater than approximately 1.0 volts, the output collectors of comparators AC1, AC2 are grounded, energizing transistors Q1 and Q2 by emitter base bias applied respectively through resistors R3 and R4. Subsequent release of the high state of line L2 then restores transistors Q1 and Q2 to an open condition, allowing the charging process to begin again. Capacitor Cl is connected across resistor R2 for noise suppression purposes, and to suppress the effects of contact bounce during closure of switch 4. The resulting light output pulse from diode 14 is focused by lens 16 (FIG. 1) to form a narrow interrogation cone of light of semiapex angle of the order of 4 degrees, a region generally well confined to the central portion of the ordinary 35 mm format when used in conjunction with a lens of focal length. FIG. 3 shows the circuit elements corresponding to the detector unit 26, latching comparator 28, and solenoid brake 44 of FIG. 1. As previously discussed, the present disclosure is oriented towards control of the focusing distance of a two-position lens positioned initially preferably at the hyperfocal position of the objective lens at its maximum aperture, the lens being thereafter released to be driven towards a short-focus position. This is most economically achieved in the present invention by configuring a solenoid brake (not shown) which normally prevents such motion from the far-focus position so long as solenoid S is energized. De-energizing this solenoid S releases this latching condition and allows the lens to be driven towards and arrested at the short-focus position. This occurs when transistor Q4 receives a high state at the base thereof indicative of strong light reception at diode 24. In more detail, the photosensing diode 24 receives light from lens 22 (FIG. 1), the diode being type VTP3310L made by VACTEC Corporation of St. Louis, Mo. U.S.A. and having an effective sensing area of approximately 1.03 mm 2 . The diode 24 and lens 22 are disposed so as to sense a central generally conical region of the viewing field of approximately 4 degrees apex semiangle, thereby receiving from a generally centrally located object in the field a return pulse of light. The optical system which excites diode 24 is preferably provided with an infrared-passing filter to screen out visible light insofar as is possible. This reduces the ambient excitation of diode 24 and provides for an increased range of photoresponse. The diode 24 is operated in the current mode and generates a current directly proportional to the infrared light striking it. Capacitor coupling by capacitor C5 prevents the input of transistor Q3 from seeing the static type infrared signal that exists in some environments, e.g. bright daylight and strong fluorescent lighting. Such ambient signals can overload the amplifier because of its high gain, thereby desensitizing the system with respect to the pulse signals that are to be measured. Coupling capacitor C5 and other capacitors are used to set the overall low frequency cutoff point for the amplifier. The amplifier, consisting of stages Q3 and Q4, is designed to have little sensitivity to signals below 1.5 kHz. This is important so that the amplifier can ignore the 120 Hz. infra-red flicker noise from 60 Hz. fluorescent lighting. Moreover, this low frequency cutoff combined with a high frequency cutoff of approximately 2.5 kHz. forms a band-pass response 1 kHz. wide, which improves the signal to noise ratio of the amplifier overall. Each of the two amplifier stages based upon transistors Q3 and Q4 has the same topology with slightly different component values to accommodate differences in operating point and impedance levels. Both stages use voltage mode feedback to stabilize the characteristics of the amplifier with respect to transistor variations. This form of feedback is chosen because the resulting amplifier then operates with the low power supply voltages that are present in the camera. Considering the first stage based upon transistor Q3 in more detail, the pulse developed across the diode 24 is applied to the base of transistor Q3. The collector output voltage developed across pull-up resistor R14 is connected to the next stage through capacitor C7, capacitor C6 serving to roll off the high frequency response. A frequency-dependent feedback voltage is delivered from the collector of transistor Q3 to the base thereof through the series resistive network R13, R12, R11. Capacitor C12 is connected to the junctures of resistors R12 and R13, and serves to reduce the amount of inverse feedback above a given frequency, thereby setting the low frequency response of this particular stage. The effect of this network is to make the a.c. load impedance presented to diode 24 to be about 2.8 kilohms. This renders the output of diode 24 to be generally linear with received light intensity thereby facilitating accurate range determination. The stage based upon transistor Q4 is, as previously mentioned, configured in a substantially identical way, again inserting high and low frequency rolloff in the same manner. It will be noted in particular that a strong light pulse on diode 24 will result in positive drive (high) to the base of transistor Q3, which in turn results in a low drive condition to the base of transistor Q4, again resulting in a high condition at the collector thereof to be relayed to the inverting terminal of amplitude comparator AC3. The output signal state of comparator AC3 governs whether or not solenoid S will be energized, and thus determines whether the lens is to be held immobile or moved to the near-focus position. The triggering threshold of comparator AC3 is set by the resistive divider R20, R22. Resistor R22 is a variable resistor, variation of this element setting the reference voltage derived from the 2.0 volt regulated supply to be provided to the inverting terminal of amplitude comparator AC3. In the absence of a strong light pulse sensing at diode 24, no signal will be applied to the noninverting terminal of comparator AC3, as a result of which the last-stage collector connected to the output terminal thereof will be grounded, resulting in a low state delivered to the negative terminal of the latching comparator circuit based on amplitude comparator AC4. A strong light signal, on the other hand, opens the output stage collector of comparator AC3, allowing the inverting input terminal of comparator AC4 to be pulled high. Comparator AC4 is configured as a set-reset latch. It will be recalled that on power-up the momentary closure of switch 6 (FIG. 1) and the virtually immediate release thereof placed a high-low transition on line L2. This has the effect of resetting amplitude comparator AC4 to the low-light condition, i.e. the output collector is turned off, and will not be driven low (closed) until a high state, corresponding to a bright illumination signal condition is received at the noninverting input of comparator AC4. This is accomplished by placing transistor Q6 in an on condition when line L2 goes high, thereby effectively grounding the lower end of resistor R29, and latching the inverting input terminal of amplitude comparator AC4 in a high state by positive feedback derived from the voltage divider R27, R28. This condition is maintained after line L2 goes low, and the comparator AC4 is thus held in a reset condition until a positive (high) pulse is received from comparator AC3. It will also be noted that, since the shutter button 3 is released after every subsequent exposure, an automatic clearing reset operation is carried at comparator AC4 in preparation for the next exposure. Thus, on initial power-up, comparator AC4 will be latched with its output collector open, placing a high state on the base of transistor Q5 through resistor R6, thus energizing the solenoid S to prevent movement of the objective lens from the far-focus position. If, however, a sufficiently bright flash is received by the diode 24, then a high state will appear at the noninverting input of comparator AC3, resulting in a high state at the inverting input of comparator AC4, causing closure of the output stage collector, effectively grounding the driven end of resistor R26, simultaneously removing drive to transistor Q25, and hence to the solenoid S. This allows the free movement of the objective lens to the near-focus position. The system described hereinabove functions reliably in detecting objects as far as 15 feet from the objective lens, when used in conjunction with range finding lenses 16, 22 having an approximate focal length of 19 mm and diameter of 10 mm. The use of a single pulse system providing the range information by means of reflected amplitude only, and not requiring the use of relatively expensive triangulation detectors markedly reduces manufacture of the price of such units, and contributes materially to system simplicity. It will also be recognized that the system described may equally well be reconfigured with additional amplitude comparators to provide, for example, an intermediate focus setting by using system S described with reference to FIG. 1. Finally, it should be recognized that the principles of the present invention may readily be adapted to be incorporated into cameras having additional features not recited herein. Thus, for example, the power supply 10 (FIG. 1) may be of the time-out type which is brought into operation to remain active for a period of five minutes or so in response to momentary closure of switch S5. For convenience, an additional pair of early-closure contacts may be associated with the push button switch 8 and connected in parallel so that a light tap on the pushbutton 3 will restore the power supply to an active condition. Additionally, provision may readily be made by means that will be apparent to those skilled in the art to incorporate a pre-focus feature by appropriate switching whereby the camera may be pointed at the object on which the camera is to be focused, the shutter button 3 partially depressed to trigger the ranging circuitry to set the latching comparator AC4, the camera thus pointed to place the focused object off center with respect to the scene to be photographed, after which time further depression of the shutter button the shutter motor 40 and shutter actuator 46.
An infrared ranging system for a battery-powered camera uses a light-emitting diode and associated pulse circuitry for producing a single ranging flash concentrated by a lens into a narrow cone of light generally centrally located in the field of view. The diode is powered by a capacitor bank charged in parallel and discharged in series to provide the necessary current pulse to the diode from a 2.0 volt system. The received pulse is concentrated on a photosensing diode by means of an infrared-passing lens to produce a voltage pulse related to amplitude of the reflected light, and hence to the range to a centrally located object in the field, this pulse being processed to set the state of one or more range-indicating latch circuits. The state of the latch circuits is used to govern the final setting of a driven adjustable focus lens. The system is equally applicable to setting the camera aperture in flash mode wherein the aperture is a range-dependent function.
Briefly describe the main idea outlined in the provided context.
[ "TECHNICAL FIELD The technical field of the invention is automatic electrically operated cameras, and in particular range sensing systems for battery-powered cameras.", "BACKGROUND ART In battery-powered cameras there have long been known a variety of range sensing systems for automatically setting the focus of the lens to correspond to the distance of an object centrally located in the field of view, or alternatively for adjusting the aperture in flash mode where the aperture setting is also a range-dependent parameter.", "Such systems have employed ultrasonic or infra-red signals directed at the object of interest.", "The infra-red signal sources were generally gas filled flash lamps.", "In some cases, the same flash lamp used for illuminating the subject is also used in a pre-flash mode to first generate the range determining signal.", "In other cameras, a separate gas flash lamp is used for range determining purposes.", "In either case, the distance of the object from the camera is determined by measuring the amplitude of the reflected signal.", "The use of gas filled flash lamps as the source of infra-red energy is relatively costly as compared, for example, to the cost of using infra-red light emitting diodes;", "however, the intensity of the energy directed by such diode sources has heretofore been of such low intensity that it is believed that only a triangulation means using relatively expensive circuitry for determining range was thought to be practical.", "An example of a ranging system which uses a triangulation based measuring system is currently marketed by Hamamatsu Photonics of Hamamatsu City, Japan, and is described in their technical data sheet entitled "Autofocus Devices"", "dated March, 1984.", "The system described therein is based upon an optical triangulation system wherein a light-emitting diode is powered at relatively low power and focused into a beam directed at an object centrally located in the scene to be photographed.", "A position sensing diode is disposed to receive reflected light focused thereon by a lens, the position of the spot on the diode being used to derive a difference signal used to govern signal processing circuitry so that the output signal used to govern the relevant camera parameter is related to the range of the object.", "The photosensing diode is a three-terminal device in the form of a P-I-N diode having a common electrode on the rear face thereof and a pair of output electrodes disposed on the light-receiving face on either side of a central sensing region.", "The position sensing diode is operated in biased photovoltaic mode, and appears to provide a voltage difference at the two output terminals according to the position of the incident light spot with respect to the center of symmetry of the structure.", "The signal processing circuitry associated with such a device appears to be quite complex, involving a pair of signal processing circuits.", "Each signal processing circuit in turn feeds a distance calculation circuit, the output of which is fed to a sample-and-hold or alternatively to an analog-to-digital converter to govern the adjustment of the relevant camera parameter.", "The circuitry necessary to accomplish this is quite expensive, and the photosensing diode itself, being a three-terminal device, is expensive because of the number of terminals alone, as well as because of the highly specialized nature of the device itself.", "Additionally, the light emitting diode appears to be driven at a relatively low power level of 10 milliwatts, which would raise a severe signal-to-noise problem.", "This in all likelihood requires a continuous modulation of the diode driver power, coupled with some form of synchronous detection in the signal processing circuitry;", "however, no such feature is shown explicitly in the aforementioned Data Sheet.", "There remains a need in the case of cameras for the intermediate price market for an inexpensive infra-red range sensing system which does not have the complexity, and hence the expense, of the systems of the type described hereinabove.", "Moreover, as applied to cameras having two-position lenses wherein the lens is set to either a far-focus position placing the distant edge of the field at infinity (the hyperfocal distance) or to a near-focus setting substantially closer than the hyperfocal setting, a simple range finding system capable of providing reliable ranging information for objects out to no more than 15 feet or so would be more than adequate, provided that it can be accomplished at minimum cost.", "To the applicant's knowledge, no such system has yet been provided.", "SUMMARY OF THE INVENTION According to a feature of the invention, a camera range-finding system employs an infra-red light-emitting diode operated in pulse mode to produce a single relatively high amplitude pulse of infra-red light confined by directing means, preferably in the form of a lens, to define a relatively narrow cone of illumination projected into a generally centrally located region of the field of view.", "An infra-red sensing diode receives the reflected light from a second directing means, again preferably in the form of a lens, which focuses light reflected from an object in this centrally located region onto a detecting diode to produce an excitation signal having an amplitude which increases generally according to the amount of light received by the second directing means.", "In the preferred form of the invention, the amplitude of this signal is used to set one or more latching comparators which govern the terminal position of a lens drive system, or alternatively an aperture drive system, to adjust these image-affecting parameters according to the strength of the received radiation, and hence according to the distance to the object.", "According to specific features of the invention, the light emitting diode is driven in a short pulsed mode wherein a short current pulse is applied to excite the diode, the pulse current being substantially greater than the maximum steady-state rated current of the diode, and in the preferred embodiment, being at least an order of magnitude greater.", "According to a further specific feature of the invention, the light-emitting diode is provided with its excitation current from a bank of two or more capacitors which are charged in parallel from a regulated battery voltage of 2.0 volts and discharged in series, thereby boosting the excitation voltage and allowing diodes of the gallium arsenide family having relatively high excitation voltages to be successfully employed even if the source 3.0 volt battery becomes weak.", "The resulting ranging system is reliable up to ranges of at least 15 feet, and thus provides the desired inexpensive control of the camera.", "Other features and advantages of the invention will become apparent upon making reference to the specification and claims to follow and the drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block schematic diagram of the principal elements of an electrically operated camera deriving range information from an emitted and reflected light pulse using the amplitude of the reflected pulse to adjust either lens focus or lens aperture.", "FIG. 2 is a schematic diagram of a circuit for producing electrical pulses to energize a light emitting diode.", "FIG. 3 is a pulse detection circuit for converting a received light pulse to a control signal used to control a camera setting.", "DETAILED DESCRIPTION While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail a preferred embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention, and is not intended to limit the broad aspect of the invention to the embodiment illustrated.", "FIG. 1 is a block schematic diagram showing in general form the principal aspects of the present invention as applied to adjusting an image-affecting parameter of a camera, i.e., the focus setting of the lens or the aperture setting, according to the distance to the object to be photographed.", "The camera aperture setting, is, as is well known, a range-dependent variable when the camera is operated in flash mode.", "In the description to follow concerning FIG. 1, discussion will be directed toward the provision of three or more parameter settings, whereas the subsequent discussion of the circuitry implementing the concepts of the present invention as shown in FIGS. 2 and 3 will be oriented towards a simpler two-position focusing system based upon similar principles.", "Considering FIG. 1 in more detail, power is applied from a battery to a power supply 10.", "A lens cover slide 7 is coupled to a pair of switches 5, 6 which are actuated responsively to moving the slide to uncover the lens preparatory to using the camera.", "Closure of switch 5 brings the power supply to an active condition, immediately supplying regulated voltages of 2.0 and 0.5 volts, and an unregulated voltage of 3.0 volts to power the various elements of the system.", "Switch 6 is a momentary contact switch which momentarily closes after the closure of switch 5 and after the power supply output voltages have been established, thereafter breaking contact.", "During this interval 3.0 volts are momentarily supplied to control line L2, after which time this voltage reverts to zero.", "As will subsequently be discussed, the reversion of line L2 to a low state is used to stabilize various aspects of the circuit into a proper configuration for signal processing.", "Subsequent actuation of a manually operated shutter release button 3 again raises control line L2 to a high state to trigger a pulse unit 12 to provide a short pulse of current to a light-emitting diode 14.", "Light from the infrared light-emitting diode 14 is focused into a relatively narrow beam 18 illuminating a central region of the scene of interest.", "Light 20 reflected from an object generally centrally located in the scene is received by lens 22 and focused on a light-sensing diode 24.", "The excitation received by diode 24 thus varies with the distance to the object from which the outgoing beam 18 is reflected.", "This excitation signal is processed by a detector unit 26 to provide on output line L4 a signal varying in amplitude with the magnitude of excitation received by the light-sensing diode 24.", "The remainder of the system is best understood with reference to U.S. Pat. No. 4,473,285 issued to Winter, wherein there is described a system generally similar to that shown in FIG. 1. A plurality of comparators 28, 30 (and more if desired) are provided, each comparator being of the latching type and having a different triggering threshold.", "The system shown in FIG. 1 is particularized to a three-range system.", "Under extremely weak conditions, the signal on line L4 will be insufficient to trigger either of the comparators 28, 30.", "This corresponds to objects at very far distances, requiring for example, the maximum-range focus setting of the camera lens.", "If the object is at an intermediate distance, then latching comparator 30 will trigger, but latching comparator 28 will not.", "For extremely close objects, both of the comparators 28, 30 will be triggered.", "The respective comparator outputs are placed on lines L6 and L8 respectively.", "As described in the Winter patent, an electromechanical adjustment system 41 includes a rotary contact 38 having, in this case, three contacting pads 32, 34, 36 is driven into scanning rotation by a motor 40 upon total depression of the shutter button 3.", "This motor is typically of the spring-driven variety, being energized and cocked during the film advance process.", "Full operation of the shutter release button 3 releases the rotor 38 to sequentially contact the pads 32, 34, 36 in the order shown.", "As the rotor 38 contacts each of the pads 32, 34, 36 serially, the voltage supplied thereto from the latching comparators 28, 30 is sensed by a controller 42.", "In the event that a close object has caused the amplitude on line L4 to be quite high, both comparators 28, 30 will be latched to a presence-sensing state, as a result of which the rotor 38, upon contacting pad 32 will immediately relay this condition to the controller 42, which in turn operates a solenoid brake or latch 44, which acts to freeze the rotation of the rotor 38 on pad 32.", "The photographic objective lens 41 is synchronously coupled to the rotation of rotor 38 via the rotation of the motor 40 to be driven thereby through a range of focus settings.", "Such a system is fully disclosed in the above-referenced Winter patent.", "Thus, the solenoid brake 44 freezes the operation of the lens focusing system upon contacting the close-distance pad 32, establishing the focusing of the lens 41 for a close object.", "In the event that the object is at an intermediate range capable of triggering only comparator 30, then the rotor 38 will continue its rotation until encountering the presence-indicating signal present on pad 34, thus terminating the motion of the lens at 41 the intermediate-focusing position.", "Finally, if neither comparator has been triggered, indicating a very distant object, then rotation continues to the extreme possible travel of the rotor 38 (and hence the lens 41) to terminate on pad 36, which corresponds to a mechanical limit stop in the focusing system of the lens 41.", "The lens 41 is now set for farthest focus.", "Responsively to final total depression of the shutter release button 3, a shutter actuator 46 actuates the shutter through an exposure cycle.", "Alternatively, a similar synchronously driven rotor may be employed in conjunction with a lens aperture control system for flash mode operation, such a system also being described in the above-referenced Winter patent.", "FIG. 2 shows the circuit which produces a single pulse of infrared light from the light-emitting diode 14 responsively to the voltage pulse received via line L2 from the shutter release switch 8.", "Considering the pulse unit of FIG. 2 in more detail, the purpose of this unit is to charge diode energizing capacitors C2, C3 to essentially the full regulated 2.0 volts, and thereafter to deliver this charge to the light-emitting diode 14 as a short pulse responsively to the triggering pulse on line L2.", "The light-emitting diode 14 in the present embodiment is the infrared type TLN115 made by Toshiba.", "This diode 14 is operated in a pulse mode wherein a current of one ampere, the recommended maximum pulse current, is supplied initially to the diode to provide a current pulse decaying to the diode threshold turn-on value in approximately 90 microseconds.", "This pulsed operation is to be compared with the recommended maximum continuous operating current 100 milliamperes for such a unit.", "Being of the gallium arsenide family, this diode 14 requires a minimum of 2.2 volts in the forward direction for light emission.", "The present design is oriented towards use of a battery of 3.0 volts regulated down to 2.0 volts to provide for uniform excitation to the light-emitting diode 14.", "As will next be discussed, proper energizing current for the light-emitting diode 14 is achieved by charging the two discharge capacitors C2, C3 in parallel from the regulated 2.0 volt supply and thereafter discharging them in series through the diode.", "The foregoing is accomplished by holding transistors Q1 and Q2 open in charging mode, whereafter they are both turned on to connect the capacitors C2, C3 in series to discharge them through the diode 14.", "In more detail, with transistors Q1 and Q2 off, then capacitor C3 is charged through resistors R8 and R10 from the 2.0 volt supply, placing the negative terminal of this capacitor at ground.", "Capacitor C2 is charged at the positive terminal thereof through resistor R9 from the positive 2.0 volt supply, and has the negative terminal thereof grounded through resistor R7.", "Transistors Q1 and Q2 are of the low saturation voltage type.", "When transistors Q1 and Q2 are turned on the current into the diode 14 flows from capacitor C3 through transistor Q1, through capacitor C2, (now connected in series with capacitor C3), and through transistor Q2.", "Thus, although capacitor C2 and C3 were charged in parallel from the 2.0 volt supply in charge mode, in discharge mode they are effectively connected in series with the diode 14.", "Simultaneous triggering of transistors Q1 and Q2 is achieved by simultaneous operation of the amplitude comparators AC1 and AC2.", "Each comparator has its noninverting input terminal connected to regulated 0.5 volts, and the inverting input terminal connected to the battery voltage pulse provided on line L2 and attenuated to approximately 1.0 volts or thereabouts by the attenuating pair R1, R2.", "Before the arrival of the trigger pulse, the 0.5 volt reference level applied to the noninverting input of the comparators AC1 and AC2 acts to produce an open circuit at the output thereof.", "These comparators AC1 and AC2 are of the open-collector type, their output stage collectors being essentially grounded when a positive signal greater than the 0.5 volt reference is applied to their inverting inputs.", "This will occur whenever the voltage pulse arriving on the line L2 is greater than approximately 1.0 volts.", "Until such a pulse arrives, transistors Q1 and Q2 are open, resistors R5 and R6 effectively pull their bases to the same potential as their emitters.", "It is during this period that capacitors C2 and C3 are charged in parallel.", "Upon arrival of a trigger pulse on line L2 greater than approximately 1.0 volts, the output collectors of comparators AC1, AC2 are grounded, energizing transistors Q1 and Q2 by emitter base bias applied respectively through resistors R3 and R4.", "Subsequent release of the high state of line L2 then restores transistors Q1 and Q2 to an open condition, allowing the charging process to begin again.", "Capacitor Cl is connected across resistor R2 for noise suppression purposes, and to suppress the effects of contact bounce during closure of switch 4.", "The resulting light output pulse from diode 14 is focused by lens 16 (FIG.", "1) to form a narrow interrogation cone of light of semiapex angle of the order of 4 degrees, a region generally well confined to the central portion of the ordinary 35 mm format when used in conjunction with a lens of focal length.", "FIG. 3 shows the circuit elements corresponding to the detector unit 26, latching comparator 28, and solenoid brake 44 of FIG. 1. As previously discussed, the present disclosure is oriented towards control of the focusing distance of a two-position lens positioned initially preferably at the hyperfocal position of the objective lens at its maximum aperture, the lens being thereafter released to be driven towards a short-focus position.", "This is most economically achieved in the present invention by configuring a solenoid brake (not shown) which normally prevents such motion from the far-focus position so long as solenoid S is energized.", "De-energizing this solenoid S releases this latching condition and allows the lens to be driven towards and arrested at the short-focus position.", "This occurs when transistor Q4 receives a high state at the base thereof indicative of strong light reception at diode 24.", "In more detail, the photosensing diode 24 receives light from lens 22 (FIG.", "1), the diode being type VTP3310L made by VACTEC Corporation of St. Louis, Mo.", "U.S.A. and having an effective sensing area of approximately 1.03 mm 2 .", "The diode 24 and lens 22 are disposed so as to sense a central generally conical region of the viewing field of approximately 4 degrees apex semiangle, thereby receiving from a generally centrally located object in the field a return pulse of light.", "The optical system which excites diode 24 is preferably provided with an infrared-passing filter to screen out visible light insofar as is possible.", "This reduces the ambient excitation of diode 24 and provides for an increased range of photoresponse.", "The diode 24 is operated in the current mode and generates a current directly proportional to the infrared light striking it.", "Capacitor coupling by capacitor C5 prevents the input of transistor Q3 from seeing the static type infrared signal that exists in some environments, e.g. bright daylight and strong fluorescent lighting.", "Such ambient signals can overload the amplifier because of its high gain, thereby desensitizing the system with respect to the pulse signals that are to be measured.", "Coupling capacitor C5 and other capacitors are used to set the overall low frequency cutoff point for the amplifier.", "The amplifier, consisting of stages Q3 and Q4, is designed to have little sensitivity to signals below 1.5 kHz.", "This is important so that the amplifier can ignore the 120 Hz.", "infra-red flicker noise from 60 Hz.", "fluorescent lighting.", "Moreover, this low frequency cutoff combined with a high frequency cutoff of approximately 2.5 kHz.", "forms a band-pass response 1 kHz.", "wide, which improves the signal to noise ratio of the amplifier overall.", "Each of the two amplifier stages based upon transistors Q3 and Q4 has the same topology with slightly different component values to accommodate differences in operating point and impedance levels.", "Both stages use voltage mode feedback to stabilize the characteristics of the amplifier with respect to transistor variations.", "This form of feedback is chosen because the resulting amplifier then operates with the low power supply voltages that are present in the camera.", "Considering the first stage based upon transistor Q3 in more detail, the pulse developed across the diode 24 is applied to the base of transistor Q3.", "The collector output voltage developed across pull-up resistor R14 is connected to the next stage through capacitor C7, capacitor C6 serving to roll off the high frequency response.", "A frequency-dependent feedback voltage is delivered from the collector of transistor Q3 to the base thereof through the series resistive network R13, R12, R11.", "Capacitor C12 is connected to the junctures of resistors R12 and R13, and serves to reduce the amount of inverse feedback above a given frequency, thereby setting the low frequency response of this particular stage.", "The effect of this network is to make the a.c. load impedance presented to diode 24 to be about 2.8 kilohms.", "This renders the output of diode 24 to be generally linear with received light intensity thereby facilitating accurate range determination.", "The stage based upon transistor Q4 is, as previously mentioned, configured in a substantially identical way, again inserting high and low frequency rolloff in the same manner.", "It will be noted in particular that a strong light pulse on diode 24 will result in positive drive (high) to the base of transistor Q3, which in turn results in a low drive condition to the base of transistor Q4, again resulting in a high condition at the collector thereof to be relayed to the inverting terminal of amplitude comparator AC3.", "The output signal state of comparator AC3 governs whether or not solenoid S will be energized, and thus determines whether the lens is to be held immobile or moved to the near-focus position.", "The triggering threshold of comparator AC3 is set by the resistive divider R20, R22.", "Resistor R22 is a variable resistor, variation of this element setting the reference voltage derived from the 2.0 volt regulated supply to be provided to the inverting terminal of amplitude comparator AC3.", "In the absence of a strong light pulse sensing at diode 24, no signal will be applied to the noninverting terminal of comparator AC3, as a result of which the last-stage collector connected to the output terminal thereof will be grounded, resulting in a low state delivered to the negative terminal of the latching comparator circuit based on amplitude comparator AC4.", "A strong light signal, on the other hand, opens the output stage collector of comparator AC3, allowing the inverting input terminal of comparator AC4 to be pulled high.", "Comparator AC4 is configured as a set-reset latch.", "It will be recalled that on power-up the momentary closure of switch 6 (FIG.", "1) and the virtually immediate release thereof placed a high-low transition on line L2.", "This has the effect of resetting amplitude comparator AC4 to the low-light condition, i.e. the output collector is turned off, and will not be driven low (closed) until a high state, corresponding to a bright illumination signal condition is received at the noninverting input of comparator AC4.", "This is accomplished by placing transistor Q6 in an on condition when line L2 goes high, thereby effectively grounding the lower end of resistor R29, and latching the inverting input terminal of amplitude comparator AC4 in a high state by positive feedback derived from the voltage divider R27, R28.", "This condition is maintained after line L2 goes low, and the comparator AC4 is thus held in a reset condition until a positive (high) pulse is received from comparator AC3.", "It will also be noted that, since the shutter button 3 is released after every subsequent exposure, an automatic clearing reset operation is carried at comparator AC4 in preparation for the next exposure.", "Thus, on initial power-up, comparator AC4 will be latched with its output collector open, placing a high state on the base of transistor Q5 through resistor R6, thus energizing the solenoid S to prevent movement of the objective lens from the far-focus position.", "If, however, a sufficiently bright flash is received by the diode 24, then a high state will appear at the noninverting input of comparator AC3, resulting in a high state at the inverting input of comparator AC4, causing closure of the output stage collector, effectively grounding the driven end of resistor R26, simultaneously removing drive to transistor Q25, and hence to the solenoid S. This allows the free movement of the objective lens to the near-focus position.", "The system described hereinabove functions reliably in detecting objects as far as 15 feet from the objective lens, when used in conjunction with range finding lenses 16, 22 having an approximate focal length of 19 mm and diameter of 10 mm.", "The use of a single pulse system providing the range information by means of reflected amplitude only, and not requiring the use of relatively expensive triangulation detectors markedly reduces manufacture of the price of such units, and contributes materially to system simplicity.", "It will also be recognized that the system described may equally well be reconfigured with additional amplitude comparators to provide, for example, an intermediate focus setting by using system S described with reference to FIG. 1. Finally, it should be recognized that the principles of the present invention may readily be adapted to be incorporated into cameras having additional features not recited herein.", "Thus, for example, the power supply 10 (FIG.", "1) may be of the time-out type which is brought into operation to remain active for a period of five minutes or so in response to momentary closure of switch S5.", "For convenience, an additional pair of early-closure contacts may be associated with the push button switch 8 and connected in parallel so that a light tap on the pushbutton 3 will restore the power supply to an active condition.", "Additionally, provision may readily be made by means that will be apparent to those skilled in the art to incorporate a pre-focus feature by appropriate switching whereby the camera may be pointed at the object on which the camera is to be focused, the shutter button 3 partially depressed to trigger the ranging circuitry to set the latching comparator AC4, the camera thus pointed to place the focused object off center with respect to the scene to be photographed, after which time further depression of the shutter button the shutter motor 40 and shutter actuator 46." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a divisional application of U.S. patent application Ser. No. 12/143,492, filed Jun. 20, 2008, which claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 60/946,487, filed Jun. 27, 2007. The disclosure of said applications are hereby incorporated herein by reference. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable. BACKGROUND 1. Field of the Invention This invention relates generally to the field of chemical reactions. More specifically, the invention relates to methods of making chlorohydrins incorporating high shear mixing. 2. Background of the Invention Chlorohydrins are useful as intermediates in producing various compounds. For example, propylene chlorohydrin and butylene chlorohydrin are used in producing propylene oxide and butylene oxide, respectively. Various processes are known for the production of chlorohydrins. For example, olefin chlorohydrins are typically prepared by reacting an olefin with chlorine in the presence of water. This process is believed to occur by means of an intermediate cyclic chloronium ion which reacts with the water to form an olefin chlorohydrin. The olefin may be one containing from 8 to about 30 carbon atoms. However, the process also concurrently forms undesirable dichloride byproducts when aqueous chloride ions react with the cyclic chloronium ions. Significant yield losses are typically suffered and the byproducts must be separated from the desired olefin chlorohydrin, an operation that adds to the cost of making the chlorohydrin. Alternatively, the process described above may include a water immiscible solvent. Therefore, the reaction would entail the addition of hypochlorous acid to a long chain olefin in the presence of water in a water immiscible solvent. Suitable solvents include decane, chloroform and petroleum ether. Other processes for producing chlorohydrins involve reacting olefins with hypochlorous acid, wherein the process requires preliminarily acidifying the olefin with gaseous hydrochloric acid and carrying out the process at a pH of between 2 to 7, and preferably between 5 to 6. Another method of making chlorohydrins involves preparing hypochlorous acid by reacting chlorine and water in the presence of alkaline earth metal hydroxides (maintaining a pH below 7.0), then, reacting the hypochlorous acid mixture with a vinyl group-containing compound. Alternatively the preparation of chlorohydrin may be achieved by reaction of olephins with trichloroisocyanuric acid in alcohols, acetic acid or aqueous acetone. Various other methods of forming chlorohydrins are also well known such as reacting olefins with t-butyl hypochlorite or hypochlorous acid substantially free of chloride ions. However, these methods typically either result in the production of numerous byproducts or require various, costly processing steps or long reaction times, thus hindering the commercial viability of the methods. For these reasons, there remains a need for a process for producing chlorohydrin that is effective and results in high yields of the desired product. In light of the above, it is apparent that research has been focused on different reaction pathways in producing chlorohydrins. However, none of these methods discuss improving the solubility and mass transfer of the reactants through improved mixing. Consequently, there is a need for accelerated methods for making chlorohydrins by improving the mixing of olefins into the liquid chlorinating phase. BRIEF SUMMARY Methods and systems for the preparation of chlorohydrins are described herein. The methods and systems incorporate the novel use of a high shear device to promote dispersion and solubility of olefins into the chlorinating phase. The high shear device may allow for lower reaction temperatures and pressures and may also reduce chlorination time. Further advantages and aspects of the disclosed methods and system are described below. In an embodiment, a method of making a chlorohydrin comprises contacting an olefin with a chlorinating agent. In an embodiment the liquid is an aqueous solution, a hypochlorous acid solution, an aqueous hypochlorite solution or chlorine dissolved in H 2 O and the gas comprised of an olefin which is reactive under the conditions of mixing with one or more components of the liquid to form reaction products including the desired olefin chlorohydrin product. The method also comprises flowing the olefin and the chorinating agent through a high shear device so as to form dispersion with bubbles less than about 1 μm and form a chlorohydrin. In an embodiment, a system for making a chlorohydrin comprises at least one high shear device configured for chlorinating an olefin. The high shear device comprises a rotor and a stator. The rotor and the stator are separated by a shear gap in the range of from about 0.02 mm to about 5 mm. The shear gap is a minimum distance between the rotor and the stator. The high shear device is capable of producing a tip speed of the at least one rotor of greater than about 23 m/s (4,500 ft/min). In addition, the system comprises a pump configured for delivering a liquid stream comprising liquid phase to the high shear device. The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which: FIG. 1 illustrates a general flow diagram of an embodiment of a process of making chlorohydrins using a high shear device. FIG. 2 illustrates a longitudinal cross-section view of a multi-stage high shear device, as employed in an embodiment of the system of FIG. 1 . NOTATION AND NOMENCLATURE Certain terms are used throughout the following description and claims to refer to particular system components. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ”. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The disclosed methods and systems for the chlorination of an olefin employ a high shear mechanical device to provide rapid contact and mixing of the olefin gas and chlorinating agent in a controlled environment in the reactor/mixer device. The term “olefin gas” as used herein includes both substantially olefin gas as well as gaseous mixtures containing olefin. In particular, embodiments of the systems and methods may be used in the production of chlorohydrins from the chlorination of olefins in water. Preferably, the method comprises a heterogeneous phase reaction of a chlorine species in liquid phase with an olefin gas. The high shear device reduces the mass transfer limitations on the reaction and thus increases the overall reaction rate. Chemical reactions involving liquids, gases and solids rely on the laws of kinetics that involve time, temperature, and pressure to define the rate of reactions. In cases where it is desirable to react two (or more) raw materials of different phases (e.g. solid and liquid; liquid and gas; solid, liquid and gas), one of the limiting factors in controlling the rate of reaction involves the contact time of the reactants. As used herein, “multi-phase” refers to a reaction involving reactions with two or more different phases. In the case of heterogeneously catalyzed reactions there is the additional rate limiting factor of having the reacted products removed from the surface of the catalyst to enable the catalyst to catalyze further reactants. The chlorination of olefins to produce chlorohydrin is a multiphase reaction. During the multiphase reaction, the phases separate spontaneously. The presently disclosed method and system whereby the two phases are intimately mixed to form an emulsion enhances contact surface between the reaction components, thus enhancing the reaction. The pH of the reaction may have a direct impact on the reaction rate and thus the olefin conversion. The pH employed may vary depending on the chlorines present in the aqueous phase. The maximum pH is about 8. When the aqueous phase contains free chloride ions and molecular chlorine, the pH should not be below 4.5. When an essentially chloride and chlorine-free aqueous solution is employed herein, the pH can range as low as 1. The process described here in comprises an aqueous phase having a pH ranging from about 2 to about 8. Chlorohydrin yield is particularly good in low olefin conversion when an aqueous phase of pH of about 6 is employed. In conventional reactors, contact time for the reactants and/or catalyst is often controlled by mixing which provides contact with two or more reactants involved in a chemical reaction. Embodiments of the disclosed method comprise an external high shear device to decrease mass transfer limitations and thereby more closely approach kinetic limitations. When reaction rates are accelerated, residence times may be decreased, thereby increasing obtainable throughput. Alternatively, where the current yield is acceptable, decreasing the required residence time allows for the use of lower temperatures and/or pressures than conventional processes. Furthermore, in homogeneous reactions, the disclosed process could be used to provide for uniform temperature distribution within the reactor thereby minimizing potential side reactions. System for Production of Chlorohydrin. A high shear chlorohydrin production system will now be described in relation to FIG. 1 , which is a process flow diagram of an embodiment of a high shear system (HSS) 100 for the production of chlorohydrin via reacting a chlorinating agent with olefins in a gas-liquid phase reaction. The basic components of a representative system include external high shear device (HSD) 140 , vessel 110 , pump 105 and fluidized or fixed bed 142 . As shown in FIG. 1 , the high shear device is located external to vessel/reactor 110 . Each of these components is further described in more detail below. Line 121 is connected to pump 105 for introducing reactant. Line 113 connects pump 105 to HSD 140 , line 118 connects HSD 140 to fluidized or fixed bed 142 and line 119 connects bed to vessel 110 . Line 122 is connected to line 113 for introducing an oxygen-containing gas (e.g., O 2 or air). Line 117 is connected to vessel 110 for removal of unreacted vapor, and other reaction gases. High shear devices (HSDs) such as a high shear device, or high shear mill, are generally divided into classes based upon their ability to mix fluids. Mixing is the process of reducing the size of inhomogeneous species or particles within the fluid. One metric for the degree or thoroughness of mixing is the energy density per unit volume that the mixing device generates to disrupt the fluid particles. The classes are distinguished based on delivered energy density. There are three classes of industrial mixers having sufficient energy density to consistently produce mixtures or emulsions with particle or bubble sizes in the range of 0 to 50 microns. High shear mechanical devices include homogenizers as well as colloid mills. Homogenization valve systems are typically classified as high energy devices. Fluid to be processed is pumped under very high pressure through a narrow-gap valve into a lower pressure environment. The pressure gradients across the valve and the resulting turbulence and cavitations act to break-up any particles in the fluid. These valve systems are most commonly used in milk homogenization and can yield average particle size range from about 0.01 μm to about 1 μm. At the other end of the spectrum are high shear mixer systems classified as low energy devices. These systems usually have paddles or fluid rotors that turn at high speed in a reservoir of fluid to be processed, which in many of the more common applications is a food product. These systems are usually used when average particle, or bubble, sizes of greater than 20 microns are acceptable in the processed fluid. Between low energy-high shear mixers and homogenization valve systems, in terms of the mixing energy density delivered to the fluid, are colloid mills, which are classified as intermediate energy devices. The typical colloid mill configuration includes a conical or disk rotor that is separated from a complementary, liquid-cooled stator by a closely-controlled rotor-stator gap, which is maybe between 0.025 mm and 10.0 mm. Rotors are usually driven by an electric motor through a direct drive or belt mechanism. Many colloid mills, with proper adjustment, can achieve average particle, or bubble, sizes of about 0.01 μm to about 25 μm in the processed fluid. These capabilities render colloid mills appropriate for a variety of applications including colloid and oil/water-based emulsion processing such as that required for cosmetics, mayonnaise, silicone/silver amalgam formation, or roofing-tar mixing. An approximation of energy input into the fluid (kW/L/min) can be made by measuring the motor energy (kW) and fluid output (L/min). In embodiments, the energy expenditure of a high shear device is greater than 1000 W/m 3 . In embodiments, the energy expenditure is in the range of from about 3000 W/m 3 to about 7500 W/m 3 . The shear rate generated in a high shear device may be greater than 20,000 s −1 . In embodiments, the shear rate generated is in the range of from 20,000 s −1 to 100,000 s −1 . Tip speed is the velocity (m/sec) associated with the end of one or more revolving elements that is transmitting energy to the reactants. Tip speed, for a rotating element, is the circumferential distance traveled by the tip of the rotor per unit of time, and is generally defined by the equation V (m/sec)=π·D·n, where V is the tip speed, D is the diameter of the rotor, in meters, and n is the rotational speed of the rotor, in revolutions per second. Tip speed is thus a function of the rotor diameter and the rotation rate. Also, tip speed may be calculated by multiplying the circumferential distance transcribed by the rotor tip, 2πR, where R is the radius of the rotor (meters, for example) times the frequency of revolution (for example revolutions (meters, for example) times the frequency of revolution (for example revolutions per minute, rpm). For colloid mills, typical tip speeds are in excess of 23 m/sec (4500 ft/min) and can exceed 40 m/sec (7900 ft/min). For the purpose of the present disclosure the term ‘high shear’ refers to mechanical rotor-stator devices, such as mills or mixers, that are capable of tip speeds in excess of 5 m/sec (1000 ft/min) and require an external mechanically driven power device to drive energy into the stream of products to be reacted. A high shear device combines high tip speeds with a very small shear gap to produce significant friction on the material being processed. Accordingly, a local pressure in the range of about 1000 MPa (about 145,000 psi) to about 1050 MPa (152,300 psi) and elevated temperatures at the tip of the shear mixer are produced during operation. In certain embodiments, the local pressure is at least about 1034 MPa (about 150,000 psi). Referring now to FIG. 2 , there is presented a schematic diagram of a high shear device 200 . High shear device 200 comprises at least one rotor-stator combination. The rotor-stator combinations may also be known as generators 220 , 230 , 240 or stages without limitation. The high shear device 200 comprises at least two generators, and most preferably, the high shear device comprises at least three generators. The first generator 220 comprises rotor 222 and stator 227 . The second generator 230 comprises rotor 223 , and stator 228 ; the third generator comprises rotor 224 and stator 229 . For each generator 220 , 230 , 240 the rotor is rotatably driven by input 250 . The generators 220 , 230 , 240 rotate about axis 260 in rotational direction 265 . Stator 227 is fixably coupled to the high shear device wall 255 . The generators include gaps between the rotor and the stator. The first generator 220 comprises a first gap 225 ; the second generator 230 comprises a second gap 235 ; and the third generator 240 comprises a third gap 245 . The gaps 225 , 235 , 245 are between about 0.025 mm (0.01 in) and 10.0 mm (0.4 in) wide. Alternatively, the process comprises utilization of a high shear device 200 wherein the gaps 225 , 235 , 245 are between about 0.5 mm (0.02 in) and about 2.5 mm (0.1 in). In certain instances the gap is maintained at about 1.5 mm (0.06 in). Alternatively, the gaps 225 , 235 , 245 are different between generators 220 , 230 , 240 . In certain instances, the gap 225 for the first generator 220 is greater than about the gap 235 for the second generator 230 , which is greater than about the gap 245 for the third generator 240 . Additionally, the width of the gaps 225 , 235 , 245 may comprise a coarse, medium, fine, and super-fine characterization. Rotors 222 , 223 , and 224 and stators 227 , 228 , and 229 may be toothed designs. Each generator may comprise two or more sets of rotor-stator teeth, as known in the art. Rotors 222 , 223 , and 224 may comprise a number of rotor teeth circumferentially spaced about the circumference of each rotor. Stators 227 , 228 , and 229 may comprise a number of stator teeth circumferentially spaced about the circumference of each stator. The rotor and the stator may be of any suitable size. In one embodiment, the inner diameter of the rotor is about 64 mm and the outer diameter of the stator is about 60 mm. In further embodiments, the rotor and stator may have alternate diameters in order to alter the tip speed and shear pressures. In certain embodiments, each of three stages is operated with a super-fine generator, comprising a gap of between about 0.025 mm and about 3 mm. When a feed stream 205 including solid particles is to be sent through high shear device 200 , the appropriate gap width is first selected for an appropriate reduction in particle size and increase in particle surface area. In embodiments, this is beneficial for increasing catalyst surface area by shearing and dispersing the particles. High shear device 200 is fed a reaction mixture comprising the feed stream 205 . Feed stream 205 comprises an emulsion of the dispersible phase and the continuous phase. Emulsion refers to a liquefied mixture that contains two distinguishable substances (or phases) that will not readily mix and dissolve together. Most emulsions have a continuous phase (or matrix), which holds therein discontinuous droplets, bubbles, and/or particles of the other phase or substance. Emulsions may be highly viscous, such as slurries or pastes, or may be foams, with tiny gas bubbles suspended in a liquid. As used herein, the term “emulsion” encompasses continuous phases comprising gas bubbles, continuous phases comprising particles (e.g., solid catalyst), continuous phases comprising droplets of a fluid that is substantially insoluble in the continuous phase, and combinations thereof. Feed stream 205 may include a particulate solid catalyst component. Feed stream 205 is pumped through the generators 220 , 230 , 240 , such that product dispersion 210 is formed. In each generator, the rotors 222 , 223 , 224 rotate at high speed relative to the fixed stators 227 , 228 , 229 . The rotation of the rotors pumps fluid, such as the feed stream 205 , between the outer surface of the rotor 222 and the inner surface of the stator 227 creating a localized high shear condition. The gaps 225 , 235 , 245 generate high shear forces that process the feed stream 205 . The high shear forces between the rotor and stator functions to process the feed stream 205 to create the product dispersion 210 . Each generator 220 , 230 , 240 of the high shear device 200 has interchangeable rotor-stator combinations for producing a narrow distribution of the desired bubble size, if feedstream 205 comprises a gas, or globule size, if feedstream 205 comprises a liquid, in the product dispersion 210 . The product dispersion 210 of gas particles, or bubbles, in a liquid comprises an emulsion. In embodiments, the product dispersion 210 may comprise a dispersion of a previously immiscible or insoluble gas, liquid or solid into the continuous phase. The product dispersion 210 has an average gas particle, or bubble, size less than about 1.5 μm; preferably the bubbles are sub-micron in diameter. In certain instances, the average bubble size is in the range from about 1.0 μm to about 0.1 μm. Alternatively, the average bubble size is less than about 400 nm (0.4 μm) and most preferably less than about 100 nm (0.1 μm). The high shear device 200 produces a gas emulsion capable of remaining dispersed at atmospheric pressure for at least about 15 minutes. For the purpose of this disclosure, an emulsion of gas particles, or bubbles, in the dispersed phase in product dispersion 210 that are less than 1.5 μm in diameter may comprise a micro-foam. Not to be limited by a specific theory, it is known in emulsion chemistry that sub-micron particles, or bubbles, dispersed in a liquid undergo movement primarily through Brownian motion effects. The bubbles in the emulsion of product dispersion 210 created by the high shear device 200 may have greater mobility through boundary layers of solid catalyst particles, thereby facilitating and accelerating the catalytic reaction through enhanced transport of reactants. The rotor is set to rotate at a speed commensurate with the diameter of the rotor and the desired tip speed as described hereinabove. Transport resistance is reduced by incorporation of high shear device 200 such that the velocity of the reaction is increased by at least about 5%. Alternatively, the high shear device 200 comprises a high shear colloid mill that serves as an accelerated rate reactor (ARR). The accelerated rate reactor comprises a single stage dispersing chamber. The accelerated rate reactor comprises a multiple stage inline disperser comprising at least 2 stages. Selection of the high shear device 200 is dependent on throughput requirements and desired particle or bubble size in the outlet dispersion 210 . In certain instances, high shear device 200 comprises a Dispax Reactor® of IKA® Works, Inc. Wilmington, N.C. and APV North America, Inc. Wilmington, Mass. Model DR 2000/4, for example, comprises a belt drive, 4M generator, PTFE sealing ring, inlet flange 1″ sanitary clamp, outlet flange ¾″ sanitary clamp, 2 HP power, output speed of 7900 rpm, flow capacity (water) approximately 300 l/h to approximately 700 l/h (depending on generator), a tip speed of from 9.4 m/s to about 41 m/s (about 1850 ft/min to about 8070 ft/min). Several alternative models are available having various inlet/outlet connections, horsepower, nominal tip speeds, output rpm, and nominal flow rate. Without wishing to be limited to a particular theory, it is believed that the level or degree of high shear mixing is sufficient to increase rates of mass transfer and may also produce localized non-ideal conditions that enable reactions to occur that would not otherwise be expected to occur based on Gibbs free energy predictions. Localized non ideal conditions are believed to occur within the high shear device resulting in increased temperatures and pressures with the most significant increase believed to be in localized pressures. The increase in pressures and temperatures within the high shear device are instantaneous and localized and quickly revert back to bulk or average system conditions once exiting the high shear device. In some cases, the high shear device induces cavitation of sufficient intensity to dissociate one or more of the reactants into free radicals, which may intensify a chemical reaction or allow a reaction to take place at less stringent conditions than might otherwise be required. Cavitation may also increase rates of transport processes by producing local turbulence and liquid micro-circulation (acoustic streaming). Vessel. Vessel or reactor 110 is any type of vessel in which a multiphase reaction can be propagated to carry out the above-described conversion reaction(s). For instance, a continuous or semi-continuous stirred tank reactor, or one or more batch reactors may be employed in series or in parallel. In some applications vessel 110 may be a tower reactor, and in others a tubular reactor or multi-tubular reactor. A catalyst inlet line 115 may be connected to vessel 110 for receiving a catalyst solution or slurry during operation of the system. Vessel 110 may include one or more of the following components: stirring system, heating and/or cooling capabilities, pressure measurement instrumentation, temperature measurement instrumentation, one or more injection points, and level regulator (not shown), as are known in the art of reaction vessel design. For example, a stirring system may include a motor driven mixer. A heating and/or cooling apparatus may comprise, for example, a heat exchanger. Alternatively, as much of the conversion reaction may occur within HSD 140 in some embodiments, vessel 110 may serve primarily as a storage vessel in some cases. Heat Transfer Devices. In addition to the above-mentioned heating/cooling capabilities of vessel 110 , other external or internal heat transfer devices for heating or cooling a process stream are also contemplated in variations of the embodiments illustrated in FIG. 1 . Some suitable locations for one or more such heat transfer devices are between pump 105 and HSD 140 , between HSD 140 and vessel 110 , and between vessel 110 and pump 105 when system 100 is operated in multi-pass mode. Some non-limiting examples of such heat transfer devices are shell, tube, plate, and coil heat exchangers, as are known in the art. Pumps. Pump 105 is configured for either continuous or semi-continuous operation, and may be any suitable pumping device that is capable of providing greater than 2 atm pressure, preferably greater than 3 atm pressure, to allow controlled flow through HSD 140 and system 100 . For example, a Roper Type 1 gear pump, Roper Pump Company (Commerce Ga.) Dayton Pressure Booster Pump Model 2P372E, Dayton Electric Co (Niles, Ill.) is one suitable pump. Preferably, all contact parts of pump 105 are stainless steel, for example, 316 stainless steel. In embodiments, for example, wherein corrosive substances will be pumped (e.g. sulfuric acid) it may be desirable to have gold plated contact surfaces. In some embodiments of the system, pump 105 is capable of pressures greater than about 20 atm. In addition to pump 105 , one or more additional, high pressure pump (not shown) may be included in the system illustrated in FIG. 1 . For example, a booster pump, which may be similar to pump 105 , may be included between HSD 140 and vessel 110 for boosting the pressure into vessel 110 . Production of Chorohydrins. In operation for the chlorination of olefins, respectively, a dispersible olefin gas stream is introduced into system 100 via line 122 , and combined in line 113 with a liquid stream to form a gas-liquid stream. The liquid stream includes a chlorinating agent in aqueous phase (i.e. Cl 2 dissolved in water). Alternatively, the olefin gas may be fed directly into HSD 140 , instead of being combined with the liquid reactant (i.e., water) in line 113 . Pump 105 is operated to pump the liquid reactant (water) through line 121 , and to build pressure and feed HSD 140 , providing a controlled flow throughout high shear (HSD) 140 and high shear system 100 . Optionally, a gaseous chlorinating agent such as chlorine gas may be fed into line 121 through line 111 . In such an embodiment, an additional high shear device may be incorporated to dissolve the gaseous chlorinating agent into solution. In a preferred embodiment, olefin gas 122 may continuously be fed into the liquid stream 112 to form high shear feed stream 113 (e.g. gas-liquid stream). In high shear device 140 , liquid (i.e. water), chlorinating agent, and the olefin vapor are highly dispersed such that nanobubbles and/or microbubbles of olefin are formed for superior dissolution of olefin vapor into solution. Once dispersed, the dispersion may exit high shear device 140 at high shear outlet line 118 . Stream 118 may optionally enter fluidized or fixed bed 142 in lieu of a slurry catalyst process. However, in a slurry catalyst embodiment, high shear outlet stream 118 may directly enter hydration reactor 110 for hydration. The reaction stream may be maintained at the specified reaction temperature, using cooling coils in the reactor 110 to maintain reaction temperature. Chlorination products (e.g. chlorohydrins) may be withdrawn at product stream 116 . In an exemplary embodiment, the high shear device comprises a commercial disperser such as IKA® model DR 2000/4, a high shear, three stage dispersing device configured with three rotors in combination with stators, aligned in series. The disperser is used to create the dispersion of olefins in the liquid medium comprising water (i.e., “the reactants”). The rotor/stator sets may be configured as illustrated in FIG. 2 , for example. The combined reactants enter the high shear device via line 113 and enter a first stage rotor/stator combination having circumferentially spaced first stage shear openings. The coarse dispersion exiting the first stage enters the second rotor/stator stage, which has second stage shear openings. The reduced bubble-size dispersion emerging from the second stage enters the third stage rotor/stator combination having third stage shear openings. The dispersion exits the high shear device via line 118 . In some embodiments, the shear rate increases stepwise longitudinally along the direction of the flow. For example, in some embodiments, the shear rate in the first rotor/stator stage is greater than the shear rate in subsequent stage(s). In other embodiments, the shear rate is substantially constant along the direction of the flow, with the stage or stages being the same. If the high shear device includes a PTFE seal, for example, the seal may be cooled using any suitable technique that is known in the art. For example, the reactant stream flowing in line 113 may be used to cool the seal and in so doing be preheated as desired prior to entering the high shear device. The rotor of HSD 140 is set to rotate at a speed commensurate with the diameter of the rotor and the desired tip speed. As described above, the high shear device (e.g., colloid mill) has either a fixed clearance between the stator and rotor or has adjustable clearance. HSD 140 serves to intimately mix the olefin vapor and the reactant liquid (i.e., water). In some embodiments of the process, the transport resistance of the reactants is reduced by operation of the high shear device such that the velocity of the reaction (i.e. reaction rate) is increased by greater than a factor of about 5. In some embodiments, the velocity of the reaction is increased by at least a factor of 10. In some embodiments, the velocity is increased by a factor in the range of about 10 to about 100 fold. In some embodiments, HSD 140 delivers at least 300 L/h with a power consumption of 1.5 kW at a nominal tip speed of at least 4500 ft/min, and which may exceed 7900 ft/min (140 m/sec). Although measurement of instantaneous temperature and pressure at the tip of a rotating shear unit or revolving element in HSD 140 is difficult, it is estimated that the localized temperature seen by the intimately mixed reactants may be in excess of 500° C. and at pressures in excess of 500 kg/cm 2 under high shear conditions. The high shear results in dispersion of the olefin gas in micron or submicron-sized bubbles. In some embodiments, the resultant dispersion has an average bubble size less than about 1.5 μm. Accordingly, the dispersion exiting HSD 140 via line 118 comprises micron and/or submicron-sized gas bubbles. In some embodiments, the mean bubble size is in the range of about 0.4 μm to about 1.5 μm. In some embodiments, the mean bubble size is less than about 400 nm, and may be about 100 nm in some cases. In many embodiments, the microbubble dispersion is able to remain dispersed at atmospheric pressure for at least 15 minutes. Once dispersed, the resulting olefin/chlorinating agent/water dispersion exits HSD 140 via line 118 and feeds into vessel 110 , as illustrated in FIG. 1 . As a result of the intimate mixing of the reactants prior to entering vessel 110 , a significant portion of the chemical reaction may take place in HSD 140 , with or without the presence of a catalyst. Accordingly, in some embodiments, reactor/vessel 110 may be used primarily for heating and separation of volatile reaction products from the chlorohydrin product. Alternatively, or additionally, vessel 110 may serve as a primary reaction vessel where most of the chlorohydrin product is produced. Vessel/reactor 110 may be operated in either continuous or semi-continuous flow mode, or it may be operated in batch mode. The contents of vessel 110 may be maintained at a specified reaction temperature using heating and/or cooling capabilities (e.g., cooling coils) and temperature measurement instrumentation. Pressure in the vessel may be monitored using suitable pressure measurement instrumentation, and the level of reactants in the vessel may be controlled using a level regulator (not shown), employing techniques that are known to those of skill in the art. The contents are stirred continuously or semi-continuously. Embodiments of the process generally comprise contacting a chlorine source with an olefin under conditions sufficient to form a chlorohydrin. The chlorine source or chlorinating agent may be any source of chlorine that is capable of forming a chlorinating species. Examples of such chlorine sources are chlorine (Cl 2 ), hypochlorous acid (HOCl), chlorine monoxide (Cl 2 O), or a hypochlorite (—OCl) of an alkali metal or alkaline earth metal. The chlorine source is preferably Cl 2 , more preferably, Cl 2 gas. The chlorinating species may also comprise at least one compound selected from the group consisting of hypochlorous acid, alkali metal hypohalites, and alkaline earth metal hypohalites. Preferably, chlorine source or chlorinating agent is in an aqueous or liquid phase. In on embodiment, the chlorine source or agent may be dissolved in water. In an embodiment, the method may comprise contacting the chlorinating species with at least one unsaturated organic compound containing from 2 to 10 carbon atoms, preferably 2 to 8 carbons, and more preferably 2 to 6 carbons. The unsaturated organic compound may be selected from the group consisting of substituted and unsubstituted olefins and cyclic olefins. The substituted olefins may have substituents selected from the group consisting of an alkyl radical, a phenyl radical and an alkylphenyl radical (i.e. tolyl, xylyl or ethylphenyl). Each of these radicals may also be unsubstituted or substituted. When substituted, the substituents preferably comprise halides, hydroxides, or inert substituents. By “inert substituents” it is meant that the substituents do not interfere with the process of this invention. Any suitable unsaturated compound containing from 2 to 10 carbon atoms and meeting the criteria specified above can be used in the process of the invention to prepare the corresponding chlorohydrin. Such unsaturated organic compounds include, but are not limited to, ethylene, propylene, butylene, hexene, cyclohexene, cyclopentene, cyclooctene, and mixtures thereof. Examples of substituted olefins include allyl alcohol, allyl chloride, styrene, 4-bromo-1-butene, 3-chloro-1-butene, 3-chloro-2-methylpropene, 1-hexene-3-ol, 3-butene-2-ol, 3-pentene-2-ol, 1-octene-3-ol, and mixtures thereof. The reaction may proceed under temperature and pressure conditions commonly employed in such catalytic chlorination reactions. Generally, embodiments of the process are carried out by reacting a olefin containing about 1 to about 10 carbon atoms with a chlorine source to obtain the desired chlorohydrin reaction product. More specifically, the chlorination reaction in reactor 110 may be conducted with mixing and at a temperature between 0° C. to 100° C. and pressure between ambient to 100 psig (791 kPa). Preferably, the temperature is from 20° C. to 80° C., more preferably from 40° C. to 60° C. Multiple Pass Operation. In the embodiment shown in FIG. 1 , the system is configured for single pass operation, wherein the output from vessel 110 goes directly to further processing for recovery of chlorohydrin product. In some embodiments it may be desirable to pass the contents of vessel 110 , or a liquid fraction containing unreacted olefin, through HSD 140 during a second pass. In this case, line 116 is connected to line 121 via dotted line 120 , and the recycle stream from vessel 110 is pumped by pump 105 into line 113 and thence into HSD 140 . Additional olefin gas may be injected via line 122 into line 113 , or it may be added directly into the high shear device (not shown). Multiple High shear Devices. In some embodiments, two or more high shear devices like HSD 140 , or configured differently, are aligned in series, and are used to further enhance the reaction. Their operation may be in either batch or continuous mode. In some instances in which a single pass or “once through” process is desired, the use of multiple high shear devices in series may also be advantageous. In some embodiments where multiple high shear devices are operated in series, vessel 110 may be omitted. In some embodiments, multiple high shear devices 140 are operated in parallel, and the outlet dispersions therefrom are introduced into one or more vessel 110 . While the preferred embodiments of the invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit and teachings of the invention. The embodiments described and the examples provided herein are exemplary only, and are not intended to be limiting. Many variations and modifications of the invention disclosed herein are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited by the description set out above, but is only limited by the claims which follow, that scope including all equivalents of the subject matter of the claims. The discussion of a reference is not an admission that it is prior art to the present invention, especially any reference that may have a publication date after the priority date of this application. The disclosures of all patents, patent applications, and publications cited herein are hereby incorporated herein by reference in their entirety, to the extent that they provide exemplary, procedural, or other details supplementary to those set forth herein.
Methods and systems for the preparation of chlorohydrins are described herein. The methods and systems incorporate the novel use of a high shear device to promote dispersion and solubility of olefins into the chlorinating phase. The high shear device may allow for lower reaction temperatures and pressures and may also reduce chlorination time.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a divisional application of U.S. patent application Ser.", "No. 12/143,492, filed Jun. 20, 2008, which claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 60/946,487, filed Jun. 27, 2007.", "The disclosure of said applications are hereby incorporated herein by reference.", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable.", "BACKGROUND 1.", "Field of the Invention This invention relates generally to the field of chemical reactions.", "More specifically, the invention relates to methods of making chlorohydrins incorporating high shear mixing.", "Background of the Invention Chlorohydrins are useful as intermediates in producing various compounds.", "For example, propylene chlorohydrin and butylene chlorohydrin are used in producing propylene oxide and butylene oxide, respectively.", "Various processes are known for the production of chlorohydrins.", "For example, olefin chlorohydrins are typically prepared by reacting an olefin with chlorine in the presence of water.", "This process is believed to occur by means of an intermediate cyclic chloronium ion which reacts with the water to form an olefin chlorohydrin.", "The olefin may be one containing from 8 to about 30 carbon atoms.", "However, the process also concurrently forms undesirable dichloride byproducts when aqueous chloride ions react with the cyclic chloronium ions.", "Significant yield losses are typically suffered and the byproducts must be separated from the desired olefin chlorohydrin, an operation that adds to the cost of making the chlorohydrin.", "Alternatively, the process described above may include a water immiscible solvent.", "Therefore, the reaction would entail the addition of hypochlorous acid to a long chain olefin in the presence of water in a water immiscible solvent.", "Suitable solvents include decane, chloroform and petroleum ether.", "Other processes for producing chlorohydrins involve reacting olefins with hypochlorous acid, wherein the process requires preliminarily acidifying the olefin with gaseous hydrochloric acid and carrying out the process at a pH of between 2 to 7, and preferably between 5 to 6.", "Another method of making chlorohydrins involves preparing hypochlorous acid by reacting chlorine and water in the presence of alkaline earth metal hydroxides (maintaining a pH below 7.0), then, reacting the hypochlorous acid mixture with a vinyl group-containing compound.", "Alternatively the preparation of chlorohydrin may be achieved by reaction of olephins with trichloroisocyanuric acid in alcohols, acetic acid or aqueous acetone.", "Various other methods of forming chlorohydrins are also well known such as reacting olefins with t-butyl hypochlorite or hypochlorous acid substantially free of chloride ions.", "However, these methods typically either result in the production of numerous byproducts or require various, costly processing steps or long reaction times, thus hindering the commercial viability of the methods.", "For these reasons, there remains a need for a process for producing chlorohydrin that is effective and results in high yields of the desired product.", "In light of the above, it is apparent that research has been focused on different reaction pathways in producing chlorohydrins.", "However, none of these methods discuss improving the solubility and mass transfer of the reactants through improved mixing.", "Consequently, there is a need for accelerated methods for making chlorohydrins by improving the mixing of olefins into the liquid chlorinating phase.", "BRIEF SUMMARY Methods and systems for the preparation of chlorohydrins are described herein.", "The methods and systems incorporate the novel use of a high shear device to promote dispersion and solubility of olefins into the chlorinating phase.", "The high shear device may allow for lower reaction temperatures and pressures and may also reduce chlorination time.", "Further advantages and aspects of the disclosed methods and system are described below.", "In an embodiment, a method of making a chlorohydrin comprises contacting an olefin with a chlorinating agent.", "In an embodiment the liquid is an aqueous solution, a hypochlorous acid solution, an aqueous hypochlorite solution or chlorine dissolved in H 2 O and the gas comprised of an olefin which is reactive under the conditions of mixing with one or more components of the liquid to form reaction products including the desired olefin chlorohydrin product.", "The method also comprises flowing the olefin and the chorinating agent through a high shear device so as to form dispersion with bubbles less than about 1 μm and form a chlorohydrin.", "In an embodiment, a system for making a chlorohydrin comprises at least one high shear device configured for chlorinating an olefin.", "The high shear device comprises a rotor and a stator.", "The rotor and the stator are separated by a shear gap in the range of from about 0.02 mm to about 5 mm.", "The shear gap is a minimum distance between the rotor and the stator.", "The high shear device is capable of producing a tip speed of the at least one rotor of greater than about 23 m/s (4,500 ft/min).", "In addition, the system comprises a pump configured for delivering a liquid stream comprising liquid phase to the high shear device.", "The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood.", "Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention.", "It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention.", "It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.", "BRIEF DESCRIPTION OF THE DRAWINGS For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which: FIG. 1 illustrates a general flow diagram of an embodiment of a process of making chlorohydrins using a high shear device.", "FIG. 2 illustrates a longitudinal cross-section view of a multi-stage high shear device, as employed in an embodiment of the system of FIG. 1 .", "NOTATION AND NOMENCLATURE Certain terms are used throughout the following description and claims to refer to particular system components.", "This document does not intend to distinguish between components that differ in name but not function.", "In the following discussion and in the claims, the terms “including”", "and “comprising”", "are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .”", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The disclosed methods and systems for the chlorination of an olefin employ a high shear mechanical device to provide rapid contact and mixing of the olefin gas and chlorinating agent in a controlled environment in the reactor/mixer device.", "The term “olefin gas”", "as used herein includes both substantially olefin gas as well as gaseous mixtures containing olefin.", "In particular, embodiments of the systems and methods may be used in the production of chlorohydrins from the chlorination of olefins in water.", "Preferably, the method comprises a heterogeneous phase reaction of a chlorine species in liquid phase with an olefin gas.", "The high shear device reduces the mass transfer limitations on the reaction and thus increases the overall reaction rate.", "Chemical reactions involving liquids, gases and solids rely on the laws of kinetics that involve time, temperature, and pressure to define the rate of reactions.", "In cases where it is desirable to react two (or more) raw materials of different phases (e.g. solid and liquid;", "liquid and gas;", "solid, liquid and gas), one of the limiting factors in controlling the rate of reaction involves the contact time of the reactants.", "As used herein, “multi-phase”", "refers to a reaction involving reactions with two or more different phases.", "In the case of heterogeneously catalyzed reactions there is the additional rate limiting factor of having the reacted products removed from the surface of the catalyst to enable the catalyst to catalyze further reactants.", "The chlorination of olefins to produce chlorohydrin is a multiphase reaction.", "During the multiphase reaction, the phases separate spontaneously.", "The presently disclosed method and system whereby the two phases are intimately mixed to form an emulsion enhances contact surface between the reaction components, thus enhancing the reaction.", "The pH of the reaction may have a direct impact on the reaction rate and thus the olefin conversion.", "The pH employed may vary depending on the chlorines present in the aqueous phase.", "The maximum pH is about 8.", "When the aqueous phase contains free chloride ions and molecular chlorine, the pH should not be below 4.5.", "When an essentially chloride and chlorine-free aqueous solution is employed herein, the pH can range as low as 1.", "The process described here in comprises an aqueous phase having a pH ranging from about 2 to about 8.", "Chlorohydrin yield is particularly good in low olefin conversion when an aqueous phase of pH of about 6 is employed.", "In conventional reactors, contact time for the reactants and/or catalyst is often controlled by mixing which provides contact with two or more reactants involved in a chemical reaction.", "Embodiments of the disclosed method comprise an external high shear device to decrease mass transfer limitations and thereby more closely approach kinetic limitations.", "When reaction rates are accelerated, residence times may be decreased, thereby increasing obtainable throughput.", "Alternatively, where the current yield is acceptable, decreasing the required residence time allows for the use of lower temperatures and/or pressures than conventional processes.", "Furthermore, in homogeneous reactions, the disclosed process could be used to provide for uniform temperature distribution within the reactor thereby minimizing potential side reactions.", "System for Production of Chlorohydrin.", "A high shear chlorohydrin production system will now be described in relation to FIG. 1 , which is a process flow diagram of an embodiment of a high shear system (HSS) 100 for the production of chlorohydrin via reacting a chlorinating agent with olefins in a gas-liquid phase reaction.", "The basic components of a representative system include external high shear device (HSD) 140 , vessel 110 , pump 105 and fluidized or fixed bed 142 .", "As shown in FIG. 1 , the high shear device is located external to vessel/reactor 110 .", "Each of these components is further described in more detail below.", "Line 121 is connected to pump 105 for introducing reactant.", "Line 113 connects pump 105 to HSD 140 , line 118 connects HSD 140 to fluidized or fixed bed 142 and line 119 connects bed to vessel 110 .", "Line 122 is connected to line 113 for introducing an oxygen-containing gas (e.g., O 2 or air).", "Line 117 is connected to vessel 110 for removal of unreacted vapor, and other reaction gases.", "High shear devices (HSDs) such as a high shear device, or high shear mill, are generally divided into classes based upon their ability to mix fluids.", "Mixing is the process of reducing the size of inhomogeneous species or particles within the fluid.", "One metric for the degree or thoroughness of mixing is the energy density per unit volume that the mixing device generates to disrupt the fluid particles.", "The classes are distinguished based on delivered energy density.", "There are three classes of industrial mixers having sufficient energy density to consistently produce mixtures or emulsions with particle or bubble sizes in the range of 0 to 50 microns.", "High shear mechanical devices include homogenizers as well as colloid mills.", "Homogenization valve systems are typically classified as high energy devices.", "Fluid to be processed is pumped under very high pressure through a narrow-gap valve into a lower pressure environment.", "The pressure gradients across the valve and the resulting turbulence and cavitations act to break-up any particles in the fluid.", "These valve systems are most commonly used in milk homogenization and can yield average particle size range from about 0.01 μm to about 1 μm.", "At the other end of the spectrum are high shear mixer systems classified as low energy devices.", "These systems usually have paddles or fluid rotors that turn at high speed in a reservoir of fluid to be processed, which in many of the more common applications is a food product.", "These systems are usually used when average particle, or bubble, sizes of greater than 20 microns are acceptable in the processed fluid.", "Between low energy-high shear mixers and homogenization valve systems, in terms of the mixing energy density delivered to the fluid, are colloid mills, which are classified as intermediate energy devices.", "The typical colloid mill configuration includes a conical or disk rotor that is separated from a complementary, liquid-cooled stator by a closely-controlled rotor-stator gap, which is maybe between 0.025 mm and 10.0 mm.", "Rotors are usually driven by an electric motor through a direct drive or belt mechanism.", "Many colloid mills, with proper adjustment, can achieve average particle, or bubble, sizes of about 0.01 μm to about 25 μm in the processed fluid.", "These capabilities render colloid mills appropriate for a variety of applications including colloid and oil/water-based emulsion processing such as that required for cosmetics, mayonnaise, silicone/silver amalgam formation, or roofing-tar mixing.", "An approximation of energy input into the fluid (kW/L/min) can be made by measuring the motor energy (kW) and fluid output (L/min).", "In embodiments, the energy expenditure of a high shear device is greater than 1000 W/m 3 .", "In embodiments, the energy expenditure is in the range of from about 3000 W/m 3 to about 7500 W/m 3 .", "The shear rate generated in a high shear device may be greater than 20,000 s −1 .", "In embodiments, the shear rate generated is in the range of from 20,000 s −1 to 100,000 s −1 .", "Tip speed is the velocity (m/sec) associated with the end of one or more revolving elements that is transmitting energy to the reactants.", "Tip speed, for a rotating element, is the circumferential distance traveled by the tip of the rotor per unit of time, and is generally defined by the equation V (m/sec)=π·D·n, where V is the tip speed, D is the diameter of the rotor, in meters, and n is the rotational speed of the rotor, in revolutions per second.", "Tip speed is thus a function of the rotor diameter and the rotation rate.", "Also, tip speed may be calculated by multiplying the circumferential distance transcribed by the rotor tip, 2πR, where R is the radius of the rotor (meters, for example) times the frequency of revolution (for example revolutions (meters, for example) times the frequency of revolution (for example revolutions per minute, rpm).", "For colloid mills, typical tip speeds are in excess of 23 m/sec (4500 ft/min) and can exceed 40 m/sec (7900 ft/min).", "For the purpose of the present disclosure the term ‘high shear’ refers to mechanical rotor-stator devices, such as mills or mixers, that are capable of tip speeds in excess of 5 m/sec (1000 ft/min) and require an external mechanically driven power device to drive energy into the stream of products to be reacted.", "A high shear device combines high tip speeds with a very small shear gap to produce significant friction on the material being processed.", "Accordingly, a local pressure in the range of about 1000 MPa (about 145,000 psi) to about 1050 MPa (152,300 psi) and elevated temperatures at the tip of the shear mixer are produced during operation.", "In certain embodiments, the local pressure is at least about 1034 MPa (about 150,000 psi).", "Referring now to FIG. 2 , there is presented a schematic diagram of a high shear device 200 .", "High shear device 200 comprises at least one rotor-stator combination.", "The rotor-stator combinations may also be known as generators 220 , 230 , 240 or stages without limitation.", "The high shear device 200 comprises at least two generators, and most preferably, the high shear device comprises at least three generators.", "The first generator 220 comprises rotor 222 and stator 227 .", "The second generator 230 comprises rotor 223 , and stator 228 ;", "the third generator comprises rotor 224 and stator 229 .", "For each generator 220 , 230 , 240 the rotor is rotatably driven by input 250 .", "The generators 220 , 230 , 240 rotate about axis 260 in rotational direction 265 .", "Stator 227 is fixably coupled to the high shear device wall 255 .", "The generators include gaps between the rotor and the stator.", "The first generator 220 comprises a first gap 225 ;", "the second generator 230 comprises a second gap 235 ;", "and the third generator 240 comprises a third gap 245 .", "The gaps 225 , 235 , 245 are between about 0.025 mm (0.01 in) and 10.0 mm (0.4 in) wide.", "Alternatively, the process comprises utilization of a high shear device 200 wherein the gaps 225 , 235 , 245 are between about 0.5 mm (0.02 in) and about 2.5 mm (0.1 in).", "In certain instances the gap is maintained at about 1.5 mm (0.06 in).", "Alternatively, the gaps 225 , 235 , 245 are different between generators 220 , 230 , 240 .", "In certain instances, the gap 225 for the first generator 220 is greater than about the gap 235 for the second generator 230 , which is greater than about the gap 245 for the third generator 240 .", "Additionally, the width of the gaps 225 , 235 , 245 may comprise a coarse, medium, fine, and super-fine characterization.", "Rotors 222 , 223 , and 224 and stators 227 , 228 , and 229 may be toothed designs.", "Each generator may comprise two or more sets of rotor-stator teeth, as known in the art.", "Rotors 222 , 223 , and 224 may comprise a number of rotor teeth circumferentially spaced about the circumference of each rotor.", "Stators 227 , 228 , and 229 may comprise a number of stator teeth circumferentially spaced about the circumference of each stator.", "The rotor and the stator may be of any suitable size.", "In one embodiment, the inner diameter of the rotor is about 64 mm and the outer diameter of the stator is about 60 mm.", "In further embodiments, the rotor and stator may have alternate diameters in order to alter the tip speed and shear pressures.", "In certain embodiments, each of three stages is operated with a super-fine generator, comprising a gap of between about 0.025 mm and about 3 mm.", "When a feed stream 205 including solid particles is to be sent through high shear device 200 , the appropriate gap width is first selected for an appropriate reduction in particle size and increase in particle surface area.", "In embodiments, this is beneficial for increasing catalyst surface area by shearing and dispersing the particles.", "High shear device 200 is fed a reaction mixture comprising the feed stream 205 .", "Feed stream 205 comprises an emulsion of the dispersible phase and the continuous phase.", "Emulsion refers to a liquefied mixture that contains two distinguishable substances (or phases) that will not readily mix and dissolve together.", "Most emulsions have a continuous phase (or matrix), which holds therein discontinuous droplets, bubbles, and/or particles of the other phase or substance.", "Emulsions may be highly viscous, such as slurries or pastes, or may be foams, with tiny gas bubbles suspended in a liquid.", "As used herein, the term “emulsion”", "encompasses continuous phases comprising gas bubbles, continuous phases comprising particles (e.g., solid catalyst), continuous phases comprising droplets of a fluid that is substantially insoluble in the continuous phase, and combinations thereof.", "Feed stream 205 may include a particulate solid catalyst component.", "Feed stream 205 is pumped through the generators 220 , 230 , 240 , such that product dispersion 210 is formed.", "In each generator, the rotors 222 , 223 , 224 rotate at high speed relative to the fixed stators 227 , 228 , 229 .", "The rotation of the rotors pumps fluid, such as the feed stream 205 , between the outer surface of the rotor 222 and the inner surface of the stator 227 creating a localized high shear condition.", "The gaps 225 , 235 , 245 generate high shear forces that process the feed stream 205 .", "The high shear forces between the rotor and stator functions to process the feed stream 205 to create the product dispersion 210 .", "Each generator 220 , 230 , 240 of the high shear device 200 has interchangeable rotor-stator combinations for producing a narrow distribution of the desired bubble size, if feedstream 205 comprises a gas, or globule size, if feedstream 205 comprises a liquid, in the product dispersion 210 .", "The product dispersion 210 of gas particles, or bubbles, in a liquid comprises an emulsion.", "In embodiments, the product dispersion 210 may comprise a dispersion of a previously immiscible or insoluble gas, liquid or solid into the continuous phase.", "The product dispersion 210 has an average gas particle, or bubble, size less than about 1.5 μm;", "preferably the bubbles are sub-micron in diameter.", "In certain instances, the average bubble size is in the range from about 1.0 μm to about 0.1 μm.", "Alternatively, the average bubble size is less than about 400 nm (0.4 μm) and most preferably less than about 100 nm (0.1 μm).", "The high shear device 200 produces a gas emulsion capable of remaining dispersed at atmospheric pressure for at least about 15 minutes.", "For the purpose of this disclosure, an emulsion of gas particles, or bubbles, in the dispersed phase in product dispersion 210 that are less than 1.5 μm in diameter may comprise a micro-foam.", "Not to be limited by a specific theory, it is known in emulsion chemistry that sub-micron particles, or bubbles, dispersed in a liquid undergo movement primarily through Brownian motion effects.", "The bubbles in the emulsion of product dispersion 210 created by the high shear device 200 may have greater mobility through boundary layers of solid catalyst particles, thereby facilitating and accelerating the catalytic reaction through enhanced transport of reactants.", "The rotor is set to rotate at a speed commensurate with the diameter of the rotor and the desired tip speed as described hereinabove.", "Transport resistance is reduced by incorporation of high shear device 200 such that the velocity of the reaction is increased by at least about 5%.", "Alternatively, the high shear device 200 comprises a high shear colloid mill that serves as an accelerated rate reactor (ARR).", "The accelerated rate reactor comprises a single stage dispersing chamber.", "The accelerated rate reactor comprises a multiple stage inline disperser comprising at least 2 stages.", "Selection of the high shear device 200 is dependent on throughput requirements and desired particle or bubble size in the outlet dispersion 210 .", "In certain instances, high shear device 200 comprises a Dispax Reactor® of IKA® Works, Inc. Wilmington, N.C. and APV North America, Inc. Wilmington, Mass.", "Model DR 2000/4, for example, comprises a belt drive, 4M generator, PTFE sealing ring, inlet flange 1″ sanitary clamp, outlet flange ¾″ sanitary clamp, 2 HP power, output speed of 7900 rpm, flow capacity (water) approximately 300 l/h to approximately 700 l/h (depending on generator), a tip speed of from 9.4 m/s to about 41 m/s (about 1850 ft/min to about 8070 ft/min).", "Several alternative models are available having various inlet/outlet connections, horsepower, nominal tip speeds, output rpm, and nominal flow rate.", "Without wishing to be limited to a particular theory, it is believed that the level or degree of high shear mixing is sufficient to increase rates of mass transfer and may also produce localized non-ideal conditions that enable reactions to occur that would not otherwise be expected to occur based on Gibbs free energy predictions.", "Localized non ideal conditions are believed to occur within the high shear device resulting in increased temperatures and pressures with the most significant increase believed to be in localized pressures.", "The increase in pressures and temperatures within the high shear device are instantaneous and localized and quickly revert back to bulk or average system conditions once exiting the high shear device.", "In some cases, the high shear device induces cavitation of sufficient intensity to dissociate one or more of the reactants into free radicals, which may intensify a chemical reaction or allow a reaction to take place at less stringent conditions than might otherwise be required.", "Cavitation may also increase rates of transport processes by producing local turbulence and liquid micro-circulation (acoustic streaming).", "Vessel.", "Vessel or reactor 110 is any type of vessel in which a multiphase reaction can be propagated to carry out the above-described conversion reaction(s).", "For instance, a continuous or semi-continuous stirred tank reactor, or one or more batch reactors may be employed in series or in parallel.", "In some applications vessel 110 may be a tower reactor, and in others a tubular reactor or multi-tubular reactor.", "A catalyst inlet line 115 may be connected to vessel 110 for receiving a catalyst solution or slurry during operation of the system.", "Vessel 110 may include one or more of the following components: stirring system, heating and/or cooling capabilities, pressure measurement instrumentation, temperature measurement instrumentation, one or more injection points, and level regulator (not shown), as are known in the art of reaction vessel design.", "For example, a stirring system may include a motor driven mixer.", "A heating and/or cooling apparatus may comprise, for example, a heat exchanger.", "Alternatively, as much of the conversion reaction may occur within HSD 140 in some embodiments, vessel 110 may serve primarily as a storage vessel in some cases.", "Heat Transfer Devices.", "In addition to the above-mentioned heating/cooling capabilities of vessel 110 , other external or internal heat transfer devices for heating or cooling a process stream are also contemplated in variations of the embodiments illustrated in FIG. 1 .", "Some suitable locations for one or more such heat transfer devices are between pump 105 and HSD 140 , between HSD 140 and vessel 110 , and between vessel 110 and pump 105 when system 100 is operated in multi-pass mode.", "Some non-limiting examples of such heat transfer devices are shell, tube, plate, and coil heat exchangers, as are known in the art.", "Pumps.", "Pump 105 is configured for either continuous or semi-continuous operation, and may be any suitable pumping device that is capable of providing greater than 2 atm pressure, preferably greater than 3 atm pressure, to allow controlled flow through HSD 140 and system 100 .", "For example, a Roper Type 1 gear pump, Roper Pump Company (Commerce Ga.) Dayton Pressure Booster Pump Model 2P372E, Dayton Electric Co (Niles, Ill.) is one suitable pump.", "Preferably, all contact parts of pump 105 are stainless steel, for example, 316 stainless steel.", "In embodiments, for example, wherein corrosive substances will be pumped (e.g. sulfuric acid) it may be desirable to have gold plated contact surfaces.", "In some embodiments of the system, pump 105 is capable of pressures greater than about 20 atm.", "In addition to pump 105 , one or more additional, high pressure pump (not shown) may be included in the system illustrated in FIG. 1 .", "For example, a booster pump, which may be similar to pump 105 , may be included between HSD 140 and vessel 110 for boosting the pressure into vessel 110 .", "Production of Chorohydrins.", "In operation for the chlorination of olefins, respectively, a dispersible olefin gas stream is introduced into system 100 via line 122 , and combined in line 113 with a liquid stream to form a gas-liquid stream.", "The liquid stream includes a chlorinating agent in aqueous phase (i.e. Cl 2 dissolved in water).", "Alternatively, the olefin gas may be fed directly into HSD 140 , instead of being combined with the liquid reactant (i.e., water) in line 113 .", "Pump 105 is operated to pump the liquid reactant (water) through line 121 , and to build pressure and feed HSD 140 , providing a controlled flow throughout high shear (HSD) 140 and high shear system 100 .", "Optionally, a gaseous chlorinating agent such as chlorine gas may be fed into line 121 through line 111 .", "In such an embodiment, an additional high shear device may be incorporated to dissolve the gaseous chlorinating agent into solution.", "In a preferred embodiment, olefin gas 122 may continuously be fed into the liquid stream 112 to form high shear feed stream 113 (e.g. gas-liquid stream).", "In high shear device 140 , liquid (i.e. water), chlorinating agent, and the olefin vapor are highly dispersed such that nanobubbles and/or microbubbles of olefin are formed for superior dissolution of olefin vapor into solution.", "Once dispersed, the dispersion may exit high shear device 140 at high shear outlet line 118 .", "Stream 118 may optionally enter fluidized or fixed bed 142 in lieu of a slurry catalyst process.", "However, in a slurry catalyst embodiment, high shear outlet stream 118 may directly enter hydration reactor 110 for hydration.", "The reaction stream may be maintained at the specified reaction temperature, using cooling coils in the reactor 110 to maintain reaction temperature.", "Chlorination products (e.g. chlorohydrins) may be withdrawn at product stream 116 .", "In an exemplary embodiment, the high shear device comprises a commercial disperser such as IKA® model DR 2000/4, a high shear, three stage dispersing device configured with three rotors in combination with stators, aligned in series.", "The disperser is used to create the dispersion of olefins in the liquid medium comprising water (i.e., “the reactants”).", "The rotor/stator sets may be configured as illustrated in FIG. 2 , for example.", "The combined reactants enter the high shear device via line 113 and enter a first stage rotor/stator combination having circumferentially spaced first stage shear openings.", "The coarse dispersion exiting the first stage enters the second rotor/stator stage, which has second stage shear openings.", "The reduced bubble-size dispersion emerging from the second stage enters the third stage rotor/stator combination having third stage shear openings.", "The dispersion exits the high shear device via line 118 .", "In some embodiments, the shear rate increases stepwise longitudinally along the direction of the flow.", "For example, in some embodiments, the shear rate in the first rotor/stator stage is greater than the shear rate in subsequent stage(s).", "In other embodiments, the shear rate is substantially constant along the direction of the flow, with the stage or stages being the same.", "If the high shear device includes a PTFE seal, for example, the seal may be cooled using any suitable technique that is known in the art.", "For example, the reactant stream flowing in line 113 may be used to cool the seal and in so doing be preheated as desired prior to entering the high shear device.", "The rotor of HSD 140 is set to rotate at a speed commensurate with the diameter of the rotor and the desired tip speed.", "As described above, the high shear device (e.g., colloid mill) has either a fixed clearance between the stator and rotor or has adjustable clearance.", "HSD 140 serves to intimately mix the olefin vapor and the reactant liquid (i.e., water).", "In some embodiments of the process, the transport resistance of the reactants is reduced by operation of the high shear device such that the velocity of the reaction (i.e. reaction rate) is increased by greater than a factor of about 5.", "In some embodiments, the velocity of the reaction is increased by at least a factor of 10.", "In some embodiments, the velocity is increased by a factor in the range of about 10 to about 100 fold.", "In some embodiments, HSD 140 delivers at least 300 L/h with a power consumption of 1.5 kW at a nominal tip speed of at least 4500 ft/min, and which may exceed 7900 ft/min (140 m/sec).", "Although measurement of instantaneous temperature and pressure at the tip of a rotating shear unit or revolving element in HSD 140 is difficult, it is estimated that the localized temperature seen by the intimately mixed reactants may be in excess of 500° C. and at pressures in excess of 500 kg/cm 2 under high shear conditions.", "The high shear results in dispersion of the olefin gas in micron or submicron-sized bubbles.", "In some embodiments, the resultant dispersion has an average bubble size less than about 1.5 μm.", "Accordingly, the dispersion exiting HSD 140 via line 118 comprises micron and/or submicron-sized gas bubbles.", "In some embodiments, the mean bubble size is in the range of about 0.4 μm to about 1.5 μm.", "In some embodiments, the mean bubble size is less than about 400 nm, and may be about 100 nm in some cases.", "In many embodiments, the microbubble dispersion is able to remain dispersed at atmospheric pressure for at least 15 minutes.", "Once dispersed, the resulting olefin/chlorinating agent/water dispersion exits HSD 140 via line 118 and feeds into vessel 110 , as illustrated in FIG. 1 .", "As a result of the intimate mixing of the reactants prior to entering vessel 110 , a significant portion of the chemical reaction may take place in HSD 140 , with or without the presence of a catalyst.", "Accordingly, in some embodiments, reactor/vessel 110 may be used primarily for heating and separation of volatile reaction products from the chlorohydrin product.", "Alternatively, or additionally, vessel 110 may serve as a primary reaction vessel where most of the chlorohydrin product is produced.", "Vessel/reactor 110 may be operated in either continuous or semi-continuous flow mode, or it may be operated in batch mode.", "The contents of vessel 110 may be maintained at a specified reaction temperature using heating and/or cooling capabilities (e.g., cooling coils) and temperature measurement instrumentation.", "Pressure in the vessel may be monitored using suitable pressure measurement instrumentation, and the level of reactants in the vessel may be controlled using a level regulator (not shown), employing techniques that are known to those of skill in the art.", "The contents are stirred continuously or semi-continuously.", "Embodiments of the process generally comprise contacting a chlorine source with an olefin under conditions sufficient to form a chlorohydrin.", "The chlorine source or chlorinating agent may be any source of chlorine that is capable of forming a chlorinating species.", "Examples of such chlorine sources are chlorine (Cl 2 ), hypochlorous acid (HOCl), chlorine monoxide (Cl 2 O), or a hypochlorite (—OCl) of an alkali metal or alkaline earth metal.", "The chlorine source is preferably Cl 2 , more preferably, Cl 2 gas.", "The chlorinating species may also comprise at least one compound selected from the group consisting of hypochlorous acid, alkali metal hypohalites, and alkaline earth metal hypohalites.", "Preferably, chlorine source or chlorinating agent is in an aqueous or liquid phase.", "In on embodiment, the chlorine source or agent may be dissolved in water.", "In an embodiment, the method may comprise contacting the chlorinating species with at least one unsaturated organic compound containing from 2 to 10 carbon atoms, preferably 2 to 8 carbons, and more preferably 2 to 6 carbons.", "The unsaturated organic compound may be selected from the group consisting of substituted and unsubstituted olefins and cyclic olefins.", "The substituted olefins may have substituents selected from the group consisting of an alkyl radical, a phenyl radical and an alkylphenyl radical (i.e. tolyl, xylyl or ethylphenyl).", "Each of these radicals may also be unsubstituted or substituted.", "When substituted, the substituents preferably comprise halides, hydroxides, or inert substituents.", "By “inert substituents”", "it is meant that the substituents do not interfere with the process of this invention.", "Any suitable unsaturated compound containing from 2 to 10 carbon atoms and meeting the criteria specified above can be used in the process of the invention to prepare the corresponding chlorohydrin.", "Such unsaturated organic compounds include, but are not limited to, ethylene, propylene, butylene, hexene, cyclohexene, cyclopentene, cyclooctene, and mixtures thereof.", "Examples of substituted olefins include allyl alcohol, allyl chloride, styrene, 4-bromo-1-butene, 3-chloro-1-butene, 3-chloro-2-methylpropene, 1-hexene-3-ol, 3-butene-2-ol, 3-pentene-2-ol, 1-octene-3-ol, and mixtures thereof.", "The reaction may proceed under temperature and pressure conditions commonly employed in such catalytic chlorination reactions.", "Generally, embodiments of the process are carried out by reacting a olefin containing about 1 to about 10 carbon atoms with a chlorine source to obtain the desired chlorohydrin reaction product.", "More specifically, the chlorination reaction in reactor 110 may be conducted with mixing and at a temperature between 0° C. to 100° C. and pressure between ambient to 100 psig (791 kPa).", "Preferably, the temperature is from 20° C. to 80° C., more preferably from 40° C. to 60° C. Multiple Pass Operation.", "In the embodiment shown in FIG. 1 , the system is configured for single pass operation, wherein the output from vessel 110 goes directly to further processing for recovery of chlorohydrin product.", "In some embodiments it may be desirable to pass the contents of vessel 110 , or a liquid fraction containing unreacted olefin, through HSD 140 during a second pass.", "In this case, line 116 is connected to line 121 via dotted line 120 , and the recycle stream from vessel 110 is pumped by pump 105 into line 113 and thence into HSD 140 .", "Additional olefin gas may be injected via line 122 into line 113 , or it may be added directly into the high shear device (not shown).", "Multiple High shear Devices.", "In some embodiments, two or more high shear devices like HSD 140 , or configured differently, are aligned in series, and are used to further enhance the reaction.", "Their operation may be in either batch or continuous mode.", "In some instances in which a single pass or “once through”", "process is desired, the use of multiple high shear devices in series may also be advantageous.", "In some embodiments where multiple high shear devices are operated in series, vessel 110 may be omitted.", "In some embodiments, multiple high shear devices 140 are operated in parallel, and the outlet dispersions therefrom are introduced into one or more vessel 110 .", "While the preferred embodiments of the invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit and teachings of the invention.", "The embodiments described and the examples provided herein are exemplary only, and are not intended to be limiting.", "Many variations and modifications of the invention disclosed herein are possible and are within the scope of the invention.", "Accordingly, the scope of protection is not limited by the description set out above, but is only limited by the claims which follow, that scope including all equivalents of the subject matter of the claims.", "The discussion of a reference is not an admission that it is prior art to the present invention, especially any reference that may have a publication date after the priority date of this application.", "The disclosures of all patents, patent applications, and publications cited herein are hereby incorporated herein by reference in their entirety, to the extent that they provide exemplary, procedural, or other details supplementary to those set forth herein." ]
RELATED APPLICATION [0001] This application is a continuation of U.S. patent application Ser. No. 10/438,883 filed May 16, 2003, which is incorporated by reference herein in its entirety. FIELD OF INVENTION [0002] The present invention is generally directed toward an implant and is more specifically directed toward an allograft implant having a cartilage face and bone body which has been treated to remove cellular debris and proteoglycans and is shaped for an interference fit implantation in a shoulder or knee joint. The implant is provided with channels which allow transport of cellular materials throughout the implant site to stimulate cartilage growth BACKGROUND OF THE INVENTION [0003] Articular cartilage injury and degeneration present medical problems to the general population which are constantly addressed by orthopedic surgeons. Every year in the United States, over 500,000 arthroplastic or joint repair procedures are performed. These include approximately 125,000 total hip and 150,000 total knee arthroplastics and over 41,000 open arthroscopic procedures to repair cartilaginous defects of the knee. [0004] In the knee joint, the articular cartilage tissue forms a lining which faces the joint cavity on one side and is linked to the subchondral bone plate by a narrow layer of calcified cartilage tissue on the other. Articular cartilage (hyaline cartilage) consists primarily of extracellular matrix with a sparse population of chondrocytes distributed throughout the tissue. Articular cartilage is composed of chondrocytes, type II collagen fibril meshwork, proteoglycans and water. Active chondrocytes are unique in that they have a relatively low turnover rate and are sparsely distributed within the surrounding matrix. The collagens give the tissue its form and tensile strength and the interaction of proteoglycans with water give the tissue its stiffness to compression, resilience and durability. The hyaline cartilage provides a low friction bearing surface over the bony parts of the joint. If the lining becomes worn or damaged resulting in lesions, joint movement may be painful or severely restricted. Whereas damaged bone typically can regenerate successfully, hyaline cartilage regeneration is quite limited because of it's limited regenerative and reparative abilities. [0005] Articular cartilage lesions generally do not heal, or heal only partially under certain biological conditions due to the lack of nerves, blood vessels and a lymphatic system. The limited reparative capabilities of hyaline cartilage usually results in the generation of repair tissue that lacks the structure and biomechanical properties of normal cartilage. Generally, the healing of the defect results in a fibrocartilaginous repair tissue that lacks the structure and biomedical properties of hyaline cartilage and degrades over the course of time. Articular cartilage lesions are frequently associated with disability and with symptoms such as joint pain, locking phenomena and reduced or disturbed function. These lesions are difficult to treat because of the distinctive structure and function of hyaline cartilage. Such lesions are believed to progress to severe forms of osteoarthritis. Osteoarthritis is the leading cause of disability and impairment in middle-aged and older individuals, entailing significant economic, social and psychological costs. Each year, osteoarthritis accounts for as many as 39 million physician visits and more than 500,000 hospitalizations. By the year 2020, arthritis is expected to affect almost 60 million persons in the United States and to limit the activity of 11.6 million persons. [0006] There are many current therapeutic methods being used. None of these therapies has resulted in the successful regeneration of hyaline-like tissue that withstands normal joint loading and activity over prolonged periods. Currently, the techniques most widely utilized clinically for cartilage defects and degeneration are not articular cartilage substitution procedures, but rather lavage, arthroscopic debridement, and repair stimulation. The direct transplantation of cells or tissue into a defect and the replacement of the defect with biologic or synthetic substitutions presently accounts for only a small percentage of surgical interventions. The optimum surgical goal is to replace the defects with cartilage-like substitutes so as to provide pain relief, reduce effusions and inflammation, restore function, reduce disability and postpone or alleviate the need for prosthetic replacement. [0007] Lavage and arthroscopic debridement involve irrigation of the joint with solutions of sodium chloride, Ringer or Ringer and lactate. The temporary pain relief is believed to result from removing degenerative cartilage debris, proteolytic enzymes and inflammatory mediators. These techniques provide temporary pain relief, but have little or no potential for further healing. [0008] Repair stimulation is conducted by means of drilling, abrasion arthroplasty or microfracture. Penetration into the subchondral bone induces bleeding and fibrin clot formation which promotes initial repair, however, the tissue formed is fibrous in nature and not durable. Pain relief is temporary as the tissue exhibits degeneration, loss of resilience, stiffness and wear characteristics over time. [0009] The periosteum and perichondrium have been shown to contain mesenchymal progenitor cells capable of differentiation and proliferation. They have been used as grafts in both animal and human models to repair articular defects. Few patients over 40 years of age obtained good clinical results, which most likely reflects the decreasing population of osteochondral progenitor cells with increasing age. There have also been problems with adhesion and stability of the grafts, which result in their displacement or loss from the repair site. [0010] Transplantation of cells grown in culture provides another method of introducing a new cell population into chondral and osteochondral defects. Carticel® is a commercial process to culture a patient's own cartilage cells for use in the repair of cartilage defects in the femoral condyle marketed by Genzyme Biosurgery in the United States and Europe. The procedure uses arthroscopy to take a biopsy from a healthy, less loaded area of articular cartilage. Enzymatic digestion of the harvested tissue releases the cells that are sent to a laboratory where they are grown for a period ranging from 2-5 weeks. Once cultivated, the cells are injected during a more open and extensive knee procedure into areas of defective cartilage where it is hoped that they will facilitate the repair of damaged tissue. An autologous periosteal flap with cambium layer is used to seal the transplanted cells in place and act as a mechanical barrier. Fibrin glue is used to seal the edges of the flap. This technique preserves the subchondral bone plate and has reported a high success rate. Proponents of this procedure report that it produces satisfactory results, including the ability to return to demanding physical activities, in more than 90% of patients and that biopsy specimens of the tissue in the graft sites show hyaline-like cartilage repair. More work is needed to assess the function and durability of the new tissue and determine whether it improves joint function and delays or prevents joint degeneration. As with the perichondrial graft, patient/donor age may compromise the success of this procedure as chondrocyte population decreases with increasing age. Disadvantages to this procedure include the need for two separate surgical procedures, potential damage to surrounding cartilage when the periosteal patch is sutured in place, the requirement of demanding microsurgical techniques, and the expensive cost of the procedure which is currently not covered by insurance. [0011] Osteochondral transplantation or mosaicplasty involves excising all injured or unstable tissue from the articular defect and creating cylindrical holes in the base of the defect and underlying bone. These holes are filled with autologous cylindrical plugs of healthy cartilage and bone in a mosaic fashion. The osteochondral plugs are harvested from a lower weight-bearing area of lesser importance in the same joint. This technique, shown in Prior Art FIG. 2 , can be performed as arthroscopic or open procedures. Reports of results of osteochondral plug autografts in a small numbers of patients indicate that they decrease pain and improve joint function, however, long-term results have not been reported. Factors that can compromise the results include donor site morbidity, effects of joint incongruity on the opposing surface of the donor site, damage to the chondrocytes at the articular margins of the donor and recipient sites during preparation and implantation, and collapse or settling of the graft over time. The limited availability of sites for harvest of osteochondral autografts restricts the use of this approach to treatment of relatively small articular defects and the healing of the chondral portion of the autograft to the adjacent articular cartilage remains a concern. [0012] Transplantation of large allografts of bone and overlying articular cartilage is another treatment option that involves a greater area than is suitable for autologous cylindrical plugs, as well as for a non-contained defect. The advantages of osteochondral allografts are the potential to restore the anatomic contour of the joint, lack of morbidity related to graft harvesting, greater availability than autografts and the ability to prepare allografts in any size to reconstruct large defects. Clinical experience with fresh and frozen osteochondral allografts shows that these grafts can decrease joint pain, and that the osseous portion of an allograft can heal to the host bone and the chondral portion can function as an articular surface. Drawbacks associated with this methodology in the clinical situation include the scarcity of fresh donor material and problems connected with the handling and storage of frozen tissue. Fresh allografts carry the risk of immune response or disease transmission. Musculoskeletal Transplant Foundation (MTF) has preserved fresh allografts in a media that maintains a cell viability of 50% for 35 days for use as implants. Frozen allografts lack cell viability and have shown a decreased amount of proteoglycan content which contribute to deterioration of the tissue. [0013] A number of United States Patents have been specifically directed towards bone plugs which are implanted into a bone defect. Examples of such bone plugs are U.S. Pat. No. 4,950,296 issued Aug. 21, 1990 which discloses a bone graft device comprising a cortical shell having a selected outer shape and a cavity formed therein for receiving a cancerous plug, and a cancellous plug fitted into the cavity in a manner to expose at least one surface; U.S. Pat. No. 6,039,762 issued Mar. 21, 2000 having a cylindrical shell with an interior body of deactivated bone material and U.S. Pat. No. 6,398,811 issued Jun. 4, 2002 directed toward a bone spacer which has a cylindrical cortical bone plug with an internal throughgoing bore designed to hold a reinforcing member. U.S. Pat. No. 6,383,211 issued May 7, 2002 discloses an invertebral implant having a substantially cylindrical body with a throughgoing bore dimensioned to receive bone growth materials. [0014] U.S. Pat. No. 6,379,385 issued Apr. 30, 2002 discloses an implant base body of spongious bone material into which a load carrying support element is embedded. The support element can take the shape of a diagonal cross or a plurality of cylindrical pins. See also, U.S. Pat. No. 6,294,187 issued Sep. 25, 2001 which is directed to a load bearing osteoimplant made of compressed bone particles in the form of a cylinder. The cylinder is provided with a plurality of throughgoing bores to promote blood flow through the osteoimplant or to hold a demineralized bone and glycerol paste mixture. U.S. Pat. No. 6,096,081 issued Aug. 1, 2000 shows a bone dowel with a cortical end cap or caps at both ends, a brittle cancerous body and a throughgoing bore. [0015] A number of patents in the prior art show the use of bone putty, pastes or gels to fill bone defects. U.S. Pat. No. 5,290,558 issued Mar. 1, 1994 discloses a flowable demineralized bone powder composition using an osteogenic bone powder with large particle size ranging from about 0.1 to about 1.2 cm mixed with a low molecular weight polyhydroxy compound possessing from 2 to about 18 carbons including a number of classes of different compounds such as monosaccharides, disaccharides, water dispersible oligosaccharides and polysaccharides. [0016] A bone gel is disclosed in the U.S. Pat. No. 5,073,373 issued Dec. 17, 1991. Bone lamellae in the shape of threads or filaments retaining low molecular weight glycerol carrier are disclosed in U.S. Pat. Nos. 5,314,476 issued May 24, 1994 and 5,507,813 issued Apr. 16, 1996 and the tissue forms described in these patents are known commercially as the GRAFTON® Putty and Flex, respectively. [0017] U.S. Pat. No. 5,356,629 issued Oct. 18, 1994 discloses making a rigid gel in the nature of a bone cement to fill defects in bone by mixing biocompatible particles, preferably polymethylmethacrylate coated with polyhydroxyethylmethacrylate in a matrix selected from a group which lists hyaluronic acid to obtain a molded semi-solid mass which can be suitably worked for implantation into bone. The hyaluronic acid can also be utilized in monomeric form or in polymeric form preferably having a molecular weight not greater than about one million Daltons. It is noted that the nonbioabsorbable material which can be used to form the biocompatible particles can be derived from xenograft bone, homologous bone, autogenous bone as well as other materials. The bioactive substance can also be an osteogenic agent such as demineralized bone powder morselized cancerous bone, aspirated bone marrow and other autogenous bone sources. The average size of the particles employed is preferably about 0.1 to about 3.0 mm, more preferably about 0.2 to about 1.5 mm, and most preferably about 0.3 to about 1.0 mm. It is inferentially mentioned but not taught that particles having average sizes of about 7,000 to 8,000 microns, or even as small as about 100 to 700 microns can be used. [0018] U.S. Pat. No. 4,172,128 issued Oct. 23, 1979 discloses a demineralized bone material mixed with a carrier to reconstruct tooth or bone material by adding a mucopolysaccharide to a mineralized bone colloidal material. The composition is formed from a demineralized coarsely ground bone material, which may be derived from human bones and teeth, dissolved in a solvent forming a colloidal solution to which is added a physiologically inert polyhydroxy compound such as mucopolysaccharide or polyuronic acid in an amount which causes orientation when hydrogen ions or polyvalent metal ions are added to form a gel. The gel will be flowable at elevated temperatures above 35° C. and will solidify when brought down to body temperature. Example 25 of the patent notes that mucopolysaccharides produce pronounced ionotropic effects and that hyaluronic acid is particularly responsible for spatial cross-linking. [0019] U.S. Pat. No. 6,030,635 issued Feb. 29, 2000 and U.S. Pat. No. 6,437,018 issued Aug. 20, 2002 are directed toward a malleable bone putty and a flowable gel composition for application to a bone defect site to promote new bone growth at the site which utilize a new bone growth inducing compound of demineralized lyophilized allograft bone powder. The bone powder has a particle size ranging from about 100 to about 850 microns and is mixed in a high molecular weight hydrogel carrier which contains a sodium phosphate saline buffer. [0020] The use of implants for cartilage defects is much more limited. Aside from the fresh allograft implants and autologous implants, U.S. Pat. No. 6,110,209 issued Nov. 5, 1998 shows the use an autologous articular cartilage cancellous bone paste to fill arthritic defects. The surgical technique is arthroscopic and includes debriding (shaving away loose or fragmented articular cartilage), followed by morselizing the base of the arthritic defect with an awl until bleeding occurs. An osteochondral graft is then harvested from the inner rim of the intercondylar notch using a trephine. The graft is then morselized in a bone graft crusher, mixing the articular cartilage with the cancerous bone. The paste is then pushed into the defect and secured by the adhesive properties of the bleeding bone. The paste can also be mixed with a cartilage stimulating factor, a plurality of cells, or a biological glue. All patients are kept non-weight bearing for four weeks and used a continuous passive motion machine for six hours each night. Histologic appearance of the biopsies have mainly shown a mixture of fibrocartilage with hyaline cartilage. Concerns associated with this method are harvest site morbidity and availability, similar to the mosaicplasty method. [0021] U.S. Pat. No. 6,379,367 issued Apr. 30, 2002 discloses a plug with a base membrane, a control plug, and a top membrane which overlies the surface of the cartilage covering the defective area of the joint. SUMMARY OF THE INVENTION [0022] A cartilage allograft construct assembly comprising a plug with a subchondral bone base and cartilage cap for replacing of articular cartilage defects is used together with a milled cartilage in a biocompatible carrier forming a paste or gel which is added to the plug or placed in a bore which has been cut into the patient to remove the lesion defect area. Additives may be applied to the cartilage mixture in order to increase chondrocyte migration and proliferation. Each allograft construct can support the addition of a variety of chondrogenic stimulating factors including, but not limited to growth factors (FGF-2, FGF-5, IGF-1, TGF-β, BMP-2, BMP-7, PDGF, VEGF), human allogenic or autologous chondrocytes, human allogenic or autologous bone marrow cells, stem cells, demineralized bone matrix, insulin, insulin-like growth factor-1, transforming growth factor-B, interleukin-1 receptor antagonist, hepatocyte growth factor, platelet-derived growth factor, Indian hedgehog and parathyroid hormone-related peptide or bioactive glue. BRIEF DESCRIPTION OF THE DRAWINGS [0023] FIG. 1 shows the anatomy of a knee joint; [0024] FIG. 2 shows a schematic mosaicplasty as known in the prior art; [0025] FIG. 3 shows a schematic perspective view of an interference fit cylindrical allograft osteochondral plug assembly in a defect site; [0026] FIG. 4 shows a perspective view of the osteochondral plug used in FIG. 3 ; [0027] FIG. 5 shows a perspective view of a cylindrical interference fit allograft osteochondral plug assembly having throughgoing bores; [0028] FIG. 6 shows a perspective view of the osteochondral plug used in FIG. 5 ; [0029] FIG. 7 shows a schematic perspective view of another embodiment of a mushroom shaped allograft osteochondral assembly in a defect site; [0030] FIG. 8 shows a perspective view of the mushroom shaped osteochondral plug used in FIG. 7 ; and [0031] FIG. 9 shows a perspective view of an osteochondral plug with outside longitudinal channels. DESCRIPTION OF THE INVENTION [0032] The present invention is directed towards a cartilage repair assembly and method of treatment. The preferred embodiment and best mode of the invention is shown in FIGS. 5 and 6 . In the production of the invention, an allograft plug with a cartilage cap and hyaline cartilage are treated to remove cellular material, chondrocytes and pluripotent mesenchymal cells and proteoglycans, freezing same −20° C. to −80° C., and lyophilized reducing its water content. [0033] In the treatment for cell and proteoglycan extraction the allograft cartilage and plugs which were previously harvested from a donor were soaked in hyaluronidase (type IV-s, 3 mg/mL), trypsin (0.25% in monodibasic buffer 3 ml) and the samples were placed in a test tube for 18 hours at 37° C. with sonication. It was found that sonication is not a necessary requirement and the times of soaking vary with concentration of hyaluronidase and trypsin and can be as little as 2 hours. The plug samples were decalcified, washed with DI water and placed in a 50%/50% chloroform/methanol solution for 72 hours to remove cellular debris and sterilize. The above method has been previously used on human tissue and is set forth in the Journal of Rheumatology, 12:4, 1985 by Gust Verbruggen et al., titled “Repair Function in Organ Cultured Human Cartilage Replacement of Enzymatically Removed Proteoglycans During Longterm Organ Culture.” After repeated washes with sterile DI water, the hydrated plug samples and cartilage were frozen at −70° 0 C. and lyophilized to reduce the water content within the range of about 0.1% to about 8.0%. In an alternative usage, the plug samples and cartilage were frozen after processing. [0034] The osteochondral plug 20 which has been treated as noted above is placed in a bore or core 60 which has been cut in the lesion area of the bone 100 of a patient with the upper surface 25 of the cartilage cap 24 being slightly proud or substantially flush with the surface of the original cartilage 102 remaining at the area being treated. The plug 20 has a subchondral bone portion 22 and an overlying integral cartilage cap 24 . The length of the osteochondral plug 20 can be the same as the depth of the bore 60 or less than the depth of the bore 60 . If the plug 20 is the same length, the base of the plug implant is supported and the articular cartilage cap 24 is level with the articular cartilage 102 . If the plug is of a lesser length, the base of the plug implant is not supported but support is provided by the wall of the bore 60 or respective cut out area as the plug is interference fit within the bore or cut out area with the cap being slightly proud or flush with the articular cartilage 102 depending on the surgeon's preference. With such load bearing support the graft surface is not damaged by weight or bearing loads which can cause micromotion interfering with the graft interface producing fibrous tissue interfaces and subchondral cysts. [0035] As shown in FIGS. 3 and 5 the respective plug 20 , 30 has an interference fit within bore 60 . The osteochondral plug, which is generally referred to as a plug in the present description is also envisioned as having various shapes namely; a cylindrical shape 20 , 30 as shown in FIGS. 3-6 , a mushroom shape 40 as shown in FIGS. 7 and 8 , and a channeled or grooved shape 50 as shown in FIG. 9 . [0036] The preferred embodiment is shown in FIGS. 5 and 6 and has a cylindrical body 30 with a subchondral bone portion 32 and an overlying cartilage cap 34 . A plurality of throughgoing bores 36 are drilled through the bone portion 32 and cap 34 to allow cell migration from a cartilage mixture which has been placed in the bore to promote cartilage growth. The cartilage mixture is more fully described later in the description of the invention. [0037] Another embodiment is a mushroom shaped configuration 40 as is shown in FIGS. 7 and 8 which has a cylindrical subchondral bone portion 42 and an overlying larger diameter cartilage cap 44 . The cap 44 is larger in diameter than the body 42 and the periphery 47 of the cap extends past the cylindrical wall 43 of the body. If the cap 44 is the same size as the bore 60 then the body 42 has a length which will engage the floor of the bore 60 so that the cap 44 upper cartilage surface 45 is flush with the upper surface of the surrounding cartilage area 102 . Alternately, a second stepped cut 61 may be made in the cartilage surface area down to the depth of the bottom of the cartilage layer which will support the base or lower extending surface 46 of the cap cartilage so that it is flush with the surrounding cartilage area 102 with the lower smaller diameter of the bore 62 being substantially the same as the diameter of the subchondral bone portion with the plug being held therein in an interference fit. [0038] As shown in FIG. 9 the exterior surface of the implant 50 may be formed with grooves or channels 52 which can run longitudinally along the outside surface of the implant or alternatively just along the surface of the subchondral bone portion 22 , 32 , 42 ending at the bottom surface of the cartilage cap 24 , 34 , 44 overlying same. This variation of FIG. 9 also has an interference fit with the wall of the bore 62 . [0039] In operation the lesion or defect is removed by cutting a bore 60 or removing a lesion in the implant area 100 and filling the bore 60 or cut away area with a desired amount of a milled cartilage mixture and a biological carrier such as sodium hyaluronate, hyaluronic acid and its derivatives, gelatin, collagen, chitosan, alginate, buffered PBS, Dextran, or polymers and one or more additives namely chondrogenic stimulating factors including, but not limited to growth factors (FGF-2, FGF-5, IGF-1, TGF-β, BMP-2, BMP-7PDGF, VEGF), human allogenic or autologous chondrocytes, human allogenic cells, human allogenic or autologous bone marrow cells, human allogenic or autologous stem cells, demineralized bone matrix, insulin, insulin-like growth factor-1, interleukin-1 receptor antagonist, hepatocyte growth factor, platelet-derived growth factor, Indian hedgehog and parathyroid hormone-related peptide. Depending upon the weight of the milled cartilage as noted in Examples 2 and 3 below, the mixture will have the consistency of a paste or gel. The plug 20 is then placed in the bore or cut away area in an interface fit with the surrounding walls. [0040] Suitable organic glue material can be used to keep the implant fixed in place in the implant area. Suitable organic glue material can be found commercially, such as for example; TISSEEL® or TISSUCOL® (fibrin based adhesive; Immuno AG, Austria), Adhesive Protein (Sigma Chemical, USA), Dow Corning Medical Adhesive B (Dow Corning, USA), fibrinogen thrombin, elastin, collagen, casein, albumin, keratin and the like. EXAMPLE 1 [0041] A non-viable or decellularized osteochondral plug consisting of a subchondral bone base and overlying cartilage cap was treated with a solution or variety of solutions to remove the cellular debris as well as the proteoglycans as noted in the treatment described above. It is believed that this removal provides signaling to stimulate the surrounding chondrocytes to proliferate and form new proteoglycans and other factors producing new matrix. The diameter or diagonal of the plug ranges from 1 mm to 30 mm but is preferably 4 mm to 10 mm which is small enough to fit through the endoscopic cannula, but large enough to minimize the number of plugs needed to fill large defects. This size provides good results at the recipient site and provides a more confluent hyaline surface. The thickness of subchondral bone can be modified to match the anatomy of the patient so that the surface cartilage of the plug will be even with and follow the surface contour of the surface cartilage of the host tissue. The treated plug also creates a more porous matrix, which allows more cells to enter. The plug and minced hyaline cartilage can be stored frozen or freeze dried and support any of the mentioned chondrogenic stimulating factors. The plug can be inserted arthroscopically similar to the mosaicplasty procedure or through an open incision. The plug and cartilage material can be made in various dimensions depending on the size of the defect being treated. [0042] This design uses the allograft cartilage putty or gel as noted below in a prepackaged amount to provide cartilage cell growth for the osteochondral plug. The putty or gel enhances the tissue integration between the plug and host tissue. [0043] The base of the bore or cut away area is provided with a matrix of minced cartilage putty consisting of minced or milled allograft cartilage which has been lyophilized so that its water content ranges from 0.1% to 8.0% ranging from 25% to 50% by weight, mixed with a carrier of sodium hyaluronate solution (HA) (molecular weight ranging from 7.0×10 5 to 1.2×10 6 or any other bioabsorbable carrier such as hyaluronic acid and its derivatives, gelatin, collagen, chitosan, alginate, buffered PBS, Dextran, or polymers, the carrier ranging from ranging from 75% to 50% by weight. The cartilage is milled to a size ranging up to 1 mm. [0044] In gel form, the minced cartilage has been lyophilized so that its water content ranges from 0.1% to 8.0%, ranging from 15% to 30% by weight and the carrier ranges from 85% to 70% by weight. The particle size of the cartilage when milled is less than or equal to 1 mm dry. The cartilage pieces can be processed to varying particle sizes and the HA or other carrier can have different viscosities depending on the desired consistency of the putty or gel. This cartilage matrix can be deposited into the cartilage defect arthroscopically and fit into the defect where it is held in place by the implant which is placed over it as a cap. [0045] Cells which have been grown outside the patient are inserted by syringe into the matrix before, during or after deposit of the cartilage matrix into the defect area. Such cells include allogenic or autologous, bone marrow cells, stem cells and chondrocyte cells. The cellular density of the cells preferably ranges from 1.0×10 8 to 5.0×10 8 or from about 100 million to about 500 million cells per cc of putty or gel mixture. This composite material can be injected into the cartilage defect arthroscopically as previously noted. This matrix can support the previously mentioned chondrogenic stimulating factors. [0046] The operation of placing the cartilage defect assembly in a cartilage defect, comprises (a) drilling a cylindrical hole in a patient at a site of a cartilage defect to remove the diseased area of cartilage; (b) placing a mixture of milled allograft cartilage in a bioabsorbable carrier in the drilled cylindrical hole; and (c) placing the pretreated implant in the bore over the mixture of the inserted milled allograft cartilage in a bioabsorbable carrier in interference with the wall of the bore to contain the mixture in the cylindrical hole for a predetermined period of time to promote cartilage growth at the defect site. [0047] When using the mushroom shaped embodiment of FIGS. 7 and 8 a second larger diameter bore is cut into the bone around the first bore and the cartilage layer is removed to present a stepped bore forming a seat upon which the lower surface of the overlying portion of the cartilage cap is seated. [0048] The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. However, the invention should not be construed as limited to the particular embodiments which have been described above. Instead, the embodiments described here should be regarded as illustrative rather than restrictive. Variations and changes may be made by others without departing from the scope of the present invention as defined by the following claims:
The invention is directed toward a cartilage repair assembly comprising a shaped allograft structure of subchondral bone with an integral overlying cartilage cap which is treated to remove cellular debris and proteoglycans and milled allograft cartilage in a bioabsorbable carrier. The shaped structure is dimensioned to fit in a drilled bore in a cartilage defect area so that either the shaped bone or the cartilage cap engage the side wall of the drilled bore in an interference fit and is in contact with a milled cartilage and biocompatible carrier mixture allowing cell transfer throughout the defect area. A method for inserting the shaped allograft structure into a cartilage defect area is also disclosed.
Identify and summarize the most critical technical features from the given patent document.
[ "RELATED APPLICATION [0001] This application is a continuation of U.S. patent application Ser.", "No. 10/438,883 filed May 16, 2003, which is incorporated by reference herein in its entirety.", "FIELD OF INVENTION [0002] The present invention is generally directed toward an implant and is more specifically directed toward an allograft implant having a cartilage face and bone body which has been treated to remove cellular debris and proteoglycans and is shaped for an interference fit implantation in a shoulder or knee joint.", "The implant is provided with channels which allow transport of cellular materials throughout the implant site to stimulate cartilage growth BACKGROUND OF THE INVENTION [0003] Articular cartilage injury and degeneration present medical problems to the general population which are constantly addressed by orthopedic surgeons.", "Every year in the United States, over 500,000 arthroplastic or joint repair procedures are performed.", "These include approximately 125,000 total hip and 150,000 total knee arthroplastics and over 41,000 open arthroscopic procedures to repair cartilaginous defects of the knee.", "[0004] In the knee joint, the articular cartilage tissue forms a lining which faces the joint cavity on one side and is linked to the subchondral bone plate by a narrow layer of calcified cartilage tissue on the other.", "Articular cartilage (hyaline cartilage) consists primarily of extracellular matrix with a sparse population of chondrocytes distributed throughout the tissue.", "Articular cartilage is composed of chondrocytes, type II collagen fibril meshwork, proteoglycans and water.", "Active chondrocytes are unique in that they have a relatively low turnover rate and are sparsely distributed within the surrounding matrix.", "The collagens give the tissue its form and tensile strength and the interaction of proteoglycans with water give the tissue its stiffness to compression, resilience and durability.", "The hyaline cartilage provides a low friction bearing surface over the bony parts of the joint.", "If the lining becomes worn or damaged resulting in lesions, joint movement may be painful or severely restricted.", "Whereas damaged bone typically can regenerate successfully, hyaline cartilage regeneration is quite limited because of it's limited regenerative and reparative abilities.", "[0005] Articular cartilage lesions generally do not heal, or heal only partially under certain biological conditions due to the lack of nerves, blood vessels and a lymphatic system.", "The limited reparative capabilities of hyaline cartilage usually results in the generation of repair tissue that lacks the structure and biomechanical properties of normal cartilage.", "Generally, the healing of the defect results in a fibrocartilaginous repair tissue that lacks the structure and biomedical properties of hyaline cartilage and degrades over the course of time.", "Articular cartilage lesions are frequently associated with disability and with symptoms such as joint pain, locking phenomena and reduced or disturbed function.", "These lesions are difficult to treat because of the distinctive structure and function of hyaline cartilage.", "Such lesions are believed to progress to severe forms of osteoarthritis.", "Osteoarthritis is the leading cause of disability and impairment in middle-aged and older individuals, entailing significant economic, social and psychological costs.", "Each year, osteoarthritis accounts for as many as 39 million physician visits and more than 500,000 hospitalizations.", "By the year 2020, arthritis is expected to affect almost 60 million persons in the United States and to limit the activity of 11.6 million persons.", "[0006] There are many current therapeutic methods being used.", "None of these therapies has resulted in the successful regeneration of hyaline-like tissue that withstands normal joint loading and activity over prolonged periods.", "Currently, the techniques most widely utilized clinically for cartilage defects and degeneration are not articular cartilage substitution procedures, but rather lavage, arthroscopic debridement, and repair stimulation.", "The direct transplantation of cells or tissue into a defect and the replacement of the defect with biologic or synthetic substitutions presently accounts for only a small percentage of surgical interventions.", "The optimum surgical goal is to replace the defects with cartilage-like substitutes so as to provide pain relief, reduce effusions and inflammation, restore function, reduce disability and postpone or alleviate the need for prosthetic replacement.", "[0007] Lavage and arthroscopic debridement involve irrigation of the joint with solutions of sodium chloride, Ringer or Ringer and lactate.", "The temporary pain relief is believed to result from removing degenerative cartilage debris, proteolytic enzymes and inflammatory mediators.", "These techniques provide temporary pain relief, but have little or no potential for further healing.", "[0008] Repair stimulation is conducted by means of drilling, abrasion arthroplasty or microfracture.", "Penetration into the subchondral bone induces bleeding and fibrin clot formation which promotes initial repair, however, the tissue formed is fibrous in nature and not durable.", "Pain relief is temporary as the tissue exhibits degeneration, loss of resilience, stiffness and wear characteristics over time.", "[0009] The periosteum and perichondrium have been shown to contain mesenchymal progenitor cells capable of differentiation and proliferation.", "They have been used as grafts in both animal and human models to repair articular defects.", "Few patients over 40 years of age obtained good clinical results, which most likely reflects the decreasing population of osteochondral progenitor cells with increasing age.", "There have also been problems with adhesion and stability of the grafts, which result in their displacement or loss from the repair site.", "[0010] Transplantation of cells grown in culture provides another method of introducing a new cell population into chondral and osteochondral defects.", "Carticel® is a commercial process to culture a patient's own cartilage cells for use in the repair of cartilage defects in the femoral condyle marketed by Genzyme Biosurgery in the United States and Europe.", "The procedure uses arthroscopy to take a biopsy from a healthy, less loaded area of articular cartilage.", "Enzymatic digestion of the harvested tissue releases the cells that are sent to a laboratory where they are grown for a period ranging from 2-5 weeks.", "Once cultivated, the cells are injected during a more open and extensive knee procedure into areas of defective cartilage where it is hoped that they will facilitate the repair of damaged tissue.", "An autologous periosteal flap with cambium layer is used to seal the transplanted cells in place and act as a mechanical barrier.", "Fibrin glue is used to seal the edges of the flap.", "This technique preserves the subchondral bone plate and has reported a high success rate.", "Proponents of this procedure report that it produces satisfactory results, including the ability to return to demanding physical activities, in more than 90% of patients and that biopsy specimens of the tissue in the graft sites show hyaline-like cartilage repair.", "More work is needed to assess the function and durability of the new tissue and determine whether it improves joint function and delays or prevents joint degeneration.", "As with the perichondrial graft, patient/donor age may compromise the success of this procedure as chondrocyte population decreases with increasing age.", "Disadvantages to this procedure include the need for two separate surgical procedures, potential damage to surrounding cartilage when the periosteal patch is sutured in place, the requirement of demanding microsurgical techniques, and the expensive cost of the procedure which is currently not covered by insurance.", "[0011] Osteochondral transplantation or mosaicplasty involves excising all injured or unstable tissue from the articular defect and creating cylindrical holes in the base of the defect and underlying bone.", "These holes are filled with autologous cylindrical plugs of healthy cartilage and bone in a mosaic fashion.", "The osteochondral plugs are harvested from a lower weight-bearing area of lesser importance in the same joint.", "This technique, shown in Prior Art FIG. 2 , can be performed as arthroscopic or open procedures.", "Reports of results of osteochondral plug autografts in a small numbers of patients indicate that they decrease pain and improve joint function, however, long-term results have not been reported.", "Factors that can compromise the results include donor site morbidity, effects of joint incongruity on the opposing surface of the donor site, damage to the chondrocytes at the articular margins of the donor and recipient sites during preparation and implantation, and collapse or settling of the graft over time.", "The limited availability of sites for harvest of osteochondral autografts restricts the use of this approach to treatment of relatively small articular defects and the healing of the chondral portion of the autograft to the adjacent articular cartilage remains a concern.", "[0012] Transplantation of large allografts of bone and overlying articular cartilage is another treatment option that involves a greater area than is suitable for autologous cylindrical plugs, as well as for a non-contained defect.", "The advantages of osteochondral allografts are the potential to restore the anatomic contour of the joint, lack of morbidity related to graft harvesting, greater availability than autografts and the ability to prepare allografts in any size to reconstruct large defects.", "Clinical experience with fresh and frozen osteochondral allografts shows that these grafts can decrease joint pain, and that the osseous portion of an allograft can heal to the host bone and the chondral portion can function as an articular surface.", "Drawbacks associated with this methodology in the clinical situation include the scarcity of fresh donor material and problems connected with the handling and storage of frozen tissue.", "Fresh allografts carry the risk of immune response or disease transmission.", "Musculoskeletal Transplant Foundation (MTF) has preserved fresh allografts in a media that maintains a cell viability of 50% for 35 days for use as implants.", "Frozen allografts lack cell viability and have shown a decreased amount of proteoglycan content which contribute to deterioration of the tissue.", "[0013] A number of United States Patents have been specifically directed towards bone plugs which are implanted into a bone defect.", "Examples of such bone plugs are U.S. Pat. No. 4,950,296 issued Aug. 21, 1990 which discloses a bone graft device comprising a cortical shell having a selected outer shape and a cavity formed therein for receiving a cancerous plug, and a cancellous plug fitted into the cavity in a manner to expose at least one surface;", "U.S. Pat. No. 6,039,762 issued Mar. 21, 2000 having a cylindrical shell with an interior body of deactivated bone material and U.S. Pat. No. 6,398,811 issued Jun. 4, 2002 directed toward a bone spacer which has a cylindrical cortical bone plug with an internal throughgoing bore designed to hold a reinforcing member.", "U.S. Pat. No. 6,383,211 issued May 7, 2002 discloses an invertebral implant having a substantially cylindrical body with a throughgoing bore dimensioned to receive bone growth materials.", "[0014] U.S. Pat. No. 6,379,385 issued Apr. 30, 2002 discloses an implant base body of spongious bone material into which a load carrying support element is embedded.", "The support element can take the shape of a diagonal cross or a plurality of cylindrical pins.", "See also, U.S. Pat. No. 6,294,187 issued Sep. 25, 2001 which is directed to a load bearing osteoimplant made of compressed bone particles in the form of a cylinder.", "The cylinder is provided with a plurality of throughgoing bores to promote blood flow through the osteoimplant or to hold a demineralized bone and glycerol paste mixture.", "U.S. Pat. No. 6,096,081 issued Aug. 1, 2000 shows a bone dowel with a cortical end cap or caps at both ends, a brittle cancerous body and a throughgoing bore.", "[0015] A number of patents in the prior art show the use of bone putty, pastes or gels to fill bone defects.", "U.S. Pat. No. 5,290,558 issued Mar. 1, 1994 discloses a flowable demineralized bone powder composition using an osteogenic bone powder with large particle size ranging from about 0.1 to about 1.2 cm mixed with a low molecular weight polyhydroxy compound possessing from 2 to about 18 carbons including a number of classes of different compounds such as monosaccharides, disaccharides, water dispersible oligosaccharides and polysaccharides.", "[0016] A bone gel is disclosed in the U.S. Pat. No. 5,073,373 issued Dec. 17, 1991.", "Bone lamellae in the shape of threads or filaments retaining low molecular weight glycerol carrier are disclosed in U.S. Pat. Nos. 5,314,476 issued May 24, 1994 and 5,507,813 issued Apr. 16, 1996 and the tissue forms described in these patents are known commercially as the GRAFTON® Putty and Flex, respectively.", "[0017] U.S. Pat. No. 5,356,629 issued Oct. 18, 1994 discloses making a rigid gel in the nature of a bone cement to fill defects in bone by mixing biocompatible particles, preferably polymethylmethacrylate coated with polyhydroxyethylmethacrylate in a matrix selected from a group which lists hyaluronic acid to obtain a molded semi-solid mass which can be suitably worked for implantation into bone.", "The hyaluronic acid can also be utilized in monomeric form or in polymeric form preferably having a molecular weight not greater than about one million Daltons.", "It is noted that the nonbioabsorbable material which can be used to form the biocompatible particles can be derived from xenograft bone, homologous bone, autogenous bone as well as other materials.", "The bioactive substance can also be an osteogenic agent such as demineralized bone powder morselized cancerous bone, aspirated bone marrow and other autogenous bone sources.", "The average size of the particles employed is preferably about 0.1 to about 3.0 mm, more preferably about 0.2 to about 1.5 mm, and most preferably about 0.3 to about 1.0 mm.", "It is inferentially mentioned but not taught that particles having average sizes of about 7,000 to 8,000 microns, or even as small as about 100 to 700 microns can be used.", "[0018] U.S. Pat. No. 4,172,128 issued Oct. 23, 1979 discloses a demineralized bone material mixed with a carrier to reconstruct tooth or bone material by adding a mucopolysaccharide to a mineralized bone colloidal material.", "The composition is formed from a demineralized coarsely ground bone material, which may be derived from human bones and teeth, dissolved in a solvent forming a colloidal solution to which is added a physiologically inert polyhydroxy compound such as mucopolysaccharide or polyuronic acid in an amount which causes orientation when hydrogen ions or polyvalent metal ions are added to form a gel.", "The gel will be flowable at elevated temperatures above 35° C. and will solidify when brought down to body temperature.", "Example 25 of the patent notes that mucopolysaccharides produce pronounced ionotropic effects and that hyaluronic acid is particularly responsible for spatial cross-linking.", "[0019] U.S. Pat. No. 6,030,635 issued Feb. 29, 2000 and U.S. Pat. No. 6,437,018 issued Aug. 20, 2002 are directed toward a malleable bone putty and a flowable gel composition for application to a bone defect site to promote new bone growth at the site which utilize a new bone growth inducing compound of demineralized lyophilized allograft bone powder.", "The bone powder has a particle size ranging from about 100 to about 850 microns and is mixed in a high molecular weight hydrogel carrier which contains a sodium phosphate saline buffer.", "[0020] The use of implants for cartilage defects is much more limited.", "Aside from the fresh allograft implants and autologous implants, U.S. Pat. No. 6,110,209 issued Nov. 5, 1998 shows the use an autologous articular cartilage cancellous bone paste to fill arthritic defects.", "The surgical technique is arthroscopic and includes debriding (shaving away loose or fragmented articular cartilage), followed by morselizing the base of the arthritic defect with an awl until bleeding occurs.", "An osteochondral graft is then harvested from the inner rim of the intercondylar notch using a trephine.", "The graft is then morselized in a bone graft crusher, mixing the articular cartilage with the cancerous bone.", "The paste is then pushed into the defect and secured by the adhesive properties of the bleeding bone.", "The paste can also be mixed with a cartilage stimulating factor, a plurality of cells, or a biological glue.", "All patients are kept non-weight bearing for four weeks and used a continuous passive motion machine for six hours each night.", "Histologic appearance of the biopsies have mainly shown a mixture of fibrocartilage with hyaline cartilage.", "Concerns associated with this method are harvest site morbidity and availability, similar to the mosaicplasty method.", "[0021] U.S. Pat. No. 6,379,367 issued Apr. 30, 2002 discloses a plug with a base membrane, a control plug, and a top membrane which overlies the surface of the cartilage covering the defective area of the joint.", "SUMMARY OF THE INVENTION [0022] A cartilage allograft construct assembly comprising a plug with a subchondral bone base and cartilage cap for replacing of articular cartilage defects is used together with a milled cartilage in a biocompatible carrier forming a paste or gel which is added to the plug or placed in a bore which has been cut into the patient to remove the lesion defect area.", "Additives may be applied to the cartilage mixture in order to increase chondrocyte migration and proliferation.", "Each allograft construct can support the addition of a variety of chondrogenic stimulating factors including, but not limited to growth factors (FGF-2, FGF-5, IGF-1, TGF-β, BMP-2, BMP-7, PDGF, VEGF), human allogenic or autologous chondrocytes, human allogenic or autologous bone marrow cells, stem cells, demineralized bone matrix, insulin, insulin-like growth factor-1, transforming growth factor-B, interleukin-1 receptor antagonist, hepatocyte growth factor, platelet-derived growth factor, Indian hedgehog and parathyroid hormone-related peptide or bioactive glue.", "BRIEF DESCRIPTION OF THE DRAWINGS [0023] FIG. 1 shows the anatomy of a knee joint;", "[0024] FIG. 2 shows a schematic mosaicplasty as known in the prior art;", "[0025] FIG. 3 shows a schematic perspective view of an interference fit cylindrical allograft osteochondral plug assembly in a defect site;", "[0026] FIG. 4 shows a perspective view of the osteochondral plug used in FIG. 3 ;", "[0027] FIG. 5 shows a perspective view of a cylindrical interference fit allograft osteochondral plug assembly having throughgoing bores;", "[0028] FIG. 6 shows a perspective view of the osteochondral plug used in FIG. 5 ;", "[0029] FIG. 7 shows a schematic perspective view of another embodiment of a mushroom shaped allograft osteochondral assembly in a defect site;", "[0030] FIG. 8 shows a perspective view of the mushroom shaped osteochondral plug used in FIG. 7 ;", "and [0031] FIG. 9 shows a perspective view of an osteochondral plug with outside longitudinal channels.", "DESCRIPTION OF THE INVENTION [0032] The present invention is directed towards a cartilage repair assembly and method of treatment.", "The preferred embodiment and best mode of the invention is shown in FIGS. 5 and 6 .", "In the production of the invention, an allograft plug with a cartilage cap and hyaline cartilage are treated to remove cellular material, chondrocytes and pluripotent mesenchymal cells and proteoglycans, freezing same −20° C. to −80° C., and lyophilized reducing its water content.", "[0033] In the treatment for cell and proteoglycan extraction the allograft cartilage and plugs which were previously harvested from a donor were soaked in hyaluronidase (type IV-s, 3 mg/mL), trypsin (0.25% in monodibasic buffer 3 ml) and the samples were placed in a test tube for 18 hours at 37° C. with sonication.", "It was found that sonication is not a necessary requirement and the times of soaking vary with concentration of hyaluronidase and trypsin and can be as little as 2 hours.", "The plug samples were decalcified, washed with DI water and placed in a 50%/50% chloroform/methanol solution for 72 hours to remove cellular debris and sterilize.", "The above method has been previously used on human tissue and is set forth in the Journal of Rheumatology, 12:4, 1985 by Gust Verbruggen et al.", ", titled “Repair Function in Organ Cultured Human Cartilage Replacement of Enzymatically Removed Proteoglycans During Longterm Organ Culture.”", "After repeated washes with sterile DI water, the hydrated plug samples and cartilage were frozen at −70° 0 C. and lyophilized to reduce the water content within the range of about 0.1% to about 8.0%.", "In an alternative usage, the plug samples and cartilage were frozen after processing.", "[0034] The osteochondral plug 20 which has been treated as noted above is placed in a bore or core 60 which has been cut in the lesion area of the bone 100 of a patient with the upper surface 25 of the cartilage cap 24 being slightly proud or substantially flush with the surface of the original cartilage 102 remaining at the area being treated.", "The plug 20 has a subchondral bone portion 22 and an overlying integral cartilage cap 24 .", "The length of the osteochondral plug 20 can be the same as the depth of the bore 60 or less than the depth of the bore 60 .", "If the plug 20 is the same length, the base of the plug implant is supported and the articular cartilage cap 24 is level with the articular cartilage 102 .", "If the plug is of a lesser length, the base of the plug implant is not supported but support is provided by the wall of the bore 60 or respective cut out area as the plug is interference fit within the bore or cut out area with the cap being slightly proud or flush with the articular cartilage 102 depending on the surgeon's preference.", "With such load bearing support the graft surface is not damaged by weight or bearing loads which can cause micromotion interfering with the graft interface producing fibrous tissue interfaces and subchondral cysts.", "[0035] As shown in FIGS. 3 and 5 the respective plug 20 , 30 has an interference fit within bore 60 .", "The osteochondral plug, which is generally referred to as a plug in the present description is also envisioned as having various shapes namely;", "a cylindrical shape 20 , 30 as shown in FIGS. 3-6 , a mushroom shape 40 as shown in FIGS. 7 and 8 , and a channeled or grooved shape 50 as shown in FIG. 9 .", "[0036] The preferred embodiment is shown in FIGS. 5 and 6 and has a cylindrical body 30 with a subchondral bone portion 32 and an overlying cartilage cap 34 .", "A plurality of throughgoing bores 36 are drilled through the bone portion 32 and cap 34 to allow cell migration from a cartilage mixture which has been placed in the bore to promote cartilage growth.", "The cartilage mixture is more fully described later in the description of the invention.", "[0037] Another embodiment is a mushroom shaped configuration 40 as is shown in FIGS. 7 and 8 which has a cylindrical subchondral bone portion 42 and an overlying larger diameter cartilage cap 44 .", "The cap 44 is larger in diameter than the body 42 and the periphery 47 of the cap extends past the cylindrical wall 43 of the body.", "If the cap 44 is the same size as the bore 60 then the body 42 has a length which will engage the floor of the bore 60 so that the cap 44 upper cartilage surface 45 is flush with the upper surface of the surrounding cartilage area 102 .", "Alternately, a second stepped cut 61 may be made in the cartilage surface area down to the depth of the bottom of the cartilage layer which will support the base or lower extending surface 46 of the cap cartilage so that it is flush with the surrounding cartilage area 102 with the lower smaller diameter of the bore 62 being substantially the same as the diameter of the subchondral bone portion with the plug being held therein in an interference fit.", "[0038] As shown in FIG. 9 the exterior surface of the implant 50 may be formed with grooves or channels 52 which can run longitudinally along the outside surface of the implant or alternatively just along the surface of the subchondral bone portion 22 , 32 , 42 ending at the bottom surface of the cartilage cap 24 , 34 , 44 overlying same.", "This variation of FIG. 9 also has an interference fit with the wall of the bore 62 .", "[0039] In operation the lesion or defect is removed by cutting a bore 60 or removing a lesion in the implant area 100 and filling the bore 60 or cut away area with a desired amount of a milled cartilage mixture and a biological carrier such as sodium hyaluronate, hyaluronic acid and its derivatives, gelatin, collagen, chitosan, alginate, buffered PBS, Dextran, or polymers and one or more additives namely chondrogenic stimulating factors including, but not limited to growth factors (FGF-2, FGF-5, IGF-1, TGF-β, BMP-2, BMP-7PDGF, VEGF), human allogenic or autologous chondrocytes, human allogenic cells, human allogenic or autologous bone marrow cells, human allogenic or autologous stem cells, demineralized bone matrix, insulin, insulin-like growth factor-1, interleukin-1 receptor antagonist, hepatocyte growth factor, platelet-derived growth factor, Indian hedgehog and parathyroid hormone-related peptide.", "Depending upon the weight of the milled cartilage as noted in Examples 2 and 3 below, the mixture will have the consistency of a paste or gel.", "The plug 20 is then placed in the bore or cut away area in an interface fit with the surrounding walls.", "[0040] Suitable organic glue material can be used to keep the implant fixed in place in the implant area.", "Suitable organic glue material can be found commercially, such as for example;", "TISSEEL® or TISSUCOL® (fibrin based adhesive;", "Immuno AG, Austria), Adhesive Protein (Sigma Chemical, USA), Dow Corning Medical Adhesive B (Dow Corning, USA), fibrinogen thrombin, elastin, collagen, casein, albumin, keratin and the like.", "EXAMPLE 1 [0041] A non-viable or decellularized osteochondral plug consisting of a subchondral bone base and overlying cartilage cap was treated with a solution or variety of solutions to remove the cellular debris as well as the proteoglycans as noted in the treatment described above.", "It is believed that this removal provides signaling to stimulate the surrounding chondrocytes to proliferate and form new proteoglycans and other factors producing new matrix.", "The diameter or diagonal of the plug ranges from 1 mm to 30 mm but is preferably 4 mm to 10 mm which is small enough to fit through the endoscopic cannula, but large enough to minimize the number of plugs needed to fill large defects.", "This size provides good results at the recipient site and provides a more confluent hyaline surface.", "The thickness of subchondral bone can be modified to match the anatomy of the patient so that the surface cartilage of the plug will be even with and follow the surface contour of the surface cartilage of the host tissue.", "The treated plug also creates a more porous matrix, which allows more cells to enter.", "The plug and minced hyaline cartilage can be stored frozen or freeze dried and support any of the mentioned chondrogenic stimulating factors.", "The plug can be inserted arthroscopically similar to the mosaicplasty procedure or through an open incision.", "The plug and cartilage material can be made in various dimensions depending on the size of the defect being treated.", "[0042] This design uses the allograft cartilage putty or gel as noted below in a prepackaged amount to provide cartilage cell growth for the osteochondral plug.", "The putty or gel enhances the tissue integration between the plug and host tissue.", "[0043] The base of the bore or cut away area is provided with a matrix of minced cartilage putty consisting of minced or milled allograft cartilage which has been lyophilized so that its water content ranges from 0.1% to 8.0% ranging from 25% to 50% by weight, mixed with a carrier of sodium hyaluronate solution (HA) (molecular weight ranging from 7.0×10 5 to 1.2×10 6 or any other bioabsorbable carrier such as hyaluronic acid and its derivatives, gelatin, collagen, chitosan, alginate, buffered PBS, Dextran, or polymers, the carrier ranging from ranging from 75% to 50% by weight.", "The cartilage is milled to a size ranging up to 1 mm.", "[0044] In gel form, the minced cartilage has been lyophilized so that its water content ranges from 0.1% to 8.0%, ranging from 15% to 30% by weight and the carrier ranges from 85% to 70% by weight.", "The particle size of the cartilage when milled is less than or equal to 1 mm dry.", "The cartilage pieces can be processed to varying particle sizes and the HA or other carrier can have different viscosities depending on the desired consistency of the putty or gel.", "This cartilage matrix can be deposited into the cartilage defect arthroscopically and fit into the defect where it is held in place by the implant which is placed over it as a cap.", "[0045] Cells which have been grown outside the patient are inserted by syringe into the matrix before, during or after deposit of the cartilage matrix into the defect area.", "Such cells include allogenic or autologous, bone marrow cells, stem cells and chondrocyte cells.", "The cellular density of the cells preferably ranges from 1.0×10 8 to 5.0×10 8 or from about 100 million to about 500 million cells per cc of putty or gel mixture.", "This composite material can be injected into the cartilage defect arthroscopically as previously noted.", "This matrix can support the previously mentioned chondrogenic stimulating factors.", "[0046] The operation of placing the cartilage defect assembly in a cartilage defect, comprises (a) drilling a cylindrical hole in a patient at a site of a cartilage defect to remove the diseased area of cartilage;", "(b) placing a mixture of milled allograft cartilage in a bioabsorbable carrier in the drilled cylindrical hole;", "and (c) placing the pretreated implant in the bore over the mixture of the inserted milled allograft cartilage in a bioabsorbable carrier in interference with the wall of the bore to contain the mixture in the cylindrical hole for a predetermined period of time to promote cartilage growth at the defect site.", "[0047] When using the mushroom shaped embodiment of FIGS. 7 and 8 a second larger diameter bore is cut into the bone around the first bore and the cartilage layer is removed to present a stepped bore forming a seat upon which the lower surface of the overlying portion of the cartilage cap is seated.", "[0048] The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification.", "However, the invention should not be construed as limited to the particular embodiments which have been described above.", "Instead, the embodiments described here should be regarded as illustrative rather than restrictive.", "Variations and changes may be made by others without departing from the scope of the present invention as defined by the following claims:" ]
This is a divisional application of U.S. Ser. No. 07/677,029 filed Mar. 28, 1991, now U.S. Pat. No. 5,070,093, which is a divisional application of U.S. Ser. No. 07/565,306 filed Aug. 9, 1990, now U.S. Pat. No. 5,109,136. BACKGROUND OF THE INVENTION Excessive excitation by neurotransmitters can cause the degeneration and death of neurons. It is believed that this degeneration is in part mediated by the excitotoxic actions of glutamate and aspartate at the N-methyl-D-aspartate (NMDA) receptor. This excitotoxic action is responsible for the loss of neurons in cerebrovascular disorders such as: cerebral ischemia or cerebral infraction resulting from a range of conditions such as thromboembolic or hemorrhagic stroke, cerebral vasospasm, hypoglycemia, cardiac arrest, status epilepticus, perinatal asphyxia, cerebral trauma and anoxia (such as from drowning and pulmonary surgery). There are no specific therapies for these neurodegenerative diseases, however, compounds which act specifically as antagonists of the NMDA receptor complex, either competitively or noncompetitively, offer a novel therapeutic approach to these disorders: R. Schwarcz and B. Meldrum, The Lancet 140 (1985); B. Meldrum in "Neurotoxins and Their Pharmacological Implications" edited by P. Jenner, Raven Press, New York (1987); D. W. Choi, Neuron 1:623 (1988). Confirmation of the protective effects of noncompetitve NMDA antagonists in various pharmacological models of neurodegenerative disorders have appeared in the literature: J. W. McDonald, F. S. Silverstein, and M. V. Johnston, Eur. J. Pharmocol. 140:359 (1987); R. Gill, A. C. Foster, and G. N. Woodruff, J. Neurosci. 7:3343 (1987); S. M. Rothman, J. H. Thurston, R. E. Hauhart, G. D. Clark, and J. S. Soloman, Neurosci. 21:673 (1987); M. P. Goldbert, P-C. Pham, and D. W. Choi, Neurosci. Lett. 80:11 (1987); L. F. Copeland, P. A. Boxer, and F. W. Marcoux, Soc. Neurosci. Abstr. 14 (part 1):420 (1988); J. A. Kemp, A. C. Foster, R. Gill, and G. N. Woodruff, TIPS 8:414 (1987); R. Gill, A. C. Foster, and G. N. Woodruff, J. Neurosci. 25:847 (1988); C. K. Park, D. G. Nehls, D. I. Graham, G. M. Teasdale, and J. M. McCulloch, Ann. Neurol. 24:543 (1988); G. K. Steinburg, C. P. George, R. DeLaPlaz, D. K. Shibata, and T. Gross, Stroke 19:1112 (1988); J. F. Church, S. Zeman, and D. Lodge, Anesthesiology 69:702 (1988). The compounds of the present invention are useful in the treatment of neurodegenerative disorders including cerebrovascular disorders. Such disorders include but are not limited to cerebral ischemia or cerebral infarction resulting from a range of conditions such as thromboembolic or hemorrhagic stroke, cerebral vasospasm, hypoglycemia, cardiac arrest, status epilepticus, perinatal asphyxia, cerebral trauma and anoxia such as from drowning and/or pulmonary surgery. Other treatments are for schizophrenia, epilepsy, spasticity, neurodegenerative disorders such as Alzheimer's disease or Huntington's disease, Olivo-pontocerebellar atrophy, spinal cord injury, and poisoning by exogenous NMDA poisons (e.g., some forms of lathyrism). Further uses are as analgesics and anesthetics, particularly for use in surgical procedures where a finite risk of cerebrovascular damage exists. SUMMARY OF THE INVENTION The present invention concerns compounds of the formula I ##STR1## or a pharmaceutically acceptable acid addition salt thereof wherein R 1 , R 2 , R 3 , m, and n are as described herein below. The present invention also includes a pharmaceutical composition comprising a therapeutically effective amount of a compound of formula I together with a pharmaceutically acceptable carrier. The present invention also includes a method for treating cerebrovascular disorders which comprises administering to a patient in need thereof the above pharmaceutical composition in unit dosage form. The present invention also includes a method of treating disorders responsive to the blockade of glutamic and aspartic acid receptors in a patient comprising administering a therapeutically effective amount of the above composition. The invention also includes a method for treating cerebral ischemia, cerebral infarction, cerebral vasospasm, hypoglycemia, cardiac arrest, status epilepticus, cerebral trauma, schizophrenia, epilepsy, neurodegenerative disorders, Alzheimer's disease, or Huntington's disease comprising administering to a patient in need thereof a therapeutically effective amount of the above composition. The invention also includes a method for treating stroke in patients in need thereof which comprises administering to a patient in need thereof a therapeutically effective amount of the above composition. The invention also includes using as an anesthetic the above composition in surgical operations where a risk of cerebrovascular damage exists. The invention further includes processes for the preparation of compounds of formula I. The invention still further includes novel intermediates useful in the processes. DETAILED DESCRIPTION The present invention concerns compounds of the formula ##STR2## or a pharmaceutically acceptable acid addition salt thereof wherein: R 1 is hydrogen, lower alkyl, lower alkenyl, lower alkynyl, arylloweralkyl, cyclopropylloweralkyl, or a pharmaceutically acceptable labile group; R 2 and R 3 are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, halogen, amino, monoloweralkylamino, diloweralkylamino; m is an integer of from 0 to 2; and n is an integer of from 2 to 4. Preferred compounds of the instant invention are those of formula I wherein: R 1 is hydrogen, lower alkyl, lower alkenyl, cyclopropylmethyl or arylloweralkyl; R 2 and R 3 are independently hydrogen, lower alkyl, hydroxy, or lower alkoxy; m is an integer of 0 or 1; n is 2 or 3; and indicates the ring is cis relative to its attachment to the molecule. More preferred compounds of the instant invention are those of formula I wherein: R 1 is hydrogen, lower alkyl, cyclopropylmethyl, or arylloweralkyl; R 2 and R 3 are independently hydrogen, hydroxy, or lower alkoxy; m is an integer 0 or 1; and n is an integer 2 or 3. Still more preferred are compounds of formula I wherein: R 1 is hydrogen, methyl, ethyl, propyl, allyl, cyclopropylmethyl, or benzyl; R 2 and R 3 are each independently hydrogen, methoxy, or hydroxy; m is the integer 0 or 1; and n is the integer 2 or 3. Other more preferred compounds of the instant invention include: (+), (-), or (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-), or (+/-)-2,3-Dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-), or (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-), or (+/-)-2,3-Dihydro-7-methoxy-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-) or (+/-)-2,3-Dihydro-7-methoxy-1-ethyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole (+), (-), or (+/-)-2,3,4,5-tetrahydro-1-(2-propenyl)-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[g]indol-8-ol, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[g]indol-8-ol, (+), (-), or (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrol-7-ol, (+), (-), or (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrol-7-ol, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-9-methoxy-4a,10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a, 10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-9-methoxy-1-methyl-4a,10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-8-methoxy-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinolin-9-ol, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a,10b-butanobenz[h]quinolin-9-ol, (+), (-), or (+/-)-1,2,3,4-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol, and (+), (-), or (+/-)-1,2,3,4-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol. Most preferred compounds of the instant invention are: (+), (-), or (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-ethyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-propyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/--)-2,3,4,5-Tetrahydro-1-(cyclopropylmethyl)-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-phenylmethyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/--)-2,3,4,5-Tetrahydro-8-methoxy-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1-ethyl-3a,9b-butano-1H-benz[g]indole, and (+), (-), or (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1-ethyl-3a,9b-butano-1H-benz[g]indole. Compounds of the instant invention include solvates, hydrates, and pharmaceutically acceptable salts of compounds of formula I above. The compounds of the present invention contain asymmetric carbon atoms. The instant invention includes the individual enantiomers, which may be prepared or isolated by methods known in the art. Any resulting racemates can be resolved into the optical antipodes by known methods, for example by separation of the diastereomeric salts thereof, with an optically active acid, and liberating the optically active amine compound by treatment with a base. Racemic compounds of the instant invention can thus be resolved into their optical antipodes e.g., by fractional crystallization of d- or 1- (tartarates, mandelates, or camphorsulfonate) salts. The compounds of the instant invention may also be resolved into the optical antipodes by the formation of diastereomeric carbamates by reacting the compounds of the instant invention with an optically active chloroformate, for example (-)-menthyl chloroformate, or by the formation of a diastereomeric amide by reacting the compounds of the instant invention with an optically active activated carboxy acid such as that derived from (+) or (-) phenylalanine, (+) or (-) phenylglycine, (-)-camphanic acid or the like. Additional methods for resolving optical isomers, known to those skilled in the art may be used, for example those discussed by J. Jaques, A. Collet, and S. Wilen in "Enantiomers, Racemates and Resolutions", John Wiley and Sons, New York (1981). The term lower in connection with organic groups, radical or compounds includes up to and including seven members, preferably up to and including four and most preferably one, two, or three carbon atoms except as otherwise specifically described. Lower alkyl means a straight or branched chain of from one to four carbon atoms including but not limited to methyl, ethyl, propyl, isopropyl, and butyl. Lower alkenyl means a group from one to four carbon atoms, for example, but not limited to ethylene, 1,2- or 2,3-propylene, 1,2- 2,3-, or 3,4butylene. Preferred is 2,3-propylene. Lower alkynyl means a group from one to four carbon atoms, for example, but not limited to ethynyl, 2,3-propynyl, 2,3-, or 3,4-butynyl; propynyl is the preferred group. Cyclopropylloweralkyl means cyclopropyl-C 1-4 -alkyl, meaning for example, cyclopropylmethyl, 2-(cyclopropyl)ethyl, 3-(cyclopropyl)propyl; cyclopropylmethyl is the preferred group. Lower alkoxy means a group of from one to four carbon atoms, for example, but not limited to methoxy, ethoxy, propoxy; methoxy is the preferred group. Halogen is fluorine, chlorine, bromine, or iodine; fluorine, chlorine, and bromine are the preferred groups. Arylloweralkyl means aryl-C 1-4 -alkyl, meaning for example, benzyl, 2-phenylethyl, 3-phenylpropyl; preferred group is benzyl. The aryl groups may be substituted, for example, by lower alkyl, lower alkoxy, hydroxy, and halogen. Monoloweralkylamino means a group containing from one to four carbon atoms, for example, but not limited to methylamino, ethylamino, n- or i-(propylamino or butylamino). Diloweralkylamino means a group containing from one to four carbon atoms in each lower alkyl group, for example, but not limited to dimethylamino, diethylamino, di-(n-propyl)-amino, di-(n-butyl)-amino, or may represent a fused ring, for example piperidine. Physiologically labile group includes but is not limited to such derivatives described by; I. H. Pitman in Med. Chem. Rev. 2:189 (1981); J. Alexander, R. Cargill, S. R. Michelson and H. Schwam in J. Med. Chem. 31:318 (1988); V. H. Naringrekar and V. J. Stella in European Patent Application 214,009-A2 and include certain amides, such as amides of amino acids, for example glycine, or serine, enaminone derivatives and (acyloxy)alkylcarbamates. Well-known protecting groups and their introduction and removal are described, for example, in J. F. W. McOmie, Protective Groups in Organic Chemistry, Plenum Press, London, New York (1973), and T. W. Greene, Protective Groups in Organic Synthesis, Wiley, New York (1981). Salts of the compounds of the invention are preferably pharmaceutically acceptable salts. The compounds of the invention are basic amines from which acid addition salts of pharmaceutically acceptable inorganic or organic acids such as strong mineral acids, for example, hydrohalic, e.g., hydrochloric or hydrobromic acid; sulfuric, phosphoric or nitric acid; aliphatic or aromatic carboxylic or sulfonic acids, e.g., acetic, propionic, succinic, glycolic, lactic, malic, tartaric, gluconic, citric, ascorbic, maleic, fumaric, pyruvic, pamoic, nicotinic, methanesulfonic, ethanesulfonic, hydroxyethanesulfonic, benzenesulfonic, p-toluenesulfonic, or napthlenesulfonic acid can be prepared. For isolation or purification purposes, salts may be obtained which might not be useful for pharmaceutical purposes. Pharmaceutically acceptable salts useful for therapeutic purposes are preferred. The present invention also includes processes for making the compounds of formula I above. One process for the preparation of compounds of formula I is illustrated in Scheme A below. ##STR3## Step (1) The compound of formula II where m is 0 or 1 ##STR4## and R 2 and R 3 are as previously defined are treated with 1,4-dibromobutane under conditions described in Bull. Soc. Chim. France 346 (1957) to give the compounds of the formula III. ##STR5## Step (2) The compounds of the formula III are treated with lithioacetonitrile, in a solvent such as ether, tetrahydrofuran, or the like, at a temperature between -78° C. and 20° C. to afford the compounds of the formula IV. ##STR6## Step (3) The compounds of the formula IV are hydrogenated in the presence of a catalyst such as Raney Nickel, or the like, in a solvent such as methanol or ethanol containing ammonia, under a hydrogen atmosphere to give the compounds of the formula V where n is 2. ##STR7## Step (4) Alternatively, the compounds of the formula III are treated with a compound of the formula VI ##STR8## under conditions described by Evans et al in J. Amer. Chem. Soc. 371, (1979) or by other methods known to those skilled in the art, such as those described in Tetrahedron 205, (1983) to give the compounds of the formula VII. ##STR9## Step (5) The compounds of the formula VII are treated with ammonia in a solvent such as toluene, tetrahydrofuran, or the like to give the compounds of the formula VIII. ##STR10## Step (6) The compounds of the formula VIII are reduced using lithium aluminum hydride, diborane, or the like, in a solvent such as ether, tetrahydrofuran, or the like to give the compounds of the formula V wherein n is 3. Step (7) The compounds of the formula V are treated with methyl chloroformate, ethyl chloroformate, 2,2,2-trichloroethyl chloroformate or an optically active chloroformate, for example (-)-menthyl chloroformate, (-)-α-methylbenzyl chloroformate or the like, in the presence of a trialkylamine such as triethylamine, tributylamine, diisopropylethylamine or the like, in a solvent such as dichloromethane, chloroform, or the like, to give the compounds of the formula IX wherein R 5 is methyl, ethyl, 2,2,2-trichloroethyl, (-)-menthol, (-)-α-methylbenzyl, or other acid stable protecting group. ##STR11## Step (8) The compounds of the formula IX are treated with acetic acid, formic acid, triflouroacetic acid, sulfuric acid or the like or combinations thereof, preferably combinations of acetic acid and sulfuric acid to give the compounds of the formula X ##STR12## Step (9) The compounds of the formula X are treated to remove the carbamate functionalitity using methods known to those skilled in the art for example wherein R 5 is 2,2,2-trichloroethyl the compounds are treated with zinc dust in methanol, ethanol or the like, in the presence of acetic acid, to afford the compounds of the formula I wherein n is 2 or 3, m is 0 or 1, R 1 is hydrogen and R 2 and R 3 are as previously defined. Step (10) The compounds of the formula I wherein R 1 is hydrogen are treated with an aldehyde such as R formaldehyde, acetaldehyde, benzaldehyde or the like or with a ketone such as acetone, acetophenone, or the like, in the presence of a reducing agent such as sodium cyanoborohydride or the like, in a solvent such as methanol, ethanol or the like to give the compounds of the formula I wherein n is 2 or 3, m is 0 or 1, R 1 is as previously defined excepting hydrogen, and R 2 and R 3 are as previously defined. Step (11) Alternatively the compounds of the formula X are reduced in the presence of lithium aluminum hydride, diborane or the like, in a solvent such as ether, tetrahydrofuran or the like, to afford the compound of the formula I wherein R 1 is methyl. Novel intermediates useful in the preparation of compounds of formula I are: Spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one, 7'-methoxy-spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one, (+), (-), or (+/-)-3',4,-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-acetonitrile, (+), (-), or (+/-)-3',4,-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'acetonitrile, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]-2'-acetonitrile, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxy-6-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'acetonitrile, (+), (-), or (+/-)-2'-(2-aminoethyl)-3',4'-dihydrospiro[cyclopentane-1,1'(2H)-napthalen]-2'-ol, (+), (-), or (+/-)-2'-(2-aminoethyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-ol, (+), (-), or (+/-)-2'-(2-aminoethyl)-2',3'dihydrospiro[cyclopentane-1,1'-[1H]inden-2'-ol, (+), (-), or (+/-)-2'-(2-aminoethyl)-2',3'-dihydro-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden-2'-ol, Ethyl (+), (-), or (+/-)-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2,H)-naphthalen]2'-yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-naphthalen]-2'-yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-[2',3'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]2'-yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-[2',3'-dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)ethyl)carbamate, Ethyl (+), (-), or (+/-)-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[g]indole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[g]indole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3,4,5-tetrahydro-8-methoxy-3a,9b-butano-1H-benz[g]indole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3-dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3-dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate, (+), (-), or (+/-)-3',3",4',4"Tetrahydrodispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3',3",4',4"-Tetrahydro-7'-methoxydispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3",4"-Dihydrodispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3",4"-Dihydro-6'-methoxydispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3',4'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'-propanamide, (+), (-), or (+/-)-3',4'-Dihydro-2'-hydroxy-7'methoxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'propanamide, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxyspiro-[cyclopentane-1,1'-[1H]indene]-2'-propanamide, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]indene]-2'-propanamide, (+), (-), or (+/-)-2'-(3-aminopropyl)-3',4'dihydrospiro[cyclopentane-1,1'(2'H)napthalen]-2'-ol, (+), (-), or (+/-)-2'-(3-aminopropyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)napthalen]2'-ol, (+), (-), or (+/-)-2'-(3-aminopropyl)-2',3'-dihydrospiro[cyclopentane-1,1'-[1H]inden]-2'-ol , (+), (-), or (+/-)-2'-(3-aminopropyl)-2',3'-dihydro-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-ol, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)napthlene]-2'-yl)propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(2',3'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(2',3'dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)-propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4,5,6-tetrahydro-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4,5,6-tetrahydro-9-methoxy-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4-dihydro-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate, and (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4-dihydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate. The compounds of the instant invention exhibit valuable pharmacological properties by selectively blocking the N-methyl-D-aspartate sensitive excitatory amino acid receptors in mammals. The compounds are thus useful for treating diseases responsive to excitatory amino acid blockade in mammals. The effects are demonstrable in in vitro tests or in vivo animal tests using mammals or tissues or enzyme preparations thereof, e.g., mice, rats, or monkeys. The compounds are administered enterally or parenterally, for example, orally, transdermally, subcutaneously, intravenously, or intraperitoneally. Forms include but are not limited to gelatin capsules, or aqueous suspensions or solutions. The applied in vivo dosage may range between about 0.01 to 100 mg/kg, preferably between about 0.05 and 50 mg/kg, most preferably between about 0.1 and 10 mg/kg. The ability of the compounds of the instant invention to interact with phencyclidine (PCP) receptors which represents a noncompetitive NMDA antagonist binding site, is shown by Examples 23 and 27 which bind with an affinity of less than 10 μM. Tritiated 1-[1-(2-thienyl)cyclohexyl]pipiridine (TCP) binding, designated RBS1, was carried out essentially as described in J. Pharmacol. Exp. Ther. 238, 739 (1986). For medical use, the amount required of a compound of formula I or pharmacologically acceptable salt thereof--(hereinafter referred to as the active ingredient) to achieve a therapeutic effect will, of course, vary both with the particular compound, the route of administration and the mammal under treatment and the particular disorder or disease concerned. A suitable systemic dose of a compound of formula I or pharmacologically acceptable salt thereof for a mammal suffering from, or likely to suffer from any condition as described herein before is in the range 0.01 to 100 mg of base per kilogram body weight, the most preferred dosage being 0.05 to 50 mg/kg of mammal body weight. It is understood that the ordinarily skilled physician or veterinarian will readily determine and prescribe the effective amount of the compound for prophylactic or therapeutic treatment of the condition for which treatment is administered. In so proceeding, the physician or veterinarian could employ an intravenous bolus followed by intravenous infusion and repeated administrations, parenterally or orally, as considered appropriate. While it is possible for an active ingredient to be administered alone, it is preferable to present it as a formulation. Formulations of the present invention suitable for oral administration may be in the form of discrete units such as capsules, cachets, tablets, or lozenges, each containing a predetermined amount of the active ingredient; in the form of a powder or granules; in the form of a solution or a suspension in an aqueous liquid or nonaqueous liquid; or in the form of an oil-in-water emulsion or a water-in-oil emulsion. The active ingredient may also be in the form of a bolus, electuary, or paste. A tablet may be made by compressing or molding the active ingredient optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing, in a suitable machine, the active ingredient in a free-flowing form such as a powder or granules, optionally mixed with a binder, lubricant, inert diluent, surface active, or dispersing agent. Molded tablets may be made by molding, in a suitable machine, a mixture of the powdered active ingredient and a suitable carrier moistened with an inert liquid diluent. Formulations suitable for parenteral administration conveniently comprise a sterile aqueous preparation of the active ingredient which is preferable isotonic with the blood of the recipient. Formulations suitable for nasal or buccal administration (such as self-propelling powder dispensing formulations described hereinafter), may comprise 0.1 to 20% w/w, for example, 2% w/w of active ingredient. The formulations, for human medical use, of the present invention comprise an active ingredient in association with a pharmaceuticaly acceptable carrier therefor and optionally other therapeutic ingredient(s). The carrier(s) must be `acceptable` in the sense of being compatible with the other ingredients of the formulations and not deleterious to the recipient thereof. So the pharmacologically active compounds of the invention are useful in the manufacture of pharmaceutical compositions comprising an effective amount thereof in conjunction or admixture with excipients or carriers suitable for either enteral or parenteral application. Preferred are tablets and gelatin capsules comprising the active ingredient together with a) diluents, e.g. lactose, dextrose, sucrose, mannitol, sorbitol, cellulose, and/or glycine; b) lubricants, e.g. silica, talcum, stearic acid, its magnesium or calcium salt, and/or polyethyleneglycol; for tablets also c) binders e.g. magnesium aluminum silicate, starch paste, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose and/or polyvinylpyrrolidone; if desired d) disintegrants, e.g. starches, agar, alginic acid, or its sodium salt, or effervescent mixtures; and/or e) absorbents, colorants, flavors, and sweeteners. Injectable compositions are preferably aqueous isotonic solutions or suspensions, and suppositories are advantageously prepared from fatty emulsions, or suspensions. Said compositions may be sterilized and/or contain adjuvants, such as preserving, stabilizing, wetting or emulsifying agents, solution promoters, salts for regulating the osmotic pressure, and/or buffers. In addition, they may also contain other therapeutically valuable substances. Said compositions are prepared according to conventional mixing, granulating, or coating methods, respectively, and contain about 0.1 to 75%, preferably about 1 to 50%, of the active ingredient. The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods well-known in the art of pharmacy. All methods include the step of bringing the active ingredient into association with the carrier which constitutes one or more accessory ingredients. In general, the formulations are prepared by uniformly and intimately bringing the active ingredient into association with a liquid carrier or a finely divided solid carrier or both, and then, if necessary, shaping the product into the desired formulation. The following examples are illustrative of the present invention but are not intended to limit it in any way. EXAMPLE 1 ##STR13## 3',4'-Dihydrospiro[cyclopentane-1,1'(2'H)-napthlen]-2'-one A suspension of KOt-Bu (76.3 g, 0.68 mol) in 500 mL of xylene was treated dropwise with 2-tetralone (50 g, 0.34 mol). The resulting solution was treated dropwise with 1,4-dibromobutane (74.0 g, 0.34 mol) (exothermic reaction). The resulting suspension was heated to reflux for 18h. The reaction mixture was treated with water (200 mL) and the organic phase was collected. The aqueous phase was extracted with ethyl acetate (2×200 mL) and the combined organic extracts were dried (MgSO 4 ), filtered and concentrated. Distillation of the residue provided the product (65.6 g, 96%) as a colorless liquid. EXAMPLE 2 ##STR14## 3',4'-Dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthlen]-2'-one In a manner similar to that described in Example 1, 7-methoxy-2-tetralone (20.0 g, 0.113 mol) was converted to the title compound (10.3 g, 40%) as a colorless oil. EXAMPLE 3 ##STR15## Spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one In a manner similar to that described in Example 1, 2-indanone is converted to the title compound. EXAMPLE 4 ##STR16## 6'-Methoxy-spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one In a manner similar to that described in Example 1, 5-methoxy-2-indanone is converted to the title compound. EXAMPLE 5 ##STR17## (+/-)-3',4+-Dihydro-2+-hydroxyspirocyclopentane-1,1'(2'H)-napthalen]-2'-acetonitrile A solution of acetonitrile (1.1 g, 27.5 mmol) in 100 mL of anhydrous tetrahydrofuran (THF) was cooled to -78° C. and treated with lithium diisopropylamide (18 mL of a 1.5M solution in tetrahydrofuran). The resulting suspension was stirred at -78° C. for 30 minutes and treated dropwise with a solution of the product from Example 1 (5.0 g, 24.9 mmol) in 10 mL of anhydrous THF. The resulting solution was warmed to room temperature and saturated aq. NH 4 Cl solution (15 mL) was added. The organic phase was collected and the aqueous phase was extracted with ether (3×50 mL). The combined organic phases were dried (MgSO 4 ), filtered and concentrated. The solid which formed was suspended in diisopropyl ether and collected by suction filtration. The material was dried under vacuum to give the title compound (4.14 g, 69%) as a white solid mp 165°-166° C. Anal. (C 16 H 19 NO) Calc'd: C, 79.63; H, 7.94; N, 5.80. Found: C, 79.72; H, 7.86; N, 5.81. EXAMPLE 6 ##STR18## (+/-)-3',4,-Dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-acetonitrile In a manner similar to that described in Example 5, the product of Example 2 (10.0 g, 43.4 mmol) was converted to the title compound (4.33 g, 37%) as a tan solid mp 126°-127° C. Anal. (C 17 H 21 NO 2 ) Calc'd: C, 75.25; H, 7.80; N, 5.16. Found: C, 75.36; H, 7.67; N, 4.94. EXAMPLE 7 ##STR19## (+/-)-2',3'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]-2'-acetonitrile In a manner similar to that described in Example 5, the product of Example 3 is converted to the title compound. EXAMPLE 8 ##STR20## (+/-)-2',3'-Dihydro-2'-hydroxy-6-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-acetonitrile In a manner similar to that described in Example 5, the product of Example 4 is converted to the title compound. EXAMPLE 9 ##STR21## (+/-)-2'-(2-Aminoethyl)-3',4'-dihydrospiro[cyclopentane-1,1'(2'H)-napthalen]-2'-ol A solution of the product from Example 5 (2.50 g, 10.3 mmol) in 100 mL of methanolic ammonia was hydrogenated over Raney nickel (2.0 g) at 52 psi for 7.5 hours. The reaction mixture was filtered to remove the catalyst and the filtrate concentrated to give the title compound (2.59 g, quantitative) as a pale green solid mp 107°-109° C. Anal (C 16 H 23 NO) Calc'd: C, 79.63; H, 7.94; N, 5.81. Found: C, 79.37; H, 8.02; N, 5.59. EXAMPLE 10 ##STR22## (+/-)-2'-(2-Aminoethyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-ol In a manner similar to that described for Example 9, the product of Example 6 (4.85 g, 17.9 mmol) was hydrogenated to give the title compound (4.86 g, 99%) as a pale green solid. Anal. (C 17 H 25 NO 2 ) Calc'd: C, 74.14; H, 9.15; N, 5.08. Found: C, 73.40; H, 9.19; N, 5.04. EXAMPLE 11 ##STR23## (+/-)-2'-(2-Aminoethyl)-2',3'-dihydrospiro[cyclopentane-1,1'-[1H]inden-2'-ol In a manner similar to that described for Example 9, the product of Example 7 is hydrogenated to give the title compound. EXAMPLE 12 ##STR24## (+/-)-2'-(2-Aminoethyl)-2',3'-dihydro-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden-2'-ol In a manner similar to that described for Example 9, the product of Example 8 is hydrogenated to give the title compound. EXAMPLE 13 ##STR25## Ethyl (+/-)-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-yl)ethyl]carbamate A solution of the product from Example 9 (1.05 g, 4.28 mmol) and triethylamine (0.44 g, 4.35 mmol) in 10 mL of CH 2 Cl 2 was cooled to 0° C. and ethyl chloroformate (0.47 g, 4.33 mmol) in 5 mL CH 2 Cl 2 was added dropwise. The reaction was warmed to room temperature and washed with water. The aqueous phase was extracted with CH 2 Cl 2 (3×20 mL) and the combined organic extracts were dried (MgSO 4 ), filtered and concentrated. The residue was purified by chromatography (silica gel, 1:1 heptane/ethyl acetate) to give the title compound (1.33 g, 98%) as an oil. EXAMPLE 14 ##STR26## 2,2,2-Trichloroethyl (+/-)-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-naphthalen]-2'-yl)ethyl]carbamate A solution of the product from Example 9 (0.88 g, 3.59 mmol) and triethylamine (0.40 g, 3.78 mmol) in 10 mL of CH 2 Cl 2 was cooled to 0° C. and treated dropwise with 2,2,2-trichloroethylchloroformate (0.80 g, 3.78 mmol) in 2 mL CH 2 Cl 2 . The resulting solution was stirred at 0° C. for 30 minutes and warmed to room temperature. The reaction mixture was washed with saturated aq. NaHCO 3 solution (10 mL). The aqueous phase was extracted with CH 2 Cl 2 (10 mL). The combined organic extracts were dried (MgSO 4 ), filtered and concentrated. The residue was purified by chromatography (silica gel, 10:1 heptane/ethyl acetate) to give the title compound (1.18 g, 78%) as a viscous oil. EXAMPLE 15 ##STR27## 2,2,2-Trichloroethyl (+/-)-[2-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-naphthalen]-2'-2'-yl)ethyl]carbamate In a manner similar to that described in Example 14, the product of Example 10 (4.66 g, 16.9 mmol) is converted to the title compound (6.81 g, 89%) as a foamy white solid. EXAMPLE 16 ##STR28## 2,2,2-Trichloroethyl (+/-)-[2-[2',3'-dihydro-2'-hydroxy-spiro[cyclopentane-1,1'-[1H]inden]-2'-yl)ethyl]carbamate In a manner similar to that described in Example 14, the product of Example 11 is converted to the title compound. EXAMPLE 17 ##STR29## 2,2,2-Trichloroethyl (+/-)-2-[2',3'-dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)ethyl]carbamate In a manner similar to that described in Example 14, the product of Example 12 is converted to the title compound. EXAMPLE 18 ##STR30## Ethyl (+/-)-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[q]indole-1-carboxylate A solution of the product from Example 13 (1.68 g, 5.29 mmol) in 15 mL of 3:1 acetic acid/concentrated sulfuric acid (v/v) was stirred at room temperature for 18 hours. The reaction mixture was poured into water (50 mL) and the resulting mixture was extracted with CH 2 Cl 2 (4×30 mL). The combined organic extracts were dried (MgSO 4 ), filtered and concentrated. The residue was dissolved in CH 2 Cl 2 (100 mL) and washed with saturated aq. bicarbonate solution (30 mL). The organic phase was dried (MgSPO 4 ), filtered and concentrated. The residue was purified by chromatography (silica gel, 9:1 heptane/ethyl acetate) to give the title compound (0.94 g, 59%) as a white solid mp 67°-69° C. Anal. (C 19 H 25 NO 2 ) Calc'd: C, 76.22; H, 8.42; N, 4.68. Found: C, 75.99; H, 8.38; N, 4.41. EXAMPLE 19 ##STR31## 0 2,2,2-Trichloroethyl (+/-)-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[q]indole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 14 (0.98 g, 2.33 mmol) was converted to the title compound (0.71 g, 76%) as an oil. EXAMPLE 20 ##STR32## 2,2,2-Trichloroethyl (+/-)-2,3,4,5-tetrahydro-8-methoxy-3a,9b-butano-1H-benz[q]indole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 15 (5.16 g, 11.4 mmol) was converted to the title compound (4.18 g, 84%) as an oil. EXAMPLE 21 ##STR33## 2,2,2-Trichloroethyl (+/-)-2,3-dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 16 is converted to the title compound. EXAMPLE 22 ##STR34## 2,2,2-Trichloroethyl (+/-)-2,3-dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 17 is converted to the title compound. EXAMPLE 23 ##STR35## (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[q]indole hydrochloride A solution of the product from Example 19 (0.70 g, 1.74 mmol) in 20 mL of methanol and 0.5 mL acetic acid was treated with zinc dust (1.58 g, 320 mesh) and the resulting suspension stirred at room temperature for three hours. The reaction mixture was filtered and the filtrate concentrated. The residue was dissolved in ether (30 mL) and extracted with aqueous 1N HCl (3×15 mL). The combined acid extracts are made basic (pH=11) with potassium carbonate and the resulting aqueous solution was extracted with CH 2 Cl 2 (5×15 mL). The combined organic extracts were dried (Na 2 SO 4 ), filtered and concentrated. The residue (0.30 g) was converted to its HCl salt by dissolution in ether and treatment with a saturated solution of HCl (gas) in ether. The solid which formed was collected by filtration and dried under vacuum (100° C.) to give the title compound (0.25 g, 54%) as a white solid mp >270° C. Anal (C 16 H 19 N.HCl) Calc'd: C, 72.85; H, 8.40; N, 5.31; Cl, 13.44. Found: C, 72.66; H, 8.38, N, 4.98; Cl, 13.83. EXAMPLE 24 ##STR36## (+/-)-2,3,4,5-Tetrahydro-8-methoxy-3a,9b-butano-1H-benz]q]indole In a manner similar to that described in Example 23, the product of Example 20 (3.76 g, 8.67 mmol) was converted to the title compound 1.47 g, 70%) as an oil. An analytical sample was prepared by crystallization of the fumarate salt from acetone which gave a white solid mp 203°-204° C. Anal. (C 17 H 23 NO.C 4 H 4 O 4 ) Calc'd: C, 67.54; H, 7.29; N, 3.75. Found: C, 67.55; H, 7.18; N, 3.61. EXAMPLE 25 ##STR37## (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole In a manner similar to that described in Example 23, the product of Example 21 is converted to the title compound. EXAMPLE 26 ##STR38## (+/-)-2,3-Dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole In a manner similar to that described in Example 23, the product of Example 22 is converted to the title compound. EXAMPLE 27 ##STR39## (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[q]indole hydrochloride A solution of the product from Example 18 (0.77 g, 2.56 mmol) in 5 mL of THF was added dropwise to a suspension of lithium aluminum hydride (0.76 g, 20.0 mmol) in 15 mL of THF. The reaction mixture was stirred at room temperature for 18 hours and then heated to reflux for 1 hour. The reaction mixture was cooled to room temperature and quenched by the addition of small portions of Na 2 SO 4 -10H 2 O until no further gas evolution was observed. The reaction mixture was filtered and the filtrate was concentrated. The residue was dissolved in ether and treated with a saturated solution of dry HCl in ether. The solid which formed was collected by suction filtration and dried under vacuum (100° C.) to give the product (0.51 g, 72%) as a white solid mp 241°-253° C. Anal. (C 17 H 23 N.HCl) Calc'd: C, 73.49; H, 8.71; N, 5.04; Cl, 12.76 . Found: C, 73.39; H, 8.73; N, 4.82; Cl, 13.16. EXAMPLE 28 ##STR40## (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1methyl-3a,9b-butano-1H-benz[q]indole A solution of the product from Example 24 (0.79 g, 3.08 mmol) and sodium cyanoborohydride (0.80 g, 12.7 mmol) in 10 mL methanol was treated dropwise with a 37% aqueous formalin solution (5 mL). The resulting solution was stirred at room temperature for 30 minutes, concentrated, and partitioned between 1N HCl (20 mL) and ether (20 mL). The organic phase was extracted with 1N HCl (2×10 mL) and the combined aqueous extracts were washed with ether. The aqueous phase was made basic with K 2 CO 3 and extracted with CH 2 Cl 2 (3×20 mL). The combined organic extracts were dried K 2 CO 3 , filtered and concentrated to give the title compound (0.87 g, quantitative) as a white solid mp 100°-102° C. Anal. (C 18 H 25 NO) Calc'd: C, 79.66; H, 9.29; N, 5.16. Found: C, 79.52; H, 9.53; N, 4.71. EXAMPLE 29 ##STR41## (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole In a manner similar to that described in Example 28, the product of Example 25 is converted to the title compound. EXAMPLE 30 ##STR42## (+/-)-2,3-Dihydro-7-methoxy-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b)pyrrole In a manner similar to that described in Example 28, the product of Example 26 is converted to the title compound. EXAMPLE 31 ##STR43## (+/-)-2,3,4,5-Tetrahydro-1-ethyl-3a,9b-butano-1-benz[q]indole fumarate In a manner similar to that described in Example 28, the product from Example 23 (0.30 g, 1.32 mmol) and sodium cyanoborohydride (0.30 g, 4.77 mmol) was treated dropwise with acetaldehyde (0.20 g, 4.10 mmol) in 5 mL of methanol. Workup followed by crystallization of the fumarate salt from acetone gave the title compound (0.32 g, 65%) as a white solid mp 172°-173° C. Anal. (C 18 H 25 N.C 4 H 4 O 4 ) Calc'd: C, 71.13; H, 7.87; N, 3.77. Found: C, 70.90: H, 7.79; N, 3.75. EXAMPLE 32 ##STR44## (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1-ethyl-3a,9b-butano-1H-benz[q]indole hydrobromide In a manner similar to that described in Example 31, the product of Example 24 (0.27 g, 1.13 mmol) and acetaldehyde (0.32 g, 7.12 mmol) are reacted. Workup, followed by crystallization from ether and HBr gave the title compound (0.27 g, 64%) as a white solid mp 248°-251° C. Anal. (C 19 H 27 NO.HBr) Calc'd: C, 62.29; H, 7.71; N, 3.82; Br, 21.81. Found: C, 62.39; H, 7.65; N, 3.77; Br, 21.98. EXAMPLE 33 ##STR45## (+/-)-2,3,4,5-Tetrahydro-1-propyl-3a,9b-butano-1H-benz[q]indole hydrobromide In a manner similar to that described in Example 32, the product from Example 23 (0.25 g, 1.10 mmol) and propionaldehyde (0.20 g, 3.47 mmol) was converted to the title compound (0.23 g, 60%) as a white solid mp 196°-198° C. Anal. (C 19 H 27 N.HBr) Calc'd: C, 64.92; H, 8.13; N, 4.07; Br, 23.09. Found: C, 65.14; H, 8.06; N, 4.00; Br, 22.80. EXAMPLE 34 ##STR46## (+/-)-2,3,4,5-tetrahydro-1-(cyclopropylmethyl)-3a,9b -butano-1H-benz[q]indole fumarate In a manner similar to that described in Example 31, the product from Example 23 (0.25 g, 1.10 mmol) and cyclopropanecarboxaldehyde (0.23 g, 1.10 mmol) was converted to the title compound (0.26 g, 58%) as a white solid mp 150°-152° C. Anal. (C 20 H 27 N.1.2C 4 H 4 O 4 ) Calc'd: C, 70.80; H, 7.62; N, 3.33. Found: C, 71.05; H, 7.67, N, 3.32. EXAMPLE 35 ##STR47## (+/-)-2,3,4,5-tetrahydro-1-phenylmethyl-3a,9b-butano-1H-benz[q]indole hydrochloride In a manner similar to that described in Example 32, the product from Example 23 (0.34 g, 1.50 mmol) and benzaldehyde are reacted. Workup, followed crystallization from ether and HCl gave the title compound (0.22 g, 42%) as a white solid mp 235°-237° C. Anal. (C 23 H 27 N.HCl) Calc'd C, 78.05; H, 7.98; N, 3.96; Cl, 10.02. Found: C, 77.60; H, 8.00, N, 3.34; Cl, 10.24. EXAMPLE 36 ##STR48## (+/-)-2,3,4,5-Tetrahydro-1-(2-propenyl)-3a,9b-butano-1H-benz[q]indole In a manner similar to that described in Example 32, the product from Example 23 is converted to the title compound. EXAMPLE 37 ##STR49## (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[q]indol-8-ol A solution of the product from Example 24 is heated to reflux in 48% aqueous HBr until the starting material is consumed. The reaction mixture is poured into cold NH 4 OH solution and extracted into ethyl acetate. The combined organic extracts are dried (Na 2 SO 4 ) and concentrated to give the title compound. EXAMPLE 38 ##STR50## (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[q]indol-8-ol In a manner similar to that described in Example 37, the product from Example 28 is converted to the title compound. EXAMPLE 39 ##STR51## (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrol-7-ol In a manner similar to that described in Example 37, the product from Example 26 is converted to the title compound. EXAMPLE 40 ##STR52## (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]-pyrrol-7-ol In a manner similar to that described in Example 37, the product from Example 30 is converted to the title compound. EXAMPLE 41 ##STR53## 3',3",4',4"-Tetrahydrodispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)-furan]-5"-one A solution of triethylsilyl N,N,N',N'-tetramethyl phosphoramidate (J. Amer. Chem. Soc. 1978, 100, 3468) (1.1 eq.) in anhydrous ether is cooled to 0° C. and treated with acrolein (1.0 eq.) in anhydrous ether. The resulting solution is stirred at 0° C. for 4.5 hours then cooled to -78° C. and a solution of n-butyllithium (1.0 eq.) is added. The resulting solution is treated with the product from Example 1 (1.0 eq.) and stirred at -78° C. for several hours. The reaction mixture is quenched with brine and extracted with several portions of ether. The combined extracts are dried and concentrated. The residue is dissolved in THF and cooled to 0° C. and tetra-n-butylammonium flouride (5 eq.) is added. The reaction mixture is warmed to room temperature and worked up as above to give the title compound. EXAMPLE 42 ##STR54## 3',3",4',4"-Tetrahydro-7'-methoxydispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)furan]-5"-one In a manner similar to that described in Example 41, the product from Example 2 is converted to the title compound. EXAMPLE 43 ##STR55## 3",4"-Dihydrodispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one In a manner similar to that described in Example 41, the product from Example 3 is converted to the title compound. EXAMPLE 44 ##STR56## 3",4"-Dihydro-6'-methoxydispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one In a manner similar to that described in Example 41, the product from Example 4 is converted to the title compound. EXAMPLE 45 ##STR57## (+/-)-3',4'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'-propanamide A solution of the product from Example 41 is placed in a high pressure reactor and dissolved in tetrahydrofuran. Ammonia is condensed into the solution and the reaction vessel is sealed and the reaction mixture is stirred at room temperature for approximately 24 hours. The reaction vessel is vented and the remaining solvent is concentrated to give the title compound. EXAMPLE 46 ##STR58## (+/-)-3',4'-Dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'-propanamide In a manner similar to that described in Example 45, the product from Example 42 is converted to the title compound. EXAMPLE 47 ##STR59## (+/-)-2',3'-Dihydro-2,-hydroxyspiro[cyclopentane-1,1'-[1H]indene]-2,-propanamide In a manner similar to that described in Example 45, the product from Example 43 is converted to the title compound. EXAMPLE 48 ##STR60## (+/-)-2',3'-Dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]indene]-2'-propanamide In a manner similar to that described in Example 45, the product from Example 44 is converted to the title compound. EXAMPLE 49 ##STR61## (+/-)-2'-(3-Aminopropyl)-3',4'-dihydrospiro[cyclopentane-1,1'(2'H)napthalen]-2'-ol A solution of the product from Example 45, in tetrahydrofuran (THF) is added dropwise to a suspension of lithium aluminumhydride in THF. The resulting suspension is heated to reflux for 1 hour and then stirred at room temperature for 18 hours. The reaction mixture is quenched by the addition of small portions of Na 2 SO 4 -10H 2 O until no more gas evolution is observed. The resulting suspension is filtered and the filtrate is concentrated to give the title compound. EXAMPLE 50 ##STR62## (+/-)-2'-(3-Aminopropyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)napthalen]-2'-ol In a manner similar to that described in Example 49, the product from Example 46 is converted to the title compound. EXAMPLE 51 ##STR63## (+/-)-2'-(3-Aminopropyl)-2',3'-dihydrospiro[cyclopentane-1,1'-[1H]inden]-2'-ol In a manner similar to that described in Example 49, the product from Example 47 is converted to the title compound. EXAMPLE 52 ##STR64## (+/-)-2'-(3-Aminopropyl)-2',3'-dihydro-6'-methoxyspiro[[cyclopentane-1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate In a manner similar to that described in Example 49, the product from Example 48 is converted to the title compound. EXAMPLE 53 ##STR65## 2,2,2-Trichloroethyl (+/-)-3-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate A solution of the product from Example 49 (1.0 eq.) and triethylamine (1.1 eq.) in CH 2 Cl 2 is cooled to 0° C. and a solution of 2,2,2-trichloroethylchloroformate (1.1 eq.) in CH 2 Cl 2 is added dropwise. The resulting solution is stirred at 0° C. for 30 minutes and warmed to room temperature. The reaction mixture is washed with bicarbonate, dried and concentrated to give the title compound. EXAMPLE 54 ##STR66## 2,2,2-Trichloroethyl (+/-)-[3-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate In a manner similar to that described in Example 53, the product from Example 50 is converted to the title compound. EXAMPLE 55 ##STR67## 2,2,2-Trichloroethyl (+/-)-[3-(2',3'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'[1H]inden]-2'-yl)propyl]carbamate In a manner similar to that described in Example 53, the product from Example 51 is converted to the title compound. EXAMPLE 56 ##STR68## 2,2,2-Trichloroethyl (+/-)-[3-(2',3'-dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'[1H]inden]-2'-yl)propyl]carbamate In a manner similar to that described in Example 53, the product from Example 52 is converted to the title compound. EXAMPLE 57 ##STR69## 2,2,2-Trichloroethyl (+/-)-3,4,5,6-tetrahydro-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 53 is converted to the title compound. EXAMPLE 58 ##STR70## 2,2,2-Trichloroethyl (+/-)-3,4,5,6-tetrahydro-9-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 54 is converted to the title compound. EXAMPLE 59 ##STR71## 2,2,2-Trichloroethyl (+/-)-3,4-dihydro-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 55 is converted to the title compound. EXAMPLE 60 ##STR72## 2,2,2-Trichloroethyl (+/-)-3,4-dihydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 56 is converted to the title compound. EXAMPLE 61 ##STR73## (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinoline In a manner similar to that described in Example 23, the product from Example 57 is converted to the title compound. EXAMPLE 62 ##STR74## (+/-)-1,2,3,4,5,6-Hexahydro-9-methoxy-4a,10b-butanobenz[h]-quinoline In a manner similar to that described in Example 23, the product from Example 58 is converted to the title compound. EXAMPLE 63 ##STR75## (+/-)-1,2,3,4-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 23, the product from Example 59 is converted to the title compound. EXAMPLE 64 ##STR76## (+/-)-1,2,3,4-Tetrahydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 23, the product from Example 60 is converted to the title compound. EXAMPLE 65 ##STR77## (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a,10b-butanobenz[h]quinoline In a manner similar to that described in Example 28, the product from Example 61 is converted to the title compound. EXAMPLE 66 ##STR78## (+/--)-1,2,3,4,5,6-Hexahydro-9-methoxy-1-methyl-4a,10b-butanobenz[h]quinoline In a manner similar to that described in Example 28, the product from Example 62 is converted to the title compound. EXAMPLE 67 ##STR79## (+/-)-1,2,3,4-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 28, the product from Example 63 is converted to the title compound. EXAMPLE 68 ##STR80## (+/-)-1,2,3,4-Tetrahydro-8-methoxy-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 28, the product from Example 64 is converted to the title compound. EXAMPLE 69 ##STR81## (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinoline-9-ol In a manner similar to that described in Example 37, the product from Example 62 is converted to the title compound. EXAMPLE 70 ##STR82## (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a,10b-butanobenz[h]quinoline-9-ol In a manner similar to that described in Example 37, the product from Example 64 is converted to the title compound. EXAMPLE 71 ##STR83## (+/-)-1,2,3,4-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol In a manner similar to that described in Example 37, the product from Example 66 is converted to the title compound. EXAMPLE 72 ##STR84## (+/-)-1,2,3,4-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol In a manner similar to that described in Example 37, the product from Example 68 is converted to the title compound.
Processes for the preparation of a series of tetracyclic amines useful in the treatment and/or prevention of cerebrovascular disorders are disclosed.
Identify and summarize the most critical features from the given passage.
[ "This is a divisional application of U.S. Ser.", "No. 07/677,029 filed Mar. 28, 1991, now U.S. Pat. No. 5,070,093, which is a divisional application of U.S. Ser.", "No. 07/565,306 filed Aug. 9, 1990, now U.S. Pat. No. 5,109,136.", "BACKGROUND OF THE INVENTION Excessive excitation by neurotransmitters can cause the degeneration and death of neurons.", "It is believed that this degeneration is in part mediated by the excitotoxic actions of glutamate and aspartate at the N-methyl-D-aspartate (NMDA) receptor.", "This excitotoxic action is responsible for the loss of neurons in cerebrovascular disorders such as: cerebral ischemia or cerebral infraction resulting from a range of conditions such as thromboembolic or hemorrhagic stroke, cerebral vasospasm, hypoglycemia, cardiac arrest, status epilepticus, perinatal asphyxia, cerebral trauma and anoxia (such as from drowning and pulmonary surgery).", "There are no specific therapies for these neurodegenerative diseases, however, compounds which act specifically as antagonists of the NMDA receptor complex, either competitively or noncompetitively, offer a novel therapeutic approach to these disorders: R. Schwarcz and B. Meldrum, The Lancet 140 (1985);", "B. Meldrum in "Neurotoxins and Their Pharmacological Implications"", "edited by P. Jenner, Raven Press, New York (1987);", "D. W. Choi, Neuron 1:623 (1988).", "Confirmation of the protective effects of noncompetitve NMDA antagonists in various pharmacological models of neurodegenerative disorders have appeared in the literature: J. W. McDonald, F. S. Silverstein, and M. V. Johnston, Eur.", "J. Pharmocol.", "140:359 (1987);", "R. Gill, A. C. Foster, and G. N. Woodruff, J. Neurosci.", "7:3343 (1987);", "S. M. Rothman, J. H. Thurston, R. E. Hauhart, G. D. Clark, and J. S. Soloman, Neurosci.", "21:673 (1987);", "M. P. Goldbert, P-C.", "Pham, and D. W. Choi, Neurosci.", "Lett.", "80:11 (1987);", "L. F. Copeland, P. A. Boxer, and F. W. Marcoux, Soc.", "Neurosci.", "Abstr.", "14 (part 1):420 (1988);", "J. A. Kemp, A. C. Foster, R. Gill, and G. N. Woodruff, TIPS 8:414 (1987);", "R. Gill, A. C. Foster, and G. N. Woodruff, J. Neurosci.", "25:847 (1988);", "C. K. Park, D. G. Nehls, D. I. Graham, G. M. Teasdale, and J. M. McCulloch, Ann.", "Neurol.", "24:543 (1988);", "G. K. Steinburg, C. P. George, R. DeLaPlaz, D. K. Shibata, and T. Gross, Stroke 19:1112 (1988);", "J. F. Church, S. Zeman, and D. Lodge, Anesthesiology 69:702 (1988).", "The compounds of the present invention are useful in the treatment of neurodegenerative disorders including cerebrovascular disorders.", "Such disorders include but are not limited to cerebral ischemia or cerebral infarction resulting from a range of conditions such as thromboembolic or hemorrhagic stroke, cerebral vasospasm, hypoglycemia, cardiac arrest, status epilepticus, perinatal asphyxia, cerebral trauma and anoxia such as from drowning and/or pulmonary surgery.", "Other treatments are for schizophrenia, epilepsy, spasticity, neurodegenerative disorders such as Alzheimer's disease or Huntington's disease, Olivo-pontocerebellar atrophy, spinal cord injury, and poisoning by exogenous NMDA poisons (e.g., some forms of lathyrism).", "Further uses are as analgesics and anesthetics, particularly for use in surgical procedures where a finite risk of cerebrovascular damage exists.", "SUMMARY OF THE INVENTION The present invention concerns compounds of the formula I ##STR1## or a pharmaceutically acceptable acid addition salt thereof wherein R 1 , R 2 , R 3 , m, and n are as described herein below.", "The present invention also includes a pharmaceutical composition comprising a therapeutically effective amount of a compound of formula I together with a pharmaceutically acceptable carrier.", "The present invention also includes a method for treating cerebrovascular disorders which comprises administering to a patient in need thereof the above pharmaceutical composition in unit dosage form.", "The present invention also includes a method of treating disorders responsive to the blockade of glutamic and aspartic acid receptors in a patient comprising administering a therapeutically effective amount of the above composition.", "The invention also includes a method for treating cerebral ischemia, cerebral infarction, cerebral vasospasm, hypoglycemia, cardiac arrest, status epilepticus, cerebral trauma, schizophrenia, epilepsy, neurodegenerative disorders, Alzheimer's disease, or Huntington's disease comprising administering to a patient in need thereof a therapeutically effective amount of the above composition.", "The invention also includes a method for treating stroke in patients in need thereof which comprises administering to a patient in need thereof a therapeutically effective amount of the above composition.", "The invention also includes using as an anesthetic the above composition in surgical operations where a risk of cerebrovascular damage exists.", "The invention further includes processes for the preparation of compounds of formula I. The invention still further includes novel intermediates useful in the processes.", "DETAILED DESCRIPTION The present invention concerns compounds of the formula ##STR2## or a pharmaceutically acceptable acid addition salt thereof wherein: R 1 is hydrogen, lower alkyl, lower alkenyl, lower alkynyl, arylloweralkyl, cyclopropylloweralkyl, or a pharmaceutically acceptable labile group;", "R 2 and R 3 are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, halogen, amino, monoloweralkylamino, diloweralkylamino;", "m is an integer of from 0 to 2;", "and n is an integer of from 2 to 4.", "Preferred compounds of the instant invention are those of formula I wherein: R 1 is hydrogen, lower alkyl, lower alkenyl, cyclopropylmethyl or arylloweralkyl;", "R 2 and R 3 are independently hydrogen, lower alkyl, hydroxy, or lower alkoxy;", "m is an integer of 0 or 1;", "n is 2 or 3;", "and indicates the ring is cis relative to its attachment to the molecule.", "More preferred compounds of the instant invention are those of formula I wherein: R 1 is hydrogen, lower alkyl, cyclopropylmethyl, or arylloweralkyl;", "R 2 and R 3 are independently hydrogen, hydroxy, or lower alkoxy;", "m is an integer 0 or 1;", "and n is an integer 2 or 3.", "Still more preferred are compounds of formula I wherein: R 1 is hydrogen, methyl, ethyl, propyl, allyl, cyclopropylmethyl, or benzyl;", "R 2 and R 3 are each independently hydrogen, methoxy, or hydroxy;", "m is the integer 0 or 1;", "and n is the integer 2 or 3.", "Other more preferred compounds of the instant invention include: (+), (-), or (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-), or (+/-)-2,3-Dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-), or (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-), or (+/-)-2,3-Dihydro-7-methoxy-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole, (+), (-) or (+/-)-2,3-Dihydro-7-methoxy-1-ethyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole (+), (-), or (+/-)-2,3,4,5-tetrahydro-1-(2-propenyl)-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[g]indol-8-ol, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[g]indol-8-ol, (+), (-), or (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrol-7-ol, (+), (-), or (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrol-7-ol, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-9-methoxy-4a,10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a, 10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-9-methoxy-1-methyl-4a,10b-butanobenz[h]quinoline, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,-Tetrahydro-8-methoxy-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinolin-9-ol, (+), (-), or (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a,10b-butanobenz[h]quinolin-9-ol, (+), (-), or (+/-)-1,2,3,4-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol, and (+), (-), or (+/-)-1,2,3,4-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol.", "Most preferred compounds of the instant invention are: (+), (-), or (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-ethyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-propyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/--)-2,3,4,5-Tetrahydro-1-(cyclopropylmethyl)-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-1-phenylmethyl-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/--)-2,3,4,5-Tetrahydro-8-methoxy-3a,9b-butano-1H-benz[g]indole, (+), (-), or (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1-ethyl-3a,9b-butano-1H-benz[g]indole, and (+), (-), or (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1-ethyl-3a,9b-butano-1H-benz[g]indole.", "Compounds of the instant invention include solvates, hydrates, and pharmaceutically acceptable salts of compounds of formula I above.", "The compounds of the present invention contain asymmetric carbon atoms.", "The instant invention includes the individual enantiomers, which may be prepared or isolated by methods known in the art.", "Any resulting racemates can be resolved into the optical antipodes by known methods, for example by separation of the diastereomeric salts thereof, with an optically active acid, and liberating the optically active amine compound by treatment with a base.", "Racemic compounds of the instant invention can thus be resolved into their optical antipodes e.g., by fractional crystallization of d- or 1- (tartarates, mandelates, or camphorsulfonate) salts.", "The compounds of the instant invention may also be resolved into the optical antipodes by the formation of diastereomeric carbamates by reacting the compounds of the instant invention with an optically active chloroformate, for example (-)-menthyl chloroformate, or by the formation of a diastereomeric amide by reacting the compounds of the instant invention with an optically active activated carboxy acid such as that derived from (+) or (-) phenylalanine, (+) or (-) phenylglycine, (-)-camphanic acid or the like.", "Additional methods for resolving optical isomers, known to those skilled in the art may be used, for example those discussed by J. Jaques, A. Collet, and S. Wilen in "Enantiomers, Racemates and Resolutions", John Wiley and Sons, New York (1981).", "The term lower in connection with organic groups, radical or compounds includes up to and including seven members, preferably up to and including four and most preferably one, two, or three carbon atoms except as otherwise specifically described.", "Lower alkyl means a straight or branched chain of from one to four carbon atoms including but not limited to methyl, ethyl, propyl, isopropyl, and butyl.", "Lower alkenyl means a group from one to four carbon atoms, for example, but not limited to ethylene, 1,2- or 2,3-propylene, 1,2- 2,3-, or 3,4butylene.", "Preferred is 2,3-propylene.", "Lower alkynyl means a group from one to four carbon atoms, for example, but not limited to ethynyl, 2,3-propynyl, 2,3-, or 3,4-butynyl;", "propynyl is the preferred group.", "Cyclopropylloweralkyl means cyclopropyl-C 1-4 -alkyl, meaning for example, cyclopropylmethyl, 2-(cyclopropyl)ethyl, 3-(cyclopropyl)propyl;", "cyclopropylmethyl is the preferred group.", "Lower alkoxy means a group of from one to four carbon atoms, for example, but not limited to methoxy, ethoxy, propoxy;", "methoxy is the preferred group.", "Halogen is fluorine, chlorine, bromine, or iodine;", "fluorine, chlorine, and bromine are the preferred groups.", "Arylloweralkyl means aryl-C 1-4 -alkyl, meaning for example, benzyl, 2-phenylethyl, 3-phenylpropyl;", "preferred group is benzyl.", "The aryl groups may be substituted, for example, by lower alkyl, lower alkoxy, hydroxy, and halogen.", "Monoloweralkylamino means a group containing from one to four carbon atoms, for example, but not limited to methylamino, ethylamino, n- or i-(propylamino or butylamino).", "Diloweralkylamino means a group containing from one to four carbon atoms in each lower alkyl group, for example, but not limited to dimethylamino, diethylamino, di-(n-propyl)-amino, di-(n-butyl)-amino, or may represent a fused ring, for example piperidine.", "Physiologically labile group includes but is not limited to such derivatives described by;", "I. H. Pitman in Med.", "Chem.", "Rev. 2:189 (1981);", "J. Alexander, R. Cargill, S. R. Michelson and H. Schwam in J. Med.", "Chem.", "31:318 (1988);", "V. H. Naringrekar and V. J. Stella in European Patent Application 214,009-A2 and include certain amides, such as amides of amino acids, for example glycine, or serine, enaminone derivatives and (acyloxy)alkylcarbamates.", "Well-known protecting groups and their introduction and removal are described, for example, in J. F. W. McOmie, Protective Groups in Organic Chemistry, Plenum Press, London, New York (1973), and T. W. Greene, Protective Groups in Organic Synthesis, Wiley, New York (1981).", "Salts of the compounds of the invention are preferably pharmaceutically acceptable salts.", "The compounds of the invention are basic amines from which acid addition salts of pharmaceutically acceptable inorganic or organic acids such as strong mineral acids, for example, hydrohalic, e.g., hydrochloric or hydrobromic acid;", "sulfuric, phosphoric or nitric acid;", "aliphatic or aromatic carboxylic or sulfonic acids, e.g., acetic, propionic, succinic, glycolic, lactic, malic, tartaric, gluconic, citric, ascorbic, maleic, fumaric, pyruvic, pamoic, nicotinic, methanesulfonic, ethanesulfonic, hydroxyethanesulfonic, benzenesulfonic, p-toluenesulfonic, or napthlenesulfonic acid can be prepared.", "For isolation or purification purposes, salts may be obtained which might not be useful for pharmaceutical purposes.", "Pharmaceutically acceptable salts useful for therapeutic purposes are preferred.", "The present invention also includes processes for making the compounds of formula I above.", "One process for the preparation of compounds of formula I is illustrated in Scheme A below.", "##STR3## Step (1) The compound of formula II where m is 0 or 1 ##STR4## and R 2 and R 3 are as previously defined are treated with 1,4-dibromobutane under conditions described in Bull.", "Soc.", "Chim.", "France 346 (1957) to give the compounds of the formula III.", "##STR5## Step (2) The compounds of the formula III are treated with lithioacetonitrile, in a solvent such as ether, tetrahydrofuran, or the like, at a temperature between -78° C. and 20° C. to afford the compounds of the formula IV.", "##STR6## Step (3) The compounds of the formula IV are hydrogenated in the presence of a catalyst such as Raney Nickel, or the like, in a solvent such as methanol or ethanol containing ammonia, under a hydrogen atmosphere to give the compounds of the formula V where n is 2.", "##STR7## Step (4) Alternatively, the compounds of the formula III are treated with a compound of the formula VI ##STR8## under conditions described by Evans et al in J. Amer.", "Chem.", "Soc.", "371, (1979) or by other methods known to those skilled in the art, such as those described in Tetrahedron 205, (1983) to give the compounds of the formula VII.", "##STR9## Step (5) The compounds of the formula VII are treated with ammonia in a solvent such as toluene, tetrahydrofuran, or the like to give the compounds of the formula VIII.", "##STR10## Step (6) The compounds of the formula VIII are reduced using lithium aluminum hydride, diborane, or the like, in a solvent such as ether, tetrahydrofuran, or the like to give the compounds of the formula V wherein n is 3.", "Step (7) The compounds of the formula V are treated with methyl chloroformate, ethyl chloroformate, 2,2,2-trichloroethyl chloroformate or an optically active chloroformate, for example (-)-menthyl chloroformate, (-)-α-methylbenzyl chloroformate or the like, in the presence of a trialkylamine such as triethylamine, tributylamine, diisopropylethylamine or the like, in a solvent such as dichloromethane, chloroform, or the like, to give the compounds of the formula IX wherein R 5 is methyl, ethyl, 2,2,2-trichloroethyl, (-)-menthol, (-)-α-methylbenzyl, or other acid stable protecting group.", "##STR11## Step (8) The compounds of the formula IX are treated with acetic acid, formic acid, triflouroacetic acid, sulfuric acid or the like or combinations thereof, preferably combinations of acetic acid and sulfuric acid to give the compounds of the formula X ##STR12## Step (9) The compounds of the formula X are treated to remove the carbamate functionalitity using methods known to those skilled in the art for example wherein R 5 is 2,2,2-trichloroethyl the compounds are treated with zinc dust in methanol, ethanol or the like, in the presence of acetic acid, to afford the compounds of the formula I wherein n is 2 or 3, m is 0 or 1, R 1 is hydrogen and R 2 and R 3 are as previously defined.", "Step (10) The compounds of the formula I wherein R 1 is hydrogen are treated with an aldehyde such as R formaldehyde, acetaldehyde, benzaldehyde or the like or with a ketone such as acetone, acetophenone, or the like, in the presence of a reducing agent such as sodium cyanoborohydride or the like, in a solvent such as methanol, ethanol or the like to give the compounds of the formula I wherein n is 2 or 3, m is 0 or 1, R 1 is as previously defined excepting hydrogen, and R 2 and R 3 are as previously defined.", "Step (11) Alternatively the compounds of the formula X are reduced in the presence of lithium aluminum hydride, diborane or the like, in a solvent such as ether, tetrahydrofuran or the like, to afford the compound of the formula I wherein R 1 is methyl.", "Novel intermediates useful in the preparation of compounds of formula I are: Spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one, 7'-methoxy-spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one, (+), (-), or (+/-)-3',4,-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-acetonitrile, (+), (-), or (+/-)-3',4,-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'acetonitrile, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]-2'-acetonitrile, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxy-6-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'acetonitrile, (+), (-), or (+/-)-2'-(2-aminoethyl)-3',4'-dihydrospiro[cyclopentane-1,1'(2H)-napthalen]-2'-ol, (+), (-), or (+/-)-2'-(2-aminoethyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-ol, (+), (-), or (+/-)-2'-(2-aminoethyl)-2',3'dihydrospiro[cyclopentane-1,1'-[1H]inden-2'-ol, (+), (-), or (+/-)-2'-(2-aminoethyl)-2',3'-dihydro-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden-2'-ol, Ethyl (+), (-), or (+/-)-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2,H)-naphthalen]2'-yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-naphthalen]-2'-yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-[2',3'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]2'-yl)ethyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[2-[2',3'-dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)ethyl)carbamate, Ethyl (+), (-), or (+/-)-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[g]indole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[g]indole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3,4,5-tetrahydro-8-methoxy-3a,9b-butano-1H-benz[g]indole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3-dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-2,3-dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate, (+), (-), or (+/-)-3',3",4',4"Tetrahydrodispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3',3",4',4"-Tetrahydro-7'-methoxydispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3",4"-Dihydrodispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3",4"-Dihydro-6'-methoxydispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one, (+), (-), or (+/-)-3',4'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'-propanamide, (+), (-), or (+/-)-3',4'-Dihydro-2'-hydroxy-7'methoxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'propanamide, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxyspiro-[cyclopentane-1,1'-[1H]indene]-2'-propanamide, (+), (-), or (+/-)-2',3'-Dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]indene]-2'-propanamide, (+), (-), or (+/-)-2'-(3-aminopropyl)-3',4'dihydrospiro[cyclopentane-1,1'(2'H)napthalen]-2'-ol, (+), (-), or (+/-)-2'-(3-aminopropyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)napthalen]2'-ol, (+), (-), or (+/-)-2'-(3-aminopropyl)-2',3'-dihydrospiro[cyclopentane-1,1'-[1H]inden]-2'-ol , (+), (-), or (+/-)-2'-(3-aminopropyl)-2',3'-dihydro-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-ol, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)napthlene]-2'-yl)propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(2',3'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-[3-(2',3'dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)-propyl]carbamate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4,5,6-tetrahydro-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4,5,6-tetrahydro-9-methoxy-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate, (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4-dihydro-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate, and (+), (-), or (+/-)-2,2,2-Trichloroethyl-3,4-dihydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate.", "The compounds of the instant invention exhibit valuable pharmacological properties by selectively blocking the N-methyl-D-aspartate sensitive excitatory amino acid receptors in mammals.", "The compounds are thus useful for treating diseases responsive to excitatory amino acid blockade in mammals.", "The effects are demonstrable in in vitro tests or in vivo animal tests using mammals or tissues or enzyme preparations thereof, e.g., mice, rats, or monkeys.", "The compounds are administered enterally or parenterally, for example, orally, transdermally, subcutaneously, intravenously, or intraperitoneally.", "Forms include but are not limited to gelatin capsules, or aqueous suspensions or solutions.", "The applied in vivo dosage may range between about 0.01 to 100 mg/kg, preferably between about 0.05 and 50 mg/kg, most preferably between about 0.1 and 10 mg/kg.", "The ability of the compounds of the instant invention to interact with phencyclidine (PCP) receptors which represents a noncompetitive NMDA antagonist binding site, is shown by Examples 23 and 27 which bind with an affinity of less than 10 μM.", "Tritiated 1-[1-(2-thienyl)cyclohexyl]pipiridine (TCP) binding, designated RBS1, was carried out essentially as described in J. Pharmacol.", "Exp.", "Ther.", "238, 739 (1986).", "For medical use, the amount required of a compound of formula I or pharmacologically acceptable salt thereof--(hereinafter referred to as the active ingredient) to achieve a therapeutic effect will, of course, vary both with the particular compound, the route of administration and the mammal under treatment and the particular disorder or disease concerned.", "A suitable systemic dose of a compound of formula I or pharmacologically acceptable salt thereof for a mammal suffering from, or likely to suffer from any condition as described herein before is in the range 0.01 to 100 mg of base per kilogram body weight, the most preferred dosage being 0.05 to 50 mg/kg of mammal body weight.", "It is understood that the ordinarily skilled physician or veterinarian will readily determine and prescribe the effective amount of the compound for prophylactic or therapeutic treatment of the condition for which treatment is administered.", "In so proceeding, the physician or veterinarian could employ an intravenous bolus followed by intravenous infusion and repeated administrations, parenterally or orally, as considered appropriate.", "While it is possible for an active ingredient to be administered alone, it is preferable to present it as a formulation.", "Formulations of the present invention suitable for oral administration may be in the form of discrete units such as capsules, cachets, tablets, or lozenges, each containing a predetermined amount of the active ingredient;", "in the form of a powder or granules;", "in the form of a solution or a suspension in an aqueous liquid or nonaqueous liquid;", "or in the form of an oil-in-water emulsion or a water-in-oil emulsion.", "The active ingredient may also be in the form of a bolus, electuary, or paste.", "A tablet may be made by compressing or molding the active ingredient optionally with one or more accessory ingredients.", "Compressed tablets may be prepared by compressing, in a suitable machine, the active ingredient in a free-flowing form such as a powder or granules, optionally mixed with a binder, lubricant, inert diluent, surface active, or dispersing agent.", "Molded tablets may be made by molding, in a suitable machine, a mixture of the powdered active ingredient and a suitable carrier moistened with an inert liquid diluent.", "Formulations suitable for parenteral administration conveniently comprise a sterile aqueous preparation of the active ingredient which is preferable isotonic with the blood of the recipient.", "Formulations suitable for nasal or buccal administration (such as self-propelling powder dispensing formulations described hereinafter), may comprise 0.1 to 20% w/w, for example, 2% w/w of active ingredient.", "The formulations, for human medical use, of the present invention comprise an active ingredient in association with a pharmaceuticaly acceptable carrier therefor and optionally other therapeutic ingredient(s).", "The carrier(s) must be `acceptable` in the sense of being compatible with the other ingredients of the formulations and not deleterious to the recipient thereof.", "So the pharmacologically active compounds of the invention are useful in the manufacture of pharmaceutical compositions comprising an effective amount thereof in conjunction or admixture with excipients or carriers suitable for either enteral or parenteral application.", "Preferred are tablets and gelatin capsules comprising the active ingredient together with a) diluents, e.g. lactose, dextrose, sucrose, mannitol, sorbitol, cellulose, and/or glycine;", "b) lubricants, e.g. silica, talcum, stearic acid, its magnesium or calcium salt, and/or polyethyleneglycol;", "for tablets also c) binders e.g. magnesium aluminum silicate, starch paste, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose and/or polyvinylpyrrolidone;", "if desired d) disintegrants, e.g. starches, agar, alginic acid, or its sodium salt, or effervescent mixtures;", "and/or e) absorbents, colorants, flavors, and sweeteners.", "Injectable compositions are preferably aqueous isotonic solutions or suspensions, and suppositories are advantageously prepared from fatty emulsions, or suspensions.", "Said compositions may be sterilized and/or contain adjuvants, such as preserving, stabilizing, wetting or emulsifying agents, solution promoters, salts for regulating the osmotic pressure, and/or buffers.", "In addition, they may also contain other therapeutically valuable substances.", "Said compositions are prepared according to conventional mixing, granulating, or coating methods, respectively, and contain about 0.1 to 75%, preferably about 1 to 50%, of the active ingredient.", "The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods well-known in the art of pharmacy.", "All methods include the step of bringing the active ingredient into association with the carrier which constitutes one or more accessory ingredients.", "In general, the formulations are prepared by uniformly and intimately bringing the active ingredient into association with a liquid carrier or a finely divided solid carrier or both, and then, if necessary, shaping the product into the desired formulation.", "The following examples are illustrative of the present invention but are not intended to limit it in any way.", "EXAMPLE 1 ##STR13## 3',4'-Dihydrospiro[cyclopentane-1,1'(2'H)-napthlen]-2'-one A suspension of KOt-Bu (76.3 g, 0.68 mol) in 500 mL of xylene was treated dropwise with 2-tetralone (50 g, 0.34 mol).", "The resulting solution was treated dropwise with 1,4-dibromobutane (74.0 g, 0.34 mol) (exothermic reaction).", "The resulting suspension was heated to reflux for 18h.", "The reaction mixture was treated with water (200 mL) and the organic phase was collected.", "The aqueous phase was extracted with ethyl acetate (2×200 mL) and the combined organic extracts were dried (MgSO 4 ), filtered and concentrated.", "Distillation of the residue provided the product (65.6 g, 96%) as a colorless liquid.", "EXAMPLE 2 ##STR14## 3',4'-Dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthlen]-2'-one In a manner similar to that described in Example 1, 7-methoxy-2-tetralone (20.0 g, 0.113 mol) was converted to the title compound (10.3 g, 40%) as a colorless oil.", "EXAMPLE 3 ##STR15## Spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one In a manner similar to that described in Example 1, 2-indanone is converted to the title compound.", "EXAMPLE 4 ##STR16## 6'-Methoxy-spiro[cyclopentane-1,1'-[1H]inden]-2'(3'H)-one In a manner similar to that described in Example 1, 5-methoxy-2-indanone is converted to the title compound.", "EXAMPLE 5 ##STR17## (+/-)-3',4+-Dihydro-2+-hydroxyspirocyclopentane-1,1'(2'H)-napthalen]-2'-acetonitrile A solution of acetonitrile (1.1 g, 27.5 mmol) in 100 mL of anhydrous tetrahydrofuran (THF) was cooled to -78° C. and treated with lithium diisopropylamide (18 mL of a 1.5M solution in tetrahydrofuran).", "The resulting suspension was stirred at -78° C. for 30 minutes and treated dropwise with a solution of the product from Example 1 (5.0 g, 24.9 mmol) in 10 mL of anhydrous THF.", "The resulting solution was warmed to room temperature and saturated aq.", "NH 4 Cl solution (15 mL) was added.", "The organic phase was collected and the aqueous phase was extracted with ether (3×50 mL).", "The combined organic phases were dried (MgSO 4 ), filtered and concentrated.", "The solid which formed was suspended in diisopropyl ether and collected by suction filtration.", "The material was dried under vacuum to give the title compound (4.14 g, 69%) as a white solid mp 165°-166° C. Anal.", "(C 16 H 19 NO) Calc'd: C, 79.63;", "H, 7.94;", "N, 5.80.", "Found: C, 79.72;", "H, 7.86;", "N, 5.81.", "EXAMPLE 6 ##STR18## (+/-)-3',4,-Dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-acetonitrile In a manner similar to that described in Example 5, the product of Example 2 (10.0 g, 43.4 mmol) was converted to the title compound (4.33 g, 37%) as a tan solid mp 126°-127° C. Anal.", "(C 17 H 21 NO 2 ) Calc'd: C, 75.25;", "H, 7.80;", "N, 5.16.", "Found: C, 75.36;", "H, 7.67;", "N, 4.94.", "EXAMPLE 7 ##STR19## (+/-)-2',3'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'-[1H]inden]-2'-acetonitrile In a manner similar to that described in Example 5, the product of Example 3 is converted to the title compound.", "EXAMPLE 8 ##STR20## (+/-)-2',3'-Dihydro-2'-hydroxy-6-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-acetonitrile In a manner similar to that described in Example 5, the product of Example 4 is converted to the title compound.", "EXAMPLE 9 ##STR21## (+/-)-2'-(2-Aminoethyl)-3',4'-dihydrospiro[cyclopentane-1,1'(2'H)-napthalen]-2'-ol A solution of the product from Example 5 (2.50 g, 10.3 mmol) in 100 mL of methanolic ammonia was hydrogenated over Raney nickel (2.0 g) at 52 psi for 7.5 hours.", "The reaction mixture was filtered to remove the catalyst and the filtrate concentrated to give the title compound (2.59 g, quantitative) as a pale green solid mp 107°-109° C. Anal (C 16 H 23 NO) Calc'd: C, 79.63;", "H, 7.94;", "N, 5.81.", "Found: C, 79.37;", "H, 8.02;", "N, 5.59.", "EXAMPLE 10 ##STR22## (+/-)-2'-(2-Aminoethyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-ol In a manner similar to that described for Example 9, the product of Example 6 (4.85 g, 17.9 mmol) was hydrogenated to give the title compound (4.86 g, 99%) as a pale green solid.", "Anal.", "(C 17 H 25 NO 2 ) Calc'd: C, 74.14;", "H, 9.15;", "N, 5.08.", "Found: C, 73.40;", "H, 9.19;", "N, 5.04.", "EXAMPLE 11 ##STR23## (+/-)-2'-(2-Aminoethyl)-2',3'-dihydrospiro[cyclopentane-1,1'-[1H]inden-2'-ol In a manner similar to that described for Example 9, the product of Example 7 is hydrogenated to give the title compound.", "EXAMPLE 12 ##STR24## (+/-)-2'-(2-Aminoethyl)-2',3'-dihydro-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden-2'-ol In a manner similar to that described for Example 9, the product of Example 8 is hydrogenated to give the title compound.", "EXAMPLE 13 ##STR25## Ethyl (+/-)-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthalen]-2'-yl)ethyl]carbamate A solution of the product from Example 9 (1.05 g, 4.28 mmol) and triethylamine (0.44 g, 4.35 mmol) in 10 mL of CH 2 Cl 2 was cooled to 0° C. and ethyl chloroformate (0.47 g, 4.33 mmol) in 5 mL CH 2 Cl 2 was added dropwise.", "The reaction was warmed to room temperature and washed with water.", "The aqueous phase was extracted with CH 2 Cl 2 (3×20 mL) and the combined organic extracts were dried (MgSO 4 ), filtered and concentrated.", "The residue was purified by chromatography (silica gel, 1:1 heptane/ethyl acetate) to give the title compound (1.33 g, 98%) as an oil.", "EXAMPLE 14 ##STR26## 2,2,2-Trichloroethyl (+/-)-[2-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-naphthalen]-2'-yl)ethyl]carbamate A solution of the product from Example 9 (0.88 g, 3.59 mmol) and triethylamine (0.40 g, 3.78 mmol) in 10 mL of CH 2 Cl 2 was cooled to 0° C. and treated dropwise with 2,2,2-trichloroethylchloroformate (0.80 g, 3.78 mmol) in 2 mL CH 2 Cl 2 .", "The resulting solution was stirred at 0° C. for 30 minutes and warmed to room temperature.", "The reaction mixture was washed with saturated aq.", "NaHCO 3 solution (10 mL).", "The aqueous phase was extracted with CH 2 Cl 2 (10 mL).", "The combined organic extracts were dried (MgSO 4 ), filtered and concentrated.", "The residue was purified by chromatography (silica gel, 10:1 heptane/ethyl acetate) to give the title compound (1.18 g, 78%) as a viscous oil.", "EXAMPLE 15 ##STR27## 2,2,2-Trichloroethyl (+/-)-[2-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-naphthalen]-2'-2'-yl)ethyl]carbamate In a manner similar to that described in Example 14, the product of Example 10 (4.66 g, 16.9 mmol) is converted to the title compound (6.81 g, 89%) as a foamy white solid.", "EXAMPLE 16 ##STR28## 2,2,2-Trichloroethyl (+/-)-[2-[2',3'-dihydro-2'-hydroxy-spiro[cyclopentane-1,1'-[1H]inden]-2'-yl)ethyl]carbamate In a manner similar to that described in Example 14, the product of Example 11 is converted to the title compound.", "EXAMPLE 17 ##STR29## 2,2,2-Trichloroethyl (+/-)-2-[2',3'-dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]inden]-2'-yl)ethyl]carbamate In a manner similar to that described in Example 14, the product of Example 12 is converted to the title compound.", "EXAMPLE 18 ##STR30## Ethyl (+/-)-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[q]indole-1-carboxylate A solution of the product from Example 13 (1.68 g, 5.29 mmol) in 15 mL of 3:1 acetic acid/concentrated sulfuric acid (v/v) was stirred at room temperature for 18 hours.", "The reaction mixture was poured into water (50 mL) and the resulting mixture was extracted with CH 2 Cl 2 (4×30 mL).", "The combined organic extracts were dried (MgSO 4 ), filtered and concentrated.", "The residue was dissolved in CH 2 Cl 2 (100 mL) and washed with saturated aq.", "bicarbonate solution (30 mL).", "The organic phase was dried (MgSPO 4 ), filtered and concentrated.", "The residue was purified by chromatography (silica gel, 9:1 heptane/ethyl acetate) to give the title compound (0.94 g, 59%) as a white solid mp 67°-69° C. Anal.", "(C 19 H 25 NO 2 ) Calc'd: C, 76.22;", "H, 8.42;", "N, 4.68.", "Found: C, 75.99;", "H, 8.38;", "N, 4.41.", "EXAMPLE 19 ##STR31## 0 2,2,2-Trichloroethyl (+/-)-2,3,4,5-tetrahydro-3a,9b-butano-1H-benz[q]indole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 14 (0.98 g, 2.33 mmol) was converted to the title compound (0.71 g, 76%) as an oil.", "EXAMPLE 20 ##STR32## 2,2,2-Trichloroethyl (+/-)-2,3,4,5-tetrahydro-8-methoxy-3a,9b-butano-1H-benz[q]indole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 15 (5.16 g, 11.4 mmol) was converted to the title compound (4.18 g, 84%) as an oil.", "EXAMPLE 21 ##STR33## 2,2,2-Trichloroethyl (+/-)-2,3-dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 16 is converted to the title compound.", "EXAMPLE 22 ##STR34## 2,2,2-Trichloroethyl (+/-)-2,3-dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole-1-carboxylate In a manner similar to that described in Example 18, the product of Example 17 is converted to the title compound.", "EXAMPLE 23 ##STR35## (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[q]indole hydrochloride A solution of the product from Example 19 (0.70 g, 1.74 mmol) in 20 mL of methanol and 0.5 mL acetic acid was treated with zinc dust (1.58 g, 320 mesh) and the resulting suspension stirred at room temperature for three hours.", "The reaction mixture was filtered and the filtrate concentrated.", "The residue was dissolved in ether (30 mL) and extracted with aqueous 1N HCl (3×15 mL).", "The combined acid extracts are made basic (pH=11) with potassium carbonate and the resulting aqueous solution was extracted with CH 2 Cl 2 (5×15 mL).", "The combined organic extracts were dried (Na 2 SO 4 ), filtered and concentrated.", "The residue (0.30 g) was converted to its HCl salt by dissolution in ether and treatment with a saturated solution of HCl (gas) in ether.", "The solid which formed was collected by filtration and dried under vacuum (100° C.) to give the title compound (0.25 g, 54%) as a white solid mp >270° C. Anal (C 16 H 19 N.HCl) Calc'd: C, 72.85;", "H, 8.40;", "N, 5.31;", "Cl, 13.44.", "Found: C, 72.66;", "H, 8.38, N, 4.98;", "Cl, 13.83.", "EXAMPLE 24 ##STR36## (+/-)-2,3,4,5-Tetrahydro-8-methoxy-3a,9b-butano-1H-benz]q]indole In a manner similar to that described in Example 23, the product of Example 20 (3.76 g, 8.67 mmol) was converted to the title compound 1.47 g, 70%) as an oil.", "An analytical sample was prepared by crystallization of the fumarate salt from acetone which gave a white solid mp 203°-204° C. Anal.", "(C 17 H 23 NO.", "C 4 H 4 O 4 ) Calc'd: C, 67.54;", "H, 7.29;", "N, 3.75.", "Found: C, 67.55;", "H, 7.18;", "N, 3.61.", "EXAMPLE 25 ##STR37## (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole In a manner similar to that described in Example 23, the product of Example 21 is converted to the title compound.", "EXAMPLE 26 ##STR38## (+/-)-2,3-Dihydro-7-methoxy-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole In a manner similar to that described in Example 23, the product of Example 22 is converted to the title compound.", "EXAMPLE 27 ##STR39## (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[q]indole hydrochloride A solution of the product from Example 18 (0.77 g, 2.56 mmol) in 5 mL of THF was added dropwise to a suspension of lithium aluminum hydride (0.76 g, 20.0 mmol) in 15 mL of THF.", "The reaction mixture was stirred at room temperature for 18 hours and then heated to reflux for 1 hour.", "The reaction mixture was cooled to room temperature and quenched by the addition of small portions of Na 2 SO 4 -10H 2 O until no further gas evolution was observed.", "The reaction mixture was filtered and the filtrate was concentrated.", "The residue was dissolved in ether and treated with a saturated solution of dry HCl in ether.", "The solid which formed was collected by suction filtration and dried under vacuum (100° C.) to give the product (0.51 g, 72%) as a white solid mp 241°-253° C. Anal.", "(C 17 H 23 N.HCl) Calc'd: C, 73.49;", "H, 8.71;", "N, 5.04;", "Cl, 12.76 .", "Found: C, 73.39;", "H, 8.73;", "N, 4.82;", "Cl, 13.16.", "EXAMPLE 28 ##STR40## (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1methyl-3a,9b-butano-1H-benz[q]indole A solution of the product from Example 24 (0.79 g, 3.08 mmol) and sodium cyanoborohydride (0.80 g, 12.7 mmol) in 10 mL methanol was treated dropwise with a 37% aqueous formalin solution (5 mL).", "The resulting solution was stirred at room temperature for 30 minutes, concentrated, and partitioned between 1N HCl (20 mL) and ether (20 mL).", "The organic phase was extracted with 1N HCl (2×10 mL) and the combined aqueous extracts were washed with ether.", "The aqueous phase was made basic with K 2 CO 3 and extracted with CH 2 Cl 2 (3×20 mL).", "The combined organic extracts were dried K 2 CO 3 , filtered and concentrated to give the title compound (0.87 g, quantitative) as a white solid mp 100°-102° C. Anal.", "(C 18 H 25 NO) Calc'd: C, 79.66;", "H, 9.29;", "N, 5.16.", "Found: C, 79.52;", "H, 9.53;", "N, 4.71.", "EXAMPLE 29 ##STR41## (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrole In a manner similar to that described in Example 28, the product of Example 25 is converted to the title compound.", "EXAMPLE 30 ##STR42## (+/-)-2,3-Dihydro-7-methoxy-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b)pyrrole In a manner similar to that described in Example 28, the product of Example 26 is converted to the title compound.", "EXAMPLE 31 ##STR43## (+/-)-2,3,4,5-Tetrahydro-1-ethyl-3a,9b-butano-1-benz[q]indole fumarate In a manner similar to that described in Example 28, the product from Example 23 (0.30 g, 1.32 mmol) and sodium cyanoborohydride (0.30 g, 4.77 mmol) was treated dropwise with acetaldehyde (0.20 g, 4.10 mmol) in 5 mL of methanol.", "Workup followed by crystallization of the fumarate salt from acetone gave the title compound (0.32 g, 65%) as a white solid mp 172°-173° C. Anal.", "(C 18 H 25 N.C 4 H 4 O 4 ) Calc'd: C, 71.13;", "H, 7.87;", "N, 3.77.", "Found: C, 70.90: H, 7.79;", "N, 3.75.", "EXAMPLE 32 ##STR44## (+/-)-2,3,4,5-Tetrahydro-8-methoxy-1-ethyl-3a,9b-butano-1H-benz[q]indole hydrobromide In a manner similar to that described in Example 31, the product of Example 24 (0.27 g, 1.13 mmol) and acetaldehyde (0.32 g, 7.12 mmol) are reacted.", "Workup, followed by crystallization from ether and HBr gave the title compound (0.27 g, 64%) as a white solid mp 248°-251° C. Anal.", "(C 19 H 27 NO.", "HBr) Calc'd: C, 62.29;", "H, 7.71;", "N, 3.82;", "Br, 21.81.", "Found: C, 62.39;", "H, 7.65;", "N, 3.77;", "Br, 21.98.", "EXAMPLE 33 ##STR45## (+/-)-2,3,4,5-Tetrahydro-1-propyl-3a,9b-butano-1H-benz[q]indole hydrobromide In a manner similar to that described in Example 32, the product from Example 23 (0.25 g, 1.10 mmol) and propionaldehyde (0.20 g, 3.47 mmol) was converted to the title compound (0.23 g, 60%) as a white solid mp 196°-198° C. Anal.", "(C 19 H 27 N.HBr) Calc'd: C, 64.92;", "H, 8.13;", "N, 4.07;", "Br, 23.09.", "Found: C, 65.14;", "H, 8.06;", "N, 4.00;", "Br, 22.80.", "EXAMPLE 34 ##STR46## (+/-)-2,3,4,5-tetrahydro-1-(cyclopropylmethyl)-3a,9b -butano-1H-benz[q]indole fumarate In a manner similar to that described in Example 31, the product from Example 23 (0.25 g, 1.10 mmol) and cyclopropanecarboxaldehyde (0.23 g, 1.10 mmol) was converted to the title compound (0.26 g, 58%) as a white solid mp 150°-152° C. Anal.", "(C 20 H 27 N[.", "].1.2C 4 H 4 O 4 ) Calc'd: C, 70.80;", "H, 7.62;", "N, 3.33.", "Found: C, 71.05;", "H, 7.67, N, 3.32.", "EXAMPLE 35 ##STR47## (+/-)-2,3,4,5-tetrahydro-1-phenylmethyl-3a,9b-butano-1H-benz[q]indole hydrochloride In a manner similar to that described in Example 32, the product from Example 23 (0.34 g, 1.50 mmol) and benzaldehyde are reacted.", "Workup, followed crystallization from ether and HCl gave the title compound (0.22 g, 42%) as a white solid mp 235°-237° C. Anal.", "(C 23 H 27 N.HCl) Calc'd C, 78.05;", "H, 7.98;", "N, 3.96;", "Cl, 10.02.", "Found: C, 77.60;", "H, 8.00, N, 3.34;", "Cl, 10.24.", "EXAMPLE 36 ##STR48## (+/-)-2,3,4,5-Tetrahydro-1-(2-propenyl)-3a,9b-butano-1H-benz[q]indole In a manner similar to that described in Example 32, the product from Example 23 is converted to the title compound.", "EXAMPLE 37 ##STR49## (+/-)-2,3,4,5-Tetrahydro-3a,9b-butano-1H-benz[q]indol-8-ol A solution of the product from Example 24 is heated to reflux in 48% aqueous HBr until the starting material is consumed.", "The reaction mixture is poured into cold NH 4 OH solution and extracted into ethyl acetate.", "The combined organic extracts are dried (Na 2 SO 4 ) and concentrated to give the title compound.", "EXAMPLE 38 ##STR50## (+/-)-2,3,4,5-Tetrahydro-1-methyl-3a,9b-butano-1H-benz[q]indol-8-ol In a manner similar to that described in Example 37, the product from Example 28 is converted to the title compound.", "EXAMPLE 39 ##STR51## (+/-)-2,3-Dihydro-1H,4H-3a,8b-butanoindeno[1,2-b]pyrrol-7-ol In a manner similar to that described in Example 37, the product from Example 26 is converted to the title compound.", "EXAMPLE 40 ##STR52## (+/-)-2,3-Dihydro-1-methyl-1H,4H-3a,8b-butanoindeno[1,2-b]-pyrrol-7-ol In a manner similar to that described in Example 37, the product from Example 30 is converted to the title compound.", "EXAMPLE 41 ##STR53## 3',3",4',4"-Tetrahydrodispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)-furan]-5"-one A solution of triethylsilyl N,N,N',N'-tetramethyl phosphoramidate (J.", "Amer.", "Chem.", "Soc.", "1978, 100, 3468) (1.1 eq.) in anhydrous ether is cooled to 0° C. and treated with acrolein (1.0 eq.) in anhydrous ether.", "The resulting solution is stirred at 0° C. for 4.5 hours then cooled to -78° C. and a solution of n-butyllithium (1.0 eq.) is added.", "The resulting solution is treated with the product from Example 1 (1.0 eq.) and stirred at -78° C. for several hours.", "The reaction mixture is quenched with brine and extracted with several portions of ether.", "The combined extracts are dried and concentrated.", "The residue is dissolved in THF and cooled to 0° C. and tetra-n-butylammonium flouride (5 eq.) is added.", "The reaction mixture is warmed to room temperature and worked up as above to give the title compound.", "EXAMPLE 42 ##STR54## 3',3",4',4"-Tetrahydro-7'-methoxydispiro[cyclopentane-1,1'(2'H)-napthlene-2',2"(5"H)furan]-5"-one In a manner similar to that described in Example 41, the product from Example 2 is converted to the title compound.", "EXAMPLE 43 ##STR55## 3",4"-Dihydrodispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one In a manner similar to that described in Example 41, the product from Example 3 is converted to the title compound.", "EXAMPLE 44 ##STR56## 3",4"-Dihydro-6'-methoxydispiro[cyclopentane-1,1'-[1H]indene-2'(3'H),2"(5"H)-furan]-5"-one In a manner similar to that described in Example 41, the product from Example 4 is converted to the title compound.", "EXAMPLE 45 ##STR57## (+/-)-3',4'-Dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'-propanamide A solution of the product from Example 41 is placed in a high pressure reactor and dissolved in tetrahydrofuran.", "Ammonia is condensed into the solution and the reaction vessel is sealed and the reaction mixture is stirred at room temperature for approximately 24 hours.", "The reaction vessel is vented and the remaining solvent is concentrated to give the title compound.", "EXAMPLE 46 ##STR58## (+/-)-3',4'-Dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-naphthalene]-2'-propanamide In a manner similar to that described in Example 45, the product from Example 42 is converted to the title compound.", "EXAMPLE 47 ##STR59## (+/-)-2',3'-Dihydro-2,-hydroxyspiro[cyclopentane-1,1'-[1H]indene]-2,-propanamide In a manner similar to that described in Example 45, the product from Example 43 is converted to the title compound.", "EXAMPLE 48 ##STR60## (+/-)-2',3'-Dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'-[1H]indene]-2'-propanamide In a manner similar to that described in Example 45, the product from Example 44 is converted to the title compound.", "EXAMPLE 49 ##STR61## (+/-)-2'-(3-Aminopropyl)-3',4'-dihydrospiro[cyclopentane-1,1'(2'H)napthalen]-2'-ol A solution of the product from Example 45, in tetrahydrofuran (THF) is added dropwise to a suspension of lithium aluminumhydride in THF.", "The resulting suspension is heated to reflux for 1 hour and then stirred at room temperature for 18 hours.", "The reaction mixture is quenched by the addition of small portions of Na 2 SO 4 -10H 2 O until no more gas evolution is observed.", "The resulting suspension is filtered and the filtrate is concentrated to give the title compound.", "EXAMPLE 50 ##STR62## (+/-)-2'-(3-Aminopropyl)-3',4'-dihydro-7'-methoxyspiro[cyclopentane-1,1'(2'H)napthalen]-2'-ol In a manner similar to that described in Example 49, the product from Example 46 is converted to the title compound.", "EXAMPLE 51 ##STR63## (+/-)-2'-(3-Aminopropyl)-2',3'-dihydrospiro[cyclopentane-1,1'-[1H]inden]-2'-ol In a manner similar to that described in Example 49, the product from Example 47 is converted to the title compound.", "EXAMPLE 52 ##STR64## (+/-)-2'-(3-Aminopropyl)-2',3'-dihydro-6'-methoxyspiro[[cyclopentane-1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate In a manner similar to that described in Example 49, the product from Example 48 is converted to the title compound.", "EXAMPLE 53 ##STR65## 2,2,2-Trichloroethyl (+/-)-3-(3',4'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate A solution of the product from Example 49 (1.0 eq.) and triethylamine (1.1 eq.) in CH 2 Cl 2 is cooled to 0° C. and a solution of 2,2,2-trichloroethylchloroformate (1.1 eq.) in CH 2 Cl 2 is added dropwise.", "The resulting solution is stirred at 0° C. for 30 minutes and warmed to room temperature.", "The reaction mixture is washed with bicarbonate, dried and concentrated to give the title compound.", "EXAMPLE 54 ##STR66## 2,2,2-Trichloroethyl (+/-)-[3-(3',4'-dihydro-2'-hydroxy-7'-methoxyspiro[cyclopentane-1,1'(2'H)-napthlene]-2'-yl)propyl]carbamate In a manner similar to that described in Example 53, the product from Example 50 is converted to the title compound.", "EXAMPLE 55 ##STR67## 2,2,2-Trichloroethyl (+/-)-[3-(2',3'-dihydro-2'-hydroxyspiro[cyclopentane-1,1'[1H]inden]-2'-yl)propyl]carbamate In a manner similar to that described in Example 53, the product from Example 51 is converted to the title compound.", "EXAMPLE 56 ##STR68## 2,2,2-Trichloroethyl (+/-)-[3-(2',3'-dihydro-2'-hydroxy-6'-methoxyspiro[cyclopentane-1,1'[1H]inden]-2'-yl)propyl]carbamate In a manner similar to that described in Example 53, the product from Example 52 is converted to the title compound.", "EXAMPLE 57 ##STR69## 2,2,2-Trichloroethyl (+/-)-3,4,5,6-tetrahydro-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 53 is converted to the title compound.", "EXAMPLE 58 ##STR70## 2,2,2-Trichloroethyl (+/-)-3,4,5,6-tetrahydro-9-4a,10b-butanobenz[h]quinoline-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 54 is converted to the title compound.", "EXAMPLE 59 ##STR71## 2,2,2-Trichloroethyl (+/-)-3,4-dihydro-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 55 is converted to the title compound.", "EXAMPLE 60 ##STR72## 2,2,2-Trichloroethyl (+/-)-3,4-dihydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine-1(2H)-carboxylate In a manner similar to that described in Example 18, the product from Example 56 is converted to the title compound.", "EXAMPLE 61 ##STR73## (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinoline In a manner similar to that described in Example 23, the product from Example 57 is converted to the title compound.", "EXAMPLE 62 ##STR74## (+/-)-1,2,3,4,5,6-Hexahydro-9-methoxy-4a,10b-butanobenz[h]-quinoline In a manner similar to that described in Example 23, the product from Example 58 is converted to the title compound.", "EXAMPLE 63 ##STR75## (+/-)-1,2,3,4-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 23, the product from Example 59 is converted to the title compound.", "EXAMPLE 64 ##STR76## (+/-)-1,2,3,4-Tetrahydro-8-methoxy-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 23, the product from Example 60 is converted to the title compound.", "EXAMPLE 65 ##STR77## (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a,10b-butanobenz[h]quinoline In a manner similar to that described in Example 28, the product from Example 61 is converted to the title compound.", "EXAMPLE 66 ##STR78## (+/--)-1,2,3,4,5,6-Hexahydro-9-methoxy-1-methyl-4a,10b-butanobenz[h]quinoline In a manner similar to that described in Example 28, the product from Example 62 is converted to the title compound.", "EXAMPLE 67 ##STR79## (+/-)-1,2,3,4-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 28, the product from Example 63 is converted to the title compound.", "EXAMPLE 68 ##STR80## (+/-)-1,2,3,4-Tetrahydro-8-methoxy-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridine In a manner similar to that described in Example 28, the product from Example 64 is converted to the title compound.", "EXAMPLE 69 ##STR81## (+/-)-1,2,3,4,5,6-Hexahydro-4a,10b-butanobenz[h]quinoline-9-ol In a manner similar to that described in Example 37, the product from Example 62 is converted to the title compound.", "EXAMPLE 70 ##STR82## (+/-)-1,2,3,4,5,6-Hexahydro-1-methyl-4a,10b-butanobenz[h]quinoline-9-ol In a manner similar to that described in Example 37, the product from Example 64 is converted to the title compound.", "EXAMPLE 71 ##STR83## (+/-)-1,2,3,4-Tetrahydro-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol In a manner similar to that described in Example 37, the product from Example 66 is converted to the title compound.", "EXAMPLE 72 ##STR84## (+/-)-1,2,3,4-Tetrahydro-1-methyl-4a,9b-butano-5H-indeno[1,2-b]pyridin-8-ol In a manner similar to that described in Example 37, the product from Example 68 is converted to the title compound." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims benefit from U.S. Provisional Patent Application Ser. No. 60/566,259, filed Apr. 29, 2004, and also U.S. Provisional Patent Application Ser. No. 60/604,639, filed Aug. 26, 2004, which applications are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] This invention relates generally to the therapeutic devices and, in particular, to a device which promotes reflective neuromuscular training. [0004] 2. Description of the Related Art [0005] Devices which are used to strengthen, rehabilitate, and exercise the feet, ankles, and lower extremities are commonplace today. One type of these devices are generally used for exercising and strengthening the foot. For example, U.S. Pat. No. 1,962,971, which issued in 1934, describes a foot treating device comprising a conoidal-shaped body of flexible resilient material terminating in flanges of sufficient radial extent to bear laterally against and massage the sides of the foot when rolled, exercising the muscles and stimulating weakened nerve tissues. U.S. Pat. No. 2,510,193, which issued in 1950, describes a foot exerciser which is rolled beneath the feet to exercise the feet to cause the weakened muscles and bones of the feet to return to their normal positions and strengthen them in their positions. U.S. Pat. No. 2,465,725, which issued in 1949, is directed to a foot exerciser pad consisting of a multiplicity of resilient, button-like members, preferably of uniform size which exercises the muscles of the feet and legs by rocking the feet as the rounded buttons occupying the spaces formed by the arches of the feet. U.S. Pat. No. 2,820,454, which issued in 1958, is directed to a foot kneading rug comprised of a base pad of sponge rubber on which hard buttons are mounted in distributed arrangement, where the buttons are of spherical segmental shape of a thickness approximated equal to the thickness of the sponge rubber pad. The composite surface formed by the rounded upper portions of the hard buttons and the intervening soft depressions formed by the exposed upper surface of the pad is covered intimately by a cover membrane forming the rug tread. [0006] While these devices are capable of exercising and strengthening the muscles of the feet, they do not develop proprioception. Proprioception involves neuromuscular receptors in the skeletal muscles on the surface of the tendons. These receptors provide constant feedback to the brain regarding movement, posture, changes in equilibrium, knowledge of position, weight and resistance against its body parts. Special devices have been developed in recent times which address this function. U.S. Pat. No. 6,551,225, which issued in 2003, is directed to a balancing exercise device having a flexible hemisphere having a flat circular surface and a hemispherical side surface and attachment straps such that a body part is held against the flat circular surface. Constant variations of movement in any and all directions of the hemispherical surface put different stretch on the tendons, muscles, ligaments and joints and thereby stimulates increased numbers of proprioceptors and nerve cells of the body parts. U.S. Pat. No. 6,811,523, which issued in 2004, describes a lower extremity rehabilitation and exercise device having a platform to which at least one foot is secured. A fulcrum is placed beneath the platform at various locations which correspond to particular muscles or muscle groups which are stressed while the exercise is performed, building strength in the muscles, while also developing proprioception within the stressed muscle or muscle group during the exercise. While these devices are relatively simple to use, they rely on balancing the body on a flat surface which is mounted upon a hemispherical shape while the feet are strapped to a flat surface. [0007] Another type of device has also been developed for the purpose of improving proprioception in the user. U.S. Pat. No. 5,613,690, which issued in 1997, describes a training and enhancement device to improve the balance and proprioceptive abilities of the user. A balance platform is placed atop a base platform, with the balance platform being angularly displaceable in any direction relative to the base. The device is connected to a personal computer through sensors, providing feedback to determine angular displacement of the user. U.S. Patent Application Publication No. 2003/0199374, which was published in 2003, describes a proactive machine for assessing and improving a user's proprioception. The device has a tilting platform upon which the user stands, a non-rotating tilting means connected to the platform for tilting the platform along several axes, and a control for controlling the tilting. While these devices are designed specifically for promoting proprioception improvement, these are relatively complex and expensive to purchase. SUMMARY OF THE INVENTION [0008] It is therefore an object of the present invention to provide a therapeutic device which is inexpensive and portable. [0009] It is a further object of the present invention to provide a rehabilitative device for promoting improved balance and proprioception training in the feet, ankles, knees and hips. [0010] It is a still further object of the present invention to provide a device which may be incorporated into an exercise routine for enhancing balance and proprioception. [0011] It is a still further object of the present invention to provide a device which provides preloading of the soft tissues of the foot and ankle prior to exercising to prevent injury to these areas. [0012] These and other objects of the present invention will become readily apparent from the description and drawings which follow. BRIEF DESCRIPTION OF THE DRAWINGS [0013] FIG. 1 is a side elevational view of a device according to the present invention; [0014] FIG. 2 is a side elevational view of an alternative embodiment according to the present invention; [0015] FIG. 3 is a front elevational view of the device shown in FIG. 1 in use; [0016] FIG. 4 is a side elevational view of the device shown in FIG. 2 in use; and [0017] FIG. 5 is a top plan view of another alternative embodiment of the present invention for use in rehabilitation of a patient. DESCRIPTION OF THE PREFERRED EMBODIMENT [0018] Balance and postural control are complex processes that rely on input from three systems: the visual system, which orients oneself to an object, the vestibular system, which orients oneself to gravity, and the somatosensory system, which refers to the premeditated and/or the unconscious awareness of joint position. This plays an important role in the prevention of injury, as well as in maintaining the integrity of joint and surrounding anatomical structures. Sensory receptors for proprioception relay the status of articular (oint) structures. These receptors, or fibers, are found in the skin, muscles, joints, joint capsule, ligaments, and tendons, and send information to the central nervous system concerning joint movement (kinesthesia) and joint position (proprioception). Four types of joint sensory fibers have been identified, each serving a specific role in sensorymotor function and joint proprioception: type I fibers (located in the joint capsule) provide information concerning static (stationary) position and help regulate postural muscle tone; type 11 fibers (located in joint capsule) detect quick changes in movement and provide information concerning acceleration and deceleration of joint components; type III fibers (located in the intrinsic and extrinsic joint ligaments) monitor direction of movement and have a reflex effect on muscle tone to prevent excessive motion or displacement of the joint; and type IV fibers (located in the capsule, and intrinsic and extrinsic ligaments) are inactive under normal circumstances, but may be activated when related tissue is subjected to marked deformation or other noxious mechanical or chemical stimulation. Skin connective tissue and muscle nerve endings (mechanoreceptors) may also contribute information in these ways. [0019] Sensory (afferent) information is relayed to the central nervous system via the sensory receptors previously discussed, is processed by the brain, and an appropriate motor response is initiated to maintain balance or stabilize a joint. Two motor control mechanisms are involved with interpreting afferent information and coordinating an efferent (to joint structures) response; feed-forward and feedback. Feed-forward involves planning movements based on sensory information from past experiences (preparatory muscle activity). This pre-activation theory suggests that prior sensory experiences concerning a task are used to form muscle activity patterns. In this way, sensory feedback from the past is fed forward to pre-program muscle responses. The feed-forward mechanism causes pre- activated muscles to provide quick compensation for external loads, which is critical to dynamic joint stability. The feedback mechanism continuously regulates motor control through reflex pathways and reactive muscle activity. Information from joint and muscle structures is used reflexively to synchronize motor responses to complete a task. The feedback process is best used to maintain posture and regulate slow movements. The influence of this process on dynamic joint stabilization is dependent upon the speed and magnitude of joint perturbations. Both feed-forward and feedback mechanisms enhance joint stability if these motor pathways are frequently stimulated by way of proprioceptive or rehabilitative training. With repetitive stimuli, these pathways create memory in the joint for future movements. [0020] At the joint structural level, individuals who are well-conditioned have better joint motion and position sense than those who are deconditioned. The deconditioned persons lack adequate somatosensory awareness to coordinate muscle activity and dynamic joint stability, and may be subject to injury. Speed and complexity of movement in activities of daily living rely on rapid integration of sensory information by the feed-forward and feedback mechanisms. Without sufficient preliminary activity, or training, structures of the joint and extremity may become vulnerable to damage. An injury, mechanical or disease-related, causes partial deafferentation (decreased sensory input) of the joint. Deafferentation is a decreased afferent neural signal, and is described as a proprioceptive deficit. Decreased proprioceptive signals inhibit normal motor response and balance reactions and decrease neuromuscular stabilizations of the joint, which may lead to injury or further damage of joint structures. [0021] The purpose of neuromuscular rehabilitation for proprioceptive deficits is to incorporate peripheral sensory input relative to joint position, and to process these signals into efferent motor responses. Once proprioceptive deficits have been identified, they need to be corrected in order to prevent episodes of functional instability and repetitive injury. Rehabilitation for these deficits should encourage preparatory agonist (contracting) and antagonist (opposing) muscle activity. Effective co-activation restores the force couples required to balance joint forces and increases congruency, thus reducing loads on joint structures. In a controlled rehabilitation exercise, the placement of joints in vulnerable, or unstable, positions helps re-establish proprioception and appropriate motor responses. These stabilizing responses of muscles require sensory anticipation of joint displacement and joint loads. Therefore, neuromuscular and balance training focus upon stimulating the sensory pathways from joint structures to the central nervous system. Frequent or repetitive use of these pathways has been shown to decrease response time and develop reaction strategies for unexpected events. Reflex-mediated muscle activity is a crucial element of the functionally stable joint and should complement pre-programmed activity. Proprioceptive rehabilitation should focus upon neuromuscular training by stimulating the reflex pathways from joint structures (ligaments, tendons, cartilage, capsule, epidermis) and surrounding muscles that act as static and dynamic stabilizers. Therefore, proprioceptive and balance exercises should provoke joint perturbations (alterations of position) to facilitate reflex muscle activation and postural control. By creating postural and/or dynamic imbalance, these rehabilitation activities encourage automatic and appropriate neuromuscular responses. Thus, these types of exercise should be initiated early in all rehabilitation programs. Patient involvement, by way of home exercises and exercise tools, is also critical to the success of the rehabilitation program. [0022] It is important, finally, to mention the role of proprioceptive and balance training in post-surgical or post-injury tissue healing. Research has indicated that joint structures increase in strength linear to stresses put upon them (Wolfe's Law) and, also, that there is a strong relationship between joint injury and subsequent loss of motor control. It is essential, then, to stress these structures in a functional manner during rehabilitation to promote the proper orientation of joint tissue fibers during healing. Selective proprioceptive exercises which simulate realistic tasks can encourage healing of tissues in the same orientation of functional stresses applied to the joints with everyday activities. Thus, proprioceptive training provides a protective mechanism against re-injury with return to activity. [0023] The present invention comprises materials, or tools, used to elicit joint perturbations and therefore promote reflective neuromuscular training. The dense, irregular foam rubber and rock-like shape of the device provides a means of stressing or compressing different soft tissues of the foot, or any other extremity, placed upon them. Depending upon the position of the extremity of the device's surface, muscle activation occurs through proprioceptive information to the central nervous system and muscular response to maintain joint stability near stressed structures. At the same time, reciprocal inhibition (relaxation of antagonist muscle) occurs in the muscle groups not stressed. (i.e. quadriceps contract, hamstrings relax) This co-activation of muscle groups helps to balance the forces surrounding the joint, and, as research has shown, plays a key role in prevention of injury to susceptible tissues (i.e. a knee after ligament surgery). Lastly, the forces applied to the distal (furthest end from the torso) extremity by way of the device also provides neuromuscular training for more proximal (closest end to the torso) structures. Activity from these proximal structures is required to maintain overall balance and postural stability. Therefore, forces from the device applied to the foot, or hand, can provide neuromuscular training for the ankle, knee, and hip, or the forearm, elbow, and shoulder. Many studies have documented that the body does not function as a rigid segment, but as a multi-link structure; events surrounding the distal segment of an extremity affect those located more proximally in the kinetic chain. Thus, the use of the incongruent surface of the device is a crucial element in retraining the sensory pathways to the central nervous system from multiple anatomical structures, so that this information may be stored and retrieved at the appropriate time in the future (with return to activity or sport). The various sizes and points of application of the device provides a multitude of opportunities for this type of physical rehabilitation. Finally, the fact that the device is both affordable and easily transported make it an ideal home exercise tool, which could complement virtually any neuromuscular or orthopaedic training program. [0024] Referring now to FIG. 1 , there is shown a device, generally indicated at 10 , which embodies the present invention. Device 10 contains a planar lower surface 12 for positioning device 10 on a flat horizontal surface such as the floor or an exercise mat. Upper region 14 of device 10 comprises an irregular incongruent surface. Device 10 is preferably constructed from a dense foam rubber which moderately compresses when subjected to the weight of a user. The incongruent surface may contain certain surface features, such as a concave or convex section, in areas of the surface to enhance proprioception training for specific areas of the body. [0025] FIG. 3 shows device 10 in use, with the foot 20 of a user standing on device 10 . Note that the irregular surface 14 allows some compression of device 10 , causing various points of application to the bones, muscles and tendons of the user's foot. When the user balances on one foot on device 10 , the brain sends messages to various muscles of the body, instructing them to correct the instability. In this manner, proprioceptive deficits can be rehabilitated. If the user looks from side to side while balanced, additional proprioceptive information will be sent to the central nervous system, and reaction to this stimulus creates additional rehabilitative effects. [0026] FIG. 2 displays an alternative device 10 ′, which exhibits a different upper region 14 ′ that is shown in FIG. 1 . The overall size of device 10 ′ may be smaller than device 10 , and is preferably constructed of a denser foam rubber which has less compressibility. Device 10 ′ does have a planar lower surface 12 , such that it can be positioned solidly on the floor. When a user's foot 12 is placed upon device 10 ′ and the body is balanced on foot 12 , different sensory stimulation is accomplished, as the firmness and orientation of device 10 ′, in addition to its non-uniformity of its outer top surface, are different than that of device 10 . [0027] FIG. 4 shows the device of FIG. 3 in use, where the user locates device 10 ′ in the mid-foot area. By using the device under different sections of the foot, such as rear foot, mid-foot, and forefoot, other areas of the body including the ankle, knee, and hip structures may be stressed. [0028] In addition to stretching the muscles of the foot, which is desirable in sports such as running, proprioceptive balance is promoted not only in the foot, but also in the ankle, knee and hip joint. [0029] This preloading of the soft tissues of the foot and ankle prior to exercising helps to prevent injury to these areas. [0030] One goal of proprioceptive/balance training is to return patients to their maximum prior level of function. Therefore, systems can be designed containing multiple proprioceptive and a balance related challenges specifically to promote reflective neuromuscular training for any individual. Such a system is shown in FIG. 5 . Referring now to FIG. 5 , a training system designated at 30 consists of a plurality of interchangeable interlocking mats of pads 32 which can be assembled to maximize the rehabilitative regimen of each patient. In the center of each pad is a version 10 a - f of the device shown in FIGS. 1 and 3 . System 30 contains a mix of multiple proprioceptive and balance related challenges. Each pad 32 differs in degree of proprioceptive/balance difficulty on its surface. For example, 10 a and 10 d devices may contain a mild degree of difficulty, 10 b and 10 e devices contain a moderate degree of difficulty, and 10 c and 10 f devices contain a severe degree of difficulty. Each device may contain an indicia which denotes the degree of difficulty, such as red for simple, blue for difficult, etc. In this manner, clinicians can construct a course using different segments, depending on the patient's needs. In addition, other compliant surfaces, such as a grasslike surface, or obstacle to step over and around can be inserted into the system to elicit certain neuromuscular responses to suit the patient's needs. System 30 can be used to simulate the everchanging proprioceptive and balance changes in the environment which patients face every day during the activities of daily living. [0031] While this invention has been shown and described in terms of a preferred embodiment, it will be understood that this invention is not limited to this particular embodiment, and that many changes and modifications may be made without departing from the true spirit and scope of the invention as defined in the appended claims.
A device for promoting reflective neuromuscular training. The device is a moderately compressible member having a planar lower surface and an incongruent upper surface. When used in proprioceptive rehabilitation, the device stimulates sensory pathways to improve balance and neuromuscular responses.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims benefit from U.S. Provisional Patent Application Ser.", "No. 60/566,259, filed Apr. 29, 2004, and also U.S. Provisional Patent Application Ser.", "No. 60/604,639, filed Aug. 26, 2004, which applications are incorporated herein by reference.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] This invention relates generally to the therapeutic devices and, in particular, to a device which promotes reflective neuromuscular training.", "[0004] 2.", "Description of the Related Art [0005] Devices which are used to strengthen, rehabilitate, and exercise the feet, ankles, and lower extremities are commonplace today.", "One type of these devices are generally used for exercising and strengthening the foot.", "For example, U.S. Pat. No. 1,962,971, which issued in 1934, describes a foot treating device comprising a conoidal-shaped body of flexible resilient material terminating in flanges of sufficient radial extent to bear laterally against and massage the sides of the foot when rolled, exercising the muscles and stimulating weakened nerve tissues.", "U.S. Pat. No. 2,510,193, which issued in 1950, describes a foot exerciser which is rolled beneath the feet to exercise the feet to cause the weakened muscles and bones of the feet to return to their normal positions and strengthen them in their positions.", "U.S. Pat. No. 2,465,725, which issued in 1949, is directed to a foot exerciser pad consisting of a multiplicity of resilient, button-like members, preferably of uniform size which exercises the muscles of the feet and legs by rocking the feet as the rounded buttons occupying the spaces formed by the arches of the feet.", "U.S. Pat. No. 2,820,454, which issued in 1958, is directed to a foot kneading rug comprised of a base pad of sponge rubber on which hard buttons are mounted in distributed arrangement, where the buttons are of spherical segmental shape of a thickness approximated equal to the thickness of the sponge rubber pad.", "The composite surface formed by the rounded upper portions of the hard buttons and the intervening soft depressions formed by the exposed upper surface of the pad is covered intimately by a cover membrane forming the rug tread.", "[0006] While these devices are capable of exercising and strengthening the muscles of the feet, they do not develop proprioception.", "Proprioception involves neuromuscular receptors in the skeletal muscles on the surface of the tendons.", "These receptors provide constant feedback to the brain regarding movement, posture, changes in equilibrium, knowledge of position, weight and resistance against its body parts.", "Special devices have been developed in recent times which address this function.", "U.S. Pat. No. 6,551,225, which issued in 2003, is directed to a balancing exercise device having a flexible hemisphere having a flat circular surface and a hemispherical side surface and attachment straps such that a body part is held against the flat circular surface.", "Constant variations of movement in any and all directions of the hemispherical surface put different stretch on the tendons, muscles, ligaments and joints and thereby stimulates increased numbers of proprioceptors and nerve cells of the body parts.", "U.S. Pat. No. 6,811,523, which issued in 2004, describes a lower extremity rehabilitation and exercise device having a platform to which at least one foot is secured.", "A fulcrum is placed beneath the platform at various locations which correspond to particular muscles or muscle groups which are stressed while the exercise is performed, building strength in the muscles, while also developing proprioception within the stressed muscle or muscle group during the exercise.", "While these devices are relatively simple to use, they rely on balancing the body on a flat surface which is mounted upon a hemispherical shape while the feet are strapped to a flat surface.", "[0007] Another type of device has also been developed for the purpose of improving proprioception in the user.", "U.S. Pat. No. 5,613,690, which issued in 1997, describes a training and enhancement device to improve the balance and proprioceptive abilities of the user.", "A balance platform is placed atop a base platform, with the balance platform being angularly displaceable in any direction relative to the base.", "The device is connected to a personal computer through sensors, providing feedback to determine angular displacement of the user.", "U.S. Patent Application Publication No. 2003/0199374, which was published in 2003, describes a proactive machine for assessing and improving a user's proprioception.", "The device has a tilting platform upon which the user stands, a non-rotating tilting means connected to the platform for tilting the platform along several axes, and a control for controlling the tilting.", "While these devices are designed specifically for promoting proprioception improvement, these are relatively complex and expensive to purchase.", "SUMMARY OF THE INVENTION [0008] It is therefore an object of the present invention to provide a therapeutic device which is inexpensive and portable.", "[0009] It is a further object of the present invention to provide a rehabilitative device for promoting improved balance and proprioception training in the feet, ankles, knees and hips.", "[0010] It is a still further object of the present invention to provide a device which may be incorporated into an exercise routine for enhancing balance and proprioception.", "[0011] It is a still further object of the present invention to provide a device which provides preloading of the soft tissues of the foot and ankle prior to exercising to prevent injury to these areas.", "[0012] These and other objects of the present invention will become readily apparent from the description and drawings which follow.", "BRIEF DESCRIPTION OF THE DRAWINGS [0013] FIG. 1 is a side elevational view of a device according to the present invention;", "[0014] FIG. 2 is a side elevational view of an alternative embodiment according to the present invention;", "[0015] FIG. 3 is a front elevational view of the device shown in FIG. 1 in use;", "[0016] FIG. 4 is a side elevational view of the device shown in FIG. 2 in use;", "and [0017] FIG. 5 is a top plan view of another alternative embodiment of the present invention for use in rehabilitation of a patient.", "DESCRIPTION OF THE PREFERRED EMBODIMENT [0018] Balance and postural control are complex processes that rely on input from three systems: the visual system, which orients oneself to an object, the vestibular system, which orients oneself to gravity, and the somatosensory system, which refers to the premeditated and/or the unconscious awareness of joint position.", "This plays an important role in the prevention of injury, as well as in maintaining the integrity of joint and surrounding anatomical structures.", "Sensory receptors for proprioception relay the status of articular (oint) structures.", "These receptors, or fibers, are found in the skin, muscles, joints, joint capsule, ligaments, and tendons, and send information to the central nervous system concerning joint movement (kinesthesia) and joint position (proprioception).", "Four types of joint sensory fibers have been identified, each serving a specific role in sensorymotor function and joint proprioception: type I fibers (located in the joint capsule) provide information concerning static (stationary) position and help regulate postural muscle tone;", "type 11 fibers (located in joint capsule) detect quick changes in movement and provide information concerning acceleration and deceleration of joint components;", "type III fibers (located in the intrinsic and extrinsic joint ligaments) monitor direction of movement and have a reflex effect on muscle tone to prevent excessive motion or displacement of the joint;", "and type IV fibers (located in the capsule, and intrinsic and extrinsic ligaments) are inactive under normal circumstances, but may be activated when related tissue is subjected to marked deformation or other noxious mechanical or chemical stimulation.", "Skin connective tissue and muscle nerve endings (mechanoreceptors) may also contribute information in these ways.", "[0019] Sensory (afferent) information is relayed to the central nervous system via the sensory receptors previously discussed, is processed by the brain, and an appropriate motor response is initiated to maintain balance or stabilize a joint.", "Two motor control mechanisms are involved with interpreting afferent information and coordinating an efferent (to joint structures) response;", "feed-forward and feedback.", "Feed-forward involves planning movements based on sensory information from past experiences (preparatory muscle activity).", "This pre-activation theory suggests that prior sensory experiences concerning a task are used to form muscle activity patterns.", "In this way, sensory feedback from the past is fed forward to pre-program muscle responses.", "The feed-forward mechanism causes pre- activated muscles to provide quick compensation for external loads, which is critical to dynamic joint stability.", "The feedback mechanism continuously regulates motor control through reflex pathways and reactive muscle activity.", "Information from joint and muscle structures is used reflexively to synchronize motor responses to complete a task.", "The feedback process is best used to maintain posture and regulate slow movements.", "The influence of this process on dynamic joint stabilization is dependent upon the speed and magnitude of joint perturbations.", "Both feed-forward and feedback mechanisms enhance joint stability if these motor pathways are frequently stimulated by way of proprioceptive or rehabilitative training.", "With repetitive stimuli, these pathways create memory in the joint for future movements.", "[0020] At the joint structural level, individuals who are well-conditioned have better joint motion and position sense than those who are deconditioned.", "The deconditioned persons lack adequate somatosensory awareness to coordinate muscle activity and dynamic joint stability, and may be subject to injury.", "Speed and complexity of movement in activities of daily living rely on rapid integration of sensory information by the feed-forward and feedback mechanisms.", "Without sufficient preliminary activity, or training, structures of the joint and extremity may become vulnerable to damage.", "An injury, mechanical or disease-related, causes partial deafferentation (decreased sensory input) of the joint.", "Deafferentation is a decreased afferent neural signal, and is described as a proprioceptive deficit.", "Decreased proprioceptive signals inhibit normal motor response and balance reactions and decrease neuromuscular stabilizations of the joint, which may lead to injury or further damage of joint structures.", "[0021] The purpose of neuromuscular rehabilitation for proprioceptive deficits is to incorporate peripheral sensory input relative to joint position, and to process these signals into efferent motor responses.", "Once proprioceptive deficits have been identified, they need to be corrected in order to prevent episodes of functional instability and repetitive injury.", "Rehabilitation for these deficits should encourage preparatory agonist (contracting) and antagonist (opposing) muscle activity.", "Effective co-activation restores the force couples required to balance joint forces and increases congruency, thus reducing loads on joint structures.", "In a controlled rehabilitation exercise, the placement of joints in vulnerable, or unstable, positions helps re-establish proprioception and appropriate motor responses.", "These stabilizing responses of muscles require sensory anticipation of joint displacement and joint loads.", "Therefore, neuromuscular and balance training focus upon stimulating the sensory pathways from joint structures to the central nervous system.", "Frequent or repetitive use of these pathways has been shown to decrease response time and develop reaction strategies for unexpected events.", "Reflex-mediated muscle activity is a crucial element of the functionally stable joint and should complement pre-programmed activity.", "Proprioceptive rehabilitation should focus upon neuromuscular training by stimulating the reflex pathways from joint structures (ligaments, tendons, cartilage, capsule, epidermis) and surrounding muscles that act as static and dynamic stabilizers.", "Therefore, proprioceptive and balance exercises should provoke joint perturbations (alterations of position) to facilitate reflex muscle activation and postural control.", "By creating postural and/or dynamic imbalance, these rehabilitation activities encourage automatic and appropriate neuromuscular responses.", "Thus, these types of exercise should be initiated early in all rehabilitation programs.", "Patient involvement, by way of home exercises and exercise tools, is also critical to the success of the rehabilitation program.", "[0022] It is important, finally, to mention the role of proprioceptive and balance training in post-surgical or post-injury tissue healing.", "Research has indicated that joint structures increase in strength linear to stresses put upon them (Wolfe's Law) and, also, that there is a strong relationship between joint injury and subsequent loss of motor control.", "It is essential, then, to stress these structures in a functional manner during rehabilitation to promote the proper orientation of joint tissue fibers during healing.", "Selective proprioceptive exercises which simulate realistic tasks can encourage healing of tissues in the same orientation of functional stresses applied to the joints with everyday activities.", "Thus, proprioceptive training provides a protective mechanism against re-injury with return to activity.", "[0023] The present invention comprises materials, or tools, used to elicit joint perturbations and therefore promote reflective neuromuscular training.", "The dense, irregular foam rubber and rock-like shape of the device provides a means of stressing or compressing different soft tissues of the foot, or any other extremity, placed upon them.", "Depending upon the position of the extremity of the device's surface, muscle activation occurs through proprioceptive information to the central nervous system and muscular response to maintain joint stability near stressed structures.", "At the same time, reciprocal inhibition (relaxation of antagonist muscle) occurs in the muscle groups not stressed.", "(i.e. quadriceps contract, hamstrings relax) This co-activation of muscle groups helps to balance the forces surrounding the joint, and, as research has shown, plays a key role in prevention of injury to susceptible tissues (i.e. a knee after ligament surgery).", "Lastly, the forces applied to the distal (furthest end from the torso) extremity by way of the device also provides neuromuscular training for more proximal (closest end to the torso) structures.", "Activity from these proximal structures is required to maintain overall balance and postural stability.", "Therefore, forces from the device applied to the foot, or hand, can provide neuromuscular training for the ankle, knee, and hip, or the forearm, elbow, and shoulder.", "Many studies have documented that the body does not function as a rigid segment, but as a multi-link structure;", "events surrounding the distal segment of an extremity affect those located more proximally in the kinetic chain.", "Thus, the use of the incongruent surface of the device is a crucial element in retraining the sensory pathways to the central nervous system from multiple anatomical structures, so that this information may be stored and retrieved at the appropriate time in the future (with return to activity or sport).", "The various sizes and points of application of the device provides a multitude of opportunities for this type of physical rehabilitation.", "Finally, the fact that the device is both affordable and easily transported make it an ideal home exercise tool, which could complement virtually any neuromuscular or orthopaedic training program.", "[0024] Referring now to FIG. 1 , there is shown a device, generally indicated at 10 , which embodies the present invention.", "Device 10 contains a planar lower surface 12 for positioning device 10 on a flat horizontal surface such as the floor or an exercise mat.", "Upper region 14 of device 10 comprises an irregular incongruent surface.", "Device 10 is preferably constructed from a dense foam rubber which moderately compresses when subjected to the weight of a user.", "The incongruent surface may contain certain surface features, such as a concave or convex section, in areas of the surface to enhance proprioception training for specific areas of the body.", "[0025] FIG. 3 shows device 10 in use, with the foot 20 of a user standing on device 10 .", "Note that the irregular surface 14 allows some compression of device 10 , causing various points of application to the bones, muscles and tendons of the user's foot.", "When the user balances on one foot on device 10 , the brain sends messages to various muscles of the body, instructing them to correct the instability.", "In this manner, proprioceptive deficits can be rehabilitated.", "If the user looks from side to side while balanced, additional proprioceptive information will be sent to the central nervous system, and reaction to this stimulus creates additional rehabilitative effects.", "[0026] FIG. 2 displays an alternative device 10 ′, which exhibits a different upper region 14 ′ that is shown in FIG. 1 .", "The overall size of device 10 ′ may be smaller than device 10 , and is preferably constructed of a denser foam rubber which has less compressibility.", "Device 10 ′ does have a planar lower surface 12 , such that it can be positioned solidly on the floor.", "When a user's foot 12 is placed upon device 10 ′ and the body is balanced on foot 12 , different sensory stimulation is accomplished, as the firmness and orientation of device 10 ′, in addition to its non-uniformity of its outer top surface, are different than that of device 10 .", "[0027] FIG. 4 shows the device of FIG. 3 in use, where the user locates device 10 ′ in the mid-foot area.", "By using the device under different sections of the foot, such as rear foot, mid-foot, and forefoot, other areas of the body including the ankle, knee, and hip structures may be stressed.", "[0028] In addition to stretching the muscles of the foot, which is desirable in sports such as running, proprioceptive balance is promoted not only in the foot, but also in the ankle, knee and hip joint.", "[0029] This preloading of the soft tissues of the foot and ankle prior to exercising helps to prevent injury to these areas.", "[0030] One goal of proprioceptive/balance training is to return patients to their maximum prior level of function.", "Therefore, systems can be designed containing multiple proprioceptive and a balance related challenges specifically to promote reflective neuromuscular training for any individual.", "Such a system is shown in FIG. 5 .", "Referring now to FIG. 5 , a training system designated at 30 consists of a plurality of interchangeable interlocking mats of pads 32 which can be assembled to maximize the rehabilitative regimen of each patient.", "In the center of each pad is a version 10 a - f of the device shown in FIGS. 1 and 3 .", "System 30 contains a mix of multiple proprioceptive and balance related challenges.", "Each pad 32 differs in degree of proprioceptive/balance difficulty on its surface.", "For example, 10 a and 10 d devices may contain a mild degree of difficulty, 10 b and 10 e devices contain a moderate degree of difficulty, and 10 c and 10 f devices contain a severe degree of difficulty.", "Each device may contain an indicia which denotes the degree of difficulty, such as red for simple, blue for difficult, etc.", "In this manner, clinicians can construct a course using different segments, depending on the patient's needs.", "In addition, other compliant surfaces, such as a grasslike surface, or obstacle to step over and around can be inserted into the system to elicit certain neuromuscular responses to suit the patient's needs.", "System 30 can be used to simulate the everchanging proprioceptive and balance changes in the environment which patients face every day during the activities of daily living.", "[0031] While this invention has been shown and described in terms of a preferred embodiment, it will be understood that this invention is not limited to this particular embodiment, and that many changes and modifications may be made without departing from the true spirit and scope of the invention as defined in the appended claims." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a bicycle deraileur of the type which comprises a parallelogrammic linkage mechanism and a chain guide mechanism supported thereby, wherein the linkage mechanism is forcibly deformed against the restoring force of a return spring by a control cable to laterally displace the chain guide mechanism for shifting one sprocket to another diametrically different sprocket. More particularly, the invention relates to such a deraileur which is capable of pre-loading or pre-torsioning the return spring even if the chain guide mechanism is locked in its lateral movement. 2. Description of the Prior Art As is well known, a typical bicycle deraileur comprises a parallelogrammic linkage mechanism mounted to a suitable portion of a bicycle frame and a chain guide mechanism supported by the linkage mechanism. More specifically, the linkage mechanism includes a base member fixed to the bicycle frame, a pair of parallel links each pivotally pinned at one end to the base member, and a movable member pivotally pinned to the other end of each link. In the case of a rear deraileur, the chain guide mechanism is located adjacent to a multiple freewheel and comprises a spring-biased shift frame pivotally mounted to the movable member of the linkage mechanism and supporting a pair of pulleys for engagement with a chain. In the case of a front deraileur, on the other hand, the chain guide mechanism is positioned adjacent to a multiple chainwheel and comprises a pair of guide plates arranged on both sides of the chain as fixed on the movable member of the linkage mechanism. The linkage mechanism is usually biased toward its normal position by a return spring. Typically, such spring is mounted on a pin connecting two adjacent parts (e.g. the base member and one of the links) of the linkage mechanism and has both ends engaging with these two parts. The linkage mechanism is pivotally deformable by a control cable extending from a remote speed change lever for connection to one of the links. Thus, when the speed change lever is operated in one direction, the linkage mechanism is pivotally deformed against the elastic force of the return spring to displace the guide mechanism laterally of the freewheel (rear deraileur) or the chainwheel, thereby shifting the chain from one sprocket to another diametrically different sprocket. When the speed change lever is operated in the reverse direction, the torsioned return spring functions to bring the linkage mechanism toward its original position. In the above prior art deraileur, the return spring is torsioned as much as the linkage mechanism is pivotally deformed. More specifically, if the two adjacent parts of the linkage mechanism engaging with the spring ends are pivoted by an angle of 45° for example relative to each other upon pivotal deformation of the linkage mechanism, the return spring is also torsioned by an angle of 45°. In other words, the elastic restoring force of the return spring increases in proportion to pivotal angle of the linkage mechanism, causing a large difference in restoring force of the spring between the normal position of the linkage mechanism and the maximally deformed position thereof. Such largely increasing returning force of the spring results in deteriorated operability of the speed change lever because the lever must be imparted a sufficient friction which resists a maximally increased returning force of the spring to prevent spontaneous pivotal movement of the lever. It is conceivable to increase the number of helixes of the return spring for the purpose of reducing the variation in restoring force per unit pivotal deformation of the parallelogrammic linkage mechanism. However, such an attempt renders the spring very bulky, which causes troubles in assembly of the deraileur or otherwise requires enlargement of the deraileur with attendant weight increase. Further, with the prior art deraileur, the control cable is connected directly to one of the links, so that the speed change lever is not operable independently of the linkage mechanism. This means that when the bicycle is not running, the chain engaging with or locked on one sprocket prevents the chain guide mechanism or the movable member of the linkage mechanism from moving laterally. Thus, it is impossible in such a locked state to operate the speed change lever. Japanese Patent Publication No. 53-11742 (Published: Apr. 24, 1987; Application No.: 49-143965; Filed: Dec. 12, 1974; Applicant: Shimano Industrial Co., Ltd.; Inventor: Mitsuhide ISOBE) discloses a bicycle rear deraileur which is capable of pre-loading a spring-biased parallelogrammic linkage mechanism. More particularly, the linkage mechanism is provided with an operating member which is pivotally mounted on a pin which connects a base member to a first one of two parallel links. The operating member is always urged by a return spring in a pivotal direction to engage with the first link which in turn is urged by a weaker counteracting spring in an opposite pivotal direction. The operating member is connected to a control cable which, when tensioned by a remote speed change lever, causes the operating member to pivot away from the first link against the restoring force of the first spring. With the deraileur of the above publication, when the speed change lever is operated to tension the control cable, the operating member starts moving away from the first link which, however, follows the operating member under the action of the counteracting spring, thereby pivotally deforming the linkage mechanism as a whole for speed change shifting. When the control cable is freed from tension, on the other hand, the restoring force of the return spring overcomes the elastic force of the weaker counteracting spring to bring the operating member and the first link to their respective original positions. If the parallelogrammic linkage mechanism is locked for example due to non-running of the bicycle, the operating member alone can be pivoted by tensioning the control cable by means of the speed change lever. Such pre-pivoting of the operating member, i.e., pre-loading of the return spring, puts the locked linkage mechanism in a standby condition for shifting since the first link is always under the action of the counteracting spring. Thus, upon start of the bicycle, the linkage mechanism will be immediately deformed by the elastic force of the counteracting spring. The deraileur of the Japanese publication, however, has a disadvantage of requiring two separate springs which complicates the overall structure and necessitates exact balancing the two springs. SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a bicycle deraileur incorporating a parallelogrammic linkage mechanism in which a single spring can provide a returning force as well as a pre-loading function. Another object of the invention is to minimize variation in restoring force of the return spring despite large pivotal deformation of the linkage mechanism. According to the present invention, there is provided a bicycle deraileur comprising: a parallelogrammic linkage mechanism including a base member, a pair of parallel links each pivotally connected at one end thereof to the base member by means of a pin, and a movable member pivotally connected to the other end of each link by means of a pin; a chain guide mechanism carried by the movable member; an operating member mounted on the linkage mechanism and operable by a cable to pivot about an axis parallel to the pins; a torsion spring arranged to engage with the operating member and one of the links, the spring elastically urging the operating member to counteract a tension applied to the cable; and restraining means connecting between a first connecting point on the operating member and a second connecting point on the linkage mechanism to convert pivotal movement of the operating member into smaller pivotal movement of the links, the restraining means allowing the first and second connecting points to move toward each other to torsion the spring. Other objects, features and advantages of the invention will become apparent from the following description of a preferred embodiment given with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: FIG. 1 is a side elevation illustrating a rear deraileur embodying the invention; FIG. 2 shows the same deraileur as viewed in the direction of arrows II--II in FIG. 1; FIG. 3 shows a principal portion of the deraileur as viewed in the direction of arrows III--III in FIG. 2; FIG. 4 is a view similar to FIG. 2 but showing the deraileur with its parallelogrammic linkage mechanism deformed for shifting; FIG. 5 is also a view similar to FIG. 2 but showing the deraileur in a pre-loaded condition; and FIG. 6 is a diagrammatic illustration showing the function of a restraining link. DETAILED DESCRIPTION The drawings illustrate a bicycle rear deraileur for selectively shifting a chain from one sprocket to another of a multiple freewheel. However, the invention is also applicable to a front deraileur which is operated to shift a chain from one sprocket to another of a multiple chainwheel. Referring now to FIG. 1, the rear deraileur 1 of the illustrated embodiment is particularly designed for mounting to a bicycle of the type which has a bicycle stand 2. Such a type of bicycle is mainly manufactured for general use or for ladies. The deraileur 1 comprises a base member 3 having an upper end portion 3a clamped to a rear fork end 4 together with a stand fitting 6 (see also FIG. 2) as supported on a hub shaft 5 which also support a multiple freewheel F. The base member 3 extends forward at its upper end portion to clear the stand 2 and then downward to provide a lower support portion 3b. As better illustrated in FIG. 2, a pair of laterally spaced parallel links 7, 8 are pivotally connected at their respective lower ends to the lower support portion 3b of the base member 3 by means of pins 12, 13, respectively. The respective upper ends of the links 7, 8 are in turn pivotally connected to a movable member 9 by means of pins 14, 15. The four pins 12-15 are positioned at the four corners of a parallelogram. Thus, the base member 3 (more accurately the lower support portion 3b thereof), the two links 7, 8, and the movable member 9 constitute a well known parallelogrammic linkage mechanism 10. The arrangement of the linkage mechanism 10 is such that the movable member 9 translate laterally toward and away from the multiple freewheel F in response to deformation of the linkage mechanism 10. To distinguish between the two links 7, 8 in the following description, the link 7 is referred to as "first link", while the other link 8 is referred to as "second link". The deraileur 1 further comprises a chain guide mechanism 11 mounted to the linkage mechanism 10. More specifically, the guide mechanism 11 includes a downwardly extending shift frame 18 which is pivotally mounted at an upper portion thereof to the movable member 9 of the linkage mechanism 10. The shift frame 18 is provided at its upper end with a guide pulley 16 and at its lower end with a tension pulley 17. The shift frame 18 is always urged by an unillustrated spring so that the lower end of the frame 18 supporting the tension pulley 17 is forcibly moved rewardly. A chain C is guided around a rear half of the tension pulley 17 and then around a front half of the guide pulley 16 to engage with one of sprockets s1-s3 of the freewheel F, the chain C further extending forwardly toward a chainwheel (not shown). Since the shift frame 18 is urged as described above, the tension pulley 17 moves reward upon shifting of the chain C from a larger sprocket s3 or s2 to a smaller sprocket s2 or s1 to eliminate sagging of the chain and to keep it under a suitable tension. The structure and arrangement described above are known and do not feature the present invention. The features of the invention resides in the following arrangement of an operating member and a restraining mechanism. The operating member represented by reference numeral 20 is pivotally supported on the pin 12 which connects the first link 7 to the lower end portion 3b of the base member 3. The operating member 20 has an upwardly extending arm portion 20a, a downwardly extending connecting portion 20b, and an intermediate arcuate guide portion 20c substantially centered about the pin 12. The operating member 20 is operated by a remote speed change lever (not shown) through a double type control cable W. More specifically, the control cable W consist of an outer cable w1 having one end connected to an intermediate portion of the base member 3 by means of an adjustable screw 21, and an inner cable w2 having one end guided along the arcuate guide portion 20c of the operating member 20 to be connected to the connecting portion 20b thereof by means of a clamping member 22. Thus, the operating member 20 is pivotable in response to a pull on the inner cable w1. Further provided on the pin 12 is a torsion spring 23. One end 23a of the spring 23 engages with a stopper projection 24 formed on the first link 7, whereas the other end 23b of the spring engages with a similar stopper projection 25 formed on the operating member 20. In the normal position illustrated in FIG. 2, the spring 23 is kept under a predetermined torsion so that the first link 7 is pivotally biased in a direction of an arrow L relative to the operating member 20 which in turn is pivotally urged in a direction of an arrow q relative to the first link 7. The restraining mechanism according to the illustrated example is provided in the form of a restraining link 26 which connects a predetermined point A on the operating member 20 to another predetermined point B on the parallelogrammic linkage mechanism 10. In the illustrated example, the connecting point A is provided by a pin 27 mounted on the arm portion 20a of the operating member 20, whereas the connecting point B is provided by the pin 15 which pivotally connects the second link 8 of the linkage mechanism 10 to the movable member 9. One end of the restraining link 26 is pivotally connected to the pin 15 (B). The restraining link 26 is formed with an elongated slot 28 which extends from the other end thereof toward the pin 15 and movably receives the pin 27 on the operating member 20. Thus, the restraining link 26 limits the maximum distance between the two pins 27, 15 (points A, B) but allows them to move toward each other. The purpose of the restraining link 26 will be fully described below with reference to FIGS. 5 and 6. In operation, the inner cable W2 of the double control cable W is pulled up by the unillustrated remote speed change lever relative to the outer cable w1 to pivot the operating member 20 in a direction of an arrow p in FIG. 2. Since the lower spring end 23b is arrested by the stopper projection 25 of the operating member 20, such pivotal movement of the operating member 20 causes the spring 23 to rotate in the same direction on the pin 12. Thus, the upper spring end 23a engaging with the stopper projection 24 on the first link 7 causes the parallelogrammic linkage mechanism 10 to pivotally deform in the arrow L direction, so that the shift frame 18 supported by the linkage mechanism 10 translates axially inwardly of the hub shaft 5 to shift the chain C (FIG. 1) from a smaller sprocket s1 or s2 (e.g. the smallest sprocket s1 in FIG. 2) to a larger sprocket s2 or s3 (e.g. the largest sprocket s3), as illustrated in FIG. 4. During the above operation, the restraining link 26 functions in the following manner. In FIG. 6, a smaller circle represents the locus of pivotal movement of the pin 27 or connecting point A on the operating member 20 or arm portion 20a thereof, whereas a larger circle indicates the locus of pivotal movement of the pin 15 or connecting point B on the second link 8. The two pins 27, 15 are connected by the restraining link 26 whose length is invariable. Supposing now that the arm portion 20a pivots through an angle of 30° for example, the pin 27 displaces to a point A1 on the smaller circle, whereas the pin 15 shifts to a point B1 on the larger circle. The distance between the two points A1, B1 is equal to that between the two points A, B since the length of the restraining link 26 is invariable. Similarly, if the arm portion 20a pivots through an additional angle of 30° or 60° for example, the pins 27, 15 moves respectively to different points A2, B2 or A3, B3 on the respective smaller and larger circles, the distance between the two points A2, B2 or A3, B3 being again equal to that between the initial two points A, B. As apparently appreciated in FIG. 6, pivotal movement in any degree of the operating member 20 corresponds to a smaller degree of pivotal movement of the second link 8 (e.g. 90° for the operating member 20 vs. about 45° for the second link 8). In other words, the restraining link 26 serves to limit pivotal movement of the second link 8 to a degree smaller than expected from larger pivotal movement of the operating member 20 which is operatively connected to the parallelogrammic linkage mechanism 10 via the torsion spring 23a. The first link 7 makes the same pivotal movement as the second link 8 because they form two opposite sides of the parallelogrammic linkage mechanism 10. As previously described, the upper end 23a of the spring 23 engages with the stopper projection 24 of the first link 7, while the lower spring end 23b engages with the stopper projection 25 of the operating member 20. Thus, upon pivotal movement of the operating member 20, the spring 23 is torsioned to store a restoring force since the first link 7 is pivoted to a smaller degree than the operating member 20, as explained with reference to FIG. 6. The degree of torsioning of the spring 23 is determined by the difference in pivotal angle between the operating member 20 and the first link 7. The difference in pivotal angle between the operating member 20 and the first link 7 (or the second link 8) is in turn determined firstly by the respective lengths of the restraining link 26, the second link 8 and the operating member arm portion 20a, and secondly by the positional relation between the pins 12, 13. For comparison, it is now assumed that the spring end 20a is caught by the lower support portion 3b of the base member 3 but not by the stopper projection 24 of the first link 7, that the restraining link 26 is omitted, and that the operating member 20 is co-pivotable with the first link 7. In the thus hypothetically modified deraileur, which resembles a typical conventional deraileur in operating principle, the spring 23 is torsioned as much as the operating member 20 is pivoted. According to the present invention, both the first link 7 arresting the upper spring end 20a and the operating member arresting the lower spring end 23b pivot in the same direction but to different degrees due to the limiting function of the restraining link 26. Therefore, the spring 23 is torsioned much more moderately than in the above comparative arrangement. This means that a weaker pull on the inner cable w2 of the double control cable W can displace the shift frame 11 axially inwardly of the hub shaft 5 to conduct a shift-up gear change. When the inner cable w2 is freed from a pull, the operating member 20 is pivoted in the arrow q direction by the restoring force of the previously energized spring 23 to thereby bring the parallelogrammic linkage mechanism 10 to the original position shown in FIG. 2. As a result, the shift frame 18 carried by the linkage mechanism 10 is displaced axially outwardly of the hub shaft 5 to shift the chain C (FIG. 1) from a larger sprocket s3, s2 (largest sprocket s3 in FIG. 4) to a smaller sprocket s2, s1 (smallest sprocket s1 in FIG. 2). If the bicycle is not running and the chain C (FIG. 1) is engaged for example on the smallest sprocket s1 of the non-rotating freewheel F, that particular sprocket s1 prevents the chain C or the chain guide mechanism 11 from moving axially of the hub shaft 5. Even in such an event, the inner cable W2 of the double control cable W can be pulled up to pivot the operating member 20 in the arrow p direction. However, since the parallelogrammic linkage mechanism 10 (chain guide mechanism 11) is prevented from lateral movement, such pivotal movement of the operating member 20 causes the pin 27 to slide within the elongated slot 28 of the restraining link 26 toward the pin 15, as illustrated in FIG. 5. In other words, the lower spring end 23b is pivoted by the operating member 20 in the arrow p direction relative to the non-pivotable upper spring end 23a to torsion the spring 23. Thus, immediately upon running of the bicycle, the linkage mechanism 10 is pivotally deformed by the restoring force of the previously torsioned spring 23 to shift the chain guide mechanism 11 axially inwardly of the hub shaft 5, consequently conducting a shift-up gear change. According to the present invention, the single spring 23 can provide a restoring force as well as a pre-loading or pre-torsioning function for the parallelogrammic linkage mechanism 10. Further, the restoring force does not increase unacceptably despite large pivotal deformation of the linkage mechanism 10, thereby ensuring readier speed change operation. According to the illustrated embodiment, the spring 23 functions to bring the chain guide mechanism 11 to a position immediately under the smallest sprocket s1. Such deraileur is called "top-normal type". However, the spring 23 may be arranged on the pin 12 in a manner such that it always urges the operating member 20 in the arrow p direction to bring the chain guide mechanism 11 to a position immediately under the largest sprocket. The thus modified deraileur is called "low-normal type". Further, the operating member 20 may be reversed in orientation and pivotally supported on the pin 13 which pivotally connects the second link 8 to the lower support portion 3b of the base member 3. In this case, the spring 23 is mounted on the pin 13 and engages with the operating member 20 as well as with the second link 8 to urge the operating member 20 in the arrow p pivotal direction, while the restraining link 26 extends from the pin 27 of the operating member 20 to be pivotally connected to the pin 14 which pivotally connects the second link 7 to the movable member 9. Such a modification also provides a low-normal type deraileur. Still further, the operating member 20 may be arranged on the movable member 9 with suitable rearrangement of the torsion spring 23 and the restraining link 26. The invention being thus described, it is obvious that the same may be varied in many other ways. For instance, the restrained link 26 may be replaced by a wire or cam means which limits the maximum distance between the two points A, B but allows these to come closer to each other. Further, the connecting point B for the restraining link 26 may not be provided by the pin 15 but by another pin located at a suitable position on the movable member 9 or the second link 8. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to those skilled in the art are intended to be included within the scope of the following claims.
A bicycle deraileur comprising a parallelogrammic linkage mechanism including a base member, a first link pivotally connected at one end thereof to the base member by a first pin, a second link pivotally connected at one end thereof to the base member by a second pin, and a movable member pivotally connected to the other ends of the first and second links by third and fourth pins respectively; a chain guide mechanism carried by the movable member; an operating member pivotally mounted on the firs pin for operation by a cable and provided with a pin; a torsion spring arranged on the first pin to engage with the operating member and the first link, the spring elastically urging the operating member to counteract a tension applied to the cable; and a restraining link pivotally connected at one end to the fourth pin and having a slot extending from the other end toward the fourth pin and slidably receiving the pin of the operating member.
Condense the core contents of the given document.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This invention relates to a bicycle deraileur of the type which comprises a parallelogrammic linkage mechanism and a chain guide mechanism supported thereby, wherein the linkage mechanism is forcibly deformed against the restoring force of a return spring by a control cable to laterally displace the chain guide mechanism for shifting one sprocket to another diametrically different sprocket.", "More particularly, the invention relates to such a deraileur which is capable of pre-loading or pre-torsioning the return spring even if the chain guide mechanism is locked in its lateral movement.", "Description of the Prior Art As is well known, a typical bicycle deraileur comprises a parallelogrammic linkage mechanism mounted to a suitable portion of a bicycle frame and a chain guide mechanism supported by the linkage mechanism.", "More specifically, the linkage mechanism includes a base member fixed to the bicycle frame, a pair of parallel links each pivotally pinned at one end to the base member, and a movable member pivotally pinned to the other end of each link.", "In the case of a rear deraileur, the chain guide mechanism is located adjacent to a multiple freewheel and comprises a spring-biased shift frame pivotally mounted to the movable member of the linkage mechanism and supporting a pair of pulleys for engagement with a chain.", "In the case of a front deraileur, on the other hand, the chain guide mechanism is positioned adjacent to a multiple chainwheel and comprises a pair of guide plates arranged on both sides of the chain as fixed on the movable member of the linkage mechanism.", "The linkage mechanism is usually biased toward its normal position by a return spring.", "Typically, such spring is mounted on a pin connecting two adjacent parts (e.g. the base member and one of the links) of the linkage mechanism and has both ends engaging with these two parts.", "The linkage mechanism is pivotally deformable by a control cable extending from a remote speed change lever for connection to one of the links.", "Thus, when the speed change lever is operated in one direction, the linkage mechanism is pivotally deformed against the elastic force of the return spring to displace the guide mechanism laterally of the freewheel (rear deraileur) or the chainwheel, thereby shifting the chain from one sprocket to another diametrically different sprocket.", "When the speed change lever is operated in the reverse direction, the torsioned return spring functions to bring the linkage mechanism toward its original position.", "In the above prior art deraileur, the return spring is torsioned as much as the linkage mechanism is pivotally deformed.", "More specifically, if the two adjacent parts of the linkage mechanism engaging with the spring ends are pivoted by an angle of 45° for example relative to each other upon pivotal deformation of the linkage mechanism, the return spring is also torsioned by an angle of 45°.", "In other words, the elastic restoring force of the return spring increases in proportion to pivotal angle of the linkage mechanism, causing a large difference in restoring force of the spring between the normal position of the linkage mechanism and the maximally deformed position thereof.", "Such largely increasing returning force of the spring results in deteriorated operability of the speed change lever because the lever must be imparted a sufficient friction which resists a maximally increased returning force of the spring to prevent spontaneous pivotal movement of the lever.", "It is conceivable to increase the number of helixes of the return spring for the purpose of reducing the variation in restoring force per unit pivotal deformation of the parallelogrammic linkage mechanism.", "However, such an attempt renders the spring very bulky, which causes troubles in assembly of the deraileur or otherwise requires enlargement of the deraileur with attendant weight increase.", "Further, with the prior art deraileur, the control cable is connected directly to one of the links, so that the speed change lever is not operable independently of the linkage mechanism.", "This means that when the bicycle is not running, the chain engaging with or locked on one sprocket prevents the chain guide mechanism or the movable member of the linkage mechanism from moving laterally.", "Thus, it is impossible in such a locked state to operate the speed change lever.", "Japanese Patent Publication No. 53-11742 (Published: Apr. 24, 1987;", "Application No.: 49-143965;", "Filed: Dec. 12, 1974;", "Applicant: Shimano Industrial Co., Ltd.;", "Inventor: Mitsuhide ISOBE) discloses a bicycle rear deraileur which is capable of pre-loading a spring-biased parallelogrammic linkage mechanism.", "More particularly, the linkage mechanism is provided with an operating member which is pivotally mounted on a pin which connects a base member to a first one of two parallel links.", "The operating member is always urged by a return spring in a pivotal direction to engage with the first link which in turn is urged by a weaker counteracting spring in an opposite pivotal direction.", "The operating member is connected to a control cable which, when tensioned by a remote speed change lever, causes the operating member to pivot away from the first link against the restoring force of the first spring.", "With the deraileur of the above publication, when the speed change lever is operated to tension the control cable, the operating member starts moving away from the first link which, however, follows the operating member under the action of the counteracting spring, thereby pivotally deforming the linkage mechanism as a whole for speed change shifting.", "When the control cable is freed from tension, on the other hand, the restoring force of the return spring overcomes the elastic force of the weaker counteracting spring to bring the operating member and the first link to their respective original positions.", "If the parallelogrammic linkage mechanism is locked for example due to non-running of the bicycle, the operating member alone can be pivoted by tensioning the control cable by means of the speed change lever.", "Such pre-pivoting of the operating member, i.e., pre-loading of the return spring, puts the locked linkage mechanism in a standby condition for shifting since the first link is always under the action of the counteracting spring.", "Thus, upon start of the bicycle, the linkage mechanism will be immediately deformed by the elastic force of the counteracting spring.", "The deraileur of the Japanese publication, however, has a disadvantage of requiring two separate springs which complicates the overall structure and necessitates exact balancing the two springs.", "SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a bicycle deraileur incorporating a parallelogrammic linkage mechanism in which a single spring can provide a returning force as well as a pre-loading function.", "Another object of the invention is to minimize variation in restoring force of the return spring despite large pivotal deformation of the linkage mechanism.", "According to the present invention, there is provided a bicycle deraileur comprising: a parallelogrammic linkage mechanism including a base member, a pair of parallel links each pivotally connected at one end thereof to the base member by means of a pin, and a movable member pivotally connected to the other end of each link by means of a pin;", "a chain guide mechanism carried by the movable member;", "an operating member mounted on the linkage mechanism and operable by a cable to pivot about an axis parallel to the pins;", "a torsion spring arranged to engage with the operating member and one of the links, the spring elastically urging the operating member to counteract a tension applied to the cable;", "and restraining means connecting between a first connecting point on the operating member and a second connecting point on the linkage mechanism to convert pivotal movement of the operating member into smaller pivotal movement of the links, the restraining means allowing the first and second connecting points to move toward each other to torsion the spring.", "Other objects, features and advantages of the invention will become apparent from the following description of a preferred embodiment given with reference to the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: FIG. 1 is a side elevation illustrating a rear deraileur embodying the invention;", "FIG. 2 shows the same deraileur as viewed in the direction of arrows II--II in FIG. 1;", "FIG. 3 shows a principal portion of the deraileur as viewed in the direction of arrows III--III in FIG. 2;", "FIG. 4 is a view similar to FIG. 2 but showing the deraileur with its parallelogrammic linkage mechanism deformed for shifting;", "FIG. 5 is also a view similar to FIG. 2 but showing the deraileur in a pre-loaded condition;", "and FIG. 6 is a diagrammatic illustration showing the function of a restraining link.", "DETAILED DESCRIPTION The drawings illustrate a bicycle rear deraileur for selectively shifting a chain from one sprocket to another of a multiple freewheel.", "However, the invention is also applicable to a front deraileur which is operated to shift a chain from one sprocket to another of a multiple chainwheel.", "Referring now to FIG. 1, the rear deraileur 1 of the illustrated embodiment is particularly designed for mounting to a bicycle of the type which has a bicycle stand 2.", "Such a type of bicycle is mainly manufactured for general use or for ladies.", "The deraileur 1 comprises a base member 3 having an upper end portion 3a clamped to a rear fork end 4 together with a stand fitting 6 (see also FIG. 2) as supported on a hub shaft 5 which also support a multiple freewheel F. The base member 3 extends forward at its upper end portion to clear the stand 2 and then downward to provide a lower support portion 3b.", "As better illustrated in FIG. 2, a pair of laterally spaced parallel links 7, 8 are pivotally connected at their respective lower ends to the lower support portion 3b of the base member 3 by means of pins 12, 13, respectively.", "The respective upper ends of the links 7, 8 are in turn pivotally connected to a movable member 9 by means of pins 14, 15.", "The four pins 12-15 are positioned at the four corners of a parallelogram.", "Thus, the base member 3 (more accurately the lower support portion 3b thereof), the two links 7, 8, and the movable member 9 constitute a well known parallelogrammic linkage mechanism 10.", "The arrangement of the linkage mechanism 10 is such that the movable member 9 translate laterally toward and away from the multiple freewheel F in response to deformation of the linkage mechanism 10.", "To distinguish between the two links 7, 8 in the following description, the link 7 is referred to as "first link", while the other link 8 is referred to as "second link".", "The deraileur 1 further comprises a chain guide mechanism 11 mounted to the linkage mechanism 10.", "More specifically, the guide mechanism 11 includes a downwardly extending shift frame 18 which is pivotally mounted at an upper portion thereof to the movable member 9 of the linkage mechanism 10.", "The shift frame 18 is provided at its upper end with a guide pulley 16 and at its lower end with a tension pulley 17.", "The shift frame 18 is always urged by an unillustrated spring so that the lower end of the frame 18 supporting the tension pulley 17 is forcibly moved rewardly.", "A chain C is guided around a rear half of the tension pulley 17 and then around a front half of the guide pulley 16 to engage with one of sprockets s1-s3 of the freewheel F, the chain C further extending forwardly toward a chainwheel (not shown).", "Since the shift frame 18 is urged as described above, the tension pulley 17 moves reward upon shifting of the chain C from a larger sprocket s3 or s2 to a smaller sprocket s2 or s1 to eliminate sagging of the chain and to keep it under a suitable tension.", "The structure and arrangement described above are known and do not feature the present invention.", "The features of the invention resides in the following arrangement of an operating member and a restraining mechanism.", "The operating member represented by reference numeral 20 is pivotally supported on the pin 12 which connects the first link 7 to the lower end portion 3b of the base member 3.", "The operating member 20 has an upwardly extending arm portion 20a, a downwardly extending connecting portion 20b, and an intermediate arcuate guide portion 20c substantially centered about the pin 12.", "The operating member 20 is operated by a remote speed change lever (not shown) through a double type control cable W. More specifically, the control cable W consist of an outer cable w1 having one end connected to an intermediate portion of the base member 3 by means of an adjustable screw 21, and an inner cable w2 having one end guided along the arcuate guide portion 20c of the operating member 20 to be connected to the connecting portion 20b thereof by means of a clamping member 22.", "Thus, the operating member 20 is pivotable in response to a pull on the inner cable w1.", "Further provided on the pin 12 is a torsion spring 23.", "One end 23a of the spring 23 engages with a stopper projection 24 formed on the first link 7, whereas the other end 23b of the spring engages with a similar stopper projection 25 formed on the operating member 20.", "In the normal position illustrated in FIG. 2, the spring 23 is kept under a predetermined torsion so that the first link 7 is pivotally biased in a direction of an arrow L relative to the operating member 20 which in turn is pivotally urged in a direction of an arrow q relative to the first link 7.", "The restraining mechanism according to the illustrated example is provided in the form of a restraining link 26 which connects a predetermined point A on the operating member 20 to another predetermined point B on the parallelogrammic linkage mechanism 10.", "In the illustrated example, the connecting point A is provided by a pin 27 mounted on the arm portion 20a of the operating member 20, whereas the connecting point B is provided by the pin 15 which pivotally connects the second link 8 of the linkage mechanism 10 to the movable member 9.", "One end of the restraining link 26 is pivotally connected to the pin 15 (B).", "The restraining link 26 is formed with an elongated slot 28 which extends from the other end thereof toward the pin 15 and movably receives the pin 27 on the operating member 20.", "Thus, the restraining link 26 limits the maximum distance between the two pins 27, 15 (points A, B) but allows them to move toward each other.", "The purpose of the restraining link 26 will be fully described below with reference to FIGS. 5 and 6.", "In operation, the inner cable W2 of the double control cable W is pulled up by the unillustrated remote speed change lever relative to the outer cable w1 to pivot the operating member 20 in a direction of an arrow p in FIG. 2. Since the lower spring end 23b is arrested by the stopper projection 25 of the operating member 20, such pivotal movement of the operating member 20 causes the spring 23 to rotate in the same direction on the pin 12.", "Thus, the upper spring end 23a engaging with the stopper projection 24 on the first link 7 causes the parallelogrammic linkage mechanism 10 to pivotally deform in the arrow L direction, so that the shift frame 18 supported by the linkage mechanism 10 translates axially inwardly of the hub shaft 5 to shift the chain C (FIG.", "1) from a smaller sprocket s1 or s2 (e.g. the smallest sprocket s1 in FIG. 2) to a larger sprocket s2 or s3 (e.g. the largest sprocket s3), as illustrated in FIG. 4. During the above operation, the restraining link 26 functions in the following manner.", "In FIG. 6, a smaller circle represents the locus of pivotal movement of the pin 27 or connecting point A on the operating member 20 or arm portion 20a thereof, whereas a larger circle indicates the locus of pivotal movement of the pin 15 or connecting point B on the second link 8.", "The two pins 27, 15 are connected by the restraining link 26 whose length is invariable.", "Supposing now that the arm portion 20a pivots through an angle of 30° for example, the pin 27 displaces to a point A1 on the smaller circle, whereas the pin 15 shifts to a point B1 on the larger circle.", "The distance between the two points A1, B1 is equal to that between the two points A, B since the length of the restraining link 26 is invariable.", "Similarly, if the arm portion 20a pivots through an additional angle of 30° or 60° for example, the pins 27, 15 moves respectively to different points A2, B2 or A3, B3 on the respective smaller and larger circles, the distance between the two points A2, B2 or A3, B3 being again equal to that between the initial two points A, B. As apparently appreciated in FIG. 6, pivotal movement in any degree of the operating member 20 corresponds to a smaller degree of pivotal movement of the second link 8 (e.g. 90° for the operating member 20 vs.", "about 45° for the second link 8).", "In other words, the restraining link 26 serves to limit pivotal movement of the second link 8 to a degree smaller than expected from larger pivotal movement of the operating member 20 which is operatively connected to the parallelogrammic linkage mechanism 10 via the torsion spring 23a.", "The first link 7 makes the same pivotal movement as the second link 8 because they form two opposite sides of the parallelogrammic linkage mechanism 10.", "As previously described, the upper end 23a of the spring 23 engages with the stopper projection 24 of the first link 7, while the lower spring end 23b engages with the stopper projection 25 of the operating member 20.", "Thus, upon pivotal movement of the operating member 20, the spring 23 is torsioned to store a restoring force since the first link 7 is pivoted to a smaller degree than the operating member 20, as explained with reference to FIG. 6. The degree of torsioning of the spring 23 is determined by the difference in pivotal angle between the operating member 20 and the first link 7.", "The difference in pivotal angle between the operating member 20 and the first link 7 (or the second link 8) is in turn determined firstly by the respective lengths of the restraining link 26, the second link 8 and the operating member arm portion 20a, and secondly by the positional relation between the pins 12, 13.", "For comparison, it is now assumed that the spring end 20a is caught by the lower support portion 3b of the base member 3 but not by the stopper projection 24 of the first link 7, that the restraining link 26 is omitted, and that the operating member 20 is co-pivotable with the first link 7.", "In the thus hypothetically modified deraileur, which resembles a typical conventional deraileur in operating principle, the spring 23 is torsioned as much as the operating member 20 is pivoted.", "According to the present invention, both the first link 7 arresting the upper spring end 20a and the operating member arresting the lower spring end 23b pivot in the same direction but to different degrees due to the limiting function of the restraining link 26.", "Therefore, the spring 23 is torsioned much more moderately than in the above comparative arrangement.", "This means that a weaker pull on the inner cable w2 of the double control cable W can displace the shift frame 11 axially inwardly of the hub shaft 5 to conduct a shift-up gear change.", "When the inner cable w2 is freed from a pull, the operating member 20 is pivoted in the arrow q direction by the restoring force of the previously energized spring 23 to thereby bring the parallelogrammic linkage mechanism 10 to the original position shown in FIG. 2. As a result, the shift frame 18 carried by the linkage mechanism 10 is displaced axially outwardly of the hub shaft 5 to shift the chain C (FIG.", "1) from a larger sprocket s3, s2 (largest sprocket s3 in FIG. 4) to a smaller sprocket s2, s1 (smallest sprocket s1 in FIG. 2).", "If the bicycle is not running and the chain C (FIG.", "1) is engaged for example on the smallest sprocket s1 of the non-rotating freewheel F, that particular sprocket s1 prevents the chain C or the chain guide mechanism 11 from moving axially of the hub shaft 5.", "Even in such an event, the inner cable W2 of the double control cable W can be pulled up to pivot the operating member 20 in the arrow p direction.", "However, since the parallelogrammic linkage mechanism 10 (chain guide mechanism 11) is prevented from lateral movement, such pivotal movement of the operating member 20 causes the pin 27 to slide within the elongated slot 28 of the restraining link 26 toward the pin 15, as illustrated in FIG. 5. In other words, the lower spring end 23b is pivoted by the operating member 20 in the arrow p direction relative to the non-pivotable upper spring end 23a to torsion the spring 23.", "Thus, immediately upon running of the bicycle, the linkage mechanism 10 is pivotally deformed by the restoring force of the previously torsioned spring 23 to shift the chain guide mechanism 11 axially inwardly of the hub shaft 5, consequently conducting a shift-up gear change.", "According to the present invention, the single spring 23 can provide a restoring force as well as a pre-loading or pre-torsioning function for the parallelogrammic linkage mechanism 10.", "Further, the restoring force does not increase unacceptably despite large pivotal deformation of the linkage mechanism 10, thereby ensuring readier speed change operation.", "According to the illustrated embodiment, the spring 23 functions to bring the chain guide mechanism 11 to a position immediately under the smallest sprocket s1.", "Such deraileur is called "top-normal type".", "However, the spring 23 may be arranged on the pin 12 in a manner such that it always urges the operating member 20 in the arrow p direction to bring the chain guide mechanism 11 to a position immediately under the largest sprocket.", "The thus modified deraileur is called "low-normal type".", "Further, the operating member 20 may be reversed in orientation and pivotally supported on the pin 13 which pivotally connects the second link 8 to the lower support portion 3b of the base member 3.", "In this case, the spring 23 is mounted on the pin 13 and engages with the operating member 20 as well as with the second link 8 to urge the operating member 20 in the arrow p pivotal direction, while the restraining link 26 extends from the pin 27 of the operating member 20 to be pivotally connected to the pin 14 which pivotally connects the second link 7 to the movable member 9.", "Such a modification also provides a low-normal type deraileur.", "Still further, the operating member 20 may be arranged on the movable member 9 with suitable rearrangement of the torsion spring 23 and the restraining link 26.", "The invention being thus described, it is obvious that the same may be varied in many other ways.", "For instance, the restrained link 26 may be replaced by a wire or cam means which limits the maximum distance between the two points A, B but allows these to come closer to each other.", "Further, the connecting point B for the restraining link 26 may not be provided by the pin 15 but by another pin located at a suitable position on the movable member 9 or the second link 8.", "Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to those skilled in the art are intended to be included within the scope of the following claims." ]
CROSS-REFERENCE TO RELATED APPLICATIONS The present Application is based on International Application No. PCT/EP2007/055410, filed on Jun. 1, 2007, which in turn corresponds to French Application No. 06 52011 filed on Jun. 2, 2006, and priority is hereby claimed under 35 USC §119 based on these applications. Each of these applications are hereby incorporated by reference in their entirety into the present application. FIELD OF THE INVENTION The invention relates to a microwave waveguide, to its production process and to its application to a microwave filter, notably a very high-power microwave filter. The invention is applicable more particularly to filters comprising length-adjustable short-circuited transmission lines, called stubs in the art, and used for producing impedances. The invention also relates to a microwave transmit/receive station using the microwave filter applicable notably in the space field. BACKGROUND OF THE INVENTION In certain fields of application, there is a need for microwave filters of very high power. This is the case for example in the space field, where the transmit power must be particularly high and where the filters used must be effective at high power levels in order to provide a maximum transmit power. This is the case for example in direct transmission systems by satellite. The satellite must then be able to transmit with a maximum power. However, the invention is applicable in any other field in which high-power operation is required. When a waveguide is used in a vacuum (for space applications) and in the case of high-power waveguides, it is possible to initiate an electron avalanche, called a multipactor effect, in certain zones of the waveguide. This multipactor effect is caused by a concentration of the electromagnetic field which tears electrons out of the walls of the waveguide. The electrons are then accelerated toward the opposite wall of the waveguide. The impact of these electrons on the latter wall causes in turn electrons to be torn therefrom, and so on. An electron avalanche phenomenon thus occurs, which degrades the electrical performance of the waveguide and may lead to it being destroyed. This phenomenon therefore occurs notably in the space field in which the waveguides operate in a vacuum in the absence of air molecules. The multipactor power level is the maximum power at which a component can be used without initiating the multipactor effect. This threshold power can be calculated between two parallel plates from the following equation: P= (1/VMF 2 )×( V multi 2 /2 Z 0 ) where the multipactor threshold voltage (V multi ) is dependent on the type of equipment used to manufacture the waveguide, but this voltage is always proportional to the product of the frequency multiplied by the critical distance between the plates (f×d); the VMF (voltage magnification factor) is the ratio of the voltage at the point of calculation and the input voltage of the component. This VMF increases with the field concentration between the two plates at the calculation point; and the impedance (Z 0 ) depends on the standard of waveguide used and on the working frequency (normally fixed by the application). To reduce this multipactor effect, it is possible either to move the walls of the waveguide further apart in order to increase the V multi or to reduce the electric field concentration in order to reduce the VMF. Both these solutions pose problems. If moving the walls of the waveguide further apart is envisioned, the operating frequency range is reduced and the device will have difficulties matching the waveguide for all frequencies in the operating range. To reduce the concentration of the electric field at the critical point, it is necessary to modify the topology of the devices, or even, in the case of filters, to change the type of filter. The object of the invention is to solve these problems and to provide a microwave waveguide and microwave filters in which the multipactor power level has been notably increased. SUMMARY OF THE INVENTION The invention therefore relates to a process for the production of a microwave waveguide comprising the following steps: a step of determining the critical zone or zones of the waveguide where an electric field concentration occurs; and a step of producing at least one enlargement of the waveguide in the zone or zones thus determined. This process is applicable to the production of a microwave filter comprising length-adjustable short-circuited transmission lines, such as stubs. This process includes: a step of determining, in the stubs, critical zones where electric field concentrations occur; and a step of producing at least one enlargement of the stubs in the zone or zones thus determined. Advantageously, each enlargement is located at a distance λg/4 from the short-circuit zone of the stub, λg being a guided wavelength lying within the operating wavelength range of the filter. The invention also relates to a microwave filter produced by this process. Each stub takes the form of a Latin cross in which the horizontal arms perpendicular to the axis of the stub correspond to said enlargements. According to one embodiment of the invention, the horizontal arms are of unequal lengths. According to another embodiment of the invention, at least one horizontal arm has sections of different dimensions. The section closest to the axis of the stub is larger than the section or sections further away from the axis of the stub. According to another embodiment, at least one horizontal arm has sections of different dimensions, the section closest to the axis of the stub being smaller than the section or sections further away from the axis of the stub. It is also possible for the end face of each horizontal arm to be inclined to the axis of the stub. According to another embodiment of the invention, it is also possible for the end face of each horizontal arm to have a curved shape. The invention is also applicable to a microwave transmit/receive station using the microwave filter thus described. This station therefore comprises: a first diplexer for horizontally polarized signals and comprising a first receive filter and a first transmit filter as described above; a second diplexer for vertically polarized signals and comprising a second receive filter and a second transmit filter as described above; and a polarization mode splitter/combiner having a first port for the horizontally polarized signals, connected to the first diplexer, a second port for the vertically polarized signals, connected to the second diplexer, and a third port connected to a transmit/receive horn. Still other objects and advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein the preferred embodiments of the invention are shown and described, simply by way of illustration of the best mode contemplated of carrying out the invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious aspects, all without departing from the invention. Accordingly, the drawings and description thereof are to be regarded as illustrative in nature, and not as restrictive. BRIEF DESCRIPTION OF THE DRAWINGS The present invention is illustrated by way of example, and not by limitation, in the figures of the accompanying drawings, wherein elements having the same reference numeral designations represent like elements throughout and wherein: FIG. 1 a , a representation of a waveguide for explaining the subject of the invention; FIG. 1 b , an exemplary embodiment of a waveguide according to the invention; FIG. 2 , an exemplary embodiment of a filter according to the invention; FIG. 3 , a microwave filter comprising stubs with a low multipactor power level which carries the risk of initiating the multipactor effect; FIGS. 4 a and 4 b , exemplary embodiments of a microwave filter having stubs according to the invention; FIGS. 5 a to 5 e , various embodiments of the stubs of a microwave filter; FIGS. 6 a to 6 c and 7 a to 7 c , alternative embodiments of stubs according to the invention; and FIG. 8 , an example of the invention applied to a microwave transmitter/receiver. DETAILED DESCRIPTION FIG. 1 a shows a waveguide g 1 for propagating a microwave. As is known, variations in electromagnetic energy levels can be detected in the waveguide. Variations in energy levels are illustrated in FIG. 1 a . Energy concentrations appear: notably, in the zone z 1 of the waveguide, a maximum c 1 may be the cause of a multipactor effect, as described above. The zone z 1 of the waveguide may then be damaged. To remedy this, the invention therefore provides a way of identifying and locating the zones, such as Z 1 , in which there may be energy concentrations, and of enlarging the waveguide in these zones. FIG. 1 b therefore shows an example of a waveguide according to the invention in which the walls of the waveguide g 1 have an enlargement el 1 . This enlargement is produced in such a way that the energy concentration in the zone z 1 cannot give rise to a multipacter effect. The invention is also applicable to the production of microwave filters. FIG. 2 shows a portion of a filter that includes coupled impedance-matching elements as shunts on the main waveguide and terminating in short circuits. Such elements are called stubs in the art and will therefore be referred to by this term in the rest of the description. It has been found that the stubs of the filters are the site of electromagnetic energy concentrations. To avoid the creation of multipacter effects in the stubs, an enlargement is therefore provided in the energy concentration zones. In a stub, such as st 1 in FIG. 2 , the maximum energy concentration, for a given wavelength λg, occurs at a distance λg/4 from the short-circuit face cc 1 of the stub. The invention therefore provides, at this distance cc 1 , enlargements el 2 and el 3 on the two guiding walls of the stub. The stub therefore takes the form of a Latin cross, the horizontal arms of which are perpendicular to the axis X of the stub sd 1 and form the enlargements el 2 and el 3 . An example of the invention applied to a microwave filter having stubs will now be described with reference to FIGS. 3 , 4 a and 4 b. FIG. 3 shows a filter g 3 of known type, having six stubs st 2 to st 7 . An energy maximum liable to create a multipactor effect is found in the zone z 3 in the stubs st 4 and st 5 . The invention makes it possible to avoid this multipactor effect. To do this, as shown in FIG. 4 a , the stubs st 4 and st 5 have enlargements e 4 and e 5 in the zone z 3 . These enlargements were positioned as described above. However, in certain cases the distance between stubs may not allow these enlargements to be provided in a filter of the type shown in FIG. 3 . The stubs may then be distributed on either side of the main axis of the filter. What is therefore obtained is a configuration as shown in FIG. 4 b . In addition, this configuration provides enlargements f 2 to f 7 on all the stubs st′ 2 to st′ 7 . Since the maximum energy concentration is highest in the stubs st′ 4 and st′ 5 , the enlargements f 4 and f 5 of these stubs will be larger than the enlargements f 3 and f 6 of the stubs st′ 3 and st′ 6 and much larger than the enlargements f 2 and f 7 of the stubs st′ 2 and st′ 7 . The enlargements may take different forms. FIGS. 5 b to 7 c give various examples of these forms. The aim is to avoid creating a multipactor effect in a stub su 1 shown in FIG. 5 a and in which, without enlargement according to the invention, a multipactor effect would be created. FIGS. 5 b and 5 c show stubs su 1 having enlargements eu 1 and eu 2 as described above. The enlargement eu 2 is larger than the enlargement eu 1 and is provided for a higher initial energy concentration in the stub of FIG. 5 c than in the stub of FIG. 5 b. The stub of FIG. 5 d possesses enlargements having different sections. A first enlargement eu 3 is of relatively large size, and this enlargement has a second enlargement eu′ 3 of smaller size. The enlargements eu 4 and eu′ 4 of FIG. 5 e are of the same type as those of FIG. 5 d , but are of smaller dimensions so as to be effective at different energy levels. In these stubs, the enlargements are symmetrical with respect to the axis X of the stubs. FIG. 6 a shows a stub having an enlargement eu 5 , which itself has an enlargement eu′ 5 of larger size. The enlargements are symmetrical with respect to the axis X of the stub and the enlargement eu′ 5 is symmetrical with respect to the axis Y of the enlargement eu 5 . FIG. 6 b shows a stub of the same type as that in FIG. 6 a , but in which the enlargement eu′ 6 is not symmetrical with respect to the axis Y of the enlargement eu 6 . FIG. 6 c shows a stub that has an enlargement e″ 7 on one side of the axis X of the stub and it has, on the other side of the axis X, an enlargement eu 7 which itself has an enlargement eu′ 7 of larger size. Provision is therefore made for producing enlargements that are not symmetrical with respect to the axes X of the stubs. Moreover, provision may be made for the faces of the ends of the enlargements furthest away from the axis X of the stub not to be parallel to the axis X. This is shown in FIGS. 7 a and 7 b by the faces fa 9 and fa 10 , which are inclined to the axis X. There may also be provision for the walls of the enlargements to have curved surfaces, as shown in FIG. 7 b. According to another embodiment shown in FIG. 7 c , the end faces fall of the enlargements eu 11 may be of curved shape. The various enlargement shapes described above, preventing the multipactor effect, were described within the context of an application to stubs of a filter, but they could be applied to any microwave waveguide. By providing stubs as described in the invention, the power level of the filter may be very greatly increased. Moreover, the stubs as described in the invention have a volume larger than a stub without an enlargement, as shown in FIG. 5 a . This increase in volume results in a significant reduction in ohmic losses. It is therefore possible to use this invention to reduce the ohmic losses of a waveguide and more especially in a filter. An example of such a filter applied in a transmit/receive unit on board a satellite will now be described with reference to FIG. 8 . Such a unit must be able to transmit and receive signals at different energy levels. It must transmit at a maximum energy level and it must receive relatively attenuated signals. The unit shown in FIG. 8 has a single, common horn CO for both transmitting and receiving. Diplexer filters DXH and DXV, for horizontal polarization and vertical polarization respectively, are connected to the ports e 1 and e 2 of a polarization mode splitter/combiner OMT, which is connected via its port e 3 to the transmit/receive horn CO. The receive filters FiRxH and FiRxV may be of relatively low operating power. In contrast, the transmit filters FiTxH and FiTxV must be able to operate at high power levels. The transmit filters FiTxH and FiTxV are designed according to the invention to allow high power levels. It is then possible to produce a unit as shown in FIG. 8 with a single horn CO, for both transmitting and receiving. The invention therefore makes it possible to obtain, in a waveguide and more particularly in a filter: a large increase in the power capability, avoiding the multipactor effects; a reduction in ohmic losses; a structure completely compatible with the methods currently used to manufacture filters with “stubs” that guarantee low passive intermodulation products (PIMPs)l; and a potential saving of one antenna on a satellite. It is possible to combine the transmit (Tx) and receive (Rx) functions into a single antenna even if the Tx power levels are high. It will be readily seen by one of ordinary skill in the art that the present invention fulfils all of the objects set forth above. After reading the foregoing specification, one of ordinary skill in the art will be able to affect various changes, substitutions of equivalents and various aspects of the invention as broadly disclosed herein. It is therefore intended that the protection granted hereon be limited only by definition contained in the appended claims and equivalents thereof.
The invention relates to a process for the production of a microwave waveguide having a step of determining the zone or zones of the waveguide where an electric field concentration occurs. A step of produces at least one enlargement of the waveguide in the zone or zones thus determined. The invention also relates to a microwave filter in which the stubs are provided with such enlargement. The invention has application in microwave filters.
Briefly describe the main idea outlined in the provided context.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS The present Application is based on International Application No. PCT/EP2007/055410, filed on Jun. 1, 2007, which in turn corresponds to French Application No. 06 52011 filed on Jun. 2, 2006, and priority is hereby claimed under 35 USC §119 based on these applications.", "Each of these applications are hereby incorporated by reference in their entirety into the present application.", "FIELD OF THE INVENTION The invention relates to a microwave waveguide, to its production process and to its application to a microwave filter, notably a very high-power microwave filter.", "The invention is applicable more particularly to filters comprising length-adjustable short-circuited transmission lines, called stubs in the art, and used for producing impedances.", "The invention also relates to a microwave transmit/receive station using the microwave filter applicable notably in the space field.", "BACKGROUND OF THE INVENTION In certain fields of application, there is a need for microwave filters of very high power.", "This is the case for example in the space field, where the transmit power must be particularly high and where the filters used must be effective at high power levels in order to provide a maximum transmit power.", "This is the case for example in direct transmission systems by satellite.", "The satellite must then be able to transmit with a maximum power.", "However, the invention is applicable in any other field in which high-power operation is required.", "When a waveguide is used in a vacuum (for space applications) and in the case of high-power waveguides, it is possible to initiate an electron avalanche, called a multipactor effect, in certain zones of the waveguide.", "This multipactor effect is caused by a concentration of the electromagnetic field which tears electrons out of the walls of the waveguide.", "The electrons are then accelerated toward the opposite wall of the waveguide.", "The impact of these electrons on the latter wall causes in turn electrons to be torn therefrom, and so on.", "An electron avalanche phenomenon thus occurs, which degrades the electrical performance of the waveguide and may lead to it being destroyed.", "This phenomenon therefore occurs notably in the space field in which the waveguides operate in a vacuum in the absence of air molecules.", "The multipactor power level is the maximum power at which a component can be used without initiating the multipactor effect.", "This threshold power can be calculated between two parallel plates from the following equation: P= (1/VMF 2 )×( V multi 2 /2 Z 0 ) where the multipactor threshold voltage (V multi ) is dependent on the type of equipment used to manufacture the waveguide, but this voltage is always proportional to the product of the frequency multiplied by the critical distance between the plates (f×d);", "the VMF (voltage magnification factor) is the ratio of the voltage at the point of calculation and the input voltage of the component.", "This VMF increases with the field concentration between the two plates at the calculation point;", "and the impedance (Z 0 ) depends on the standard of waveguide used and on the working frequency (normally fixed by the application).", "To reduce this multipactor effect, it is possible either to move the walls of the waveguide further apart in order to increase the V multi or to reduce the electric field concentration in order to reduce the VMF.", "Both these solutions pose problems.", "If moving the walls of the waveguide further apart is envisioned, the operating frequency range is reduced and the device will have difficulties matching the waveguide for all frequencies in the operating range.", "To reduce the concentration of the electric field at the critical point, it is necessary to modify the topology of the devices, or even, in the case of filters, to change the type of filter.", "The object of the invention is to solve these problems and to provide a microwave waveguide and microwave filters in which the multipactor power level has been notably increased.", "SUMMARY OF THE INVENTION The invention therefore relates to a process for the production of a microwave waveguide comprising the following steps: a step of determining the critical zone or zones of the waveguide where an electric field concentration occurs;", "and a step of producing at least one enlargement of the waveguide in the zone or zones thus determined.", "This process is applicable to the production of a microwave filter comprising length-adjustable short-circuited transmission lines, such as stubs.", "This process includes: a step of determining, in the stubs, critical zones where electric field concentrations occur;", "and a step of producing at least one enlargement of the stubs in the zone or zones thus determined.", "Advantageously, each enlargement is located at a distance λg/4 from the short-circuit zone of the stub, λg being a guided wavelength lying within the operating wavelength range of the filter.", "The invention also relates to a microwave filter produced by this process.", "Each stub takes the form of a Latin cross in which the horizontal arms perpendicular to the axis of the stub correspond to said enlargements.", "According to one embodiment of the invention, the horizontal arms are of unequal lengths.", "According to another embodiment of the invention, at least one horizontal arm has sections of different dimensions.", "The section closest to the axis of the stub is larger than the section or sections further away from the axis of the stub.", "According to another embodiment, at least one horizontal arm has sections of different dimensions, the section closest to the axis of the stub being smaller than the section or sections further away from the axis of the stub.", "It is also possible for the end face of each horizontal arm to be inclined to the axis of the stub.", "According to another embodiment of the invention, it is also possible for the end face of each horizontal arm to have a curved shape.", "The invention is also applicable to a microwave transmit/receive station using the microwave filter thus described.", "This station therefore comprises: a first diplexer for horizontally polarized signals and comprising a first receive filter and a first transmit filter as described above;", "a second diplexer for vertically polarized signals and comprising a second receive filter and a second transmit filter as described above;", "and a polarization mode splitter/combiner having a first port for the horizontally polarized signals, connected to the first diplexer, a second port for the vertically polarized signals, connected to the second diplexer, and a third port connected to a transmit/receive horn.", "Still other objects and advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein the preferred embodiments of the invention are shown and described, simply by way of illustration of the best mode contemplated of carrying out the invention.", "As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious aspects, all without departing from the invention.", "Accordingly, the drawings and description thereof are to be regarded as illustrative in nature, and not as restrictive.", "BRIEF DESCRIPTION OF THE DRAWINGS The present invention is illustrated by way of example, and not by limitation, in the figures of the accompanying drawings, wherein elements having the same reference numeral designations represent like elements throughout and wherein: FIG. 1 a , a representation of a waveguide for explaining the subject of the invention;", "FIG. 1 b , an exemplary embodiment of a waveguide according to the invention;", "FIG. 2 , an exemplary embodiment of a filter according to the invention;", "FIG. 3 , a microwave filter comprising stubs with a low multipactor power level which carries the risk of initiating the multipactor effect;", "FIGS. 4 a and 4 b , exemplary embodiments of a microwave filter having stubs according to the invention;", "FIGS. 5 a to 5 e , various embodiments of the stubs of a microwave filter;", "FIGS. 6 a to 6 c and 7 a to 7 c , alternative embodiments of stubs according to the invention;", "and FIG. 8 , an example of the invention applied to a microwave transmitter/receiver.", "DETAILED DESCRIPTION FIG. 1 a shows a waveguide g 1 for propagating a microwave.", "As is known, variations in electromagnetic energy levels can be detected in the waveguide.", "Variations in energy levels are illustrated in FIG. 1 a .", "Energy concentrations appear: notably, in the zone z 1 of the waveguide, a maximum c 1 may be the cause of a multipactor effect, as described above.", "The zone z 1 of the waveguide may then be damaged.", "To remedy this, the invention therefore provides a way of identifying and locating the zones, such as Z 1 , in which there may be energy concentrations, and of enlarging the waveguide in these zones.", "FIG. 1 b therefore shows an example of a waveguide according to the invention in which the walls of the waveguide g 1 have an enlargement el 1 .", "This enlargement is produced in such a way that the energy concentration in the zone z 1 cannot give rise to a multipacter effect.", "The invention is also applicable to the production of microwave filters.", "FIG. 2 shows a portion of a filter that includes coupled impedance-matching elements as shunts on the main waveguide and terminating in short circuits.", "Such elements are called stubs in the art and will therefore be referred to by this term in the rest of the description.", "It has been found that the stubs of the filters are the site of electromagnetic energy concentrations.", "To avoid the creation of multipacter effects in the stubs, an enlargement is therefore provided in the energy concentration zones.", "In a stub, such as st 1 in FIG. 2 , the maximum energy concentration, for a given wavelength λg, occurs at a distance λg/4 from the short-circuit face cc 1 of the stub.", "The invention therefore provides, at this distance cc 1 , enlargements el 2 and el 3 on the two guiding walls of the stub.", "The stub therefore takes the form of a Latin cross, the horizontal arms of which are perpendicular to the axis X of the stub sd 1 and form the enlargements el 2 and el 3 .", "An example of the invention applied to a microwave filter having stubs will now be described with reference to FIGS. 3 , 4 a and 4 b. FIG. 3 shows a filter g 3 of known type, having six stubs st 2 to st 7 .", "An energy maximum liable to create a multipactor effect is found in the zone z 3 in the stubs st 4 and st 5 .", "The invention makes it possible to avoid this multipactor effect.", "To do this, as shown in FIG. 4 a , the stubs st 4 and st 5 have enlargements e 4 and e 5 in the zone z 3 .", "These enlargements were positioned as described above.", "However, in certain cases the distance between stubs may not allow these enlargements to be provided in a filter of the type shown in FIG. 3 .", "The stubs may then be distributed on either side of the main axis of the filter.", "What is therefore obtained is a configuration as shown in FIG. 4 b .", "In addition, this configuration provides enlargements f 2 to f 7 on all the stubs st′ 2 to st′ 7 .", "Since the maximum energy concentration is highest in the stubs st′ 4 and st′ 5 , the enlargements f 4 and f 5 of these stubs will be larger than the enlargements f 3 and f 6 of the stubs st′ 3 and st′ 6 and much larger than the enlargements f 2 and f 7 of the stubs st′ 2 and st′ 7 .", "The enlargements may take different forms.", "FIGS. 5 b to 7 c give various examples of these forms.", "The aim is to avoid creating a multipactor effect in a stub su 1 shown in FIG. 5 a and in which, without enlargement according to the invention, a multipactor effect would be created.", "FIGS. 5 b and 5 c show stubs su 1 having enlargements eu 1 and eu 2 as described above.", "The enlargement eu 2 is larger than the enlargement eu 1 and is provided for a higher initial energy concentration in the stub of FIG. 5 c than in the stub of FIG. 5 b. The stub of FIG. 5 d possesses enlargements having different sections.", "A first enlargement eu 3 is of relatively large size, and this enlargement has a second enlargement eu′ 3 of smaller size.", "The enlargements eu 4 and eu′ 4 of FIG. 5 e are of the same type as those of FIG. 5 d , but are of smaller dimensions so as to be effective at different energy levels.", "In these stubs, the enlargements are symmetrical with respect to the axis X of the stubs.", "FIG. 6 a shows a stub having an enlargement eu 5 , which itself has an enlargement eu′ 5 of larger size.", "The enlargements are symmetrical with respect to the axis X of the stub and the enlargement eu′ 5 is symmetrical with respect to the axis Y of the enlargement eu 5 .", "FIG. 6 b shows a stub of the same type as that in FIG. 6 a , but in which the enlargement eu′ 6 is not symmetrical with respect to the axis Y of the enlargement eu 6 .", "FIG. 6 c shows a stub that has an enlargement e″ 7 on one side of the axis X of the stub and it has, on the other side of the axis X, an enlargement eu 7 which itself has an enlargement eu′ 7 of larger size.", "Provision is therefore made for producing enlargements that are not symmetrical with respect to the axes X of the stubs.", "Moreover, provision may be made for the faces of the ends of the enlargements furthest away from the axis X of the stub not to be parallel to the axis X. This is shown in FIGS. 7 a and 7 b by the faces fa 9 and fa 10 , which are inclined to the axis X. There may also be provision for the walls of the enlargements to have curved surfaces, as shown in FIG. 7 b. According to another embodiment shown in FIG. 7 c , the end faces fall of the enlargements eu 11 may be of curved shape.", "The various enlargement shapes described above, preventing the multipactor effect, were described within the context of an application to stubs of a filter, but they could be applied to any microwave waveguide.", "By providing stubs as described in the invention, the power level of the filter may be very greatly increased.", "Moreover, the stubs as described in the invention have a volume larger than a stub without an enlargement, as shown in FIG. 5 a .", "This increase in volume results in a significant reduction in ohmic losses.", "It is therefore possible to use this invention to reduce the ohmic losses of a waveguide and more especially in a filter.", "An example of such a filter applied in a transmit/receive unit on board a satellite will now be described with reference to FIG. 8 .", "Such a unit must be able to transmit and receive signals at different energy levels.", "It must transmit at a maximum energy level and it must receive relatively attenuated signals.", "The unit shown in FIG. 8 has a single, common horn CO for both transmitting and receiving.", "Diplexer filters DXH and DXV, for horizontal polarization and vertical polarization respectively, are connected to the ports e 1 and e 2 of a polarization mode splitter/combiner OMT, which is connected via its port e 3 to the transmit/receive horn CO.", "The receive filters FiRxH and FiRxV may be of relatively low operating power.", "In contrast, the transmit filters FiTxH and FiTxV must be able to operate at high power levels.", "The transmit filters FiTxH and FiTxV are designed according to the invention to allow high power levels.", "It is then possible to produce a unit as shown in FIG. 8 with a single horn CO, for both transmitting and receiving.", "The invention therefore makes it possible to obtain, in a waveguide and more particularly in a filter: a large increase in the power capability, avoiding the multipactor effects;", "a reduction in ohmic losses;", "a structure completely compatible with the methods currently used to manufacture filters with “stubs”", "that guarantee low passive intermodulation products (PIMPs)l;", "and a potential saving of one antenna on a satellite.", "It is possible to combine the transmit (Tx) and receive (Rx) functions into a single antenna even if the Tx power levels are high.", "It will be readily seen by one of ordinary skill in the art that the present invention fulfils all of the objects set forth above.", "After reading the foregoing specification, one of ordinary skill in the art will be able to affect various changes, substitutions of equivalents and various aspects of the invention as broadly disclosed herein.", "It is therefore intended that the protection granted hereon be limited only by definition contained in the appended claims and equivalents thereof." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to alimentary pastes and, more particularly, to pre-cooked or instant-cooking oriental-type long noodles having multiple layers, or plies, that differ from one another with respect to the amount of protein and/or starch contained therein. 2. Description of the Prior Art Improvements have conventionally been made in the quality of Japanese-type noodles (called "Udon" in Japan) and of buckwheat noodles, etc., by improving the manufacturing processes, developing additives for improving the noodle quality or by attempting to mix animal protein therewith. However, all such improvements relate substantially to noodles of a single layer and involved the following problems, A-E, inherent with such noodles: (A) Improving the properties of materials to be made into noodles and improving the reconstitution properties of the product noodles generally oppose each other. For example, addition of too much protein causes the dough sheets to be hard and readily broken or cut and prevents the noodle product from being smooth or slippery textured; (B) Effects of additives to the noodles to prevent them from excessively swelling with water are limited; (C) Additives are included in, and affect, the whole of the noodles when they should be effective only on the surfaces and, thus, a portion of the additives is extra and uneconomical and adversely affects the taste and texture of the noodle; (D) Animal or vegetable protein added to the noodles may harden them, reduce the surface smoothness or cause a peculiar protein smell which is inherently bad and adversely affects the consumer's appetite; and (E) Noodles containing protein therein will, when fried, be colored brown, thereby reducing their commercial value. Attempts have also been made to produce Japanese-type noodles having a plurality of layers as exemplified by the prior Japanese utility model publications described below. Japanese No. 27-5472 shows a noodle having a longitudinal bore in which egg liquid is enclosed to provide a particular taste and nourishment and, when the egg liquid is hardened as the noodle is boiled, to prevent the noodle from being broken. This is, however, no improvement of the texture of the noodles in view of the foregoing problems, A-E, and the noodles are not suitable for mass production. Japanese No. 50-15013 shows a noodle having an inner layer consisting essentially of buckwheat flour with a small amount of wheat flour and a proper amount of powdered bonito and outer layers consisting essentially of wheat flour with a small amount of powdered bonito to prevent the inner layers, when boiled, from being broken and to flavor the noodle with bonito. Again, there is no improvement with respect to the foregoing problems, A-E. Japanese No. 51-17263 shows a noodle having a pair of layers, one being a buckwheat paste strip and the other being a wheat paste strip called "Udon". Such a noodle includes the taste of both buckwheat and "Udon" while the wheat paste strip reinforces the buckwheat noodle portion. However, there is no improvement with respect to said problems, A-E. It is an object of this invention, therefore, to provide novel, multi-layer noodles which can be economically mass-produced without breaking or cutting and which can be used for raw, steamed, boiled, dried or pre-cooked noodles. Another object of this invention is to provide multi-layer noodles which can be quickly restored or reconstituted with hot water or as boiled upon consumption, the outer layers having a relatively smoother or more slippery texture and the inner layer or layers having a relatively more elastic or rubbery texture, both textures being significant to Japanese or oriental noodles. A further object of the invention is to provide multi-layer noodles, the outer layers of which, being generally rich in starch and poor in protein, will in production prevent the dough sheet from being broken and will shut in the smell of protein in the inner layers, which is generally rich in protein, while the inner layer, being generally poor in starch, will minimize the undesirable excessive swelling of the noodle in hot water upon consumption. SUMMARY OF THE INVENTION The foregoing and other objects are achieved, according to this invention, by the provision of an alimentary paste or noodle comprising, as the basic component thereof, wheat flour and having a plurality of layers; preferably, an inner layer and a pair of outer layers sandwiching the inner layer. The ratio of the amounts of protein to starch contained in the inner layer or layers being substantially greater than that of the outer layers. Mathematically, this is expressed as: BRIEF DESCRIPTION OF THE DRAWINGS Preferred, but not restrictive, embodiments of this invention will be described hereinafter with reference to the accompanying drawings in which: FIG. 1 schematically illustrates a process of making a three-layer paste; FIG. 2 is an enlarged view of the three-layer paste in longitudinal section; and FIG. 3 shows a five-layer paste in longitudinal section. DETAILED DESCRIPTION OF THE INVENTION The alimentary pastes or noodles according to the present invention having the specified ratios of protein and starch can be prepared by the following six methods. In methods (1)-(5) below, it is assumed that both inner and outer layers comprise wheat flour containing the same weight percentages of protein and starch; for example, flour of the same grade or (flour) strength. Methods: (1) Only the inner layer is enriched with protein. The outer layers are unchanged; (2) The inner layer is enriched with protein and the outer layers with starch; (3) The inner layer is enriched with protein more than the outer layers are; (4) Only the outer layers are enriched with starch. The inner layer is unchanged; (5) The outer layers are enriched with starch more than the inner layer is; and (6) The inner layer comprises as material wheat flour originally containing richer protein, while the outer layers comprise as material wheat flour originally containing poorer protein. It is to be noted here that the terminology "inner layer" as employed herein is intended to include a single layer or a plurality of inner layers as exemplified by the embodiment according to the invention illustrated in FIG. 3. The kinds of raw materials to be employed in the present invention may be as described below. The flour used as the principal material of the pastes may have an appropriate flour strength, such as strong, semi-strong, medium or weak flour depending on each embodiment. The starch that is added to the flour according to the invention may be any one or a mixture of starches including cereal starch such as flour starch, rice powder, rice starch and corn starch, etc.; potato starch; sweet potato starch, tapioca, etc. In terms of achieving a smooth texture, potato starch is most preferable empirically. The protein that is added to the flour may be any one or a mixture of proteins, including vegetable protein, such as protein obtained from seed for oil extraction, powdered soybean or soya bean protein, cottonseed, peanut and sesame and the like; cereal flour protein (gluten), yeast protein (powdered yeast extract), algae protein (chlorella powder, spirulina powder); and animal protein such as that from eggs, milk protein (casein), sea products (powdered pollack, etc.), meats and the like. Further additives to the flour which may be used selectively in the various layers include the usual additives, such as sodium chloride, "Kansui" (a kind of natural water available in China and containing one or more of the components: potassium carbonate, sodium bicarbonate, potassium phosphates and sodium phosphates), lecithins, glycerine fatty acid ester, suger ester or emulsified oil as an emulsifier for improving slipperiness or smoothness of the paste and reconstitution in hot water. Wheat germ may be mixed within the inner layer. Referring to the drawings, the alimentary pastes according to this invention are prepared by, firstly, mixing predetermined amounts of flour and other materials (as indicated in the working examples) by mixers 1a-1c, mixers 1a and 1c being used for the outer layers and mixer 1b for the inner layer. In the mixers, the mixtures are kneaded in a conventional manner to form individual doughs. Each dough is passed between a pair of rolls 2a, 2b, 2c to form a dough sheet, or band, A, B and C, each of which is about 0.8-8 millimeters thick (as measured after having slightly expanded following about ten or more seconds after being released from between the rolls). The three sheets are brought together and passed between another pair of rolls 3 and between further pairs of rolls (not shown) with sheet B interposed between sheets A and C to finally form a three-layer paste D (also shown in FIG. 2) which is about 0.5-4 mm thick (as measured after having slightly expanded following about ten seconds or more after being released from the last pair of rolls (not shown). Rolled paste D is cut into strips or strings (not shown) of a suitable width of from about 1 to 4 mm and of a proper length for human consumption. The ratio of thickness of the inner layer to that of each of the outer layers may be in the range of 1:10-10:1 and, preferably, is in the range of 1:4-2:1 in view of producibility, texture and costs. The strips may, depending on the uses, be immediately packed for market, or boiled or steamed at 80°-100° C. for 1-3 minutes, fried at 130°-160° C. for 1-3 minutes or dried in air at 60°-90° C. for 30-50 minutes, all in a conventional manner. Inner layer B is preferably a single ply as shown in FIG. 2, or may consist of three plies B', as shown in FIG. 3, where an inner ply Y has the same composition as outer layers A' and C', while outer plies X and Z of the inner "layer" B' have the same composition as inner layer B of FIG. 2. Working examples of this invention are as follows: EXAMPLE 1 This example illustrates Method (1) described above. The material of the inner layer was a mixture of: 700 grams of semi-strong wheat flour; 300 grams of soybean protein powder; 15 grams of sodium chloride; and 320 grams of water. The material of the outer layers was a mixture of: 1,000 grams of semi-strong wheat flour; 15 grams of sodium chloride; and 310 grams of water. Each mixture was kneaded and rolled into a dough sheet. The ratio of thickness of the inner layer to that of each outer layer sheet was 2:1. The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 0.8 mm thick sheet of paste, which was then cut into 1.5 mm wide strips. The strips were steamed at 100° C. for 2 minutes and fried in 150° C. lard for 3 minutes. For purposes of consumption, the resultant three-layer strips were put in 95° C. water for 3 minutes and became smooth, slippery and elastically/rubbery textured. EXAMPLE 2 This example illustrates Method (2). The material of the inner layer was a mixture of: 750 grams of strong wheat flour (high strength); 150 grams of soybean protein; 50 grams of vital gluten powder; 50 grams of casein; 15 grams of sodium chloride; 5 grams of Kansui water; and 380 grams of water. The material of the outer layers was a mixture of: 800 grams of semi-strong wheat flour; 200 grams of starch; 15 grams of sodium chloride; 3 grams of Kansui water; and 320 grams of water. Each mixture was kneaded and rolled into a dough sheet. The ratio of thickness of the inner layer sheet to that of each outer layer sheet was 4:1. The sheets were then rolled, with the inner layer sheet interposed between the outer layer sheets to form a 1.2 mm thick paste, which was then cut into 1.7 mm wide strips. The strips were steamed at 100° C. for 2 minutes and dried in 85° C. air for 40 minutes. For purposes of consumption, the resultant strips were boiled for 4 minutes and obtained a texture similar to that of Example 1. EXAMPLE 3 This example illustrates Method (3). The material of the inner layer was a mixture of: 750 grams of semi-strong wheat flour; 100 grams of soybean protein; 100 grams of casein; 50 grams of vital gluten powder; 20 grams of sodium chloride; 5 grams of Kansui water; and 370 grams of water. The material of the outer layers was a mixture of: 1,000 grams of medium wheat flour; 30 grams of egg white; 20 grams of sodium chloride; 2 grams of Kansui water; and 320 grams of water. Each mixture was kneaded and rolled into a dough sheet. The ratio of thickness of the inner layer sheet to that of each outer layer sheet was 1:1. The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 1.3 mm thick paste, which was then cut into 1.5 mm wide strips. The strips were steamed at 90°-100° C. for 1 minute. For purposes of consumption, the resultant Chinese noodle type strips were boiled for 5 minutes and became fixedly textured while the boiling water became a little muddied. EXAMPLE 4 This example illustrates Method (4). The material of the inner layer is a mixture of: 1,000 grams of semi-strong wheat flour; 20 grams of sodium chloride; 3 grams of Kansui water; and 320 grams of water. The material of the outer layers is a mixture of: 800 grams of semi-strong wheat flour; 200 grams of starch; 20 grams of sodium chloride; 4 grams of lecithin; 2 grams of Kansui water; and 330 grams of water. Each mixture was kneaded and rolled into a dough sheet. The ratio of thickness of the inner layer sheet to that of each outer layer was 2:1. The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 1.1 mm thick paste, which was then cut into 1.5 mm wide strips. The strips were steamed at 100° C. for 1.5 minutes and fried in palm oil of 135° C. for 1.5 minutes. For purposes of consumption, the fired strips were boiled for 3 minutes and became smooth and elastically textured. EXAMPLE 5 This example illustrates Method (5). The material of the inner layer is a mixture of: 600 grams of semi-strong wheat flour; 200 grams of semolina; 200 grams of potato flour starch; 20 grams of sodium chloride; 1 gram of disodium phosphate; 30 grams of rice oil; and 320 grams of water. The material of the outer layers is a mixture of: 300 grams of semi-strong wheat flour; 200 grams of semolina; 500 grams of potato flour starch; 20 grams of sodium chloride; 1 gram of disodium phosphate; 30 grams of rice oil; and 340 grams of water. Each mixture was kneaded and rolled into a dough sheet. The ratio of thickness of the inner layer sheet to that of each outer layer was 1:1. The sheets were then rolled with the inner layer sheet interposed between the outer layers sheets to form a 2 mm thick paste, which was cut into 2 mm wide strips. The strips were boiled for 4 minutes and cooled. For purposes of consumption, the strips were boiled for 2 minutes and became spagetti-like textured. EXAMPLE 6 This example illustrates Method (6). The material of the inner layer was a mixture of: 1,000 grams of strong wheat flour; 15 grams of sodium chloride; and 350 grams of water. The material of the outer layers was a mixture of: 1,000 grams of weak wheat flour; 15 grams of sodium chloride; and 350 grams of water. Each mixture was kneaded and rolled into a dough sheet. The ratio of thickness of the inner layer sheet to that of each outer layer sheet was 2:1. The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 2 mm thick paste, which was then cut into 2.5 mm wide strips. For purposes of consumption, the Japanese noodle type strips were boiled for 10-15 minutes and became elastically textured and relatively transparent looking. EXAMPLE 7 This example also follows Method (1) for purposes of experimental comparison with a conventional single-layer noodle prepared by the addition to the flour of different amounts of protein. The material of the single-layer noodle and of the inner layer of the three-layer noodle was a mixture of: 1 kilogram (total) of semi-strong wheat flour and vital gluten powder; 16 grams of sodium chloride; 2 grams of Kansui water; and 320 grams of water. The material of the outer layers of the three-layer noodle was a mixture of: 1 kilogram of semi-strong wheat flour; 15 grams of sodium chloride; 2 grams of Kansui water; and 310 grams of water. The mixture for the single-layer noodle was kneaded and rolled into a 1.2 mm thick dough sheet. The mixtures for the three-layer noodle were kneaded and rolled in the same manner as Example 1 to form a 1.2 mm thick dough sheet. Each sheet was cut into 1.5 mm wide strips and steamed at 97°-100° C. for 1 minute and fried in 135° C. palm oil for 1.5 minutes. To prepare the noodles for consumption, the strips were boiled for 3 minutes and gave the results shown in Tables 1 and 2 below. EXAMPLE 8 This example also follows Method (4) for purposes of experimental comparison with a conventional single-layer noodle prepared by the addition to the flour of different amounts of starch. The material of the single-layer noodle and the outer layers of the three-layer noodle was each a mixture of: 1 kilogram (total) of semi-strong wheat flour and potato starch; 20 grams of sodium chloride; 3 grams of Kansui water; and 350 grams of water. The material of the inner layer of the three-layer noodle was a mixture of: 1 kilogram of semi-strong wheat flour; 20 grams of sodium chloride; 3 grams of Kansui water; and 350 grams of water. The mixture for the single-layer noodle was kneaded and rolled into a 0.95 mm thick dough sheet. The mixtures for the three-layer noodle were kneaded and rolled in the same manner as in Example 4 to form a 0.95 mm thick dough sheet. Each sheet was cut into 1.7 mm wide strips and steamed at 97°-100° C. for 2 minutes and dried in 85° C. air for 40 minutes. To prepare the noodles for consumption, the strips were put in 95° C. hot water for 4 minutes to give the results shown in Tables 3 and 4 below: TABLE 1______________________________________Applicant's three-layer noodle (Method (1))Amount in wt. % of vital gluten powder addedto inner layer (1) 5 10 20 40 60 80______________________________________Producibility (2) well well well well well some- what badSmoothness (4) high high high high some- some- what what low lowExpansion with some-Hot Water (3) what low low low low low highRestorability (4) high high high high some- some- what what low lowElasticity (4) some- high high high high some- what what low lowSmell or Odor (4) good good good good good some- what bad______________________________________ TABLE 2__________________________________________________________________________One-Layer noodleAmount in wt. % of vital gluten powderadded to noodle 5 10 20 40 60 80__________________________________________________________________________Producibility well well somewhat bad bad bad badSmoothness high somewhat low low low low badExpansion with HotWater low low low low low lowRestorability high somewhat low low low low lowElasticity somewhat high high somewhat low low low lowSmell or Odor somewhat bad bad bad bad bad bad__________________________________________________________________________ TABLE 3______________________________________Applicants'three-layer noodleAmount in wt. % of starch added to outer layer 5 20 40 60 90______________________________________Producibility well well well well somewhat wellSmoothness some- some- high very very high what what high low lowExpansion with some- little little little littleHot water what greatRestorability low high high high highElasticity some- some- high very very high what what high low low______________________________________ TABLE 4______________________________________One-layer noodleAmount in wt. % of starch added to noodle 5 20 40 60 90______________________________________Producibility well well some- not produ- not pro- what cible when ducible well noodles are thinner than 1.5mmSmoothness low some- high what lowExpansion withHot Water great great littleRestorability low low highElasticity low some- high what low______________________________________ NOTES:- (1) The percentage by weight of the amount of vital glutan powder or starch is based on the total amount of the flour and the gluten powder or starch added thereto; (2) "Producibility" means how well the noodle can be produced without breaks or cuts during rolling or cutting into (3) "Expansion with hot water" was observed 10 minutes after the noodles were restored with the hot water; and (4) "Smoothness", "Restorability", "Elasticity" and "Smell or Odor" were observed immediately after the noodles were restored with the hot water o by boiling as the case may be. As is apparent from Table 1 , the amount of vital glutan powder added to the inner layer may be within the range of 5-80 wt. % (based on the weight of the flour and protein) and should preferably be 10-50 wt. %. An amount of the vital gluten powder of less than 5 wt. % will have no substantial effect, while an amount of more than 80 wt. % produces all undesirable results with respect to all of the aspects of Table 1 except "expansion with hot water." As is apparent from Table 3, the amount of the starch added to the outer layers should be within the range of 5-90 wt. % (based on the weight of flour and starch) and preferably 20-60 wt. %. An amount of the starch of less than 5 wt. % will have no substantial effects while an amount of more than 90 wt. % will cause breaks in the noodles. Although the invention has been described with respect to certain preferred embodiments thereof, it is not intended to be limited thereto but, instead, includes all those embodiments within the scope and spirit of the appended claims.
An alimentary paste having improved texture and production and reconstitution properties. The paste is a wheat flour paste which is in the form of a multi-layer paste, or laminate, of a pair of outer layers having sandwiched therebetween, preferably, a single inner layer. The pastes of the respective layers are prepared such that the ratio of the amount of starch to the amount of protein of each of the outer layers is substantially greater than that of the inner layer.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to alimentary pastes and, more particularly, to pre-cooked or instant-cooking oriental-type long noodles having multiple layers, or plies, that differ from one another with respect to the amount of protein and/or starch contained therein.", "Description of the Prior Art Improvements have conventionally been made in the quality of Japanese-type noodles (called "Udon"", "in Japan) and of buckwheat noodles, etc.", ", by improving the manufacturing processes, developing additives for improving the noodle quality or by attempting to mix animal protein therewith.", "However, all such improvements relate substantially to noodles of a single layer and involved the following problems, A-E, inherent with such noodles: (A) Improving the properties of materials to be made into noodles and improving the reconstitution properties of the product noodles generally oppose each other.", "For example, addition of too much protein causes the dough sheets to be hard and readily broken or cut and prevents the noodle product from being smooth or slippery textured;", "(B) Effects of additives to the noodles to prevent them from excessively swelling with water are limited;", "(C) Additives are included in, and affect, the whole of the noodles when they should be effective only on the surfaces and, thus, a portion of the additives is extra and uneconomical and adversely affects the taste and texture of the noodle;", "(D) Animal or vegetable protein added to the noodles may harden them, reduce the surface smoothness or cause a peculiar protein smell which is inherently bad and adversely affects the consumer's appetite;", "and (E) Noodles containing protein therein will, when fried, be colored brown, thereby reducing their commercial value.", "Attempts have also been made to produce Japanese-type noodles having a plurality of layers as exemplified by the prior Japanese utility model publications described below.", "Japanese No. 27-5472 shows a noodle having a longitudinal bore in which egg liquid is enclosed to provide a particular taste and nourishment and, when the egg liquid is hardened as the noodle is boiled, to prevent the noodle from being broken.", "This is, however, no improvement of the texture of the noodles in view of the foregoing problems, A-E, and the noodles are not suitable for mass production.", "Japanese No. 50-15013 shows a noodle having an inner layer consisting essentially of buckwheat flour with a small amount of wheat flour and a proper amount of powdered bonito and outer layers consisting essentially of wheat flour with a small amount of powdered bonito to prevent the inner layers, when boiled, from being broken and to flavor the noodle with bonito.", "Again, there is no improvement with respect to the foregoing problems, A-E.", "Japanese No. 51-17263 shows a noodle having a pair of layers, one being a buckwheat paste strip and the other being a wheat paste strip called "Udon".", "Such a noodle includes the taste of both buckwheat and "Udon"", "while the wheat paste strip reinforces the buckwheat noodle portion.", "However, there is no improvement with respect to said problems, A-E.", "It is an object of this invention, therefore, to provide novel, multi-layer noodles which can be economically mass-produced without breaking or cutting and which can be used for raw, steamed, boiled, dried or pre-cooked noodles.", "Another object of this invention is to provide multi-layer noodles which can be quickly restored or reconstituted with hot water or as boiled upon consumption, the outer layers having a relatively smoother or more slippery texture and the inner layer or layers having a relatively more elastic or rubbery texture, both textures being significant to Japanese or oriental noodles.", "A further object of the invention is to provide multi-layer noodles, the outer layers of which, being generally rich in starch and poor in protein, will in production prevent the dough sheet from being broken and will shut in the smell of protein in the inner layers, which is generally rich in protein, while the inner layer, being generally poor in starch, will minimize the undesirable excessive swelling of the noodle in hot water upon consumption.", "SUMMARY OF THE INVENTION The foregoing and other objects are achieved, according to this invention, by the provision of an alimentary paste or noodle comprising, as the basic component thereof, wheat flour and having a plurality of layers;", "preferably, an inner layer and a pair of outer layers sandwiching the inner layer.", "The ratio of the amounts of protein to starch contained in the inner layer or layers being substantially greater than that of the outer layers.", "Mathematically, this is expressed as: BRIEF DESCRIPTION OF THE DRAWINGS Preferred, but not restrictive, embodiments of this invention will be described hereinafter with reference to the accompanying drawings in which: FIG. 1 schematically illustrates a process of making a three-layer paste;", "FIG. 2 is an enlarged view of the three-layer paste in longitudinal section;", "and FIG. 3 shows a five-layer paste in longitudinal section.", "DETAILED DESCRIPTION OF THE INVENTION The alimentary pastes or noodles according to the present invention having the specified ratios of protein and starch can be prepared by the following six methods.", "In methods (1)-(5) below, it is assumed that both inner and outer layers comprise wheat flour containing the same weight percentages of protein and starch;", "for example, flour of the same grade or (flour) strength.", "Methods: (1) Only the inner layer is enriched with protein.", "The outer layers are unchanged;", "(2) The inner layer is enriched with protein and the outer layers with starch;", "(3) The inner layer is enriched with protein more than the outer layers are;", "(4) Only the outer layers are enriched with starch.", "The inner layer is unchanged;", "(5) The outer layers are enriched with starch more than the inner layer is;", "and (6) The inner layer comprises as material wheat flour originally containing richer protein, while the outer layers comprise as material wheat flour originally containing poorer protein.", "It is to be noted here that the terminology "inner layer"", "as employed herein is intended to include a single layer or a plurality of inner layers as exemplified by the embodiment according to the invention illustrated in FIG. 3. The kinds of raw materials to be employed in the present invention may be as described below.", "The flour used as the principal material of the pastes may have an appropriate flour strength, such as strong, semi-strong, medium or weak flour depending on each embodiment.", "The starch that is added to the flour according to the invention may be any one or a mixture of starches including cereal starch such as flour starch, rice powder, rice starch and corn starch, etc.", "potato starch;", "sweet potato starch, tapioca, etc.", "In terms of achieving a smooth texture, potato starch is most preferable empirically.", "The protein that is added to the flour may be any one or a mixture of proteins, including vegetable protein, such as protein obtained from seed for oil extraction, powdered soybean or soya bean protein, cottonseed, peanut and sesame and the like;", "cereal flour protein (gluten), yeast protein (powdered yeast extract), algae protein (chlorella powder, spirulina powder);", "and animal protein such as that from eggs, milk protein (casein), sea products (powdered pollack, etc.), meats and the like.", "Further additives to the flour which may be used selectively in the various layers include the usual additives, such as sodium chloride, "Kansui"", "(a kind of natural water available in China and containing one or more of the components: potassium carbonate, sodium bicarbonate, potassium phosphates and sodium phosphates), lecithins, glycerine fatty acid ester, suger ester or emulsified oil as an emulsifier for improving slipperiness or smoothness of the paste and reconstitution in hot water.", "Wheat germ may be mixed within the inner layer.", "Referring to the drawings, the alimentary pastes according to this invention are prepared by, firstly, mixing predetermined amounts of flour and other materials (as indicated in the working examples) by mixers 1a-1c, mixers 1a and 1c being used for the outer layers and mixer 1b for the inner layer.", "In the mixers, the mixtures are kneaded in a conventional manner to form individual doughs.", "Each dough is passed between a pair of rolls 2a, 2b, 2c to form a dough sheet, or band, A, B and C, each of which is about 0.8-8 millimeters thick (as measured after having slightly expanded following about ten or more seconds after being released from between the rolls).", "The three sheets are brought together and passed between another pair of rolls 3 and between further pairs of rolls (not shown) with sheet B interposed between sheets A and C to finally form a three-layer paste D (also shown in FIG. 2) which is about 0.5-4 mm thick (as measured after having slightly expanded following about ten seconds or more after being released from the last pair of rolls (not shown).", "Rolled paste D is cut into strips or strings (not shown) of a suitable width of from about 1 to 4 mm and of a proper length for human consumption.", "The ratio of thickness of the inner layer to that of each of the outer layers may be in the range of 1:10-10:1 and, preferably, is in the range of 1:4-2:1 in view of producibility, texture and costs.", "The strips may, depending on the uses, be immediately packed for market, or boiled or steamed at 80°-100° C. for 1-3 minutes, fried at 130°-160° C. for 1-3 minutes or dried in air at 60°-90° C. for 30-50 minutes, all in a conventional manner.", "Inner layer B is preferably a single ply as shown in FIG. 2, or may consist of three plies B', as shown in FIG. 3, where an inner ply Y has the same composition as outer layers A'", "and C', while outer plies X and Z of the inner "layer"", "B'", "have the same composition as inner layer B of FIG. 2. Working examples of this invention are as follows: EXAMPLE 1 This example illustrates Method (1) described above.", "The material of the inner layer was a mixture of: 700 grams of semi-strong wheat flour;", "300 grams of soybean protein powder;", "15 grams of sodium chloride;", "and 320 grams of water.", "The material of the outer layers was a mixture of: 1,000 grams of semi-strong wheat flour;", "15 grams of sodium chloride;", "and 310 grams of water.", "Each mixture was kneaded and rolled into a dough sheet.", "The ratio of thickness of the inner layer to that of each outer layer sheet was 2:1.", "The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 0.8 mm thick sheet of paste, which was then cut into 1.5 mm wide strips.", "The strips were steamed at 100° C. for 2 minutes and fried in 150° C. lard for 3 minutes.", "For purposes of consumption, the resultant three-layer strips were put in 95° C. water for 3 minutes and became smooth, slippery and elastically/rubbery textured.", "EXAMPLE 2 This example illustrates Method (2).", "The material of the inner layer was a mixture of: 750 grams of strong wheat flour (high strength);", "150 grams of soybean protein;", "50 grams of vital gluten powder;", "50 grams of casein;", "15 grams of sodium chloride;", "5 grams of Kansui water;", "and 380 grams of water.", "The material of the outer layers was a mixture of: 800 grams of semi-strong wheat flour;", "200 grams of starch;", "15 grams of sodium chloride;", "3 grams of Kansui water;", "and 320 grams of water.", "Each mixture was kneaded and rolled into a dough sheet.", "The ratio of thickness of the inner layer sheet to that of each outer layer sheet was 4:1.", "The sheets were then rolled, with the inner layer sheet interposed between the outer layer sheets to form a 1.2 mm thick paste, which was then cut into 1.7 mm wide strips.", "The strips were steamed at 100° C. for 2 minutes and dried in 85° C. air for 40 minutes.", "For purposes of consumption, the resultant strips were boiled for 4 minutes and obtained a texture similar to that of Example 1.", "EXAMPLE 3 This example illustrates Method (3).", "The material of the inner layer was a mixture of: 750 grams of semi-strong wheat flour;", "100 grams of soybean protein;", "100 grams of casein;", "50 grams of vital gluten powder;", "20 grams of sodium chloride;", "5 grams of Kansui water;", "and 370 grams of water.", "The material of the outer layers was a mixture of: 1,000 grams of medium wheat flour;", "30 grams of egg white;", "20 grams of sodium chloride;", "2 grams of Kansui water;", "and 320 grams of water.", "Each mixture was kneaded and rolled into a dough sheet.", "The ratio of thickness of the inner layer sheet to that of each outer layer sheet was 1:1.", "The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 1.3 mm thick paste, which was then cut into 1.5 mm wide strips.", "The strips were steamed at 90°-100° C. for 1 minute.", "For purposes of consumption, the resultant Chinese noodle type strips were boiled for 5 minutes and became fixedly textured while the boiling water became a little muddied.", "EXAMPLE 4 This example illustrates Method (4).", "The material of the inner layer is a mixture of: 1,000 grams of semi-strong wheat flour;", "20 grams of sodium chloride;", "3 grams of Kansui water;", "and 320 grams of water.", "The material of the outer layers is a mixture of: 800 grams of semi-strong wheat flour;", "200 grams of starch;", "20 grams of sodium chloride;", "4 grams of lecithin;", "2 grams of Kansui water;", "and 330 grams of water.", "Each mixture was kneaded and rolled into a dough sheet.", "The ratio of thickness of the inner layer sheet to that of each outer layer was 2:1.", "The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 1.1 mm thick paste, which was then cut into 1.5 mm wide strips.", "The strips were steamed at 100° C. for 1.5 minutes and fried in palm oil of 135° C. for 1.5 minutes.", "For purposes of consumption, the fired strips were boiled for 3 minutes and became smooth and elastically textured.", "EXAMPLE 5 This example illustrates Method (5).", "The material of the inner layer is a mixture of: 600 grams of semi-strong wheat flour;", "200 grams of semolina;", "200 grams of potato flour starch;", "20 grams of sodium chloride;", "1 gram of disodium phosphate;", "30 grams of rice oil;", "and 320 grams of water.", "The material of the outer layers is a mixture of: 300 grams of semi-strong wheat flour;", "200 grams of semolina;", "500 grams of potato flour starch;", "20 grams of sodium chloride;", "1 gram of disodium phosphate;", "30 grams of rice oil;", "and 340 grams of water.", "Each mixture was kneaded and rolled into a dough sheet.", "The ratio of thickness of the inner layer sheet to that of each outer layer was 1:1.", "The sheets were then rolled with the inner layer sheet interposed between the outer layers sheets to form a 2 mm thick paste, which was cut into 2 mm wide strips.", "The strips were boiled for 4 minutes and cooled.", "For purposes of consumption, the strips were boiled for 2 minutes and became spagetti-like textured.", "EXAMPLE 6 This example illustrates Method (6).", "The material of the inner layer was a mixture of: 1,000 grams of strong wheat flour;", "15 grams of sodium chloride;", "and 350 grams of water.", "The material of the outer layers was a mixture of: 1,000 grams of weak wheat flour;", "15 grams of sodium chloride;", "and 350 grams of water.", "Each mixture was kneaded and rolled into a dough sheet.", "The ratio of thickness of the inner layer sheet to that of each outer layer sheet was 2:1.", "The sheets were then rolled with the inner layer sheet interposed between the outer layer sheets to form a 2 mm thick paste, which was then cut into 2.5 mm wide strips.", "For purposes of consumption, the Japanese noodle type strips were boiled for 10-15 minutes and became elastically textured and relatively transparent looking.", "EXAMPLE 7 This example also follows Method (1) for purposes of experimental comparison with a conventional single-layer noodle prepared by the addition to the flour of different amounts of protein.", "The material of the single-layer noodle and of the inner layer of the three-layer noodle was a mixture of: 1 kilogram (total) of semi-strong wheat flour and vital gluten powder;", "16 grams of sodium chloride;", "2 grams of Kansui water;", "and 320 grams of water.", "The material of the outer layers of the three-layer noodle was a mixture of: 1 kilogram of semi-strong wheat flour;", "15 grams of sodium chloride;", "2 grams of Kansui water;", "and 310 grams of water.", "The mixture for the single-layer noodle was kneaded and rolled into a 1.2 mm thick dough sheet.", "The mixtures for the three-layer noodle were kneaded and rolled in the same manner as Example 1 to form a 1.2 mm thick dough sheet.", "Each sheet was cut into 1.5 mm wide strips and steamed at 97°-100° C. for 1 minute and fried in 135° C. palm oil for 1.5 minutes.", "To prepare the noodles for consumption, the strips were boiled for 3 minutes and gave the results shown in Tables 1 and 2 below.", "EXAMPLE 8 This example also follows Method (4) for purposes of experimental comparison with a conventional single-layer noodle prepared by the addition to the flour of different amounts of starch.", "The material of the single-layer noodle and the outer layers of the three-layer noodle was each a mixture of: 1 kilogram (total) of semi-strong wheat flour and potato starch;", "20 grams of sodium chloride;", "3 grams of Kansui water;", "and 350 grams of water.", "The material of the inner layer of the three-layer noodle was a mixture of: 1 kilogram of semi-strong wheat flour;", "20 grams of sodium chloride;", "3 grams of Kansui water;", "and 350 grams of water.", "The mixture for the single-layer noodle was kneaded and rolled into a 0.95 mm thick dough sheet.", "The mixtures for the three-layer noodle were kneaded and rolled in the same manner as in Example 4 to form a 0.95 mm thick dough sheet.", "Each sheet was cut into 1.7 mm wide strips and steamed at 97°-100° C. for 2 minutes and dried in 85° C. air for 40 minutes.", "To prepare the noodles for consumption, the strips were put in 95° C. hot water for 4 minutes to give the results shown in Tables 3 and 4 below: TABLE 1______________________________________Applicant's three-layer noodle (Method (1))Amount in wt.", "% of vital gluten powder addedto inner layer (1) 5 10 20 40 60 80______________________________________Producibility (2) well well well well well some- what badSmoothness (4) high high high high some- some- what what low lowExpansion with some-Hot Water (3) what low low low low low highRestorability (4) high high high high some- some- what what low lowElasticity (4) some- high high high high some- what what low lowSmell or Odor (4) good good good good good some- what bad______________________________________ TABLE 2__________________________________________________________________________One-Layer noodleAmount in wt.", "% of vital gluten powderadded to noodle 5 10 20 40 60 80__________________________________________________________________________Producibility well well somewhat bad bad bad badSmoothness high somewhat low low low low badExpansion with HotWater low low low low low lowRestorability high somewhat low low low low lowElasticity somewhat high high somewhat low low low lowSmell or Odor somewhat bad bad bad bad bad bad__________________________________________________________________________ TABLE 3______________________________________Applicants'three-layer noodleAmount in wt.", "% of starch added to outer layer 5 20 40 60 90______________________________________Producibility well well well well somewhat wellSmoothness some- some- high very very high what what high low lowExpansion with some- little little little littleHot water what greatRestorability low high high high highElasticity some- some- high very very high what what high low low______________________________________ TABLE 4______________________________________One-layer noodleAmount in wt.", "% of starch added to noodle 5 20 40 60 90______________________________________Producibility well well some- not produ- not pro- what cible when ducible well noodles are thinner than 1.5mmSmoothness low some- high what lowExpansion withHot Water great great littleRestorability low low highElasticity low some- high what low______________________________________ NOTES:- (1) The percentage by weight of the amount of vital glutan powder or starch is based on the total amount of the flour and the gluten powder or starch added thereto;", "(2) "Producibility"", "means how well the noodle can be produced without breaks or cuts during rolling or cutting into (3) "Expansion with hot water"", "was observed 10 minutes after the noodles were restored with the hot water;", "and (4) "Smoothness", "Restorability", "Elasticity"", "and "Smell or Odor"", "were observed immediately after the noodles were restored with the hot water o by boiling as the case may be.", "As is apparent from Table 1 , the amount of vital glutan powder added to the inner layer may be within the range of 5-80 wt.", "% (based on the weight of the flour and protein) and should preferably be 10-50 wt.", "An amount of the vital gluten powder of less than 5 wt.", "% will have no substantial effect, while an amount of more than 80 wt.", "% produces all undesirable results with respect to all of the aspects of Table 1 except "expansion with hot water.", """, "As is apparent from Table 3, the amount of the starch added to the outer layers should be within the range of 5-90 wt.", "% (based on the weight of flour and starch) and preferably 20-60 wt.", "An amount of the starch of less than 5 wt.", "% will have no substantial effects while an amount of more than 90 wt.", "% will cause breaks in the noodles.", "Although the invention has been described with respect to certain preferred embodiments thereof, it is not intended to be limited thereto but, instead, includes all those embodiments within the scope and spirit of the appended claims." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a light measuring circuit consisting of a photocurrent amplifying circuit which amplifies a current produced from a photoelectric conversion element and, more particularly, to a circuit which prevents the output of the photocurrent amplifying circuit from being saturated by a DC component. 2. Description of the Prior Art Known photocurrent amplifying circuits includes a circuit which excels in linearity and responsivity and is capable of detecting a weak, relatively high frequency pulse-like light signal coming under an ambient light (external light) which extensively varies in a DC-like manner or at a low frequency (flicker). Unlike the photo-current amplifying circuits used for optical communication devices of pulse code modulation (PCM) systems, optical character readers, etc., the photocurrent amplifying circuit of this kind has been arranged, for example, as shown in FIG. 1 of the accompanying drawings. The amplifying circuit shown in FIG. 1 has a negative feedback loop which includes a parallel connection circuit, formed by a T type low-pass filter circuit consisting of resistors R1 and R2 and a capacitor C having one terminal connected to a node between the resistors R1 and R2 and the other terminal grounded, and a gain limiting resistor R3 of a high resistance value disposed in between the output terminal 3 and the inverting input terminal 2 of an operational amplifier OP which has a high input impedance and has its non-inverting input terminal 1 grounded. A photoelectric conversion element PD (photogalvanic element), such as a photodiode which receives the light signal mentioned above, is connected between the input terminals 1 and 2 of the operational amplifier OP. The signal is taken out in the form of a photocurrent. The light signal is thus detected in a state of having good linearity over a wide range. With the amplifying circuit arranged in this manner, assuming that the output current of the photoelectric conversion element PD, i.e. the photocurrent, is expressed as ip, the output voltage Vout of the amplifying circuit can be generally expressed as: ##EQU1## In a low frequency region of ω≈0 in particular, the output voltage becomes: ##EQU2## In a frequency region which is expressed as ##EQU3## it can be expressed as follows: Vout=R3·ip (3) As will be understood from Formula (2) above, in the low frequency region, the output of the amplifying circuit is determined by the sum (R1+R2) of the resistance values of the resistors R1 and R2. In a high frequency region, the amplifying circuit output is determined by the value of the resistor R3 as will be understood from Formula (3) above. Therefore, with the resistance value of the resistor R3 arranged to be a large value and the sum (R1+R2) of the resistance values of the resistors R1 and R2 arranged to be small, the signal component representing the ambient light can be suppressed while a signal component of a given frequency, representing a signal light to be handled, can be emphatically taken out. However, in the amplifying circuit arranged in this manner, the provision of T type low-pass filter circuit, consisting of the resistors R1 and R2 and the capacitor C in the negative feedback loop, causes a noise component generated at the operational amplifier OP to be also amplified. Compared with an arrangement having the resistor R3 solely included in the negative feedback loop of the operational amplifier OP, the noise component in the signal becomes larger. This results in a salient deterioration of the S/N ratio of the whole amplifying circuit. Assuming that an operational amplifier having an FET input terminal is employed as the operational amplifier OP and that a current noise and a thermal noise are negligible, with a noise voltage which arises at the inverting input terminal 2 of the operational amplifier OP assumed to be en 2 , a noise voltage Von 2 which arises at the output terminal 3 is expressed as follow: ##EQU4## In the low frequency region of ω≈0, the noise voltage becomes as expressed below: Von.sup.2 ≈en.sup.2 ( 5) Further, in the high frequency region of ω≈∞, it becomes: ##EQU5## In other words, in a given frequency region, the noise is increased by (1+(R3/R1)) times because of AC amplification as compared with an arrangement having the resistor R3 solely provided in the negative feedback loop of the operational amplifier OP. This is further explained with reference to FIG. 2. FIG. 2 shows an AC circuit equivalent to the photocurrent amplifying circuit of FIG. 1. For an AC component, the impedance of the capacitor C is negligible. Therefore, the T type low-pass filter of FIG. 1 does not function as a filter and is considered equivalent to an arrangement having the resistor R1 connected between the inverting input terminal 2 of the operational amplifier OP and a grounding point as shown in FIG. 2. Further, the resistor R2 is equivalent to an arrangement having it connected as a load resistor between the output terminal of the amplifier OP and a grounding point. In FIG. 2, a reference symbol en denotes an equivalent voltage source reducing the input of noise generated by the operational amplifier OP by itself. However, in the case of a feedback arrangement, the non-inverting input terminal 1 and the inverting input terminal 2 have equal potentials. Therefore, with a bias current flowing to the inverting input terminal 2 of the operational amplifier OP not taken into consideration, the noise voltage en appears at the output terminal 3 of the operational amplifier OP in a state of having been amplified by the resistance value ratio between the resistors R1 and R3. It will be qualitatively understood that the noise component thus increases. In order to prevent the output of the amplifying circuit from being satuarated by the DC photocurrent resulting from an ambient light with the conventional photocurrent amplifying circuit arranged as shown in FIG. 1, a DC removing ratio γ=(R1+R2)/R3 should be arranged to be sufficiently small. However, the degree of noise amplification becomes too large for handling a weak signal. Therefore, there is a reducible limit to the DC removing ratio. Hence, the values of the resistors R1, R2 and R3 are generally determined according to a compromising point between a DC removing ration and a noise amplifying degree. As a result, it has been a drawback of the conventional arrangement that both the DC removing ratio and the noise amplifying degree become inadequate. To solve this problem, in cases where the above-stated amplifying circuit is to be used, it has been necessary to have another circuit or an optical system arranged to perform an additional function of compensating for the inadequacy of the DC removing ratio or the noise amplifying degree. SUMMARY OF THE INVENTION This invention is directed to the solution of the above-stated problems of the prior art. It is therefore an object of this invention to provide a photocurrent amplifying circuit which is provided with means operating according to the level of the low frequency component of the output of a photoelectric conversion element and is arranged to absorb the low frequency component of a signal corresponding to the output of the photoelectric conversion element by this means. The above and further objects and features of this invention will become apparent from the following detailed description of preferred embodiments thereof taken in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram showing a photocurrent amplifying circuit as an example of the prior art. FIG. 2 is a circuit diagram showing an AC equivalent circuit which is equivalent to the circuit of FIG. 1. FIG. 3 is a circuit diagram showing a first embodiment example of this invention. FIG. 4 is a graph showing the frequency characteristic of the circuit of the first embodiment example. FIG. 5 is a circuit diagram showing an AC equivalent to the circuit of FIG. 3. FIG. 6 is a diagram showing the circuit arrangement of a second embodiment example of this invention. FIG. 7 is a diagram showing the circuit arrangement of a third embodiment example of this invention. FIG. 8 is a diagram showing the circuit arrangement of a further embodiment example of this invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 shows in a circuit diagram a first embodiment example of this invention. The embodiment includes a T type low-pass filter which is formed by resistors R1 and R2 and a capacitor C arranged in the negative feedback loop of an operational amplifier OP in the conventional manner. To this conventional circuit arrangement is added a DC current absorbing transistor TR which has the base thereof connected to a node 4 between the resistors R1 and R2. The photocurrent amplifying circuit shown in FIG. 3 operates as follows: In the case of the conventional circuit shown in FIG. 1, the amplifying degree for the DC (or low frequency) component of a photocurrent ip and the amplifying degree for the signal (high frequency) component of the photocurrent ip are determined solely by the resistance value of the negative feedback loop as indicated by Formulas (2) and (3). In the first embodiment example of this invention shown in FIG. 3, however, the transistor TR acts to change the gain for a low frequency current. In the event that the photocurrent ip consists solely of an AC component including no low frequency component, the photocurrent ip flows via the resistor R3 to the output terminal of the operational amplifer OP to give an AC output voltage Vout=R3·ip in the same manner as the conventional circuit. For the AC component, there is no feedback by the T type filter with the capacitor C assumed to be short-circuited. Therefore, in that event, there is no difference between the potentials of the base and emitter of the transistor TR as no voltage drop is caused by the resistor R1. The transistor TR thus remains inoperative. Therefore, the conventional circuit operation as described in the foregoing with reference to Formulas (1) to (3) applies. The same condition also obtains in cases where only small amount of a low frequency current is included in the photocurrent ip and the voltage drop due to the resistor R1 is not large enough to render the transistor TR operative. In other words, as long as the voltage drop of the resistor R1 (a drop in the voltage applied between the base and emitter of the transistor TR) due to the low frequency component of the photocurrent ip remains below a value (generally 0.6 V or thereabout) required for rendering the transistor TR operative, the circuit arrangement of this embodiment operates in exactly the same manner as the operation of the conventional circuit. In case that the low frequency component of the photocurrent ip is large enough to have the resistor R1 bring about a sufficient voltage drop VBE for rendering the transistor TR operative, the embodiment operates as follows: When a voltage larger than 0.6 V is applied between the base and emitter of the transistor TR as a result of an increase in the low frequency component of the photo current ip, a portion of the photocurrent ip flows between the emitter and collector of the transistor TR and the low frequency component of the photocurrent ip flowing to the resistor R1 is bypassed. Then, even if the low frequency component of the photocurrent ip generated at the photodiode PD increases and comes to try to increase the photocurrent flowing to the resistor R1, the transistor acts to have a current flow between its emitter and collector in a larger amount. As a result, a portion of the low frequency component of the photocurrent ip which is flowing to the negative feedback loop of the operational amplifier OP becomes a value obtained by dividing the voltage (0.6 to 0.8 V or thereabout) by the resistance value of the resistor R1 and the amount of the current flowing to the negative feedback loop is not increased by the increase of the low frequency component of the photocurrent ip. Therefore, if the value of the voltage BVE between the base and emitter of the transistor TR is arranged to be 0.8 V, the portion of the current flowing to the resistor R1 becomes 0.8/R1 (A) while the rest of the DC current flows to the emitter of the transistor TR. Therefore, the degree of voltage change which appears in the output Vout of the photocurrent amplifying circuit due to the DC current, is limited and does not come to exceed ##EQU6## so that the output can be effectively prevented from being saturated by the DC current. FIG. 4 shows in a graph an example of the frequency characteristic of the gain of the photocurrent amplifying circuit arranged according to this invention as shown in FIG. 3. In this example, the constants as follows: R1=180 KΩ; R2=39 KΩ, R3=2.2 MΩ and C=0.47 μF. The frequency characteristic is arranged to be such that the gain becomes a maximum value at 10 KHz to make the circuit most suited for receiving a signal light modulated by a frequency of 10 KHz. In the case of this graph, when the DC current included in the photocurrent ip is less than 2 μA, the transistor TR does not operate and the frequency characteristic is determined solely by the T type filter. However, as shown, the transistor TR operates to further suppress the gain for the DC light while keeping the gain for the signal light unvarying as the DC current increases to 4 μA, 8 μA and 16 μA. The noise amplifying degree of this circuit is as follows: FIG. 5 shows an AC equivalent circuit equivalent to the photocurrent amplifying circuit arranged according to this invention as shown in FIG. 3. The circuit of FIG. 5 differs from the conventional circuit example of FIG. 2 in that there is added a resistor Re. This resistor Re corresponds to a resistor between the base and emitter of the transistor TR of the circuit shown in FIG. 3. Assuming that the collector current of the transistor TR is Ic, the resistor Re can be expressed as shown below: ##EQU7## wherein k represents a Boltzmann constant; T absolute temperature; and q elementary charge, respectively. Therefore, in the case of this embodiment arranged as shown in the block diagram, the resistance value of the resistor Re becomes smaller, accordingly, as the amount of a current flowing to the transistor TR increases with the voltage drop increased at the resistor R1 due to a larger DC component of the photocurrent ip. Conversely, the voltage drop at the resistor R1 decreases, accordingly, as the DC component becomes smaller. When the transistor TR thus becomes inoperative, the resistance value of the resistor Re comes close to an infinity value. The noise amplifying degree of the circuit of this embodiment can be expressed, like in the case of the foregoing description of the prior art, by the following formula: ##EQU8## In Formula (8) above, R1∥Re represents the parallel resistance values of the resistors R1 and Re. Therefore, the noise amplifying degree of the circuit of this embodiment becomes a minimum value when the transistor TR is inoperative with the DC component of the photocurrent ip being at a small amount. When the DC component reaches a region of rendering the transistor TR operative, the resistance value of the resistor Re decreases and the noise amplifying degree increases, accordingly, as the current flowing to the transistor TR increases. As mentioned in the foregoing, the circuit of this embodiment is capable of effectively preventing the saturation of the output due to the DC current by virtue of the action of the transistor TR. Therefore, compared with the conventional circuit arrangement whereby the DC current is suppressed solely by means of the T type low-pass filter, the circuit arrangement of this embodiment permits the resistors R1 and R2 of the T type filter part to have larger resistance values. Such being the arrangement, even in cases where the transistor TR remains inoperative, the noise amplifying degree of the circuit can be suppressed to a smaller value than the conventional arrangement by increasing the resistance value of the resistors R1 and R2 of the T type low-pass filter, so that the S/N ratio can be improved to a great extent. When the DC component enters the region of rendering the transistor TR operative, the noise amplifying degree increases to deteriorate the S/N ratio. However, in cases where the circuit of this embodiment is applied to the signal processing circuit of the light receiving circuit in the automatic focusing device of a still picture camera or a video camera, the ambient conditions for the operation are greatly varying. Particularly, where an intense ambient light causes a great amount of DC current to flow from the photodiode of the light receiving circuit, the phototaking lens of the camera is stopped down. This gives a deeper depth of field to allow a certain degree of deterioration in the precision of the automatic focusing operation. Therefore, with the resistance values of the resistors R1, R2 and R3 of the negative feedback loop determined in such a way as to allow the transistor TR to operate only under the most unfavorable conditions where the ambient light other than a signal light is extremely intense. Such arrangement mitigates the fear of a deteriorated S/N ratio. Meanwhile, the fact that the S/N ratio can be improved under a normal condition under which the transistor TR remains inoperative gives a great advantage. FIG. 6 shows in a circuit diagram a second embodiment example of this invention. The second example differs from the first example shown in FIG. 3 in that a diode D is connected between the inverting input terminal 2 of the operational amplifier OP and the emitter of the transistor TR. In the first embodiment example, the transistor TR comes to operate when the voltage drop of the resistor R1 due to the DC current exceeds 0.6 V or thereabout. Whereas, with the diode D connected to the emitter of the transistor TR in the case of the second example, the voltage drop is furthered by the diode D. Therefore, the transistor TR does not come to operate until the voltage drop at the resistor R1 comes to exceed 1.2 V or thereabout. The arrangement of the second embodiment example is advantageous in cases where the conditions of a system using the photocurrent amplifying circuit, such as power supply voltage, etc., have a relatively greater allowance permitting the output voltage variations of the amplifying circuit due to the DC current up to a value between 1.2 V and 1.6 V or thereabout. In that case, the operating range of the transistor TR is limited within a range of much greater DC currents. The resistor R1 is allowed to have a relatively large resistance value to suppress the noise amplifying degree when the transistor TR remains within its non-operating range. The concept of the second embodiment example is furthered in a third embodiment example which is arranged as shown in FIG. 7. In the case of the third example, the transistor TR is arranged to become operative when the voltage drop at the resistor R1 due to the low frequency component of the photocurrent ip comes to exceed a value (2+R5/R6) VBE with the voltage drop value between the base and emitter of the transistor TR assumed to be about equal to the voltage drop value between those of another transistor TR2 and with that value expressed as BVE. The value of the DC current at which the transistor TR enters the operating range is freely adjustable not only to a value which is an integer number of times as large as the value BVE (diode voltage) but also to any other value by suitably selecting the resistance values of resistors R5 and R6. In each of the embodiment examples given in the foregoing, the T type low-pass filter is arranged in the negative feedback loop of the operational amplifier OP. Whereas, in the case of another embodiment example shown in FIG. 8, a circuit consisting of two stages of serially connected T type low-pass filters is inserted in the negative feedback loop of the operational amplifier OP. In this instance, the base of the transistor TR may be either connected to a node 5 between resistors R4 and R5, as shown in FIG. 8, or connected to a node 6 between resistors R5 and R6. However, with the base of the transistor TR connected to the node 5 between the resistors R4 and R5 as shown in FIG. 8, the characteristic of the low-pass filter becomes steeper than connecting it between the resistors R5 and R6. In accordance with this invention as described in the foregoing, the low frequency component of a signal corresponding to the output of the amplifying circuit amplifying the photocurrent produced from a photoelectric conversion element is bypassed according to the level of the low frequency component included in the output of the amplifying circuit. Therefore, the output of the photocurrent amplifying circuit can be prevented from being saturated by an ambient light component. The invention thus enhances the precision of the operation of a light measuring current.
A light measuring circuit, consisting of an amplifying circuit amplifying the output of a photoelectric conversion element, is arranged to detect the occurrence of a low frequency component in the output of the photoelectric conversion element that comes to exceed a given level and, upon detection of that, to bypass the output of the photoelectric conversion element to prevent the output of the amplifying circuit from being saturated by a DC light (external or ambient light).
Identify and summarize the most critical features from the given passage.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This invention relates to a light measuring circuit consisting of a photocurrent amplifying circuit which amplifies a current produced from a photoelectric conversion element and, more particularly, to a circuit which prevents the output of the photocurrent amplifying circuit from being saturated by a DC component.", "Description of the Prior Art Known photocurrent amplifying circuits includes a circuit which excels in linearity and responsivity and is capable of detecting a weak, relatively high frequency pulse-like light signal coming under an ambient light (external light) which extensively varies in a DC-like manner or at a low frequency (flicker).", "Unlike the photo-current amplifying circuits used for optical communication devices of pulse code modulation (PCM) systems, optical character readers, etc.", ", the photocurrent amplifying circuit of this kind has been arranged, for example, as shown in FIG. 1 of the accompanying drawings.", "The amplifying circuit shown in FIG. 1 has a negative feedback loop which includes a parallel connection circuit, formed by a T type low-pass filter circuit consisting of resistors R1 and R2 and a capacitor C having one terminal connected to a node between the resistors R1 and R2 and the other terminal grounded, and a gain limiting resistor R3 of a high resistance value disposed in between the output terminal 3 and the inverting input terminal 2 of an operational amplifier OP which has a high input impedance and has its non-inverting input terminal 1 grounded.", "A photoelectric conversion element PD (photogalvanic element), such as a photodiode which receives the light signal mentioned above, is connected between the input terminals 1 and 2 of the operational amplifier OP.", "The signal is taken out in the form of a photocurrent.", "The light signal is thus detected in a state of having good linearity over a wide range.", "With the amplifying circuit arranged in this manner, assuming that the output current of the photoelectric conversion element PD, i.e. the photocurrent, is expressed as ip, the output voltage Vout of the amplifying circuit can be generally expressed as: ##EQU1## In a low frequency region of ω≈0 in particular, the output voltage becomes: ##EQU2## In a frequency region which is expressed as ##EQU3## it can be expressed as follows: Vout=R3·ip (3) As will be understood from Formula (2) above, in the low frequency region, the output of the amplifying circuit is determined by the sum (R1+R2) of the resistance values of the resistors R1 and R2.", "In a high frequency region, the amplifying circuit output is determined by the value of the resistor R3 as will be understood from Formula (3) above.", "Therefore, with the resistance value of the resistor R3 arranged to be a large value and the sum (R1+R2) of the resistance values of the resistors R1 and R2 arranged to be small, the signal component representing the ambient light can be suppressed while a signal component of a given frequency, representing a signal light to be handled, can be emphatically taken out.", "However, in the amplifying circuit arranged in this manner, the provision of T type low-pass filter circuit, consisting of the resistors R1 and R2 and the capacitor C in the negative feedback loop, causes a noise component generated at the operational amplifier OP to be also amplified.", "Compared with an arrangement having the resistor R3 solely included in the negative feedback loop of the operational amplifier OP, the noise component in the signal becomes larger.", "This results in a salient deterioration of the S/N ratio of the whole amplifying circuit.", "Assuming that an operational amplifier having an FET input terminal is employed as the operational amplifier OP and that a current noise and a thermal noise are negligible, with a noise voltage which arises at the inverting input terminal 2 of the operational amplifier OP assumed to be en 2 , a noise voltage Von 2 which arises at the output terminal 3 is expressed as follow: ##EQU4## In the low frequency region of ω≈0, the noise voltage becomes as expressed below: Von.", "sup[.", "].2 ≈en.", "sup[.", "].2 ( 5) Further, in the high frequency region of ω≈∞, it becomes: ##EQU5## In other words, in a given frequency region, the noise is increased by (1+(R3/R1)) times because of AC amplification as compared with an arrangement having the resistor R3 solely provided in the negative feedback loop of the operational amplifier OP.", "This is further explained with reference to FIG. 2. FIG. 2 shows an AC circuit equivalent to the photocurrent amplifying circuit of FIG. 1. For an AC component, the impedance of the capacitor C is negligible.", "Therefore, the T type low-pass filter of FIG. 1 does not function as a filter and is considered equivalent to an arrangement having the resistor R1 connected between the inverting input terminal 2 of the operational amplifier OP and a grounding point as shown in FIG. 2. Further, the resistor R2 is equivalent to an arrangement having it connected as a load resistor between the output terminal of the amplifier OP and a grounding point.", "In FIG. 2, a reference symbol en denotes an equivalent voltage source reducing the input of noise generated by the operational amplifier OP by itself.", "However, in the case of a feedback arrangement, the non-inverting input terminal 1 and the inverting input terminal 2 have equal potentials.", "Therefore, with a bias current flowing to the inverting input terminal 2 of the operational amplifier OP not taken into consideration, the noise voltage en appears at the output terminal 3 of the operational amplifier OP in a state of having been amplified by the resistance value ratio between the resistors R1 and R3.", "It will be qualitatively understood that the noise component thus increases.", "In order to prevent the output of the amplifying circuit from being satuarated by the DC photocurrent resulting from an ambient light with the conventional photocurrent amplifying circuit arranged as shown in FIG. 1, a DC removing ratio γ=(R1+R2)/R3 should be arranged to be sufficiently small.", "However, the degree of noise amplification becomes too large for handling a weak signal.", "Therefore, there is a reducible limit to the DC removing ratio.", "Hence, the values of the resistors R1, R2 and R3 are generally determined according to a compromising point between a DC removing ration and a noise amplifying degree.", "As a result, it has been a drawback of the conventional arrangement that both the DC removing ratio and the noise amplifying degree become inadequate.", "To solve this problem, in cases where the above-stated amplifying circuit is to be used, it has been necessary to have another circuit or an optical system arranged to perform an additional function of compensating for the inadequacy of the DC removing ratio or the noise amplifying degree.", "SUMMARY OF THE INVENTION This invention is directed to the solution of the above-stated problems of the prior art.", "It is therefore an object of this invention to provide a photocurrent amplifying circuit which is provided with means operating according to the level of the low frequency component of the output of a photoelectric conversion element and is arranged to absorb the low frequency component of a signal corresponding to the output of the photoelectric conversion element by this means.", "The above and further objects and features of this invention will become apparent from the following detailed description of preferred embodiments thereof taken in connection with the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram showing a photocurrent amplifying circuit as an example of the prior art.", "FIG. 2 is a circuit diagram showing an AC equivalent circuit which is equivalent to the circuit of FIG. 1. FIG. 3 is a circuit diagram showing a first embodiment example of this invention.", "FIG. 4 is a graph showing the frequency characteristic of the circuit of the first embodiment example.", "FIG. 5 is a circuit diagram showing an AC equivalent to the circuit of FIG. 3. FIG. 6 is a diagram showing the circuit arrangement of a second embodiment example of this invention.", "FIG. 7 is a diagram showing the circuit arrangement of a third embodiment example of this invention.", "FIG. 8 is a diagram showing the circuit arrangement of a further embodiment example of this invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 shows in a circuit diagram a first embodiment example of this invention.", "The embodiment includes a T type low-pass filter which is formed by resistors R1 and R2 and a capacitor C arranged in the negative feedback loop of an operational amplifier OP in the conventional manner.", "To this conventional circuit arrangement is added a DC current absorbing transistor TR which has the base thereof connected to a node 4 between the resistors R1 and R2.", "The photocurrent amplifying circuit shown in FIG. 3 operates as follows: In the case of the conventional circuit shown in FIG. 1, the amplifying degree for the DC (or low frequency) component of a photocurrent ip and the amplifying degree for the signal (high frequency) component of the photocurrent ip are determined solely by the resistance value of the negative feedback loop as indicated by Formulas (2) and (3).", "In the first embodiment example of this invention shown in FIG. 3, however, the transistor TR acts to change the gain for a low frequency current.", "In the event that the photocurrent ip consists solely of an AC component including no low frequency component, the photocurrent ip flows via the resistor R3 to the output terminal of the operational amplifer OP to give an AC output voltage Vout=R3·ip in the same manner as the conventional circuit.", "For the AC component, there is no feedback by the T type filter with the capacitor C assumed to be short-circuited.", "Therefore, in that event, there is no difference between the potentials of the base and emitter of the transistor TR as no voltage drop is caused by the resistor R1.", "The transistor TR thus remains inoperative.", "Therefore, the conventional circuit operation as described in the foregoing with reference to Formulas (1) to (3) applies.", "The same condition also obtains in cases where only small amount of a low frequency current is included in the photocurrent ip and the voltage drop due to the resistor R1 is not large enough to render the transistor TR operative.", "In other words, as long as the voltage drop of the resistor R1 (a drop in the voltage applied between the base and emitter of the transistor TR) due to the low frequency component of the photocurrent ip remains below a value (generally 0.6 V or thereabout) required for rendering the transistor TR operative, the circuit arrangement of this embodiment operates in exactly the same manner as the operation of the conventional circuit.", "In case that the low frequency component of the photocurrent ip is large enough to have the resistor R1 bring about a sufficient voltage drop VBE for rendering the transistor TR operative, the embodiment operates as follows: When a voltage larger than 0.6 V is applied between the base and emitter of the transistor TR as a result of an increase in the low frequency component of the photo current ip, a portion of the photocurrent ip flows between the emitter and collector of the transistor TR and the low frequency component of the photocurrent ip flowing to the resistor R1 is bypassed.", "Then, even if the low frequency component of the photocurrent ip generated at the photodiode PD increases and comes to try to increase the photocurrent flowing to the resistor R1, the transistor acts to have a current flow between its emitter and collector in a larger amount.", "As a result, a portion of the low frequency component of the photocurrent ip which is flowing to the negative feedback loop of the operational amplifier OP becomes a value obtained by dividing the voltage (0.6 to 0.8 V or thereabout) by the resistance value of the resistor R1 and the amount of the current flowing to the negative feedback loop is not increased by the increase of the low frequency component of the photocurrent ip.", "Therefore, if the value of the voltage BVE between the base and emitter of the transistor TR is arranged to be 0.8 V, the portion of the current flowing to the resistor R1 becomes 0.8/R1 (A) while the rest of the DC current flows to the emitter of the transistor TR.", "Therefore, the degree of voltage change which appears in the output Vout of the photocurrent amplifying circuit due to the DC current, is limited and does not come to exceed ##EQU6## so that the output can be effectively prevented from being saturated by the DC current.", "FIG. 4 shows in a graph an example of the frequency characteristic of the gain of the photocurrent amplifying circuit arranged according to this invention as shown in FIG. 3. In this example, the constants as follows: R1=180 KΩ;", "R2=39 KΩ, R3=2.2 MΩ and C=0.47 μF.", "The frequency characteristic is arranged to be such that the gain becomes a maximum value at 10 KHz to make the circuit most suited for receiving a signal light modulated by a frequency of 10 KHz.", "In the case of this graph, when the DC current included in the photocurrent ip is less than 2 μA, the transistor TR does not operate and the frequency characteristic is determined solely by the T type filter.", "However, as shown, the transistor TR operates to further suppress the gain for the DC light while keeping the gain for the signal light unvarying as the DC current increases to 4 μA, 8 μA and 16 μA.", "The noise amplifying degree of this circuit is as follows: FIG. 5 shows an AC equivalent circuit equivalent to the photocurrent amplifying circuit arranged according to this invention as shown in FIG. 3. The circuit of FIG. 5 differs from the conventional circuit example of FIG. 2 in that there is added a resistor Re.", "This resistor Re corresponds to a resistor between the base and emitter of the transistor TR of the circuit shown in FIG. 3. Assuming that the collector current of the transistor TR is Ic, the resistor Re can be expressed as shown below: ##EQU7## wherein k represents a Boltzmann constant;", "T absolute temperature;", "and q elementary charge, respectively.", "Therefore, in the case of this embodiment arranged as shown in the block diagram, the resistance value of the resistor Re becomes smaller, accordingly, as the amount of a current flowing to the transistor TR increases with the voltage drop increased at the resistor R1 due to a larger DC component of the photocurrent ip.", "Conversely, the voltage drop at the resistor R1 decreases, accordingly, as the DC component becomes smaller.", "When the transistor TR thus becomes inoperative, the resistance value of the resistor Re comes close to an infinity value.", "The noise amplifying degree of the circuit of this embodiment can be expressed, like in the case of the foregoing description of the prior art, by the following formula: ##EQU8## In Formula (8) above, R1∥Re represents the parallel resistance values of the resistors R1 and Re.", "Therefore, the noise amplifying degree of the circuit of this embodiment becomes a minimum value when the transistor TR is inoperative with the DC component of the photocurrent ip being at a small amount.", "When the DC component reaches a region of rendering the transistor TR operative, the resistance value of the resistor Re decreases and the noise amplifying degree increases, accordingly, as the current flowing to the transistor TR increases.", "As mentioned in the foregoing, the circuit of this embodiment is capable of effectively preventing the saturation of the output due to the DC current by virtue of the action of the transistor TR.", "Therefore, compared with the conventional circuit arrangement whereby the DC current is suppressed solely by means of the T type low-pass filter, the circuit arrangement of this embodiment permits the resistors R1 and R2 of the T type filter part to have larger resistance values.", "Such being the arrangement, even in cases where the transistor TR remains inoperative, the noise amplifying degree of the circuit can be suppressed to a smaller value than the conventional arrangement by increasing the resistance value of the resistors R1 and R2 of the T type low-pass filter, so that the S/N ratio can be improved to a great extent.", "When the DC component enters the region of rendering the transistor TR operative, the noise amplifying degree increases to deteriorate the S/N ratio.", "However, in cases where the circuit of this embodiment is applied to the signal processing circuit of the light receiving circuit in the automatic focusing device of a still picture camera or a video camera, the ambient conditions for the operation are greatly varying.", "Particularly, where an intense ambient light causes a great amount of DC current to flow from the photodiode of the light receiving circuit, the phototaking lens of the camera is stopped down.", "This gives a deeper depth of field to allow a certain degree of deterioration in the precision of the automatic focusing operation.", "Therefore, with the resistance values of the resistors R1, R2 and R3 of the negative feedback loop determined in such a way as to allow the transistor TR to operate only under the most unfavorable conditions where the ambient light other than a signal light is extremely intense.", "Such arrangement mitigates the fear of a deteriorated S/N ratio.", "Meanwhile, the fact that the S/N ratio can be improved under a normal condition under which the transistor TR remains inoperative gives a great advantage.", "FIG. 6 shows in a circuit diagram a second embodiment example of this invention.", "The second example differs from the first example shown in FIG. 3 in that a diode D is connected between the inverting input terminal 2 of the operational amplifier OP and the emitter of the transistor TR.", "In the first embodiment example, the transistor TR comes to operate when the voltage drop of the resistor R1 due to the DC current exceeds 0.6 V or thereabout.", "Whereas, with the diode D connected to the emitter of the transistor TR in the case of the second example, the voltage drop is furthered by the diode D. Therefore, the transistor TR does not come to operate until the voltage drop at the resistor R1 comes to exceed 1.2 V or thereabout.", "The arrangement of the second embodiment example is advantageous in cases where the conditions of a system using the photocurrent amplifying circuit, such as power supply voltage, etc.", ", have a relatively greater allowance permitting the output voltage variations of the amplifying circuit due to the DC current up to a value between 1.2 V and 1.6 V or thereabout.", "In that case, the operating range of the transistor TR is limited within a range of much greater DC currents.", "The resistor R1 is allowed to have a relatively large resistance value to suppress the noise amplifying degree when the transistor TR remains within its non-operating range.", "The concept of the second embodiment example is furthered in a third embodiment example which is arranged as shown in FIG. 7. In the case of the third example, the transistor TR is arranged to become operative when the voltage drop at the resistor R1 due to the low frequency component of the photocurrent ip comes to exceed a value (2+R5/R6) VBE with the voltage drop value between the base and emitter of the transistor TR assumed to be about equal to the voltage drop value between those of another transistor TR2 and with that value expressed as BVE.", "The value of the DC current at which the transistor TR enters the operating range is freely adjustable not only to a value which is an integer number of times as large as the value BVE (diode voltage) but also to any other value by suitably selecting the resistance values of resistors R5 and R6.", "In each of the embodiment examples given in the foregoing, the T type low-pass filter is arranged in the negative feedback loop of the operational amplifier OP.", "Whereas, in the case of another embodiment example shown in FIG. 8, a circuit consisting of two stages of serially connected T type low-pass filters is inserted in the negative feedback loop of the operational amplifier OP.", "In this instance, the base of the transistor TR may be either connected to a node 5 between resistors R4 and R5, as shown in FIG. 8, or connected to a node 6 between resistors R5 and R6.", "However, with the base of the transistor TR connected to the node 5 between the resistors R4 and R5 as shown in FIG. 8, the characteristic of the low-pass filter becomes steeper than connecting it between the resistors R5 and R6.", "In accordance with this invention as described in the foregoing, the low frequency component of a signal corresponding to the output of the amplifying circuit amplifying the photocurrent produced from a photoelectric conversion element is bypassed according to the level of the low frequency component included in the output of the amplifying circuit.", "Therefore, the output of the photocurrent amplifying circuit can be prevented from being saturated by an ambient light component.", "The invention thus enhances the precision of the operation of a light measuring current." ]
TECHNICAL FIELD Field of the Invention The present invention generally relates to thin film repair and, more particularly, to the partial repair of thin film wiring nets using top-surface-metallurgy (or TSM) repair lines. BACKGROUND OF THE INVENTION Conventionally, after an entire Multi-Chip Thin Film (MCM TF) module is completed, a full electrical test, an ATF test, is performed to confirm the integrity of the completed wiring. If any defect is detected at this stage, an after thin film (ATF) repair using top-surface repair lines is performed to correct the defective nets. FIG. 1 shows a plan view of a typical MCM 100. In FIG. 1, chips 102, 104, 106, 108, 110, 112, and 114 are mounted to the top surface metallurgy (TSM) of MCM 100 using a Controlled-Collapsed-Chip-Connection (C4) configuration (not shown in this Figure). In FIG. 1 seven chip locations are shown. MCMs are not limited to this configuration, however, and may be any number of chips depending on the requirements of the application. Before mounting the chips 102 through 114, MCM 100 is tested to ensure that no open circuits or short circuits exist in MCM 100. If open circuits or short circuits are found, the MCM must be repaired. The conventional ATF repair strategy discards the entire original net wiring and reconstructs new net wiring using the top surface repair lines, modifying their lengths to match the required electrical properties of the deleted wiring net. This conventional ATF repair method has worked well for traditional MCM-TF manufacturing. For tight ground rule MCM-TF products, however, a drawback of this conventional repair process is that product yield is adversely affected if the number of nets requiring repair exceeds the number of available repair nets on the TSM. Referring again to FIG. 1, a typical pair of wiring nets 116, 118 are shown. For illustrative purposes, it is assumed that a short circuit exists between wiring nets 116, 118. The conventional repair process deletes the entire wiring nets 116, 118 by cutting wiring nets 116, 118 at C4 location 120. In this example, wiring nets 116, 118 are cut (also called deletes) at sites 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, and 148. The deleted wiring nets 116, 118 must be replaced using the TSM repair net (shown in FIG. 2A). FIGS. 2A and 2B shows a typical TSM repair net 200 for the MCM of FIG. 1. In FIG. 2A, repair net 200 is made up of x-lines 202 and y-lines 204. As shown in FIG. 2B, within the gridwork of repair net 200 are C4 connections 206 for each chip 102, 104, 106, 108, 110, 112, and 114 mounted on MCM 100. FIG. 2C shows an x-ray view of a five-layer MCM and FIG. 2D is a partial side view of MCM 100 illustrating the layered structure of MCM 100. In FIG. 2C, successive layers form MCM 100. Typical layers include ground layer 208, power layer 210, x-layer 212, and y-layer 214. An additional layer, top layer 216 (shown in FIG. 2D), contains repair net 200 and C4 connections 206. It is apparent from FIG. 2C that repair of an internal short circuit between any two x-layer lines or y-layer lines is a formidable task. For this reason, conventional repair processes deleted defective nets at the top layer 216. As mentioned above, conventional ATF repair is based on full repair. That is, the entire internal structure of a defective net is removed at its C4 connections 206. An entirely new set of wiring is reconstructed using repair net 200 and connected to the C4 connections 206 on the TSM. These full repairs are necessary because frequently the location of the defect in the defective net is unclear and the construction of a new net is the only practical way to repair the defective net. FIG. 2E illustrates a portion of a typical MCM before repair. In FIG. 2E, C4 connection 206 is connected to internal net 220 at via 238. X repair line 222 and Y repair lines 224, 226 are part of the top layer 216. Y repair lines 224, 226 are connected by Y repair line subway 236 using vias 228, 240. The reconstruction of the net is normally accomplished by joining the segments of the repair lines with individual gold slugs bonded to the TSM of the repair through conventional lasersonic bonding processes. The gold slugs interconnect specific X and Y repair line segments to rebuild the net topography. FIG. 2F illustrates the conventional repair process mentioned above. In FIG. 2F, when a short is found in internal net 220 it is completely disconnected from the circuit using external delete 230 between C4 connection 206 and via 238. This process is repeated at every other C4 connection location for internal net 220. To replace this deleted net, a portion of X repair line 222 and Y repair lines 224, 226 must be used. Conventionally, X repair line 222 and Y repair lines 224, 226 are cut using deletes 232. Then C4 connection 206 is connected to X repair line 222 and Y repair line 224 using gold slugs 234. The drawback of this approach is that a relatively large number of repair lines are consumed for nets with multiple segments. As illustrated in FIG. 2F, an X repair line and a Y repair line were necessary to replace internal net 220. This results in fewer nets being repairable. An additional drawback of this conventional repair process is the scrapping of a part if an input/output (I/O) net is identified as defective. This is because conventional repair processes can only repair top-to-top signal nets while an I/O site is connected within the layers of the device. Furthermore, because most defective nets run in the same general direction on the device, they require the use of the same top-surface repair lines. In such a case a part might be lost due to unroutability--insufficient repair lines to meet the repair requirements. SUMMARY OF THE INVENTION In view of the shortcomings of the prior art, it is an object of the present invention to increase MCM TF device yields by using a partial wiring net repair process. The present invention relates to a process for partially repairing defective MCM TF wiring nets. The process comprises the steps of locating a short circuit between any two nets of the thin-film device. After a short circuit is located, an internal site to cut (delete site) is identified in one of the nets, and only a portion of one of the shorted nets is deleted and repaired. This process is continued until all shorts are identified and repaired. It is understood that this process can also to repair open defects in the MCM TF. The process further determines any cuts to the first net such that the timing of the uncut net is not affected by antenna effects of the remaining portions of the first net. The present invention also relates to a process for maximizing the utility of TSM repair nets by deleting and repairing only a minimum portion of a defective net. The present invention finally relates to a process for removing a portion of each layer above a portion of a defective net and deleting a section of the defective net. It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the invention. BRIEF DESCRIPTION OF THE DRAWING The invention is best understood from the following detailed description when read in connection with the accompanying drawing. It is emphasized that, according to common practice, the various features of the drawing are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawing are the following Figures: FIG. 1 is a plan view of a typical MCM; FIG. 2A is a plan view of a typical TSM repair net for the MCM of FIG. 1; FIG. 2B is a detailed view of a portion of the repair net of FIG. 2A; FIG. 2C is an x-ray view of a portion of the MCM of FIG. 2A; FIG. 2D is a cross-sectional view of FIG. 2C taken along the line 2D--2D; FIG. 2E is a plan view of a portion of an MCM prior to repair; FIG. 2F is a plan view of a portion of the MCM of FIG. 2E after a conventional repair; FIG. 3 is a cross-sectional view of an MCM prior to application of the process of the present invention for repairing the MCM; FIG. 4 is a flow chart diagram illustrating an exemplary embodiment of the present invention; FIG. 5A is a schematic diagram showing a step in the process of FIG. 4; FIG. 5B is a schematic diagram showing a step in the process of FIG. 4; FIG. 5C is a schematic diagram showing a step in the process of FIG. 4; FIG. 5D is a schematic diagram showing a step in the process of FIG. 4; FIG. 6 is a partial plan view of an MCM using an exemplary partial repair process of the present invention; and FIG. 7 is a plan view of an MCM illustrating an exemplary perforating delete process of the present invention. DESCRIPTION OF THE INVENTION Referring now to the drawing, FIG. 3 is a cross-sectional view of a typical MCM layered structure. In FIG. 3, layers are successively formed to fabricate MCM 100 over substrate 320, such as a ceramic carrier, in the following order: power mesh layer 318, fourth polyimide layer 316, x-line layer 314, third polyimide layer 312, y-line layer 310, second polyimide layer 308, ground mesh layer 306, first polyimide layer 304, and TSM layer 302. It is understood that this arrangement of layers is exemplary and may be in any other order or may include additional layers depending on design requirements of the MCM. FIG. 4 is a flow chart diagram of an exemplary embodiment according to the present invention. This embodiment employs a process to delete a portion of a defective internal net in an MCM. The process shown in FIG. 4 is described below in conjunction with FIGS. 5A, 5B, 5C, and 5D. Once a short circuit is identified between two adjacent y-lines in y-line layer 310, for example, a laser (not shown) is used to delete a portion of one of the shorted y-lines. At Step 400, the MCM is inserted into the repair tool (not shown). At step 402, a first aperture 502 is formed (shown in FIG. 5A) in first polyimide layer 304. In the exemplary embodiment, first aperture 502 has a 65 μm×65 μm area, although an area of any size may be used depending on the topology of the MCM layers. It is preferred that first aperture 502 be about 2.5× the pitch (line width plus inter-line spacing) of the x or y lines. In this example, the line width is about 12.5 μm and the spacing is about 12.5 μm, resulting in a 25 μm pitch. First aperture 502 may be formed using laser pulses having an output power of about 1-2 J/cm 2 . The number and duration of laser pulses varies depending on the thickness of first polyimide layer 304 but may typically be between 10-20 pulses in order to expose the surface of ground mesh layer 306. At step 404, second aperture 504 (shown in FIG. 5B) is formed in ground mesh layer 306. Second aperture 504 completely penetrates ground mesh layer 306 and exposes the top surface of second polyimide layer 308. Second aperture 504 has an area smaller than the area of first aperture 502 and is preferably about 2× the pitch of the x or y lines. In the exemplary embodiment, second aperture 504 has a 50 μm×50 μm area. Second aperture 504 may be formed using laser pulses having an output power of about 10-30 J/cm 2 , with a preferred output power of 21 J/cm 2 . The number of laser pulses varies depending on the thickness of ground mesh layer 306 but may typically be 1 or 2 pulses in order to completely remove ground mesh 306 and expose the surface of second polyimide layer 308. At Step 406, any residual metal remaining after creating second aperture 504 is removed using between 5-10 laser pulses of 1-2 J/cm 2 each depending on the amount of residue remaining. At Step 408, third aperture 506 (shown in FIG. 5C) is formed in second polyimide layer 308 to expose a desired portion of y-line layer 310. Third aperture 506 has an area smaller than the area of second aperture 504 and is preferably about 1.45× the width of the x or y lines. In the exemplary embodiment, third aperture 506 has a 19 μm×19 μm area. Third aperture 506 may be formed using laser pulses having an output power of about 1-2 J/cm 2 . The number of laser pulses varies depending on the thickness of second polyimide layer 308 but may typically be between 10-20 pulses in order to completely expose the desired portion of the surface of y-line layer 310. At Step 410, internal delete 508 (shown in FIG. 5D) is formed in y-line layer 310 to eliminate the short circuit between the adjacent y-lines. Internal delete 508 has an area smaller than the area of third aperture 506 and is preferably about 1.2× the width of the y lines. In the exemplary embodiment, internal delete 508 has a 15 μm×15μm area. Internal delete 508 may be formed using laser pulses having an output power of about 10-20 J/cm 2 . The number of laser pulses varies depending on the thickness of y-line layer 310 but may typically be 1 or 2 pulses in order to completely remove the desired portion of y-line layer 310 without exposing any portion of the surface below y-line layer 310. At Step 412, any residual metal remaining after creating internal delete 508 is eliminated using between 5-10 laser pulses of 1-2 J/cm 2 each depending on the amount of residue remaining. Although the process outlined above describes removing a short circuit from y-line layer 310, it is understood that a short in x-line layer 314 may also be eliminated by avoiding cutting into the lines in y-line layer 310 and forming an internal delete in x-line layer 314. In this case, additional process steps are necessary to form an aperture in third polyimide layer 312 and an internal delete in x-line layer 314. FIG. 6 illustrates a partial plan view of an MCM using the partial repair process of an exemplary embodiment of the present invention. In FIG. 6, internal delete 600 is formed in net 220 to disconnect defective segment 604 from the non-defective portion 602 of defective net 220. The partial repair of defective net 220 is completed by connecting a portion of x repair line 222 to C4 connection 206 using gold slug 234. This exemplary repair process does not require using y repair lines 224, 226. Consequently, a fifty percent saving of available repair lines results. As stated earlier, partial repairs use about half of the repair lines. Therefore, by using a partial repair process, more defective nets in an MCM may be repaired resulting in higher device yields. Partial repair can also repair an I/O net if a defect occurs in a top-to-top portion of the I/O net. The partial repair process according to another exemplary embodiment of the present invention further reduces repair net usage by performing perforating deletes. Perforating deletes use the concept that the deleted segments need to be as small as possible to prevent the deleted segment from creating antenna noise pick-up in the wiring net which is shorted to the defective segment of the partially repaired net. There are certain acceptable segment lengths which are not prone to cause antenna effect. In a 5 nanosecond system, for example, a remaining segment can be no more than 1 cm long to avoid antenna effect. Extensive failure analysis has shown that there is greater than a 99% probability that a defective net has only one defect (short) in the net. Therefore, based on this probability, repairing the second net is avoided by cutting the defective segment of the first net into multiple pieces, with each piece being shorter than 1 cm, for example. FIG. 7 illustrates the perforating delete process. In FIG. 7, MCM 700 has chips 702, 704, 706, 708 and 710 interconnected by wiring nets 712, 714. For illustrative purposes it is assumed that a short is detected in wiring nets 712, 714 between chips 704 and 706 in segment 730 of wiring net 712 and segment 732 of wiring net 714. Segment 730 is located between C4 connections 722 and 726. Segment 732 is located between C4 connections 724 and 728. Segment 730 is disconnected from wiring net 712 using deletes 716 and 734. Segment 730 is still connected to wiring net 714 because of the short, however, resulting in antenna effect. To eliminate the antenna effect, segment 730 is cut into smaller segments using internal deletes 720 and 722, for example. In this example, the length of any portion of segment 730 is smaller than 1 cm. This length is determined, as mentioned above, based on the operating characteristics (i.e., timing, clock speed, etc.) of MCM 700. It is not necessary to determine which portion of segment 730 was shorted to wiring net 714 because the length of all portions of segment 730 are smaller than 1 cm. Perforation delete is useful to repair an I/O to non-I/O short. In this case, the non-I/O net is repaired and the portion shorted to the I/O net is perforation deleted. As a result, there is no need to repair the I/O net. Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.
A process for partially repairing defective Multi-Chip Module (MCM) Thin-Film (TF) wiring nets. The process comprises the steps of locating a short circuit between any two nets of the MCM, identifying a site to cut in one of the two nets, and deleting an internal portion of one of the two nets at the identified site.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "TECHNICAL FIELD Field of the Invention The present invention generally relates to thin film repair and, more particularly, to the partial repair of thin film wiring nets using top-surface-metallurgy (or TSM) repair lines.", "BACKGROUND OF THE INVENTION Conventionally, after an entire Multi-Chip Thin Film (MCM TF) module is completed, a full electrical test, an ATF test, is performed to confirm the integrity of the completed wiring.", "If any defect is detected at this stage, an after thin film (ATF) repair using top-surface repair lines is performed to correct the defective nets.", "FIG. 1 shows a plan view of a typical MCM 100.", "In FIG. 1, chips 102, 104, 106, 108, 110, 112, and 114 are mounted to the top surface metallurgy (TSM) of MCM 100 using a Controlled-Collapsed-Chip-Connection (C4) configuration (not shown in this Figure).", "In FIG. 1 seven chip locations are shown.", "MCMs are not limited to this configuration, however, and may be any number of chips depending on the requirements of the application.", "Before mounting the chips 102 through 114, MCM 100 is tested to ensure that no open circuits or short circuits exist in MCM 100.", "If open circuits or short circuits are found, the MCM must be repaired.", "The conventional ATF repair strategy discards the entire original net wiring and reconstructs new net wiring using the top surface repair lines, modifying their lengths to match the required electrical properties of the deleted wiring net.", "This conventional ATF repair method has worked well for traditional MCM-TF manufacturing.", "For tight ground rule MCM-TF products, however, a drawback of this conventional repair process is that product yield is adversely affected if the number of nets requiring repair exceeds the number of available repair nets on the TSM.", "Referring again to FIG. 1, a typical pair of wiring nets 116, 118 are shown.", "For illustrative purposes, it is assumed that a short circuit exists between wiring nets 116, 118.", "The conventional repair process deletes the entire wiring nets 116, 118 by cutting wiring nets 116, 118 at C4 location 120.", "In this example, wiring nets 116, 118 are cut (also called deletes) at sites 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, and 148.", "The deleted wiring nets 116, 118 must be replaced using the TSM repair net (shown in FIG. 2A).", "FIGS. 2A and 2B shows a typical TSM repair net 200 for the MCM of FIG. 1. In FIG. 2A, repair net 200 is made up of x-lines 202 and y-lines 204.", "As shown in FIG. 2B, within the gridwork of repair net 200 are C4 connections 206 for each chip 102, 104, 106, 108, 110, 112, and 114 mounted on MCM 100.", "FIG. 2C shows an x-ray view of a five-layer MCM and FIG. 2D is a partial side view of MCM 100 illustrating the layered structure of MCM 100.", "In FIG. 2C, successive layers form MCM 100.", "Typical layers include ground layer 208, power layer 210, x-layer 212, and y-layer 214.", "An additional layer, top layer 216 (shown in FIG. 2D), contains repair net 200 and C4 connections 206.", "It is apparent from FIG. 2C that repair of an internal short circuit between any two x-layer lines or y-layer lines is a formidable task.", "For this reason, conventional repair processes deleted defective nets at the top layer 216.", "As mentioned above, conventional ATF repair is based on full repair.", "That is, the entire internal structure of a defective net is removed at its C4 connections 206.", "An entirely new set of wiring is reconstructed using repair net 200 and connected to the C4 connections 206 on the TSM.", "These full repairs are necessary because frequently the location of the defect in the defective net is unclear and the construction of a new net is the only practical way to repair the defective net.", "FIG. 2E illustrates a portion of a typical MCM before repair.", "In FIG. 2E, C4 connection 206 is connected to internal net 220 at via 238.", "X repair line 222 and Y repair lines 224, 226 are part of the top layer 216.", "Y repair lines 224, 226 are connected by Y repair line subway 236 using vias 228, 240.", "The reconstruction of the net is normally accomplished by joining the segments of the repair lines with individual gold slugs bonded to the TSM of the repair through conventional lasersonic bonding processes.", "The gold slugs interconnect specific X and Y repair line segments to rebuild the net topography.", "FIG. 2F illustrates the conventional repair process mentioned above.", "In FIG. 2F, when a short is found in internal net 220 it is completely disconnected from the circuit using external delete 230 between C4 connection 206 and via 238.", "This process is repeated at every other C4 connection location for internal net 220.", "To replace this deleted net, a portion of X repair line 222 and Y repair lines 224, 226 must be used.", "Conventionally, X repair line 222 and Y repair lines 224, 226 are cut using deletes 232.", "Then C4 connection 206 is connected to X repair line 222 and Y repair line 224 using gold slugs 234.", "The drawback of this approach is that a relatively large number of repair lines are consumed for nets with multiple segments.", "As illustrated in FIG. 2F, an X repair line and a Y repair line were necessary to replace internal net 220.", "This results in fewer nets being repairable.", "An additional drawback of this conventional repair process is the scrapping of a part if an input/output (I/O) net is identified as defective.", "This is because conventional repair processes can only repair top-to-top signal nets while an I/O site is connected within the layers of the device.", "Furthermore, because most defective nets run in the same general direction on the device, they require the use of the same top-surface repair lines.", "In such a case a part might be lost due to unroutability--insufficient repair lines to meet the repair requirements.", "SUMMARY OF THE INVENTION In view of the shortcomings of the prior art, it is an object of the present invention to increase MCM TF device yields by using a partial wiring net repair process.", "The present invention relates to a process for partially repairing defective MCM TF wiring nets.", "The process comprises the steps of locating a short circuit between any two nets of the thin-film device.", "After a short circuit is located, an internal site to cut (delete site) is identified in one of the nets, and only a portion of one of the shorted nets is deleted and repaired.", "This process is continued until all shorts are identified and repaired.", "It is understood that this process can also to repair open defects in the MCM TF.", "The process further determines any cuts to the first net such that the timing of the uncut net is not affected by antenna effects of the remaining portions of the first net.", "The present invention also relates to a process for maximizing the utility of TSM repair nets by deleting and repairing only a minimum portion of a defective net.", "The present invention finally relates to a process for removing a portion of each layer above a portion of a defective net and deleting a section of the defective net.", "It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the invention.", "BRIEF DESCRIPTION OF THE DRAWING The invention is best understood from the following detailed description when read in connection with the accompanying drawing.", "It is emphasized that, according to common practice, the various features of the drawing are not to scale.", "On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.", "Included in the drawing are the following Figures: FIG. 1 is a plan view of a typical MCM;", "FIG. 2A is a plan view of a typical TSM repair net for the MCM of FIG. 1;", "FIG. 2B is a detailed view of a portion of the repair net of FIG. 2A;", "FIG. 2C is an x-ray view of a portion of the MCM of FIG. 2A;", "FIG. 2D is a cross-sectional view of FIG. 2C taken along the line 2D--2D;", "FIG. 2E is a plan view of a portion of an MCM prior to repair;", "FIG. 2F is a plan view of a portion of the MCM of FIG. 2E after a conventional repair;", "FIG. 3 is a cross-sectional view of an MCM prior to application of the process of the present invention for repairing the MCM;", "FIG. 4 is a flow chart diagram illustrating an exemplary embodiment of the present invention;", "FIG. 5A is a schematic diagram showing a step in the process of FIG. 4;", "FIG. 5B is a schematic diagram showing a step in the process of FIG. 4;", "FIG. 5C is a schematic diagram showing a step in the process of FIG. 4;", "FIG. 5D is a schematic diagram showing a step in the process of FIG. 4;", "FIG. 6 is a partial plan view of an MCM using an exemplary partial repair process of the present invention;", "and FIG. 7 is a plan view of an MCM illustrating an exemplary perforating delete process of the present invention.", "DESCRIPTION OF THE INVENTION Referring now to the drawing, FIG. 3 is a cross-sectional view of a typical MCM layered structure.", "In FIG. 3, layers are successively formed to fabricate MCM 100 over substrate 320, such as a ceramic carrier, in the following order: power mesh layer 318, fourth polyimide layer 316, x-line layer 314, third polyimide layer 312, y-line layer 310, second polyimide layer 308, ground mesh layer 306, first polyimide layer 304, and TSM layer 302.", "It is understood that this arrangement of layers is exemplary and may be in any other order or may include additional layers depending on design requirements of the MCM.", "FIG. 4 is a flow chart diagram of an exemplary embodiment according to the present invention.", "This embodiment employs a process to delete a portion of a defective internal net in an MCM.", "The process shown in FIG. 4 is described below in conjunction with FIGS. 5A, 5B, 5C, and 5D.", "Once a short circuit is identified between two adjacent y-lines in y-line layer 310, for example, a laser (not shown) is used to delete a portion of one of the shorted y-lines.", "At Step 400, the MCM is inserted into the repair tool (not shown).", "At step 402, a first aperture 502 is formed (shown in FIG. 5A) in first polyimide layer 304.", "In the exemplary embodiment, first aperture 502 has a 65 μm×65 μm area, although an area of any size may be used depending on the topology of the MCM layers.", "It is preferred that first aperture 502 be about 2.5× the pitch (line width plus inter-line spacing) of the x or y lines.", "In this example, the line width is about 12.5 μm and the spacing is about 12.5 μm, resulting in a 25 μm pitch.", "First aperture 502 may be formed using laser pulses having an output power of about 1-2 J/cm 2 .", "The number and duration of laser pulses varies depending on the thickness of first polyimide layer 304 but may typically be between 10-20 pulses in order to expose the surface of ground mesh layer 306.", "At step 404, second aperture 504 (shown in FIG. 5B) is formed in ground mesh layer 306.", "Second aperture 504 completely penetrates ground mesh layer 306 and exposes the top surface of second polyimide layer 308.", "Second aperture 504 has an area smaller than the area of first aperture 502 and is preferably about 2× the pitch of the x or y lines.", "In the exemplary embodiment, second aperture 504 has a 50 μm×50 μm area.", "Second aperture 504 may be formed using laser pulses having an output power of about 10-30 J/cm 2 , with a preferred output power of 21 J/cm 2 .", "The number of laser pulses varies depending on the thickness of ground mesh layer 306 but may typically be 1 or 2 pulses in order to completely remove ground mesh 306 and expose the surface of second polyimide layer 308.", "At Step 406, any residual metal remaining after creating second aperture 504 is removed using between 5-10 laser pulses of 1-2 J/cm 2 each depending on the amount of residue remaining.", "At Step 408, third aperture 506 (shown in FIG. 5C) is formed in second polyimide layer 308 to expose a desired portion of y-line layer 310.", "Third aperture 506 has an area smaller than the area of second aperture 504 and is preferably about 1.45× the width of the x or y lines.", "In the exemplary embodiment, third aperture 506 has a 19 μm×19 μm area.", "Third aperture 506 may be formed using laser pulses having an output power of about 1-2 J/cm 2 .", "The number of laser pulses varies depending on the thickness of second polyimide layer 308 but may typically be between 10-20 pulses in order to completely expose the desired portion of the surface of y-line layer 310.", "At Step 410, internal delete 508 (shown in FIG. 5D) is formed in y-line layer 310 to eliminate the short circuit between the adjacent y-lines.", "Internal delete 508 has an area smaller than the area of third aperture 506 and is preferably about 1.2× the width of the y lines.", "In the exemplary embodiment, internal delete 508 has a 15 μm×15μm area.", "Internal delete 508 may be formed using laser pulses having an output power of about 10-20 J/cm 2 .", "The number of laser pulses varies depending on the thickness of y-line layer 310 but may typically be 1 or 2 pulses in order to completely remove the desired portion of y-line layer 310 without exposing any portion of the surface below y-line layer 310.", "At Step 412, any residual metal remaining after creating internal delete 508 is eliminated using between 5-10 laser pulses of 1-2 J/cm 2 each depending on the amount of residue remaining.", "Although the process outlined above describes removing a short circuit from y-line layer 310, it is understood that a short in x-line layer 314 may also be eliminated by avoiding cutting into the lines in y-line layer 310 and forming an internal delete in x-line layer 314.", "In this case, additional process steps are necessary to form an aperture in third polyimide layer 312 and an internal delete in x-line layer 314.", "FIG. 6 illustrates a partial plan view of an MCM using the partial repair process of an exemplary embodiment of the present invention.", "In FIG. 6, internal delete 600 is formed in net 220 to disconnect defective segment 604 from the non-defective portion 602 of defective net 220.", "The partial repair of defective net 220 is completed by connecting a portion of x repair line 222 to C4 connection 206 using gold slug 234.", "This exemplary repair process does not require using y repair lines 224, 226.", "Consequently, a fifty percent saving of available repair lines results.", "As stated earlier, partial repairs use about half of the repair lines.", "Therefore, by using a partial repair process, more defective nets in an MCM may be repaired resulting in higher device yields.", "Partial repair can also repair an I/O net if a defect occurs in a top-to-top portion of the I/O net.", "The partial repair process according to another exemplary embodiment of the present invention further reduces repair net usage by performing perforating deletes.", "Perforating deletes use the concept that the deleted segments need to be as small as possible to prevent the deleted segment from creating antenna noise pick-up in the wiring net which is shorted to the defective segment of the partially repaired net.", "There are certain acceptable segment lengths which are not prone to cause antenna effect.", "In a 5 nanosecond system, for example, a remaining segment can be no more than 1 cm long to avoid antenna effect.", "Extensive failure analysis has shown that there is greater than a 99% probability that a defective net has only one defect (short) in the net.", "Therefore, based on this probability, repairing the second net is avoided by cutting the defective segment of the first net into multiple pieces, with each piece being shorter than 1 cm, for example.", "FIG. 7 illustrates the perforating delete process.", "In FIG. 7, MCM 700 has chips 702, 704, 706, 708 and 710 interconnected by wiring nets 712, 714.", "For illustrative purposes it is assumed that a short is detected in wiring nets 712, 714 between chips 704 and 706 in segment 730 of wiring net 712 and segment 732 of wiring net 714.", "Segment 730 is located between C4 connections 722 and 726.", "Segment 732 is located between C4 connections 724 and 728.", "Segment 730 is disconnected from wiring net 712 using deletes 716 and 734.", "Segment 730 is still connected to wiring net 714 because of the short, however, resulting in antenna effect.", "To eliminate the antenna effect, segment 730 is cut into smaller segments using internal deletes 720 and 722, for example.", "In this example, the length of any portion of segment 730 is smaller than 1 cm.", "This length is determined, as mentioned above, based on the operating characteristics (i.e., timing, clock speed, etc.) of MCM 700.", "It is not necessary to determine which portion of segment 730 was shorted to wiring net 714 because the length of all portions of segment 730 are smaller than 1 cm.", "Perforation delete is useful to repair an I/O to non-I/O short.", "In this case, the non-I/O net is repaired and the portion shorted to the I/O net is perforation deleted.", "As a result, there is no need to repair the I/O net.", "Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown.", "Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention." ]
FIELD OF THE INVENTION This invention relates in general to semiconductor fabrication, and more particularly to a low temperature ion beam assisted deposition method for realizing SiGe/Si heterostructures. BACKGROUND OF THE INVENTION Ion beam deposition techniques are well known in the field of integrated circuit fabrication. These techniques are of interest because of the capability of ion beam deposition to grow thin film semiconductor layers. The kinetic energy of the ions can enhance the likelihood of epitaxial growth at lower substrate temperatures than are possible with prior art thermal evaporation techniques. Most prior art ion beam deposition techniques utilize sputtering (see T. Ohmi, K. Matsudo, T. Shibata, T. Ichikawa, Appl. Phys. Lett. 53, 364, (1988)). The use of a Si + beam for direct deposition onto a Si substrate is another alternative which has been utilized for Si epitaxy at low substrate temperatures, as described in K. J. Orrman-Rossiter, A. H. Al-Bayati, D. G. Armour, S. E. Donnely, and J. A. van den Berg, Nucl. Instrum. Methods B 59/60, 197 (1991), and A. H. Al-Bayati, K. J. Boyd, D. Marton, S. S. Todorov, J. W. Rabakais, Z. H. Zhong and W. K. Chu, J. Appl. Phys. 76, 4383 (1994). Plasma enhanced chemical vapor deposition, although mostly a chemical reaction technique, also utilizes energetic reactive ions, neutral excited molecules and radicals to enhance the growth rate of semiconductor films, as described in T. J. Donahue and R. Reif, J. Appl. Phys. 2757 (1985). All of the prior art MBE and CVD techniques utilize high growth temperatures and expensive equipment. SUMMARY OF THE INVENTION According to the present invention, two techniques are provided for utilizing ion beams to realize epitaxial grown films of SiGe, Si or Ge, on Si substrates. The first approach utilizes ion beam assisted deposition (IBAD) in conjunction with thermal co-evaporation of the elemental components. According to this technique, an ion beam is utilized to impart mobility to deposited adatoms. According to the second approach, the ion beam is used to deposit one of the components from ion-dissociation of gas molecules (e.g. Si from SiH 4 or Ge from GeH 4 ion beams), while the other components are provided by thermal co-evaporation. The processes of the present invention give rise to good quality epitaxial films at low temperatures (e.g. in the range of 250°-350° C.). The most important advantage of the methods according to the present invention over the prior art are that the films are processed entirely at low temperatures and hence can be used for post-IC modifications (e.g. to add additional critical devices to an integrated circuit (IC) chip). The processes of the present invention can be integrated into state of the art IC fabrication sequences to realize various Si devices and SiGe hetero-junction devices. The processes of the present invention avoid the requirement of expensive fabrication equipment. A broad description of applicant's first process is provided in applicant's publication entitled "A Low Temperature Ion-Beam Assisted Deposition Method for Realizing SiGe/Si Heterostructures", Solid State Electronics, Volume 37, No. 8, pages 1467-1469, August 1994. BRIEF DESCRIPTION OF THE DRAWINGS A detailed description of the invention and its preferred embodiment is provided below with reference to the following drawings, in which: FIG. 1 is a schematic diagram of a vacuum deposition chamber for implementing a first process in accordance with the present invention; FIG. 2 is a SIMS profile of a prepared SiGe film on a Si substrate using the process discussed in connection with FIG. 1. FIG. 3 is a Rutherford back scattering spectra for the SiGe film on Si substrate discussed in connection with FIG. 2. FIG. 4(a) is a high resolution image of the SiGe-Si interfacial region displaying the micro-crystalline nature of the SiGe growth layer discussed above in connection with FIGS. 1-3. FIG. 4(b) shows the <001> zone axis selected area selectron diffraction pattern. FIG. 5(a) is a schematic diagram showing the steps in fabrication of an SiGe-Si iso-type diode using the first process in accordance with the present invention. FIG. 5(b) depicts the electrical equivalent circuit for the diode of FIG. 5(a), wherein R s results primarily from both ohmic resistance and contact resistance. FIG. 6 shows the current-voltage characteristics of the SiGe-Si iso-type diode of FIGS. 5(a) and 5(b) at different ambient temperatures. The inset shows the characteristics at a temperature of 150° K. with an "ideality" factor of 1.08. FIG. 7 shows an Arrhenius plot of the SiGe Si iso-type diode of FIGS. 5(a) and (b). The dotted straight line superimposed on the plot indicates an energy barrier height of 0.38 eV for the majority carriers (i.e. electrons). FIG. 8 shows a severe degradation of current-voltage characteristics of the iso-type diodes of FIGS. 5(a) and (b) after rapid thermal annealing at 800° C. for 30 seconds. FIG. 9 is a schematic diagram of the deposition chamber utilized in accordance with the second process of the present invention. FIG. 10(a) is a scanning electron micrograph for a sample prepared at 700° C. substrate temperature. FIG. 10b) is a scanning electron micrograph of the sample in FIG. 10(a) tilted at 65°. FIG. 10(c) shows a sample prepared at 500° C. FIG. 10(d) shows the sample of FIG. 10(c) tilted at 65° C. FIG. 11 is a cross sectional transmission electron microscopy (TEM), in which FIG. 11(a) shows a bright field [110] zone axis image of one of a plurality of pyramids grown at 700° C. The insert shows the electron diffraction pattern for the films and the substrate. FIG. 11(b) shows a high resolution cross-sectional TEM image for the sample in FIG. 11(a). FIG. 12(a) is a bright field image of a sample grown at 300° C. FIG. 12(b) is a high resolution TEM image for the sample in FIG. 12(a) showing epitaxial growth. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Turning to FIG. 1, an experimental set-up is shown for implementing the first process in accordance with the present invention. A 45 cm diameter glass cylinder vacuum chamber 1 is evacuated using a mechanical pump backing a diffusion pump (not shown). A liquid nitrogen cold trap (not shown) is used to reduce the level of water vapor during the film deposition. A base pressure of 1×10 -7 Torr (1.3×10 -5 Pa) is maintained. Silicon 2 and germanium 4 are evaporated using an electron gun 3 and an indirectly heated AlO 2 crucible source, respectively. A commercial Kaufman type IonTek ion gun 3 is used to bombard the surface of a substrate 5 during film deposition. Ultra high pure (UHP grade) argon is used as the source gas for the ion beam. The ion beam is directed towards the substrate 5 at an angle of 20° with respect to the normal to the sample surface. According to actual experiment, <100>, 1 Ωcm n-type silicon wafers were used as the substrate 5. The back of the substrate was doped with phosporous to enhance its back-side ohmic contact. The substrate 5 was cleaned using standard RCA solution and given an HF dip just before loading into the deposition chamber 1. The ion beam energy and current were set to 75 eV and 15 mA, respectively. The substrate temperature during film growth was maintained at 260° C. and was monitored using a thermocouple (not shown) located at the back side of the substrate 5. The deposition rate was monitored using a crystal microbalance positioned close to the substrate 5, and an average growth rate of 5 nm per minute was measured, resulting in a n-type doping of 2×10 19 cm -3 . Phosphorus co-evaporation was carried out in-situ from source 7 to dope the deposited SiGe film. Since the deposition was carried out at a low substrate temperature, the sticking coefficient of the phosphorus was close to unity. FIG. 2 shows the SIMS profile for the SiGe/Si sample product in accordance with the above-described process. In this Figure, Ge is plotted on a linear scale which shows a sharp step in its profile at the interface. FIG. 2 shows the creation of a SiGe film with a varying Ge concentration. Based on the SIMS results, a 40% Ge concentration is observed close to the Si-Ge interface and it sharply drops to an average of 15% in the rest of the film. The sharp increase in the Ge concentration is as a result of inadequate control at the beginning of the evaporation. The SIMS results also show that there is a high level of oxygen incorporated into the SiGe film with concentrations in the order of 1×10 21 cm -2 . This high oxygen content is believed to be due mainly to the low vacuum condition and high partial pressure of water vapor during film deposition. In order to investigate the nature of the films, Rutherford back scattering (RBS) and Cross-sectional TEM were employed. The sample was annealed at an ambient temperature of 800° C. for 30 seconds using a rapid thermal processing system (RTP). FIG. 3 shows the RBS spectra for the annealed sample. The random spectrum in this figure corroborates the presence of a SiGe film on the Si substrate with an average Ge concentration of 15%. The Ge fraction inferred from RBS is seen to substantially agree with the SIMS profile of FIG. 2. In addition to germanium, RBS also shows evidence for the incorporation of argon and its concentration is more than 5%. the ionization efficiency limit of the ion gun 3 used in this experiment is believed to be responsible for this high concentration of Ar in the SiGe film. The ion beam generated using this type of ion-gun, consists of both ionized and non-ionized Ar atoms. The non-ionized portion of the Ar flow is not characterized by substantial kinetic energy (except for kinetic energy imparted by thermal energy) and when the Ar flow collides with the substrate 5, a portion of the non-ionized Ar atoms is buried in the growing film without any means to escape. It is known that Ar incorporation should be kept below 0.2% in order to facilitate crystal regrowth, since the presence of high percentages of Ar can affect the crystallinity of the SiGe layer and impact device electrical characteristics. Another peak in the RBS is observed in the random spectrum of FIG. 3 which is believed to be due to tungsten (W). The incorporation of this element is believed to originate from the sublimation of the hot cathode filament used inside the ion gun 3. The concentration of this element in the film is about 0.1%. the channelled spectrum in FIG. 3 shows a yield of 15-20% less than the random spectrum indicating a partial alignment in the film crystal structure. This partial alignment in the film can be due to the micro-crystal structure of the SiGe layer. The structure of the SiGe-Si interface was studied using transmission electron microscopy (TEM). TEM samples in (110) cross-section were prepared by a cleavage technique, as set forth in J. McCaffery, "Small-angle Cleavage of Semiconductors for Transmission Electron Microscopy", Ultramicroscopy, vol. 38, pp. 149-157, 1991. Plan view samples were prepared using standard ion milling techniques. All microscopy was performed using a Philips CM20 TEM operated at 200 kV. FIG. 4(a) shows a high resolution image of the annealed SiGe-Si interfracial region with the substrate 5 in a [110] zone axis orientation. The SiGe film is micro-crystalline and contrast due to the <111> fringes of individual crystals is clearly observable. Applying dark field diffraction contrast techniques, the sizes of the crystallites composing the micro-crystalline layer were found to range from 5 to 9 nm. FIG. 4(b) is a <001> selected area diffraction pattern obtained from a plan view of the specimen. The individual spots are due to the Si substrate 5. Sharp rings around each of the spots are produced by the SiGe film and give further evidence to the micro-crystalline nature of the SiGe layer. SiGe/Si iso-type diodes were fabricated using ion-beam assisted deposition according to the process described above, at a temperature of approximately 250° C. Starting with an n on n+ silicon wafer 8 (FIG. 5(a) (i)), a phosphorus doped SiGe film 10 was deposited (FIG. 5(a)(ii) followed by a deposition of aluminum contacts 12 on the film using a shadow masking technique. The aluminum deposition 14 on the back side completed the iso-type diode fabrication (FIG. 5(a)(iii). The completed diodes were annealed in Forming gas at 250° C. for 20 mins. The diode area in this experiment was 1.5×10 -2 cm -2 . Some randomly selected diodes were chosen to be installed in a low temperature micorprobe to study the device characteristics at different ambient temperatures. The current-voltage characteristics of the diodes were measured using a HP-4145B parameter analyzer. FIG. 5(b) shows a simple electrical equivalent circuit model for the iso-type diodes fabricated as described above. Since the saturation current in such diodes is fairly high, the influence of the series resistance R s is significant. Considering the current-voltage relation for a typical diode, the effect of series resistance R s on the diode characteristics can be determined. Part of the applied voltage on the diode (D), drops across this resistor (R s ), reducing the voltage appearing across the intrinsic junction to Vd as in: ##EQU1## where I and V d are the diode current and voltage, respectively. I o is the diode reverse saturation current, V tot is the total voltage applied across the diode and R s is the resistance in series with the junction. The series resistance is in part due to the bulk resistance of the substrate 8 and in part due to the contact resistance of the metallization 12 and 14. By lowering the temperature, the deleterious effects of the series resistance can be made less dominant. FIG. 6 shows the current-voltage characteristics of the iso-type diode of FIG. 5 measured at different ambient temperatures. At temperatures below 170K, an ideal exponential regime becomes apparent. The inset in FIG. 6 shows the I-V characteristic for an iso-type diode at a temperature of 150K with an ideality factor of 1.08 persisting over three decades of current and beyond this it is limited by the series resistance. The behaviour of the diode remains ideal for temperatures as low as the liquid nitrogen temperature where it is limited by the resolution capabilities of the parameter analyzer and level of noise. Both reverse saturation current as well as the forward current strongly depend on the ambient temperature. FIG. 7 shows the Arrhenius plot for the diode at an applied forward voltage of 0.1 V. The exponential decrease of the current with temperature suggests that there is a barrier at the film-substrate interface which blocks the flow of majority carriers (electrons). This barrier can be modeled as: ##EQU2## where I c shows the reverse saturation current and E b represents the energy barrier for majority carriers. Considering Eqn. (1) and ignoring the effect of the series resistance, the forward current at a voltage of 0.1 V can be obtained from: ##EQU3## The straight line superimposed on the experimental results of FIG. 7 shows the phenomenological current-temperature characteristics predicted by Eqn. (3) and based on this a barrier height of 0.38 eV is obtained. For temperatures below 130K, the measured current is more than that predicted by Eqn. (3), but at this point the resolution of the parameter analyzer becomes crucial since it cannot measure currents below 10 -11 A. the formation of such a barrier can be due to the presence of interface states at the SiGe-Si interface, similar to Schottky barrier formation. These states are mostly generated by the dangling bonds of the substrate Si atoms. The presence of such a barrier is not seen for the epitaxially grown SiGe films on Si substrate. FIG. 8 shows the current-voltage characteristics for this sample after rapid thermal annealing at 800° C. for 30 seconds. Although the thermal treatment time was short, it is seen to significantly degrade the I-V results. This extensive degradation of the diode behaviour can be accounted for by the activation of defects at the interface. As indicated by the I-V characteristics, the behaviour remains extremely non-ideal at all ambient temperatures. To summarize, the static electrical characteristics show good rectifying behaviour of the fabricated n+SiGe/n-Si iso-type hetero-junction diodes with an ideality factor close to unity. At room temperature the reverse saturation current is large and the I-V characteristic is mainly limited by the series resistance. At lower temperatures, it has been shown that the saturation current drops expoentially and the shadowing effect of the series resistance is minimized and the I-V characteristic of the diode exhibits a clear exponential regime. For a wide range of ambient temperatures (90° K.-180° K.), the diode exhibits exponential I-V characteristic with an ideality factor close to unity over three decades of current. Based on the temperature dependent electrical characteristics of this device and using a simple energy barrier model, it was found that an energy barrier of 0.38 eV appears to fit the observed characteristic as: ##EQU4## where E b denotes the energy barrier at the SiGe-Si junction. Although the SiGe-Si interface states can be responsible for the formation of such an energy barrier, they do not seem to degrade the I-V characteristics of the diode by causing generation or recombination currents that would affect the ideality factor. High temperature annealing of the film drastically degrades the electrical characteristics as seen by the I-V characteristics at all temperatures investigated. This non-ideal I-V behaviour is believed to be mainly due to the formation of recombination (or generation) centers at the interface. According to the second process of the present invention, an inexpensive ion beam vapor deposition technique is provided to grow thin semiconductor films derived from ion-dissociation of the semiconductor from gas molecules. According to experiment, silicon films were grown at different substrate temperatures and their atomic structures studied using electron microscopy. The equipment used for this study is illustrated in FIG. 9. A cylindrical vacuum chamber 11 is pumped by a diffusion pump (not shown), equipped with a liquid nitrogen cold trap (not shown) and backed by a rotary mechanical pump (not shown). A base pressure of 1×10 -7 Torr (1.3×10 -5 Pa) is typically attained. A commercially available IonTek Kaufman type ion source 13 was used to ionize the gas and to accelerate the ion beam towards the substrate. The ion gun 13 bombarded the surface of a substrate 15 at an angle of 20° with respect to the normal of its surface. The ion beam energy and current can be adjusted between 30-1000 eV and 0-30 mA, respectively. Ultra high purity argon and silane (SiH 4 ) gasses with 99.999% purity were used as sources for the ion beam. Alternatively, a Ge film can be grown by using GeH 4 as the source of gas molecules. For the gun 13 to operate, a chamber pressure of 0.5-2×10 -4 Torr (0.65-2.6×10 -2 Pa) is required. For testing purposes, 1Ω-cm n-type <100> Si substrates 15 were used. Each Si substrate was cleaned for 15 mins. in a standard RCA solution. Before loading the Si wafer into the chamber, it was etched in HF followed by a rinse with D.I. water and a N2 blow-dry. After loading the sample and pump-down cycle, the sample was heated to 300° C. In-situ cleaning of the substrate surface was done by argon ion bombardment prior to the start of deposition. This is a necessary step which significantly influences the quality of the grown film. A 200 eV argon ion beam was used to sputter-clean the substrate at a low substrate temperature (≈50° C.). This low energy ion cleaning was found to be sufficient to remove the native oxide. After 5 mins. of Ar ion bombardment, the Ar line was closed and the ion gun 13 was shut down. The substrate temperature was set by radiation heating from a tungsten filament (not shown) mounted in a stainless steel box. The substrate temperature was raised to a temperature in the range of 700° C. to 800° C. in about one minute, and held at that temperature from 30 seconds to 1 min., to anneal surface damage caused by the energetic ion bombardment. The high temperature annealing step before deposition can be eliminated if a proper Ar + -ion beam energy is used. This energy must be low to avoid damaging the substrate, yet it must be strong enough to remove a few monolayers of the native oxide or adsorbed molecules on the substrate surface. It has been found that an ion beam energy of 40 eV at a substrate temperature of 340° C. is sufficient to remove the few monolayers of oxide and absorbed molecules on the substrate without introducing significant damage. The substrate temperature was then lowered to its desired value (300°-700° C.) to start the deposition. However, planar growth of Si and SiGe films can be achieved at temperatures as low as 250° C. SiH 4 gas was introduced to the ion source 13 and the deposition took place at a chamber pressure of 8×10 -5 Torr (although deposition can be carried out a pressures as low as 5×10 -4 Torr.) During the film growth, an ion beam energy of 50 eV and a current of 13 mA were used. The ion beam intensity at the substrate surface was 30 μA cm -2 and it was measured by a Faraday cup. Following the deposition cycle, the substrate temperature was allowed to cool down. It was observed that at this pressure (8×10 -5 Torr), no deposition occurred on the parts of the substrate 15 which were not directly exposed to the ion gun. The as-grown samples produced by the above described process were used for an electron microscopy study. FIG. 10a shows a scanning electron microscopy (SEM) image of a sample grown at 700° C. Rectangle-based pyramids as large as 1 μm in length and 0.3 μm in height, oriented with the (100) directions parallel to the substrate, are observed. The micrograph also indicates that many of the pyramids have elongated rectangular bases which are believed to be due to preferential growth influenced by the direction of the incident ion beam. FIG. 10(b) displays the tilted image for the same sample. As shown in this figure, the surface is covered by pyramids with (111) and (113) faces exposed. FIG. 10(c) shows a micrograph of the sample grown at 500° C. evidencing 3-D growth. It appears that the substrate surface is more completely covered at this lower temperature. Although it is difficult to determine the exact thickness of these three-dimensional films, it is evident that at lower temperatures the pyramid heights are less and their distribution is more uniform. Since the kinetic energy of the ion beam is required to dissociate the SiH4 molecules, the total number of Si atoms deposited on the substrate is independent of the substrate temperature. At an ion beam energy of 50 eV, the thermal energy of molecules (kT) is about three orders of magnitude smaller than the ion kinetic energy. FIG. 19(d) shows a higher magnification SEM image for the same sample. The size of the pyramids is also smaller. The difference in the coverage of the substrate surface is believed to be due to differences in the Si adatom mobilities. Part of the adatom surface mobility derives from thermal energy gained from the substrate and part from the kinetic energy of the ion beam. At higher substrate temperatures the surface mobility of adatoms is high and they can travel further before they bond with the underlayer. This can result in the formation of islands which are elongated in a preferred direction under the influence of the ion beam. By lowering the temperature of the growth, the total surface mobility is reduced and the probability for planar growth is increased. To study the crystalline quality of the prepared samples, high resolution transmission electron microscopy (HRTEM) was used. In this study, a small angle cleavage technique was used for the TEM specimen preparations. FIG. 11(a) shows a bright field [110] zone axis image of the sample grown at 700° C. The exposed atomic planes, (111) and (113), are observed in this figure. FIG. 11(b) displays a high resolution cross-sectional TEM image for the film-substrate interface of this sample. Few interfacial defects are observed in this figure indicating a reasonably good quality film. Electron diffraction analysis also indicates that the islands are epitaxially grown. The sample prepared using a 700° C. substrate temperature shows a planar growth. FIG. 12(a) displays the bright field [110] zone axis image for this sample indicating planar growth. The bright spots at the film-substrate interface are believed to be due to disordered Si at the interface resulting from the energetic Ar ion bombardment, when there has been insufficient annealing. FIG. 12(b) depicts a high resolution micrograph of the same sample clearly showing the epitaxial growth. The high resolution image also shows the presence of a large concentration of twins and microtwins, originating from the interface. Inadequate in-situ cleaning is believed to be responsible for the observed planar defects. It is contemplated that the damage created due to the 200 eV Ar ion bombardment may be too significant to be adequately repaired by a short annealing time. In comparison with the image in FIG. 11(b), it is seen that the higher temperature growth (700° C.) repairs the damage produced by such energic Ar bombardment. Al-Bayati et al. have recently studied the effect of substrate temperature on film quality using a mass selected ion beam deposition technique (see ref. K. J. Orrman-Rossiter, A. H. Al-Bayati, D. G. Armour, S. E. Donnely and J. A. van den Berg, Nucl. Instrum. Methods B 59/60, 197 (1991); and A. H. Bayati, K. J. Boyd, D. Marton, S. S. Todorov, J. W. Rabalais, Z. H. Zhang and W. K. Chu, Appl. Phys., 57 2757 (1985)). In their study, substrate temperatures above 350° C. were found to degrade the quality of the Si films, which is a result which seems to corroborate the experimental observations conducted with respect to the present invention. Ge incorporation into the Si film can be accomplished by thermal evaporation of elemental Ge from a B-N crucible in a manner similar to that discussed above in connection with the first described process (FIGS. 1-8). A portion of the energy of the arriving Si adatoms is imparted to Ge adatoms thereby enhancing their surface mobility and hence the probability of epitaxial growth at reduced temperatures. In conclusion, a simple and inexpensive technique is provided according to the present invention for growing silicon and silicon-germanium thin films. Depending on the substrate temperature, the films exhibit one of either island or planar growth. With the substrate at a higher temperature, 3-D growth with pronounced pyramids was observed. By lowering the substrate temperature, the probability of achieving planar growth is enhanced. At a substrate temperature of 300° C., planar growth was realized. In-situ cleaning of the sample is an important step of the second described process according to the present invention, and this is achieved by Ar ion bombardment at low temperatures followed by an in-situ annealing. Results from high resolution transmission electron microscopy, electron diffraction, Raman spectroscopy and scanning electron microscopy confirm the crystalline quality of the films grown by this technique. In addition, electrical characteristics of gallium-doped P-N junction diodes, realized using this approach, show good rectifying behaviour. Specifically, gallium-doped p-n junction diodes have been fabricated according to the process of the present invention by opening windows on an already completed integrated circuit chip having aluminum metallization. Other embodiments and variations are possible within the sphere and scope of the present invention as defined by the claims appended hereto.
A low temperature ion-beam assisted deposition process, comprising the steps of cleaning at least one substrate, subjecting the substrate to a vacuum of at least 2×10 -4 Torr, heating the substrate to a temperature of at least 280° C., and directing an ion beam at the substrate, wherein the ion beam comprises ion-associated gas molecules of Si or Ge, so as to grow a thin epitaxial film of Si or Ge on the substrate.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "FIELD OF THE INVENTION This invention relates in general to semiconductor fabrication, and more particularly to a low temperature ion beam assisted deposition method for realizing SiGe/Si heterostructures.", "BACKGROUND OF THE INVENTION Ion beam deposition techniques are well known in the field of integrated circuit fabrication.", "These techniques are of interest because of the capability of ion beam deposition to grow thin film semiconductor layers.", "The kinetic energy of the ions can enhance the likelihood of epitaxial growth at lower substrate temperatures than are possible with prior art thermal evaporation techniques.", "Most prior art ion beam deposition techniques utilize sputtering (see T. Ohmi, K. Matsudo, T. Shibata, T. Ichikawa, Appl.", "Phys.", "Lett.", "53, 364, (1988)).", "The use of a Si + beam for direct deposition onto a Si substrate is another alternative which has been utilized for Si epitaxy at low substrate temperatures, as described in K. J. Orrman-Rossiter, A. H. Al-Bayati, D. G. Armour, S. E. Donnely, and J. A. van den Berg, Nucl.", "Instrum.", "Methods B 59/60, 197 (1991), and A. H. Al-Bayati, K. J. Boyd, D. Marton, S. S. Todorov, J. W. Rabakais, Z. H. Zhong and W. K. Chu, J. Appl.", "Phys.", "76, 4383 (1994).", "Plasma enhanced chemical vapor deposition, although mostly a chemical reaction technique, also utilizes energetic reactive ions, neutral excited molecules and radicals to enhance the growth rate of semiconductor films, as described in T. J. Donahue and R. Reif, J. Appl.", "Phys.", "2757 (1985).", "All of the prior art MBE and CVD techniques utilize high growth temperatures and expensive equipment.", "SUMMARY OF THE INVENTION According to the present invention, two techniques are provided for utilizing ion beams to realize epitaxial grown films of SiGe, Si or Ge, on Si substrates.", "The first approach utilizes ion beam assisted deposition (IBAD) in conjunction with thermal co-evaporation of the elemental components.", "According to this technique, an ion beam is utilized to impart mobility to deposited adatoms.", "According to the second approach, the ion beam is used to deposit one of the components from ion-dissociation of gas molecules (e.g. Si from SiH 4 or Ge from GeH 4 ion beams), while the other components are provided by thermal co-evaporation.", "The processes of the present invention give rise to good quality epitaxial films at low temperatures (e.g. in the range of 250°-350° C.).", "The most important advantage of the methods according to the present invention over the prior art are that the films are processed entirely at low temperatures and hence can be used for post-IC modifications (e.g. to add additional critical devices to an integrated circuit (IC) chip).", "The processes of the present invention can be integrated into state of the art IC fabrication sequences to realize various Si devices and SiGe hetero-junction devices.", "The processes of the present invention avoid the requirement of expensive fabrication equipment.", "A broad description of applicant's first process is provided in applicant's publication entitled "A Low Temperature Ion-Beam Assisted Deposition Method for Realizing SiGe/Si Heterostructures", Solid State Electronics, Volume 37, No. 8, pages 1467-1469, August 1994.", "BRIEF DESCRIPTION OF THE DRAWINGS A detailed description of the invention and its preferred embodiment is provided below with reference to the following drawings, in which: FIG. 1 is a schematic diagram of a vacuum deposition chamber for implementing a first process in accordance with the present invention;", "FIG. 2 is a SIMS profile of a prepared SiGe film on a Si substrate using the process discussed in connection with FIG. 1. FIG. 3 is a Rutherford back scattering spectra for the SiGe film on Si substrate discussed in connection with FIG. 2. FIG. 4(a) is a high resolution image of the SiGe-Si interfacial region displaying the micro-crystalline nature of the SiGe growth layer discussed above in connection with FIGS. 1-3.", "FIG. 4(b) shows the <001>", "zone axis selected area selectron diffraction pattern.", "FIG. 5(a) is a schematic diagram showing the steps in fabrication of an SiGe-Si iso-type diode using the first process in accordance with the present invention.", "FIG. 5(b) depicts the electrical equivalent circuit for the diode of FIG. 5(a), wherein R s results primarily from both ohmic resistance and contact resistance.", "FIG. 6 shows the current-voltage characteristics of the SiGe-Si iso-type diode of FIGS. 5(a) and 5(b) at different ambient temperatures.", "The inset shows the characteristics at a temperature of 150° K. with an "ideality"", "factor of 1.08.", "FIG. 7 shows an Arrhenius plot of the SiGe Si iso-type diode of FIGS. 5(a) and (b).", "The dotted straight line superimposed on the plot indicates an energy barrier height of 0.38 eV for the majority carriers (i.e. electrons).", "FIG. 8 shows a severe degradation of current-voltage characteristics of the iso-type diodes of FIGS. 5(a) and (b) after rapid thermal annealing at 800° C. for 30 seconds.", "FIG. 9 is a schematic diagram of the deposition chamber utilized in accordance with the second process of the present invention.", "FIG. 10(a) is a scanning electron micrograph for a sample prepared at 700° C. substrate temperature.", "FIG. 10b) is a scanning electron micrograph of the sample in FIG. 10(a) tilted at 65°.", "FIG. 10(c) shows a sample prepared at 500° C. FIG. 10(d) shows the sample of FIG. 10(c) tilted at 65° C. FIG. 11 is a cross sectional transmission electron microscopy (TEM), in which FIG. 11(a) shows a bright field [110] zone axis image of one of a plurality of pyramids grown at 700° C. The insert shows the electron diffraction pattern for the films and the substrate.", "FIG. 11(b) shows a high resolution cross-sectional TEM image for the sample in FIG. 11(a).", "FIG. 12(a) is a bright field image of a sample grown at 300° C. FIG. 12(b) is a high resolution TEM image for the sample in FIG. 12(a) showing epitaxial growth.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Turning to FIG. 1, an experimental set-up is shown for implementing the first process in accordance with the present invention.", "A 45 cm diameter glass cylinder vacuum chamber 1 is evacuated using a mechanical pump backing a diffusion pump (not shown).", "A liquid nitrogen cold trap (not shown) is used to reduce the level of water vapor during the film deposition.", "A base pressure of 1×10 -7 Torr (1.3×10 -5 Pa) is maintained.", "Silicon 2 and germanium 4 are evaporated using an electron gun 3 and an indirectly heated AlO 2 crucible source, respectively.", "A commercial Kaufman type IonTek ion gun 3 is used to bombard the surface of a substrate 5 during film deposition.", "Ultra high pure (UHP grade) argon is used as the source gas for the ion beam.", "The ion beam is directed towards the substrate 5 at an angle of 20° with respect to the normal to the sample surface.", "According to actual experiment, <100>, 1 Ωcm n-type silicon wafers were used as the substrate 5.", "The back of the substrate was doped with phosporous to enhance its back-side ohmic contact.", "The substrate 5 was cleaned using standard RCA solution and given an HF dip just before loading into the deposition chamber 1.", "The ion beam energy and current were set to 75 eV and 15 mA, respectively.", "The substrate temperature during film growth was maintained at 260° C. and was monitored using a thermocouple (not shown) located at the back side of the substrate 5.", "The deposition rate was monitored using a crystal microbalance positioned close to the substrate 5, and an average growth rate of 5 nm per minute was measured, resulting in a n-type doping of 2×10 19 cm -3 .", "Phosphorus co-evaporation was carried out in-situ from source 7 to dope the deposited SiGe film.", "Since the deposition was carried out at a low substrate temperature, the sticking coefficient of the phosphorus was close to unity.", "FIG. 2 shows the SIMS profile for the SiGe/Si sample product in accordance with the above-described process.", "In this Figure, Ge is plotted on a linear scale which shows a sharp step in its profile at the interface.", "FIG. 2 shows the creation of a SiGe film with a varying Ge concentration.", "Based on the SIMS results, a 40% Ge concentration is observed close to the Si-Ge interface and it sharply drops to an average of 15% in the rest of the film.", "The sharp increase in the Ge concentration is as a result of inadequate control at the beginning of the evaporation.", "The SIMS results also show that there is a high level of oxygen incorporated into the SiGe film with concentrations in the order of 1×10 21 cm -2 .", "This high oxygen content is believed to be due mainly to the low vacuum condition and high partial pressure of water vapor during film deposition.", "In order to investigate the nature of the films, Rutherford back scattering (RBS) and Cross-sectional TEM were employed.", "The sample was annealed at an ambient temperature of 800° C. for 30 seconds using a rapid thermal processing system (RTP).", "FIG. 3 shows the RBS spectra for the annealed sample.", "The random spectrum in this figure corroborates the presence of a SiGe film on the Si substrate with an average Ge concentration of 15%.", "The Ge fraction inferred from RBS is seen to substantially agree with the SIMS profile of FIG. 2. In addition to germanium, RBS also shows evidence for the incorporation of argon and its concentration is more than 5%.", "the ionization efficiency limit of the ion gun 3 used in this experiment is believed to be responsible for this high concentration of Ar in the SiGe film.", "The ion beam generated using this type of ion-gun, consists of both ionized and non-ionized Ar atoms.", "The non-ionized portion of the Ar flow is not characterized by substantial kinetic energy (except for kinetic energy imparted by thermal energy) and when the Ar flow collides with the substrate 5, a portion of the non-ionized Ar atoms is buried in the growing film without any means to escape.", "It is known that Ar incorporation should be kept below 0.2% in order to facilitate crystal regrowth, since the presence of high percentages of Ar can affect the crystallinity of the SiGe layer and impact device electrical characteristics.", "Another peak in the RBS is observed in the random spectrum of FIG. 3 which is believed to be due to tungsten (W).", "The incorporation of this element is believed to originate from the sublimation of the hot cathode filament used inside the ion gun 3.", "The concentration of this element in the film is about 0.1%.", "the channelled spectrum in FIG. 3 shows a yield of 15-20% less than the random spectrum indicating a partial alignment in the film crystal structure.", "This partial alignment in the film can be due to the micro-crystal structure of the SiGe layer.", "The structure of the SiGe-Si interface was studied using transmission electron microscopy (TEM).", "TEM samples in (110) cross-section were prepared by a cleavage technique, as set forth in J. McCaffery, "Small-angle Cleavage of Semiconductors for Transmission Electron Microscopy", Ultramicroscopy, vol.", "38, pp. 149-157, 1991.", "Plan view samples were prepared using standard ion milling techniques.", "All microscopy was performed using a Philips CM20 TEM operated at 200 kV.", "FIG. 4(a) shows a high resolution image of the annealed SiGe-Si interfracial region with the substrate 5 in a [110] zone axis orientation.", "The SiGe film is micro-crystalline and contrast due to the <111>", "fringes of individual crystals is clearly observable.", "Applying dark field diffraction contrast techniques, the sizes of the crystallites composing the micro-crystalline layer were found to range from 5 to 9 nm.", "FIG. 4(b) is a <001>", "selected area diffraction pattern obtained from a plan view of the specimen.", "The individual spots are due to the Si substrate 5.", "Sharp rings around each of the spots are produced by the SiGe film and give further evidence to the micro-crystalline nature of the SiGe layer.", "SiGe/Si iso-type diodes were fabricated using ion-beam assisted deposition according to the process described above, at a temperature of approximately 250° C. Starting with an n on n+ silicon wafer 8 (FIG.", "5(a) (i)), a phosphorus doped SiGe film 10 was deposited (FIG.", "5(a)(ii) followed by a deposition of aluminum contacts 12 on the film using a shadow masking technique.", "The aluminum deposition 14 on the back side completed the iso-type diode fabrication (FIG.", "5(a)(iii).", "The completed diodes were annealed in Forming gas at 250° C. for 20 mins.", "The diode area in this experiment was 1.5×10 -2 cm -2 .", "Some randomly selected diodes were chosen to be installed in a low temperature micorprobe to study the device characteristics at different ambient temperatures.", "The current-voltage characteristics of the diodes were measured using a HP-4145B parameter analyzer.", "FIG. 5(b) shows a simple electrical equivalent circuit model for the iso-type diodes fabricated as described above.", "Since the saturation current in such diodes is fairly high, the influence of the series resistance R s is significant.", "Considering the current-voltage relation for a typical diode, the effect of series resistance R s on the diode characteristics can be determined.", "Part of the applied voltage on the diode (D), drops across this resistor (R s ), reducing the voltage appearing across the intrinsic junction to Vd as in: ##EQU1## where I and V d are the diode current and voltage, respectively.", "I o is the diode reverse saturation current, V tot is the total voltage applied across the diode and R s is the resistance in series with the junction.", "The series resistance is in part due to the bulk resistance of the substrate 8 and in part due to the contact resistance of the metallization 12 and 14.", "By lowering the temperature, the deleterious effects of the series resistance can be made less dominant.", "FIG. 6 shows the current-voltage characteristics of the iso-type diode of FIG. 5 measured at different ambient temperatures.", "At temperatures below 170K, an ideal exponential regime becomes apparent.", "The inset in FIG. 6 shows the I-V characteristic for an iso-type diode at a temperature of 150K with an ideality factor of 1.08 persisting over three decades of current and beyond this it is limited by the series resistance.", "The behaviour of the diode remains ideal for temperatures as low as the liquid nitrogen temperature where it is limited by the resolution capabilities of the parameter analyzer and level of noise.", "Both reverse saturation current as well as the forward current strongly depend on the ambient temperature.", "FIG. 7 shows the Arrhenius plot for the diode at an applied forward voltage of 0.1 V. The exponential decrease of the current with temperature suggests that there is a barrier at the film-substrate interface which blocks the flow of majority carriers (electrons).", "This barrier can be modeled as: ##EQU2## where I c shows the reverse saturation current and E b represents the energy barrier for majority carriers.", "Considering Eqn.", "(1) and ignoring the effect of the series resistance, the forward current at a voltage of 0.1 V can be obtained from: ##EQU3## The straight line superimposed on the experimental results of FIG. 7 shows the phenomenological current-temperature characteristics predicted by Eqn.", "(3) and based on this a barrier height of 0.38 eV is obtained.", "For temperatures below 130K, the measured current is more than that predicted by Eqn.", "(3), but at this point the resolution of the parameter analyzer becomes crucial since it cannot measure currents below 10 -11 A. the formation of such a barrier can be due to the presence of interface states at the SiGe-Si interface, similar to Schottky barrier formation.", "These states are mostly generated by the dangling bonds of the substrate Si atoms.", "The presence of such a barrier is not seen for the epitaxially grown SiGe films on Si substrate.", "FIG. 8 shows the current-voltage characteristics for this sample after rapid thermal annealing at 800° C. for 30 seconds.", "Although the thermal treatment time was short, it is seen to significantly degrade the I-V results.", "This extensive degradation of the diode behaviour can be accounted for by the activation of defects at the interface.", "As indicated by the I-V characteristics, the behaviour remains extremely non-ideal at all ambient temperatures.", "To summarize, the static electrical characteristics show good rectifying behaviour of the fabricated n+SiGe/n-Si iso-type hetero-junction diodes with an ideality factor close to unity.", "At room temperature the reverse saturation current is large and the I-V characteristic is mainly limited by the series resistance.", "At lower temperatures, it has been shown that the saturation current drops expoentially and the shadowing effect of the series resistance is minimized and the I-V characteristic of the diode exhibits a clear exponential regime.", "For a wide range of ambient temperatures (90° K.-180° K.), the diode exhibits exponential I-V characteristic with an ideality factor close to unity over three decades of current.", "Based on the temperature dependent electrical characteristics of this device and using a simple energy barrier model, it was found that an energy barrier of 0.38 eV appears to fit the observed characteristic as: ##EQU4## where E b denotes the energy barrier at the SiGe-Si junction.", "Although the SiGe-Si interface states can be responsible for the formation of such an energy barrier, they do not seem to degrade the I-V characteristics of the diode by causing generation or recombination currents that would affect the ideality factor.", "High temperature annealing of the film drastically degrades the electrical characteristics as seen by the I-V characteristics at all temperatures investigated.", "This non-ideal I-V behaviour is believed to be mainly due to the formation of recombination (or generation) centers at the interface.", "According to the second process of the present invention, an inexpensive ion beam vapor deposition technique is provided to grow thin semiconductor films derived from ion-dissociation of the semiconductor from gas molecules.", "According to experiment, silicon films were grown at different substrate temperatures and their atomic structures studied using electron microscopy.", "The equipment used for this study is illustrated in FIG. 9. A cylindrical vacuum chamber 11 is pumped by a diffusion pump (not shown), equipped with a liquid nitrogen cold trap (not shown) and backed by a rotary mechanical pump (not shown).", "A base pressure of 1×10 -7 Torr (1.3×10 -5 Pa) is typically attained.", "A commercially available IonTek Kaufman type ion source 13 was used to ionize the gas and to accelerate the ion beam towards the substrate.", "The ion gun 13 bombarded the surface of a substrate 15 at an angle of 20° with respect to the normal of its surface.", "The ion beam energy and current can be adjusted between 30-1000 eV and 0-30 mA, respectively.", "Ultra high purity argon and silane (SiH 4 ) gasses with 99.999% purity were used as sources for the ion beam.", "Alternatively, a Ge film can be grown by using GeH 4 as the source of gas molecules.", "For the gun 13 to operate, a chamber pressure of 0.5-2×10 -4 Torr (0.65-2.6×10 -2 Pa) is required.", "For testing purposes, 1Ω-cm n-type <100>", "Si substrates 15 were used.", "Each Si substrate was cleaned for 15 mins.", "in a standard RCA solution.", "Before loading the Si wafer into the chamber, it was etched in HF followed by a rinse with D.I. water and a N2 blow-dry.", "After loading the sample and pump-down cycle, the sample was heated to 300° C. In-situ cleaning of the substrate surface was done by argon ion bombardment prior to the start of deposition.", "This is a necessary step which significantly influences the quality of the grown film.", "A 200 eV argon ion beam was used to sputter-clean the substrate at a low substrate temperature (≈50° C.).", "This low energy ion cleaning was found to be sufficient to remove the native oxide.", "After 5 mins.", "of Ar ion bombardment, the Ar line was closed and the ion gun 13 was shut down.", "The substrate temperature was set by radiation heating from a tungsten filament (not shown) mounted in a stainless steel box.", "The substrate temperature was raised to a temperature in the range of 700° C. to 800° C. in about one minute, and held at that temperature from 30 seconds to 1 min.", ", to anneal surface damage caused by the energetic ion bombardment.", "The high temperature annealing step before deposition can be eliminated if a proper Ar + -ion beam energy is used.", "This energy must be low to avoid damaging the substrate, yet it must be strong enough to remove a few monolayers of the native oxide or adsorbed molecules on the substrate surface.", "It has been found that an ion beam energy of 40 eV at a substrate temperature of 340° C. is sufficient to remove the few monolayers of oxide and absorbed molecules on the substrate without introducing significant damage.", "The substrate temperature was then lowered to its desired value (300°-700° C.) to start the deposition.", "However, planar growth of Si and SiGe films can be achieved at temperatures as low as 250° C. SiH 4 gas was introduced to the ion source 13 and the deposition took place at a chamber pressure of 8×10 -5 Torr (although deposition can be carried out a pressures as low as 5×10 -4 Torr.) During the film growth, an ion beam energy of 50 eV and a current of 13 mA were used.", "The ion beam intensity at the substrate surface was 30 μA cm -2 and it was measured by a Faraday cup.", "Following the deposition cycle, the substrate temperature was allowed to cool down.", "It was observed that at this pressure (8×10 -5 Torr), no deposition occurred on the parts of the substrate 15 which were not directly exposed to the ion gun.", "The as-grown samples produced by the above described process were used for an electron microscopy study.", "FIG. 10a shows a scanning electron microscopy (SEM) image of a sample grown at 700° C. Rectangle-based pyramids as large as 1 μm in length and 0.3 μm in height, oriented with the (100) directions parallel to the substrate, are observed.", "The micrograph also indicates that many of the pyramids have elongated rectangular bases which are believed to be due to preferential growth influenced by the direction of the incident ion beam.", "FIG. 10(b) displays the tilted image for the same sample.", "As shown in this figure, the surface is covered by pyramids with (111) and (113) faces exposed.", "FIG. 10(c) shows a micrograph of the sample grown at 500° C. evidencing 3-D growth.", "It appears that the substrate surface is more completely covered at this lower temperature.", "Although it is difficult to determine the exact thickness of these three-dimensional films, it is evident that at lower temperatures the pyramid heights are less and their distribution is more uniform.", "Since the kinetic energy of the ion beam is required to dissociate the SiH4 molecules, the total number of Si atoms deposited on the substrate is independent of the substrate temperature.", "At an ion beam energy of 50 eV, the thermal energy of molecules (kT) is about three orders of magnitude smaller than the ion kinetic energy.", "FIG. 19(d) shows a higher magnification SEM image for the same sample.", "The size of the pyramids is also smaller.", "The difference in the coverage of the substrate surface is believed to be due to differences in the Si adatom mobilities.", "Part of the adatom surface mobility derives from thermal energy gained from the substrate and part from the kinetic energy of the ion beam.", "At higher substrate temperatures the surface mobility of adatoms is high and they can travel further before they bond with the underlayer.", "This can result in the formation of islands which are elongated in a preferred direction under the influence of the ion beam.", "By lowering the temperature of the growth, the total surface mobility is reduced and the probability for planar growth is increased.", "To study the crystalline quality of the prepared samples, high resolution transmission electron microscopy (HRTEM) was used.", "In this study, a small angle cleavage technique was used for the TEM specimen preparations.", "FIG. 11(a) shows a bright field [110] zone axis image of the sample grown at 700° C. The exposed atomic planes, (111) and (113), are observed in this figure.", "FIG. 11(b) displays a high resolution cross-sectional TEM image for the film-substrate interface of this sample.", "Few interfacial defects are observed in this figure indicating a reasonably good quality film.", "Electron diffraction analysis also indicates that the islands are epitaxially grown.", "The sample prepared using a 700° C. substrate temperature shows a planar growth.", "FIG. 12(a) displays the bright field [110] zone axis image for this sample indicating planar growth.", "The bright spots at the film-substrate interface are believed to be due to disordered Si at the interface resulting from the energetic Ar ion bombardment, when there has been insufficient annealing.", "FIG. 12(b) depicts a high resolution micrograph of the same sample clearly showing the epitaxial growth.", "The high resolution image also shows the presence of a large concentration of twins and microtwins, originating from the interface.", "Inadequate in-situ cleaning is believed to be responsible for the observed planar defects.", "It is contemplated that the damage created due to the 200 eV Ar ion bombardment may be too significant to be adequately repaired by a short annealing time.", "In comparison with the image in FIG. 11(b), it is seen that the higher temperature growth (700° C.) repairs the damage produced by such energic Ar bombardment.", "Al-Bayati et al.", "have recently studied the effect of substrate temperature on film quality using a mass selected ion beam deposition technique (see ref. K. J. Orrman-Rossiter, A. H. Al-Bayati, D. G. Armour, S. E. Donnely and J. A. van den Berg, Nucl.", "Instrum.", "Methods B 59/60, 197 (1991);", "and A. H. Bayati, K. J. Boyd, D. Marton, S. S. Todorov, J. W. Rabalais, Z. H. Zhang and W. K. Chu, Appl.", "Phys.", ", 57 2757 (1985)).", "In their study, substrate temperatures above 350° C. were found to degrade the quality of the Si films, which is a result which seems to corroborate the experimental observations conducted with respect to the present invention.", "Ge incorporation into the Si film can be accomplished by thermal evaporation of elemental Ge from a B-N crucible in a manner similar to that discussed above in connection with the first described process (FIGS.", "1-8).", "A portion of the energy of the arriving Si adatoms is imparted to Ge adatoms thereby enhancing their surface mobility and hence the probability of epitaxial growth at reduced temperatures.", "In conclusion, a simple and inexpensive technique is provided according to the present invention for growing silicon and silicon-germanium thin films.", "Depending on the substrate temperature, the films exhibit one of either island or planar growth.", "With the substrate at a higher temperature, 3-D growth with pronounced pyramids was observed.", "By lowering the substrate temperature, the probability of achieving planar growth is enhanced.", "At a substrate temperature of 300° C., planar growth was realized.", "In-situ cleaning of the sample is an important step of the second described process according to the present invention, and this is achieved by Ar ion bombardment at low temperatures followed by an in-situ annealing.", "Results from high resolution transmission electron microscopy, electron diffraction, Raman spectroscopy and scanning electron microscopy confirm the crystalline quality of the films grown by this technique.", "In addition, electrical characteristics of gallium-doped P-N junction diodes, realized using this approach, show good rectifying behaviour.", "Specifically, gallium-doped p-n junction diodes have been fabricated according to the process of the present invention by opening windows on an already completed integrated circuit chip having aluminum metallization.", "Other embodiments and variations are possible within the sphere and scope of the present invention as defined by the claims appended hereto." ]